National Library of Energy BETA

Sample records for materials synthesis self-assembly

  1. Self-assembly of nanocomposite materials

    DOE Patents [OSTI]

    Brinker, C. Jeffrey (Albuquerque, NM); Sellinger, Alan (Palo Alto, CA); Lu, Yunfeng (New Orleans, LA)

    2001-01-01

    A method of making a nanocomposite self-assembly is provided where at least one hydrophilic compound, at least one hydrophobic compound, and at least one amphiphilic surfactant are mixed in an aqueous solvent with the solvent subsequently evaporated to form a self-assembled liquid crystalline mesophase material. Upon polymerization of the hydrophilic and hydrophobic compounds, a robust nanocomposite self-assembled material is formed. Importantly, in the reaction mixture, the amphiphilic surfactant has an initial concentration below the critical micelle concentration to allow formation of the liquid-phase micellar mesophase material. A variety of nanocomposite structures can be formed, depending upon the solvent evaporazation process, including layered mesophases, tubular mesophases, and a hierarchical composite coating composed of an isotropic worm-like micellar overlayer bonded to an oriented, nanolaminated underlayer.

  2. Self-assembled lipid bilayer materials

    DOE Patents [OSTI]

    Sasaki, Darryl Y.; Waggoner, Tina A.; Last, Julie A.

    2005-11-08

    The present invention is a self-assembling material comprised of stacks of lipid bilayers formed in a columnar structure, where the assembly process is mediated and regulated by chemical recognition events. The material, through the chemical recognition interactions, has a self-regulating system that corrects the radial size of the assembly creating a uniform diameter throughout most of the structure. The materials form and are stable in aqueous solution. These materials are useful as structural elements for the architecture of materials and components in nanotechnology, efficient light harvesting systems for optical sensing, chemical processing centers, and drug delivery vehicles.

  3. Biocompatible self-assembly of nano-materials for Bio-MEMS and insect reconnaissance.

    SciTech Connect (OSTI)

    Brozik, Susan Marie; Cesarano, Joseph, III; Brinker, C. Jeffrey; Dunphy, Darren Robert; Sinclair, Michael B.; Manginell, Monica; Ashley, Carlee E.; Timlin, Jerilyn Ann; Werner-Washburne, Margaret C.; Calvert, Paul Davidson; Hartenberger, Tamara N.; Flemming, Jeb Hunter; Baca, Helen Kennicott

    2003-12-01

    This report summarizes the development of new biocompatible self-assembly procedures enabling the immobilization of genetically engineered cells in a compact, self-sustaining, remotely addressable sensor platform. We used evaporation induced self-assembly (EISA) to immobilize cells within periodic silica nanostructures, characterized by unimodal pore sizes and pore connectivity, that can be patterned using ink-jet printing or photo patterning. We constructed cell lines for the expression of fluorescent proteins and induced reporter protein expression in immobilized cells. We investigated the role of the abiotic/biotic interface during cell-mediated self-assembly of synthetic materials.

  4. Synthesis and Characterization of Stimuli Responsive Block Copolymers, Self-Assembly Behavior and Applications

    SciTech Connect (OSTI)

    Michael Duane Determan

    2005-12-17

    The central theme of this thesis work is to develop new block copolymer materials for biomedical applications. While there are many reports of stimuli-responsive amphiphilic [19-21] and crosslinked hydrogel materials [22], the development of an in situ gel forming, pH responsive pentablock copolymer is a novel contribution to the field, Figure 1.1 is a sketch of an ABCBA pentablock copolymer. The A blocks are cationic tertiary amine methacrylates blocked to a central Pluronic F127 triblock copolymer. In addition to the prerequisite synthetic and macromolecular characterization of these new materials, the self-assembled supramolecular structures formed by the pentablock were experimentally evaluated. This synthesis and characterization process serves to elucidate the important structure property relationships of these novel materials, The pH and temperature responsive behavior of the pentablock copolymer were explored especially with consideration towards injectable drug delivery applications. Future synthesis work will focus on enhancing and tuning the cell specific targeting of DNA/pentablock copolymer polyplexes. The specific goals of this research are: (1) Develop a synthetic route for gel forming pentablock block copolymers with pH and temperature sensitive properties. Synthesis of these novel copolymers is accomplished with ATRP, yielding low polydispersity and control of the block copolymer architecture. Well defined macromolecular characteristics are required to tailor the phase behavior of these materials. (2) Characterize relationship between the size and shape of pentablock copolymer micelles and gel structure and the pH and temperature of the copolymer solutions with SAXS, SANS and CryoTEM. (3) Evaluate the temperature and pH induced phase separation and macroscopic self-assembly phenomenon of the pentablock copolymer. (4) Utilize the knowledge gained from first three goals to design and formulate drug delivery formulations based on the multi

  5. Controlled synthesis of snowflake-like self-assemblies palladium nanostructures under microwave irradiation

    SciTech Connect (OSTI)

    Xie, Ting; Ma, Yue; Yang, Hanmin Li, Jinlin

    2013-08-01

    Graphical abstract: - Highlights: We demonstrated the synthesis of snowflake-like palladium nanostructures for the first time. We discussed the influencing factors on the synthesis of snowflake-like Pd nanostructures. The molar ratio of H{sub 2}Pd{sub 4} to PVP at 5 is the optimal selection. The growth process was discussed. - Abstract: Self-assembly snowflake-like palladium nanostructures were synthesized under microwave irradiation using H{sub 2}PdCl{sub 4} as precursor, benzyl alcohol as both solvent and reducing agent, and PVP as stabilizer. The Pd snowflake-like nanostructures were formed and then characterized by transmission electron microscopy (TEM) and X-ray powder diffraction. The TEM images showed that the Pd nano-snowflakes were self-assemblies organized by hundreds of small spherical nanoparticles. Pd snowflake-like nanostructures with well-defined shape and uniform size can be obtained by tuning the concentration of palladium precursor, the molar ratio of H{sub 2}PdCl{sub 4}/PVP, as well as the heating time by microwave irradiation. The possible growing process of the snowflake-like Pd structures was also proposed on the basis of investigating the properties of as-synthesized Pd nanostructures under different conditions.

  6. Self-assembled photosynthesis-inspired light harvesting material and solar cells containing the same

    DOE Patents [OSTI]

    Lindsey, Jonathan S.; Chinnasamy, Muthiah; Fan, Dazhong

    2009-12-15

    A solar cell is described that comprises: (a) a semiconductor charge separation material; (b) at least one electrode connected to the charge separation material; and (c) a light-harvesting film on the charge separation material, the light-harvesting film comprising non-covalently coupled, self-assembled units of porphyrinic macrocycles. The porphyrinic macrocycles preferably comprise: (i) an intramolecularly coordinated metal; (ii) a first coordinating substituent; and (iii) a second coordinating substituent opposite the first coordinating substituent. The porphyrinic macrocycles can be assembled by repeating intermolecular coordination complexes of the metal, the first coordinating substituent and the second coordinating substituent.

  7. Polar self-assembled thin films for non-linear optical materials

    DOE Patents [OSTI]

    Yang, XiaoGuang; Swanson, Basil I.; Li, DeQuan

    2000-01-01

    The design and synthesis of a family of calix[4]arene-based nonlinear optical (NLO) chromophores are discussed. The calixarene chromophores are macrocyclic compounds consisting of four simple D-.pi.-A units bridged by methylene groups. These molecules were synthesized such that four D-.pi.-A units of the calix[4]arene were aligned along the same direction with the calixarene in a cone conformation. These nonlinear optical super-chromophores were subsequently fabricated into covalently bound self-assembled monolayers on the surfaces of fused silica and silicon. Spectroscopic second harmonic generation (SHG) measurements were carried out to determine the absolute value of the dominant element of the second-order nonlinear susceptibility, d.sub.33, and the average molecular alignment, .PSI.. A value of d.sub.33 =60 pm/V at a fundamental wavelength of 890 nm, and .PSI..about.36.degree. was found with respect to the surface normal.

  8. De novo synthesis and properties of analogues of the self-assembling chlorosomal bacteriochlorophylls

    SciTech Connect (OSTI)

    Mass, Olga [North Carolina State Univ., Raleigh, NC (United States); Pandithavidana, Dinesh R. [North Carolina State Univ., Raleigh, NC (United States); Ptaszek, Marcin [North Carolina State Univ., Raleigh, NC (United States); Santiago, Koraliz [North Carolina State Univ., Raleigh, NC (United States); Springer, Joseph W. [Washington Univ., St. Louis, MO (United States); Jiao, Jieying [Univ. Of California, Riverside, CA (United States); Tang, Qun [Univ. Of California, Riverside, CA (United States); Kirmaier, Christine [Washington Univ., St. Louis, MO (United States); Bocian, David F. [Univ. Of California, Riverside, CA (United States); Holten, Dewey [Washington Univ., St. Louis, MO (United States); Lindsey, Jonathan S. [North Carolina State Univ., Raleigh, NC (United States)

    2011-01-01

    Natural photosynthetic pigments bacteriochlorophyllsc, d and e in green bacteria undergo self-assembly to create an organized antenna system known as the chlorosome, which collects photons and funnels the resulting excitation energy toward the reaction centers. Mimicry of chlorosome function is a central problem in supramolecular chemistry and artificial photosynthesis, and may have relevance for the design of photosynthesis-inspired solar cells. The main challenge in preparing artificial chlorosomes remains the synthesis of the appropriate pigment (chlorin) equipped with a set of functional groups suitable to direct the assembly and assure efficient energy transfer. Prior approaches have entailed derivatization of porphyrins or semisynthesis beginning with chlorophylls. This paper reports a third approach, the de novo synthesis of macrocycles that contain the same hydrocarbon skeleton as chlorosomal bacteriochlorophylls. The synthesis here of Zn(II) 3-(1-hydroxyethyl)-10-aryl-13-oxophorbines (the aryl group consists of phenyl, mesityl, or pentafluorophenyl) entails selective bromination of a 3,13-diacetyl-10-arylchlorin, palladium-catalyzed 13-oxophorbine formation, and selective reduction of the 3-acetyl group using BH?tBuNH?. Each macrocycle contains a geminal dimethyl group in the pyrroline ring to provide stability toward adventitious dehydrogenation. A Zn(II) 7-(1-hydroxyethyl)-10-phenyl-17-oxochlorin also has been prepared. Altogether, 30 new hydroporphyrins were synthesized. The UV-Vis absorption spectra of the new chlorosomal bacteriochlorophyll mimics reveal a bathochromic shift of [similar]1800 cm-1 of the Qy band in nonpolar solvent, indicating extensive assembly in solution. The Zn(II) 3-(1-hydroxyethyl)-10-aryl-13-oxophorbines differ in the propensity to form assemblies based on the 10-substituent in the following order: mesityl

  9. Self-assembled peptide nanotubes as electronic materials: An evaluation from first-principles calculations

    SciTech Connect (OSTI)

    Akdim, Brahim E-mail: ruth.pachter@us.af.mil; Pachter, Ruth E-mail: ruth.pachter@us.af.mil; Naik, Rajesh R.

    2015-05-04

    In this letter, we report on the evaluation of diphenylalanine (FF), dityrosine (YY), and phenylalanine-tryptophan (FW) self-assembled peptide nanotube structures for electronics and photonics applications. Realistic bulk peptide nanotube material models were used in density functional theory calculations to mimic the well-ordered tubular nanostructures. Importantly, validated functionals were applied, specifically by using a London dispersion correction to model intertube interactions and a range-separated hybrid functional for accurate bandgap calculations. Bandgaps were found consistent with available experimental data for FF, and also corroborate the higher conductance reported for FW in comparison to FF peptide nanotubes. Interestingly, the predicted bandgap for the YY tubular nanostructure was found to be slightly higher than that of FW, suggesting higher conductance as well. In addition, the band structure calculations along the high symmetry line of nanotube axis revealed a direct bandgap for FF. The results enhance our understanding of the electronic properties of these material systems and will pave the way into their application in devices.

  10. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly...

  11. Photovoltaic self-assembly.

    SciTech Connect (OSTI)

    Lavin, Judith; Kemp, Richard Alan; Stewart, Constantine A.

