A modular molecular framework for utility in small-molecule solution-processed organic photovoltaic devices

Journal Article · Fri Jul 22 00:00:00 EDT 2011 · Journal of Materials Chemistry

DOI:https://doi.org/10.1039/C1JM11963J· OSTI ID:1065739

Welch, Gregory C. ^[1]; Perez, Louis A. ^[2]; Hoven, Corey V. ^[1]; Zhang, Yuan ^[1]; Dang, Xuan-Dung ^[1]; Sharenko, Alexander ^[2]; Toney, Michael F. ^[3]; Kramer, Edward J. ^[4]; Nguyen, Thuc-Quyen ^[5]; Bazan, Guillermo C. ^[6]

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1. Univ. of California, Santa Barbara, CA (United States). Center for Energy Efficient Materials
2. Univ. of California, Santa Barbara, CA (United States). Center for Energy Efficient Materials and Dept. of Materials
3. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)
4. Univ. of California, Santa Barbara, CA (United States). Dept. of Chemical Engineering and Dept. of Materials
5. Univ. of California, Santa Barbara, CA (United States). Center for Energy Efficient Materials, Center for Polymers and Organic Solids and Dept. of Chemistry & Biochemistry
6. Univ. of California, Santa Barbara, CA (United States). Center for Energy Efficient Materials, Center for Polymers and Organic Solids, Dept. of Chemistry & Biochemistry and Dept. of Materials

We report on the design, synthesis and characterization of light harvesting small molecules for use in solution-processed small molecule bulk heterojunction (SM-BHJ) solar cell devices. These molecular materials are based upon an acceptor/donor/acceptor (A/D/A) core with donor endcapping units. Utilization of a dithieno(3,2-b;2',3'-d)silole (DTS) donor and pyridal[2,1,3]thiadiazole (PT) acceptor leads to strong charge transfer characteristics, resulting in broad optical absorption spectra extending well beyond 700 nm. SM-BHJ solar cell devices fabricated with the specific example 5,5'-bis{7-(4-(5-hexylthiophen-2-yl)thiophen-2-yl)-[1,2,5]thiadiazolo[3,4-c]pyridine}-3,3'-di-2-ethylhexylsilylene-2,2'-bithiophene (6) as the donor and [6,6]-phenyl-C₇₁-butyric acid methyl ester (PC₇₁BM) as the acceptor component showed short circuit currents above -10 mA cm^-2 and power conversion efficiencies (PCEs) over 3%. Thermal processing is a critical factor in obtaining favorable active layer morphologies and high PCE values. A combination of UV-visible spectroscopy, conductive and photo-conductive atomic force microscopies, dynamic secondary mass ion spectrometry (DSIMS), and grazing incident wide angle X-ray scattering (GIWAXS) experiments were carried out to characterize how thermal treatment influences the active layer structure and organization.

• Research Organization: Energy Frontier Research Centers (EFRC) (United States). Center for Energy Efficient Materials (CEEM)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• DOE Contract Number: SC0001009
• OSTI ID: 1065739
• Journal Information: Journal of Materials Chemistry, Vol. 21, Issue 34; Related Information: CEEM partners with the University of California, Santa Barbara (lead); Purdue University; Los Alamos National Laboratory; National Renewable Energy Laboratory; ISSN 0959-9428: JMACEP
• Publisher: Royal Society of Chemistry
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
solar (photovoltaic)
solid state lighting
phonons
thermoelectric
bio-inspired
energy storage (including batteries and capacitors)
electrodes - solar
defects
charge transport
materials and chemistry by design
optics
synthesis (novel materials)
synthesis (self-assembly)
synthesis (scalable processing)