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Sample records for organic solar cell

  1. Organic Solar Cells: Absolute Measurement of Domain Composition...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Organic Solar Cells: Absolute Measurement of Domain Composition and Nanoscale Size Distribution Explains Performance in Solar Cells Organic Solar Cells: Absolute Measurement of...

  2. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive...

  3. Understanding Collection-Related Losses in Organic Solar Cells...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Understanding Collection-Related Losses in Organic Solar Cells Home > Research > ANSER Research Highlights > Understanding Collection-Related Losses in Organic Solar Cells...

  4. Organic Solar Cells: Absolute Measurement of Domain Composition and

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nanoscale Size Distribution Explains Performance in Solar Cells Organic Solar Cells: Absolute Measurement of Domain Composition and Nanoscale Size Distribution Explains Performance in Solar Cells Organic Solar Cells: Absolute Measurement of Domain Composition and Nanoscale Size Distribution Explains Performance in Solar Cells Print Tuesday, 22 January 2013 00:00 This front cover represents the morphology and resulting device dynamics in organic solar cell blend films of PTB7 and PC71BM, as

  5. Understanding Collection-Related Losses in Organic Solar Cells | ANSER

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Center | Argonne-Northwestern National Laboratory Understanding Collection-Related Losses in Organic Solar Cells Home > Research > ANSER Research Highlights > Understanding Collection-Related Losses in Organic Solar Cells

  6. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells New Morphological Paradigm Uncovered in Organic Solar Cells Print Wednesday, 27 April 2011 00:00 Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models

  7. Hybrid Organic-Inorganic Halide Perovskite Solar Cells | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Hybrid Organic-Inorganic Halide Perovskite Solar Cells Hybrid Organic-Inorganic Halide Perovskite Solar Cells The SunShot Initiative supports research and development projects aimed at increasing the efficiency and lifetime as well as evaluating new materials for hybrid organic-inorganic perovskite solar cells. This field has been dominated by absorber materials based on methylammonium lead halide perovskites. Perovskite solar cells have shown remarkable progress in recent years with

  8. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  9. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  10. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  11. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  12. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  13. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  14. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  15. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Morphological Paradigm Uncovered in Organic Solar Cells Print Organic solar cells are made of light, flexible, renewable materials; they require simple and inexpensive processing steps and could produce an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models describing critical device functions such as charge separation and transport often depend on

  16. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    layer. This improved understanding will guide the future development and optimization of organic solar cells by reducing laborious trial-and-error development and forcing other...

  17. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum potential. Models...

  18. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum...

  19. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    an economically competitive and environmentally friendly energy source. Understanding the fundamentals of organic solar cell function is therefore vital to uncovering their maximum...

  20. Air stable organic-inorganic nanoparticles hybrid solar cells

    DOE Patents [OSTI]

    Qian, Lei; Yang, Jihua; Xue, Jiangeng; Holloway, Paul H.

    2015-09-29

    A solar cell includes a low work function cathode, an active layer of an organic-inorganic nanoparticle composite, a ZnO nanoparticle layer situated between and physically contacting the cathode and active layers; and a transparent high work function anode that is a bilayer electrode. The inclusion of the ZnO nanoparticle layer results in a solar cell displaying a conversion efficiency increase and reduces the device degradation rate. Embodiments of the invention are directed to novel ZnO nanoparticles that are advantageous for use as the ZnO nanoparticle layers of the novel solar cells and a method to prepare the ZnO nanoparticles.

  1. Recyclable organic solar cells on substrates comprising cellulose nanocrystals (CNC)

    DOE Patents [OSTI]

    Kippelen, Bernard; Fuentes-Hernandez, Canek; Zhou, Yinhua; Moon, Robert; Youngblood, Jeffrey P

    2015-12-01

    Recyclable organic solar cells are disclosed herein. Systems and methods are further disclosed for producing, improving performance, and for recycling the solar cells. In certain example embodiments, the recyclable organic solar cells disclosed herein include: a first electrode; a second electrode; a photoactive layer disposed between the first electrode and the second electrode; an interlayer comprising a Lewis basic oligomer or polymer disposed between the photoactive layer and at least a portion of the first electrode or the second electrode; and a substrate disposed adjacent to the first electrode or the second electrode. The interlayer reduces the work function associated with the first or second electrode. In certain example embodiments, the substrate comprises cellulose nanocrystals that can be recycled. In certain example embodiments, one or more of the first electrode, the photoactive layer, and the second electrode may be applied by a film transfer lamination method.

  2. Interface engineering for efficient fullerene-free organic solar cells

    SciTech Connect (OSTI)

    Shivanna, Ravichandran; Narayan, K. S. E-mail: narayan@jncasr.ac.in; Rajaram, Sridhar E-mail: narayan@jncasr.ac.in

    2015-03-23

    We demonstrate the role of zinc oxide (ZnO) morphology and addition of an acceptor interlayer to achieve high efficiency fullerene-free bulk heterojunction inverted organic solar cells. Nanopatterning of the ZnO buffer layer enhances the effective light absorption in the active layer, and the insertion of a twisted perylene acceptor layer planarizes and decreases the electron extraction barrier. Along with an increase in current homogeneity, the reduced work function difference and selective transport of electrons prevent the accumulation of charges and decrease the electron-hole recombination at the interface. These factors enable an overall increase of efficiency to 4.6%, which is significant for a fullerene-free solution-processed organic solar cell.

  3. Organics Energize Solar Cell Research | Argonne Leadership Computing...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    energy we have only recently begun to harvest and convert into electricity. Today, most solar panel technologies rely on crystalline silicon photovoltaic cells. Despite their...

  4. Scientists at ALS Find New Path to More Efficient Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientists at ALS Find New Path to More Efficient Organic Solar Cells Scientists at ALS Find New Path to More Efficient Organic Solar Cells Print Monday, 07 January 2013 00:00 Harald Ade, a physicist at North Carolina State University, led a study at the Advanced Light Source that revealed a second pathway to improved performances of polymer/organic solar cells. Whereas the first pathway demands crystals of ultrapure domains, the new pathway shows that impure domains if sufficiently small can

  5. Fabrication and characterization of organic solar cells using metal complex of phthalocyanines

    SciTech Connect (OSTI)

    Kida, Tomoyasu Suzuki, Atsushi Akiyama, Tsuyoshi Oku, Takeo

    2015-02-27

    Fabrication and characterization of organic solar cells using shuttle-cock-type phthalocyanines were carried out. Photovoltaic properties of the solar cells with inverted structures were investigated by current density-voltage characteristics. Effects of phase transition between H and J aggregates on the photovoltaic and optical properties were investigated. The photovoltaic mechanisms, energy levels and band gap of active layers were discussed.

  6. More stable hybrid organic solar cells deposited on amorphous Si electron transfer layer

    SciTech Connect (OSTI)

    Samiee, Mehran; Modtland, Brian; Dalal, Vikram L.; Aidarkhanov, Damir

    2014-05-26

    We report on defect densities, performance, and stability of organic/inorganic hybrid solar cells produced using n-doped inorganic amorphous silicon-carbide layers as the electron transport layer (ETL). The organic material was poly-3-hexyl-thiophene (P3HT) and heterojunction was formed using phenyl-C{sub 71}-Butyric-Acid-Methyl Ester (PCBM). For comparison, inverted solar cells fabricated using Cs{sub 2}CO{sub 3} as ETL were fabricated. Defect densities and subgap quantum efficiency curves were found to be nearly identical for both types of cells. The cells were subjected to 2xsun illumination and it was found that the cells produced using doped a-Si as ETL were much more stable than the cells produced using Cs{sub 2}CO{sub 3}.

  7. Effect of simultaneous electrical and thermal treatment on the performance of bulk heterojunction organic solar cell blended with organic salt

    SciTech Connect (OSTI)

    Sabri, Nasehah Syamin; Yap, Chi Chin; Yahaya, Muhammad; Salleh, Muhamad Mat

    2013-11-27

    This work presents the influence of simultaneous electrical and thermal treatment on the performance of organic solar cell blended with organic salt. The organic solar cells were composed of indium tin oxide as anode, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene]: (6,6)-phenyl-C61 butyric acid methyl ester: tetrabutylammonium hexafluorophosphate blend as organic active layer and aluminium as cathode. The devices underwent a simultaneous fixed-voltage electrical and thermal treatment at different temperatures of 25, 50 and 75 °C. It was found that photovoltaic performance improved with the thermal treatment temperature. Accumulation of more organic salt ions in the active layer leads to broadening of p-n doped regions and hence higher built-in electric field across thin intrinsic layer. The simultaneous electrical and thermal treatment has been shown to be able to reduce the electrical treatment voltage.

  8. Iran Thomas Auditorium, 8600 Electronic and Optical Processes in Organic Solar Cells:

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    12, 2010 11:00 am Iran Thomas Auditorium, 8600 Electronic and Optical Processes in Organic Solar Cells: Theoretical Description of Organic-Organic Interfaces Jean-Luc Bredas School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics Georgia Institute of Technology CNMS D D I I S S C C O O V V E E R R Y Y SEMINAR SERIES Abstract: This presentation work seeks to provide a detailed theoretical description of the electronic and optical processes taking place in organic

  9. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    a more likely morphology based on the current study. The absorption of a photon in organic photovoltaics (OPVs) results in a bound exciton (electronhole pair) that must be...

  10. molecular nature of photovoltage losses in organic solar cells

    SciTech Connect (OSTI)

    Schlenker, Cody W.; Thompson, Mark E.

    2011-01-01

    Since the inception of heterojunction organic photovoltaic research the organic/organic interface has been thought to play a crucial role in determining the magnitude of the open-circuit voltage. Yet, the task of defining the molecular properties dictating the photovoltage delivered by these devices, that employ mixed or neat layers of different organic molecules to convert incident photons to electricity, is still an active area of research. This will likely be a key step in designing the new materials required for improving future device efficiencies. With the intent to underscore the importance of considering both thermodynamic and kinetic factors, this article highlights recent progress in elucidating molecular characteristics dictating photovoltage losses in heterojunction organic photovoltaics.

  11. Low resistance thin film organic solar cell electrodes

    DOE Patents [OSTI]

    Forrest, Stephen (Princeton, NJ); Xue, Jiangeng (Piscataway, NJ)

    2008-01-01

    A method which lower the series resistance of photosensitive devices includes providing a transparent film of a first electrically conductive material arranged on a transparent substrate; depositing and patterning a mask over the first electrically conductive material, such that openings in the mask have sloping sides which narrow approaching the substrate; depositing a second electrically conductive material directly onto the first electrically conductive material exposed in the openings of the mask, at least partially filling the openings; stripping the mask, leaving behind reentrant structures of the second electrically conductive material which were formed by the deposits in the openings of the mask; after stripping the mask, depositing a first organic material onto the first electrically conductive material in between the reentrant structures; and directionally depositing a third electrically conductive material over the first organic material deposited in between the reentrant structures, edges of the reentrant structures aligning deposition so that the third electrically conductive material does not directly contact the first electrically conductive material, and does not directly contact the second electrically conductive material.

  12. Nanophase Engineering of Organic Semiconductor-based Solar Cells

    SciTech Connect (OSTI)

    Yang, Bin; Shao, Ming; Keum, Jong Kahk; Geohegan, David B; Xiao, Kai

    2015-01-01

    Organic photovoltaics are promising low-cost, easily-processable energy sources of the future, and are the subject of current academic and industrial interest. In order to achieve the envisioned device efficiencies to surpass commercialization target values, several challenges must be met: (1) to design and synthesize conjugated molecules with low optical bandgaps and optimized electronic energy levels, (2) optimization the morphology of donor/acceptor interpenetrating networks by controlling nanoscale phase separation and self-assembly, and (3) precise tuning of the active layer/electrode interfaces and donor/acceptor interfaces for optimized charge transfer. Here, we focus on recent advances in: (i) synthetic strategies for low-bandgap conjugated polymers and novel fullerene acceptors, (ii) processing to tune film morphologies by solvent annealing, thermal annealing, and the use of solvent additives and compatibilizers, and (iii) engineering of active layer/electrode interfaces and donor/acceptor interfaces with self-assembled monolayer dipoles.

  13. Highly efficient inverted organic solar cells using amino acid modified indium tin oxide as cathode

    SciTech Connect (OSTI)

    Li, Aiyuan; Nie, Riming; Deng, Xianyu; Wei, Huaixin; Li, Yanqing; Tang, Jianxin; Zheng, Shizhao; Wong, King-Young

    2014-03-24

    In this paper, we report that highly efficient inverted organic solar cells were achieved by modifying the surface of indium tin oxide (ITO) using an amino acid, Serine (Ser). With the modification of the ITO surface, device efficiency was significantly enhanced from 0.63% to 4.17%, accompanied with an open circuit voltage (Voc) that was enhanced from 0.30?V to 0.55?V. Ultraviolet and X-ray photoelectron spectroscopy studies indicate that the work function reduction induced by the amino acid modification resulting in the decreased barrier height at the ITO/organic interface played a crucial role in the enhanced performances.

  14. Highly efficient organic multi-junction solar cells with a thiophene based donor material

    SciTech Connect (OSTI)

    Meerheim, Rico Körner, Christian; Leo, Karl

    2014-08-11

    The efficiency of organic solar cells can be increased by serial stacked subcells even upon using the same absorber material. For the multi-junction devices presented here, we use the small molecule donor material DCV5T-Me. The subcell currents were matched by optical transfer matrix simulation, allowing an efficiency increase from 8.3% for a single junction up to 9.7% for a triple junction cell. The external quantum efficiency of the subcells, measured under appropriate light bias illumination, is spectrally shifted due to the microcavity of the complete stack, resulting in a broadband response and an increased cell current. The increase of the power conversion efficiency upon device stacking is even stronger for large area cells due to higher influence of the resistance of the indium tin oxide anode, emphasizing the advantage of multi-junction devices for large-area applications.

  15. Development of nanostructured and surface modified semiconductors for hybrid organic-inorganic solar cells.

    SciTech Connect (OSTI)

    Hsu, Julia, W. P.

    2008-09-01

    Solar energy conversion is increasingly being recognized as one of the principal ways to meet future energy needs without causing detrimental environmental impact. Hybrid organic-inorganic solar cells (SCs) are attracting particular interest due to the potential for low cost manufacturing and for use in new applications, such as consumer electronics, architectural integration and light-weight sensors. Key materials advantages of these next generation SCs over conventional semiconductor SCs are in design opportunities--since the different functions of the SCs are carried out by different materials, there are greater materials choices for producing optimized structures. In this project, we explore the hybrid organic-inorganic solar cell system that consists of oxide, primarily ZnO, nanostructures as the electron transporter and poly-(3-hexylthiophene) (P3HT) as the light-absorber and hole transporter. It builds on our capabilities in the solution synthesis of nanostructured semiconducting oxide arrays to this photovoltaic (PV) technology. The three challenges in this hybrid material system for solar applications are (1) achieving inorganic nanostructures with critical spacing that matches the exciton diffusion in the polymer, {approx} 10 nm, (2) infiltrating the polymer completely into the dense nanostructure arrays, and (3) optimizing the interfacial properties to facilitate efficient charge transfer. We have gained an understanding and control over growing oriented ZnO nanorods with sub-50 nm diameters and the required rod-to-rod spacing on various substrates. We have developed novel approaches to infiltrate commercially available P3HT in the narrow spacing between ZnO nanorods. Also, we have begun to explore ways to modify the interfacial properties. In addition, we have established device fabrication and testing capabilities at Sandia for prototype devices. Moreover, the control synthesis of ZnO nanorod arrays lead to the development of an efficient anti-reflection coating for multicrystalline Si solar cells. An important component of this project is the collaboration with Dr. Dave Ginley's group at NREL. The NREL efforts, which are funded by NREL's LDRD program, focus on measuring device performance, external quantum efficiency, photoconductance through highly specialized non-contact time-resolved microwave conductivity (TRMC) measurements, and vapor phase deposition of oxide materials. The close collaboration with NREL enables us to enter this competitive field in such short time. Joint publications and presentations have resulted from this fruitful collaboration. To this date, 5 referred journal papers have resulted from this project, with 2 more in preparation. Several invited talks and numerous contributed presentations in international conferences are also noted. Sandia has gained the reputation of being one of forefront research groups on nanostructured hybrid solar cells.

  16. Charge Recombination, Transport Dynamics, and Interfacial Effects in Organic Solar Cells

    SciTech Connect (OSTI)

    Heeger, Alan; Bazan, Guillermo; Nguyen, Thuc-Quyen; Wudl, Fred

    2015-02-27

    The need for renewable sources of energy is well known. Conversion of sunlight to electricity using solar cells is one of the most important opportunities for creating renewable energy sources. The research carried out under DE-FG02-08ER46535 focused on the science and technology of “Plastic” solar cells comprised of organic (i.e. carbon based) semiconductors. The Bulk Heterojunction concept involves a phase separated blend of two organic semiconductors each with dimensions in the nano-meter length scale --- one a material that functions as a donor for electrons and the other a material that functions as an acceptor for electrons. The nano-scale inter-penetrating network concept for “Plastic” solar cells was created at UC Santa Barbara. A simple measure of the impact of this concept can be obtained from a Google search which gives 244,000 “hits” for the Bulk Heterojunction solar cell. Research funded through this program focused on four major areas: 1. Interfacial effects in organic photovoltaics, 2. Charge transfer and photogeneration of mobile charge carriers in organic photovoltaics, 3. Transport and recombination of the photogenerated charge carriers in organic photovoltaics, 4. Synthesis of novel organic semiconducting polymers and semiconducting small molecules, including conjugated polyelectrolytes. Following the discovery of ultrafast charge transfer at UC Santa Barbara in 1992, the nano-organic (Bulk Heterojunction) concept was formulated. The need for a morphology comprising two interpenetrating bicontinuous networks was clear: one network to carry the photogenerated electrons (negative charge) to the cathode and one network to carry the photo-generated holes (positive charge) to the anode. This remarkable self-assembled network morphology has now been established using Transmission electron Microscopy (TEM) either in the Phase Contrast mode or via TEM-Tomography. The steps involved in delivering power from a solar cell to an external circuit are the following: • Photo-excitation of the donor (or the acceptor). • Charge transfer with holes in the donor domain and electrons in the acceptor domain. • Sweep-out to electrodes prior to recombination by the internal electric field. • Energy delivered to the external circuit. Each of these four steps was studied in detail using a wide variety of organic semiconductors with different molecular structures. This UC Santa Barbara group was the first to clarify the origin and the mechanism involved in the ultrafast charge transfer process. The ultrafast charge transfer (time scale approximately 100 times faster than the first step in the photo-synthesis of green plants) is the fundamental reason for the potential for high power conversion efficiency of sunlight to electricity from plastic solar cells. The UCSB group was the first to emphasize, clarify and demonstrate the need for sweep-out to electrodes prior to recombination by the internal electric field. The UCSB group was the first to synthesize small molecule organic semiconductors capable of high power conversion efficiencies. The results of this research were published in high impact peer-reviewed journals. Our published papers (40 in number) provide answers to fundamental questions that have been heavily discussed and debated in the field of Bulk Heterojunction Solar Cells; scientific questions that must be resolved before this technology can be ready for commercialization in large scale for production of renewable energy. Of the forty publications listed, nineteen were co-authored by two or more of the PIs, consistent with the multi-investigator approach described in the original proposal. The specific advantages of this “plastic” solar cell technology are the following: a. Manufacturing by low-cost printing technology using soluble organic semiconductors; this approach can be implemented in large scale by roll-to-roll printing on plastic substrates. b. Low energy cost in manufacturing; all steps carried out at room temperature (approx. a factor of ten less than the use of Silicon which requires high temperature processing). c. Low carbon footprint d. Lightweight, flexible and rugged Because of the resolution of many scientific issues, a significant fraction of which were addressed in the research results of DE-FG02-08ER46535, the power conversion efficiencies are improving at an ever increasing rate. During the funding period of DE-FG02-08ER46535, the power conversion efficiencies of plastic solar cells improved from just a few per cent to values greater than 11% with contributions from our group and from researchers all over the world.

  17. Single Molecule Spectroelectrochemistry of Interfacial Charge Transfer Dynamics In Hybrid Organic Solar Cell

    SciTech Connect (OSTI)

    Pan, Shanlin

    2014-11-16

    Our research under support of this DOE grant is focused on applied and fundamental aspects of model organic solar cell systems. Major accomplishments are: 1) we developed a spectroelectorchemistry technique of single molecule single nanoparticle method to study charge transfer between conjugated polymers and semiconductor at the single molecule level. The fluorescence of individual fluorescent polymers at semiconductor surfaces was shown to exhibit blinking behavior compared to molecules on glass substrates. Single molecule fluorescence excitation anisotropy measurements showed the conformation of the polymer molecules did not differ appreciably between glass and semiconductor substrates. The similarities in molecular conformation suggest that the observed differences in blinking activity are due to charge transfer between fluorescent polymer and semiconductor, which provides additional pathways between states of high and low fluorescence quantum efficiency. Similar spectroelectrochemistry work has been done for small organic dyes for understand their charge transfer dynamics on various substrates and electrochemical environments; 2) We developed a method of transferring semiconductor nanoparticles (NPs) and graphene oxide (GO) nanosheets into organic solvent for a potential electron acceptor in bulk heterojunction organic solar cells which employed polymer semiconductor as the electron donor. Electron transfer from the polymer semiconductor to semiconductor and GO in solutions and thin films was established through fluorescence spectroscopy and electroluminescence measurements. Solar cells containing these materials were constructed and evaluated using transient absorption spectroscopy and dynamic fluorescence techniques to understand the charge carrier generation and recombination events; 3) We invented a spectroelectorchemistry technique using light scattering and electroluminescence for rapid size determination and studying electrochemistry of single NPs in an electrochemical cell. For example, we are able to use this technique to track electroluminescence of single Au NPs, and the electrodeposition of individual Ag NPs in-situ. These metallic NPs are useful to enhance light harvesting in organic photovoltaic systems. The scattering at the surface of an indium tin oxide (ITO) working electrode was measured during a potential sweep. Utilizing Mie scattering theory and high resolution scanning electron microscopy (SEM), the scattering data were used to calculate current-potential curves depicting the electrodeposition of individual Ag NPs. The oxidation of individual presynthesized and electrodeposited Ag NPs was also investigated using fluorescence and DFS microscopies. Our work has produced 1 US provisional patent, 15 published manuscripts, 1 submitted and two additional in-writing manuscripts. 5 graduate students, 1 postdoctoral student, 1 visiting professor, and two undergraduate students have received research training in the area of electrochemistry and optical spectroscopy under support of this award.

  18. A water-processable organic electron-selective layer for solution-processed inverted organic solar cells

    SciTech Connect (OSTI)

    Chen, Dongcheng; Zhou, Hu; Cai, Ping; Sun, Shi; Ye, Hua; Su, Shi-Jian Cao, Yong

    2014-02-03

    A triazine- and pyridinium-containing water-soluble material of 1,1?,1?-(4,4?,4?-(1,3,5-triazine-2,4,6-triyl)tris(benzene-4,1-diyl)) tris(methylene)tripyridinium bromide (TzPyBr) was developed as an organic electron-selective layer in solution-processed inverted organic solar cells due to its strong anti-erosion capacity against non-polar organic solvents commonly used for the active layer. Ohmic-like contact with the adjacent active materials like fullerene derivatives is speculated to be formed, as confirmed by the work-function measurements with scanning Kelvin probe and ultraviolet photoelectron spectroscopy techniques. Besides, considering the deep highest occupied molecular orbital energy level of TzPyBr, excellent hole-blocking property of the electron-selective layer is also anticipated. The inverted organic photovoltaic devices based on the TzPyBr/ITO (indium tin oxide) bilayer cathode exhibit dramatically enhanced performance compared to the control devices with bare ITO as the cathode and even higher efficiency than the conventional type devices with ITO and Al as the electrodes.

  19. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    single-crystal devices, but rather low-end cells based on organic molecules or conducting polymers. Vital information for making organic solar cells more competitive for widespread...

  20. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    high-efficiency single-crystal devices, but rather low-end cells based on organic molecules or conducting polymers. Vital information for making organic solar cells more...

  1. High Efficiency Organic Solar Cells: December 16, 2009 - February 2, 2011

    SciTech Connect (OSTI)

    Walker, K.; Joslin, S.

    2011-05-01

    Details on the development of novel organic solar cells incorporating Trimetasphere based acceptors are presented including: baseline performance for Lu-PCBEH acceptor blended with P3HT demonstrated at 4.89% PCE exceeding the 4.5% PCE goal; an increase of over 250mV in Voc was demonstrated for Lu-PCBEH blended with low band gap polymers compared to a comparable C60-PCBM device. The actual Voc was certified at 260mV higher for a low band gap polymer device using the Lu-PCBEH acceptor; and the majority of the effort was focused on development of a device with over 7% PCE. While low current and fill factors suppressed overall device performance for the low band gap polymers tested, significant discoveries were made that point the way for future development of these novel acceptor materials.

  2. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic...

  3. Organic solvent vapor sensitive methylammonium lead trihalide film formation for efficient hybrid perovskite solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lian, Jiarong; Wang, Qi; Yuan, Yongbo; Shao, Yuchuan; Huang, Jinsong

    2015-03-25

    In this study, the anisotropic electronic properties of the perovskite crystals originating from their non-cubic crystal structures can potentially give rise to the grain orientation correlated photovoltaic device performance. Here we report that an organic solvent vapor atmosphere introduced during the spin-coating and formation of perovskite films changes the orientation and size of perovskite grains. It was found that slightly larger but much more oriented methylammonium lead trihalide (CH3NH3PbI3) grains could be obtained under 1,2-dichlorobenzene (DCB) and dimethyl sulfoxide (DMSO) vapor atmospheres. The devices with more oriented grains outperformed regular devices with more random grains by a 50 mV largermore » open circuit voltage as well as a slightly increased fill factor. The device efficiency enhancement can be attributed to the longer charge recombination lifetime resulting from the reduced trap density and oriented grains. This result is important in providing guidelines for comparing the results from various groups because organic solvent vapors are generally present in a sealed glovebox for perovskite solar cell fabrication.« less

  4. Organic Based Nanocomposite Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-04-145

    SciTech Connect (OSTI)

    Olson, D.

    2013-01-01

    This CRADA will focus on the development of organic-based solar cells. Key interfacial issues in these cells will be investigated. In this rapidly emerging technology, it is increasingly clear that cell architecture will need to be at the nanoscale and the interfacial issues between organic elements (small molecule and polymer), transparent conducting oxides, and contact metallizations are critical. Thus this work will focus on the development of high surface area and nanostructured nanocarpets of inorganic oxides, the development of appropriate surface binding/acceptor molecules for the inorganic/organic interface, and the development of next-generation organic materials. Work will be performed in all three areas jointly at NREL and Konarka (with their partner in the third area of the University of Delaware). Results should be more rapid progress toward cheap large-area photovoltaic cells.

  5. Ag-Pd-Cu alloy inserted transparent indium tin oxide electrodes for organic solar cells

    SciTech Connect (OSTI)

    Kim, Hyo-Joong; Seo, Ki-Won; Kim, Han-Ki, E-mail: imdlhkkim@khu.ac.kr [Department of Advanced Materials Engineering for Information and Electronics, Kyung-Hee University, 1 Seocheon-dong, Yongin-si, Gyeonggi-do 446-701 (Korea, Republic of); Noh, Yong-Jin; Na, Seok-In [Graduate School of Flexible and Printable Electronics, Chonbuk National University, 664-14, Deokjin-dong, Jeonju-si, Jeollabuk-do 561-756 (Korea, Republic of)

    2014-09-01

    The authors report on the characteristics of Ag-Pd-Cu (APC) alloy-inserted indium tin oxide (ITO) films sputtered on a glass substrate at room temperature for application as transparent anodes in organic solar cells (OSCs). The effect of the APC interlayer thickness on the electrical, optical, structural, and morphological properties of the ITO/APC/ITO multilayer were investigated and compared to those of ITO/Ag/ITO multilayer electrodes. At the optimized APC thickness of 8?nm, the ITO/APC/ITO multilayer exhibited a resistivity of 8.55?Ś?10{sup ?5} ? cm, an optical transmittance of 82.63%, and a figure-of-merit value of 13.54?Ś?10{sup ?3} ?{sup ?1}, comparable to those of the ITO/Ag/ITO multilayer. Unlike the ITO/Ag/ITO multilayer, agglomeration of the metal interlayer was effectively relieved with APC interlayer due to existence of Pd and Cu elements in the thin region of the APC interlayer. The OSCs fabricated on the ITO/APC/ITO multilayer showed higher power conversion efficiency than that of OSCs prepared on the ITO/Ag/ITO multilayer below 10?nm due to the flatness of the APC layer. The improved performance of the OSCs with ITO/APC/ITO multilayer electrodes indicates that the APC alloy interlayer prevents the agglomeration of the Ag-based metal interlayer and can decrease the thickness of the metal interlayer in the oxide-metal-oxide multilayer of high-performance OSCs.

  6. Photo annealing effect on p-doped inverted organic solar cell

    SciTech Connect (OSTI)

    Lafalce, Evan; Toglia, Patrick; Lewis, Jason E.; Jiang, Xiaomei

    2014-06-28

    We report the transient positive photo annealing effect in which over 600% boost of power conversion efficiency was observed in inverted organic photovoltaic devices (OPV) made from P3HT/PCBM by spray method, after 2?hrs of constant solar AM 1.5 irradiation at low temperature. This is opposite to usual photodegradation of OPV, and cannot be explained by thermal activation alone since the mere temperature effect could only account for 30% of the enhancement. We have investigated the temperature dependence, cell geometry, oxygen influence, and conclude that, for p-doped active layer at room temperature, the predominant mechanism is photo-desorption of O{sub 2}, which eliminates electron traps and reduces space charge screening. As temperature decreases, thermal activation and deep trap-state filling start to show noticeable effect on the enhancement of photocurrent at intermediate low temperature (T?=?125?K). At very low temperature, the dominant mechanism for photo annealing is trap-filling, which significantly reduces recombination between free and trapped carriers. At all temperature, photo annealing effect depends on illumination direction from cathode or anode. We also explained the large fluctuation of photocurrent by the capture/reemit of trapped electrons from shallow electron traps of O{sub 2}{sup -} generated by photo-doping. Our study has demonstrated the dynamic process of photo-doping and photo-desorption, and shown that photo annealing in vacuum can be an efficient method to improve OPV device efficiency.

  7. Solar cells

    DOE Patents [OSTI]

    Peumans, Peter; Uchida, Soichi; Forrest, Stephen R.

    2013-06-18

    Organic photosensitive optoelectronic devices are disclosed. The devises are thin-film crystalline organic optoelectronic devices capable of generating a voltage when exposed to light, and prepared by a method including the steps of: depositing a first organic layer over a first electrode; depositing a second organic layer over the first organic layer; depositing a confining layer over the second organic layer to form a stack; annealing the stack; and finally depositing a second electrode over the second organic layer.

  8. Increasing the efficiency of organic solar cells by photonic and electrostatic-field enhancements

    SciTech Connect (OSTI)

    Nalwa, Kanwar

    2012-11-03

    Organic photovoltaic (OPV) technology is an attractive solar-electric conversion paradigm due to the promise of low cost roll-to-roll production and amenability to flexible substrates. Power conversion efficiency (PCE) exceeding 7% has recently been achieved. OPV cells suffer from low charge carrier mobilities of polymers, leading to recombination losses, higher series resistances and lower fill-factors. Thus, it is imperative to develop fabrication methodologies that can enable efficient optical absorption in films thinner than optical absorption length. Active layers conformally deposited on light-trapping, microscale textured, grating-type surfaces is one possible approach to achieve this objective. In this study, 40% theoretical increase in photonic absorption over flat OPVs is shown for devices with textured geometry by the simulation results. For verifying this theoretical result and improving the efficiency of OPVs by light trapping, OPVs were fabricated on grating-type textured substrates possessing t pitch and -coat PV active-layer on these textured substrates led to over filling of the valleys and shunts at the crest, which severely affected the performance of the resultant PV devices. Thus, it is established that although the optical design is important for OPV performance but the potential of light trapping can only be effectively tapped if the textures are amenable for realizing a conformal active layer. It is discovered that if the height of the underlying topographical features is reduced to sub-micron regime (e.g. 300 nm) and the pitch is increased to more than a micron (e.g. 2 ?m), the textured surface becomes amenable to coating a conformal PV active-layer. The resultant PV cells showed 100% increase in average light absorption near the band edge due to trapping of higher wavelength photons, and 20% improvement in power conversion efficiency as compared with the flat PV cell. Another factor that severely limits the performance of OPVs is recombination of charge carriers. Thus it becomes imperative to understand the effect of processing conditions such as spin coating speed and drying rate on defect density and hence induced carrier recombination mechanism. In this study, It is shown that slow growth (longer drying time) of the active-layer leads to reduction of sub-bandgap traps by an order of magnitude as compared to fast grown active-layer. By coupling the experimental results with simulations, it is demonstrated that at one sun condition, slow grown device has bimolecular recombination as the major loss mechanism while in the fast grown device with high trap density, the trap assisted recombination dominates. It has been estimated that non-radiative recombination accounts nearly 50% of efficiency loss in modern OPVs. Generally, an external bias (electric field) is required to collect all the photogenerated charges and thus prevent their recombination. The motivation is to induce additional electric field in otherwise low mobility conjugated polymer based active layer by incorporating ferroelectric dipoles. This is expected to facilitate singlet exciton dissociation in polymer matrix and impede charge transfer exciton (CTE) recombination at polymer:fullerene interface. For the first time, it is shown that the addition of ferroelectric dipoles to modern bulk heterojunction (BHJ) can significantly improve exciton dissociation, resulting in a ~50% enhancement of overall solar cell efficiency. The devices also exhibit the unique ferroelectric-photovoltaic effect with polarization-controlled power conversion efficiency.

  9. Thermal annealing study on P3HT: PCBM based bulk heterojunction organic solar cells using impedance spectroscopy

    SciTech Connect (OSTI)

    Gollu, Sankara Rao; Sharma, Ramakant G, Srinivas Gupta, Dipti

    2014-10-15

    Recently, Thermal annealing is an important process for bulk heterojunction organic solar cells (BHJ OSCs) to improve the device efficiency and performance of the organic solar cells. Here in, we have examined the changes in the efficiency and morphology of P3HT: PCBM film according to the thermal annealing temperature to find the changes during the annealing process by measuring the optical absorption, atomic force microscope and X-ray diffraction. We also investigated the effect of different annealing process conditions (without, pre- and post-annealing) on the device performance of the inverted bulk heterojunction organic solar cells consist the structure of ITO/ ZnO / P3HT: PCBM / MoO{sub 3}/ Al by measuring AC impedance characteristics. Particularly, the power conversion efficiency (PCE), crystalline nature of the polymer, light absorption and the surface smoothness of P3HT: PCBM films are significantly improved after the annealing process. These results indicated the improvement in terms of PCE, interface smoothness between the P3HT: PCBM and MoO{sub 3} layers of the post annealed device originated from the decrease of series resistance between P3HT: PCBM layer and Al electrodes, which could be due to decrease in the effective life time of charge carriers.