    2010-10-01

    This late-start LDRD was focused on the application of chemical principles of self-assembly on the ordering and placement of photovoltaic cells in a module. The drive for this chemical-based self-assembly stems from the escalating prices in the 'pick-and-place' technology currently used in the MEMS industries as the size of chips decreases. The chemical self-assembly principles are well-known on a molecular scale in other material science systems but to date had not been applied to the assembly of cells in a photovoltaic array or module. We explored several types of chemical-based self-assembly techniques, including gold-thiol interactions, liquid polymer binding, and hydrophobic-hydrophilic interactions designed to array both Si and GaAs PV chips onto a substrate. Additional research was focused on the modification of PV cells in an effort to gain control over the facial directionality of the cells in a solvent-based environment. Despite being a small footprint research project worked on for only a short time, the technical results and scientific accomplishments were significant and could prove to be enabling technology in the disruptive advancement of the microelectronic photovoltaics industry.

  12. Confined cooperative self-assembly and synthesis of optically and electrically active nanostructures : final LDRD report

    SciTech Connect (OSTI)

    Coker, Eric Nicholas; Haddad, Raid Edward; Fan, Hongyou; Ta, Anh; Bai, Feng; Rodriguez, Mark Andrew; Huang, Jian Yu

    2011-10-01

    In this project, we developed a confined cooperative self-assembly process to synthesize one-dimensional (1D) j-aggregates including nanowires and nanorods with controlled diameters and aspect ratios. The facile and versatile aqueous solution process assimilates photo-active macrocyclic building blocks inside surfactant micelles, forming stable single-crystalline high surface area nanoporous frameworks with well-defined external morphology defined by the building block packing. Characterizations using TEM, SEM, XRD, N{sub 2} and NO sorption isotherms, TGA, UV-vis spectroscopy, and fluorescence imaging and spectroscopy indicate that the j-aggregate nanostructures are monodisperse and may further assemble into hierarchical arrays with multi-modal functional pores. The nanostructures exhibit enhanced and collective optical properties over the individual chromophores. This project was a small footprint research effort which, nonetheless, produced significant progress towards both the stated goal as well as unanticipated research directions.

  13. Synthesis and characteristic of self-assembled diamond/copper nanocomposites

    SciTech Connect (OSTI)

    Shi Xiaoqn; Jiang Xiaohong Lu Lude; Yang Xujie; Wang Xin

    2008-11-03

    Nanodiamond (ND) supported metal oxide or metal catalysts exhibit excellent catalytic activity. ND/Cu nanocomposites and Cu nanoparticles were prepared by reducing Cu(NO{sub 3}){sub 2} in reverses micelle solution. Products were analyzed by X-ray diffraction (XRD), electron paramagnetic resonance (EPR) spectra, UV-vis optical characteristic and transmission electron microscopy (TEM). From the point of nucleation and grow of crystal, ND contributed to heterogeneous nucleation of Cu nanocrystal. The reactive mechanism was explored based on theory of free energy. The formation of resultant self-assembled structures was explained through diffusion-limited aggregation model and Marangoni effect. Both Cu and ND/Cu nanoparticles were strong catalysts on decomposition of NH{sub 4}ClO{sub 4} (AP), and ND/Cu is more effective.

  14. "Plastic" Solar Cells: Self-Assembly of Bulk HeterojunctionNano...

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

    Self-Assembly of Bulk Heterojunction Nano-Materials by Spontaneous Phase Separation ... self-assembly of bulk heterojunction (BHJ) nano-materials by spontaneous phase separation. ...

  15. Self assembled molecular monolayers on high surface area materials as molecular getters

    DOE Patents [OSTI]

    King, D.E.; Herdt, G.C.; Czanderna, A.W.

    1997-01-07

    The present invention relates to a gettering material that may be used as a filtration medium to remove pollutants from the environment. The gettering material comprises a high surface area material having a metal surface that chemically bonds n-alkanethiols in an organized manner thereby forming a molecular monolayer over the metal surface. The n-alkanethiols have a free functional group that interacts with the environment thereby binding specific pollutants that may be present. The gettering material may be exposed to streams of air in heating, ventilation, and air conditioning systems or streams of water to remove specific pollutants from either medium. 9 figs.

  16. Self assembled molecular monolayers on high surface area materials as molecular getters

    DOE Patents [OSTI]

    King, David E.; Herdt, Gregory C.; Czanderna, Alvin W.

    1997-01-01

    The present invention relates to a gettering material that may be used as a filtration medium to remove pollutants from the environment. The gettering material comprises a high surface area material having a metal surface that chemically bonds n-alkanethiols in an organized manner thereby forming a molecular monolayer over the metal surface. The n-alkanethiols have a free functional group that interacts with the environment thereby binding specific pollutants that may be present. The gettering material may be exposed to streams of air in heating, ventilation, and air conditioning systems or streams of water to remove specific pollutants from either medium.

  17. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    SciTech Connect (OSTI)

    Liu, Jun; Aksay, Ilhan A; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2015-04-28

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  18. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2014-09-16

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  19. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2013-10-22

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  20. Palladium catalyzed reactions executed on solid-phase peptide synthesis supports for the production of self-assembling peptides embedded with complex organic electronic subunits

    DOE Patents [OSTI]

    Tovar, John D.; Sanders, Allix M.

    2016-01-12

    Methods to synthesize self-assembling peptides embedded with complex organic electronic subunits are provided.

  1. Palladium catalyzed reactions executed on solid-phase peptide synthesis supports for the production of self-assembling peptides embedded with complex organic electronic subunits

    DOE Patents [OSTI]

    Tovar, John D; Sanders, Allix M

    2014-10-28

    Methods to synthesize self-assembling peptides embedded with complex organic electronic subunits are provided.

  2. Ordered porous mesostructured materials from nanoparticle-block copolymer self-assembly

    DOE Patents [OSTI]

    Warren, Scott; Wiesner, Ulrich; DiSalvo, Jr., Francis J

    2013-10-29

    The invention provides mesostructured materials and methods of preparing mesostructured materials including metal-rich mesostructured nanoparticle-block copolymer hybrids, porous metal-nonmetal nanocomposite mesostructures, and ordered metal mesostructures with uniform pores. The nanoparticles can be metal, metal alloy, metal mixture, intermetallic, metal-carbon, metal-ceramic, semiconductor-carbon, semiconductor-ceramic, insulator-carbon or insulator-ceramic nanoparticles, or combinations thereof. A block copolymer/ligand-stabilized nanoparticle solution is cast, resulting in the formation of a metal-rich (or semiconductor-rich or insulator-rich) mesostructured nanoparticle-block copolymer hybrid. The hybrid is heated to an elevated temperature, resulting in the formation of an ordered porous nanocomposite mesostructure. A nonmetal component (e.g., carbon or ceramic) is then removed to produce an ordered mesostructure with ordered and large uniform pores.

  3. Molecular Self-Assembly

    SciTech Connect (OSTI)

    CURRO, JOHN G.; MCCOY, JOHN DWANE; FRISCHKNECHT, AMALIE L.; YU, KUI

    2001-11-01

    This report is divided into two parts: a study of the glass transition in confined geometries, and formation mechanisms of block copolymer mesophases by solvent evaporation-induced self-assembly. The effect of geometrical confinement on the glass transition of polymers is a very important consideration for applications of polymers in nanotechnology applications. We hypothesize that the shift of the glass transition temperature of polymers in confined geometries can be attributed to the inhomogeneous density profile of the liquid. Accordingly, we assume that the glass temperature in the inhomogeneous state can be approximated by the Tg of a corresponding homogeneous, bulk polymer, but at a density equal to the average density of the inhomogeneous system. Simple models based on this hypothesis give results that are in remarkable agreement with experimental measurements of the glass transition of confined liquids. Evaporation-induced self-assembly (EISA) of block copolymers is a versatile process for producing novel, nanostructured materials and is the focus of much of the experimental work at Sandia in the Brinker group. In the EISA process, as the solvent preferentially evaporates from a cast film, two possible scenarios can occur: microphase separation or micellization of the block copolymers in solution. In the present investigation, we established the conditions that dictate which scenario takes place. Our approach makes use of scaling arguments to determine whether the overlap concentration c* occurs before or after the critical micelle concentration (CMC). These theoretical arguments are used to interpret recent experimental results of Yu and collaborators on EISA experiments on Silica/PS-PEO systems.

  4. Electronic & Magnetic Materials & Devices Capabilities | Argonne...

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

    Electronic & Magnetic Materials & Devices Capabilities Synthesis Colloidal chemistry and self-assembly techniques Complex oxide film synthesis via molecular beam epitaxy (DCA R450...

  5. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Self-Assembly of Polymer Nano-Elements on Sapphire Print Wednesday, 25 March 2009 00:00 Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned

  6. Self assembling proteins

    DOE Patents [OSTI]

    Yeates, Todd O.; Padilla, Jennifer; Colovos, Chris

    2004-06-29

    Novel fusion proteins capable of self-assembling into regular structures, as well as nucleic acids encoding the same, are provided. The subject fusion proteins comprise at least two oligomerization domains rigidly linked together, e.g. through an alpha helical linking group. Also provided are regular structures comprising a plurality of self-assembled fusion proteins of the subject invention, and methods for producing the same. The subject fusion proteins find use in the preparation of a variety of nanostructures, where such structures include: cages, shells, double-layer rings, two-dimensional layers, three-dimensional crystals, filaments, and tubes.

  7. Synthesis of novel 3D SnO flower-like hierarchical architectures self-assembled by nano-leaves and its photocatalysis

    SciTech Connect (OSTI)

    Cui, Yongkui; Wang, Fengping Iqbal, M. Zubair; Wang, Ziya; Li, Yan; Tu, Jianhai

    2015-10-15

    Highlights: • Novel 3D SnO flowers self-assembled by 2D nano-leaves were synthesized by hydrothermal method. • The SnO nano-leaf is of single crystalline nature. • The band gap of 2.59 eV of as-prepared products was obtained. • The as-synthesized material will be a promising photocatalytic material. - Abstract: In this report, the novel 3D SnO flower-like hierarchical architectures self-assembled by 2D SnO nano-leaves are successfully synthesized via template-free hydrothermal approach under facile conditions. The high-resolution transmission electron microscopy results demonstrate that the 2D nano-leaves structure is of single crystalline nature. The band gap 2.59 eV for prepared product is obtained from UV–vis diffuse reflectance spectrum. The photocatalysis of the as prepared SnO for degrading methyl orange (MO) has been studied. A good photocatalytic activity is obtained and the mechanism is discussed in detail. Results indicate that the SnO nanostructures are the potential candidates for photocatalyst applications.

  8. Directed Self-Assembly of Nanodispersions

    SciTech Connect (OSTI)

    Furst, Eric M

    2013-11-15

    Directed self-assembly promises to be the technologically and economically optimal approach to industrial-scale nanotechnology, and will enable the realization of inexpensive, reproducible and active nanostructured materials with tailored photonic, transport and mechanical properties. These new nanomaterials will play a critical role in meeting the 21st century grand challenges of the US, including energy diversity and sustainability, national security and economic competitiveness. The goal of this work was to develop and fundamentally validate methods of directed selfassembly of nanomaterials and nanodispersion processing. The specific aims were: 1. Nanocolloid self-assembly and interactions in AC electric fields. In an effort to reduce the particle sizes used in AC electric field self-assembly to lengthscales, we propose detailed characterizations of field-driven structures and studies of the fundamental underlying particle interactions. We will utilize microscopy and light scattering to assess order-disorder transitions and self-assembled structures under a variety of field and physicochemical conditions. Optical trapping will be used to measure particle interactions. These experiments will be synergetic with calculations of the particle polarizability, enabling us to both validate interactions and predict the order-disorder transition for nanocolloids. 2. Assembly of anisotropic nanocolloids. Particle shape has profound effects on structure and flow behavior of dispersions, and greatly complicates their processing and self-assembly. The methods developed to study the self-assembled structures and underlying particle interactions for dispersions of isotropic nanocolloids will be extended to systems composed of anisotropic particles. This report reviews several key advances that have been made during this project, including, (1) advances in the measurement of particle polarization mechanisms underlying field-directed self-assembly, and (2) progress in the

  9. Transport and Self-Assembly in Molecular Nanosystems

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

    Transport and Self-Assembly in Molecular Nanosystems Key Challenges: Use classical molecular dynamics and coarse grain molecular dynamics to enable "bottom-up" material...

  10. Synthesis of carbon nanotube/anatase titania composites by a combination of sol-gel and self-assembly at low temperature

    SciTech Connect (OSTI)

    Hu Changyuan; Zhang Rongfa; Xiang Junhuai; Liu Tingzhi; Li Wenkui; Li Mingsheng; Duo Shuwang; Wei Fei

    2011-05-15

    A simple method is described for the synthesis of carbon nanotube/anatase titania composites by a combination of a sol-gel method with a self-assembly technique at 65 {sup o}C. This method makes use of polyelectrolyte for wrapping multi-walled carbon nanotube (MWCNT) and providing them with adsorption sites for electrostatically driven TiO{sub 2} nanoparticle deposition. The composites were characterized using X-ray diffraction, transmission electron microscopy, Fourier transform infrared and X-ray photoelectron spectroscopy, and photoluminescence for analyzing their crystal phase, microstructure, particle size, and other physicochemical properties. The results showed that MWCNT were covered with an anatase TiO{sub 2} thin layer or surrounded by an anatase TiO{sub 2} thick coating, which is constructed of TiO{sub 2} particles about 6 nm in size. The composites were rich in surface hydroxyl groups. The excited e{sup -} in conduction band of TiO{sub 2} may migrate to MWCNT. Concerning the potential applicability, MWCNT/TiO{sub 2} composites showed excellent photocatalytic activity toward the photodegradation of methyl orange. -- Graphical abstract: MWCNT/anatase TiO{sub 2} composites have been prepared by a combination of a sol-gel method and a self-assembly technique in one step at low temperature without high temperature calcination. Display Omitted Highlights: {yields} MWCNT/anatase TiO{sub 2} composites could be prepared in one-pot at low temperature. {yields} MWCNT were covered with a TiO{sub 2} thin layer or surrounded by a TiO{sub 2} thick coating. {yields} Composites were rich in surface hydroxyl groups. {yields} Composites showed excellent photodegradation activity of methyl orange.

  11. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned arrays have been produced using electron-beam lithographic techniques or

  12. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned arrays have been produced using electron-beam lithographic techniques or

  13. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned arrays have been produced using electron-beam lithographic techniques or

  14. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned arrays have been produced using electron-beam lithographic techniques or

  15. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned arrays have been produced using electron-beam lithographic techniques or

  16. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned arrays have been produced using electron-beam lithographic techniques or

  17. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured materials, since self-assembly is highly parallel, quite versatile, and easy to implement. Especially promising are novel compounds known as block copolymers, formed by two chemically different polymers that are linked together. Guided patterned arrays have been produced using electron-beam lithographic techniques or

  18. GeSi strained nanostructure self-assembly for nano- and opto...

    Office of Scientific and Technical Information (OSTI)

    Strain-induced self-assembly during semiconductor heteroepitaxy offers a promising ... DOTS; QUANTUM WIRES Optoelectronic devices.; Nanostructure materials.; ...

  19. Self-assembled nanolaminate coatings (SV)

    SciTech Connect (OSTI)

    Fan, H.

    2012-03-01

    Sandia National Laboratories (Sandia) and Lockheed Martin Aeronautics (LM Aero) are collaborating to develop affordable, self-assembled, nanocomposite coatings and associated fabrication processes that will be tailored to Lockheed Martin product requirements. The purpose of this project is to develop a family of self-assembled coatings with properties tailored to specific performance requirements, such as antireflective (AR) optics, using Sandia-developed self-assembled techniques. The project met its objectives by development of a simple and economic self-assembly processes to fabricate multifunctional coatings. Specifically, materials, functionalization methods, and associated coating processes for single layer and multiple layers coatings have been developed to accomplish high reflective coatings, hydrophobic coatings, and anti-reflective coatings. Associated modeling and simulations have been developed to guide the coating designs for optimum optical performance. The accomplishments result in significant advantages of reduced costs, increased manufacturing freedom/producibility, improved logistics, and the incorporation of new technology solutions not possible with conventional technologies. These self-assembled coatings with tailored properties will significantly address LMC's needs and give LMC a significant competitive lead in new engineered materials. This work complements SNL's LDRD and BES programs aimed at developing multifunctional nanomaterials for microelectronics and optics as well as structure/property investigations of self-assembled nanomaterials. In addition, this project will provide SNL with new opportunities to develop and apply self-assembled nanocomposite optical coatings for use in the wavelength ranges of 3-5 and 8-12 micrometers, ranges of vital importance to military-based sensors and weapons. The SANC technologies will be applied to multiple programs within the LM Company including the F-35, F-22, ADP (Future Strike Bomber, UAV, UCAV

  20. Magnetic manipulation of self-assembled colloidal asters.

    SciTech Connect (OSTI)

    Snezhko, A.; Aranson, I. S.

    2011-09-01

    Self-assembled materials must actively consume energy and remain out of equilibrium to support structural complexity and functional diversity. Here we show that a magnetic colloidal suspension confined at the interface between two immiscible liquids and energized by an alternating magnetic field dynamically self-assembles into localized asters and arrays of asters, which exhibit locomotion and shape change. By controlling a small external magnetic field applied parallel to the interface, we show that asters can capture, transport, and position target microparticles. The ability to manipulate colloidal structures is crucial for the further development of self-assembled microrobots

  1. Semiconductor nanocrystals covalently bound to solid inorganic surfaces using self-assembled monolayers

    DOE Patents [OSTI]

    Alivisatos, A. Paul; Colvin, Vicki L.

    1998-01-01

    Methods are described for attaching semiconductor nanocrystals to solid inorganic surfaces, using self-assembled bifunctional organic monolayers as bridge compounds. Two different techniques are presented. One relies on the formation of self-assembled monolayers on these surfaces. When exposed to solutions of nanocrystals, these bridge compounds bind the crystals and anchor them to the surface. The second technique attaches nanocrystals already coated with bridge compounds to the surfaces. Analyses indicate the presence of quantum confined clusters on the surfaces at the nanolayer level. These materials allow electron spectroscopies to be completed on condensed phase clusters, and represent a first step towards synthesis of an organized assembly of clusters. These new products are also disclosed.

  2. Semiconductor nanocrystals covalently bound to solid inorganic surfaces using self-assembled monolayers

    DOE Patents [OSTI]

    Alivisatos, A.P.; Colvin, V.L.

    1998-05-12

    Methods are described for attaching semiconductor nanocrystals to solid inorganic surfaces, using self-assembled bifunctional organic monolayers as bridge compounds. Two different techniques are presented. One relies on the formation of self-assembled monolayers on these surfaces. When exposed to solutions of nanocrystals, these bridge compounds bind the crystals and anchor them to the surface. The second technique attaches nanocrystals already coated with bridge compounds to the surfaces. Analyses indicate the presence of quantum confined clusters on the surfaces at the nanolayer level. These materials allow electron spectroscopies to be completed on condensed phase clusters, and represent a first step towards synthesis of an organized assembly of clusters. These new products are also disclosed. 10 figs.

  3. X-shaped Electro-Optic Chromophore with Remarkably Blue-Shifted Optical Absorption. Synthesis, Characterization, Linear/Nonlinear Optical Properties, Self-Assembly, and Thin Film Microstructural Characteristics

    SciTech Connect (OSTI)

    Kang,H.; Evmenenko, G.; Dutta, P.; Clays, K.; Song, K.; Marks, T.

    2006-01-01

    A novel type of 'X-shaped' two-dimensional electro-optic (EO) chromophore with extended conjugation has been synthesized and characterized. This chromophore is found to exhibit a remarkably blue-shifted optical maximum (357 nm in CH{sub 2}Cl{sub 2}) while maintaining a very large first hyperpolarizability ({beta}). Hyper-Rayleigh Scattering (HRS) measurements at 800 nm provide a {beta}{sub zzz} value of 1840 x 10{sup -30} esu. Self-assembled thin films of this chromophore were fabricated via a layer-by-layer chemisorptive siloxane-based approach. The chromophoric multilayers have been characterized by transmission optical spectroscopy, advancing contact angle measurements, synchrotron X-ray reflectivity, atomic force microscopy, and angle-dependent polarized second harmonic generation spectroscopy. The self-assembled chromophoric films exhibit a dramatically blue-shifted optical maximum (325 nm) while maintaining a large EO response ({chi}({sup 2}){sub 333} {approx} 232 pm/V at 1064 nm; r{sub 33} {approx} 45 pm/V at 1310 nm). This work demonstrates an attractive approach to developing EO materials offering improved nonlinearity-transparency trade-offs.

  4. Nano-engineering by optically directed self-assembly.

    SciTech Connect (OSTI)

    Furst, Eric; Dunn, Elissa; Park, Jin-Gyu; Brinker, C. Jeffrey; Sainis, Sunil; Merrill, Jason; Dufresne, Eric; Reichert, Matthew D.; Brotherton, Christopher M.; Bogart, Katherine Huderle Andersen; Molecke, Ryan A.; Koehler, Timothy P.; Bell, Nelson Simmons; Grillet, Anne Mary; Gorby, Allen D.; Singh, John; Lele, Pushkar; Mittal, Manish

    2009-09-01

    Lack of robust manufacturing capabilities have limited our ability to make tailored materials with useful optical and thermal properties. For example, traditional methods such as spontaneous self-assembly of spheres cannot generate the complex structures required to produce a full bandgap photonic crystals. The goal of this work was to develop and demonstrate novel methods of directed self-assembly of nanomaterials using optical and electric fields. To achieve this aim, our work employed laser tweezers, a technology that enables non-invasive optical manipulation of particles, from glass microspheres to gold nanoparticles. Laser tweezers were used to create ordered materials with either complex crystal structures or using aspherical building blocks.

  5. Composition and method for self-assembly and mineralization of peptide-amphiphiles

    DOE Patents [OSTI]

    Stupp, Samuel I.; Beniash, Elia; Hartgerink, Jeffrey D.

    2012-02-28

    The present invention is directed to a composition useful for making homogeneously mineralized self assembled peptide-amphiphile nanofibers and nanofiber gels. The composition is generally a solution comprised of a positively or negatively charged peptide-amphiphile and a like signed ion from the mineral. Mixing this solution with a second solution containing a dissolved counter-ion of the mineral and/or a second oppositely charged peptide amphiphile, results in the rapid self assembly of the peptide-amphiphiles into a nanofiber gel and templated mineralization of the ions. Templated mineralization of the initially dissolved mineral cations and anions in the mixture occurs with preferential orientation of the mineral crystals along the fiber surfaces within the nanofiber gel. One advantage of the present invention is that it results in homogenous growth of the mineral throughout the nanofiber gel. Another advantage of the present invention is that the nanofiber gel formation and mineralization reactions occur in a single mixing step and under substantially neutral or physiological pH conditions. These homogeneous nanostructured composite materials are useful for medical applications especially the regeneration of damaged bone in mammals. This invention is directed to the synthesis of peptide-amphiphiles with more than one amphiphilic moment and to supramolecular compositions comprised of such multi-dimensional peptide-amphiphiles. Supramolecular compositions can be formed by self assembly of multi-dimensional peptide-amphiphiles by mixing them with a solution comprising a monovalent cation.

  6. Composition and method for self-assembly and mineralization of peptide amphiphiles

    DOE Patents [OSTI]

    Stupp, Samuel I.; Beniash, Elia; Hartgerink, Jeffrey D.

    2009-06-30

    The present invention is directed to a composition useful for making homogeneously mineralized self assembled peptide-amphiphile nanofibers and nanofiber gels. The composition is generally a solution comprised of a positively or negatively charged peptide-amphiphile and a like signed ion from the mineral. Mixing this solution with a second solution containing a dissolved counter-ion of the mineral and/or a second oppositely charged peptide amphiphile, results in the rapid self assembly of the peptide-amphiphiles into a nanofiber gel and templated mineralization of the ions. Templated mineralization of the initially dissolved mineral cations and anions in the mixture occurs with preferential orientation of the mineral crystals along the fiber surfaces within the nanofiber gel. One advantage of the present invention is that it results in homogenous growth of the mineral throughout the nanofiber gel. Another advantage of the present invention is that the nanofiber gel formation and mineralization reactions occur in a single mixing step and under substantially neutral or physiological pH conditions. These homogeneous nanostructured composite materials are useful for medical applications especially the regeneration of damaged bone in mammals. This invention is directed to the synthesis of peptide-amphiphiles with more than one amphiphilic moment and to supramolecular compositions comprised of such multi-dimensional peptide-amphiphiles. Supramolecular compositions can be formed by self assembly of multi-dimensional peptide-amphiphiles by mixing them with a solution comprising a monovalent cation.