  10. Modifying the organic/electrode interface in Organic Solar Cells (OSCs) and improving the efficiency of solution-processed phosphorescent Organic Light-Emitting Diodes (OLEDs)

    SciTech Connect (OSTI)

    Xiao, Teng

    2012-04-27

    Organic semiconductors devices, such as, organic solar cells (OSCs), organic light-emitting diodes (OLEDs) and organic field-effect transistors (OFETs) have drawn increasing interest in recent decades. As organic materials are flexible, light weight, and potentially low-cost, organic semiconductor devices are considered to be an alternative to their inorganic counterparts. This dissertation will focus mainly on OSCs and OLEDs. As a clean and renewable energy source, the development of OSCs is very promising. Cells with 9.2% power conversion efficiency (PCE) were reported this year, compared to < 8% two years ago. OSCs belong to the so-called third generation solar cells and are still under development. While OLEDs are a more mature and better studied field, with commercial products already launched in the market, there are still several key issues: (1) the cost of OSCs/OLEDs is still high, largely due to the costly manufacturing processes; (2) the efficiency of OSCs/OLEDs needs to be improved; (3) the lifetime of OSCs/OLEDs is not sufficient compared to their inorganic counterparts; (4) the physics models of the behavior of the devices are not satisfactory. All these limitations invoke the demand for new organic materials, improved device architectures, low-cost fabrication methods, and better understanding of device physics. For OSCs, we attempted to improve the PCE by modifying the interlayer between active layer/metal. We found that ethylene glycol (EG) treated poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT: PSS) improves hole collection at the metal/polymer interface, furthermore it also affects the growth of the poly(3- hexylthiophene) (P3HT):phenyl-C61-butyric acid methyl ester (PCBM) blends, making the phase segregation more favorable for charge collection. We then studied organic/inorganic tandem cells. We also investigated the effect of a thin LiF layer on the hole-collection of copper phthalocyanine (CuPc)/C70-based small molecular OSCs. A thin LiF layer serves typically as the electron injection layer in OLEDs and electron collection interlayer in the OSCs. However, several reports showed that it can also assist in holeinjection in OLEDs. Here we first demonstrate that it assists hole-collection in OSCs, which is more obvious after air-plasma treatment, and explore this intriguing dual role. For OLEDs, we focus on solution processing methods to fabricate highly efficient phosphorescent OLEDs. First, we investigated OLEDs with a polymer host matrix, and enhanced charge injection by adding hole- and electron-transport materials into the system. We also applied a hole-blocking and electron-transport material to prevent luminescence quenching by the cathode. Finally, we substituted the polymer host by a small molecule, to achieve more efficient solution processed small molecular OLEDs (SMOLEDs); this approach is cost-effective in comparison to the more common vacuum thermal evaporation. All these studies help us to better understand the underlying relationship between the organic semiconductor materials and the OSCs and OLEDs’ performance and will subsequently assist in further enhancing the efficiencies of OSCs and OLEDs. With better efficiency and longer lifetime, the OSCs and OLEDs will be competitive with their inorganic counterparts.

  11. Fabrication and characterization of inverted organic solar cells using shuttle cock-type metal phthalocyanine and PCBM:P3HT

    SciTech Connect (OSTI)

    Suzuki, Atsushi Furukawa, Ryo Akiyama, Tsuyoshi Oku, Takeo

    2015-02-27

    Inverted organic solar cells using shuttle cock-type phthalocyanine, semiconducting polymer and fullerenes were fabricated and characterized. Photovoltaic and optical properties of the solar cells with inverted structures were investigated by optical absorption, current density-voltage characteristics. The photovoltaic properties of the tandem organic solar cell using titanyl phthalocyanine, vanadyl phthalocyanine, poly(3-hexylthiophene) (P3HT) and [6, 6]-phenyl C{sub 61}-butyric acid methyl ester (PCBM) were improved. Effect of annealing and solvent treatment on surface morphologies of the active layer was investigated. The photovoltaic mechanisms, energy levels and band gap of active layers were discussed for improvement of the photovoltaic performance.

  12. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Structure of All-Polymer Solar Cells Impedes Efficiency Print Wednesday, 27 October 2010 00:00 Organic solar cells are made...

  13. Photovoltaic properties and morphology of organic solar cells based on liquid-crystal semiconducting polymer with additive

    SciTech Connect (OSTI)

    Suzuki, Atsushi; Zushi, Masahito; Suzuki, Hisato; Ogahara, Shinichi; Akiyama, Tsuyoshi; Oku, Takeo

    2014-02-20

    Bulk heterojunction organic solar cell based on liquid crystal semiconducting polymers of poly[9,9-dioctylfluorene-co-bithiophene] (F8T2) as p-type semiconductors and fullerenes (C{sub 60}) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as electron donor and acceptor has been fabricated and characterized for improving photovoltaic and optical properties. The photovoltaic performance including current voltage curves in the dark and illumination of the F8T2/C{sub 60} conventional and inverted bulk heterojunction solar cells were investigated. Relationship between the photovoltaic properties and morphological behavior was focused on tuning for optimization of photo-voltaic performance under annealing condition near glass transition temperature. Additive-effect of diiodooctane (DIO) and poly(3-hexylthiophene-2,5-diyl) (P3HT) on the photovoltaic performance and optical properties was investigated. Mechanism of the photovoltaic properties of the conventional and inverted solar cells will be discussed by the experimental results.

  14. Polydimethylsiloxane as a Macromolecular Additive for Enhanced Performance of Molecular Bulk Heterojunction Organic Solar Cells

    SciTech Connect (OSTI)

    Graham, Kenneth R.; Mei, Jianguo; Stalder, Romain; Shim, Jae Won; Cheun, Hyeunseok; Steffy, Fred; So, Franky; Kippelen, Bernard; Reynolds, John R.

    2011-03-15

    The effect of the macromolecular additive, polydimethylsiloxane (PDMS), on the performance of solution processed molecular bulk heterojunction solar cells is investigated, and the addition of PDMS is shown to improve device power conversion efficiency by ~70% and significantly reduce cell-to-cell variation, from a power conversion efficiency of 1.25 ± 0.37% with no PDMS to 2.16 ± 0.09% upon the addition of 0.1 mg/mL PDMS to the casting solution. The cells are based on a thiophene and isoindigo containing oligomer as the electron donor and [6,6]-phenyl-C61 butyric acid methyl ester (PC61BM) as the electron acceptor. PDMS is shown to have a strong influence on film morphology, with a significant decrease in film roughness and feature size observed. The morphology change leads to improved performance parameters, most notably an increase in the short circuit current density from 4.3 to 6.8 mA/cm2 upon addition of 0.1 mg/mL PDMS. The use of PDMS is of particular interest, as this additive appears frequently as a lubricant in plastic syringes commonly used in device fabrication; therefore, PDMS may unintentionally be incorporated into device active layers.

  15. Photovoltaic solar cell

    DOE Patents [OSTI]

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2015-09-08

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  16. Heterojunction solar cell

    DOE Patents [OSTI]

    Olson, Jerry M. (Lakewood, CO)

    1994-01-01

    A high-efficiency single heterojunction solar cell wherein a thin emitter layer (preferably Ga.sub.0.52 In.sub.0.48 P) forms a heterojunction with a GaAs absorber layer. The conversion effiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the emitter layer.

  17. Heterojunction solar cell

    DOE Patents [OSTI]

    Olson, J.M.

    1994-08-30

    A high-efficiency single heterojunction solar cell is described wherein a thin emitter layer (preferably Ga[sub 0.52]In[sub 0.48]P) forms a heterojunction with a GaAs absorber layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the emitter layer. 1 fig.

  18. Spectral sensitization of nanocrystalline solar cells

    DOE Patents [OSTI]

    Spitler, Mark T. (Concord, MA); Ehret, Anne (Malden, MA); Stuhl, Louis S. (Bedford, MA)

    2002-01-01

    This invention relates to dye sensitized polycrystalline photoelectrochemical solar cells for use in energy transduction from light to electricity. It concerns the utility of highly absorbing organic chromophores as sensitizers in such cells and the degree to which they may be utilized alone and in combination to produce an efficient photoelectrochemical cell, e.g., a regenerative solar cell.

  19. Innotech Solar AS formerly known as Solar Cell Repower | Open...

    Open Energy Info (EERE)

    Innotech Solar AS formerly known as Solar Cell Repower Jump to: navigation, search Name: Innotech Solar AS (formerly known as Solar Cell Repower) Place: Narvik, Norway Zip: 8512...

  20. A low-temperature processed environment-friendly full-organic carrier collection layer for polymer solar cells

    SciTech Connect (OSTI)

    Shi, Ai-Li; Li, Yan-Qing E-mail: zhangdd@suda.edu.cn Jiang, Xiao-Chen; Ma, Zhong-Sheng; Wang, Qian-Kun; Guo, Zhen-Yu; Zhang, Dan-Dan E-mail: zhangdd@suda.edu.cn Lee, Shuit-Tong; Tang, Jian-Xin E-mail: zhangdd@suda.edu.cn

    2014-08-04

    We constructed a concept of the full-organic carrier collection layer (CCL) used for polymer solar cells. The CCL is composed of dipyrazino[2,3-f:2?,3?-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile as hole collection layer (HCL) and chlorine-free solvents (formic acid (FA)) processed 4,7-Diphenyl-1,10-phenanthroline (Bphen) as electron collection layer, exhibiting good solubility, and environmental protection. The FA based device shows ideal power conversion efficiency (3.75%), which is higher than that of control device (3.6%). Besides, the HCL shows a different mechanism in hole extraction by functioning as a charge recombination zone for electrons injected from anode and holes extracted from the donor materials.

  1. Solar Cells | Open Energy Information

    Open Energy Info (EERE)

    Solar Cells Place: Split, Croatia Zip: 21000 Product: manufacturers of PV modules References: Solar Cells1 This article is a stub. You can help OpenEI by expanding it. Solar...

  2. Solar cell array interconnects

    DOE Patents [OSTI]

    Carey, P.G.; Thompson, J.B.; Colella, N.J.; Williams, K.A.

    1995-11-14

    Electrical interconnects are disclosed for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value. 4 figs.

  3. Solar cell array interconnects

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Thompson, Jesse B. (Brentwood, CA); Colella, Nicolas J. (Livermore, CA); Williams, Kenneth A. (Livermore, CA)

    1995-01-01

    Electrical interconnects for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value.

  4. Photovoltaic solar cell

    DOE Patents [OSTI]

    Nielson, Gregory N; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J

    2014-05-20

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electricity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  5. Photovoltaic solar cell

    DOE Patents [OSTI]

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  6. Mechanism of charge recombination in meso-structured organic-inorganic hybrid perovskite solar cells: A macroscopic perspective

    SciTech Connect (OSTI)

    Yang, Wenchao; Yao, Yao Wu, Chang-Qin

    2015-04-21

    In the currently popular organic-inorganic hybrid perovskite solar cells, the slowness of the charge recombination processes is found to be a key factor for contributing to their high efficiencies and high open circuit voltages, but the underlying recombination mechanism remains unclear. In this work, we investigate the bimolecular recombination (BR) and the trap-assisted monomolecular recombination (MR) in meso-structured perovskite solar cells under steady state working condition, and try to reveal their roles on determining the device performance. Some interfacial effects such as the injection barriers at the selective contacts are examined as well. Based on the macroscopic device modeling, the recombination resistance-voltage (R{sub rec}?V) and the current density-voltage (J–V) curves are calculated to characterize the recombination mechanism and describe the device performance, respectively. Through comparison with the impedance spectroscopy extracted R{sub rec} data, it is found that under the typical BR reduction factor and deep trap densities observed in experiments, the MR dominates the charge recombination in the low voltage regime, while the BR dominates in the high voltage regime. The short circuit current and the fill factor could be reduced by the significant MR but the open circuit voltage is generally determined by the BR. The different electron injection barriers at the contact can change the BR rate and induce different patterns for the R{sub rec}–V characteristics. For the perovskites of increased band gaps, the R{sub rec}'s are significantly enhanced, corresponding to the high open circuit voltages. Finally, it is revealed that the reduced effective charge mobility due to the transport in electron and hole transporting material makes the R{sub rec} decrease slowly with the increasing voltage, which leads to increased open circuit voltage.

  7. Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Investigation Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical Investigation Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical Investigation Print Wednesday, 03 April 2013 13:32 Spin-coating is extensively used in the lab-based manufacturing of organic solar cells, including most of the record-setting cells. Aram Amassian and co-workers report in this study the first direct observation of photoactive layer formation as it occurs during spin-coating. The

  8. Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical Investigation Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical Investigation Print Wednesday,...

  9. Broad spectrum solar cell

    DOE Patents [OSTI]

    Walukiewicz, Wladyslaw (Kensington, CA); Yu, Kin Man (Lafayette, CA); Wu, Junqiao (Richmond, CA); Schaff, William J. (Ithaca, NY)

    2007-05-15

    An alloy having a large band gap range is used in a multijunction solar cell to enhance utilization of the solar energy spectrum. In one embodiment, the alloy is In.sub.1-xGa.sub.xN having an energy bandgap range of approximately 0.7 eV to 3.4 eV, providing a good match to the solar energy spectrum. Multiple junctions having different bandgaps are stacked to form a solar cell. Each junction may have different bandgaps (realized by varying the alloy composition), and therefore be responsive to different parts of the spectrum. The junctions are stacked in such a manner that some bands of light pass through upper junctions to lower junctions that are responsive to such bands.

  10. Computational Challenges for Nanostructure Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Challenges for Nanostructure Solar Cells Computational Challenges for Nanostructure Solar Cells ZZ2.jpg Key Challenges: Current nanostructure solar cells often have energy...

  11. Monolithic tandem solar cell

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO)

    1991-01-01

    A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surface of the InP substrate, and (c) a second photoactive subcell on the first subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched. The solar cell can be provided as a two-terminal device or a three-terminal device.

  12. TJ Solar Cell

    SciTech Connect (OSTI)

    Friedman, Daniel

    2009-04-17

    This talk will discuss recent developments in III-V multijunction photovoltaic technology which have led to the highest-efficiency solar cells ever demonstrated. The relationship between the materials science of III-V semiconductors and the achievement of record solar cell efficiencies will be emphasized. For instance, epitaxially-grown GAInP has been found to form a spontaneously-ordered GaP/InP (111) superlattice. This ordering affects the band gap of the material, which in turn affects the design of solar cells which incorporate GaInP. For the next generation of ultrahigh-efficiency III-V solar cells, we need a new semiconductor which is lattice-matched to GaAs, has a band gap of 1 eV, and has long minority-carrier diffusion lengths. Out of a number of candidate materials, the recently-discovered alloy GaInNAs appears to have the greatest promise. This material satisfies the first two criteria, but has to date shown very low diffusion lengths, a problem which is our current focus in the development of these next-generation cells.

  13. The influence of molecular orientation on organic bulk heterojunction solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    cells The influence of molecular orientation on organic bulk heterojunction solar cells The influence of molecular orientation on organic bulk heterojunction solar cells Print Monday, 28 April 2014 09:03 Work done on ALS Beamlines 11.0.1.2, 7.3.3, and 5.3.2.2. reveals that preferential orientation of polymer chains with respect to the fullerene domain leads to a high photovoltaic performance. Featured on the cover of Nature Photonics 8. Article link

  14. Solar Cell Simulation

    K-12 Energy Lesson Plans and Activities Web site (EERE)

    Students model the flow of energy from the sun as it enters a photovoltaic cell, moves along a wire and powers a load. The game-like atmosphere involves the younger students and helps them understand the continuous nature of the flow of energy. For a related lesson, please see the activity “Solar Powered System” (PDF 430 KB).

  15. Amorphous semiconductor solar cell

    DOE Patents [OSTI]

    Dalal, Vikram L. (Newark, DE)

    1981-01-01

    A solar cell comprising a back electrical contact, amorphous silicon semiconductor base and junction layers and a top electrical contact includes in its manufacture the step of heat treating the physical junction between the base layer and junction layer to diffuse the dopant species at the physical junction into the base layer.

  16. Correlating High Power Conversion Efficiency of PTB7:PC71BM Inverted Organic Solar Cells with Nanoscale Structures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Das, Sanjib; Keum, Jong Kahk; Browning, Jim; Gu, Gong; Yang, Bin; Do, Changwoo; Chen, Wei; Chen, Jihua; Ivanov, Ilia N; Hong, Kunlun; et al

    2015-07-16

    Advances in materials design and device engineering led to inverted organic solar cells (i-OSCs) with superior power conversion efficiencies (PCEs) to their conventional counterparts, in addition to the well-known better ambient stability. Despite the significant progress, however, it has so far been unclear how the morphologies of the photoactive layer and its interface with the cathode modifying layer impact device performance. Here, we report an in-depth morphology study of the i-OSC active and cathode modifying layers, employing a model system with the well-established bulk-heterojunction, PTB7:PC71BM as the active layer and poly-[(9,9-bis(3 -(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as the cathode surface modifying layer. Wemore » have also identified the role of a processing additive, 1,8-diiodooctane (DIO), used in the spin-casting of the active layer to increase PCE. Using a variety of characterization techniques, we demonstrate that the high PCEs of i-OSCs are due to the smearing (diffusion) of electron-accepting PC71BM into the PFN layer, resulting in improved electron transport. The PC71BM diffusion occurs after spin-casting the active layer onto the PFN layer, when residual solvent molecules act as a plasticizer. The DIO additive, with a higher boiling point than the host solvent, has a longer residence time in the spin-cast active layer, resulting in more PC71BM smearing and therefore more efficient electron transport. This work provides important insight and guidance to further enhancement of i-OSC performance by materials and interface engineering.« less

  17. Correlating High Power Conversion Efficiency of PTB7:PC71BM Inverted Organic Solar Cells to Nanoscale Structure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Das, Sanjib; Keum, Jong Kahk; Browning, Jim; Gu, Gong; Yang, Bin; Do, Changwoo; Chen, Wei; Chen, Jihua; Ivanov, Ilia N; Hong, Kunlun; et al

    2015-07-16

    Advances in materials design and device engineering led to inverted organic solar cells (i-OSCs) with superior power conversion efficiencies (PCEs) to their conventional counterparts, in addition to the well-known better ambient stability. Despite the significant progress, however, it has so far been unclear how the morphologies of the photoactive layer and its interface with the cathode modifying layer impact device performance. Here, we report an in-depth morphology study of the i-OSC active and cathode modifying layers, employing a model system with the well-established bulk-heterojunction, PTB7:PC71BM as the active layer and poly-[(9,9-bis(3 -(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as the cathode surface modifying layer. Wemore »have also identified the role of a processing additive, 1,8-diiodooctane (DIO), used in the spin-casting of the active layer to increase PCE. Using a variety of characterization techniques, we demonstrate that the high PCEs of i-OSCs are due to the smearing (diffusion) of electron-accepting PC71BM into the PFN layer, resulting in improved electron transport. The PC71BM diffusion occurs after spin-casting the active layer onto the PFN layer, when residual solvent molecules act as a plasticizer. The DIO additive, with a higher boiling point than the host solvent, has a longer residence time in the spin-cast active layer, resulting in more PC71BM smearing and therefore more efficient electron transport. This work provides important insight and guidance to further enhancement of i-OSC performance by materials and interface engineering.« less

  18. Leakage pathway layer for solar cell

    SciTech Connect (OSTI)

    Luan, Andy; Smith, David; Cousins, Peter; Sun, Sheng

    2015-12-01

    Leakage pathway layers for solar cells and methods of forming leakage pathway layers for solar cells are described.

  19. Solar Cells Hellas SA | Open Energy Information

    Open Energy Info (EERE)

    Cells Hellas SA Jump to: navigation, search Name: Solar Cells Hellas SA Place: Athens, Greece Product: Greek manufacturer of PV wafers, cells and modules. References: Solar Cells...

  20. Monolithic tandem solar cell

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO)

    1994-01-01

    A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surface of the InP substrate, (c) a second photoactive subcell on the first subcell; and (d) an optically transparent prismatic cover layer over the second subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched.

  1. Monolithic tandem solar cell

    DOE Patents [OSTI]

    Wanlass, M.W.

    1994-06-21

    A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surface of the InP substrate, (c) a second photoactive subcell on the first subcell; and (d) an optically transparent prismatic cover layer over the second subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched. 9 figs.

  2. World's Most Efficient Solar Cell

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    World's Most Efficient Solar Cell National Renewable Energy Laboratory, Spectrolab Set Record For more information contact: George Douglas, 303-275-4096 e:mail: George Douglas Golden, Colo., Nov. 1, 1999 - A solar cell that can convert sunlight to electricity at a record-setting 32 percent efficiency has been developed by the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) and Spectrolab. The high efficiency makes the cells attractive for use in solar concentrator

  3. Solar cell module lamination process

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Thompson, Jesse B. (Brentwood, CA); Aceves, Randy C. (Tracy, CA)

    2002-01-01

    A solar cell module lamination process using fluoropolymers to provide protection from adverse environmental conditions and thus enable more extended use of solar cells, particularly in space applications. A laminate of fluoropolymer material provides a hermetically sealed solar cell module structure that is flexible and very durable. The laminate is virtually chemically inert, highly transmissive in the visible spectrum, dimensionally stable at temperatures up to about 200.degree. C. highly abrasion resistant, and exhibits very little ultra-violet degradation.

  4. NREL: Solar Research - Potential of Perovskite Solar Cells Featured in

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Today Potential of Perovskite Solar Cells Featured in Solar Today February 11, 2016 Familiar with perovskite solar cells? If not, you'll probably hear more about them soon. Perovskites are a family of materials receiving considerable attention by solar cell researchers due to the rapid rise of solar conversion efficiencies, increasing from about 4% to almost 22% in just six years. In an interview published in Solar Today (winter 2015 edition), Dr. Jao van de Lagemaat, director of the

  5. Plastic Schottky-barrier solar cells

    DOE Patents [OSTI]

    Waldrop, J.R.; Cohen, M.J.

    1981-12-30

    A photovoltaic cell structure is fabricated from an active medium including an undoped polyacetylene, organic semiconductor. When a film of such material is in rectifying contact with a metallic area electrode, a Schottky-barrier junction is obtained within the body of the cell structure. Also, a gold overlayer passivates a magnesium layer on the undoped polyacetylene film. With the proper selection and location of elements a photovoltaic cell structure and solar cell are obtained.

  6. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Structure of All-Polymer Solar Cells Impedes Efficiency Print Wednesday, 27 October 2010 00:00 Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same

  7. Potential of Perovskite Solar Cells Featured in Solar Today | Community |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL Potential of Perovskite Solar Cells Featured in Solar Today February 11, 2016 Familiar with perovskite solar cells? If not, you'll probably hear more about them soon. Perovskites are a family of materials receiving considerable attention by solar cell researchers due to the rapid rise of solar conversion efficiencies, increasing from about 4% to almost 22% in just six years. In an interview published in Solar Today (winter 2015 edition), Dr. Jao van de Lagemaat, director of the

  8. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell...

  9. Research highlights potential for improved solar cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Potential for improved solar cells Research highlights potential for improved solar cells Research has shown that carrier multiplication is a real phenomenon in tiny semiconductor...

  10. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption....

  11. Energy level alignment in polymer organic solar cells at donor-acceptor planar junction formed by electrospray vacuum deposition

    SciTech Connect (OSTI)

    Kim, Ji-Hoon; Hong, Jong-Am; Kwon, Dae-Gyeon; Seo, Jaewon; Park, Yongsup

    2014-04-21

    Using ultraviolet photoelectron spectroscopy (UPS), we have measured the energy level offset at the planar interface between poly(3-hexylthiophene) (P3HT) and C{sub 61}-butyric acid methylester (PCBM). Gradual deposition of PCBM onto spin-coated P3HT in high vacuum was made possible by using electrospray vacuum deposition (EVD). The UPS measurement of EVD-prepared planar interface resulted in the energy level offset of 0.91?eV between P3HT HOMO and PCBM LUMO, which is considered as the upper limit of V{sub oc} of the organic photovoltaic cells.

  12. Multiple Exciton Generation Solar Cells

    SciTech Connect (OSTI)

    Luther, J. M.; Semonin, O. E.; Beard, M. C.; Gao, J.; Nozik, A. J.

    2012-01-01

    Heat loss is the major factor limiting traditional single junction solar cells to a theoretical efficiency of 32%. Multiple Exciton Generation (MEG) enables efficient use of the solar spectrum yielding a theoretical power conversion efficiency of 44% in solar cells under 1-sun conditions. Quantum-confined semiconductors have demonstrated the ability to generate multiple carriers but present-day materials deliver efficiencies far below the SQ limit of 32%. Semiconductor quantum dots of PbSe and PbS provide an active testbed for developing high-efficiency, inexpensive solar cells benefitting from quantum confinement effects. Here, we will present recent work of solar cells employing MEG to yield external quantum efficiencies exceeding 100%.

  13. Process for Fabrication of Efficient Solar Cells - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Process for Fabrication of Efficient Solar Cells Ames Laboratory Contact AMES About This Technology Technology Marketing Summary Ames Laboratory researchers have developed a process for fabrication of solar cells with increased efficiency. Description Polymer-based photovoltaic devices have received intense interest in recent years because of their potential to provide low-cost solar energy conversion, flexibility, manufacturability, and are light weight. However, the efficiency of organic solar

  14. Optical and carrier transport properties of graphene oxide based crystalline-Si/organic Schottky junction solar cells

    SciTech Connect (OSTI)

    Khatri, I.; Tang, Z.; Hiate, T.; Liu, Q.; Ishikawa, R.; Ueno, K.; Shirai, H.

    2013-12-21

    We investigated the graphene oxide (GO) based n-type crystalline silicon (c-Si)/conductive poly(ethylene dioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) Schottky junction devices with optical characterization and carrier transport measurement techniques. The optical transmittance in the UV region decreased markedly for the films with increasing the concentration of GO whereas it increased markedly in the visible-infrared regions. Spectroscopic ellipsometry revealed that the ordinary and extraordinary index of refraction increased with increasing the concentration of GO. The hole mobility also increased from 1.14 for pristine film to 1.85 cm{sup 2}/V s for the 12–15?wt. % GO modified film with no significant increases of carrier concentration. The highest conductivity was found for a 15?wt. % GO modified PEDOT:PSS film: the c-Si/PEDOT:PSS:GO device using this sample exhibited a relatively high power conversion efficiency of 11.04%. In addition, the insertion of a 2–3?nm-thick GO thin layer at the c-Si/PEDOT:PSS interface suppressed the carrier recombination efficiency of dark electron and photo-generated hole at the anode, resulting in the increased photovoltaic performance. This study indicates that the GO can be good candidates for hole transporting layer of c-Si/PEDOT:PSS Schottky junction solar cell.

  15. Energetic Barrier Prevents Recombination in Organic Solar Photoconversion Systems (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-08-01

    NREL researchers unravel the factors that affect charge generation and loss in high-performance conjugated polymer-fullerene blends used in organic solar cells.

  16. Module level solutions to solar cell polarization

    DOE Patents [OSTI]

    Xavier, Grace (Fremont, CA), Li; Bo (San Jose, CA)

    2012-05-29

    A solar cell module includes interconnected solar cells, a transparent cover over the front sides of the solar cells, and a backsheet on the backsides of the solar cells. The solar cell module includes an electrical insulator between the transparent cover and the front sides of the solar cells. An encapsulant protectively packages the solar cells. To prevent polarization, the insulator has resistance suitable to prevent charge from leaking from the front sides of the solar cells to other portions of the solar cell module by way of the transparent cover. The insulator may be attached (e.g., by coating) directly on an underside of the transparent cover or be a separate layer formed between layers of the encapsulant. The solar cells may be back junction solar cells.

  17. Un-Nanostructuring Solar Cells | ANSER Center | Argonne-Northwestern...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Un-Nanostructuring Solar Cells Home > Research > ANSER Research Highlights > Un-Nanostructuring Solar Cells...

  18. Nanoparticle Solar Cell Final Technical Report

    SciTech Connect (OSTI)

    Breeze, Alison, J; Sahoo, Yudhisthira; Reddy, Damoder; Sholin, Veronica; Carter, Sue

    2008-06-17

    The purpose of this work was to demonstrate all-inorganic nanoparticle-based solar cells with photovoltaic performance extending into the near-IR region of the solar spectrum as a pathway towards improving power conversion efficiencies. The field of all-inorganic nanoparticle-based solar cells is very new, with only one literature publication in the prior to our project. Very little is understood regarding how these devices function. Inorganic solar cells with IR performance have previously been fabricated using traditional methods such as physical vapor deposition and sputtering, and solution-processed devices utilizing IR-absorbing organic polymers have been investigated. The solution-based deposition of nanoparticles offers the potential of a low-cost manufacturing process combined with the ability to tune the chemical synthesis and material properties to control the device properties. This work, in collaboration with the Sue Carter research group at the University of California, Santa Cruz, has greatly expanded the knowledge base in this field, exploring multiple material systems and several key areas of device physics including temperature, bandgap and electrode device behavior dependence, material morphological behavior, and the role of buffer layers. One publication has been accepted to Solar Energy Materials and Solar Cells pending minor revision and another two papers are being written now. While device performance in the near-IR did not reach the level anticipated at the beginning of this grant, we did observe one of the highest near-IR efficiencies for a nanoparticle-based solar cell device to date. We also identified several key parameters of importance for improving both near-IR performance and nanoparticle solar cells in general, and demonstrated multiple pathways which showed promise for future commercialization with further research.

  19. Solar cell with back side contacts

    DOE Patents [OSTI]

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

    2013-12-24

    A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

  20. Plastic Solar Cells See Bright Future | ANSER Center | Argonne...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plastic Solar Cells See Bright Future Home > News & Events > Plastic Solar Cells See Bright Future Plastic Solar Cells See Bright Future Evanston, Ill---Energy consumption is ...

  1. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  2. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  3. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  4. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  5. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  6. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  7. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  8. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  9. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Structure of All-Polymer Solar Cells Impedes Efficiency Print Organic solar cells are made of thin layers of interpenetrating structures from two different conducting organic materials and are increasingly popular because they are both potentially cheaper to make than those currently in use and can be "painted" or printed onto a variety of surfaces, including flexible films made from the same material as most soda bottles. A large community is exploring a number of promising material

  10. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce...

  11. Compensated amorphous silicon solar cell

    DOE Patents [OSTI]

    Carlson, David E. (Yardley, PA)

    1980-01-01

    An amorphous silicon solar cell incorporates a region of intrinsic hydrogenated amorphous silicon fabricated by a glow discharge wherein said intrinsic region is compensated by P-type dopants in an amount sufficient to reduce the space charge density of said region under illumination to about zero.

  12. Key Physical Mechanisms in Nanostructured Solar Cells

    SciTech Connect (OSTI)

    Dr Stephan Bremner

    2010-07-21

    The objective of the project was to study both theoretically and experimentally the excitation, recombination and transport properties required for nanostructured solar cells to deliver energy conversion efficiencies well in excess of conventional limits. These objectives were met by concentrating on three key areas, namely, investigation of physical mechanisms present in nanostructured solar cells, characterization of loss mechanisms in nanostructured solar cells and determining the properties required of nanostructured solar cells in order to achieve high efficiency and the design implications.

  13. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  14. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  15. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  16. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  17. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Biomimetic Dye Molecules for Solar Cells Print Wednesday, 28 April 2010 00:00 Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most

  18. Pokeberries Provide Boost for Solar Cells

    Broader source: Energy.gov [DOE]

    Red dye from the pokeberry weed makes their low-cost, fiber-based solar cells even more energy efficient.

  19. Process of making solar cell module

    DOE Patents [OSTI]

    Packer, M.; Coyle, P.J.

    1981-03-09

    A process is presented for the manufacture of solar cell modules. A solution comprising a highly plasticized polyvinyl butyral is applied to a solar cell array. The coated array is dried and sandwiched between at last two sheets of polyvinyl butyral and at least two sheets of a rigid transparent member. The sandwich is laminated by the application of heat and pressure to cause fusion and bonding of the solar cell array with the rigid transparent members to produce a solar cell module.

  20. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  1. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  2. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  3. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  4. When Function Follows Form: Plastic Solar Cells | ANSER Center...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    When Function Follows Form: Plastic Solar Cells Home > Research > ANSER Research Highlights > When Function Follows Form: Plastic Solar Cells...

  5. Ames Lab 101: Improving Solar Cell Efficiency

    ScienceCinema (OSTI)

    Biswas, Rana

    2012-08-29

    Rana Biswas, a scientist with the Ames Laboratory, discusses his team's research in creating more efficient solar cells and working with Iowa Thin Film to produce these cells.

  6. Mixed ternary heterojunction solar cell

    DOE Patents [OSTI]

    Chen, Wen S.; Stewart, John M.

    1992-08-25

    A thin film heterojunction solar cell and a method of making it has a p-type layer of mixed ternary I-III-VI.sub.2 semiconductor material in contact with an n-type layer of mixed binary II-VI semiconductor material. The p-type semiconductor material includes a low resistivity copper-rich region adjacent the back metal contact of the cell and a composition gradient providing a minority carrier mirror that improves the photovoltaic performance of the cell. The p-type semiconductor material preferably is CuInGaSe.sub.2 or CuIn(SSe).sub.2.

  7. Tianjin Jinneng Solar Cell Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Solar Cell Co Ltd Jump to: navigation, search Name: Tianjin Jinneng Solar Cell Co Ltd Place: Tianjin Municipality, China Zip: 300384 Sector: Solar Product: Chinese manufacturer of...

  8. Enabling Thin Silicon Solar Cell Technology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enabling Thin Silicon Solar Cell Technology Enabling Thin Silicon Solar Cell Technology Print Friday, 21 June 2013 10:49 Generic silicon solar cells showing +45°, -45°, and dendritic crack patterns. The effort to shift U.S. energy reliance from fossil fuels to renewable sources has spurred companies to reduce the cost and increase the reliability of their solar photovoltaics (SPVs). The use of thinner silicon in SPV technologies is being widely adopted because it significantly reduces costs;

  9. Compensated amorphous silicon solar cell

    DOE Patents [OSTI]

    Devaud, Genevieve (629 S. Humphrey Ave., Oak Park, IL 60304)

    1983-01-01

    An amorphous silicon solar cell including an electrically conductive substrate, a layer of glow discharge deposited hydrogenated amorphous silicon over said substrate and having regions of differing conductivity with at least one region of intrinsic hydrogenated amorphous silicon. The layer of hydrogenated amorphous silicon has opposed first and second major surfaces where the first major surface contacts the electrically conductive substrate and an electrode for electrically contacting the second major surface. The intrinsic hydrogenated amorphous silicon region is deposited in a glow discharge with an atmosphere which includes not less than about 0.02 atom percent mono-atomic boron. An improved N.I.P. solar cell is disclosed using a BF.sub.3 doped intrinsic layer.

  10. Spatiotemporal organization of energy release events in the quiet solar

    Office of Scientific and Technical Information (OSTI)

    corona (Journal Article) | SciTech Connect Spatiotemporal organization of energy release events in the quiet solar corona Citation Details In-Document Search Title: Spatiotemporal organization of energy release events in the quiet solar corona Using data from the STEREO and SOHO spacecraft, we show that temporal organization of energy release events in the quiet solar corona is close to random, in contrast to the clustered behavior of flaring times in solar active regions. The locations of

  11. Three-junction solar cell

    DOE Patents [OSTI]

    Ludowise, Michael J. (Cupertino, CA)

    1986-01-01

    A photovoltaic solar cell is formed in a monolithic semiconductor. The cell contains three junctions. In sequence from the light-entering face, the junctions have a high, a medium, and a low energy gap. The lower junctions are connected in series by one or more metallic members connecting the top of the lower junction through apertures to the bottom of the middle junction. The upper junction is connected in voltage opposition to the lower and middle junctions by second metallic electrodes deposited in holes 60 through the upper junction. The second electrodes are connected to an external terminal.

  12. Correlating High Power Conversion Efficiency of PTB7:PC71BM Inverted Organic Solar Cells with Nanoscale Structures

    SciTech Connect (OSTI)

    Das, Sanjib; Keum, Jong Kahk; Browning, Jim; Gu, Gong; Yang, Bin; Do, Changwoo; Chen, Wei; Chen, Jihua; Ivanov, Ilia N; Hong, Kunlun; Rondinone, Adam J.; Joshi, Pooran C.; Geohegan, David B.; Xiao, Kai

    2015-07-16

    Advances in materials design and device engineering led to inverted organic solar cells (i-OSCs) with superior power conversion efficiencies (PCEs) to their conventional counterparts, in addition to the well-known better ambient stability. Despite the significant progress, however, it has so far been unclear how the morphologies of the photoactive layer and its interface with the cathode modifying layer impact device performance. Here, we report an in-depth morphology study of the i-OSC active and cathode modifying layers, employing a model system with the well-established bulk-heterojunction, PTB7:PC71BM as the active layer and poly-[(9,9-bis(3 -(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as the cathode surface modifying layer. We have also identified the role of a processing additive, 1,8-diiodooctane (DIO), used in the spin-casting of the active layer to increase PCE. Using a variety of characterization techniques, we demonstrate that the high PCEs of i-OSCs are due to the smearing (diffusion) of electron-accepting PC71BM into the PFN layer, resulting in improved electron transport. The PC71BM diffusion occurs after spin-casting the active layer onto the PFN layer, when residual solvent molecules act as a plasticizer. The DIO additive, with a higher boiling point than the host solvent, has a longer residence time in the spin-cast active layer, resulting in more PC71BM smearing and therefore more efficient electron transport. This work provides important insight and guidance to further enhancement of i-OSC performance by materials and interface engineering.

  13. Plastic Schottky barrier solar cells

    DOE Patents [OSTI]

    Waldrop, James R.; Cohen, Marshall J.

    1984-01-24

    A photovoltaic cell structure is fabricated from an active medium including an undoped, intrinsically p-type organic semiconductor comprising polyacetylene. When a film of such material is in rectifying contact with a magnesium electrode, a Schottky-barrier junction is obtained within the body of the cell structure. Also, a gold overlayer passivates the magnesium layer on the undoped polyacetylene film.

  14. Understanding S-shaped current-voltage characteristics of organic solar cells: Direct measurement of potential distributions by scanning Kelvin probe

    SciTech Connect (OSTI)

    Saive, Rebecca Kowalsky, Wolfgang; Institut für Hochfrequenztechnik, TU Braunschweig, 38106 Braunschweig; Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg ; Mueller, Christian; Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg ; Schinke, Janusz; Lovrincic, Robert; Institut für Hochfrequenztechnik, TU Braunschweig, 38106 Braunschweig

    2013-12-09

    We present a comparison of the potential distribution along the cross section of bilayer poly(3-hexylthiophene)/1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C61 (P3HT/PCBM) solar cells, which show normal and anomalous, S-shaped current-voltage (IV) characteristics. We expose the cross sections of the devices with a focussed ion beam and measure them with scanning Kelvin probe microscopy. We find that in the case of S-shaped IV-characteristics, there is a huge potential drop at the PCBM/Al top contact, which does not occur in solar cells with normal IV-characteristics. This behavior confirms the assumption that S-shaped curves are caused by hindered charge transport at interfaces.

  15. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dry Flexible, lightweight, and inexpensive, plastic solar cells (known as organic photovoltaics, or "OPVs" for short) can conceivably be used in all manner of ways, from...

  16. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print Wednesday, 27 March 2013 00:00 The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the

  17. Nontoxic quantum dot research improves solar cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nontoxic quantum dot research improves solar cells Nontoxic quantum dot research improves solar cells Solar cells made with low-cost, nontoxic copper-based quantum dots can achieve unprecedented longevity and efficiency, according to a study by LANL and Sharp Corporation. December 10, 2013 Hunter McDaniel, Los Alamos National Laboratory postdoctoral researcher, works in the laboratory developing next-generation quantum dots that could revolutionize photovoltaic technology. Hunter McDaniel, Los

  18. Solar Cell Modules With Improved Backskin

    DOE Patents [OSTI]

    Gonsiorawski, Ronald C. (Danvers, MA)

    2003-12-09

    A laminated solar cell module comprises a front light transmitting support, a plurality of interconnected solar cells encapsulated by a light-transmitting encapsulant material, and an improved backskin formed of an ionomer/nylon alloy. The improved backskin has a toughness and melting point temperature sufficiently great to avoid any likelihood of it being pierced by any of the components that interconnect the solar cells.

  19. Bypass diode for a solar cell

    DOE Patents [OSTI]

    Rim, Seung Bum (Palo Alto, CA); Kim, Taeseok (San Jose, CA); Smith, David D. (Campbell, CA); Cousins, Peter J. (Menlo Park, CA)

    2012-03-13

    Bypass diodes for solar cells are described. In one embodiment, a bypass diode for a solar cell includes a substrate of the solar cell. A first conductive region is disposed above the substrate, the first conductive region of a first conductivity type. A second conductive region is disposed on the first conductive region, the second conductive region of a second conductivity type opposite the first conductivity type.

  20. TOPCAT Solar Cell Alignment & Energy Concentration Technology...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Return to Search TOPCAT Solar Cell Alignment & Energy Concentration ... It is a variation of current methods used on ... Applications and Industries Clean energy production ...

  1. The Silicon Solar Cell Turns 50

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Daryl Chapin, Calvin Fuller, and Gerald Pearson likely never imagined inventing a solar cell that would revolutionize the photovoltaics industry. There wasn't even a photovoltaics...

  2. Pennsylvania Company Develops Solar Cell Printing Technology

    Broader source: Energy.gov [DOE]

    The technology uses Plextronics’ conductive inks that can be printed by manufacturers worldwide to make solar cells, potentially as easily as they might print a newspaper.

  3. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John

    2014-11-04

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  4. Front contact solar cell with formed emitter

    DOE Patents [OSTI]

    Cousins, Peter John (Menlo Park, CA)

    2012-07-17

    A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

  5. Method for processing silicon solar cells

    DOE Patents [OSTI]

    Tsuo, Y. Simon (Golden, CO); Landry, Marc D. (Lafayette, CO); Pitts, John R. (Lakewood, CO)

    1997-01-01

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystallline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation.

  6. Method for processing silicon solar cells

    DOE Patents [OSTI]

    Tsuo, Y.S.; Landry, M.D.; Pitts, J.R.

    1997-05-06

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystalline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation. 2 figs.

  7. Shiny quantum dots brighten future of solar cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Shiny quantum dots brighten future of solar cells Shiny quantum dots brighten future of solar ... dots can be applied in solar energy by helping more efficiently harvest sunlight. ...

  8. Current and lattice matched tandem solar cell

    DOE Patents [OSTI]

    Olson, Jerry M. (Lakewood, CO)

    1987-01-01

    A multijunction (cascade) tandem photovoltaic solar cell device is fabricated of a Ga.sub.x In.sub.1-x P (0.505.ltoreq.X.ltoreq.0.515) top cell semiconductor lattice matched to a GaAs bottom cell semiconductor at a low-resistance heterojunction, preferably a p+/n+ heterojunction between the cells. The top and bottom cells are both lattice matched and current matched for high efficiency solar radiation conversion to electrical energy.

  9. Fullerene surfactants and their use in polymer solar cells

    SciTech Connect (OSTI)

    Jen, Kwan-Yue; Yip, Hin-Lap; Li, Chang-Zhi

    2015-12-15

    Fullerene surfactant compounds useful as interfacial layer in polymer solar cells to enhance solar cell efficiency. Polymer solar cell including a fullerene surfactant-containing interfacial layer intermediate cathode and active layer.

  10. p-Type semiconducting nickel oxide as an efficiency-enhancing anodal interfacial layer in bulk heterojunction solar cells

    DOE Patents [OSTI]

    Irwin, Michael D; Buchholz, Donald B; Marks, Tobin J; Chang, Robert P. H.

    2014-11-25

    The present invention, in one aspect, relates to a solar cell. In one embodiment, the solar cell includes an anode, a p-type semiconductor layer formed on the anode, and an active organic layer formed on the p-type semiconductor layer, where the active organic layer has an electron-donating organic material and an electron-accepting organic material.

  11. PROJECT PROFILE: Stable Perovskite Solar Cells via Chemical Vapor...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Stable Perovskite Solar Cells via Chemical Vapor Deposition PROJECT PROFILE: Stable Perovskite Solar Cells via Chemical Vapor Deposition Funding Opportunity: SuNLaMP SunShot ...

  12. Un-Nanostructuring Solar Cells | ANSER Center | Argonne-Northwestern

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Laboratory Un-Nanostructuring Solar Cells Home > Research > ANSER Research Highlights > Un-Nanostructuring Solar Cells

  13. Nanocrystal solar cells processed from solution (Patent) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Nanocrystal solar cells processed from solution Citation Details In-Document Search Title: Nanocrystal solar cells processed from solution A photovoltaic device having a first...

  14. Solland Solar Cells BV Shanghai | Open Energy Information

    Open Energy Info (EERE)

    Cells BV Shanghai Jump to: navigation, search Name: Solland Solar Cells BV (Shanghai) Place: Shanghai, Shanghai Municipality, China Zip: 200030 Sector: Solar Product:...

  15. Technique Reveals Critical Physics in Deep Regions of Solar Cells...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    minority-carrier lifetime deep within photovoltaic samples to help develop more efficient solar cells. When developing a solar photovoltaic (PV) cell, designers benefit from having...

  16. Hybrid Solar Cells via UV Polymerization of Polymer Precursor...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Cells via UV Polymerization of Polymer Precursor Technology available for licensing: A method to create improved hybrid solar cells through the ultraviolet (UV)...

  17. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy

  18. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy

  19. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy

  20. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy

  1. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy

  2. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy

  3. The Importance of Domain Size and Purity in High-Efficiency Organic Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy

  4. Heterojunction solar cell with passivated emitter surface

    DOE Patents [OSTI]

    Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO)

    1994-01-01

    A high-efficiency heterojunction solar cell wherein a thin emitter layer (preferably Ga.sub.0.52 In.sub.0.48 P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer.

  5. Solar cell with silicon oxynitride dielectric layer

    DOE Patents [OSTI]

    Shepherd, Michael; Smith, David D

    2015-04-28

    Solar cells with silicon oxynitride dielectric layers and methods of forming silicon oxynitride dielectric layers for solar cell fabrication are described. For example, an emitter region of a solar cell includes a portion of a substrate having a back surface opposite a light receiving surface. A silicon oxynitride (SiO.sub.xN.sub.y, 0

  6. Bypass diode for a solar cell

    DOE Patents [OSTI]

    Rim, Seung Bum; Kim, Taeseok; Smith, David D; Cousins, Peter J

    2013-11-12

    Methods of fabricating bypass diodes for solar cells are described. In once embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed on the first conductive region. In another embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed within, and surrounded by, an uppermost portion of the first conductive region but is not formed in a lowermost portion of the first conductive region.

  7. Heterojunction solar cell with passivated emitter surface

    DOE Patents [OSTI]

    Olson, J.M.; Kurtz, S.R.

    1994-05-31

    A high-efficiency heterojunction solar cell is described wherein a thin emitter layer (preferably Ga[sub 0.52]In[sub 0.48]P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer. 1 fig.

  8. NREL: Photovoltaics Research - Potential of Perovskite Solar Cells Featured

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in Solar Today Potential of Perovskite Solar Cells Featured in Solar Today February 11, 2016 Familiar with perovskite solar cells? If not, you'll probably hear more about them soon. Perovskites are a family of materials receiving considerable attention by solar cell researchers due to the rapid rise of solar conversion efficiencies, increasing from about 4% to almost 22% in just six years. In an interview published in Solar Today (winter 2015 edition), Dr. Jao van de Lagemaat, director of

  9. Cascade solar cell having conductive interconnects

    DOE Patents [OSTI]

    Borden, Peter G. (Menlo Park, CA); Saxena, Ram R. (Saratoga, CA)

    1982-10-26

    Direct ohmic contact between the cells in an epitaxially grown cascade solar cell is obtained by means of conductive interconnects formed through grooves etched intermittently in the upper cell. The base of the upper cell is directly connected by the conductive interconnects to the emitter of the bottom cell. The conductive interconnects preferably terminate on a ledge formed in the base of the upper cell.

  10. Indium oxide/n-silicon heterojunction solar cells

    DOE Patents [OSTI]

    Feng, Tom (Morris Plains, NJ); Ghosh, Amal K. (New Providence, NJ)

    1982-12-28

    A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

  11. LQ Energy LDK Solar Q Cells JV | Open Energy Information

    Open Energy Info (EERE)

    LQ Energy LDK Solar Q Cells JV Jump to: navigation, search Name: LQ Energy (LDK Solar & Q-Cells JV) Place: Saxony-Anhalt, Germany Sector: Solar Product: Germany-based JV between...

  12. Dye-sensitized solar cells

    DOE Patents [OSTI]

    Skotheim, Terje A. [Berkeley, CA

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

  13. Dye-sensitized solar cells

    DOE Patents [OSTI]

    Skotheim, T.A.

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

  14. Nontoxic quantum dot research improves solar cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    reported for any quantum dot solar cell," said Hunter McDaniel. Record power-conversion efficiency at Los Alamos from quantum-dot sensitized photovoltaics LOS ALAMOS, N.M., Dec....

  15. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    must be identified and fixed before they can be incorporated for use in mass-produced solar cells. This research represents a first step towards establishing a feedback loop to...

  16. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal devices, but...

  17. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    which can be controlled by adjusting the orbital energies. Relevant energy levels of a molecular solar cell. A photon from sunlight (green arrow) generates an electron-hole pair...

  18. Solar Photovoltaic Cell/Module Shipments Report

    Reports and Publications (EIA)

    2016-01-01

    Detailed data on manufacturing, imports, and exports of solar photovoltaic cell modules in the United States and its territories. Summary data include volumes in peak kilowatts and average prices.

  19. Enabling Thin Silicon Solar Cell Technology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    joined what he calls "the race of the SPV panel." He hopes to help create an SVP panel (a connected assembly of solar cells that turns sunlight into usable energy) that...

  20. High-efficiency solar cell and method for fabrication

    DOE Patents [OSTI]

    Hou, H.Q.; Reinhardt, K.C.

    1999-08-31

    A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD). 4 figs.

  1. High-efficiency solar cell and method for fabrication

    DOE Patents [OSTI]

    Hou, Hong Q.; Reinhardt, Kitt C.

    1999-01-01

    A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD).

  2. Processing Iron Pyrite Nanocrystals for Use in Solar Cells - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation Portal Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Processing Iron Pyrite Nanocrystals for Use in Solar Cells Lawrence Berkeley National Laboratory Contact LBL About This Technology Technology Marketing SummaryFor solar energy to become an economically viable energy source, alternative semiconductor materials to be used in solar cells must be found. Silicon, the longtime standard for solar cells, is expensive to process and in ever-growing demand.

  3. New Solar Cells to Boost Satellite Power

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Cells to Boost Satellite Power For more information contact: George Douglas (303) 275-4096 e:mail: george_douglas@nrel.gov TECSTAR SIGNS PATENT AGREEMENT WITH NREL Golden, Colo., May 7, 1998 — New solar cells that provide as much as 50 percent more power for satellites are orbiting Earth, helping flash back telephone and television signals. These cells are based on the two-junction, gallium indium phosphide on gallium arsenide designs developed at the U.S. Department of Energy's National

  4. Method of restoring degraded solar cells

    DOE Patents [OSTI]

    Staebler, David L. (Lawrenceville, NJ)

    1983-01-01

    Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200.degree. C. for at least 30 minutes restores their efficiency.

  5. Liquid cooled, linear focus solar cell receiver

    DOE Patents [OSTI]

    Kirpich, Aaron S. (Broomall, PA)

    1985-01-01

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  6. Liquid cooled, linear focus solar cell receiver

    DOE Patents [OSTI]

    Kirpich, A.S.

    1983-12-08

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  7. Method of restoring degraded solar cells

    DOE Patents [OSTI]

    Staebler, D.L.

    1983-02-01

    Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200 C for at least 30 minutes restores their efficiency. 2 figs.

  8. NREL Scientists Report First Solar Cell Producing More Electrons In

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Photocurrent Than Solar Photons Entering Cell - News Releases | NREL Scientists Report First Solar Cell Producing More Electrons In Photocurrent Than Solar Photons Entering Cell December 15, 2011 Researchers from the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have reported the first solar cell that produces a photocurrent that has an external quantum efficiency greater than 100 percent when photoexcited with photons from the high energy region of the solar

  9. NREL and Partners to Compare High-Efficiency Solar Cells from Three Nations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at Sites in Colorado and Yokohama, Japan - News Releases | NREL and Partners to Compare High-Efficiency Solar Cells from Three Nations at Sites in Colorado and Yokohama, Japan April 4, 2011 Golden, Colo., April 4, 2011 - The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is partnering with major international industrial technology and solar research organizations to test how solar cells from three manufacturers perform in two geographic locations with different

  10. Method of fabricating a solar cell array

    DOE Patents [OSTI]

    Lazzery, Angelo G. (Oaklyn, NJ); Crouthamel, Marvin S. (Pennsauken, NJ); Coyle, Peter J. (Oaklyn, NJ)

    1982-01-01

    A first set of pre-tabbed solar cells are assembled in a predetermined array with at least part of each tab facing upward, each tab being fixed to a bonding pad on one cell and abutting a bonding pad on an adjacent cell. The cells are held in place with a first vacuum support. The array is then inverted onto a second vacuum support which holds the tabs firmly against the cell pads they abut. The cells are exposed to radiation to melt and reflow the solder pads for bonding the tab portions not already fixed to bonding pads to these pads.

  11. The Kanatzidis - Chang Cell: dye sensitized all solid state solar...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The Kanatzidis - Chang Cell: dye sensitized all solid state solar cell Home > Research > ANSER Research Highlights > The Kanatzidis - Chang Cell: dye sensitized all solid state...

  12. Fabricating solar cells with silicon nanoparticles

    DOE Patents [OSTI]

    Loscutoff, Paul; Molesa, Steve; Kim, Taeseok

    2014-09-02

    A laser contact process is employed to form contact holes to emitters of a solar cell. Doped silicon nanoparticles are formed over a substrate of the solar cell. The surface of individual or clusters of silicon nanoparticles is coated with a nanoparticle passivation film. Contact holes to emitters of the solar cell are formed by impinging a laser beam on the passivated silicon nanoparticles. For example, the laser contact process may be a laser ablation process. In that case, the emitters may be formed by diffusing dopants from the silicon nanoparticles prior to forming the contact holes to the emitters. As another example, the laser contact process may be a laser melting process whereby portions of the silicon nanoparticles are melted to form the emitters and contact holes to the emitters.

  13. Solar cell contact formation using laser ablation

    DOE Patents [OSTI]

    Harley, Gabriel; Smith, David D.; Cousins, Peter John

    2014-07-22

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline materiat layer; and forming conductive contacts in the plurality of contact holes.

  14. High throughput solar cell ablation system

    DOE Patents [OSTI]

    Harley, Gabriel; Pass, Thomas; Cousins, Peter John; Viatella, John

    2014-10-14

    A solar cell is formed using a solar cell ablation system. The ablation system includes a single laser source and several laser scanners. The laser scanners include a master laser scanner, with the rest of the laser scanners being slaved to the master laser scanner. A laser beam from the laser source is split into several laser beams, with the laser beams being scanned onto corresponding wafers using the laser scanners in accordance with one or more patterns. The laser beams may be scanned on the wafers using the same or different power levels of the laser source.

  15. High throughput solar cell ablation system

    DOE Patents [OSTI]

    Harley, Gabriel; Pass, Thomas; Cousins, Peter John; Viatella, John

    2012-09-11

    A solar cell is formed using a solar cell ablation system. The ablation system includes a single laser source and several laser scanners. The laser scanners include a master laser scanner, with the rest of the laser scanners being slaved to the master laser scanner. A laser beam from the laser source is split into several laser beams, with the laser beams being scanned onto corresponding wafers using the laser scanners in accordance with one or more patterns. The laser beams may be scanned on the wafers using the same or different power levels of the laser source.

  16. Origami-enabled deformable silicon solar cells

    SciTech Connect (OSTI)

    Tang, Rui; Huang, Hai; Liang, Hanshuang; Liang, Mengbing; Tu, Hongen; Xu, Yong; Song, Zeming; Jiang, Hanqing; Yu, Hongyu

    2014-02-24

    Deformable electronics have found various applications and elastomeric materials have been widely used to reach flexibility and stretchability. In this Letter, we report an alternative approach to enable deformability through origami. In this approach, the deformability is achieved through folding and unfolding at the creases while the functional devices do not experience strain. We have demonstrated an example of origami-enabled silicon solar cells and showed that this solar cell can reach up to 644% areal compactness while maintaining reasonable good performance upon cyclic folding/unfolding. This approach opens an alternative direction of producing flexible, stretchable, and deformable electronics.

  17. Solar cell contact formation using laser ablation

    DOE Patents [OSTI]

    Harley, Gabriel; Smith, David D.; Cousins, Peter John

    2015-07-21

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline material layer; and forming conductive contacts in the plurality of contact holes.

  18. Solar cell contact formation using laser ablation

    DOE Patents [OSTI]

    Harley, Gabriel; Smith, David; Cousins, Peter

    2012-12-04

    The formation of solar cell contacts using a laser is described. A method of fabricating a back-contact solar cell includes forming a poly-crystalline material layer above a single-crystalline substrate. The method also includes forming a dielectric material stack above the poly-crystalline material layer. The method also includes forming, by laser ablation, a plurality of contacts holes in the dielectric material stack, each of the contact holes exposing a portion of the poly-crystalline material layer; and forming conductive contacts in the plurality of contact holes.

  19. Multi-junction solar cell device

    DOE Patents [OSTI]

    Friedman, Daniel J. (Lakewood, CO); Geisz, John F. (Wheat Ridge, CO)

    2007-12-18

    A multi-junction solar cell device (10) is provided. The multi-junction solar cell device (10) comprises either two or three active solar cells connected in series in a monolithic structure. The multi-junction device (10) comprises a bottom active cell (20) having a single-crystal silicon substrate base and an emitter layer (23). The multi-junction device (10) further comprises one or two subsequent active cells each having a base layer (32) and an emitter layer (23) with interconnecting tunnel junctions between each active cell. At least one layer that forms each of the top and middle active cells is composed of a single-crystal III-V semiconductor alloy that is substantially lattice-matched to the silicon substrate (22). The polarity of the active p-n junction cells is either p-on-n or n-on-p. The present invention further includes a method for substantially lattice matching single-crystal III-V semiconductor layers with the silicon substrate (22) by including boron and/or nitrogen in the chemical structure of these layers.

  20. Efficient Polymer Solar Cells - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Startup America Startup America Solar Thermal Solar Thermal Solar Photovoltaic Solar Photovoltaic Building Energy Efficiency Building Energy Efficiency Find More Like This Return...

  1. When Function Follows Form: Plastic Solar Cells | ANSER Center |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Argonne-Northwestern National Laboratory When Function Follows Form: Plastic Solar Cells Home > Research > ANSER Research Highlights > When Function Follows Form: Plastic Solar Cells

  2. Harmful Shunting Mechanisms Found in Silicon Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

    Scientists developed near-field optical microscopy for imaging electrical breakdown in solar cells and identified critical electrical breakdown mechanisms operating in industrial silicon and epitaxial silicon solar cells.

  3. Ohmic contacts for solar cells by arc plasma spraying

    DOE Patents [OSTI]

    Narasimhan, Mandayam C. (Seekonk, MA); Roessler, Barton (Barrington, RI); Loferski, Joseph J. (Providence, RI)

    1982-01-01

    The method of applying ohmic contacts to a semiconductor, such as a silicon body or wafer used in solar cells, by the use of arc plasma spraying, and solar cells resulting therefrom.

  4. Konca Solar Cell Wuxi Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Konca Solar Cell Wuxi Co Ltd Jump to: navigation, search Name: Konca Solar Cell (Wuxi) Co Ltd Place: Wuxi, Jiangsu Province, China Product: China-based PV wafer manufacturer....

  5. Award-Winning Etching Process Cuts Solar Cell Costs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Award-Winning Etching Process Cuts Solar Cell Costs Optimizing solar-cell technology can be a complex job, requiring expertise in material science, physics, and optics to convert...

  6. Metal electrode for amorphous silicon solar cells

    DOE Patents [OSTI]

    Williams, Richard (Princeton, NJ)

    1983-01-01

    An amorphous silicon solar cell having an N-type region wherein the contact to the N-type region is composed of a material having a work function of about 3.7 electron volts or less. Suitable materials include strontium, barium and magnesium and rare earth metals such as gadolinium and yttrium.

  7. Method of fabricating a solar cell

    DOE Patents [OSTI]

    Pass, Thomas; Rogers, Robert

    2014-02-25

    Methods of fabricating solar cells are described. A porous layer may be formed on a surface of a substrate, the porous layer including a plurality of particles and a plurality of voids. A solution may be dispensed into one or more regions of the porous layer to provide a patterned composite layer. The substrate may then be heated.

  8. Enhanced Photon Recycling in Multijunction Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Cells Work w as p erformed a t U IUC a nd B erkeley X. Sheng, M.H. Yun, C. Zhang, A.M. Al---Okaily, M. Masouraki, L. Shen, S. Wang, W.L. Wilson, J.Y. Kim, P....

  9. Tandem junction amorphous silicon solar cells

    DOE Patents [OSTI]

    Hanak, Joseph J. (Lawrenceville, NJ)

    1981-01-01

    An amorphous silicon solar cell has an active body with two or a series of layers of hydrogenated amorphous silicon arranged in a tandem stacked configuration with one optical path and electrically interconnected by a tunnel junction. The layers of hydrogenated amorphous silicon arranged in tandem configuration can have the same bandgap or differing bandgaps.

  10. Organic Photovoltaic Cells with an Electric Field Integrally-Formed at the

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Heterojunction Interface - Energy Innovation Portal Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Organic Photovoltaic Cells with an Electric Field Integrally-Formed at the Heterojunction Interface National Renewable Energy Laboratory Brookhaven National Laboratory Contact NREL About This Technology Figure 4 Figure 4 Figure 6 Figure 6 Technology Marketing SummaryStandard solar cells made from inorganic semiconductors, such as silicon cells, have dominated the

  11. Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power ... Hydrogen Infrastructure Hydrogen Production Market Transformation Fuel Cells ...

  12. Nanocluster production for solar cell applications

    SciTech Connect (OSTI)

    Al Dosari, Haila M.; Ayesh, Ahmad I.

    2013-08-07

    This research focuses on the fabrication and characterization of silver (Ag) and silicon (Si) nanoclusters that might be used for solar cell applications. Silver and silicon nanoclusters have been synthesized by means of dc magnetron sputtering and inert gas condensation inside an ultra-high vacuum compatible system. We have found that nanocluster size distributions can be tuned by various source parameters, such as the sputtering discharge power, flow rate of argon inert gas, and aggregation length. Quadrupole mass filter and transmission electron microscopy were used to evaluate the size distribution of Ag and Si nanoclusters. Ag nanoclusters with average size in the range of 3.6–8.3 nm were synthesized (herein size refers to the nanocluster diameter), whereas Si nanoclusters' average size was controlled to range between 2.9 and 7.4 nm by controlling the source parameters. This work illustrates the ability of controlling the Si and Ag nanoclusters' sizes by proper optimization of the operation conditions. By controlling nanoclusters' sizes, one can alter their surface properties to suit the need to enhance solar cell efficiency. Herein, Ag nanoclusters were deposited on commercial polycrystalline solar cells. Short circuit current (I{sub SC}), open circuit voltage (V{sub OC}), fill factor, and efficiency (?) were obtained under light source with an intensity of 30 mW/cm{sup 2}. A 22.7% enhancement in solar cell efficiency could be measured after deposition of Ag nanoclusters, which demonstrates that Ag nanoclusters generated in this work are useful to enhance solar cell efficiency.

  13. Flexible thermal cycle test equipment for concentrator solar cells

    DOE Patents [OSTI]

    Hebert, Peter H.; Brandt, Randolph J.

    2012-06-19

    A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

  14. Diffraction: Enhanced Light Absorption of Solar Cells and Photodetectors -

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Innovation Portal Solar Thermal Solar Thermal Solar Photovoltaic Solar Photovoltaic Advanced Materials Advanced Materials Find More Like This Return to Search Diffraction: Enhanced Light Absorption of Solar Cells and Photodetectors Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (890 KB) Technology Marketing SummaryThe solar and photovoltaic industry has grown steadily over the last several years. In order to maintain

  15. The Kanatzidis - Chang Cell: dye sensitized all solid state solar cell |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ANSER Center | Argonne-Northwestern National Laboratory The Kanatzidis - Chang Cell: dye sensitized all solid state solar cell Home > Research > ANSER Research Highlights > The Kanatzidis - Chang Cell: dye sensitized all solid state solar cell

  16. Method of fabricating a solar cell with a tunnel dielectric layer

    SciTech Connect (OSTI)

    Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David D.; Waldhauer, Ann

    2015-08-18

    Method of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

  17. Method of fabricating a solar cell with a tunnel dielectric layer

    DOE Patents [OSTI]

    Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David; Waldhauer, Ann

    2012-12-18

    Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

  18. Method of fabricating a solar cell with a tunnel dielectric layer

    DOE Patents [OSTI]

    Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David D; Waldhauer, Ann

    2014-04-29

    Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

  19. Low Cost, High Efficiency Tandem Silicon Solar Cells and LEDs...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    higher than those of simple multi or single crystalline silicon cells. While three junction non-silicon tandem solar cells have achieved unconcentrated efficiencies of up to...

  20. 2D Monolayers Could Yield Thinnest Solar Cells Ever

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Thinnest solar cells ever 2D Monolayers Could Yield Thinnest Solar Cells Ever October 21, 2013 Contact: Kathy Kincade, +1 510 495 2124, kkincade@lbl.gov Efforts to improve solar cells have historically focused on improving energy conversion efficiencies and lowering manufacturing costs. But new computer simulations have shown how using a different type of material could yield thinner, more lightweight solar panels that provide power densities - watts per kilogram of material - orders of

  1. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    cell. The class of dye molecules used in this research is related to the dye that gives blue jeans their color. By choosing organic molecules, an enormous repertoire of possible...

  2. Compensated amorphous-silicon solar cell

    DOE Patents [OSTI]

    Devaud, G.

    1982-06-21

    An amorphous silicon solar cell including an electrically conductive substrate, a layer of glow discharge deposited hydrogenated amorphous silicon having regions of differing conductivity with at least one region of intrinsic hydrogenated amorphous silicon. The layer of hydrogenated amorphous silicon has opposed first and second major surfaces where the first major surface contacts the elecrically conductive substrate and an electrode for electrically contacting the second major surface. The intrinsic hydrogenated amorphous silicon region is deposited in a glow discharge with an atmosphere which includes not less than about 0.02 atom percent mono-atomic boron. An improved N.I.P. solar cell is disclosed using a BF/sub 3/ doped intrinsic layer.

  3. TFB:TPDSi2 interfacial layer usable in organic photovoltaic cells

    DOE Patents [OSTI]

    Marks, Iobin J. (Evanston, IL); Hains, Alexander W. (Evanston, IL)

    2011-02-15

    The present invention, in one aspect, relates to a solar cell. In one embodiment, the solar cell includes an anode; an active organic layer comprising an electron-donating organic material and an electron-accepting organic material; and an interfacial layer formed between the anode and active organic layer, where the interfacial layer comprises a hole-transporting polymer characterized with a hole-mobility higher than that of the electron-donating organic material in the active organic layer, and a small molecule that has a high hole-mobility and is capable of crosslinking on contact with air.

  4. Ultra-Fast Quantum Efficiency Solar Cell Test - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    more efficient in converting solar energy into electricity. ... QE binning will not do away with binning based on current-vo... All of the LEDs in the array illuminate a solar cell with ...

  5. Voltage-matched multijunction solar cell architectures for integrating...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Return to Search Voltage-matched multijunction solar cell architectures for integrating PV ... to reduce the total installed cost of solar energy systems to .06 per kilowatt-hour ...

  6. Defect behavior of polycrystalline solar cell silicon

    SciTech Connect (OSTI)

    Schroder, D.K.; Park, S.H.; Hwang, I.G.; Mohr, J.B.; Hanly, M.P.

    1993-05-01

    The major objective of this study, conducted from October 1988 to September 1991, was to gain an understanding of the behavior of impurities in polycrystalline silicon and the influence of these impurities on solar cell efficiency. The authors studied edge-defined film-fed growth (EFG) and cast poly-Si materials and solar cells. With EFG Si they concentrated on chromium-doped materials and cells to determine the role of Cr on solar cell performance. Cast poly-Si samples were not deliberately contaminated. Samples were characterized by cell efficiency, current-voltage, deep-level transient spectroscopy (DLTS), surface photovoltage (SPV), open-circuit voltage decay, secondary ion mass spectrometry, and Fourier transform infrared spectroscopy measurements. They find that Cr forms Cr-B pairs with boron at room temperature and these pairs dissociate into Cr{sub i}{sup +} and B{sup {minus}} during anneals at 210{degrees}C for 10 min. Following the anneal, Cr-B pairs reform at room temperature with a time constant of 230 h. Chromium forms CrSi{sub 2} precipitates in heavily contaminated regions and they find evidence of CrSi{sub 2} gettering, but a lack of chromium segregation or precipitation to grain boundaries and dislocations. Cr-B pairs have well defined DLTS peaks. However, DLTS spectra of other defects are not well defined, giving broad peaks indicative of defects with a range of energy levels in the band gap. In some high-stress, low-efficiency cast poly-Si they detect SiC precipitates, but not in low-stress, high-efficiency samples. SPV measurements result in nonlinear SPV curves in some materials that are likely due to varying optical absorption coefficients due to locally varying stress in the material.

  7. Synthesis of CdSe quantum dots for quantum dot sensitized solar cell

    SciTech Connect (OSTI)

    Singh, Neetu Kapoor, Avinashi; Kumar, Vinod; Mehra, R. M.

    2014-04-24

    CdSe Quantum Dots (QDs) of size 0.85 nm were synthesized using chemical route. ZnO based Quantum Dot Sensitized Solar Cell (QDSSC) was fabricated using CdSe QDs as sensitizer. The Pre-synthesized QDs were found to be successfully adsorbed on front ZnO electrode and had potential to replace organic dyes in Dye Sensitized Solar Cells (DSSCs). The efficiency of QDSSC was obtained to be 2.06 % at AM 1.5.

  8. High Efficiency Multiple-Junction Solar Cells - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search High Efficiency Multiple-Junction Solar Cells Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (937 KB) Technology Marketing SummarySingle junction solar cells have limited efficiency and fail to extract maximum energy from photons outside of a specific spectral region. Higher efficiency and optical to electrical energy conversion is achieved by stacking

  9. TRANSPARENT COATINGS FOR SOLAR CELLS RESEARCH

    SciTech Connect (OSTI)

    Glatkowski, P.J.; Landis, D.A.

    2013-04-16

    Todays solar cells are fabricated using metal oxide based transparent conductive coatings (TCC) or metal wires with optoelectronic performance exceeding that currently possible with Carbon Nanotube (CNT) based TCCs. The motivation for replacing current TCC is their inherent brittleness, high deposition cost, and high deposition temperatures; leading to reduced performance on thin substrates. With improved processing, application and characterization techniques Nanofiber and/or CNT based TCCs can overcome these shortcomings while offering the ability to be applied in atmospheric conditions using low cost coating processes At todays level of development, CNT based TCC are nearing commercial use in touch screens, some types of information displays (i.e. electronic paper), and certain military applications. However, the resistivity and transparency requirements for use in current commercial solar cells are more stringent than in many of these applications. Therefore, significant research on fundamental nanotube composition, dispersion and deposition are required to reach the required performance commanded by photovoltaic devices. The objective of this project was to research and develop transparent conductive coatings based on novel nanomaterial composite coatings, which comprise nanotubes, nanofibers, and other nanostructured materials along with binder materials. One objective was to show that these new nanomaterials perform at an electrical resistivity and optical transparency suitable for use in solar cells and other energy-related applications. A second objective was to generate new structures and chemistries with improved resistivity and transparency performance. The materials also included the binders and surface treatments that facilitate the utility of the electrically conductive portion of these composites in solar photovoltaic devices. Performance enhancement venues included: CNT purification and metallic tube separation techniques, chemical doping, CNT patterning and alignment, advances in commercial and research materials and field effect schemes. In addition, Eikos continued to develop improved efficiency coating materials and transfer methods suitable for batch and continuous roll-to-roll fabrication requirements. Finally, Eikos collaborated with NREL and the PV-community at large in fabricating and characterizing InvisiconĂ?Â?Ă?Âź enabled solar cells.