  7. Synthesis of self-assembled layered double hydroxides/carbon composites by in situ solvothermal method and their application in capacitors

    SciTech Connect (OSTI)

    Wei, Jinbo; Wang, Jun; Song, Yanchao; Li, Zhanshuang; Gao, Zan; Mann, Tom; Zhang, Milin

    2012-12-15

    Nickel-aluminum layered double hydroxides/carbon (Ni-Al LDHs/C) composites have been successfully fabricated via a facile in situ water-ethanol system. LDHs nanosheets could highly disperse on the surface of colloidal carbonaceous spheres through the interfacial electrostatic force. Ni-Al LDHs/C composite electrode prepared at 50% ethanol system exhibits the highest capacitance of 1064 F g{sup -1} at a current of 2.5 A g{sup -1}, leading to a significant improvement in relation to each individual counterpart (3.5 and 463 F g{sup -1} for carbon and Ni-Al LDHs at 2.5 A g{sup -1}, respectively). And a possible mechanism was proposed for the formation of the composites. Highlights: Black-Right-Pointing-Pointer Ni-Al LDHs/C composites have been self-assembled by an in situ solvothermal method. Black-Right-Pointing-Pointer A possible growth mechanism to explain the composite is proposed. Black-Right-Pointing-Pointer Ni-Al LDHs/C composites display better electrochemical performance.

  8. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Self-Assembly of Polymer Nano-Elements on Sapphire Print Wednesday, 25 March 2009 00:00 Self-assembly of polymers promises to ...

  9. Tuning the reactivity of Al/Fe{sub 2}O{sub 3} nanoenergetic materials via an approach combining soft template self-assembly with sol–gel process process

    SciTech Connect (OSTI)

    Zhang, Tianfu; Wang, Zhen; Li, Guoping; Luo, Yunjun

    2015-10-15

    A bottom-up approach combining soft template self-assembly with sol–gel process, was adopted to prepare the assembled Al/Fe{sub 2}O{sub 3} nanoenergetic materials, assembly-Al/Fe{sub 2}O{sub 3} sample. The other two unassembled Al/Fe{sub 2}O{sub 3}a nanoenergetic materials, sol–gel–Al/Fe{sub 2}O{sub 3} sample and mixing-Al/Fe{sub 2}O{sub 3} sample, were prepared by sol–gel method and physical mixing method respectively. The assembly process within the preparation of the assembly-Al/Fe{sub 2}O{sub 3} sample was analyzed through the changes in the average hydrodynamic diameters of the particles and the micelles in solution. SEM, EDS and TEM tests were performed to demonstrate a significant improvement regarding to dispersity and arrangements of the Al and Fe{sub 2}O{sub 3} particles in the assembled samples, compared to that of the unassembled Al/Fe{sub 2}O{sub 3} samples. DSC test was employed to characterize the reactivity of the samples. The heat release of the assembled Al/Fe{sub 2}O{sub 3} sample was 2088 J/g, about 400 and 990 J/g more than that of the sol–gel–Al/Fe{sub 2}O{sub 3} sample and mixing-Al/Fe{sub 2}O{sub 3} sample, respectively. - Graphical abstract: Modified aluminum (Al) nanoparticles with hydrophobic surface assembled into the Brij S10 micelle in Fe(III) sol, then the well dispersed system was transformed into Al/Fe{sub 2}O{sub 3} nanoenergetic materials with high reactivity. - Highlights: • An approach combining soft template self-assembly with sol–gel process was adopted. • The aggregation of Al nanoparticles in the final product was reduced significantly. • The reactivity of Al/Fe{sub 2}O{sub 3} nanoenergetic materials was improved to a large extent.

  10. First self-assembled superconductor structure created > EMC2 News > The

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

    Energy Materials Center at Cornell First self-assembled superconductor structure created January 29th, 2016 › By Tom Fleischman Lindsay France/University Photography Group leader Ulrich Wiesner, right, the Spencer T. Olin Professor of Engineering, and graduate student and co-lead author Peter Beaucage, second from right, hold models of the self-assembled gyroid superconductor the group created. Also pictured are Bruce van Dover, left, professor in the Department of Materials Science and

  11. Surfactant mediated polyelectrolyte self-assembly

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

    Goswami, Monojoy; Borreguero Calvo, Jose M.; Pincus, Phillip A.; Sumpter, Bobby G.

    2015-11-25

    Self-assembly and dynamics of polyelectrolyte (PE) surfactant complex (PES) is investigated using molecular dynamics simulations. The complexation is systematically studied for five different PE backbone charge densities. At a fixed surfactant concentration the PES complexation exhibits pearl-necklace to agglomerated double spherical structures with a PE chain decorating the surfactant micelles. The counterions do not condense on the complex, but are released in the medium with a random distribution. The relaxation dynamics for three different length scales, polymer chain, segmental and monomer, show distinct features of the charge and neutral species; the counterions are fastest followed by the PE chain andmore » surfactants. The surfactant heads and tails have the slowest relaxation due to their restricted movement inside the agglomerated structure. At the shortest length scale, all the charge and neutral species show similar relaxation dynamics confirming Rouse behavior at monomer length scales. Overall, the present study highlights the structure-property relationship for polymer-surfactant complexation. These results will help improve the understanding of PES complex and should aid in the design of better materials for future applications.« less

  12. Surfactant mediated polyelectrolyte self-assembly

    SciTech Connect (OSTI)

    Goswami, Monojoy; Borreguero Calvo, Jose M.; Pincus, Phillip A.; Sumpter, Bobby G.

    2015-11-25

    Self-assembly and dynamics of polyelectrolyte (PE) surfactant complex (PES) is investigated using molecular dynamics simulations. The complexation is systematically studied for five different PE backbone charge densities. At a fixed surfactant concentration the PES complexation exhibits pearl-necklace to agglomerated double spherical structures with a PE chain decorating the surfactant micelles. The counterions do not condense on the complex, but are released in the medium with a random distribution. The relaxation dynamics for three different length scales, polymer chain, segmental and monomer, show distinct features of the charge and neutral species; the counterions are fastest followed by the PE chain and surfactants. The surfactant heads and tails have the slowest relaxation due to their restricted movement inside the agglomerated structure. At the shortest length scale, all the charge and neutral species show similar relaxation dynamics confirming Rouse behavior at monomer length scales. Overall, the present study highlights the structure-property relationship for polymer-surfactant complexation. These results will help improve the understanding of PES complex and should aid in the design of better materials for future applications.

  13. Preface: Special Topic on Supramolecular Self-Assembly at Surfaces

    SciTech Connect (OSTI)

    Bartels, Ludwig; Ernst, Karl-Heinz; Gao, Hong-Jun; Thiel, Patricia A.

    2015-03-14

    Supramolecular self-assembly at surfaces is one of the most exciting and active fields in Surface Science today. Applications can take advantage of two key properties: (i) versatile pattern formation over a broad length scale and (ii) tunability of electronic structure and transport properties, as well as frontier orbital alignment. It provides a new frontier for Chemical Physics as it uniquely combines the versatility of Organic Synthesis and the Physics of Interfaces. The Journal of Chemical Physics is pleased to publish this Special Topic Issue, showcasing recent advances and new directions.

  14. Molecular pathways for defect annihilation in directed self-assembly.

    SciTech Connect (OSTI)

    Hur, Su-Mi; Thapar, Vikram; Ramirez-Hernandez, Abelardo; Khaira, Gurdaman S.; Segal-Peretz, Tamar; Rincon-Delgadillo, Paulina A.; Li, Weihua; Muller, Marcus; Nealey, Paul F.; de Pablo, Juan J.

    2015-11-17

    Over the last few years, the directed self-assembly of block copolymers by surface patterns has transitioned from academic curiosity to viable contender for commercial fabrication of next-generation nanocircuits by lithography. Recently, it has become apparent that kinetics, and not only thermodynamics, plays a key role for the ability of a polymeric material to self-assemble into a perfect, defect-free ordered state. Perfection, in this context, implies not more than one defect, with characteristic dimensions on the order of 5 nm, over a sample area as large as 100 cm2. In this work, we identify the key pathways and the corresponding free-energy barriers for eliminating defects, and we demonstrate that an extraordinarily large thermodynamic driving force is not necessarily sufficient for their removal. By adopting a concerted computational and experimental approach, we explain the molecular origins of these barriers, how they depend on material characteristics, and we propose strategies designed to over-come them. The validity of our conclusions for industrially-relevant patterning processes is established by relying on instruments and assembly lines that are only available at state-of-the-art fabrication facilities and, through this confluence of fundamental and applied research, we are able to discern the evolution of morphology at the smallest relevant length scales - a handful of nanometers -, and present a view of defect annihilation in directed self-assembly at an unprecedented level of detail.

  15. Self-Assembly of Polymer Nano-Elements on Sapphire

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

    Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers ... electron-beam lithographic techniques or nano-imprint lithography, but these methods are ...

  16. A New Route to Nano Self-Assembly

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

    A New Route to Nano Self-Assembly A New Route to Nano Self-Assembly Print Wednesday, 24 February 2010 00:00 If the promise of nanotechnology is to be fulfilled, nanoparticles will ...

  17. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Guided Self-Assembly of Gold Thin Films Print Wednesday, 21 November 2012 12:18 Nanoparticles-man-made atoms with unique optical, ...

  18. Electrostatically Self-assembled Amphiplexes

    SciTech Connect (OSTI)

    Helmut H. Strey

    2011-02-15

    This research will focus on characterizing the phase behavior of polyelectrolyte-surfactant microemulsions (PSM) that were recently discovered in our lab and indentifing possible uses of their long-range ordered nanostructures towards bioseparation, oil-recovery and drug delivery systems. In addition, we are proposing strategies for synthesizing solid and long-range ordered materials with unit cells on the nanometer scale using polymerization and/or cross-linking to solidify the soft template.

  19. Self-Assembled, Nanostructured Carbon for Energy Storage and Water Treatment

    SciTech Connect (OSTI)

    2009-03-01

    This factsheet describes a research project whose goal is to translate a unique approach for the synthesis of self-assembled nanostructured carbon into industrially viable technologies for two important, large-scale applications: electrochemical double-layer capacitors (also referred to as ultracapacitors) for electrical energy storage, and capacitive deionization (CDI) systems for water treatment and desalination.

  20. Self-assembling membranes and related methods thereof

    DOE Patents [OSTI]

    Capito, Ramille M; Azevedo, Helena S; Stupp, Samuel L

    2013-08-20

    The present invention relates to self-assembling membranes. In particular, the present invention provides self-assembling membranes configured for securing and/or delivering bioactive agents. In some embodiments, the self-assembling membranes are used in the treatment of diseases, and related methods (e.g., diagnostic methods, research methods, drug screening).

  1. Controlled Self-Assembly in Ternary Polymers

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

    Controlled Self-Assembly in Ternary Polymers - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management

  2. Self-assembled ultra small ZnO nanocrystals for dye-sensitized solar cell application

    SciTech Connect (OSTI)

    Patra, Astam K.; Dutta, Arghya; Bhaumik, Asim

    2014-07-01

    We demonstrate a facile chemical approach to produce self-assembled ultra-small mesoporous zinc oxide nanocrystals using sodium salicylate (SS) as a template under hydrothermal conditions. These ZnO nanomaterials have been successfully fabricated as a photoanode for the dye-sensitized solar cell (DSSC) in the presence of N719 dye and iodinetriiodide electrolyte. The structural features, crystallinity, purity, mesophase and morphology of the nanostructure ZnO are investigated by several characterization tools. N{sub 2} sorption analysis revealed high surface areas (203 m{sup 2} g{sup ?1}) and narrow pore size distributions (5.15.4 nm) for different samples. The mesoporous structure and strong photoluminescence facilitates the high dye loading at the mesoscopic void spaces and light harvesting in DSSC. By utilizing this ultra-small ZnO photoelectrode with film thickness of about 7 ?m in the DSSC with an open-circuit voltage (V{sub OC}) of 0.74 V, short-circuit current density (J{sub SC}) of 3.83 mA cm{sup ?2} and an overall power conversion efficiency of 1.12% has been achieved. - Graphical abstract: Ultra-small ZnO nanocrystals have been synthesized with sodium salicylate as a template and using it as a photoanode in a dye-sensitized solar cell 1.12% power conversion efficiency has been observed. - Highlights: Synthesis of self-assembled ultra-small mesoporous ZnO nanocrystals by using sodium salicylate as a template. Mesoporous ZnO materials have high BET surface areas and void space. ZnO nanoparticles serve as a photoanode for the dye-sensitized solar cell (DSSC). Using ZnO nanocrystals as photoelectrode power conversion efficiency of 1.12% has been achieved.