  10. Molecular helices as electron acceptors in high-performance bulk heterojunction solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu M. Zhong; Nam, Chang -Yong; Trinh, M. Tuan; Chen, Rongsheng; Purdum, Geoffrey E.; Khlyabich, Petr P.; Sezen, Melda; Oh, Seokjoon; Zhu, Haiming; Fowler, Brandon; et al

    2015-09-18

    Despite numerous organic semiconducting materials synthesized for organic photovoltaics in the past decade, fullerenes are widely used as electron acceptors in highly efficient bulk-heterojunction solar cells. None of the non-fullerene bulk heterojunction solar cells have achieved efficiencies as high as fullerene-based solar cells. Design principles for fullerene-free acceptors remain unclear in the field. Here we report examples of helical molecular semiconductors as electron acceptors that are on par with fullerene derivatives in efficient solar cells. We achieved an 8.3% power conversion efficiency in a solar cell, which is a record high for non-fullerene bulk heterojunctions. Femtosecond transient absorption spectroscopy revealedmore » both electron and hole transfer processes at the donor–acceptor interfaces. Atomic force microscopy reveals a mesh-like network of acceptors with pores that are tens of nanometres in diameter for efficient exciton separation and charge transport. As a result, this study describes a new motif for designing highly efficient acceptors for organic solar cells.« less

  11. Molecular helices as electron acceptors in high-performance bulk heterojunction solar cells

    SciTech Connect (OSTI)

    Yu M. Zhong; Nam, Chang -Yong; Trinh, M. Tuan; Chen, Rongsheng; Purdum, Geoffrey E.; Khlyabich, Petr P.; Sezen, Melda; Oh, Seokjoon; Zhu, Haiming; Fowler, Brandon; Zhang, Boyuan; Wang, Wei; Sfeir, Matthew Y.; Black, Charles T.; Steigerwald, Michael L.; Loo, Yueh -Lin; Ng, Fay; Zhu, X. -Y.; Nuckolls, Colin

    2015-09-18

    Despite numerous organic semiconducting materials synthesized for organic photovoltaics in the past decade, fullerenes are widely used as electron acceptors in highly efficient bulk-heterojunction solar cells. None of the non-fullerene bulk heterojunction solar cells have achieved efficiencies as high as fullerene-based solar cells. Design principles for fullerene-free acceptors remain unclear in the field. Here we report examples of helical molecular semiconductors as electron acceptors that are on par with fullerene derivatives in efficient solar cells. We achieved an 8.3% power conversion efficiency in a solar cell, which is a record high for non-fullerene bulk heterojunctions. Femtosecond transient absorption spectroscopy revealed both electron and hole transfer processes at the donor–acceptor interfaces. Atomic force microscopy reveals a mesh-like network of acceptors with pores that are tens of nanometres in diameter for efficient exciton separation and charge transport. As a result, this study describes a new motif for designing highly efficient acceptors for organic solar cells.

  12. Solar module having reflector between cells

    DOE Patents [OSTI]

    Kardauskas, Michael J. (Billerica, MA)

    1999-01-01

    A photovoltaic module comprising an array of electrically interconnected photovoltaic cells disposed in a planar and mutually spaced relationship between a light-transparent front cover member in sheet form and a back sheet structure is provided with a novel light-reflecting means disposed between adjacent cells for reflecting light falling in the areas between cells back toward said transparent cover member for further internal reflection onto the solar cells. The light-reflecting comprises a flexible plastic film that has been embossed so as to have a plurality of small V-shaped grooves in its front surface, and a thin light-reflecting coating on said front surface, the portions of said coating along the sides of said grooves forming light-reflecting facets, said grooves being formed so that said facets will reflect light impinging thereon back into said transparent cover sheet with an angle of incidence greater than the critical angle, whereby substantially all of the reflected light will be internally reflected from said cover sheet back to said solar modules, thereby increasing the current output of the module.

  13. High efficiency, radiation-hard solar cells

    SciTech Connect (OSTI)

    Ager III, J.W.; Walukiewicz, W.

    2004-10-22

    The direct gap of the In{sub 1-x}Ga{sub x}N alloy system extends continuously from InN (0.7 eV, in the near IR) to GaN (3.4 eV, in the mid-ultraviolet). This opens the intriguing possibility of using this single ternary alloy system in single or multi-junction (MJ) solar cells of the type used for space-based surveillance satellites. To evaluate the suitability of In{sub 1-x}Ga{sub x}N as a material for space applications, high quality thin films were grown with molecular beam epitaxy and extensive damage testing with electron, proton, and alpha particle radiation was performed. Using the room temperature photoluminescence intensity as a indirect measure of minority carrier lifetime, it is shown that In{sub 1-x}Ga{sub x}N retains its optoelectronic properties at radiation damage doses at least 2 orders of magnitude higher than the damage thresholds of the materials (GaAs and GaInP) currently used in high efficiency MJ cells. This indicates that the In{sub 1-x}Ga{sub x}N is well-suited for the future development of ultra radiation-hard optoelectronics. Critical issues affecting development of solar cells using this material system were addressed. The presence of an electron-rich surface layer in InN and In{sub 1-x}Ga{sub x}N (0 < x < 0.63) was investigated; it was shown that this is a less significant effect at large x. Evidence of p-type activity below the surface in Mg-doped InN was obtained; this is a significant step toward achieving photovoltaic action and, ultimately, a solar cell using this material.

  14. 'Nano'tubes, Surface Area & NanoSolar Cells

    K-12 Energy Lesson Plans and Activities Web site (EERE)

    This unit takes students through several introductory lessons designed to gain a better understanding of the 'nano' scale as it relates to the creation of a (dye-sensitized) solar cell (DSSC). The introductory lessons guide students through activities covering volume, surface area and density and exploration of the relationship between these factors. The unit culminates with students building a Gratzel cell, a solar cell employing a layer of nanospheres of TiO2 as the semiconductor and blackberry juice as the light absorber in a non-Si-based solar cell. Students are able to build a small solar cell and test its efficiency.

  15. Economical Pyrite-Based Solar Cells - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The first generation of solar cells, used in 90% of today's cells, have a focus of high efficiency. These cells use a single p-n junction to extract energy from photons, and are ...

  16. High efficiency solar cells combining a perovskite and a silicon heterojunction solar cells via an optical splitting system

    SciTech Connect (OSTI)

    Uzu, Hisashi E-mail: npark@skku.edu; Ichikawa, Mitsuru; Hino, Masashi; Nakano, Kunihiro; Meguro, Tomomi; Yamamoto, Kenji; Hernández, José Luis; Kim, Hui-Seon; Park, Nam-Gyu E-mail: npark@skku.edu

    2015-01-05

    We have applied an optical splitting system in order to achieve very high conversion efficiency for a full spectrum multi-junction solar cell. This system consists of multiple solar cells with different band gap optically coupled via an “optical splitter.” An optical splitter is a multi-layered beam splitter with very high reflection in the shorter-wave-length range and very high transmission in the longer-wave-length range. By splitting the incident solar spectrum and distributing it to each solar cell, the solar energy can be managed more efficiently. We have fabricated optical splitters and used them with a wide-gap amorphous silicon (a-Si) solar cell or a CH{sub 3}NH{sub 3}PbI{sub 3} perovskite solar cell as top cells, combined with mono-crystalline silicon heterojunction (HJ) solar cells as bottom cells. We have achieved with a 550?nm cutoff splitter an active area conversion efficiency of over 25% using a-Si and HJ solar cells and 28% using perovskite and HJ solar cells.

  17. TJ Solar Cell (GaInP/GaAs/Ge Ultrahigh-Efficiency Solar Cells

    SciTech Connect (OSTI)

    Friedman, Daniel

    2002-04-17

    This talk will discuss recent developments in III-V multijunction photovoltaic technology which have led to the highest-efficiency solar cells ever demonstrated. The relationship between the materials science of III-V semiconductors and the achievement of record solar cell efficiencies will be emphasized. For instance, epitaxially-grown GAInP has been found to form a spontaneously-ordered GaP/InP (111) superlattice. This ordering affects the band gap of the material, which in turn affects the design of solar cells which incorporate GaInP. For the next generation of ultrahigh-efficiency III-V solar cells, we need a new semiconductor which is lattice-matched to GaAs, has a band gap of 1 eV, and has long minority-carrier diffusion lengths. Out of a number of candidate materials, the recently-discovered alloy GaInNAs appears to have the greatest promise. This material satisfies the first two criteria, but has to date shown very low diffusion lengths, a problem which is our current focus in the development of these next-generation cells.

  18. Hybrid Solar Cells with Prescribed Nanoscale Morphologies Based onHyperbranched Semiconductor Nanocrystals

    SciTech Connect (OSTI)

    Gur, Ilan; Fromer, Neil A.; Chen, Chih-Ping; Kanaras, AntoniosG.; Alivisatos, A. Paul

    2006-09-09

    In recent years, the search to develop large-area solar cells at low cost has led to research on photovoltaic (PV) systems based on nanocomposites containing conjugated polymers. These composite films can be synthesized and processed at lower costs and with greater versatility than the solid state inorganic semiconductors that comprise today's solar cells. However, the best nanocomposite solar cells are based on a complex architecture, consisting of a fine blend of interpenetrating and percolating donor and acceptor materials. Cell performance is strongly dependent on blend morphology, and solution-based fabrication techniques often result in uncontrolled and irreproducible blends, whose composite morphologies are difficult to characterize accurately. Here we incorporate 3-dimensional hyper-branched colloidal semiconductor nanocrystals in solution-processed hybrid organic-inorganic solar cells, yielding reproducible and controlled nanoscale morphology.

  19. Solar Cell Nanotechnology Final Technical Report

    SciTech Connect (OSTI)

    Das, Biswajit

    2014-05-07

    The objective of this project is to develop a low cost nonlithographic nanofabrication technology for the fabrication of thin film porous templates as well as uniform arrays of semiconductor nanostructures for the implementation of high efficiency solar cells. Solar cells based on semiconductor nanostructures are expected to have very high energy conversion efficiencies due to the increased absorption coefficients of semiconductor nanostructures. In addition, the thin film porous template can be used for optimum surface texturing of solar cells leading to additional enhancement in energy conversion efficiency. An important requirement for these applications is the ability to synthesize nanostructure arrays of different dimensions with good size control. This project employed nanoporous alumina templates created by the anodization of aluminum thin films deposited on glass substrates for the fabrication of the nanostructures and optimized the process parameters to obtain uniform pore diameters. An additional requirement is uniformity or regularity of the nanostructure arrays. While constant current anodization was observed to provide controlled pore diameters, constant voltage anodization was needed for regularity of the nanostructure arrays. Thus a two-step anodization process was investigated and developed in this project for improving the pore size distribution and pore periodicity of the nanoporous alumina templates. CdTe was selected to be the active material for the nanowires, and the process for the successful synthesis of CdTe nanowires was developed in this project. Two different synthesis approaches were investigated in this project, electrochemical and electrophoretic deposition. While electrochemical synthesis was successfully employed for the synthesis of nanowires inside the pores of the alumina templates, the technique was determined to be non-optimum due to the need of elevated temperature that is detrimental to the structural integrity of the nanoporous alumina templates. In order to eliminate this problem, electrophoretic deposition was selected as the more appropriate technique, which involves the guided deposition of semiconductor nanoparticles in the presence of ultrasonic energy to form the crystalline nanowires. Extensive experimental research was carried out to optimize the process parameters for formation of crystalline nanowires. It was observed that the environmental bath temperature plays a critical role in determining the structural integrity of the nanowires and hence their lengths. Investigation was carried out for the formation of semitransparent ohmic contacts on the nanowires to facilitate photocurrent spectroscopy measurements as well as for solar cell implementation. Formation of such ohmic contacts was found to be challenging and a process involving mechanical and electrochemical polishing was developed to facilitate such contacts. The use of nanoporous alumina templates for the surface texturing of mono- and multi-crystalline solar cells was extensively investigated by electrochemical etching of the silicon through the pores of the nanoporous templates. The processes for template formation as well as etching were optimized and the alumina/silicon interface was investigated using capacitance-voltage characterization. The process developed was found to be viable for improving solar cell performance.

  20. Solare Cell Roof Tile And Method Of Forming Same

    DOE Patents [OSTI]

    Hanoka, Jack I. (Brookline, MA); Real, Markus (Oberberg, CH)

    1999-11-16

    A solar cell roof tile includes a front support layer, a transparent encapsulant layer, a plurality of interconnected solar cells and a backskin layer. The front support layer is formed of light transmitting material and has first and second surfaces. The transparent encapsulant layer is disposed adjacent the second surface of the front support layer. The interconnected solar cells has a first surface disposed adjacent the transparent encapsulant layer. The backskin layer has a first surface disposed adjacent a second surface of the interconnected solar cells, wherein a portion of the backskin layer wraps around and contacts the first surface of the front support layer to form the border region. A portion of the border region has an extended width. The solar cell roof tile may have stand-offs disposed on the extended width border region for providing vertical spacing with respect to an adjacent solar cell roof tile.

  1. Method of fabricating bifacial tandem solar cells

    DOE Patents [OSTI]

    Wojtczuk, Steven J; Chiu, Philip T; Zhang, Xuebing; Gagnon, Edward; Timmons, Michael

    2014-10-07

    A method of fabricating on a semiconductor substrate bifacial tandem solar cells with semiconductor subcells having a lower bandgap than the substrate bandgap on one side of the substrate and with subcells having a higher bandgap than the substrate on the other including, first, growing a lower bandgap subcell on one substrate side that uses only the same periodic table group V material in the dislocation-reducing grading layers and bottom subcells as is present in the substrate and after the initial growth is complete and then flipping the substrate and growing the higher bandgap subcells on the opposite substrate side which can be of different group V material.

  2. PROJECT PROFILE: Hybrid Perovskite Solar Cells | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hybrid Perovskite Solar Cells PROJECT PROFILE: Hybrid Perovskite Solar Cells Funding Opportunity: SuNLaMP SunShot Subprogram: Photovoltaics Location: National Renewable Energy Laboratory, Golden, CO Amount Awarded: $4,000,000 This project will demonstrate efficient, stabile, and scalable hybrid perovskite solar cells (HPSCs), rapidly transforming these new materials into an industry-relevant technology. The team will advance HPSC technology by improving the stability, efficiency, and scalability

  3. PROJECT PROFILE: Stable Perovskite Solar Cells via Chemical Vapor

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Deposition | Department of Energy Stable Perovskite Solar Cells via Chemical Vapor Deposition PROJECT PROFILE: Stable Perovskite Solar Cells via Chemical Vapor Deposition Funding Opportunity: SuNLaMP SunShot Subprogram: Photovoltaics Location: National Renewable Energy Laboratory, Golden, CO SunShot Award Amount: $125,000 This project is focused on novel approaches to remove risk related to the development of hybrid perovskite solar cells (HPSCs). Researchers will synthesize a new and

  4. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  5. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  6. NREL Solar Cell Wins Federal Technology Transfer Prize - News Releases |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL Solar Cell Wins Federal Technology Transfer Prize May 7, 2009 A new class of ultra-light, high-efficiency solar cells developed by the U.S. Department of Energy's National Renewable Energy Laboratory has been awarded a national prize for the commercialization of federally funded research. The Inverted Metamorphic Multijunction (IMM) Solar Cell was named a winner of the 2009 Award for Excellence in Technology Transfer by the Federal Laboratory Consortium for Technology Transfer. The

  7. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  8. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  9. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  10. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  11. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Wednesday, 26 October 2005 00:00 Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a

  12. Third-Generation Solar Cells Using Optical Rectenna - Energy...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The energy producing aspect of the photovoltaic ... of the electricity into direct current through an array of solar cells. ... focuses on low production costs using thin ...

  13. Alan J. Heeger, Conductive Polymers, and Plastic Solar Cells

    Office of Scientific and Technical Information (OSTI)

    Alan J. Heeger, Conductive Polymers, and Plastic Solar Cells Resources with Additional Information Patents Videos After receiving 'his physics Ph.D. at the University of...

  14. Simple Method Quantifies Recombination Pathways in Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-09-01

    NREL's analytic equation uses open-circuit voltage data to determine how much recombination occurs via different channels in a solar cell.

  15. Nanocrystal Solar Cells Squeeze Extra Juice Out of Sunlight ...

    Office of Science (SC) Website

    Nanocrystal Solar Cells Squeeze Extra Juice Out of Sunlight Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities ...

  16. Boosting Accuracy of Testing Multijunction Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2015-01-01

    This NREL Highlight describes research into a more precise technology for measuring efficiency of concentrating solar cells, which will enable the industry to advance.

  17. Thinner Film Silicon Solar Cells - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    thin film silicon solar cells with a potential increase in photon energy conversion of up to 20%, a significant improvement over conventional thin film photovoltaic technologies. ...

  18. Heterojunction for Multi-Junction Solar Cells - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Advanced Materials Find More Like This Return to Search Heterojunction for Multi-Junction Solar Cells Sandia National Laboratories Contact SNL About This Technology...

  19. Organizing and Strategizing a Local/Regional Solar Effort | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Organizing and Strategizing a Local/Regional Solar Effort Organizing and Strategizing a Local/Regional Solar Effort This webinar, "Organizing and Strategizing A Local/Regional Solar Effort," was originally presented on June 14, 2013 as part of the DOE SunShot Initiative's Solar Action Webinar Series. This includes presentations by a number of the program's grant partners, including three cities and one corporate partner, to provide participants' perspectives and present

  20. Reducing the Cost of Solar Cells

    SciTech Connect (OSTI)

    Scanlon, B.

    2012-04-01

    Solar-powered electricity prices could soon approach those of power from coal or natural gas thanks to collaborative research with solar startup Ampulse Corporation at the National Renewable Energy Laboratory. Silicon wafers account for almost half the cost of today's solar photovoltaic panels, so reducing or eliminating wafer costs is essential to bringing prices down. Current crystalline silicon technology converts energy in a highly efficient manner; however, that technology is manufactured with processes that could stand some improvement. The industry needs a method that is less complex, creates less waste and uses less energy. First, half the refined silicon is lost as dust in the wafer-sawing process, driving module costs higher. Wafers are sawn off of large cylindrical ingots, or boules, of silicon. A typical 2-meter boule loses as many as 6,000 potential wafers during sawing. Second, the wafers produced are much thicker than necessary. To efficiently convert sunlight into electricity, the wafers need be only one-tenth the typical thickness. NREL, the Oak Ridge National Laboratory and Ampulse have partnered on an approach to eliminate this waste and dramatically lower the cost of the finished solar panels. By using a chemical vapor deposition process to grow the silicon on inexpensive foil, Ampulse is able to make the solar cells just thick enough to convert most of the solar energy into electricity. No more sawdust - and no more wasting refined silicon materials. NREL developed the technology to grow high-quality silicon and ORNL developed the metal foil that has the correct crystal structure to support that growth. Ampulse is installing a pilot manufacturing line in NREL's Process Development Integration Laboratory, where solar companies can work closely with lab scientists on integrated equipment to answer pressing questions related to their technology development, as well as rapidly overcoming R and D challenges and risk. NREL's program is focused on transformative innovation in the domestic PV industry. With knowledge and expertise acquired from the PDIL pilot production line tools, Ampulse plans to design a full-scale production line to accommodate long rolls of metal foil. The Ampulse process 'goes straight from pure silicon-containing gas to high-quality crystal silicon film,' said Brent Nelson, the operational manager for the Process Development Integration Laboratory. 'The advantage is you can make the wafer just as thin as you need it - 10 microns or less.' Most of today's solar cells are made out of wafer crystalline silicon, though thin-film cells made of more exotic elements such as copper, indium, gallium, arsenic, cadmium, tellurium and others are making a strong push into the market. The advantage of silicon is its abundance, because it is derived from sand. Silicon's disadvantage is that purifying it into wafers suitable for solar cells can be expensive and energy intensive. Manufacturers add carbon and heat to sand to produce metallurgical-grade silicon, which is useful in other industries, but not yet suitable for making solar cells. So this metallurgical-grade silicon is then converted to pure trichlorosilane (SiCl3) or silane (SiH4) gas. Typically, the purified gas is then converted to create a silicon feedstock at 1,000 degrees Celsius. This feedstock is melted at 1,414 C and recrystallized into crystal ingots that are finally sawed into wafers. The Ampulse method differs in that it eliminates the last two steps in the traditional process and works directly with the silane gas growing only the needed silicon right onto a foil substrate. A team of NREL scientists had developed a way to use a process called hot-wire chemical vapor deposition to thicken silicon wafers with near perfect crystal structure. Using a hot tungsten filament much like the one found in an incandescent light bulb, the silane gas molecules are broken apart and deposited onto the wafer using the chemical vapor deposition technique at about 700 C - a much lower temperature than needed to make the wafer. The hot filament dec

  1. Laser processing technique for fabricating series-connected and tandem junction series-connected solar cells into a solar battery

    DOE Patents [OSTI]

    Hanak, Joseph J. (Lawrenceville, NJ)

    1981-01-01

    A method of fabricating series-connected and tandem junction series-connected solar cells into a solar battery with laser scribing.

  2. Laser beam apparatus and method for analyzing solar cells

    DOE Patents [OSTI]

    Staebler, David L. (Lawrenceville, NJ)

    1980-01-01

    A laser beam apparatus and method for analyzing, inter alia, the current versus voltage curve at the point of illumination on a solar cell and the open circuit voltage of a solar cell. The apparatus incorporates a lock-in amplifier, and a laser beam light chopper which permits the measurement of the AC current of the solar cell at an applied DC voltage at the position on the solar cell where the cell is illuminated and a feedback scheme which permits the direct scanning measurements of the open circuit voltage. The accuracy of the measurement is a function of the intensity and wavelength of the laser light with respect to the intensity and wavelength distribution of sunlight and the percentage the dark current is at the open circuit voltage to the short circuit current of the solar cell.

  3. AstroPower-DOE Collaboration Sets Solar Cell Record

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    cell by the company in 1995. AstroPower is the only ... low-cost Silicon-Film continuous sheet process. ... striking a solar cell can be converted into electricity. ...

  4. Analytical determination of critical crack size in solar cells

    SciTech Connect (OSTI)

    Chen, C.P.

    1988-05-01

    Although solar cells usually have chips and cracks, no material specifications concerning the allowable crack size on solar cells are available for quality assurance and engineering design usage. Any material specifications that the cell manufacturers use were developed for cosmetic reasons that have no technical basis. Therefore, the Applied Solar Energy Corporation (ASEC) has sponsored a continuing program for the fracture mechanics evaluation of GaAs. Fracture mechanics concepts were utilized to develop an analytical model that can predict the critical crack size of solar cells. This model indicates that the edge cracks of a solar cell are more critical than its surface cracks. In addition, the model suggests that the material specifications on the allowable crack size used for Si solar cells should not be applied to GaAs solar cells. The analytical model was applied to Si and GaAs solar cells, but it would also be applicable to the semiconductor wafers of other materials, such as a GaAs thin film on a Ge substrate, using appropriate input data.

  5. CRADA Final Report: Process development for hybrid solar cells

    SciTech Connect (OSTI)

    Ager, Joel W

    2011-02-14

    TCF funding of a CRADA between LBNL and RSLE leveraged RSLE's original $1M investment in LBNL research and led to development of a solar cell fabrication process that will bring the high efficiency, high voltage hybrid tandem solar cell closer to commercialization. RSLE has already built a pilot line at its Phoenix, Arizona site.

  6. Solar Foundational Program to Advance Cell Efficiency Round 2 | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Photovoltaics » Solar Foundational Program to Advance Cell Efficiency Round 2 Solar Foundational Program to Advance Cell Efficiency Round 2 The SunShot Foundational Program to Advance Cell Efficiency (F-PACE) aims to increase the efficiency of photovoltaic (PV) cells achieved in the laboratory and on manufacturing lines. Launched in September 2011, the first round of the F-PACE program supported 18 research projects over a 36-month performance period. These efforts laid the

  7. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In Situ X-Ray Scattering Helps Optimize Printed Solar Cells In Situ X-Ray Scattering Helps Optimize Printed Solar Cells Print Wednesday, 25 February 2015 00:00 Plastic solar cells...

  8. GaP/Silicon Tandem Solar Cell with Extended Temperature Range...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    crystalline silicon (Si) substrate, offering lower weight and lower cost. GRC's multi-junction solar cell has bottom solar cell junctions of silicon and a top solar cell junction...

  9. High-Efficiency Solar Cell Concepts: Physics, Materials, and Devices

    SciTech Connect (OSTI)

    Mascarenhas, A.; Francoeur, S.; Seong, M. J.; Fluegel, B.; Zhang, Y.; Wanlass, M. W.

    2005-01-01

    Over the past three decades, significant progress has been made in the area of high-efficiency multijunction solar cells, with the effort primarily directed at current-matched solar cells in tandem. The key materials issues here have been obtaining semiconductors with the required bandgaps for sequential absorption of light in the solar spectrum and that are lattice matched to readily available substrates. The GaInP/GaAs/Ge cell is a striking example of success achieved in this area. Recently, several new approaches for high-efficiency solar cell design have emerged, that involve novel methods for tailoring alloy bandgaps, as well as alternate technologies for hetero-epitaxy of III-V's on Si. The advantages and difficulties expected to be encountered with each approach will be discussed, addressing both the materials issues and device physics whilst contrasting them with other fourth-generation solar cell concepts.

  10. Solar cells incorporating light harvesting arrays

    DOE Patents [OSTI]

    Lindsey, Jonathan S.; Meyer, Gerald J.

    2003-07-22

    A solar cell incorporates a light harvesting array that comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: ##EQU1## wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2 ; and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).

  11. Efficiency of silicon solar cells containing chromium

    DOE Patents [OSTI]

    Frosch, Robert A. Administrator of the National Aeronautics and Space; Salama, Amal M.

    1982-01-01

    Efficiency of silicon solar cells containing about 10.sup.15 atoms/cm.sup.3 of chromium is improved about 26% by thermal annealing of the silicon wafer at a temperature of 200.degree. C. to form chromium precipitates having a diameter of less than 1 Angstrom. Further improvement in efficiency is achieved by scribing laser lines onto the back surface of the wafer at a spacing of at least 0.5 mm and at a depth of less than 13 micrometers to preferentially precipitate chromium near the back surface and away from the junction region of the device. This provides an economical way to improve the deleterious effects of chromium, one of the impurities present in metallurgical grade silicon material.

  12. Solar cells incorporating light harvesting arrays

    DOE Patents [OSTI]

    Lindsey, Jonathan S. (Raleigh, NC); Meyer, Gerald J. (Baltimore, MD)

    2002-01-01

    A solar cell incorporates a light harvesting array that comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: X.sup.1.paren open-st.X.sup.m+1).sub.m (I) wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2 ; and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).

  13. World-Record Solar Cell a Step Closer to Cheap Solar Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    World-Record Solar Cell a Step Closer to Cheap Solar Energy For more information contact: George Douglas (303) 275-4096 e:mail: george_douglas@nrel.gov Golden, Colo., Feb. 25, 1999 — Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) recently took another step toward reduced costs and increased competitiveness for solar energy by setting a world record for thin-film solar cell efficiency. The measurement of 18.8 percent efficiency for the copper indium

  14. Solar Foundational Program to Advance Cell Efficiency Round 1 | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Photovoltaics » Solar Foundational Program to Advance Cell Efficiency Round 1 Solar Foundational Program to Advance Cell Efficiency Round 1 The first round of the Foundational Program to Advance Cell Efficiency (F-PACE) program supported 18 projects working to create the technical foundation for significant increases in photovoltaic (PV) efficiency. Combining both the technical and funding resources of DOE and the National Science Foundation, this research investment worked toward

  15. Effects of angular confinement and concentration to realistic solar cells

    SciTech Connect (OSTI)

    Höhn, O. Kraus, T.; BlÀsi, B.; Schwarz, U. T.

    2015-01-21

    In standard solar cells, light impinges under a very small angular range, whereas the solar cell emits light into the whole half space. Due to this expansion of etendué, entropy is generated, which limits the maximal efficiency of solar cells. This limit can be overcome by either increasing the angle of incidence by concentration or by decreasing the angle of emission by an angularly confining element or by a combination of both. In an ideal solar cell with radiative recombination as the only loss mechanism, angular confinement and concentration are thermodynamically equivalent. It is shown that concentration in a device, where non-radiative losses such as Shockley-Read-Hall and Auger recombination are considered, is not equivalent to angular confinement. As soon as non-radiative losses are considered, the gain in efficiency due to angular confinement drops significantly in contrast to the gain caused by concentration. With the help of detailed balance calculations, it is furthermore shown that angular confinement can help to increase the efficiency of solar cells under concentrated sunlight even if no measurable gain is expected for the solar cell under 1-sun-illumination. Our analysis predicts a relative gain of 3.14% relative in efficiency for a realistic solar cell with a concentration factor of 500.

  16. Cost-Effective Replacement for Iodide in Dye-Sensitized Solar Cells -

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Innovation Portal Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Cost-Effective Replacement for Iodide in Dye-Sensitized Solar Cells Colorado State University Contact CSU About This Technology Publications: PDF Document Publication Electron Transfer Mediator Summary (236 KB) Cross-section of solar cell Cross-section of solar cell Technology Marketing SummaryDye-sensitized solar cells (DSSCs) are used to create electrical energy from sunlight. The cell has

  17. On-line, Continuous Monitoring in Solar Cell and Fuel Cell Manufacturing

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using Spectral Reflectance Imaging - Energy Innovation Portal Solar Photovoltaic Solar Photovoltaic Industrial Technologies Industrial Technologies Hydrogen and Fuel Cell Hydrogen and Fuel Cell Find More Like This Return to Search On-line, Continuous Monitoring in Solar Cell and Fuel Cell Manufacturing Using Spectral Reflectance Imaging National Renewable Energy Laboratory Contact NREL About This Technology Prototype Setup Prototype Setup Grain orientation map of a 156-mm x 156-mm mc-Si

  18. Accelerated aging of GaAs concentrator solar cells

    SciTech Connect (OSTI)

    Gregory, P.E.

    1982-04-01

    An accelerated aging study of AlGaAs/GaAs solar cells has been completed. The purpose of the study was to identify the possible degradation mechanisms of AlGaAs/GaAs solar cells in terrestrial applications. Thermal storage tests and accelerated AlGaAs corrosion studies were performed to provide an experimental basis for a statistical analysis of the estimated lifetime. Results of this study suggest that a properly designed and fabricated AlGaAs/GaAs solar cell can be mechanically rugged and environmentally stable with projected lifetimes exceeding 100 years.

  19. Modeling of the electronic transport in multijunction solar cells

    SciTech Connect (OSTI)

    Rau, U.; Goldbach, M.

    1994-12-31

    Simulations of the electrical transport in multijunction thin-film solar cells made from polycrystalline silicon are presented. The authors investigate the effect of the grain size on the efficiency of the multijunction solar cell. Here, they concentrate on micro crystalline material with a high recombination velocity at the grain boundaries of 10{sup 4}cm/s. Typical results of their calculations demonstrate that based on the multijunction design structure consisting of 8 or more layers efficiencies of 14% may be obtained from 12--20 {micro}m thick solar cells.

  20. Voltage-matched configurations for multijunction solar cells

    SciTech Connect (OSTI)

    Gee, J.M.

    1987-01-01

    Novel methods for interconnecting the subcells of a multijunction solar cell are investigated. The subcells are connected in parallel in these new methods. The bandgaps of the subcells must be selected for matched voltages when operated in parallel. We refer to multijunction solar cells with the subcells connected in parallel as having a voltage-matched configuration. Computer analyses of multijunction solar cells with a voltage-matched configuration and with series-connected subcells were performed. Roughly, the same performance with either approach for a multijunction cell with optimized bandgaps was found. Several advantages for the voltage-matched configuration relative to multijunction solar cells with series-connected subcells were identified, including wider selection of bandgaps for optimal performance, less sensitivity to radiation damage, and less sensitivity to spectral variations.

  1. Preparation Of Copper Indium Gallium Diselenide Films For Solar Cells

    DOE Patents [OSTI]

    Bhattacharya, Raghu N.; Contreras, Miguel A.; Keane, James; Tennant, Andrew L. , Tuttle, John R.; Ramanathan, Kannan; Noufi, Rommel

    1998-08-08

    High quality thin films of copper-indium-gallium-diselenide useful in the production of solar cells are prepared by electrodepositing at least one of the constituent metals onto a glass/Mo substrate, followed by physical vapor deposition of copper and selenium or indium and selenium to adjust the final stoichiometry of the thin film to approximately Cu(In,Ga)Se.sub.2. Using an AC voltage of 1-100 KHz in combination with a DC voltage for electrodeposition improves the morphology and growth rate of the deposited thin film. An electrodeposition solution comprising at least in part an organic solvent may be used in conjunction with an increased cathodic potential to increase the gallium content of the electrodeposited thin film.

  2. Effects of cell area on the performance of dye sensitized solar cell

    SciTech Connect (OSTI)

    Khatani, Mehboob E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Mohamed, Norani Muti E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Hamid, Nor Hisham E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Sahmer, Ahmad Zahrin E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Samsudin, Adel E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com

    2014-10-24

    Dye sensitized solar cells (DSCs) have significant advantage over the current silicon cells by having low manufacturing cost and potentially high conversion efficiency. Therefore, DSCs are expected to be used as the next generation solar cell device that covers wide range of new applications. In order to achieve highly efficient DSCs for practical application, study on the effect of increasing the cell’s area on the performance of dye sensitized solar need to be carried out. Three different DSC cell areas namely, 1, 12.96 and 93.5 cm{sup 2} respectively were fabricated and analyzed through solar simulator and electrochemical impedance spectroscopy (EIS). From the analysis of electrochemical impedance spectroscopy (EIS), it was observed that the cell’s electron lifetime was influenced significantly by the cell’s area. Although the collection efficiency of all cells recorded to be approximately 100% but higher recombination rate with increased cell area reduced the performance of the cell.

  3. Method for forming indium oxide/n-silicon heterojunction solar cells

    DOE Patents [OSTI]

    Feng, Tom (Morris Plains, NJ); Ghosh, Amal K. (New Providence, NJ)

    1984-03-13

    A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

  4. Current- and lattice-matched tandem solar cell

    DOE Patents [OSTI]

    Olson, J.M.

    1985-10-21

    A multijunction (cascade) tandem photovoltaic solar cell device is fabricated of a Ga/sub x/In/sub 1-x/P (0.505 equal to or less than x equal to or less than 0.515) top cell semiconductor lattice-matched to a GaAs bottom cell semiconductor at a low resistance heterojunction, preferably a p/sup +//n/sup +/ heterojunction between the cells. The top and bottom cells are both lattice-matched and current-matched for high efficiency solar radiation conversion to electrical energy.

  5. Organic fuel cells and fuel cell conducting sheets

    DOE Patents [OSTI]

    Masel, Richard I. (Champaign, IL); Ha, Su (Champaign, IL); Adams, Brian (Savoy, IL)

    2007-10-16

    A passive direct organic fuel cell includes an organic fuel solution and is operative to produce at least 15 mW/cm.sup.2 when operating at room temperature. In additional aspects of the invention, fuel cells can include a gas remover configured to promote circulation of an organic fuel solution when gas passes through the solution, a modified carbon cloth, one or more sealants, and a replaceable fuel cartridge.

  6. NREL Invention Speeds Solar Cell Quality Testing for Industry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Renewable Energy within the U.S. Department of Energy... fraction of the time required by the current method, allowing its use on every solar cell passing through a production line. ...

  7. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    technology that will help realize the intrinsic potential of these materials. Solar Panels To Go Photovoltaic cells are a key component of most visions of a clean-energy...

  8. Structure of All-Polymer Solar Cells Impedes Efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in model all-polymer solar cells is caused by domains that are too large and interfaces that are not sharp enough. This insight will lead to new approaches to all-polymer...

  9. Investigation of the texture surface silicon solar cell

    SciTech Connect (OSTI)

    Rongqiang, C.; Huilan, Q.

    1983-10-01

    The optical and electrical properties of the texture surface silicon solar cell are analyzed and discussed. A new method of etching a texture surface by LiOH is presented and the mechanism of etching a texture surface is investigated.

  10. Post-Deposition Treatment Boosts CIGS Solar Cell Performance...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Se-containing precursors. These experiments led to a 16.2%-efficient solar cell fabricated from the CuGa In stacked metal precursor. But the goal was to increase the...

  11. Enhanced light absorption of solar cells and photodetectors by diffraction

    DOE Patents [OSTI]

    Zaidi, Saleem H.; Gee, James M.