  3. Computational Design of Self-Assembling Protein Nanomaterials with Atomic Level Accuracy

    SciTech Connect (OSTI)

    King, Neil P.; Sheffler, William; Sawaya, Michael R.; Vollmar, Breanna S.; Sumida, John P.; André, Ingemar; Gonen, Tamir; Yeates, Todd O.; Baker, David

    2015-09-17

    We describe a general computational method for designing proteins that self-assemble to a desired symmetric architecture. Protein building blocks are docked together symmetrically to identify complementary packing arrangements, and low-energy protein-protein interfaces are then designed between the building blocks in order to drive self-assembly. We used trimeric protein building blocks to design a 24-subunit, 13-nm diameter complex with octahedral symmetry and a 12-subunit, 11-nm diameter complex with tetrahedral symmetry. The designed proteins assembled to the desired oligomeric states in solution, and the crystal structures of the complexes revealed that the resulting materials closely match the design models. The method can be used to design a wide variety of self-assembling protein nanomaterials.

  4. Emergence of reconfigurable wires and spinners via dynamic self-assembly

    SciTech Connect (OSTI)

    Kokot, Gasper; Piet, David; Whitesides, George M.; Aranson, Igor S.; Snezhko, Alexey

    2015-03-26

    Dissipative colloidal materials use energy to generate and maintain structural complexity. The energy injection rate, and properties of the environment are important control parameters that influence the outcome of dynamic self-assembly. Here we demonstrate that dispersions of magnetic microparticles confined at the air-liquid interface, and energized by a uniaxial in-plane alternating magnetic field, self-assemble into a variety of structures that range from pulsating clusters and single-particle-thick wires to dynamic arrays of spinners (self-assembled short chains) rotating in either direction. The spinners emerge via spontaneous breaking of the uniaxial symmetry of the energizing magnetic field. Demonstration of the formation and disaggregation of particle assemblies suggests strategies to form new meso-scale structures with the potential to perform functions such as mixing and sensing.

  5. Emergence of reconfigurable wires and spinners via dynamic self-assembly

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

    Kokot, Gasper; Piet, David; Whitesides, George M.; Aranson, Igor S.; Snezhko, Alexey

    2015-03-26

    Dissipative colloidal materials use energy to generate and maintain structural complexity. The energy injection rate, and properties of the environment are important control parameters that influence the outcome of dynamic self-assembly. Here we demonstrate that dispersions of magnetic microparticles confined at the air-liquid interface, and energized by a uniaxial in-plane alternating magnetic field, self-assemble into a variety of structures that range from pulsating clusters and single-particle-thick wires to dynamic arrays of spinners (self-assembled short chains) rotating in either direction. The spinners emerge via spontaneous breaking of the uniaxial symmetry of the energizing magnetic field. Demonstration of the formation and disaggregationmore » of particle assemblies suggests strategies to form new meso-scale structures with the potential to perform functions such as mixing and sensing.« less

  6. Directing Self-Assembly of Heterogeneous NanoSystems | MIT-Harvard Center

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

    for Excitonics Directing Self-Assembly of Heterogeneous NanoSystems December 5, 2013 at 3pm/36-428 Alfredo Alexander-Katz Department of Material Science and Engineering, Massachusetts Institute of Technology alexander-katz_004 Abstract: Directed self-assembly of block copolymers is a route to obtain tailored 2D patterns on the 10nm scale that have a high degree of order. These patterns are promising for applications in multiple areas, including sub 10nm lithography, light harvesting, and

  7. Nanoparticle Superlattices by Self-Assembly | The Ames Laboratory

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

    Nanoparticle Superlattices by Self-Assembly The project involves using state of the art computational tools: Python programming and Graphic Processing Units (GPUs) to develop...

  8. Self-assembled software and method of overriding software execution

    DOE Patents [OSTI]

    Bouchard, Ann M.; Osbourn, Gordon C.

    2013-01-08

    A computer-implemented software self-assembled system and method for providing an external override and monitoring capability to dynamically self-assembling software containing machines that self-assemble execution sequences and data structures. The method provides an external override machine that can be introduced into a system of self-assembling machines while the machines are executing such that the functionality of the executing software can be changed or paused without stopping the code execution and modifying the existing code. Additionally, a monitoring machine can be introduced without stopping code execution that can monitor specified code execution functions by designated machines and communicate the status to an output device.

  9. A New Route to Nano Self-Assembly

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

    critical to tailoring the macroscopic properties during nanoparticle assembly. Although DNA has been used to induce self-assembly of nanoparticles with a high degree of...

  10. Self Assembly of Boronic Acid-Functionalized Peptides. (Conference...

    Office of Scientific and Technical Information (OSTI)

    Title: Self Assembly of Boronic Acid-Functionalized Peptides. Abstract not provided. Authors: Jones, Brad Howard ; Martinez, Alina Marissa ; Wheeler, Jill S. ; McKenzie, Bonnie B. ...

  11. Charge Retention by Organometallic Dications on Self-Assembled...

    Office of Scientific and Technical Information (OSTI)

    Charge Retention by Organometallic Dications on Self-Assembled Monolayer Surfaces Citation Details In-Document Search Title: Charge Retention by Organometallic Dications on ...

  12. Guided Self-Assembly of Gold Thin Films

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

    Berkeley Lab and UC Berkeley scientists have made progress toward this goal, successfully directing the self--assembly of nanoparticles into device-ready thin films, which have...

  13. Computational Design of Self-Assembling Protein Nanomaterials...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Computational Design of Self-Assembling Protein Nanomaterials with Atomic Level Accuracy Citation Details In-Document Search Title: ...

  14. Fabrication of Transparent Capacitive Structure by Self-Assembled Thin Films

    SciTech Connect (OSTI)

    Zhang, Q.; Shing, Y. J.; Hua, Feng; Saraf, Laxmikant V.; Matson, Dean W.

    2008-06-01

    An approach to fabricating transparent electronic devices by using nanomaterial and nanofabrication is presented in this paper. A see-through capacitor is constructed from selfassembled silica nanoparticle layers that are stacked on the transparent substrate. The electrodes are made of indium tin oxide. Unlike the traditional processes used to fabricate such devices, the self-assembly approach enables one to synthesize the thin film layers at lower temperature and cost, and with a broader availability of nanomaterials. The vertical dimension of the selfassembled thin films can be precisely controlled, as well as the molecular order in the thin film layers. The shape of the capacitor is generated by planar micropatterning. The quartz crystal demonstrates the steady growth of the silica nanoparticle multilayer. In addition, because the nanomaterial synthesis and the device fabrication steps are separate, the device is not affected by the harsh conditions required for the material synthesis. A clear pattern is allowed over a large area on the substrate. The prepared capacitive structure has an optical transparency higher than 92% over the visible spectrum. The capacitive impedance is measured at different frequencies and fit the theoretical results. As one of the fundamental components, this type of capacitive structure can serve in the transparent circuits, interactive media and sensors, as well as being applicable to other transparent devices.

  15. Self-assembling multimeric nucleic acid constructs

    DOE Patents [OSTI]

    Cantor, Charles R.; Niemeyer, Christof M.; Smith, Cassandra L.; Sano, Takeshi; Hnatowich, Donald J.; Rusckowski, Mary

    1999-10-12

    The invention is directed to constructs and compositions containing multimeric forms of nucleic acid. Multimeric nucleic acids comprise single-stranded nucleic acids attached via biotin to streptavidin and bound with a functional group. These constructs can be utilized in vivo to treat or identify diseased tissue or cells. Repeated administrations of multimeric nucleic acid compositions produce a rapid and specific amplification of nucleic acid constructs and their attached functional groups. For treatment purposes, functional groups may be toxins, radioisotopes, genes or enzymes. Diagnostically, labeled multimeric constructs may be used to identify specific targets in vivo or in vitro. Multimeric nucleic acids may also be used in nanotechnology and to create self-assembling polymeric aggregates such as membranes of defined porosity, microcircuits and many other products.

  16. Self-assembling multimeric nucleic acid constructs

    DOE Patents [OSTI]

    Cantor, Charles R.; Niemeyer, Christof M.; Smith, Cassandra L.; Sano, Takeshi; Hnatowich, Donald J.; Rusckowski, Mary

    1996-01-01

    The invention is directed to constructs and compositions containing multimeric forms of nucleic acid. Multimeric nucleic acids comprise single-stranded nucleic acids attached via biotin to streptavidin and bound with a functional group. These constructs can be utilized in vivo to treat or identify diseased tissue or cells. Repeated administrations of multimeric nucleic acid compositions produce a rapid and specific amplification of nucleic acid constructs and their attached functional groups. For treatment purposes, functional groups may be toxins, radioisotopes, genes or enzymes. Diagnostically, labeled multimeric constructs may be used to identify specific targets in vivo or in vitro. Multimeric nucleic acids may also be used in nanotechnology and to create self-assembling polymeric aggregates such as membranes of defined porosity, microcircuits and many other products.

  17. Self-assembling multimeric nucleic acid constructs

    DOE Patents [OSTI]

    Cantor, C.R.; Niemeyer, C.M.; Smith, C.L.; Sano, Takeshi; Hnatowich, D.J.; Rusckowski, M.

    1996-10-01

    The invention is directed to constructs and compositions containing multimeric forms of nucleic acid. Multimeric nucleic acids comprise single-stranded nucleic acids attached via biotin to streptavidin and bound with a functional group. These constructs can be utilized in vivo to treat or identify diseased tissue or cells. Repeated administrations of multimeric nucleic acid compositions produce a rapid and specific amplification of nucleic acid constructs and their attached functional groups. For treatment purposes, functional groups may be toxins, radioisotopes, genes or enzymes. Diagnostically, labeled multimeric constructs may be used to identify specific targets in vivo or in vitro. Multimeric nucleic acids may also be used in nanotechnology and to create self-assembling polymeric aggregates such as membranes of defined porosity, microcircuits and many other products. 5 figs.

  18. Synthesis of refractory materials

    DOE Patents [OSTI]

    Holt, J.B.

    Refractory metal nitrides are synthesized during a combustion process utilizing a solid source of nitrogen. For this purpose, a metal azide is employed. The azide is combusted with a transition metal of the IIIB, IVB group, or a rare earth metal, and ignited to produce the refractory material.

  19. Electrostatically Tuned Self-Assembly of Branched Amphiphilic Peptides

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

    Ting, Christina L.; Frischknecht, Amalie L.; Stevens, Mark J.; Spoerke, Erik D.

    2014-06-19

    Electrostatics plays an important role in the self-assembly of amphiphilic peptides. To develop a molecular understanding of the role of the electrostatic interactions, we develop a coarse-grained model peptide and apply self-consistent field theory to investigate the peptide assembly into a variety of aggregate nanostructures. We find that the presence and distribution of charged groups on the hydrophilic branches of the peptide can modify the molecular configuration from extended to collapsed. This change in molecular configuration influences the packing into spherical micelles, cylindrical micelles (nanofibers), or planar bilayers. The effects of charge distribution therefore has important implications for the designmore » and utility of functional materials based on peptides.« less

  20. Combinatorial synthesis of novel materials

    DOE Patents [OSTI]

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2002-02-12

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  1. Combinatorial synthesis of novel materials

    DOE Patents [OSTI]

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    1999-01-01

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  2. Combinatorial synthesis of novel materials

    DOE Patents [OSTI]

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    1999-12-21

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  3. Combinatorial synthesis of novel materials

    DOE Patents [OSTI]

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2001-01-01

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  4. Synthesis of refractory materials

    DOE Patents [OSTI]

    Holt, Joseph B.

    1984-01-01

    Refractory metal nitrides are synthesized during a self-propagating combustion process utilizing a solid source of nitrogren. For this purpose, a metal azide is employed, preferably NaN.sub.3. The azide is combusted with Mg or Ca, and a metal oxide is selected from Groups III-A, IV-A, III-B, IV-B, or a rare earth metal oxide. The mixture of azide, Ca or Mg and metal oxide is heated to the mixture's ignition temperature. At that temperature the mixture is ignited and undergoes self-sustaining combustion until the starter materials are exhausted, producing the metal nitride.

  5. Synthesis of refractory materials

    DOE Patents [OSTI]

    Holt, J.B.

    1983-08-16

    Refractory metal nitrides are synthesized during a self-propagating combustion process utilizing a solid source of nitrogen. For this purpose, a metal azide is employed, preferably NaN/sub 3/. The azide is combusted with Mg or Ca, and a metal oxide is selected from Groups III-A, IV-A, III-B, IV-B, or a rare earth metal oxide. The mixture of azide, Ca or Mg and metal oxide is heated to the mixture's ignition temperature. At that temperature the mixture is ignited and undergoes self-sustaining combustion until the starter materials are exhausted, producing the metal nitride.

  6. Solvent mediated self-assembly of solids

    SciTech Connect (OSTI)

    De Yoreo, J.; Wilson, W.D.; Palmore, T.

    1997-12-12

    Solvent-mediated crystallization represents a robust approach to self-assembly of nanostructures and microstructures. In organic systems, the relative ease with which the structure of hydrogen- bonded molecules can be manipulated allows for generation of a wide variety of nanoscale crystal structures. In living organisms, control over the micron-to-millimeter form of inorganic crystals is achieved through introduction of bio-organic molecules. The purpose of this proposal is to understand the interplay between solution chemistry, molecular structure, surface chemistry, and the processes of nucleation and crystal growth in solvent-mediated systems, with the goal of developing the atomic and molecular basis of a solvent-mediated self-assembly technology. We will achieve this purpose by: (1) utilizing an atomic force microscopy (AFM) approach that provides in situ, real time imaging during growth from solutions, (2) by modifying kinetic Monte Carlo (KMC) models to include solution-surface kinetics, (3) by introducing quantum chemistry (QC) calculations of the potentials of the relevant chemical species and the near-surface structure of the solution, and (4) by utilizing molecular dynamics (MD) simulations to identify the minimum energy pathways to the solid state. Our work will focus on two systems chosen to address both the manometer and micron-to-millimeter length scales of assembly, the family of 2,5- diketopiperazines (X-DKPs) and the system of CaCO{sub 3} with amino acids. Using AFM, we will record the evolution of surface morphology, critical lengths, step speeds, and step-step interactions as a function of supersaturation and temperature. In the case of the X-DKPs, these measurements will be repeated as the molecular structure of the growth unit is varied. In the case of CaCO{sub 3}, they will be performed as a function of solution chemistry including pH, ionic strength, and amino acid content. In addition, we will measure nucleation rates and orientations of

  7. Self-Assembly of Functional Polymers | MIT-Harvard Center for Excitonics

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

    Assembly of Functional Polymers May 9, 2013 at 3pm/36-428 Bradley Olsen Department of Chemical Engineering, Massachusetts Institute of Technology olsen_001 Abstract: Block copolymer self-assembly represents an elegant, low-cost technique for the fabrication of complex new soft materials. Critical for many of the applications for such materials is incorporating polymers with a given optical, electronic, or biological functionality into the nanostructured material. In contrast to traditional

  8. Self-assembling holographic biosensors and biocomputers.

    SciTech Connect (OSTI)

    Light, Yooli Kim; Bachand, George David (Sandia National Laboratories, Albuquerque, NM); Schoeniger, Joseph S.; Trent, Amanda M. (Sandia National Laboratories, Albuquerque, NM)

    2006-05-01

    We present concepts for self-assembly of diffractive optics with potential uses in biosensors and biocomputers. The simplest such optics, diffraction gratings, can potentially be made from chemically-stabilized microtubules migrating on nanopatterned tracks of the motor protein kinesin. We discuss the fabrication challenges involved in patterning sub-micron-scale structures with proteins that must be maintained in aqueous buffers to preserve their activity. A novel strategy is presented that employs dry contact printing onto glass-supported amino-silane monolayers of heterobifunctional crosslinkers, followed by solid-state reactions of these cross-linkers, to graft patterns of reactive groups onto the surface. Successive solution-phase addition of cysteine-mutant proteins and amine-reactive polyethylene glycol allows assembly of features onto the printed patterns. We present data from initial experiments showing successful micro- and nanopatterning of lines of single-cysteine mutants of kinesin interleaved with lines of polyethylene, indicating that this strategy can be employed to arrays of features with resolutions suitable for gratings.

  9. In situ microscopy of the self-assembly of branched nanocrystals in solution

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

    Sutter, Eli; Tkachenko, Alexei V.; Sutter, Peter; Roman Krahne; Arciniegas, Milena; Manna, Liberato; de Graaf, Joost

    2016-04-04

    Here, solution-phase self-assembly of nanocrystals into mesoscale structures is a promising strategy for constructing functional materials from nanoscale components. Liquid environments are key to self-assembly since they allow suspended nanocrystals to diffuse and interact freely, but they also complicate experiments. Real-time observations with single-particle resolution could have transformative impact on our understanding of nanocrystal self-assembly. Here we use real-time in situ imaging by liquid-cell electron microscopy to elucidate the nucleation and growth mechanism and properties of linear chains of octapod-shaped nanocrystals in their native solution environment. Statistical mechanics modelling based on these observations and using the measured chain-length distribution clarifiesmore » the relative importance of dipolar and entropic forces in the assembly process and gives direct access to the interparticle interaction. Our results suggest that monomer-resolved in situ imaging combined with modelling can provide unprecedented quantitative insight into the microscopic processes and interactions that govern nanocrystal self-assembly in solution.« less

  10. Seeing Gold Nanoparticles Self-Assemble with in situ Liquid Transmissi...

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

    Seeing Gold Nanoparticles Self-Assemble with in situ Liquid Transmission Electron Microscopy December 15, 2014 Tweet EmailPrint Scientific Achievement The self-assembly of gold...

  11. "Plastic" Solar Cells: Self-Assembly of Bulk Heterojunction

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

    Nano-Materials by Spontaneous Phase Separation | MIT-Harvard Center for Excitonics "Plastic" Solar Cells: Self-Assembly of Bulk Heterojunction Nano-Materials by Spontaneous Phase Separation October 20, 2009 at 3pm/36-428 Alan Heeger Department of Chemistry, University of California, Santa Barbara heeger abstract: Solar cells - Power from the Sun - can provide and must provide - a significant contribution to our future energy needs. The challenge is clear; we must create the

  12. A New Route to Nano Self-Assembly

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

    A New Route to Nano Self-Assembly Print If the promise of nanotechnology is to be ... available nanoparticles over multiple length scales, ranging from the nano to the macro. ...

  13. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique ... films from highly ordered one--, two- and three-dimensional arrays of gold nanoparticles. ...

  14. Self Assembly of Boronic Acid-Functionalized Peptides

    Office of Scientific and Technical Information (OSTI)

    500 nm Self Assembly of Boronic Add-Functionalized Peptides Brad H. Jones, Alina M. Martinez, Jill S. Wheeler, Bonnie B. McKenzie, David R. Wheeler, and Erik D. Spoerke October ...

  15. A New Route to Nano Self-Assembly

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

    to Nano Self-Assembly Print If the promise of nanotechnology is to be fulfilled, nanoparticles will have to be able to make something of themselves. An important advance toward...

  16. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of...

  17. A New Route to Nano Self-Assembly

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

    A New Route to Nano Self-Assembly Print If the promise of nanotechnology is to be fulfilled, nanoparticles will have to be able to make something of themselves. An important...

  18. A New Route to Nano Self-Assembly

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

    A New Route to Nano Self-Assembly Print If the promise of nanotechnology is to be fulfilled, nanoparticles will have to be able to make something of themselves. An important advance toward this goal has been achieved by researchers who have found a simple and yet powerfully robust way to induce nanoparticles to assemble themselves into complex arrays. By adding specific types of small molecules to mixtures of nanoparticles and polymers, they were able to direct the self-assembly of the

  19. A New Route to Nano Self-Assembly

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

    A New Route to Nano Self-Assembly Print If the promise of nanotechnology is to be fulfilled, nanoparticles will have to be able to make something of themselves. An important advance toward this goal has been achieved by researchers who have found a simple and yet powerfully robust way to induce nanoparticles to assemble themselves into complex arrays. By adding specific types of small molecules to mixtures of nanoparticles and polymers, they were able to direct the self-assembly of the

  20. A New Route to Nano Self-Assembly

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

    A New Route to Nano Self-Assembly Print If the promise of nanotechnology is to be fulfilled, nanoparticles will have to be able to make something of themselves. An important advance toward this goal has been achieved by researchers who have found a simple and yet powerfully robust way to induce nanoparticles to assemble themselves into complex arrays. By adding specific types of small molecules to mixtures of nanoparticles and polymers, they were able to direct the self-assembly of the

  1. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Guided Self-Assembly of Gold Thin Films Print Wednesday, 21 November 2012 12:18 Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies.

  2. Nanostructured self-assembly materials from neat and aqueous solutions of C18 lipid pro-drug analogues of Capecitabine?a chemotherapy agent. Focus on nanoparticulate cubosomes? of the oleyl analogue

    SciTech Connect (OSTI)

    Gong, Xiaojuan; Moghaddam, Minoo J.; Sagnella, Sharon M.; Conn, Charlotte E.; Mulet, Xavier; Danon, Stephen J.; Waddington, Lynne J.; Drummond, Calum J.

    2014-09-24

    A series of prodrug analogues based on the established chemotherapy agent, 5-fluorouracil, have been prepared and characterized. C18 alkyl and alkenyl chains with increasing degree of unsaturation were attached to the N{sup 4} position of the 5-fluorocytosine (5-FC) base via a carbamate bond. Physicochemical characterization of the prodrug analogues was carried out using a combination of differential scanning calorimetry, cross-polarized optical microscopy, X-ray diffraction and small-angle X-ray scattering. The presence of a monounsaturated oleyl chain was found to promote lyotropic liquid crystalline phase formation in excess water with a fluid lamellar phase observed at room temperature and one or more bicontinuous cubic phases at 37 C. The bulk phase was successfully dispersed into liposomes or cubosomes at room and physiological temperature respectively. In vitro toxicity of the nanoparticulate 5-FCOle dispersions was evaluated against several normal and cancer cell types over a 48 h period and exhibited an IC{sub 50} of 100 {micro}M against all cell types. The in vivo efficacy of 5-FCOle cubosomes was assessed against the highly aggressive mouse 4T1 breast cancer model and compared to Capecitabine (a water-soluble commercially available 5-FU prodrug) delivered at the same dosages. After 21 days of treatment, the 0.5 mmol 5-FCOle treatment group exhibited a significantly smaller average tumour volume than all other treatment groups including Capecitabine at similar dosage. These results exemplify the potential of self-assembled amphiphile prodrugs for delivery of bioactives in vivo.

  3. "Brick-and-Mortar" Self-Assembly Approach to Mesoporous Carbon

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

    Nanocomposites - Energy Innovation Portal Vehicles and Fuels Vehicles and Fuels Energy Storage Energy Storage Find More Like This Return to Search "Brick-and-Mortar" Self-Assembly Approach to Mesoporous Carbon Nanocomposites Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryMesoporous carbon materials lack sufficient ordering at the atomic scale to exhibit good conductivity properties and thermal stability. To date, mesoporous carbons

  4. Self-Assembled Monolayer And Method Of Making

    DOE Patents [OSTI]

    Fryxell, Glen E.; Zemanian, Thomas S.; Liu, Jun; Shin, Yongsoon

    2004-06-22

    According to the present invention, the previously known functional material having a self-assembled monolayer on a substrate has a plurality of assembly molecules each with an assembly atom with a plurality of bonding sites (four sites when silicon is the assembly molecule) wherein a bonding fraction (or fraction) of fully bonded assembly atoms (the plurality of bonding sites bonded to an oxygen atom) has a maximum when made by liquid solution deposition, for example a maximum of 40% when silicon is the assembly molecule, and maximum surface density of assembly molecules was 5 silanes per square nanometer. Note that bonding fraction and surface population are independent parameters. The method of the present invention is an improvement to the known method for making a siloxane layer on a substrate, wherein instead of a liquid phase solution chemistry, the improvement is a supercritical phase chemistry. The present invention has the advantages of greater fraction of oxygen bonds, greater surface density of assembly molecules and reduced time for reaction of about 5 minutes to about 24 hours.

  5. Self-assembled monolayer and method of making

    DOE Patents [OSTI]

    Fryxell, Glen E [Kennewick, WA; Zemanian, Thomas S [Richland, WA; Liu, Jun [West Richland, WA; Shin, Yongsoon [Richland, WA

    2003-03-11

    According to the present invention, the previously known functional material having a self-assembled monolayer on a substrate has a plurality of assembly molecules each with an assembly atom with a plurality of bonding sites (four sites when silicon is the assembly molecule) wherein a bonding fraction (or fraction) of fully bonded assembly atoms (the plurality of bonding sites bonded to an oxygen atom) has a maximum when made by liquid solution deposition, for example a maximum of 40% when silicon is the assembly molecule, and maximum surface density of assembly molecules was 5 silanes per square nanometer. Note that bonding fraction and surface population are independent parameters. The method of the present invention is an improvement to the known method for making a siloxane layer on a substrate, wherein instead of a liquid phase solution chemistry, the improvement is a supercritical phase chemistry. The present invention has the advantages of greater fraction of oxygen bonds, greater surface density of assembly molecules and reduced time for reaction of about 5 minutes to about 24 hours.