    2005-02-22

    Enhanced light absorption of solar cells and photodetectors by diffraction is described. Triangular, rectangular, and blazed subwavelength periodic structures are shown to improve performance of solar cells. Surface reflection can be tailored for either broadband, or narrow-band spectral absorption. Enhanced absorption is achieved by efficient optical coupling into obliquely propagating transmitted diffraction orders. Subwavelength one-dimensional structures are designed for polarization-dependent, wavelength-selective absorption in solar cells and photodetectors, while two-dimensional structures are designed for polarization-independent, wavelength-selective absorption therein. Suitable one and two-dimensional subwavelength periodic structures can also be designed for broadband spectral absorption in solar cells and photodetectors. If reactive ion etching (RIE) processes are used to form the grating, RIE-induced surface damage in subwavelength structures can be repaired by forming junctions using ion implantation methods. RIE-induced surface damage can also be removed by post RIE wet-chemical etching treatments.

  12. Approaches to Future Generation Photovoltaics and Solar Fuels: Quantum Dots, Arrays, and Quantum Dot Solar Cells

    SciTech Connect (OSTI)

    Semonin, O.; Luther, J.; Beard, M.; Johnson, J.; Gao, J.; Nozik, A.

    2012-01-01

    One potential, long-term approach to more efficient and lower cost future generation solar cells for solar electricity and solar fuels is to utilize the unique properties of quantum dots (QDs) to control the relaxation pathways of excited states to enhance multiple exciton generation (MEG). We have studied MEG in close-packed PbSe QD arrays where the QDs are electronically coupled in the films and thus exhibit good transport while still maintaining quantization and MEG. We have developed simple, all-inorganic solution-processable QD solar cells that produce large short-circuit photocurrents and power conversion efficiencies above 5% via nanocrystalline p-n junctions. These solar cells show QYs for photocurrent that exceed 100% in the photon energy regions where MEG is possible; the photocurrent MEG QYs as a function of photon energy match those determined via time-resolved spectroscopy Recent analyses of the major effect of MEG combined with solar concentration on the conversion efficiency of solar cells will also be discussed.

  13. NREL Theorizes Defects Could Improve Solar Cells - News Releases | NREL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL Theorizes Defects Could Improve Solar Cells January 12, 2016 Drawing of of a good defect. Schematic of a 'good' defect (red cross), which helps collection of electrons from photo-absorber (n-Si), and blocks the holes, hence suppresses carriers recombination. Scientists at the Energy Department's National Renewable Energy Laboratory (NREL) are studying what may seem paradoxical - certain defects in silicon solar cells may actually improve their performance. The findings run counter to

  14. NREL Licenses Technology to Increase Solar Cell Efficiency - News Releases

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | NREL NREL Licenses Technology to Increase Solar Cell Efficiency Natcore to develop 'black silicon' solar cells based on award-winning innovation December 20, 2011 The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) announced today that Natcore Technology Inc. has been granted a patent license agreement to develop a line of black silicon products. Natcore and NREL also will enter a Cooperative Research and Development Agreement (CRADA) to develop commercial

  15. 15.01.16 RH Perovskite Solar Cells - JCAP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fabrication of High Efficiency Perovskite Solar Cells Li, Y., Cooper, J. K., Buonsanti, R., Giannini, G., Liu, Y., Toma, F. M. & Sharp, I. D. Fabrication of Planar Heterojunction Perovskite Solar Cells by Controlled Low-Pressure Vapor Annealing. J. Phys. Chem. Lett ., 6, 493-499, DOI: 10.1021/jz502720a (2015). Scientific Achievement A new synthetic method based on low-pressure and reduced-temperature vapor annealing was developed and demonstrated to yield efficient hybrid halide perovskites

  16. California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Award | Department of Energy TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award August 16, 2013 - 10:41am Addthis California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award TetraSun, in partnership with the National Renewable Energy Laboratory, developed a novel crystalline silicon photovoltaic (PV) cell architecture and manufacturing process that achieves

  17. Intermediate band solar cells: Recent progress and future directions

    SciTech Connect (OSTI)

    Okada, Y. Tamaki, R.; Farrell, D. J.; Yoshida, K.; Ahsan, N.; Shoji, Y.; Sogabe, T.; Ekins-Daukes, N. J. Yoshida, M.; Pusch, A.; Hess, O.; Phillips, C. C.; Kita, T.; Guillemoles, J.-F.

    2015-06-15

    Extensive literature and publications on intermediate band solar cells (IBSCs) are reviewed. A detailed discussion is given on the thermodynamics of solar energy conversion in IBSCs, the device physics, and the carrier dynamics processes with a particular emphasis on the two-step inter-subband absorption/recombination processes that are of paramount importance in a successful implementation high-efficiency IBSC. The experimental solar cell performance is further discussed, which has been recently demonstrated by using highly mismatched alloys and high-density quantum dot arrays and superlattice. IBSCs having widely different structures, materials, and spectral responses are also covered, as is the optimization of device parameters to achieve maximum performance.

  18. NREL Studies Carrier Separation and Transport in Perovskite Solar Cells

    SciTech Connect (OSTI)

    2016-01-01

    NREL scientists studied charge separation and transport in perovskite solar cells by determining the junction structure across the solar device using the nanoelectrical characterization technique of Kelvin probe force microscopy. The distribution of electrical potential across both planar and porous devices demonstrates a p-n junction structure at the interface between titanium dioxide and perovskite. In addition, minority-carrier transport within the devices operates under diffusion/drift. Clarifying the fundamental junction structure provides significant guidance for future research and development. This NREL study points to the fact that improving carrier mobility is a critical factor for continued efficiency gains in perovskite solar cells.

  19. Photo of the Week: Record-Breaking Solar Cells | Department of Energy

    Energy Savers [EERE]

    Record-Breaking Solar Cells Photo of the Week: Record-Breaking Solar Cells December 7, 2012 - 2:27pm Addthis Solar Junction, in partnership with NREL, has developed solar cells that reach a record-breaking 44 percent efficiency -- meaning that more than 40 percent of the sunlight the solar cells are exposed to is converted into electrical energy. In this photo, an operator inspects a photolithography tool used to manufacture these solar cells. | Photo by Daniel Derkacs/SolarJunction. Solar

  20. Thermodynamics of photon-enhanced thermionic emission solar cells

    SciTech Connect (OSTI)

    Reck, Kasper; Hansen, Ole

    2014-01-13

    Photon-enhanced thermionic emission (PETE) cells in which direct photon energy as well as thermal energy can be harvested have recently been suggested as a new candidate for high efficiency solar cells. Here, we present an analytic thermodynamical model for evaluation of the efficiency of PETE solar cells including an analysis of the entropy production due to thermionic emission of general validity. The model is applied to find the maximum efficiency of a PETE cell for given cathode and anode work functions and temperatures.

  1. EERE Success Story-California: TetraCell Silicon Solar Cell Improves

    Office of Environmental Management (EM)

    Efficiency, Wins R&D 100 Award | Department of Energy TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award EERE Success Story-California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award August 16, 2013 - 10:41am Addthis EERE Success Storyñ€”California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award TetraSun, in partnership with the National Renewable Energy Laboratory, developed a novel crystalline silicon

  2. Monolithically interconnected GaAs solar cells: A new interconnection technology for high voltage solar cell output

    SciTech Connect (OSTI)

    Dinetta, L.C.; Hannon, M.H.

    1995-10-01

    Photovoltaic linear concentrator arrays can benefit from high performance solar cell technologies being developed at AstroPower. Specifically, these are the integration of thin GaAs solar cell and epitaxial lateral overgrowth technologies with the application of monolithically interconnected solar cell (MISC) techniques. This MISC array has several advantages which make it ideal for space concentrator systems. These are high system voltage, reliable low cost monolithically formed interconnections, design flexibility, costs that are independent of array voltage, and low power loss from shorts, opens, and impact damage. This concentrator solar cell will incorporate the benefits of light trapping by growing the device active layers over a low-cost, simple, PECVD deposited silicon/silicon dioxide Bragg reflector. The high voltage-low current output results in minimal 12R losses while properly designing the device allows for minimal shading and resistance losses. It is possible to obtain open circuit voltages as high as 67 volts/cm of solar cell length with existing technology. The projected power density for the high performance device is 5 kW/m for an AMO efficiency of 26% at 1 5X. Concentrator solar cell arrays are necessary to meet the power requirements of specific mission platforms and can supply high voltage power for electric propulsion systems. It is anticipated that the high efficiency, GaAs monolithically interconnected linear concentrator solar cell array will enjoy widespread application for space based solar power needs. Additional applications include remote man-portable or ultra-light unmanned air vehicle (UAV) power supplies where high power per area, high radiation hardness and a high bus voltage or low bus current are important. The monolithic approach has a number of inherent advantages, including reduced cost per interconnect and increased reliability of array connections. There is also a high potential for a large number of consumer products.

  3. Method Of Making Solar Collectors By In-Situ Encapsulation Of Solar Cells

    DOE Patents [OSTI]

    Carrie, Peter J.; Chen, Kingsley D. D.

    2000-10-24

    A method of making solar collectors by encapsulating photovoltaic cells within a base of an elongated solar collector wherein heat and pressure are applied to the cells in-situ, after an encapsulating material has been applied. A tool is fashioned having a bladder expandable under gas pressure, filling a region of the collector where the cells are mounted. At the same time, negative pressure is applied outside of the bladder, enhancing its expansion. The bladder presses against a platen which contacts the encapsulated cells, causing outgassing of the encapsulant, while heat cures the encapsulant. After curing, the bladder is deflated and the tool may be removed from the collector and base and reflective panels put into place, if not already there, thereby allowing the solar collector to be ready for use.

  4. Development of an electronic device quality aluminum antimonide (AlSb) semiconductor for solar cell applications

    DOE Patents [OSTI]

    Sherohman, John W; Yee, Jick Hong; Combs, III, Arthur W

    2014-11-11

    Electronic device quality Aluminum Antimonide (AlSb)-based single crystals produced by controlled atmospheric annealing are utilized in various configurations for solar cell applications. Like that of a GaAs-based solar cell devices, the AlSb-based solar cell devices as disclosed herein provides direct conversion of solar energy to electrical power.

  5. A high intensity solar cell invention: The edge-illuminated vertical multi-junction (VNJ) solar cell

    SciTech Connect (OSTI)

    Sater, B.L.

    1992-08-07

    This report contains a summary of a High Intensity Solar Cell (HI Cell) development carried out under the NIST/DOE Energy-Related Invention Program. The HI Cell, or Edge-Illuminated vertical Multi-junction Solar Cell, eliminates most major problems encountered with other concentrator solar cell designs. Its high voltage and low series resistance features make it ideally suited for efficient operation at high intensities. Computer modeling shows efficiencies near 30% at 500 suns intensity are possible with state-of-art processing. Development of a working model was largely successful before encountering an unexpected problem during the last fabrication step with the anti-reflection coating. Unfortunately, funding was exhausted before its resolution. Recommendations are made to resolve the AR coating problem and to integrate all the knowledge gained during this development into a viable prototype model. The invention will provide the technical and economic performance needed to make photovoltaic systems cost-effective for wide use.

  6. A high intensity solar cell invention: The edge-illuminated vertical multi-junction (VNJ) solar cell. Final report

    SciTech Connect (OSTI)

    Sater, B.L.

    1992-08-07

    This report contains a summary of a High Intensity Solar Cell (HI Cell) development carried out under the NIST/DOE Energy-Related Invention Program. The HI Cell, or Edge-Illuminated vertical Multi-junction Solar Cell, eliminates most major problems encountered with other concentrator solar cell designs. Its high voltage and low series resistance features make it ideally suited for efficient operation at high intensities. Computer modeling shows efficiencies near 30% at 500 suns intensity are possible with state-of-art processing. Development of a working model was largely successful before encountering an unexpected problem during the last fabrication step with the anti-reflection coating. Unfortunately, funding was exhausted before its resolution. Recommendations are made to resolve the AR coating problem and to integrate all the knowledge gained during this development into a viable prototype model. The invention will provide the technical and economic performance needed to make photovoltaic systems cost-effective for wide use.

  7. Three dimensional amorphous silicon/microcrystalline silicon solar cells

    DOE Patents [OSTI]

    Kaschmitter, James L.

    1996-01-01

    Three dimensional deep contact amorphous silicon/microcrystalline silicon (a-Si/.mu.c-Si) solar cells which use deep (high aspect ratio) p and n contacts to create high electric fields within the carrier collection volume material of the cell. The deep contacts are fabricated using repetitive pulsed laser doping so as to create the high aspect p and n contacts. By the provision of the deep contacts which penetrate the electric field deep into the material where the high strength of the field can collect many of the carriers, thereby resulting in a high efficiency solar cell.

  8. Three dimensional amorphous silicon/microcrystalline silicon solar cells

    DOE Patents [OSTI]

    Kaschmitter, J.L.

    1996-07-23

    Three dimensional deep contact amorphous silicon/microcrystalline silicon (a-Si/{micro}c-Si) solar cells are disclosed which use deep (high aspect ratio) p and n contacts to create high electric fields within the carrier collection volume material of the cell. The deep contacts are fabricated using repetitive pulsed laser doping so as to create the high aspect p and n contacts. By the provision of the deep contacts which penetrate the electric field deep into the material where the high strength of the field can collect many of the carriers, thereby resulting in a high efficiency solar cell. 4 figs.

  9. Laminated photovoltaic modules using back-contact solar cells

    DOE Patents [OSTI]

    Gee, James M. (Albuquerque, NM); Garrett, Stephen E. (Albuquerque, NM); Morgan, William P. (Albuquerque, NM); Worobey, Walter (Albuquerque, NM)

    1999-09-14

    Photovoltaic modules which comprise back-contact solar cells, such as back-contact crystalline silicon solar cells, positioned atop electrically conductive circuit elements affixed to a planar support so that a circuit capable of generating electric power is created. The modules are encapsulated using encapsulant materials such as EVA which are commonly used in photovoltaic module manufacture. The module designs allow multiple cells to be electrically connected in a single encapsulation step rather than by sequential soldering which characterizes the currently used commercial practices.

  10. Thin film solar cell configuration and fabrication method

    DOE Patents [OSTI]

    Menezes, Shalini

    2009-07-14

    A new photovoltaic device configuration based on an n-copper indium selenide absorber and a p-type window is disclosed. A fabrication method to produce this device on flexible or rigid substrates is described that reduces the number of cell components, avoids hazardous materials, simplifies the process steps and hence the costs for high volume solar cell manufacturing.

  11. Electron Transfer Dynamics in Efficient Molecular Solar Cells

    SciTech Connect (OSTI)

    Meyer, Gerald John

    2014-10-01

    This research provided new mechanistic insights into surface mediated photochemical processes relevant to solar energy conversion. In this past three years our research has focused on oxidation photo-redox chemistry and on the role surface electric fields play on basic spectroscopic properties of molecular-semiconductor interfaces. Although this research as purely fundamental science, the results and their interpretation have relevance to applications in dye sensitized and photogalvanic solar cells as well as in the storage of solar energy in the form of chemical bonds.

  12. Upside-Down Solar Cell Achieves Record Efficiencies (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2010-12-01

    The inverted metamorphic multijunction (IMM) solar cell is an exercise in efficient innovation - literally, as the technology boasted the highest demonstrated efficiency for converting sunlight into electrical energy at its debut in 2005. Scientists at the National Renewable Energy Laboratory (NREL) inverted the conventional photovoltaic (PV) structure to revolutionary effect, achieving solar conversion efficiencies of 33.8% and 40.8% under one-sun and concentrated conditions, respectively.

  13. Colloidal quantum dot solar cells on curved and flexible substrates

    SciTech Connect (OSTI)

    Kramer, Illan J.; Moreno-Bautista, Gabriel; Minor, James C.; Kopilovic, Damir; Sargent, Edward H.

    2014-10-20

    Colloidal quantum dots (CQDs) are semiconductor nanocrystals synthesized with, processed in, and deposited from the solution phase, potentially enabling low-cost, facile manufacture of solar cells. Unfortunately, CQD solar cell reports, until now, have only explored batch-processing methods—such as spin-coating—that offer limited capacity for scaling. Spray-coating could offer a means of producing uniform colloidal quantum dot films that yield high-quality devices. Here, we explore the versatility of the spray-coating method by producing CQD solar cells in a variety of previously unexplored substrate arrangements. The potential transferability of the spray-coating method to a roll-to-roll manufacturing process was tested by spray-coating the CQD active layer onto six substrates mounted on a rapidly rotating drum, yielding devices with an average power conversion efficiency of 6.7%. We further tested the manufacturability of the process by endeavoring to spray onto flexible substrates, only to find that spraying while the substrate was flexed was crucial to achieving champion performance of 7.2% without compromise to open-circuit voltage. Having deposited onto a substrate with one axis of curvature, we then built our CQD solar cells onto a spherical lens substrate having two axes of curvature resulting in a 5% efficient device. These results show that CQDs deposited using our spraying method can be integrated to large-area manufacturing processes and can be used to make solar cells on unconventional shapes.

  14. Method of making quasi-grain boundary-free polycrystalline solar cell structure and solar cell structure obtained thereby

    DOE Patents [OSTI]

    Gonzalez, Franklin N. (Gainesville, FL); Neugroschel, Arnost (Gainesville, FL)

    1984-02-14

    A new solar cell structure is provided which will increase the efficiency of polycrystalline solar cells by suppressing or completely eliminating the recombination losses due to the presence of grain boundaries. This is achieved by avoiding the formation of the p-n junction (or other types of junctions) in the grain boundaries and by eliminating the grain boundaries from the active area of the cell. This basic concept can be applied to any polycrystalline material; however, it will be most beneficial for cost-effective materials having small grains, including thin film materials.

  15. Method of making a back contacted solar cell

    DOE Patents [OSTI]

    Gee, J.M.

    1995-11-21

    A back-contacted solar cell is described having laser-drilled vias connecting the front-surface carrier-collector junction to an electrode grid on the back surface. The structure may also include a rear surface carrier-collector junction connected to the same grid. The substrate is connected to a second grid which is interdigitated with the first. Both grids are configured for easy series connection with neighboring cells. Several processes are disclosed to produce the cell. 2 figs.

  16. Method of making a back contacted solar cell

    DOE Patents [OSTI]

    Gee, James M. (Albuquerque, NM)

    1995-01-01

    A back-contacted solar cell having laser-drilled vias connecting the front-surface carrier-collector junction to an electrode grid on the back surface. The structure may also include a rear surface carrier-collector junction connected to the same grid. The substrate is connected to a second grid which is interdigitated with the first. Both grids are configured for easy series connection with neighboring cells. Several processes are disclosed to produce the cell.

  17. Quantum Dot Solar Cells with Multiple Exciton Generation

    SciTech Connect (OSTI)

    Hanna, M. C.; Beard, M. C.; Johnson, J. C.; Murphy, J.; Ellingson, R. J.; Nozik, A. J.

    2005-11-01

    We have measured the quantum yield of the multiple exciton generation (MEG) process in quantum dots (QDs) of the lead-salt semiconductor family (PbSe, PbTe, and PbS) using fs pump-probe transient absorption measurements. Very high quantum yields (up to 300%) for charge carrier generation from MEG have been measured in all of the Pb-VI QDs. We have calculated the potential maximum performance of various MEG QD solar cells in the detailed balance limit. We examined a two-cell tandem PV device with singlet fission (SF), QD, and normal dye (N) absorbers in the nine possible series-connected combinations to compare the tandem combinations and identify the combinations with the highest theoretical efficiency. We also calculated the maximum efficiency of an idealized single-gap MEG QD solar cell with M multiplications and its performance under solar concentration.

  18. New approaches for high-efficiency solar cells. Final report

    SciTech Connect (OSTI)

    Bedair, S.M.; El-Masry, N.A.

    1997-12-01

    This report summarizes the activities carried out in this subcontract. These activities cover, first the atomic layer epitaxy (ALE) growth of GaAs, AlGaAs and InGaP at fairly low growth temperatures. This was followed by using ALE to achieve high levels of doping both n-type and p-type required for tunnel junctions (Tj) in the cascade solar cell structures. Then the authors studied the properties of AlGaAs/InGaP and AlGaAs/GaAs tunnel junctions and their performances at different growth conditions. This is followed by the use of these tunnel junctions in stacked solar cell structures. The effect of these tunnel junctions on the performance of stacked solar cells was studied at different temperatures and different solar fluences. Finally, the authors studied the effect of different types of black surface fields (BSF), both p/n and n/p GaInP solar cell structures, and their potential for window layer applications. Parts of these activities were carried in close cooperation with Dr. Mike Timmons of the Research Triangle Institute.

  19. Substrate for thin silicon solar cells

    DOE Patents [OSTI]

    Ciszek, T.F.

    1995-03-28

    A photovoltaic device for converting solar energy into electrical signals comprises a substrate, a layer of photoconductive semiconductor material grown on said substrate, wherein the substrate comprises an alloy of boron and silicon, the boron being present in a range of from 0.1 to 1.3 atomic percent, the alloy having a lattice constant substantially matched to that of the photoconductive semiconductor material and a resistivity of less than 1{times}10{sup {minus}3} ohm-cm. 4 figures.

  20. Substrate for thin silicon solar cells

    DOE Patents [OSTI]

    Ciszek, Theodore F. (Evergreen, CO)

    1995-01-01

    A photovoltaic device for converting solar energy into electrical signals comprises a substrate, a layer of photoconductive semiconductor material grown on said substrate, wherein the substrate comprises an alloy of boron and silicon, the boron being present in a range of from 0.1 to 1.3 atomic percent, the alloy having a lattice constant substantially matched to that of the photoconductive semiconductor material and a resistivity of less than 1.times.10.sup.-3 ohm-cm.

  1. Process Development for High Voc CdTe Solar Cells

    SciTech Connect (OSTI)

    Ferekides, C. S.; Morel, D. L.

    2011-05-01

    This is a cumulative and final report for Phases I, II and III of this NREL funded project (subcontract # XXL-5-44205-10). The main research activities of this project focused on the open-circuit voltage of the CdTe thin film solar cells. Although, thin film CdTe continues to be one of the leading materials for large-scale cost-effective production of photovoltaics, the efficiency of the CdTe solar cells have been stagnant for the last few years. This report describes and summarizes the results for this 3-year research project.

  2. Fabrication of solar cells with counter doping prevention

    DOE Patents [OSTI]

    Dennis, Timothy D; Li, Bo; Cousins, Peter John

    2013-02-19

    A solar cell fabrication process includes printing of dopant sources over a polysilicon layer over backside of a solar cell substrate. The dopant sources are cured to diffuse dopants from the dopant sources into the polysilicon layer to form diffusion regions, and to crosslink the dopant sources to make them resistant to a subsequently performed texturing process. To prevent counter doping, dopants from one of the dopant sources are prevented from outgassing and diffusing into the other dopant source. For example, phosphorus from an N-type dopant source is prevented from diffusing to a P-type dopant source comprising boron.

  3. Thin film solar cell including a spatially modulated intrinsic layer

    DOE Patents [OSTI]

    Guha, Subhendu (Troy, MI); Yang, Chi-Chung (Troy, MI); Ovshinsky, Stanford R. (Bloomfield Hills, MI)

    1989-03-28

    One or more thin film solar cells in which the intrinsic layer of substantially amorphous semiconductor alloy material thereof includes at least a first band gap portion and a narrower band gap portion. The band gap of the intrinsic layer is spatially graded through a portion of the bulk thickness, said graded portion including a region removed from the intrinsic layer-dopant layer interfaces. The band gap of the intrinsic layer is always less than the band gap of the doped layers. The gradation of the intrinsic layer is effected such that the open circuit voltage and/or the fill factor of the one or plural solar cell structure is enhanced.

  4. Copper doped polycrystalline silicon solar cell

    DOE Patents [OSTI]

    Lovelace, Alan M. Administrator of the National Aeronautics and Space (La Canada, CA); Koliwad, Krishna M. (La Canada, CA); Daud, Taher (La Crescenta, CA)

    1981-01-01

    Photovoltaic cells having improved performance are fabricated from polycrystalline silicon containing copper segregated at the grain boundaries.

  5. Fabrication of heterojunction solar cells by improved tin oxide deposition on insulating layer

    DOE Patents [OSTI]

    Feng, Tom (Morris Plains, NJ); Ghosh, Amal K. (New Providence, NJ)

    1980-01-01

    Highly efficient tin oxide-silicon heterojunction solar cells are prepared by heating a silicon substrate, having an insulating layer thereon, to provide a substrate temperature in the range of about 300.degree. C. to about 400.degree. C. and thereafter spraying the so-heated substrate with a solution of tin tetrachloride in a organic ester boiling below about 250.degree. C. Preferably the insulating layer is naturally grown silicon oxide layer.

  6. Highly Mismatched Alloys for Intermediate Band Solar Cells

    SciTech Connect (OSTI)

    Walukiewicz, W.; Yu, K.M.; Wu, J.; Ager III, J.W.; Shan, W.; Scrapulla, M.A.; Dubon, O.D.; Becla, P.

    2005-03-21

    It has long been recognized that the introduction of a narrow band of states in a semiconductor band gap could be used to achieve improved power conversion efficiency in semiconductor-based solar cells. The intermediate band would serve as a ''stepping stone'' for photons of different energy to excite electrons from the valence to the conduction band. An important advantage of this design is that it requires formation of only a single p-n junction, which is a crucial simplification in comparison to multijunction solar cells. A detailed balance analysis predicts a limiting efficiency of more than 50% for an optimized, single intermediate band solar cell. This is higher than the efficiency of an optimized two junction solar cell. Using ion beam implantation and pulsed laser melting we have synthesized Zn{sub 1-y}Mn{sub y}O{sub x}Te{sub 1-x} alloys with x<0.03. These highly mismatched alloys have a unique electronic structure with a narrow oxygen-derived intermediate band. The width and the location of the band is described by the Band Anticrossing model and can be varied by controlling the oxygen content. This provides a unique opportunity to optimize the absorption of solar photons for best solar cell performance. We have carried out systematic studies of the effects of the intermediate band on the optical and electrical properties of Zn{sub 1-y}Mn{sub y}O{sub x}Te{sub 1-x} alloys. We observe an extension of the photovoltaic response towards lower photon energies, which is a clear indication of optical transitions from the valence to the intermediate band.

  7. Design of Molecular Solar Cells via Feedback from Soft X-ray Spectroscopy

    SciTech Connect (OSTI)

    Himpsel, Franz J.

    2015-06-12

    Spectroscopy with soft X-rays was used to develop new materials and novel designs for solar cells and artificial photosynthesis. In order to go beyond the widely-used trial-and-error approach of gradually improving a particular design, we started from the most general layout of a solar cell (or a photo-electrochemical device) and asked which classes of materials are promising for best performance. For example, the most general design of a solar cell consists of a light absorber, an electron donor, and an electron acceptor. These are characterized by four energy levels, which were measured by a combination of spectroscopic X-ray techniques. Tuning synchrotron radiation to the absorption edges of specific elements provided element- and bond-selectivity. The spectroscopic results were complemented by state-of-the-art calculations of the electronic states. These helped explaining the observed energy levels and the orbitals associated with them. The calculations were extended to a large class of materials (for example thousands of porphyrin dye complexes) in order to survey trends in the energy level structure. A few highlights serve as examples: 1) Organic molecules combining absorber, donor, and acceptor with atomic precision. 2) Exploration of highly p-doped diamond films as inert, transparent electron donors. 3) Surface-sensitive characterization of nanorod arrays used as photoanodes in water splitting. 4) Computational design of molecular complexes for efficient solar cells using two photons.

  8. GaNPAs Solar Cells Lattice-Matched To GaP: Preprint

    SciTech Connect (OSTI)

    Geisz, J. F.; Friedman, D. J.; Kurtz, S.

    2002-05-01

    This conference paper describes the III-V semiconductors grown on silicon substrates are very attractive for lower-cost, high-efficiency multijunction solar cells, but lattice-mismatched alloys that result in high dislocation densities have been unable to achieve satisfactory performance. GaNxP1-x-yAsy is a direct-gap III-V alloy that can be grown lattice-matched to Si when y= 4.7x - 0.1. We propose the use of lattice-matched GaNPAs on silicon for high-efficiency multijunction solar cells. We have grown GaNxP1-x-yAsy on GaP (with a similar lattice constant to silicon) by metal-organic chemical vapor phase epitaxy with direct band-gaps in the range of 1.5 to 2.0 eV. We demonstrate the performance of single-junction GaNxP1-x-yAsy solar cells grown on GaP substrates and discuss the prospects for the development of monolithic high-efficiency multijunction solar cells based on silicon substrates.

  9. Spatiotemporal organization of energy release events in the quiet solar corona

    SciTech Connect (OSTI)

    Uritsky, Vadim M.; Davila, Joseph M.

    2014-11-01

    Using data from the STEREO and SOHO spacecraft, we show that temporal organization of energy release events in the quiet solar corona is close to random, in contrast to the clustered behavior of flaring times in solar active regions. The locations of the quiet-Sun events follow the meso- and supergranulation pattern of the underling photosphere. Together with earlier reports of the scale-free event size statistics, our findings suggest that quiet solar regions responsible for bulk coronal heating operate in a driven self-organized critical state, possibly involving long-range Alfvénic interactions.

  10. Modelling and fabrication of high-efficiency silicon solar cells

    SciTech Connect (OSTI)

    Rohatgi, A.; Smith, A.W.; Salami, J.

    1991-10-01

    This report covers the research conducted on modelling and development of high-efficiency silicon solar cells during the period May 1989 to August 1990. First, considerable effort was devoted toward developing a ray-tracing program for the photovoltaic community to quantify and optimize surface texturing for solar cells. Second, attempts were made to develop a hydrodynamic model for device simulation. Such a model is somewhat slower than drift-diffusion type models like PC-1D, but it can account for more physical phenomena in the device, such as hot carrier effects, temperature gradients, thermal diffusion, and lattice heat flow. In addition, Fermi-Dirac statistics have been incorporated into the model to deal with heavy doping effects more accurately. Third and final component of the research includes development of silicon cell fabrication capabilities and fabrication of high-efficiency silicon cells. 84 refs., 46 figs., 10 tabs.

  11. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In Situ X-Ray Scattering Helps Optimize Printed Solar Cells Print Plastic solar cells that can be printed on flexible sheets with an ink-like solution show a lot of potential as a...

  12. Award-Winning Etching Process Cuts Solar Cell Costs (Revised) (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

    The NREL "black silicon" nanocatalytic wet-chemical etch is an inexpensive, one-step method to minimize reflections from crystalline silicon solar cells. The technology enables high-efficiency solar cells without the use of expensive antireflection coatings.

  13. Enhanced regeneration of degraded polymer solar cells by thermal annealing

    SciTech Connect (OSTI)

    Kumar, Pankaj; Bilen, Chhinder; Zhou, Xiaojing; Belcher, Warwick J.; Dastoor, Paul C.; Feron, Krishna

    2014-05-12

    The degradation and thermal regeneration of poly(3-hexylethiophene) (P3HT):[6,6]-phenyl-C{sub 61}-butyric acid methyl ester (PCBM) and P3HT:indene-C{sub 60} bisadduct (ICBA) polymer solar cells, with Ca/Al and Ca/Ag cathodes and indium tin oxide/poly(ethylene-dioxythiophene):polystyrene sulfonate anode have been investigated. Degradation occurs via a combination of three primary pathways: (1) cathodic oxidation, (2) active layer phase segregation, and (3) anodic diffusion. Fully degraded devices were subjected to thermal annealing under inert atmosphere. Degraded solar cells possessing Ca/Ag electrodes were observed to regenerate their performance, whereas solar cells having Ca/Al electrodes exhibited no significant regeneration of device characteristics after thermal annealing. Moreover, the solar cells with a P3HT:ICBA active layer exhibited enhanced regeneration compared to P3HT:PCBM active layer devices as a result of reduced changes to the active layer morphology. Devices combining a Ca/Ag cathode and P3HT:ICBA active layer demonstrated ∌50% performance restoration over several degradation/regeneration cycles.

  14. Amorphous silicon solar cells techniques for reactive conditions

    SciTech Connect (OSTI)

    Shimizu, Satoshi; Okawa, Kojiro; Kamiya, Toshio; Fortmann, C.M.; Shimizu, Isamu

    1999-07-01

    The preparation of amorphous silicon films and solar cells using SiH{sub 2}Cl{sub 2} source gas and electron cyclotron resonance assisted chemical vapor deposition (ECR-CVD) was investigated. By using buffer layers to protect previously deposited layers improved a-Si:H(Cl) solar cells were prepared and studied. The high quality a-Si:H(Cl) films used in this study exhibited low defect densities ({approximately}10{sup 15} cm{sup {minus}3}) and high stability under illumination even when the deposition rate was increased to {approximately} 15A/s. The solar cells were deposited in the n-i-p sequence. These solar cells achieved V{sub oc} values of {approximately}0.89V and {approximately}3.9% efficiency on Ga doped ZnO (GZO) coated specular substrate. The a-Si:H(Cl) electron and hole {mu}{tau} products were {approximately}10{sup {minus}8} cm{sup 2}/V.

  15. NREL Success Stories - Quest for Inexpensive Silicon Solar Cells

    ScienceCinema (OSTI)

    Branz, Howard

    2013-05-29

    Scientists at the National Renewable Energy Laboratory (NREL) share their story about a successful partnership with Oak Ridge National Laboratory and the Ampulse Corporation and how support from the US Department of Energy's Technology Commercialization & Deployment Fund has helped it and their silicon solar cell research thrive.

  16. Optical system for determining physical characteristics of a solar cell

    DOE Patents [OSTI]

    Sopori, Bhushan L. (Denver, CO)

    2001-01-01

    The invention provides an improved optical system for determining the physical characteristics of a solar cell. The system comprises a lamp means for projecting light in a wide solid-angle onto the surface of the cell; a chamber for receiving the light through an entrance port, the chamber having an interior light absorbing spherical surface, an exit port for receiving a beam of light reflected substantially normal to the cell, a cell support, and an lower aperture for releasing light into a light absorbing baffle; a means for dispersing the reflection into monochromatic components; a means for detecting an intensity of the components; and a means for reporting the determination.

  17. New World Record Achieved in Solar Cell Technology | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    World Record Achieved in Solar Cell Technology New World Record Achieved in Solar Cell Technology December 5, 2006 - 9:34am Addthis New Solar Cell Breaks the "40 Percent Efficient" Sunlight-to-Electricity Barrier WASHINGTON, DC - U.S. Department of Energy (DOE) Assistant Secretary for Energy Efficiency and Renewable Energy Alexander Karsner today announced that with DOE funding, a concentrator solar cell produced by Boeing-Spectrolab has recently achieved a world-record conversion

  18. High throughput parallel backside contacting and periodic texturing for high-efficiency solar cells

    DOE Patents [OSTI]

    Daniel, Claus; Blue, Craig A.; Ott, Ronald D.

    2014-08-19

    Disclosed are configurations of long-range ordered features of solar cell materials, and methods for forming same. Some features include electrical access openings through a backing layer to a photovoltaic material in the solar cell. Some features include textured features disposed adjacent a surface of a solar cell material. Typically the long-range ordered features are formed by ablating the solar cell material with a laser interference pattern from at least two laser beams.

  19. Polycrystalline Thin-Film Multijunction Solar Cells

    SciTech Connect (OSTI)

    Noufi, R.; Wu, X.; Abu-Shama, J.; Ramanathan, K; Dhere, R.; Zhou, J.; Coutts, T.; Contreras, M.; Gessert, T.; Ward, J. S.

    2005-11-01

    We present a digest of our research on the thin-film material components that comprise the top and bottom cells of three different material systems and the tandem devices constructed from them.

  20. Solar Cells from Earth-Abundant Semiconductors with Plasmon-Enhanced Light Absorption

    SciTech Connect (OSTI)

    Atwater, Harry

    2012-04-30

    Progress is reported in these areas: Plasmonic Light Trapping in Thin Film a-Si Solar Cells; Plasmonic Light Trapping in Thin InGaN Quantum Well Solar Cells; and Earth Abundant Cu{sub 2}O and Zn{sub 3}P{sub 2} Solar Cells.

  1. EERE Success Story-California: TetraCell Silicon Solar Cell Improves...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    This innovative PV technology reduces costs with a simplified process that replaces silver-a high-cost commodity used in traditional screen printed solar cells-with copper, which ...