  6. Self-Assembled Monolayer And Method Of Making

    DOE Patents [OSTI]

    Fryxell, Glen E.; Zemanian, Thomas S.; Liu, Jun; Shin, Yongsoon

    2005-01-25

    According to the present invention, the previously known functional material having a self-assembled monolayer on a substrate has a plurality of assembly molecules each with an assembly atom with a plurality of bonding sites (four sites when silicon is the assembly molecule) wherein a bonding fraction (or fraction) of fully bonded assembly atoms (the plurality of bonding sites bonded to an oxygen atom) has a maximum when made by liquid solution deposition, for example a maximum of 40% when silicon is the assembly molecule, and maximum surface density of assembly molecules was 5 silanes per square nanometer. Note that bonding fraction and surface population are independent parameters. The method of the present invention is an improvement to the known method for making a siloxane layer on a substrate, wherein instead of a liquid phase solution chemistry, the improvement is a supercritical phase chemistry. The present invention has the advantages of greater fraction of oxygen bonds, greater surface density of assembly molecules and reduced time for reaction of about 5 minutes to about 24 hours.

  7. Self-assembled monolayer and method of making

    DOE Patents [OSTI]

    Fryxell, Glen E.; Zemanian, Thomas S.; Liu, Jun; Shin, Yongsoon

    2004-05-11

    According to the present invention, the previously known functional material having a self-assembled monolayer on a substrate has a plurality of assembly molecules each with an assembly atom with a plurality of bonding sites (four sites when silicon is the assembly molecule) wherein a bonding fraction (or fraction) of fully bonded assembly atoms (the plurality of bonding sites bonded to an oxygen atom) has a maximum when made by liquid solution deposition, for example a maximum of 40% when silicon is the assembly molecule, and maximum surface density of assembly molecules was 5 silanes per square nanometer. Note that bonding fraction and surface population are independent parameters. The method of the present invention is an improvement to the known method for making a siloxane layer on a substrate, wherein instead of a liquid phase solution chemistry, the improvement is a supercritical phase chemistry. The present invention has the advantages of greater fraction of oxygen bonds, greater surface density of assembly molecules and reduced time for reaction of about 5 minutes to about 24 hours.

  8. Low-power light guiding and localization in optoplasmonic chains obtained by directed self-assembly

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

    Ahn, Wonmi; Zhao, Xin; Hong, Yan; Reinhard, Bjorn M.

    2016-03-02

    Here, optoplasmonic structures contain plasmonic components embedded in a defined photonic environment to create synergistic interactions between photonic and plasmonic components. Here, we show that chains of optical microspheres containing gold nanoparticles in their evanescent field combine the light guiding properties of a microsphere chain with the light localizing properties of a plasmonic nanoantenna. We implement these materials through template guided self-assembly and investigate their fundamental electromagnetic working principles through combination of electromagnetic simulations and experimental characterization. We demonstrate that optoplasmonic chains implemented by directed self-assembly achieve a significant reduction in guiding losses when compared with conventional plasmonic waveguides and,more » at the same time, retain the light localizing properties of plasmonic antennas at pre-defined locations. The results reinforce the potential of optoplasmonic structures for realizing low-loss optical interconnects with high bandwidth.« less

  9. Electrostatic self-assembly of graphene oxide wrapped sulfur particles for lithium–sulfur batteries

    SciTech Connect (OSTI)

    Wu, Haiwei; Huang, Ying Zong, Meng; Ding, Xiao; Ding, Juan; Sun, Xu

    2015-04-15

    Highlights: • Researched graphene oxide wrapped sulfur particles for lithium–sulfur batteries. • New approach for core–shell GO/S composites by electrostatic self-assembly method. • Both core–shell structure and the GO support help to retard the diffusion of polysulfides during the electrochemical cycling process of GO/S cathode. - Abstract: A novel graphene oxide (GO)/sulfur (S) composite is developed by electrostatic self-assembly method. Remarkably, the core–shell structure of the composite and the GO support helps to retard the diffusion of polysulfides during the electrochemical cycling process. The GO/sulfur cathode presents enhanced cycling ability. Specific discharge capacities up to 494.7 mAh g{sup −1} over 200 cycles at 0.1 C is achieved with enhanced columbic efficiency around 95%, representing a good cathode material for lithium–sulfur batteries.

  10. Photo-Definable Self Assembled Maerials

    DOE Patents [OSTI]

    DOSHI, DHAVAL; [et al

    2004-10-26

    The present invention provides a mesoporous material comprising at least one region of mesoporous material patterned at a lithographic scale. The present invention also provides a a method for forming a patterned mesoporous material comprising: coating a sol on a substrate to form a film, the sol comprising: a templating molecule, a photoactivator generator, a material capable of being sol-gel processed, water, and a solvent; and exposing the film to light to form a patterned mesoporous material.

  11. A New Route to Nano Self-Assembly

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

    A New Route to Nano Self-Assembly A New Route to Nano Self-Assembly Print Wednesday, 24 February 2010 00:00 If the promise of nanotechnology is to be fulfilled, nanoparticles will have to be able to make something of themselves. An important advance toward this goal has been achieved by researchers who have found a simple and yet powerfully robust way to induce nanoparticles to assemble themselves into complex arrays. By adding specific types of small molecules to mixtures of nanoparticles and

  12. Backfilled, self-assembled monolayers and methods of making same

    DOE Patents [OSTI]

    Fryxell, Glen E.; Zemanian, Thomas S.; Addleman, R. Shane; Aardahl, Christopher L.; Zheng, Feng; Busche, Brad; Egorov, Oleg B.

    2009-06-30

    Backfilled, self-assembled monolayers and methods of making the same are disclosed. The self-assembled monolayer comprises at least one functional organosilane species and a substantially random dispersion of at least one backfilling organosilane species among the functional organosilane species, wherein the functional and backfilling organosilane species have been sequentially deposited on a substrate. The method comprises depositing sequentially a first organosilane species followed by a backfilling organosilane species, and employing a relaxation agent before or during deposition of the backfilling organosilane species, wherein the first and backfilling organosilane species are substantially randomly dispersed on a substrate.

  13. Structural simulations of nanomaterials self-assembled from ionic macrocycles.

    SciTech Connect (OSTI)

    van Swol, Frank B.; Medforth, Craig John

    2010-10-01

    Recent research at Sandia has discovered a new class of organic binary ionic solids with tunable optical, electronic, and photochemical properties. These nanomaterials, consisting of a novel class of organic binary ionic solids, are currently being developed at Sandia for applications in batteries, supercapacitors, and solar energy technologies. They are composed of self-assembled oligomeric arrays of very large anions and large cations, but their crucial internal arrangement is thus far unknown. This report describes (a) the development of a relevant model of nonconvex particles decorated with ions interacting through short-ranged Yukawa potentials, and (b) the results of initial Monte Carlo simulations of the self-assembly binary ionic solids.

  14. "Self-assembly of uniform polyhedral silver nanocrystals into densest packings and exotic superlattices"

    SciTech Connect (OSTI)

    Henzie, Joel; Grunwald, Michael; Widmer-Cooper, Asaph; Geissler, Phillip L.; Yang, Peidong

    2011-03-01

    Understanding how polyhedra pack into extended arrangements is integral to the design and discovery of crystalline materials at all length scales. Much progress has been made in enumerating and characterizing the packing of polyhedral shapes, and the self-assembly of polyhedral nanocrystals into ordered superstructures. However, directing the self-assembly of polyhedral nanocrystals into densest packings requires precise control of particle shape, polydispersity,interactions and driving forces. Here we show with experiment and computer simulation that a range of nanoscale Ag polyhedra can self-assemble into their conjectured densest packings. When passivated with adsorbing polymer, the polyhedra behave as quasi-hard particles and assemble into millimetre-sized three-dimensional supercrystals by sedimentation.We also show, by inducing depletion attraction through excess polymer in solution, that octahedra form an exotic superstructure with complex helical motifs rather than the densest Minkowski lattice. Such large-scale Ag supercrystals may facilitate the design of scalable three-dimensional plasmonic metamaterials for sensing, nanophotonics, and photocatalysis.

  15. Synthesis of bulk superhard semiconducting B-C material (Journal...

    Office of Scientific and Technical Information (OSTI)

    Synthesis of bulk superhard semiconducting B-C material Citation Details In-Document Search Title: Synthesis of bulk superhard semiconducting B-C material A bulk composite ...

  16. Evidence for the Bulk Nature of Self-Assembled Monolayer Surface...

    Office of Scientific and Technical Information (OSTI)

    Evidence for the Bulk Nature of Self-Assembled Monolayer Surface of Fluorinated Alkyl ... Citation Details In-Document Search Title: Evidence for the Bulk Nature of Self-Assembled ...

  17. Robust, self-assembled, biocompatible films

    DOE Patents [OSTI]

    Swanson, Basil I; Anderson, Aaron S.; Dattelbaum, Andrew M.; Schmidt, Jurgen G.

    2014-06-24

    The present invention provides a composite material including a substrate having an oxide surface, and, a continuous monolayer on the oxide surface, the monolayer including a silicon atom from a trifunctional alkyl/alkenyl/alkynyl silane group that attaches to the oxide surface, an alkyl/alkenyl/alkynyl portion of at least three carbon atoms, a polyalkylene glycol spacer group, and either a reactive site (e.g., a recognition ligand) or a site resistant to non-specific binding (e.g., a methoxy or the like) at the terminus of each modified SAM. The present invention further provides a sensor element, a sensor array and a method of sensing, each employing the composite material. Patterning is also provided together with backfilling to minimize non-specific binding.

  18. Self-assembly of peptide-amphiphile nanofibers under physiological conditions

    DOE Patents [OSTI]

    Stupp, Samuel I.; Hartgerink, Jeffrey D.; Beniash, Elia

    2010-06-29

    Peptide amphiphile compounds, compositions and methods for self-assembly or nanofibrous network formation under neutral or physiological conditions.

  19. Nanoparticle flow, ordering and self-assembly.

    SciTech Connect (OSTI)

    Schunk, Peter Randall; Brown, William Michael; Plimpton, Steven James; Lechman, Jeremy B.; Grest, Gary Stephen; Petersen, Matthew K.; in't Veld, Pieter J.

    2008-10-01

    Nanoparticles are now more than ever being used to tailor materials function and performance in differentiating technologies because of their profound effect on thermo-physical, mechanical and optical properties. The most feasible way to disperse particles in a bulk material or control their packing at a substrate is through fluidization in a carrier, followed by solidification through solvent evaporation/drying/curing/sintering. Unfortunately processing particles as concentrated, fluidized suspensions into useful products remains an art largely because the effect of particle shape and volume fraction on fluidic properties and suspension stability remains unexplored in a regime where particle-particle interaction mechanics is prevalent. To achieve a stronger scientific understanding of the factors that control nanoparticle dispersion and rheology we have developed a multiscale modeling approach to bridge scales between atomistic and molecular-level forces active in dense nanoparticle suspensions. At the largest length scale, two 'coarse-grained' numerical techniques have been developed and implemented to provide for high-fidelity numerical simulations of the rheological response and dispersion characteristics typical in a processing flow. The first is a coupled Navier-Stokes/discrete element method in which the background solvent is treated by finite element methods. The second is a particle based method known as stochastic rotational dynamics. These two methods provide a new capability representing a 'bridge' between the molecular scale and the engineering scale, allowing the study of fluid-nanoparticle systems over a wide range of length and timescales as well as particle concentrations. To validate these new methodologies, multi-million atoms simulations explicitly including the solvent have been carried out. These simulations have been vital in establishing the necessary 'subgrid' models for accurate prediction at a larger scale and refining the two coarse

  20. Drying/self-assembly of nanoparticle suspensions.

    SciTech Connect (OSTI)

    Cheng, Shengfeng; Plimpton, Steven James; Lechman, Jeremy B.; Grest, Gary Stephen

    2010-10-01

    The most feasible way to disperse particles in a bulk material or control their packing at a substrate is through fluidization in a carrier that can be processed with well-known techniques such as spin, drip and spray coating, fiber drawing, and casting. The next stage in the processing is often solidification involving drying by solvent evaporation. While there has been significant progress in the past few years in developing discrete element numerical methods to model dense nanoparticle dispersion/suspension rheology which properly treat the hydrodynamic interactions of the solvent, these methods cannot at present account for the volume reduction of the suspension due to solvent evaporation. As part of LDRD project FY-101285 we have developed and implemented methods in the current suite of discrete element methods to remove solvent particles and volume, and hence solvent mass from the liquid/vapor interface of a suspension to account for volume reduction (solvent drying) effects. To validate the methods large scale molecular dynamics simulations have been carried out to follow the evaporation process at the microscopic scale.