  2. Improved Electrodes and Electrolytes for Dye-Based Solar Cells

    SciTech Connect (OSTI)

    Harry R. Allcock; Thomas E. Mallouk; Mark W. Horn

    2011-10-26

    The most important factor in limiting the stability of dye-sensitized solar cells is the use of volatile liquid solvents in the electrolytes, which causes leakage during extended operation especially at elevated temperatures. This, together with the necessary complex sealing of the cells, seriously hampers the industrial-scale manufacturing and commercialization feasibilities of DSSCs. The objective of this program was to bring about a significant improvement in the performance and longevity of dye-based solar cells leading to commercialization. This had been studied in two ways first through development of low volatility solid, gel or liquid electrolytes, second through design and fabrication of TiO2 sculptured thin film electrodes.

  3. Flexible Thin-Film Silicon Solar Cells

    SciTech Connect (OSTI)

    Vijh, Aarohi; Cao, Simon; Mohring, Brad

    2014-01-11

    High fuel costs, environmental concerns and issues of national energy security have brought increasing attention to a distributed generation program for electricity based on solar technology. Rooftop photovoltaic (PV) systems provide distributed generation since the power is consumed at the point of production, thus eliminating the need for costly additional transmission lines. However, most current photovoltaic modules are heavy and require a significant amount of labor and accessory hardware such as mounting frames for installation on rooftops. This makes rooftop systems impractical or cost prohibitive in many instances. Under this project, Xunlight has advanced its manufacturing process for the production of lightweight, flexible thin-film silicon based photovoltaic modules, and has enhanced the reliability and performance of Xunlight’s products. These modules are easily unrolled and adhered directly to standard commercial roofs without mounting structures or integrated directly into roofing membrane materials for the lowest possible installation costs on the market. Importantly, Xunlight has now established strategic alliances with roofing material manufacturers and other OEMs for the development of building integrated photovoltaic roofing and other PV-enabled products, and has deployed its products in a number of commercial installations with these business partners.

  4. New Advances in Optical Imaging of Live Cells and Organisms

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Advances in Optical Imaging of Live Cells and Organisms New Advances in Optical Imaging of Live Cells and Organisms Print http://csh-asia.com/13image.html August 20-23, 2913; Suzhou, China

  5. New Advances in Optical Imaging of Live Cells and Organisms

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in Optical Imaging of Live Cells and Organisms New Advances in Optical Imaging of Live Cells and Organisms Print http:csh-asia.com13image.html August 20-23, 2913; Suzhou, China...

  6. High-performance ternary blend polymer solar cells involving both energy transfer and hole relay processes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lu, Luyao; Chen, Wei; Xu, Tao; Yu, Luping

    2015-06-04

    The integration of multiple materials with complementary absorptions into a single junction device is regarded as an efficient way to enhance the power conversion efficiency (PCE) of organic solar cells (OSCs). However, because of increased complexity with one more component, only limited high-performance ternary systems have been demonstrated previously. Here we report an efficient ternary blend OSC with a PCE of 9.2%. We show that the third component can reduce surface trap densities in the ternary blend. Detailed studies unravel that the improved performance results from synergistic effects of enlarged open circuit voltage, suppressed trap-assisted recombination, enhanced light absorption, increasedmore » hole extraction, efficient energy transfer and better morphology. The working mechanism and high device performance demonstrate new insights and design guidelines for high-performance ternary blend solar cells and suggest that ternary structure is a promising platform to boost the efficiency of OSCs.« less

  7. High-performance ternary blend polymer solar cells involving both energy transfer and hole relay processes

    SciTech Connect (OSTI)

    Lu, Luyao; Chen, Wei; Xu, Tao; Yu, Luping

    2015-06-04

    The integration of multiple materials with complementary absorptions into a single junction device is regarded as an efficient way to enhance the power conversion efficiency (PCE) of organic solar cells (OSCs). However, because of increased complexity with one more component, only limited high-performance ternary systems have been demonstrated previously. Here we report an efficient ternary blend OSC with a PCE of 9.2%. We show that the third component can reduce surface trap densities in the ternary blend. Detailed studies unravel that the improved performance results from synergistic effects of enlarged open circuit voltage, suppressed trap-assisted recombination, enhanced light absorption, increased hole extraction, efficient energy transfer and better morphology. The working mechanism and high device performance demonstrate new insights and design guidelines for high-performance ternary blend solar cells and suggest that ternary structure is a promising platform to boost the efficiency of OSCs.

  8. Solar cells with low cost substrates and process of making same

    DOE Patents [OSTI]

    Mitchell, Kim W. (Indian Hills, CO)

    1984-01-01

    A solar cell having a substrate and an intermediate recrystallized film and a semiconductor material capable of absorbing light with the substrate being selected from one of a synthetic organic resin, graphite, glass and a crystalline material having a grain size less than about 1 micron.sup.2. The intermediate recrystallized film has a grain size in the range of from about 10 microns.sup.2 to about 10,000 microns.sup.2 and a lattice mismatch with the semiconductor material not greater than about 4%. The semiconductor material has a grain size not less than about 10 microns.sup.2. An anti-reflective layer and electrical contact means are provided. Also disclosed is a subcombination of substrate, intermediate recrystallized film and semiconductor material. Also, methods of formulating the solar cell and subcombination are disclosed.

  9. Method for cleaning a solar cell surface opening made with a solar etch paste

    DOE Patents [OSTI]

    Rohatgi, Ajeet; Meemongkolkiat, Vichai

    2010-06-22

    A thin silicon solar cell having a back dielectric passivation and rear contact with local back surface field is described. Specifically, the solar cell may be fabricated from a crystalline silicon wafer having a thickness from 50 to 500 micrometers. A barrier layer and a dielectric layer are applied at least to the back surface of the silicon wafer to protect the silicon wafer from deformation when the rear contact is formed. At least one opening is made to the dielectric layer. An aluminum contact that provides a back surface field is formed in the opening and on the dielectric layer. The aluminum contact may be applied by screen printing an aluminum paste having from one to 12 atomic percent silicon and then applying a heat treatment at 750 degrees Celsius.

  10. Student Winners Announced in Solar and Hydrogen Fuel Cell Car Races - News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Releases | NREL Student Winners Announced in Solar and Hydrogen Fuel Cell Car Races May 21, 2011 Sixty-five teams from 24 Colorado schools participated in today's Junior Solar Sprint and Hydrogen Fuel Cell car competitions hosted by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL). The student teams raced solar or hydrogen fuel cell powered vehicles they designed and built themselves. Trophies for the fastest solar powered model cars were given to Colorado students

  11. ANSER Center Chemists Design a First-of-its-Kind Solar Cell Experiment for

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    General Chemistry Students | ANSER Center | Argonne-Northwestern National Laboratory ANSER Center Chemists Design a First-of-its-Kind Solar Cell Experiment for General Chemistry Students Home > News & Events > ANSER Chemists Design First Solar Cell Lab for Gen Chem Students ANSER Center Chemists Design First Solar Cell Lab for General Chemistry Students by Monika Wnuk Northwestern scientists, Sameer Patwardhan and Duyen Cao, from the Argonne-Northwestern Solar Energy Research

  12. GaNPAs Solar Cells that Can Be Lattice-Matched to Silicon

    SciTech Connect (OSTI)

    Geisz, J. F.; Friedman, D. J.; McMahon, W. E.; Ptak, A. J.; Kibbler, A. E.; Olson, J. M.; Kurtz, S.; Kramer, C.; Young, M.; Duda, A.; Reedy, R. C.; Keyes, B. M.; Dippo, P.; Metzger, W. K.

    2003-05-01

    III-V semiconductors grown on silicon substrates are very attractive for lower-cost, high-efficiency multijunction solar cells, but lattice-mismatched alloys that result in high dislocation densities have been unable to achieve satisfactory performance. GaNxP1-x-yAsy is a direct-gap III-V alloy that can be grown lattice-matched to Si when y= 4.7x - 0.1. We have proposed the use of lattice-matched GaNPAs on silicon for high-efficiency multijunction solar cells. We have grown GaNxP1-x-yAsy on GaP (with a similar lattice constant to silicon) by metal-organic chemical vapor phase epitaxy with direct bandgaps in the range of 1.5 to 2.0 eV. We have demonstrated the performance of single-junction GaNxP1-x-yAsy solar cells grown on GaP substrates and shown improvements in material quality by reducing carbon and hydrogen impurities through optimization of growth conditions. We have achieved quantum efficiencies (QE) in these cells as high as 60% and PL lifetimes as high as 3.0 ns.

  13. Generalized Optoelectronic Model of Series-Connected Multijunction Solar Cells

    SciTech Connect (OSTI)

    Geisz, John F.; Steiner, Myles A.; Garcia, Ivan; France, Ryan M.; McMahon, William E.; Osterwald, Carl R.; Friedman, Daniel J.

    2015-11-01

    The emission of light from each junction in a series-connected multijunction solar cell, we found, both complicates and elucidates the understanding of its performance under arbitrary conditions. Bringing together many recent advances in this understanding, we present a general 1-D model to describe luminescent coupling that arises from both voltage-driven electroluminescence and voltage-independent photoluminescence in nonideal junctions that include effects such as Sah-Noyce-Shockley (SNS) recombination with n ≠ 2, Auger recombination, shunt resistance, reverse-bias breakdown, series resistance, and significant dark area losses. The individual junction voltages and currents are experimentally determined from measured optical and electrical inputs and outputs of the device within the context of the model to fit parameters that describe the devices performance under arbitrary input conditions. Furthermore, our techniques to experimentally fit the model are demonstrated for a four-junction inverted metamorphic solar cell, and the predictions of the model are compared with concentrator flash measurements.

  14. Design for the fabrication of high efficiency solar cells

    DOE Patents [OSTI]

    Simmons, Joseph H.

    1998-01-01

    A method and apparatus for a photo-active region for generation of free carriers when a first surface is exposed to optical radiation. The photo-active region includes a conducting transparent matrix and clusters of semiconductor materials embedded within the conducting transparent matrix. The clusters are arranged in the matrix material so as to define at least a first distribution of cluster sizes ranging from those with the highest bandgap energy near a light incident surface of the photo-active region to those with the smallest bandgap energy near an opposite second surface of the photo-active region. Also disclosed is a method and apparatus for a solar cell. The solar cell includes a photo-active region containing a plurality of semiconductor clusters of varying sizes as described.

  15. Towards understanding junction degradation in cadmium telluride solar cells

    SciTech Connect (OSTI)

    Nardone, Marco

    2014-06-21

    A degradation mechanism in cadmium telluride (CdTe/CdS) solar cells is investigated using time-dependent numerical modeling to simulate various temperature, bias, and illumination stress conditions. The physical mechanism is based on defect generation rates that are proportional to nonequilibrium charge carrier concentrations. It is found that a commonly observed degradation mode for CdTe/CdS solar cells can be reproduced only if defects are allowed to form in a narrow region of the absorber layer close to the CdTe/CdS junction. A key aspect of this junction degradation is that both mid-gap donor and shallow acceptor-type defects must be generated simultaneously in response to photo-excitation or applied bias. The numerical approach employed here can be extended to study other mechanisms for any photovoltaic technology.

  16. Amorphous silicon cell array powered solar tracking apparatus

    DOE Patents [OSTI]

    Hanak, Joseph J.

    1985-01-01

    An array of an even number of amorphous silicon solar cells are serially connected between first and second terminals of opposite polarity. The terminals are connected to one input terminal of a DC motor whose other input terminal is connected to the mid-cell of the serial array. Vane elements are adjacent the end cells to selectively shadow one or the other of the end cells when the array is oriented from a desired attitude relative to the sun. The shadowing of one cell of a group of cells on one side of the mid-cell reduces the power of that group substantially so that full power from the group of cells on the other side of the mid-cell drives the motor to reorient the array to the desired attitude. The cell groups each have a full power output at the power rating of the motor. When the array is at the desired attitude the power output of the two groups of cells balances due to their opposite polarity so that the motor remains unpowered.

  17. $6 Million in Awards to Advance Solar Cell Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    $6 Million in Awards to Advance Solar Cell Research For more information contact: George Douglas, 303-275-4096 email: George Douglas Golden, Colo., Apr. 13, 2001 - The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) today announced $6 million in awards to 11 universities and five companies for high tech research into non-conventional, photovoltaic technologies for creating electricity from sunlight. Each award has the potential to create a breakthrough that could

  18. Highly Efficient Multigap Solar Cell Materials - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Highly Efficient Multigap Solar Cell Materials Lawrence Berkeley National Laboratory Contact LBL About This Technology Publications: PDF Document Publication Yu, K. M., Walukeiwicz, W., Wu J., Shan, W., Beeman, J. W., Scarpulla, M. A., Dubon, O. D., Becla, P. "Diluted II-VI Oxide Semiconductors with Multiple Band Gaps," Physical Review Letters, Vo. 91, No. 24, Dec. 12, 2003. (178 KB) Technology Marketing Summary Scientists at Berkeley Lab have invented multiband gap semiconducting

  19. Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells

    SciTech Connect (OSTI)

    Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

    2011-01-01

    We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n{sup ++} Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

  20. Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells: Preprint

    SciTech Connect (OSTI)

    Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

    2011-07-01

    We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n++ Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

  1. Encapsulant Material For Solar Cell Module And Laminated Glass Applications

    DOE Patents [OSTI]

    Hanoka, Jack I. (Brookline, MA); Klemchuk, Peter P. (Watertown, CT)

    2001-02-13

    An encapsulant material includes a layer of metallocene polyethylene disposed between two layers of an acid copolymer of polyethylene. More specifically, the layer of metallocene polyethylene is disposed adjacent a rear surface of the first layer of the acid copolymer of polyethylene, and a second layer of the acid copolymer of polyethlene is disposed adjacent a rear surface of the layer of metallocene polyethylene. The encapsulant material can be used in solar cell module and laminated glass applications.

  2. Encapsulant Material For Solar Cell Module And Laminated Glass Applications

    DOE Patents [OSTI]

    Hanoka, Jack I. (Brookline, MA)

    2000-09-05

    An encapsulant material includes a layer of metallocene polyethylene disposed between two layers of ionomer. More specifically, the layer of metallocene polyethylene is disposed adjacent a rear surface of the first ionomer layer, and a second layer of ionomer is disposed adjacent a rear surface of the layer of metallocene polyethylene. The encapsulant material can be used in solar cell module and laminated glass applications.

  3. Alan J. Heeger, Conductive Polymers, and Plastic Solar Cells

    Office of Scientific and Technical Information (OSTI)

    Alan J. Heeger, Conductive Polymers, and Plastic Solar Cells Resources with Additional Information * Patents * Videos After receiving 'his physics Ph.D. at the University of California at Berkeley in 1961, [Alan J.] Heeger would spend the next 20 years teaching the subject at the University of Pennsylvania - while also designing and then launching one of the nation's premiere scientific think tanks: the Laboratory for Research on the Structure of Matter. Alan J. Heeger Courtesy of Randy Lamb,

  4. Photo of the Week: Butterflies, Crystal Nanostructures and Solar Cell

    Broader source: Energy.gov (indexed) [DOE]

    Research | Department of Energy What do butterflies and solar cell research have in common? Both have been developing tiny crystals that selectively reflect colors. Over millions of years of evolution, butterfly wings have developed the tiny crystal nanostructures that give butterflies their vivid colors. At Argonne National Laboratory, scientists are working to manufacture these crystals, which could one day be used to create "greener" and more efficient paints, fiber optics and

  5. Radial electron collection in dye-sensitized solar cells.

    SciTech Connect (OSTI)

    Martinson, A. B. B.; Elam, J. W.; Liu, J.; Pellin, M. J.; Marks, T. J.; Hupp, J. T.; Materials Science Division; Northwestern Univ.

    2008-01-01

    We introduce a new photoelectrode architecture consisting of concentric conducting and semiconducting nanotubes for use in dye-sensitized solar cells (DSSCs). Atomic layer deposition is employed to grow indium tin oxide (ITO) within a porous template and subsequently coat the high area photoelectrode with amorphous TiO2. Compared with control devices lacking a current collector within the pores, the new photoelectrode geometry exhibits dramatically higher current densities, an effect attributed to the radial collection of electrons.

  6. Solar cell comprising a plasmonic back reflector and method therefor

    DOE Patents [OSTI]

    Ding, I-Kang; Zhu, Jia; Cui, Yi; McGehee, Michael David

    2014-11-25

    A method for forming a solar cell having a plasmonic back reflector is disclosed. The method includes the formation of a nanoimprinted surface on which a metal electrode is conformally disposed. The surface structure of the nanoimprinted surface gives rise to a two-dimensional pattern of nanometer-scale features in the metal electrode enabling these features to collectively form the plasmonic back reflector.

  7. NREL: News - Scientific American' Recognizes Solar Cell Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientific American' Recognizes Solar Cell Research Monday November 11, 2002 Magazine Names NREL to its First "Scientific American 50" List Golden, CO. - The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) has been named by Scientific American magazine as one of the Scientific American 50 - the noted magazine's first list recognizing annual contributions to science and technology that provide a vision of a better future. Announced today, the Scientific American

  8. The influence of molecular orientation on organic bulk heterojunction...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on organic bulk heterojunction solar cells The influence of molecular orientation on organic bulk heterojunction solar cells Print Monday, 28 April 2014 09:03 Work done on ALS...

  9. RECOVERY ACT: MULTIMODAL IMAGING FOR SOLAR CELL MICROCRACK DETECTION

    SciTech Connect (OSTI)

    Janice Hudgings; Lawrence Domash

    2012-02-08

    Undetected microcracks in solar cells are a principal cause of failure in service due to subsequent weather exposure, mechanical flexing or diurnal temperature cycles. Existing methods have not been able to detect cracks early enough in the production cycle to prevent inadvertent shipment to customers. This program, sponsored under the DOE Photovoltaic Supply Chain and Cross-Cutting Technologies program, studied the feasibility of quantifying surface micro-discontinuities by use of a novel technique, thermoreflectance imaging, to detect surface temperature gradients with very high spatial resolution, in combination with a suite of conventional imaging methods such as electroluminescence. The project carried out laboratory tests together with computational image analyses using sample solar cells with known defects supplied by industry sources or DOE National Labs. Quantitative comparisons between the effectiveness of the new technique and conventional methods were determined in terms of the smallest detectable crack. Also the robustness of the new technique for reliable microcrack detection was determined at various stages of processing such as before and after antireflectance treatments. An overall assessment is that the new technique compares favorably with existing methods such as lock-in thermography or ultrasonics. The project was 100% completed in Sept, 2010. A detailed report of key findings from this program was published as: Q.Zhou, X.Hu, K.Al-Hemyari, K.McCarthy, L.Domash and J.Hudgings, High spatial resolution characterization of silicon solar cells using thermoreflectance imaging, J. Appl. Phys, 110, 053108 (2011).

  10. Thin film cadmium telluride and zinc phosphide solar cells

    SciTech Connect (OSTI)

    Chu, T.

    1984-10-01

    This report describes research performed from June 1982 to October 1983 on the deposition of cadmium telluride films by direct combination of the cadmium and tellurium vapor on foreign substrates. Nearly stoichiometric p-type cadmium telluride films and arsenic-doped p-type films have been prepared reproducibly. Major efforts were directed to the deposition and characterization of heterojunction window materials, indium tin oxide, fluorine-doped tin oxide, cadmium oxide, and zinc oxide. A number of heterojunction solar cells were prepared, and the best thin-film ITO/CdTe solar cells had an AMl efficiency of about 7.2%. Zinc phosphide films were deposited on W/steel substrates by the reaction of zinc and phosphine in a hydrogen flow. Films without intentional doping had an electrical resistivity on the order of 10/sup 6/ ohm-cm, and this resistivity may be reduced to about 5 x 10/sup 4/ ohm-cm by adding hydrogen chloride or hydrogen bromide to the reaction mixture. Lower resistivity films were deposited by adding a controlled amount of silver nitrate solution on to the substrate surface. Major efforts were directed to the deposition of low-resistivity zinc selenide in order to prepare ZnSe/An/sub 3/P/sub 2/ heterojunction thin-film solar cells. However, zinc selenide films deposited by vacuum evaporation and chemical vapor deposition techniques were all of high resistivity.

  11. California: TetraCell Silicon Solar Cell Improves Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    TetraSun, in partnership with the National Renewable Energy Laboratory, developed a novel crystalline silicon photovoltaic (PV) cell architecture and manufacturing process that ...

  12. Discovering an Active Subspace in a Single-Diode Solar Cell Model...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Discovering an Active Subspace in a Single-Diode Solar Cell Model Citation Details In-Document Search Title: Discovering an Active Subspace in a Single-Diode Solar ...

  13. On-line, Continuous Monitoring in Solar Cell and Fuel Cell Manufacturing

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using Spectral Reflectance Imaging - Energy Innovation Portal 40204383 Site Map Printable Version Share this resource About Search Categories (15) Advanced Materials Biomass and Biofuels Building Energy Efficiency Electricity Transmission Energy Analysis Energy Storage Geothermal Hydrogen and Fuel Cell Hydropower, Wave and Tidal Industrial Technologies Solar Photovoltaic Solar Thermal Startup America Vehicles and Fuels Wind Energy Partners (27) Visual Patent Search Success Stories Return to

  14. On-line, continuous monitoring in solar cell and fuel cell manufacturing

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    using spectral reflectance imaging - Energy Innovation Portal 234,843 Site Map Printable Version Share this resource About Search Categories (15) Advanced Materials Biomass and Biofuels Building Energy Efficiency Electricity Transmission Energy Analysis Energy Storage Geothermal Hydrogen and Fuel Cell Hydropower, Wave and Tidal Industrial Technologies Solar Photovoltaic Solar Thermal Startup America Vehicles and Fuels Wind Energy Partners (27) Visual Patent Search Success Stories Find More

  15. High Rate Laser Pitting Technique for Solar Cell Texturing

    SciTech Connect (OSTI)

    Hans J. Herfurth; Henrikki Pantsar

    2013-01-10

    High rate laser pitting technique for solar cell texturing Efficiency of crystalline silicon solar cells can be improved by creating a texture on the surface to increase optical absorption. Different techniques have been developed for texturing, with the current state-of-the-art (SOA) being wet chemical etching. The process has poor optical performance, produces surfaces that are difficult to passivate or contact and is relatively expensive due to the use of hazardous chemicals. This project shall develop an alternative process for texturing mc-Si using laser micromachining. It will have the following features compared to the current SOA texturing process: -Superior optical surfaces for reduced front-surface reflection and enhanced optical absorption in thin mc-Si substrates -Improved surface passivation -More easily integrated into advanced back-contact cell concepts -Reduced use of hazardous chemicals and waste treatment -Similar or lower cost The process is based on laser pitting. The objective is to develop and demonstrate a high rate laser pitting process which will exceed the rate of former laser texturing processes by a factor of ten. The laser and scanning technologies will be demonstrated on a laboratory scale, but will use inherently technologies that can easily be scaled to production rates. The drastic increase in process velocity is required for the process to be implemented as an in-line process in PV manufacturing. The project includes laser process development, development of advanced optical systems for beam manipulation and cell reflectivity and efficiency testing. An improvement of over 0.5% absolute in efficiency is anticipated after laser-based texturing. The surface textures will be characterized optically, and solar cells will be fabricated with the new laser texturing to ensure that the new process is compatible with high-efficiency cell processing. The result will be demonstration of a prototype process that is suitable for scale-up to a production tool and process. The developed technique will have an reducing impact on product pricing. As efficiency has a substantial impact on the economics of solar cell production due to the high material cost content; in essence, improved efficiency through cost-effective texturing reduces the material cost component since the product is priced in terms of $/W. The project is a collaboration between Fraunhofer USA, Inc. and a c-Si PV manufacturer.

  16. NREL Demonstrates 45.7% Efficiency for Concentrator Solar Cell - News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Releases | NREL NREL Demonstrates 45.7% Efficiency for Concentrator Solar Cell New design for ultra-efficient III-V multijunction cell pushes the limits of solar conversion December 16, 2014 The Energy Department's National Renewable Energy Laboratory has announced the demonstration of a 45.7 percent conversion efficiency for a four-junction solar cell at 234 suns concentration. This achievement represents one of the highest photovoltaic research cell efficiencies achieved across all types

  17. NREL Produces Highly Efficient, Wide-Bandgap, Thin-Film Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-09-01

    Researchers at the National Renewable Energy Laboratory (NREL) are finding new ways to manufacture thin-film solar cells made from copper, indium, gallium, and selenium - called CIGS cells - that are different than conventional CIGS solar cells. Their use of high-temperature glass, designed by SCHOTT AG, allows higher fabrication temperatures, opening the door to new CIGS solar cells employing light-absorbing materials with wide 'bandgaps.'

  18. Fuel Cell Technologies Office Organization Chart and Contacts | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Cell Technologies Office Organization Chart and Contacts Fuel Cell Technologies Office Organization Chart and Contacts Fuel Cell Technologies Office Organization Chart and Contacts Contact Information U.S. Department of Energy - Fuel Cell Technologies Office General Contact Information 202-586-3388 fuelcells@ee.doe.gov Office Contacts Director Sunita Satyapal 202-586-2336 Sunita.Satyapal@ee.doe.gov Operations Supervisor and Technology Acceleration Program Manager Rick Farmer

  19. Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells

    SciTech Connect (OSTI)

    Chu, T.L. )

    1992-04-01

    This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44 {mu}m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD{sub 1-x}Zn{sub 1-x}Te, and Hg{sub 1-x}Zn{sub x}Te solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400{degrees}C using TEGa and AsH{sub 3} as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd{sub 1- x}Zn{sub x}Te, and Hg{sub 1-x}Zn{sub x}Te were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized. 67 refs.

  20. Copper migration in CdTe heterojunction solar cells

    SciTech Connect (OSTI)

    Chou, H.C.; Rohatgi, A.; Jokerst, N.M.; Thomas, E.W.; Kamra, S.

    1996-07-01

    CdTe solar cells were fabricated by depositing a Au/Cu contact with Cu thickness in the range of 50 to 150A on polycrystalline CdTe/CdS/SnO{sub 2} glass structures. The increase in Cu thickness improves ohmic contact and reduces series resistance (R{sub s}), but the excess Cu tends to diffuse into CdTe and lower shunt resistance (R{sub sh}) and cell performance. Light I-V and secondary ion mass spectroscopy (SIMS) measurements were performed to understand the correlations between the Cu contact thickness, the extent of Cu incorporation in the CdTe cells, and its impact on the cell performance. The CdTe/CdS/SnO{sub 2} glass, CdTe/CdS/GaAs, and CdTe/GaAs structures were prepared in an attempt to achieve CdTe films with different degrees of crystallinity and grain size. A large grain polycrystalline CdTe thin film solar cell was obtained for the first time by selective etching the GaAs substrate coupled with the film transfer onto a glass substrate. SIMS measurement showed that poor crystallinity and smaller grain size of the CdTe film promotes Cu diffusion and decreases the cell performance. Therefore, grain boundaries are the main conduits for Cu migration and larger CdTe grain size or alternate method of contact formation can mitigate the adverse effect of Cu and improve the cell performance. 15 refs., 1 fig.,6 tabs.

  1. Record Makes Thin-Film Solar Cell Competitive with Silicon Efficiency -

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    News Releases | NREL Record Makes Thin-Film Solar Cell Competitive with Silicon Efficiency March 24, 2008 Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory have moved closer to creating a thin-film solar cell that can compete with the efficiency of the more common silicon-based solar cell. The copper indium gallium diselenide (CIGS) thin-film solar cell recently reached 19.9 percent efficiency, setting a new world record for this type of cell.

  2. PV Optics: A Software Package for Solar Cells and Module Design

    SciTech Connect (OSTI)

    Sopori, B.

    2007-01-01

    PV Optics is a user-friendly software package developed to design and analyze solar cells and modules. It is applicable to a variety of optical structures, including thin and thick cells with light-trapping structures and metal optics. Using a combination of wave and ray optics to include effects of coherence and interference, it can be used to design single-junction and multijunction solar cells and modules. This paper describes some basic applications of PV Optics for crystalline and amorphous Si solar cell design. We present examples to examine the effects on solar cell performance of wafer thickness, antireflection coating thickness, texture height, and metal loss.

  3. Efficient methylammonium lead iodide perovskite solar cells with active layers from 300 to 900 nm

    SciTech Connect (OSTI)

    Momblona, C.; Malinkiewicz, O.; Soriano, A.; Gil-Escrig, L.; Bandiello, E.; Scheepers, M.; Bolink, H. J.; Edri, E.

    2014-08-01

    Efficient methylammonium lead iodide perovskite-based solar cells have been prepared in which the perovskite layer is sandwiched in between two organic charge transporting layers that block holes and electrons, respectively. This configuration leads to stable and reproducible devices that do not suffer from strong hysteresis effects and when optimized lead to efficiencies close to 15%. The perovskite layer is formed by using a dual-source thermal evaporation method, whereas the organic layers are processed from solution. The dual-source thermal evaporation method leads to smooth films and allows for high precision thickness variations. Devices were prepared with perovskite layer thicknesses ranging from 160 to 900 nm. The short-circuit current observed for these devices increased with increasing perovskite layer thickness. The main parameter that decreases with increasing perovskite layer thickness is the fill factor and as a result optimum device performance is obtained for perovskite layer thickness around 300 nm. However, here we demonstrate that with a slightly oxidized electron blocking layer the fill factor for the solar cells with a perovskite layer thickness of 900 nm increases to the same values as for the devices with thin perovskite layers. As a result the power conversion efficiencies for the cells with 300 and 900 nm are very similar, 12.7% and 12%, respectively.

  4. Methods for fabricating thin film III-V compound solar cell

    DOE Patents [OSTI]

    Pan, Noren; Hillier, Glen; Vu, Duy Phach; Tatavarti, Rao; Youtsey, Christopher; McCallum, David; Martin, Genevieve

    2011-08-09

    The present invention utilizes epitaxial lift-off in which a sacrificial layer is included in the epitaxial growth between the substrate and a thin film III-V compound solar cell. To provide support for the thin film III-V compound solar cell in absence of the substrate, a backing layer is applied to a surface of the thin film III-V compound solar cell before it is separated from the substrate. To separate the thin film III-V compound solar cell from the substrate, the sacrificial layer is removed as part of the epitaxial lift-off. Once the substrate is separated from the thin film III-V compound solar cell, the substrate may then be reused in the formation of another thin film III-V compound solar cell.

  5. Front contact solar cell with formed electrically conducting layers on the front side and backside

    DOE Patents [OSTI]

    Cousins, Peter John

    2012-06-26

    A bipolar solar cell includes a backside junction formed by a silicon substrate and a first doped layer of a first dopant type on the backside of the solar cell. A second doped layer of a second dopant type makes an electrical connection to the substrate from the front side of the solar cell. A first metal contact of a first electrical polarity electrically connects to the first doped layer on the backside of the solar cell, and a second metal contact of a second electrical polarity electrically connects to the second doped layer on the front side of the solar cell. An external electrical circuit may be electrically connected to the first and second metal contacts to be powered by the solar cell.

  6. Region Solar Inc Solar Inc California Renewable Energy Solar...

    Open Energy Info (EERE)

    Point Drive Fort Collins Colorado Solar Solar cell passive solar architectural glass solar grid tie inverter semiconductor flat panel display data storage http www advanced...

  7. High-Efficiency Solar Cells for Large-Scale Electricity Generation

    SciTech Connect (OSTI)

    Kurtz, S.; Olson, J.; Geisz, J.; Friedman, D.; McMahon, W.; Ptak, A.; Wanlass, M.; Kibbler, A.; Kramer, C.; Bertness, K.; Ward, S.; Duda, A.; Young, M.; Carapella, J.; Steiner, M.

    2008-09-26

    One strategy for helping the solar industry to grow faster is to use very high efficiency cells under concentrating optics. By using lenses or mirrors to concentrate the light, very small solar cells can be used, reducing the amount of semiconductor material and allowing use of higher efficiency cells, which are now >40% efficient.

  8. Polycrystalline MBE-grown GaAs for solar cells

    SciTech Connect (OSTI)

    Friedman, D.J.; Kurtz, S.R.; Kibbler, A.E.; Al-Jassim, M.; Jones, K.; Keyes, B.; Matson, R.

    1997-02-01

    This paper will discuss initial studies of thin-film GaAs grown by molecular-beam epitaxy for use in developing a thin-film GaAs solar cell. Photocurrent and photoluminescence intensity are related to the material morphology as a function of growth conditions. Growth temperature and V/III ratio have a dramatic effect on the photocurrent. However, it seems likely that even after optimizing such growth parameters, it will be necessary to provide substrates that can provide templates to enhance grain size from the start of thin-film growth. {copyright} {ital 1997 American Institute of Physics.}

  9. Polycrystalline MBE-grown GaAs for solar cells

    SciTech Connect (OSTI)

    Friedman, D. J.; Kurtz, Sarah R.; Kibbler, A. E.; Al-Jassim, M.; Jones, K.; Keyes, B.; Matson, R.

    1997-02-15

    This paper will discuss initial studies of thin-film GaAs grown by molecular-beam epitaxy for use in developing a thin-film GaAs solar cell. Photocurrent and photoluminescence intensity are related to the material morphology as a function of growth conditions. Growth temperature and V/III ratio have a dramatic effect on the photocurrent. However, it seems likely that even after optimizing such growth parameters, it will be necessary to provide substrates that can provide templates to enhance grain size from the start of thin-film growth.

  10. NREL Designs Promising New Oxides for Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-04-01

    High-efficiency, thin-film solar cells require electrical contacts with high electrical conductivity, and the top contact must also have high optical transparency. This need is currently met by transparent conducting oxides (TCOs), which conduct electricity but are 90% transparent to visible light. Scientists at the National Renewable Energy Laboratory (NREL) have derived three key design principles for selecting promising materials for TCO contacts. NREL's application of these design principles has resulted in a 10,000-fold improvement in conductivity for one TCO material.

  11. Silicon-film{trademark} on ceramic solar cells. Final report

    SciTech Connect (OSTI)

    Hall, R.B.; Bacon, C.; DiReda, V.; Ford, D.H.; Ingram, A.E.; Lampo, S.M.; Rand, J.A.; Ruffins, T.R.; Barnett, A.M.

    1993-02-01

    The Silicon-Film{trademark} design achieves high performance through the use of a thin silicon layer. Optimally designed thin crystalline solar cells (<50 microns thick) have performance advantages over conventional thick devices. The enhancement in performance requires the incorporation of back-surface passivation and light trapping. The high-performance Silicon-Film{trademark} design employs a metallurgical barrier between the low-cost substrate and the thin silicon layer. The properties of the metallurgical barrier must be engineered to implement specific device requirements, such as high back-surface reflectivity. Recent advances in process development are described here.

  12. Ideal solar cell equation in the presence of photon recycling

    SciTech Connect (OSTI)

    Lan, Dongchen Green, Martin A.

    2014-11-07

    Previous derivations of the ideal solar cell equation based on Shockley's p-n junction diode theory implicitly assume negligible effects of photon recycling. This paper derives the equation in the presence of photon recycling that modifies the values of dark saturation and light-generated currents, using an approach applicable to arbitrary three-dimensional geometries with arbitrary doping profile and variable band gap. The work also corrects an error in previous work and proves the validity of the reciprocity theorem for charge collection in such a more general case with the previously neglected junction depletion region included.

  13. Ablation of film stacks in solar cell fabrication processes

    DOE Patents [OSTI]

    Harley, Gabriel; Kim, Taeseok; Cousins, Peter John

    2013-04-02

    A dielectric film stack of a solar cell is ablated using a laser. The dielectric film stack includes a layer that is absorptive in a wavelength of operation of the laser source. The laser source, which fires laser pulses at a pulse repetition rate, is configured to ablate the film stack to expose an underlying layer of material. The laser source may be configured to fire a burst of two laser pulses or a single temporally asymmetric laser pulse within a single pulse repetition to achieve complete ablation in a single step.

  14. Solar cell structure incorporating a novel single crystal silicon material

    DOE Patents [OSTI]

    Pankove, Jacques I. (Princeton, NJ); Wu, Chung P. (Trenton, NJ)

    1983-01-01

    A novel hydrogen rich single crystal silicon material having a band gap energy greater than 1.1 eV can be fabricated by forming an amorphous region of graded crystallinity in a body of single crystalline silicon and thereafter contacting the region with atomic hydrogen followed by pulsed laser annealing at a sufficient power and for a sufficient duration to recrystallize the region into single crystal silicon without out-gassing the hydrogen. The new material can be used to fabricate semiconductor devices such as single crystal silicon solar cells with surface window regions having a greater band gap energy than that of single crystal silicon without hydrogen.

  15. Award-Winning Etching Process Cuts Solar Cell Costs - Energy Innovation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Portal Award-Winning Etching Process Cuts Solar Cell Costs National Renewable Energy Laboratory Success Story Details Partner Location Agreement Type Publication Date Natcore Technology Inc. New Jersey Other August 1, 2013 Summary Optimizing solar-cell technology can be a complex job, requiring expertise in material science, physics, and optics to convert as much sunlight as possible into electricity. But despite this complexity, a simple fact is key to making a high-performance solar cell:

  16. Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Lower Cost | Department of Energy Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost April 18, 2013 - 12:00am Addthis Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost Partnering with Sunnyvale-based Innovalight, which was acquired by DuPont in July 2011, EERE supported the development of the first commercially available liquid silicon offering a

  17. Characterization and Analysis of CIGS and CdTE Solar Cells: December 2004 - July 2008

    SciTech Connect (OSTI)

    Sites, J. R.

    2009-01-01

    The work reported here embodies a device-physics approach based on careful measurement and interpretation of data from CIGS and CdTe solar cells.

  18. NREL Develops ZnSiP2 for Silicon-Based Tandem Solar Cells (Fact...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    an Earth-abundant chalcopyrite with a silicon layer could significantly boost conversion efficiency above that of single-junction silicon solar cells. A current technological...

  19. High Efficiency CdTe and CIGS Thin Film Solar Cells: Highlights...

    Office of Scientific and Technical Information (OSTI)

    High Efficiency CdTe and CIGS Thin Film Solar Cells: Highlights of the Technologies Challenges Acknowledgement: Work performed at NREL for US DOE under contract No....

  20. Scientists Confirm Robustness of Key Component in Ultra-High-Efficiency Solar Cell (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

    Scientists developed and tested a new, stable 1-eV metamorphic junction for a high efficiency multijunction III-V solar cell for CPV application.

  1. New Selection Metric for Design of Thin-Film Solar Cell Absorber...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    guidance for the experimental synthesis. New Selection Metric for Design of Thin-Film Solar Cell Absorber Materials Research Details * SLME account s for the physics of...

  2. Methods For Improving Polymeric Materials For Use In Solar Cell Applications

    DOE Patents [OSTI]

    Hanoka, Jack I. (Brookline, MA)

    2001-11-20

    A method of manufacturing a solar cell module includes the use of low cost polymeric materials with improved mechanical properties. A transparent encapsulant layer is placed adjacent a rear surface of a front support layer. Interconnected solar cells are positioned adjacent a rear surface of the transparent encapsulant layer to form a solar cell assembly. A backskin layer is placed adjacent a rear surface of the solar cell assembly. At least one of the transparent encapsulant layer and the backskin layer are predisposed to electron beam radiation.

  3. Methods For Improving Polymeric Materials For Use In Solar Cell Applications

    DOE Patents [OSTI]

    Hanoka, Jack I. (Brookline, MA)

    2003-07-01

    A method of manufacturing a solar cell module includes the use of low cost polymeric materials with improved mechanical properties. A transparent encapsulant layer is placed adjacent a rear surface of a front support layer. Interconnected solar cells are positioned adjacent a rear surface of the transparent encapsulant layer to form a solar cell assembly. A backskin layer is placed adjacent a rear surface of the solar cell assembly. At least one of the transparent encapsulant layer and the backskin layer are predisposed to electron beam radiation.

  4. Technique Reveals Critical Physics in Deep Regions of Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-01-01

    NREL's improved time-resolved photoluminescence method measures minority-carrier lifetime deep within photovoltaic samples to help develop more efficient solar cells.

  5. NREL Develops ZnSiP2 for Silicon-Based Tandem Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-08-01

    Combining an Earth-abundant chalcopyrite with a silicon layer could significantly boost conversion efficiency above that of single-junction silicon solar cells.

  6. Getting More Electricity out of Solar Cells | U.S. DOE Office...

    Office of Science (SC) Website

    Getting More Electricity out of Solar Cells Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News EFRC Events DOE ...

  7. There's a Great Future in Plastic Solar Cells | U.S. DOE Office...

    Office of Science (SC) Website

    There's a Great Future in Plastic Solar Cells Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy ...

  8. Future Solar Cells: Thinner, Brighter, and Better | U.S. DOE...

    Office of Science (SC) Website

    Future Solar Cells: Thinner, Brighter, and Better Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic ...

  9. Antireflection Coating Design for Series Interconnected Multi-Junction Solar Cells

    SciTech Connect (OSTI)

    AIKEN,DANIEL J.

    1999-11-29

    AR coating design for multi-junction solar cells can be more challenging than in the single junction case. Reasons for this are discussed. Analytical expressions used to optimize AR coatings for single junction solar cells are extended for use in monolithic, series interconnected multi-junction solar cell AR coating design. The result is an analytical expression which relates the solar cell performance (through J{sub SC}) directly to the AR coating design through the device reflectance. It is also illustrated how AR coating design can be used to provide an additional degree of freedom for current matching multi-junction devices.

  10. New Advances in Optical Imaging of Live Cells and Organisms

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Advances in Optical Imaging of Live Cells and Organisms http://csh-asia.com/13image.html August 20-23, 2913; Suzhou, China

  11. InGaAsN Solar Cells with 1.0eV Bandgap, Lattice Matched to GaAs

    SciTech Connect (OSTI)

    Allerman, A.A.; Banas, J.J.; Gee, J.M.; Hammons, B.E.; Jones, E.D.; Kurtz, S.R.

    1998-11-24

    The design, growth by metal-organic chemical vapor deposition, and processing of an In{sub 0.07}Ga{sub 0.93}As{sub 0.98}N{sub 0.02} solar Al, with 1.0 ev bandgap, lattice matched to GaAs is described. The hole diffusion length in annealed, n-type InGaAsN is 0.6-0.8 pm, and solar cell internal quantum efficiencies > 70% arc obwined. Optical studies indicate that defects or impurities, from InGAsN doping and nitrogen incorporation, limit solar cell performance.

  12. Advanced Nanomaterials for High-Efficiency Solar Cells

    SciTech Connect (OSTI)

    Chen, Junhong

    2013-11-29

    Energy supply has arguably become one of the most important problems facing humankind. The exponential demand for energy is evidenced by dwindling fossil fuel supplies and record-high oil and gas prices due to global population growth and economic development. This energy shortage has significant implications to the future of our society, in addition to the greenhouse gas emission burden due to consumption of fossil fuels. Solar energy seems to be the most viable choice to meet our clean energy demand given its large scale and clean/renewable nature. However, existing methods to convert sun light into electricity are not efficient enough to become a practical alternative to fossil fuels. This DOE project aims to develop advanced hybrid nanomaterials consisting of semiconductor nanoparticles (quantum dots or QDs) supported on graphene for cost-effective solar cells with improved conversion efficiency for harvesting abundant, renewable, clean solar energy to relieve our global energy challenge. Expected outcomes of the project include new methods for low-cost manufacturing of hybrid nanostructures, systematic understanding of their properties that can be tailored for desired applications, and novel photovoltaic cells. Through this project, we have successfully synthesized a number of novel nanomaterials, including vertically-oriented graphene (VG) sheets, three-dimensional (3D) carbon nanostructures comprising few-layer graphene (FLG) sheets inherently connected with CNTs through sp{sup 2} carbons, crumpled graphene (CG)-nanocrystal hybrids, CdSe nanoparticles (NPs), CdS NPs, nanohybrids of metal nitride decorated on nitrogen-doped graphene (NG), QD-carbon nanotube (CNT) and QD-VG-CNT structures, TiO{sub 2}-CdS NPs, and reduced graphene oxide (RGO)-SnO{sub 2} NPs. We further assembled CdSe NPs onto graphene sheets and investigated physical and electronic interactions between CdSe NPs and the graphene. Finally we have demonstrated various applications of these nanomaterials in solar cells (both as photoanodes and counter electrodes), gas sensors, and energy storage devices. This research is potentially transformative since the availability of affordable hybrid nanostructures and their fundamental properties will enable various innovative applications of the multifunctional hybrid nanostructures and thus will accelerate new discoveries and inventions in nanoscience and nanotechnology.

  13. Performance enhancement of thin film silicon solar cells based on distributed Bragg reflector and diffraction grating

    SciTech Connect (OSTI)

    Dubey, R. S.; Saravanan, S.; Kalainathan, S.

    2014-12-15

    The influence of various designing parameters were investigated and explored for high performance solar cells. Single layer grating based solar cell of 50 ?m thickness gives maximum efficiency up to 24 % whereas same efficiency is achieved with the use of three bilayers grating based solar cell of 30 ?m thickness. Remarkably, bilayer grating based solar cell design not only gives broadband absorption but also enhancement in efficiency with reduced cell thickness requirement. This absorption enhancement is attributed to the high reflection and diffraction from DBR and grating respectively. The obtained short-circuit current were 29.6, 32.9, 34.6 and 36.05 mA/cm{sup 2} of 5, 10, 20 and 30 ?m cell thicknesses respectively. These presented designing efforts would be helpful to design and realize new generation of solar cells.

  14. Analysis of Solar Cell Quality Using Voltage Metrics: Preprint

    SciTech Connect (OSTI)

    Toberer, E. S.; Tamboli, A. C.; Steiner, M.; Kurtz, S.

    2012-06-01

    The highest efficiency solar cells provide both excellent voltage and current. Of these, the open-circuit voltage (Voc) is more frequently viewed as an indicator of the material quality. However, since the Voc also depends on the band gap of the material, the difference between the band gap and the Voc is a better metric for comparing material quality of unlike materials. To take this one step further, since Voc also depends on the shape of the absorption edge, we propose to use the ultimate metric: the difference between the measured Voc and the Voc calculated from the external quantum efficiency using a detailed balance approach. This metric is less sensitive to changes in cell design and definition of band gap. The paper defines how to implement this metric and demonstrates how it can be useful in tracking improvements in Voc, especially as Voc approaches its theoretical maximum.

  15. Generalized Optoelectronic Model of Series-Connected Multijunction Solar Cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Geisz, John F.; Steiner, Myles A.; Garcia, Ivan; France, Ryan M.; McMahon, William E.; Osterwald, Carl R.; Friedman, Daniel J.

    2015-11-01

    The emission of light from each junction in a series-connected multijunction solar cell, we found, both complicates and elucidates the understanding of its performance under arbitrary conditions. Bringing together many recent advances in this understanding, we present a general 1-D model to describe luminescent coupling that arises from both voltage-driven electroluminescence and voltage-independent photoluminescence in nonideal junctions that include effects such as Sah-Noyce-Shockley (SNS) recombination with n ≠ 2, Auger recombination, shunt resistance, reverse-bias breakdown, series resistance, and significant dark area losses. The individual junction voltages and currents are experimentally determined from measured optical and electrical inputs and outputs ofmore » the device within the context of the model to fit parameters that describe the devices performance under arbitrary input conditions. Furthermore, our techniques to experimentally fit the model are demonstrated for a four-junction inverted metamorphic solar cell, and the predictions of the model are compared with concentrator flash measurements.« less

  16. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

    Rohatgi, Ajeet; Chen, Zhizhang; Doshi, Parag

    1996-01-01

    Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. Silicon solar cell efficiencies of 16.9% have been achieved. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x.

  17. Manipulating Light to Understand and Improve Solar Cells (494th Brookhaven Lecture)

    SciTech Connect (OSTI)

    Eisaman, Matthew

    2014-04-16

    Energy consumption around the world is projected to approximately triple by the end of the century, according to the 2005 Report from the U.S. Department of Energy's Basic Energy Sciences Workshop on Solar Energy Utilization. Much will change in those next 86 years, but for all the power the world needs—for everything from manufacturing and transportation to air conditioning and charging cell phone batteries—improved solar cells will be crucial to meet this future energy demand with renewable energy sources. At Brookhaven Lab, scientists are probing solar cells and exploring variations within the cells—variations that are so small they are measured in billionths of a meter—in order to make increasingly efficient solar cells and ultimately help reduce the overall costs of deploying solar power plants. Dr. Eisaman will discuss DOE's Sunshot Initiative, which aims to reduce the cost of solar cell-generated electricity by 2020. He will also discuss how he and collaborators at Brookhaven Lab are probing different material compositions within solar cells, measuring how efficiently they collect electrical charge, helping to develop a new class of solar cells, and improving solar-cell manufacturing processes.

  18. Current enhancement of CdTe-based solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Paudel, Naba R.; Poplawsky, Jonathan D.; More, Karren Leslie; Yan, Yanfa

    2015-07-30

    We report on the realization of CdTe solar cell photocurrent enhancement using an n-type CdSe heterojunction partner sputtered on commercial SnO2/SnO2:F coated soda-lime glass substrates. With high-temperature close-space sublimation CdTe deposition followed by CdCl2 activation, this thin-film stack allows for substantial interdiffusion at the CdSe/CdTe interface facilitating a CdSexTe1-x alloy formation. The bowing effect causes a reduced optical bandgap of the alloyed absorber layer and, therefore, leads to current enhancement in the long-wavelength region and a decrease in open-circuit voltage (VOC). To overcome the VOC loss and maintain a high short-circuit current (JSC), the CdTe cell configuration has been modifiedmore » using combined CdS:O/CdSe window layers. The new device structure has demonstrated enhanced collection from both short-and long-wavelength regions as well as a VOC improvement. With an optimized synthesis process, a small-area cell using CdS:O/CdSe window layer showed an efficiency of 15.2% with a VOC of 831 mV, a JSC of 26.3 mA/cm2, and a fill factor of 69.5%, measured under an AM1.5 illumination without antireflection coating. Furthermore, the results provide new directions for further improvement of CdTe-based solar cells.« less

  19. Optically enhanced photon recycling in mechanically stacked multijunction solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Steiner, Myles A.; Geisz, John F.; Ward, J. Scott; Garcia, Ivan; Friedman, Daniel J.; King, Richard R.; Chiu, Philip T.; France, Ryan M.; Duda, Anna; Olavarria, Waldo J.; et al

    2015-11-09

    Multijunction solar cells can be fabricated by mechanically bonding together component cells that are grown separately. Here, we present four-junction four-terminal mechanical stacks composed of GaInP/GaAs tandems grown on GaAs substrates and GaInAsP/GaInAs tandems grown on InP substrates. The component cells were bonded together with a low-index transparent epoxy that acts as an angularly selective reflector to the GaAs bandedge luminescence, while simultaneously transmitting nearly all of the subbandgap light. As determined by electroluminescence measurements and optical modeling, the GaAs subcell demonstrates a higher internal radiative limit and, thus, higher subcell voltage, compared with GaAs subcells without the epoxy reflector.more » The best cells demonstrate 38.8 ± 1.0% efficiency under the global spectrum at 1000 W/m2 and ~ 42% under the direct spectrum at ~100 suns. As a result, eliminating the series resistance is the key challenge for further improving the concentrator cells.« less

  20. Variational method for the minimization of entropy generation in solar cells

    SciTech Connect (OSTI)

    Smit, Sjoerd; Kessels, W. M. M.

    2015-04-07

    In this work, a method is presented to extend traditional solar cell simulation tools to make it possible to calculate the most efficient design of practical solar cells. The method is based on the theory of nonequilibrium thermodynamics, which is used to derive an expression for the local entropy generation rate in the solar cell, making it possible to quantify all free energy losses on the same scale. The framework of non-equilibrium thermodynamics can therefore be combined with the calculus of variations and existing solar cell models to minimize the total entropy generation rate in the cell to find the most optimal design. The variational method is illustrated by applying it to a homojunction solar cell. The optimization results in a set of differential algebraic equations, which determine the optimal shape of the doping profile for given recombination and transport models.

  1. Interface design principles for high-performance organic semiconductor...

    Office of Scientific and Technical Information (OSTI)

    Title: Interface design principles for high-performance organic semiconductor devices Organic solar cells (OSCs) are a promising cost-effective candidate in next generation ...

  2. Non-Linear Luminescent Coupling in Series-Connected Multijunction Solar Cells

    SciTech Connect (OSTI)

    Steiner, M. A.; Geisz, J. F.

    2012-06-18

    The assumption of superposition or linearity of photocurrent with solar flux is widespread for calculations and measurements of solar cells. The well-known effect of luminescent coupling in multijunction solar cells has also been assumed to be linear with excess current. Here we show significant non-linearities in luminescent coupling in III-V multijunction solar cells and propose a simple model based on competition between radiative and nonradiative processes in the luminescent junction to explain these non-linearities. We demonstrate a technique for accurately measuring the junction photocurrents under a specified reference spectrum, that accounts for and quantifies luminescent coupling effects.

  3. Output-increasing, protective cover for a solar cell

    DOE Patents [OSTI]

    Hammerbacher, Milfred D.

    1995-11-21

    A flexible cover (14) for a flexible solar cell (12) protects the cell from the ambient and increases the cell's efficiency. The cell(12)includes silicon spheres (16) held in a flexible aluminum sheet matrix (20,22). The cover (14) is a flexible, protective layer (60) of light-transparent material having a relatively flat upper, free surface (64) and an irregular opposed surface (66). The irregular surface (66) includes first portions (68) which conform to the polar regions (31R) of the spheres (16) and second convex (72) or concave (90) portions (72 or 90) which define spaces (78) in conjunction with the reflective surface (20T) of one aluminum sheet (20). Without the cover (14) light (50) falling on the surface (20T) between the spheres (16) is wasted, that is, it does not fall on a sphere (16). The surfaces of the second portions are non-parallel to the direction of the otherwise wasted light (50), which fact, together with a selected relationship between the refractive indices of the cover and the spaces, result in sufficient diffraction of the otherwise wasted light (50) so that about 25% of it is reflected from the surface (20T) onto a sphere (16).

  4. Design of cascaded low cost solar cell with CuO substrate

    SciTech Connect (OSTI)

    Samson, Mil'shtein; Anup, Pillai; Shiv, Sharma; Garo, Yessayan

    2013-12-04

    For many years the main focus of R and D in solar cells was the development of high-efficiency solar convertors. However with solar technology beginning to be a part of national grids and stand-alone power supplies for variety of individual customers, the emphasis has changed, namely, the cost per kilowatt- hour (kW-hr) started to be an important figure of merit. Although Si does dominate the market of solar convertors, this material has total cost of kilowatt-hour much higher than what the power grid is providing presently to customers. It is well known that the cost of raw semiconductor material is a major factor in formulation of the final cost of a solar cell. That motivated us to search and design a novel solar cell using cheap materials. The new p-i-n solar cell consists of hetero-structure cascade of materials with step by step decreasing energy gap. Since the lattice constant of these three materials do differ not more than 2%, the more expensive epitaxial fabrication methods can be used as well. It should be emphasized that designed solar cell is not a cascade of three solar cells connected in series. Our market study shows that Si solar panel which costs $250–400 / m{sup 2} leads to a cost of $0.12–0.30 / kW-hr. To the contrary, CuO based solar cells with Cadmium compounds on top, would cost $100 / m{sup 2}. This will allow the novel solar cell to produce electricity at a cost of $0.06–0.08 / kW-hr.

  5. NREL Nano-Technology Solar Cell Achieves 18.2% Efficiency - News Releases |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL NREL Nano-Technology Solar Cell Achieves 18.2% Efficiency Breakthrough should eliminate need for anti-reflection layer, cutting costs October 12, 2012 Scientists at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have produced solar cells using nanotechnology techniques at an efficiency - 18.2% -- that is competitive. The breakthrough should be a major step toward helping lower the cost of solar energy. NREL tailored a nanostructured surface while ensuring

  6. NREL and Company Researchers Team Up on Thin-Film Solar Cells - News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Releases | NREL NREL and Company Researchers Team Up on Thin-Film Solar Cells November 12, 2003 Golden, Colo. - An Austin, Tex.-based company is moving toward commercial production of advanced solar cells by using unique facilities and capabilities of the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL). HelioVolt Corp. is attempting to prove the viability of patented technology it has developed for making thin-film Copper Indium Gallium Diselenide (CIGS) solar

  7. Improved Dye-Sensitized Solar Cell (DSSC) for Higher Energy Conversion

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Efficiency - Energy Innovation Portal Dye-Sensitized Solar Cell (DSSC) for Higher Energy Conversion Efficiency University of Colorado Contact CU About This Technology Publications: PDF Document Publication CU2480B (Improved DSSC) Marketing Summary.pdf (213 KB) <em>DSSC schematic.</em> DSSC schematic. Technology Marketing Summary A University of Colorado research group led by Rich Noble has developed a novel approach to dye-sensitized solar cells that increases solar-to-electrical

  8. San Carlos Apache Tribe Energy Organization Analysis & Solar Feasibility Study

    Energy Savers [EERE]

    Energy Organization Analysis & Solar Feasibility Study 2012 funded by grants from the US Department of Energy Tribal Energy Program . San Carlos Apache Mission Statement The Apache People will live a balanced life in harmony with spirituality, culture, language, and family unity in an ever-changing world and shall create a strategic framework for our tribe to grow and prosper. Reservation Boundary The Tribe and Reservation * 90 miles from Phoenix. * 2,400' to 8,300' elevation. * 1.83

  9. Multi-crystalline II-VI based multijunction solar cells and modules

    DOE Patents [OSTI]

    Hardin, Brian E.; Connor, Stephen T.; Groves, James R.; Peters, Craig H.

    2015-06-30

    Multi-crystalline group II-VI solar cells and methods for fabrication of same are disclosed herein. A multi-crystalline group II-VI solar cell includes a first photovoltaic sub-cell comprising silicon, a tunnel junction, and a multi-crystalline second photovoltaic sub-cell. A plurality of the multi-crystalline group II-VI solar cells can be interconnected to form low cost, high throughput flat panel, low light concentration, and/or medium light concentration photovoltaic modules or devices.

  10. Silicon Ink for High-Efficiency Solar Cells Captures a Share of the Market (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-08-01

    Fact sheet on 2011 R&D 100 Award winner Silicon Ink. Liquid silicon has arrived, and with it comes a power boost for solar cells and dramatic cost savings for cell manufacturers.

  11. Glass diffusion source for constraining BSF region of a solar cell

    DOE Patents [OSTI]

    Lesk, I.A.; Pryor, R.A.; Coleman, M.G.

    1982-08-27

    The present invention is directed to a method of fabricating a solar cell comprising simultaneous diffusion of the p and n dopant materials into the solar cell substrate. The simultaneous diffusion process is preceded by deposition of a capping layer impervious to doping by thermal diffusion processes.

  12. Producing Solar Cells By Surface Preparation For Accelerated Nucleation Of Microcrystalline Silicon On Heterogeneous Substrates.

    DOE Patents [OSTI]

    Yang, Liyou; Chen, Liangfan

    1998-03-24

    Attractive multi-junction solar cells and single junction solar cells with excellent conversion efficiency can be produced with a microcrystalline tunnel junction, microcrystalline recombination junction or one or more microcrystalline doped layers by special plasma deposition processes which includes plasma etching with only hydrogen or other specified etchants to enhance microcrystalline growth followed by microcrystalline. nucleation with a doped hydrogen-diluted feedstock.

  13. Organic photovoltaic cells utilizing ultrathin sensitizing layer

    DOE Patents [OSTI]

    Rand, Barry P.; Forrest, Stephen R.

    2011-05-24

    A photosensitive device includes a series of organic photoactive layers disposed between two electrodes. Each layer in the series is in direct contact with a next layer in the series. The series is arranged to form at least one donor-acceptor heterojunction, and includes a first organic photoactive layer comprising a first host material serving as a donor, a thin second organic photoactive layer comprising a second host material disposed between the first and a third organic photoactive layer, and the third organic photoactive layer comprising a third host material serving as an acceptor. The first, second, and third host materials are different. The thin second layer serves as an acceptor relative to the first layer or as a donor relative to the third layer.

  14. PROJECT PROFILE: Silicon-Based Tandem Solar Cells | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    PROJECT PROFILE: Silicon-Based Tandem Solar Cells PROJECT PROFILE: Silicon-Based Tandem Solar Cells Funding Opportunity: SuNLaMP SunShot Subprogram: Photovoltaics Location: National Renewable Energy Laboratory, Golden, CO Amount Awarded: $1,500,000 The project will demonstrate bonded gallium indium phosphide (GaInP) on silicon tandem cells, evaluate the advantages and disadvantages of this method of forming higher-efficiency tandem cells, and compare two- and three-terminal device

  15. NREL, UCLA Certify World Record for Polymer Solar Cell Efficiency - News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Releases | NREL NREL, UCLA Certify World Record for Polymer Solar Cell Efficiency At 8.6% efficiency, cells clear path for devices that can harvest a broader spectrum of the sun's radiation February 29, 2012 Scientists boosted the significance of tandem polymer solar cells by successfully testing cells with low-bandgap polymers that achieved certified conversion efficiencies of 8.62 ± 0.3% with respect to standard terrestrial reporting conditions. That's the highest independently measured

  16. Band filling effects on temperature performance of intermediate band quantum wire solar cells

    SciTech Connect (OSTI)

    Kunets, Vas. P. Furrow, C. S.; Ware, M. E.; Souza, L. D. de; Benamara, M.; Salamo, G. J.; Mortazavi, M.

    2014-08-28

    Detailed studies of solar cell efficiency as a function of temperature were performed for quantum wire intermediate band solar cells grown on the (311)A plane. A remotely doped one-dimensional intermediate band made of self-assembled In{sub 0.4}Ga{sub 0.6}As quantum wires was compared to an undoped intermediate band and a reference p-i-n GaAs sample. These studies indicate that the efficiencies of these solar cells depend on the population of the one-dimensional band by equilibrium free carriers. A change in this population by free electrons under various temperatures affects absorption and carrier transport of non-equilibrium carriers generated by incident light. This results in different efficiencies for both the doped and undoped intermediate band solar cells in comparison with the reference GaAs p-i-n solar cell device.

  17. Electrodeposited cobalt sulfide hole collecting layer for polymer solar cells

    SciTech Connect (OSTI)

    Zampetti, Andrea; De Rossi, Francesca; Brunetti, Francesca; Reale, Andrea; Di Carlo, Aldo; Brown, Thomas M., E-mail: thomas.brown@uniroma2.it [CHOSE (Centre for Hybrid and Organic Solar Energy), Department of Electronic Engineering, University of Rome “Tor Vergata,” Via del Politecnico 1, 00133 Rome (Italy)

    2014-08-11

    In polymer solar cells based on the blend of regioregular poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester, the hole collecting layer has to be endowed with its ionization potential close to or greater than that of P3HT (?5?eV). Conductive polymer blends such as poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and metal oxides such as vanadium pentoxide (V{sub 2}O{sub 5}) and molybdenum trioxide (MoO{sub 3}) satisfy this requirement and have been the most common materials used so far in bulk heterojunction structures. We report here cobalt sulfide (CoS) to be a promising hole collecting material deposited by convenient and room temperature electrodeposition. By simply tuning the CoS electrodeposition parameters, power conversion efficiencies similar (within 15%) to a reference structure with PEDOT:PSS were obtained.

  18. Defect density and dielectric constant in perovskite solar cells

    SciTech Connect (OSTI)

    Samiee, Mehran; Konduri, Siva; Abbas, Hisham A.; Joshi, Pranav; Zhang, Liang; Dalal, Vikram; Ganapathy, Balaji; Kottokkaran, Ranjith; Noack, Max; Kitahara, Andrew

    2014-10-13

    We report on measurement of dielectric constant, mid-gap defect density, Urbach energy of tail states in CH{sub 3}NH{sub 3}PbI{sub x}Cl{sub 1?x} perovskite solar cells. Midgap defect densities were estimated by measuring capacitance vs. frequency at different temperatures and show two peaks, one at 0.66?eV below the conduction band and one at 0.24?eV below the conduction band. The attempt to escape frequency is in the range of 2?Ś?10{sup 11}/s. Quantum efficiency data indicate a bandgap of 1.58?eV. Urbach energies of valence and conduction band are estimated to be ?16 and ?18?meV. Measurement of saturation capacitance indicates that the relative dielectric constant is ?18.

  19. Metal catalyst technique for texturing silicon solar cells

    DOE Patents [OSTI]

    Ruby, Douglas S. (Albuquerque, NM); Zaidi, Saleem H. (Albuquerque, NM)

    2001-01-01

    Textured silicon solar cells and techniques for their manufacture utilizing metal sources to catalyze formation of randomly distributed surface features such as nanoscale pyramidal and columnar structures. These structures include dimensions smaller than the wavelength of incident light, thereby resulting in a highly effective anti-reflective surface. According to the invention, metal sources present in a reactive ion etching chamber permit impurities (e.g. metal particles) to be introduced into a reactive ion etch plasma resulting in deposition of micro-masks on the surface of a substrate to be etched. Separate embodiments are disclosed including one in which the metal source includes one or more metal-coated substrates strategically positioned relative to the surface to be textured, and another in which the walls of the reaction chamber are pre-conditioned with a thin coating of metal catalyst material.

  20. Organic photovoltaic cells utilizing ultrathin sensitizing layer

    DOE Patents [OSTI]

    Forrest, Stephen R.; Yang, Fan; Rand, Barry P.

    2011-09-06

    A photosensitive device includes a plurality of organic photoconductive materials disposed in a stack between a first electrode and a second electrode, including a first continuous layer of donor host material, a second continuous layer of acceptor host material, and at least one other organic photoconductive material disposed as a plurality of discontinuous islands between the first continuous layer and the second continuous layer. Each of these other photoconductive materials has an absorption spectra different from the donor host material and the acceptor host material. Preferably, each of the discontinuous islands consists essentially of a crystallite of the respective organic photoconductive material, and more preferably, the crystallites are nanocrystals.

  1. Solar cell modules with improved backskin and methods for forming same

    DOE Patents [OSTI]

    Hanoka, Jack I. (Brookline, MA)

    1998-04-21

    A laminated solar cell module with a backskin layer that reduces the materials and labor required during the manufacturing process. The solar cell module includes a rigid front support layer formed of light transmitting material having first and second surfaces. A transparent encapsulant layer has a first surface disposed adjacent the second surface of the front support layer. A plurality of interconnected solar cells have a first surface disposed adjacent a second surface of the transparent encapsulant layer. The backskin layer is formed of a thermoplastic olefin, which includes first ionomer, a second ionomer, glass fiber, and carbon black. A first surface of the backskin layer is disposed adjacent a second surface of the interconnected solar cells. The transparent encapsulant layer and the backskin layer, in combination, encapsulate the interconnected solar cells. An end portion of the backskin layer can be wrapped around the edge of the module for contacting the first surface of the front support layer to form an edge seal. A laminated solar cell module with a backskin layer that reduces the materials and labor required during the manufacturing process. The solar cell module includes a rigid front support layer formed of light transmitting material having first and second surfaces. A transparent encapsulant layer has a first surface disposed adjacent the second surface of the front support layer. A plurality of interconnected solar cells have a first surface disposed adjacent a second surface of the transparent encapsulant layer. The backskin layer is formed of a thermoplastic olefin, which includes first ionomer, a second ionomer, glass fiber, and carbon black. A first surface of the backskin layer is disposed adjacent a second surface of the interconnected solar cells. The transparent encapsulant layer and the backskin layer, in combination, encapsulate the interconnected solar cells. An end portion of the backskin layer can be wrapped around the edge of the module for contacting the first surface of the front support layer to form an edge seal.

  2. CIBS Solar Cell Development Final Scientific/Technical Report

    SciTech Connect (OSTI)

    Exstrom, Christopher L.; Soukup, Rodney J.; Ianno, Natale J.

    2011-09-28

    Efforts to fabricate and study a new photovoltaic material, copper indium boron diselenide (CuInxB1-xSe2 or CIBS), were undertaken. Attempts to prepare CIBS using sputtering deposition techniques resulted in segregation of boron from the rest of elements in the material. CIBS nanocrystals were prepared from the reaction of elemental Se with CuCl, InCl3, and boric acid in solution, but the product material quickly decomposed upon heating that was required in attempts to convert the nanocrystals into a thin film. The investigation of the reasons for the lack of CIBS material stability led to new structure-property studies of closely-related photovoltaic systems as well as studies of new solar cell materials and processing methods that could enhance the development of next-generation solar technologies. A detailed compositional study of CuIn1-xAlxSe2 (CIAS, a system closely related to CIBS) revealed a non-linear correlation between crystal lattice size and the Al/(In+Al) ratios with dual-phase formation being observed. A new nanocrystal-to-thin-film processing method was developed for the preparation of CuIn1-xGaxSe2 (CIGS) thin films in which colloidal Se particles are sprayed in contact with CuIn1-xGaxS2 nanoparticles and heated in an argon atmosphere with no other Se source in the system. The process is non-vacuum and does not require toxic gases such as Se vapor or H2Se. Expertise gained from these studies was applied to new research in the preparation of thin-film pyrite FeS2, an attractive earth-abundant candidate material for next-generation photovoltaics. Three methods successfully produced pure pyrite FeS2 films: sulfurization of sputtered Fe films, chemical bath deposition, and sulfurization of Fe2O3 sol-gel precursors. The last method produced pinhole-free films that may be viable for device development. Nickel, platinum, and possibly carbon would appear to serve as good ohmic contact materials. While CdS has a reasonable conduction band energy match to serve as an n-type buffer material in a pyrite FeS2-based solar cell, the less toxic SnS2 is being explored for this purpose.

  3. New Solar Cell Is More Efficient, Less Costly - News Feature | NREL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Solar Cell Is More Efficient, Less Costly November 8, 2013 In this photo, a researcher in glasses holds a solar wafer about the size of a CD case. In the background are two computer screens displaying graphs of the performance of similar wafers. Enlarge image NREL Principal Scientist Mowafak Al-Jassim holds a TetraSun PV cell in the cathodoluminescence lab at NREL. The TetraSun cell combines increased efficiency and low cost, breaking the usual rules for solar cells. Credit: Dennis Schroeder

  4. Incorporating photon recycling into the analytical drift-diffusion model of high efficiency solar cells

    SciTech Connect (OSTI)

    Lumb, Matthew P.; Steiner, Myles A.; Geisz, John F.; Walters, Robert J.

    2014-11-21

    The analytical drift-diffusion formalism is able to accurately simulate a wide range of solar cell architectures and was recently extended to include those with back surface reflectors. However, as solar cells approach the limits of material quality, photon recycling effects become increasingly important in predicting the behavior of these cells. In particular, the minority carrier diffusion length is significantly affected by the photon recycling, with consequences for the solar cell performance. In this paper, we outline an approach to account for photon recycling in the analytical Hovel model and compare analytical model predictions to GaAs-based experimental devices operating close to the fundamental efficiency limit.

  5. NREL and Stanford Team up on Peel-and-Stick Solar Cells - News Releases |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL and Stanford Team up on Peel-and-Stick Solar Cells Devices could charge battery-powered products in the future January 10, 2013 It may be possible soon to charge cell phones, change the tint on windows, or power small toys with peel-and-stick versions of solar cells, thanks to a partnership between Stanford University and the U.S. Department of Energy's National Renewable Energy Laboratory (NREL). A scientific paper, "Peel and Stick: Fabricating Thin Film Solar Cells on Universal

  6. In Situ X-Ray Scattering Helps Optimize Printed Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In Situ X-Ray Scattering Helps Optimize Printed Solar Cells In Situ X-Ray Scattering Helps Optimize Printed Solar Cells Print Wednesday, 25 February 2015 00:00 Plastic solar cells that can be printed on flexible sheets with an ink-like solution show a lot of potential as a source of lightweight, inexpensive renewable energy. However, much of the power-conversion efficiency of such cells gets lost in the translation from small-scale lab studies to large-scale manufacturing processes. To help gain

  7. Automatic generation and analysis of solar cell IV curves

    SciTech Connect (OSTI)

    Kraft, Steven M.; Jones, Jason C.

    2014-06-03

    A photovoltaic system includes multiple strings of solar panels and a device presenting a DC load to the strings of solar panels. Output currents of the strings of solar panels may be sensed and provided to a computer that generates current-voltage (IV) curves of the strings of solar panels. Output voltages of the string of solar panels may be sensed at the string or at the device presenting the DC load. The DC load may be varied. Output currents of the strings of solar panels responsive to the variation of the DC load are sensed to generate IV curves of the strings of solar panels. IV curves may be compared and analyzed to evaluate performance of and detect problems with a string of solar panels.

  8. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    spectroscopy and scattering studies conducted by North Carolina State University and Cambridge University researchers at ALS Beamlines 5.3.2 and 7.3.3 found a substantial amount...

  9. New Morphological Paradigm Uncovered in Organic Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    potential. Models describing critical device functions such as charge separation and transport often depend on simplistic morphological assumptions, including discrete...

  10. Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Conversion Efficiency Solar Energy Wind Energy Water ... Infrastructure Hydrogen Production Market Transformation ... Tribal Energy Program Intellectual Property Current EC ...

  11. Light Trapping for High Efficiency Heterojunction Crystalline Si Solar Cells: Preprint

    SciTech Connect (OSTI)

    Wang, Q.; Xu, Y.; Iwaniczko, E.; Page, M.

    2011-04-01

    Light trapping plays an important role to achieve high short circuit current density (Jsc) and high efficiency for amorphous/crystalline Si heterojunction solar cells. Si heterojunction uses hydrogenated amorphous Si for emitter and back contact. This structure of solar cell posses highest open circuit voltage of 0.747 V at one sun for c-Si based solar cells. It also suggests that over 25% record-high efficiency is possible with further improvement of Jsc. Light trapping has two important tasks. The first one is to reduce the surface reflectance of light to zero for the solar spectrum that Si has a response. The second one is to increase the effective absorption length to capture all the photon. For Si heterojunction solar cell, surface texturing, anti-reflectance indium tin oxides (ITO) layer at the front and back are the key area to improve the light trapping.

  12. Bifacial solar cell with SnS absorber by vapor transport deposition

    SciTech Connect (OSTI)

    Wangperawong, Artit; Hsu, Po-Chun; Yee, Yesheng; Herron, Steven M.; Clemens, Bruce M.; Cui, Yi; Bent, Stacey F.

    2014-10-27

    The SnS absorber layer in solar cell devices was produced by vapor transport deposition (VTD), which is a low-cost manufacturing method for solar modules. The performance of solar cells consisting of Si/Mo/SnS/ZnO/indium tin oxide (ITO) was limited by the SnS layer's surface texture and field-dependent carrier collection. For improved performance, a fluorine doped tin oxide (FTO) substrate was used in place of the Mo to smooth the topography of the VTD SnS and to make bifacial solar cells, which are potentially useful for multijunction applications. A bifacial SnS solar cell consisting of glass/FTO/SnS/CdS/ZnO/ITO demonstrated front- and back-side power conversion efficiencies of 1.2% and 0.2%, respectively.

  13. Fabricating amorphous silicon solar cells by varying the temperature _of the substrate during deposition of the amorphous silicon layer

    DOE Patents [OSTI]

    Carlson, David E. (Yardley, PA)

    1982-01-01

    An improved process for fabricating amorphous silicon solar cells in which the temperature of the substrate is varied during the deposition of the amorphous silicon layer is described. Solar cells manufactured in accordance with this process are shown to have increased efficiencies and fill factors when compared to solar cells manufactured with a constant substrate temperature during deposition of the amorphous silicon layer.

  14. Development of Novel Front Contract Pastes for Crystalline Silicon Solar Cells

    SciTech Connect (OSTI)

    Duty, C.; Jellison, D. G.E. P.; Joshi, P.

    2012-04-05

    In order to improve the efficiencies of silicon solar cells, paste to silicon contact formation mechanisms must be more thoroughly understood as a function of paste chemistry, wafer properties and firing conditions. Ferro Corporation has been involved in paste development for over 30 years and has extensive expertise in glass and paste formulations. This project has focused on the characterization of the interface between the top contact material (silver paste) and the underlying silicon wafer. It is believed that the interface between the front contact silver and the silicon wafer plays a dominant role in the electrical performance of the solar cell. Development of an improved front contact microstructure depends on the paste chemistry, paste interaction with the SiNx, and silicon (“Si”) substrate, silicon sheet resistivity, and the firing profile. Typical front contact ink contains silver metal powders and flakes, glass powder and other inorganic additives suspended in an organic medium of resin and solvent. During fast firing cycles glass melts, wets, corrodes the SiNx layer, and then interacts with underlying Si. Glass chemistry is also a critical factor in the development of an optimum front contact microstructure. Over the course of this project, several fundamental characteristics of the Ag/Si interface were documented, including a higher-than-expected distribution of voids along the interface, which could significantly impact electrical conductivity. Several techniques were also investigated for the interfacial analysis, including STEM, EDS, FIB, EBSD, and ellipsometry.

  15. Study of minority carrier diffusion lengths in photoactive layers of multijunction solar cells

    SciTech Connect (OSTI)

    Mintairov, S. A. Andreev, V. M.; Emelyanov, V. M.; Kalyuzhnyy, N. A.; Timoshina, N. K.; Shvarts, M. Z.; Lantratov, V. M.

    2010-08-15

    A technique for determining a minority carrier's diffusion length in photoactive III-V layers of solar cells by approximating their spectral characteristics is presented. Single-junction GaAs, Ge and multi-junction GaAs/Ge, GaInP/GaAs, and GaInP/GaInAs/Ge solar cells fabricated by hydride metal-organic vapor-phase epitaxy (H-MOVPE) have been studied. The dependences of the minority carrier diffusion length on the doping level of p-Ge and n-GaAs are determined. It is shown that the parameters of solid-state diffusion of phosphorus atoms to the p-Ge substrate from the n-GaInP nucleation layer are independent of the thickness of the latter within 35-300 nm. It is found that the diffusion length of subcells of multijunction structures in Ga(In)As layers is smaller in comparison with that of single-junction structures.

  16. Semi-transparent perovskite solar cells for tandems with silicon and CIGS

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bailie, Colin D.; Christoforo, M. Greyson; Mailoa, Jonathan P.; Bowring, Andrea R.; Unger, Eva L.; Nguyen, William H.; Burschka, Julian; Pellet, Norman; Lee, Jungwoo Z.; GrÀtzel, Michael; et al

    2014-12-23

    A promising approach for upgrading the performance of an established low-bandgap solar technology without adding much cost is to deposit a high bandgap polycrystalline semiconductor on top to make a tandem solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem configuration onto copper indium gallium diselenide (CIGS) and low-quality multicrystalline silicon (Si) to achieve solid-state polycrystalline tandem solar cells with a net improvement in efficiency over the bottom cell alone. Furthermore, this work paves the way for integrating perovskites into a low-costmore » and high-efficiency (>25%) tandem cell.« less

  17. Semi-transparent perovskite solar cells for tandems with silicon and CIGS

    SciTech Connect (OSTI)

    Bailie, Colin D.; Christoforo, M. Greyson; Mailoa, Jonathan P.; Bowring, Andrea R.; Unger, Eva L.; Nguyen, William H.; Burschka, Julian; Pellet, Norman; Lee, Jungwoo Z.; Grätzel, Michael; Noufi, Rommel; Buonassisi, Tonio; Salleo, Alberto; McGehee, Michael D.

    2014-12-23

    A promising approach for upgrading the performance of an established low-bandgap solar technology without adding much cost is to deposit a high bandgap polycrystalline semiconductor on top to make a tandem solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem configuration onto copper indium gallium diselenide (CIGS) and low-quality multicrystalline silicon (Si) to achieve solid-state polycrystalline tandem solar cells with a net improvement in efficiency over the bottom cell alone. Furthermore, this work paves the way for integrating perovskites into a low-cost and high-efficiency (>25%) tandem cell.

  18. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

    Rohatgi, A.; Doshi, P.; Tate, J.K.; Mejia, J.; Chen, Z.

    1998-06-16

    Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime {tau} and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime {tau} and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO{sub x}. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure. 28 figs.

  19. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

    Rohatgi, Ajeet; Doshi, Parag; Tate, John Keith; Mejia, Jose; Chen, Zhizhang

    1998-06-16

    Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure.

  20. Recent improvements in materials for thin GaAs and multibandgap solar cells

    SciTech Connect (OSTI)

    Benner, J.P.

    1985-05-01

    The High Efficiency Concepts Program at SERI supports research on III-V compound semiconductors with the objective of achieving the maximum attainable photovoltaic conversion efficiencies for terrestrial solar electric power. The outcome of this research may also affect the future of space photovoltaic cells. While the interest in thin-film, high-efficiency solar cells for terrestrial applications is driven principally by consideration of system costs, such cells would also improve the power density of space power arrays.

  1. Multi-phase back contacts for CIS solar cells

    DOE Patents [OSTI]

    Rockett, Angus A. (505 Park Haven Ct., Champaign, IL 61820); Yang, Li-Chung (1107 W. Green St. #328, Urbana, IL 61801)

    1995-01-01

    Multi-phase, single layer, non-interdiffusing M-Mo back contact metallized films, where M is selected from Cu, Ga, or mixtures thereof, for CIS cells are deposited by a sputtering process on suitable substrates, preferably glass or alumina, to prevent delamination of the CIS from the back contact layer. Typical CIS compositions include CuXSe.sub.2 where X is In or/and Ga. The multi-phase mixture is deposited on the substrate in a manner to provide a columnar microstructure, with micro-vein Cu or/and Ga regions which partially or fully vertically penetrate the entire back contact layer. The CIS semiconductor layer is then deposited by hybrid sputtering and evaporation process. The Cu/Ga-Mo deposition is controlled to produce the single layer two-phase columnar morphology with controllable Cu or Ga vein size less than about 0.01 microns in width. During the subsequent deposition of the CIS layer, the columnar Cu/Ga regions within the molybdenum of the Cu/Ga-Mo back layer tend to partially leach out, and are replaced by columns of CIS. Narrower Cu and/or Ga regions, and those with fewer inner connections between regions, leach out more slowly during the subsequent CIS deposition. This gives a good mechanical and electrical interlock of the CIS layer into the Cu/Ga-Mo back layer. Solar cells employing In-rich CIS semiconductors bonded to the multi-phase columnar microstructure back layer of this invention exhibit vastly improved photo-electrical conversion on the order of 17% greater than Mo alone, improved uniformity of output across the face of the cell, and greater Fill Factor.

  2. Multi-phase back contacts for CIS solar cells

    DOE Patents [OSTI]

    Rockett, A.A.; Yang, L.C.

    1995-12-19

    Multi-phase, single layer, non-interdiffusing M-Mo back contact metallized films, where M is selected from Cu, Ga, or mixtures thereof, for CIS cells are deposited by a sputtering process on suitable substrates, preferably glass or alumina, to prevent delamination of the CIS from the back contact layer. Typical CIS compositions include CuXSe{sub 2} where X is In or/and Ga. The multi-phase mixture is deposited on the substrate in a manner to provide a columnar microstructure, with micro-vein Cu or/and Ga regions which partially or fully vertically penetrate the entire back contact layer. The CIS semiconductor layer is then deposited by hybrid sputtering and evaporation process. The Cu/Ga-Mo deposition is controlled to produce the single layer two-phase columnar morphology with controllable Cu or Ga vein size less than about 0.01 microns in width. During the subsequent deposition of the CIS layer, the columnar Cu/Ga regions within the molybdenum of the Cu/Ga-Mo back layer tend to partially leach out, and are replaced by columns of CIS. Narrower Cu and/or Ga regions, and those with fewer inner connections between regions, leach out more slowly during the subsequent CIS deposition. This gives a good mechanical and electrical interlock of the CIS layer into the Cu/Ga-Mo back layer. Solar cells employing In-rich CIS semiconductors bonded to the multi-phase columnar microstructure back layer of this invention exhibit vastly improved photo-electrical conversion on the order of 17% greater than Mo alone, improved uniformity of output across the face of the cell, and greater Fill Factor. 15 figs.

  3. Enhanced efficiency of graphene-silicon Schottky junction solar cells by doping with Au nanoparticles

    SciTech Connect (OSTI)

    Liu, X.; Zhang, X. W. Yin, Z. G.; Meng, J. H.; Gao, H. L.; Zhang, L. Q.; Zhao, Y. J.; Wang, H. L.

    2014-11-03

    We have reported a method to enhance the performance of graphene-Si (Gr/Si) Schottky junction solar cells by introducing Au nanoparticles (NPs) onto the monolayer graphene and few-layer graphene. The electron transfer between Au NPs and graphene leads to the increased work function and enhanced electrical conductivity of graphene, resulting in a remarkable improvement of device efficiency. By optimizing the initial thickness of Au layers, the power conversion efficiency of Gr/Si solar cells can be increased by more than three times, with a maximum value of 7.34%. These results show a route for fabricating efficient and stable Gr/Si solar cells.

  4. Enhanced performance of polymer:fullerene bulk heterojunction solar cells upon graphene addition

    SciTech Connect (OSTI)

    Robaeys, Pieter Dierckx, Wouter; Dexters, Wim; Spoltore, Donato; Drijkoningen, Jeroen; Bonaccorso, Francesco; Bourgeois, Emilie; D'Haen, Jan; Haenen, Ken; Manca, Jean V.; Nesladek, Milos; Liesenborgs, Jori; Van Reeth, Frank; Lombardo, Antonio; Ferrari, Andrea C.

    2014-08-25

    Graphene has potential for applications in solar cells. We show that the short circuit current density of P3HT (Poly(3-hexylthiophene-2,5-diyl):PCBM((6,6)-Phenyl C61 butyric acid methyl ester) solar cells is enhanced by 10% upon the addition of graphene, with a 15% increase in the photon to electric conversion efficiency. We discuss the performance enhancement by studying the crystallization of P3HT, as well as the electrical transport properties. We show that graphene improves the balance between electron and hole mobilities with respect to a standard P3HT:PCBM solar cell.

  5. Award-Winning Etching Process Cuts Solar Cell Costs (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-08-01

    NREL scientists have invented the 'black silicon' nanocatalytic wet-chemical etch, an inexpensive, one-step process that literally turns the solar cells black, allowing them to absorb more than 98% of incident sunlight. The process costs just a few cents per watt of solar-cell power-producing capacity. Increases in manufactured cell efficiencies of up to 0.8% are possible because of the reduced reflectance of black silicon. This would reduce silicon solar module costs by $5-$10 per module.

  6. EH AND S ANALYSIS OF DYE-SENSITIZED PHOTOVOLTAIC SOLAR CELL PRODUCTION.

    SciTech Connect (OSTI)

    BOWERMAN,B.; FTHENAKIS,V.

    2001-10-01

    Photovoltaic solar cells based on a dye-sensitized nanocrystalline titanium dioxide photoelectrode have been researched and reported since the early 1990's. Commercial production of dye-sensitized photovoltaic solar cells has recently been reported in Australia. In this report, current manufacturing methods are described, and estimates are made of annual chemical use and emissions during production. Environmental, health and safety considerations for handling these materials are discussed. This preliminary EH and S evaluation of dye-sensitized titanium dioxide solar cells indicates that some precautions will be necessary to mitigate hazards that could result in worker exposure. Additional information required for a more complete assessment is identified.

  7. Getting More Electricity out of Solar Cells | U.S. DOE Office of Science

    Office of Science (SC) Website

    (SC) Getting More Electricity out of Solar Cells Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News EFRC Events DOE Announcements Publications History Contact BES Home 05.27.14 Getting More Electricity out of Solar Cells Print Text Size: A A A Subscribe FeedbackShare Page New MIT model can guide design of solar cells that produce less waste heat, more useful current. This work, featured in the Office of Science's Stories of

  8. Getting More Electricity out of Solar Cells | U.S. DOE Office of Science

    Office of Science (SC) Website

    (SC) Getting More Electricity out of Solar Cells News News Home Featured Articles 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Science Highlights Presentations & Testimony News Archives Communications and Public Affairs Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 05.27.14 Getting More Electricity out of Solar Cells New MIT model can guide design of solar cells that

  9. NREL Reports 31.1% Efficiency for III-V Solar Cell - News Releases | NREL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Reports 31.1% Efficiency for III-V Solar Cell Conversion-efficiency mark is a world record for a two-junction solar cell measured under one-sun illumination June 24, 2013 The Energy Department's National Renewable Energy Lab has announced a world record of 31.1% conversion efficiency for a two-junction solar cell under one sun of illumination. NREL Scientist Myles Steiner announced the new record June 19 at the 39th IEEE Photovoltaic Specialists Conference in Tampa, Fla. The previous record of

  10. NREL Solar Cell Sets World Efficiency Record at 40.8 Percent - News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Releases | NREL NREL Solar Cell Sets World Efficiency Record at 40.8 Percent August 13, 2008 Scientists at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have set a world record in solar cell efficiency with a photovoltaic device that converts 40.8 percent of the light that hits it into electricity. This is the highest confirmed efficiency of any photovoltaic device to date. The inverted metamorphic triple-junction solar cell was designed, fabricated and

  11. NREL, CSEM Jointly Set New Efficiency Record with Dual-Junction Solar Cell

    SciTech Connect (OSTI)

    2016-01-01

    Scientists set a new world record for converting non-concentrated sunlight into electricity using a dual-junction III-V/Si solar cell. National Renewable Energy Laboratory (NREL) and Swiss Center for Electronics and Microtechnology (CSEM) scientists have collaborated to create a novel tandem solar cell that operates at 29.8% conversion efficiency under non-concentrator (1-sun) conditions. In comparison, the 1-sun efficiency of a silicon (Si) single-junction solar cell is probably still a few years away from converging on its practical limit of about 26%.

  12. Stable, high-efficiency amorphous silicon solar cells with low hydrogen content

    SciTech Connect (OSTI)

    Fortmann, C.M.; Hegedus, S.S. )

    1992-12-01

    Results and conclusions obtained during a research program of the investigation of amorphous silicon and amorphous silicon based alloy materials and solar cells fabricated by photo-chemical vapor and glow discharge depositions are reported. Investigation of the effects of the hydrogen content in a-si:H i-layers in amorphous silicon solar cells show that cells with lowered hydrogen content i-layers are more stable. A classical thermodynamic formulation of the Staebler-Wronski effect has been developed for standard solar cell operating temperatures and illuminations. Methods have been developed to extract a lumped equivalent circuit from the current voltage characteristic of a single junction solar cell in order to predict its behavior in a multijunction device.

  13. High-Performance All Air-Processed Polymer-Fullerene Bulk Heterojunction Solar Cells

    SciTech Connect (OSTI)

    Black, C.T.; Nam, C.-Y.; Su, D.

    2009-10-23

    High photovoltaic device performance is demonstrated in ambient-air-processed bulk heterojunction solar cells having an active blend layer of organic poly(3-hexylthiophene) (P3HT): [6,6]-phenyl-C{sub 61}-butyric acid methyl ester (PCBM), with power conversion efficiencies as high as 4.1%, which is comparable to state-of-the-art bulk heterojunction devices fabricated in air-free environments. High-resolution transmission electron microscopy is combined with detailed analysis of electronic carrier transport in order to quantitatively understand the effects of oxygen exposure and different thermal treatments on electronic conduction through the highly nanostructured active blend network. Improvement in photovoltaic device performance by suitable post-fabrication thermal processing results from the reduced oxygen charge trap density in the active blend layer and is consistent with a corresponding slight increase in thickness of an {approx}4 nm aluminum oxide hole-blocking layer present at the electron-collecting contact interface.

  14. Effects of Magnetic Nanoparticles and External Magnetostatic Field on the Bulk Heterojunction Polymer Solar Cells

    SciTech Connect (OSTI)

    Wang, Kai; Yi, Chao; Liu, Chang; Hu, Xiaowen; Chuang, Steven; Gong, Xiong

    2015-03-18

    The price of energy to separate tightly bound electron-hole pair (or charge-transfer state) and extract freely movable charges from low-mobility materials represents fundamental losses for many low-cost photovoltaic devices. In bulk heterojunction (BHJ) polymer solar cells (PSCs), approximately 50% of the total efficiency lost among all energy loss pathways is due to the photogenerated charge carrier recombination within PSCs and low charge carrier mobility of disordered organic materials. To address these issues, we introduce magnetic nanoparticles (MNPs) and orientate these MNPS within BHJ composite by an external magnetostatic field. Over 50% enhanced efficiency was observed from BHJ PSCs incorporated with MNPs and an external magnetostatic field alignment when compared to the control BHJ PSCs. The optimization of BHJ thin film morphology, suppression of charge carrier recombination, and enhancement in charge carrier collection result in a greatly increased short-circuit current density and fill factor, as a result, enhanced power conversion efficiency.

  15. Molecular ferroelectric contributions to anomalous hysteresis in hybrid perovskite solar cells

    SciTech Connect (OSTI)

    Frost, Jarvist M.; Butler, Keith T.; Walsh, Aron

    2014-08-01

    We report a model describing the molecular orientation disorder in CH{sub 3}NH{sub 3}PbI{sub 3}, solving a classical Hamiltonian parametrised with electronic structure calculations, with the nature of the motions informed by ab initio molecular dynamics. We investigate the temperature and static electric field dependence of the equilibrium ferroelectric (molecular) domain structure and resulting polarisability. A rich domain structure of twinned molecular dipoles is observed, strongly varying as a function of temperature and applied electric field. We propose that the internal electrical fields associated with microscopic polarisation domains contribute to hysteretic anomalies in the current-voltage response of hybrid organic-inorganic perovskite solar cells due to variations in electron-hole recombination in the bulk.

  16. NREL Explores Earth-Abundant Materials for Future Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-10-01

    Researchers at the National Renewable Energy Laboratory (NREL) are using a theory-driven technique - sequential cation mutation - to understand the nature and limitations of promising solar cell materials that can replace today's technologies. Finding new materials that use Earth-abundant elements and are easily manufactured is important for large-scale solar electricity deployment.

  17. Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas ...

  18. Amorphous silicon passivated contacts for diffused junction silicon solar cells

    SciTech Connect (OSTI)

    Bullock, J. Yan, D.; Wan, Y.; Cuevas, A.; Demaurex, B.; Hessler-Wyser, A.; De Wolf, S.

    2014-04-28

    Carrier recombination at the metal contacts is a major obstacle in the development of high-performance crystalline silicon homojunction solar cells. To address this issue, we insert thin intrinsic hydrogenated amorphous silicon [a-Si:H(i)] passivating films between the dopant-diffused silicon surface and aluminum contacts. We find that with increasing a-Si:H(i) interlayer thickness (from 0 to 16?nm) the recombination loss at metal-contacted phosphorus (n{sup +}) and boron (p{sup +}) diffused surfaces decreases by factors of ?25 and ?10, respectively. Conversely, the contact resistivity increases in both cases before saturating to still acceptable values of ? 50 m? cm{sup 2} for n{sup +} and ?100 m? cm{sup 2} for p{sup +} surfaces. Carrier transport towards the contacts likely occurs by a combination of carrier tunneling and aluminum spiking through the a-Si:H(i) layer, as supported by scanning transmission electron microscopy–energy dispersive x-ray maps. We explain the superior contact selectivity obtained on n{sup +} surfaces by more favorable band offsets and capture cross section ratios of recombination centers at the c-Si/a-Si:H(i) interface.

  19. Quantum Dot Solar Cells: High Efficiency through Multiple Exciton Generation

    SciTech Connect (OSTI)

    Hanna, M. C.; Ellingson, R. J.; Beard, M.; Yu, P.; Micic, O. I.; Nozik, A. J.; c.

    2005-01-01

    Impact ionization is a process in which absorbed photons in semiconductors that are at least twice the bandgap can produce multiple electron-hole pairs. For single-bandgap photovoltaic devices, this effect produces greatly enhanced theoretical thermodynamic conversion efficiencies that range from 45-85%, depending upon solar concentration, the cell temperature, and the number of electron-hole pairs produced per photon. For quantum dots (QDs), electron-hole pairs exist as excitons. We have observed astoundingly efficient multiple exciton generation (MEG) in QDs of PbSe (bulk Eg = 0.28 eV), ranging in diameter from 3.9 to 5.7nm (Eg = 0.73, 0.82, and 0.91 eV, respectively). The effective masses of electron and holes are about equal in PbSe, and the onset for efficient MEG occurs at about three times the QD HOMO-LUMO transition (its ''bandgap''). The quantum yield rises quickly after the onset and reaches 300% at 4 x Eg (3.64 eV) for the smallest QD; this means that every QD in the sample produces three electron-hole pairs/photon.

  20. Enhanced conversion efficiency in wide-bandgap GaNP solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sukrittanon, Supanee; Liu, Ren; Ro, Yun Goo; Pan, Janet L.; Jungjohann, Katherine Leigh; Tu, Charles W.; Dayeh, Shadi A.

    2015-10-12

    In this study, we demonstrate –2.05 eV dilute nitride GaNP solar cells on GaP substrates for potential use as the top junction in dual-junction integrated cells on Si. By adding a small amount of N into indirect-bandgap GaP, GaNP has several extremely important attributes: a direct-bandgap that is also tunable, and easily attained lattice-match with Si. Our best GaNP solar cell ([N] –1.8%, Eg –2.05 eV) achieves an efficiency of 7.9%, even in the absence of a window layer. This GaNP solar cell's efficiency is 3× higher than the most efficient GaP solar cell to date and higher than othermore » solar cells with similar direct bandgap (InGaP, GaAsP). Through a systematic study of the structural, electrical, and optical properties of the device, efficient broadband optical absorption and enhanced solar cell performance are demonstrated.« less

  1. Performance of Hydrogenated a-Si:H Solar Cells with Downshifting Coating: Preprint

    SciTech Connect (OSTI)

    Nemeth, B.; Xu, Y.; Wang, H.; Sun, T.; Lee, B. G.; Duda, A.; Wang, Q.

    2011-05-01

    We apply a thin luminescent downshifting (LDS) coating to a hydrogenated amorphous Si (a-Si:H) solar cell and study the mechanism of possible current enhancement. The conversion material used in this study converts wavelengths below 400 nm to a narrow line around 615 nm. This material is coated on the front of the glass of the a-Si:H solar cell with a glass/TCO/p/i/n/Ag superstrate configuration. The initial efficiency of the solar cell without the LDS coating is above 9.0 % with open circuit voltage of 0.84 V. Typically, the spectral response below 400 nm of an a-Si:H solar cell is weaker than that at 615 nm. By converting ultraviolet (UV) light to red light, the solar cell will receive more red photons; therefore, solar cell performance is expected to improve. We observe evidence of downshifting in reflectance spectra. The cell Jsc decreases by 0.13 mA/cm2, and loss mechanisms are identified.

  2. Enhanced conversion efficiency in wide-bandgap GaNP solar cells

    SciTech Connect (OSTI)

    Sukrittanon, Supanee; Liu, Ren; Ro, Yun Goo; Pan, Janet L.; Jungjohann, Katherine Leigh; Tu, Charles W.; Dayeh, Shadi A.

    2015-10-12

    In this study, we demonstrate –2.05 eV dilute nitride GaNP solar cells on GaP substrates for potential use as the top junction in dual-junction integrated cells on Si. By adding a small amount of N into indirect-bandgap GaP, GaNP has several extremely important attributes: a direct-bandgap that is also tunable, and easily attained lattice-match with Si. Our best GaNP solar cell ([N] –1.8%, Eg –2.05 eV) achieves an efficiency of 7.9%, even in the absence of a window layer. This GaNP solar cell's efficiency is 3× higher than the most efficient GaP solar cell to date and higher than other solar cells with similar direct bandgap (InGaP, GaAsP). Through a systematic study of the structural, electrical, and optical properties of the device, efficient broadband optical absorption and enhanced solar cell performance are demonstrated.

  3. Numerical simulation: Toward the design of high-efficiency planar perovskite solar cells

    SciTech Connect (OSTI)

    Liu, Feng; Zhu, Jun E-mail: sydai@ipp.ac.cn; Wei, Junfeng; Li, Yi; Lv, Mei; Yang, Shangfeng; Zhang, Bing; Yao, Jianxi; Dai, Songyuan E-mail: sydai@ipp.ac.cn

    2014-06-23

    Organo-metal halide perovskite solar cells based on planar architecture have been reported to achieve remarkably high power conversion efficiency (PCE, >16%), rendering them highly competitive to the conventional silicon based solar cells. A thorough understanding of the role of each component in solar cells and their effects as a whole is still required for further improvement in PCE. In this work, the planar heterojunction-based perovskite solar cells were simulated with the program AMPS (analysis of microelectronic and photonic structures)-1D. Simulation results revealed a great dependence of PCE on the thickness and defect density of the perovskite layer. Meanwhile, parameters including the work function of the back contact as well as the hole mobility and acceptor density in hole transport materials were identified to significantly influence the performance of the device. Strikingly, an efficiency over 20% was obtained under the moderate simulation conditions.

  4. Efficiency calculations of thin-film GaAs solar cells on Si substrates

    SciTech Connect (OSTI)

    Yamaguchi, M.; Amano, C.

    1985-11-01

    Dislocation effect upon the efficiency of single-crystal thin-film AlGaAs-GaAs heteroface solar cells on Si substrates is analyzed. Solar-cell properties are calculated based on a simple model; in the model, dislocations act as recombination centers to reduce the minority-carrier diffusion length in each layer and increase the space-charge layer recombination current. Numerical analysis is also carried out to optimize thin-film AlGaAs-GaAs heteroface solar-cell structures. The fabrication of thin-film AlGaAs-GaAs heteroface solar cells with a practical efficiency larger than 18% on Si substrates appears possible if the dislocation density in the thin-film GaAs layer is less than 10/sup 6/ cm/sup -2/.

  5. Efficiency considerations for polycrystalline GaAs thin-film solar cells

    SciTech Connect (OSTI)

    Yamaguchi, M.; Itoh, Y.

    1986-07-01

    The effect of grain boundaries upon the efficiency of polycrystalline GaAs thin-film solar cells is analyzed. Solar-cell properties are calculated on a simple model where grain boundaries act as recombination centers to reduce the minority-carrier diffusion length in the solar cell's active layer and increase the space-charge layer recombination current. An effective diffusion length is expressed in terms of grain size, allowing the calculation of short-circuit current density and open-circuit voltage. Excellent agreement is obtained between theory and experiment. The fabrication of thin-film GaAs solar cells with an efficiency greater than 18% appears to be possible if the grain size in the thin-film GaAs layer with thickness of 3 ..mu..m is larger than 1000 ..mu..m.

  6. Thin film GaAs solar cells on glass substrates by epitaxial liftoff

    SciTech Connect (OSTI)

    Lee, X.Y.; Goertemiller, M.; Boroditsky, M.; Ragan, R.; Yablonovitch, E.

    1997-02-01

    In this work, we describe the fabrication and operating characteristics of GaAs/AlGaAs thin film solar cells processed by the epitaxial liftoff (ELO) technique. This technique allows the transfer of these cells onto glass substrates. The performance of the lifted-off solar cell is demonstrated by means of electrical measurements under both dark and illuminated conditions. We have also optimized the light trapping conditions in this direct-gap material. The results show that good solar absorption is possible in active layers as thin as 0.32 {mu}m. In such a thin solar cell, the open circuit voltage would be enhanced. We believe that the combination of an epitaxial liftoff thin GaAs film, and nano-texturing can lead to record breaking performance. {copyright} {ital 1997 American Institute of Physics.}

  7. NREL Invention Speeds Solar Cell Quality Testing for Industry (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-08-01

    A solid-state optical system, invented by the National Renewable Energy Laboratory (NREL), measures solar cell quantum efficiency (QE) in less than a second, enabling a suite of new capabilities for solar cell manufacturers. QE is a measurement of how cells respond to light across the solar spectrum, but traditional methods for measuring QE had been too slow, limiting its application to small samples pulled from the production line and analyzed in laboratories. NREL's technique, commercialized by Tau Science as the FlashQE(TM) system, uses a solid-state light source, synchronized electronics, and advanced mathematical analysis to parallel-process QE data in a tiny fraction of the time required by the current method, allowing its use on every solar cell passing through a production line.

  8. Barrier Coatings for Thin Film Solar Cells: Final Subcontract Report, September 1, 2002 -- January 30, 2008

    SciTech Connect (OSTI)

    Olsen, L. C.

    2010-03-01

    This program has involved investigations of the stability of CdTe and copper-indium-gallium-diselenide (CIGS) solar cells under damp heat conditions and effects of barrier coatings.

  9. Earth-abundant Solar Cells: Can Iron Complexes Serve as Photosensitize...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Earth-abundant Solar Cells: Can Iron Complexes Serve as Photosensitizers in DSSCs November 10, 2015 11:00AM to 12:00PM Presenter Elena Jakubikova, North Carolina State University...

  10. NREL's Optical Cavity Furnace Brings Together a Myriad of Advances for Processing Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-08-01

    Fact sheet on 2011 R&D 100 Award winner, the Optical Cavity Furnace. The innovative furnace uses light and unique light-induced effects to make higher-efficiency solar cells at lower cost.

  11. CIGS Thin-Film Solar Cell Research at NREL: FY04 Results and...

    Office of Scientific and Technical Information (OSTI)

    the latter were used for the bulk of the process development work, and a 14.4%-efficient solar cell was fabricated. The deposition method is new and offers some advantages over...

  12. Enhanced conversion efficiency in wide-bandgap GaNP solar cells...

    Office of Scientific and Technical Information (OSTI)

    Enhanced conversion efficiency in wide-bandgap GaNP solar cells Citation Details In-Document Search This content will become publicly available on October 12, 2016 Title: Enhanced...

  13. Toward Improved Hybrid Solar Cells (IN-07-053) - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Patent Applications ID Number Title and Abstract Primary Lab Date Patent 8,269,100 Patent 8,269,100 Hybrid solar cells via UV-polymerization of polymer precursor A hybrid...

  14. High Efficiency CdTe Ink-Based Solar Cells Using Nanocrystals (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2015-01-01

    This NREL Highlight is being developed for the 2015 February Alliance S&T Board meeting and describes a solution-processable ink to produce high-efficiency solar cells using low temperature and simple processing.

  15. Light-Biasing Electron-Beam-Induced-Current Measurements for Multijunction Solar Cells: Preprint

    SciTech Connect (OSTI)

    Romero, M. J.; Olson, J. M.; Al-Jassim, M. M.

    2001-10-01

    Presented at the 2001 NCPV Program Review Meeting: Results using light-biasing EBIC are illustrated for dual-junction InGaP/InGaAs solar cells.

  16. Eco-friendly Battery and Solar Cell All-in-One | U.S. DOE Office...

    Office of Science (SC) Website

    Eco-friendly Battery and Solar Cell All-in-One Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy ...

  17. Light trapping in thin film solar cells using textured photonic crystal

    DOE Patents [OSTI]

    Yi, Yasha (Somerville, MA); Kimerling, Lionel C. (Concord, MA); Duan, Xiaoman (Amesbury, MA); Zeng, Lirong (Cambridge, MA)

    2009-01-27

    A solar cell includes a photoactive region that receives light. A photonic crystal is coupled to the photoactive region, wherein the photonic crystal comprises a distributed Bragg reflector (DBR) for trapping the light.

  18. Materials en Multi-junction Solar Cells to Push CPV Efficiencies...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ceem.ucsb.edurss News and Events - Center for Energy Efficient Materials en Multi-junction Solar Cells to Push CPV Efficiencies Beyond 50% http:www.compoundsemiconductor.net...

  19. Student Winners Announced in Solar, Hydrogen and Lithium Ion Fuel Cell Car

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Races - News Releases | NREL Student Winners Announced in Solar, Hydrogen and Lithium Ion Fuel Cell Car Races May 12, 2012 One hundred four teams from 23 Colorado schools participated in today's car competitions hosted by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL). The student teams raced solar, lithium ion, or hydrogen fuel cell powered vehicles they designed and built themselves. Trophies for the fastest lithium-ion powered model cars were given to Colorado

  20. Single-junction solar cells with the optimum band gap for terrestrial concentrator applications

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO)

    1994-01-01

    A single-junction solar cell having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown that the presence of absorption bands in the direct spectrum has the effect of "pinning" the optimum band gap for a wide range of operating conditions at a value of 1.14.+-.0.02 eV. Efficiencies exceeding 30% may be possible at high concentration ratios for devices with the ideal band gap.