  1. Stable doping of carbon nanotubes via molecular self assembly

    SciTech Connect (OSTI)

    Lee, B.; Chen, Y.; Podzorov, V.; Cook, A.; Zakhidov, A.

    2014-10-14

    We report a novel method for stable doping of carbon nanotubes (CNT) based on methods of molecular self assembly. A conformal growth of a self-assembled monolayer of fluoroalkyl trichloro-silane (FTS) at CNT surfaces results in a strong increase of the sheet conductivity of CNT electrodes by 60–300%, depending on the CNT chirality and composition. The charge carrier mobility of undoped partially aligned CNT films was independently estimated in a field-effect transistor geometry (~100 cm²V⁻¹s⁻¹). The hole density induced by the FTS monolayer in CNT sheets is estimated to be ~1.8 ×10¹⁴cm⁻². We also show that FTS doping of CNT anodes greatly improves the performance of organic solar cells. This large and stable doping effect, easily achieved in large-area samples, makes this approach very attractive for applications of CNTs in transparent and flexible electronics.

  2. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal,

  3. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal,

  4. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal,

  5. Guided Self-Assembly of Gold Thin Films

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

    Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal,

  6. Sequential programmable self-assembly: Role of cooperative interactions

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

    Jonathan D. Halverson; Tkachenko, Alexei V.

    2016-03-04

    Here, we propose a general strategy of “sequential programmable self-assembly” that enables a bottom-up design of arbitrary multi-particle architectures on nano- and microscales. We show that a naive realization of this scheme, based on the pairwise additive interactions between particles, has fundamental limitations that lead to a relatively high error rate. This can be overcome by using cooperative interparticle binding. The cooperativity is a well known feature of many biochemical processes, responsible, e.g., for signaling and regulations in living systems. Here we propose to utilize a similar strategy for high precision self-assembly, and show that DNA-mediated interactions provide a convenientmore » platform for its implementation. In particular, we outline a specific design of a DNA-based complex which we call “DNA spider,” that acts as a smart interparticle linker and provides a built-in cooperativity of binding. We demonstrate versatility of the sequential self-assembly based on spider-functionalized particles by designing several mesostructures of increasing complexity and simulating their assembly process. This includes a number of finite and repeating structures, in particular, the so-called tetrahelix and its several derivatives. Due to its generality, this approach allows one to design and successfully self-assemble virtually any structure made of a “GEOMAG” magnetic construction toy, out of nanoparticles. According to our results, once the binding cooperativity is strong enough, the sequential self-assembly becomes essentially error-free.« less

  7. Self Assembly for Nanostructured Electronic Devices at the Center for

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

    Functional Nanomaterials | MIT-Harvard Center for Excitonics Self Assembly for Nanostructured Electronic Devices at the Center for Functional Nanomaterials November 3, 2009 at 3pm/36-428 Charles Black Center for Functional Nanomaterials, Brookhaven National Laboratory Black_Chuck_D0331112 abstract: The Center for Functional Nanomaterials (CFN) at Brookhaven National Laboratory is a science-based user facility devoted to nanotechnology research addressing challenges in energy security. Five

  8. Combinatorial synthesis of ceramic materials

    DOE Patents [OSTI]

    Lauf, Robert J.; Walls, Claudia A.; Boatner, Lynn A.

    2006-11-14

    A combinatorial library includes a gelcast substrate defining a plurality of cavities in at least one surface thereof; and a plurality of gelcast test materials in the cavities, at least two of the test materials differing from the substrate in at least one compositional characteristic, the two test materials differing from each other in at least one compositional characteristic.

  9. Combinatorial synthesis of ceramic materials

    DOE Patents [OSTI]

    Lauf, Robert J. [Oak Ridge, TN; Walls, Claudia A. [Oak Ridge, TN; Boatner, Lynn A. [Oak Ridge, TN

    2010-02-23

    A combinatorial library includes a gelcast substrate defining a plurality of cavities in at least one surface thereof; and a plurality of gelcast test materials in the cavities, at least two of the test materials differing from the substrate in at least one compositional characteristic, the two test materials differing from each other in at least one compositional characteristic.

  10. Structure of a designed protein cage that self-assembles into a highly porous cube

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

    Lai, Yen-Ting; Reading, Eamonn; Hura, Greg L.; Tsai, Kuang-Lei; Laganowsky, Arthur; Asturias, Francisco J.; Tainer, John A.; Robinson, Carol V.; Yeates, Todd O.

    2014-11-10

    Natural proteins can be versatile building blocks for multimeric, self-assembling structures. Yet, creating protein-based assemblies with specific geometries and chemical properties remains challenging. Highly porous materials represent particularly interesting targets for designed assembly. Here we utilize a strategy of fusing two natural protein oligomers using a continuous alpha-helical linker to design a novel protein that self assembles into a 750 kDa, 225 Å diameter, cube-shaped cage with large openings into a 130 Å diameter inner cavity. A crystal structure of the cage showed atomic level agreement with the designed model, while electron microscopy, native mass spectrometry, and small angle x-raymore » scattering revealed alternate assembly forms in solution. These studies show that accurate design of large porous assemblies with specific shapes is feasible, while further specificity improvements will likely require limiting flexibility to select against alternative forms. Finally, these results provide a foundation for the design of advanced materials with applications in bionanotechnology, nanomedicine and material sciences.« less

  11. Materials Synthesis and Integrated Devices

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

    Administration | (NNSA) Materials Science: the science of everything Friday, July 24, 2015 - 10:57am Y-12 Senior Metallurgist Steven Dekanich and NASA Materials Science Branch Chief Steve McDanels teamed up to lead a weeklong materials science camp that took at the University of Tennessee in Knoxville. The camp, which has been held since 2004, was jointly sponsored by Consolidated Nuclear Services (CNS), Oak Ridge National Laboratory, the University of Tennessee and the Knoxville chapter of

  12. Advanced Battery Materials Synthesis and Manufacturing R&D Program...

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

    Advanced Battery Materials Synthesis and Manufacturing R&D Program Argonne's Materials Engineering Research Facility (MERF) supports the laboratory's Advanced Battery Materials...

  13. Combinatorial synthesis of inorganic or composite materials

    DOE Patents [OSTI]

    Goldwasser, Isy; Ross, Debra A.; Schultz, Peter G.; Xiang, Xiao-Dong; Briceno, Gabriel; Sun, Xian-Dong; Wang, Kai-An

    2010-08-03

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials or, alternatively, allowing the components to interact to form at least two different materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, nonbiological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  14. Periodic nanostructures from self assembled wedge-type block-copolymers

    DOE Patents [OSTI]

    Xia, Yan; Sveinbjornsson, Benjamin R.; Grubbs, Robert H.; Weitekamp, Raymond; Miyake, Garret M.; Piunova, Victoria; Daeffler, Christopher Scot

    2015-06-02

    The invention provides a class of wedge-type block copolymers having a plurality of chemically different blocks, at least a portion of which incorporates a wedge group-containing block providing useful properties. For example, use of one or more wedge group-containing blocks in some block copolymers of the invention significantly inhibits chain entanglement and, thus, the present block copolymers materials provide a class of polymer materials capable of efficient molecular self-assembly to generate a range of structures, such as periodic nanostructures and microstructures. Materials of the present invention include copolymers having one or more wedge group-containing blocks, and optionally for some applications copolymers also incorporating one or more polymer side group-containing blocks. The present invention also provides useful methods of making and using wedge-type block copolymers.

  15. Phase Change Nanodots Patterning using a Self-Assembled Polymer Lithography and Crystallization Analysis

    SciTech Connect (OSTI)

    Zhang, Y.; Raoux, S; Krebs, D; Krupp, L; Topuria, T; Caldwell, M; Milliron, D; Kellock, A; Rice, P; et. al.

    2008-01-01

    Crystallization behavior of scalable phase change materials can be studied on nanoscale structures. In this paper, high density ordered phase change nanodot arrays were fabricated using the lift-off technique on a self-assembled diblock copolymer template, polystyrene-poly(methyl-methacrylate). The size of the nanodots was less than 15 nm in diameter with 40 nm spacing. This method is quite flexible regarding the patterned materials and can be used on different substrates. The crystallization behavior of small scale phase change nanodot arrays was studied using time-resolved x-ray diffraction, which showed the phase transition for different materials such as Ge15Sb85, Ge2Sb2Te5, and Ag and In doped Sb2Te. The transition temperatures of these nanodot samples were also compared with their corresponding blanket thin films, and it was found that the nanodots had higher crystallization temperatures and crystallized over a broader temperature range.

  16. Quantum & Energy Materials Capabilities | Argonne National Laboratory

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

    Quantum & Energy Materials Capabilities Synthesis Colloidal chemistry and self-assembly techniques Complex oxide film synthesis via molecular beam epitaxy (DCA R450 Custom) Glovebox system for organic photovoltaics device fabrication Physical vapor deposition (Lesker CMS 18 and PVD 250) Spin coating (Laurell WS-400) Characterization Variable-temperature (VT) scanning tunneling microscope with atomic force microscopy capabilities (Omicron VT-AFM/STM), operates in an ultrahigh vacuum (UHV)

  17. Cytoskeleton mimetic reinforcement of a self-assembled N,N'-dialkylimidazolium ionic liquid monomer by copolymerization.

    SciTech Connect (OSTI)

    Grubjesic, S.; Seifert, S.; Firestone, M. A.; Materials Science Division

    2009-08-11

    Preparation and photopolymerization of a decylmethylimidazolium ionic liquid (IL) that possesses an acrylate counteranion are described. This IL monomer self-assembles upon addition of water and can be copolymerized with poly(ethylene glycol) diacrylate (PEGDA) in the presence of a photoinitiator, forming a mechanically durable material that adopts a lamellar structure with in-plane hexagonally ordered pores, as evidenced by small-angle X-ray scattering (SAXS). Thermogravimetric analysis, the extent of polymerization, and solubility-swelling studies indicate the formation of a network copolymer of the IL monomer and the PEGDA. Additional evidence for the formation of a nanostructured copolymer is provided by evaluating the product formed by replacement of the IL monomer with the nonpolymerizable analogue, decylmethylimidazolium chloride. The results demonstrate the possibility of designing a self-assembled amiphiphilic bilayer architecture that is reinforced by polymerization and cross-linking.

  18. Functionalized Graphene Sheets as Molecular Templates for Controlled Nucleation and Self-Assembly of Metal Oxide-Graphene Nanocomposites

    SciTech Connect (OSTI)

    Li, Xiaolin; Qi, Wen N.; Mei, Donghai; Sushko, Maria L.; Aksay, Ilhan A.; Liu, Jun

    2012-09-25

    Graphene sheets have been extensively studied as a key functional component of graphene-based nanocomposites for electronics, energy, catalysis,and sensing applications. However, fundamental understanding of the interfacial binding and nucleation processes at graphene surfaces remains lacking, and the range of controlled structures that can be produced are limited. Here, by using a combination of theoretical and experimental approaches, we demonstrate that functionalized graphene sheets (FGS) can function as a new class of molecular templates to direct nucleation and self-assembly and produce novel, three-dimensional nanocomposite materials. Two key aspects are demonstrated: First, the functional groups on FGS surface determine the nucleation energy, and thus control the nucleation sites and nucleation density, as well as the preferred crystalline phases. Second, FGS can function as a template to direct the self-assembly of surfactant micelles and produce ordered, mesoporous arrays of crystalline metal oxides and composites.

  19. Oligo(p-phenylene vinylene) amphiphiles and methods for self-assembly

    DOE Patents [OSTI]

    Stupp, Samuel I.; Hulvat, James F.; Sofos, Marina; Tajima, Keisuke

    2008-05-13

    Amphiphilic oligo(p-phenylene vinylene) compounds and methods of use en route to self-assembled composites and device fabrication.

  20. Self-assembled Ni/TiO{sub 2} nanocomposite anodes synthesized...

    Office of Scientific and Technical Information (OSTI)

    Ni(core)TiOsub 2(shell) nanocomposite anodes were fabricated on three-dimensional, self-assembled nanotemplates of Tobacco mosaic virus using atomic layer deposition, exhibiting ...

  1. Self-assembly of mixtures of nanorods in binary, phase-separating...

    Office of Scientific and Technical Information (OSTI)

    Title: Self-assembly of mixtures of nanorods in binary, phase-separating blends Aligned nanorod inclusions have the potential to significantly improve both the photovoltaic and ...

  2. Energy level alignment of self-assembled linear chains of benzenediami...

    Office of Scientific and Technical Information (OSTI)

    Energy level alignment of self-assembled linear chains of benzenediamine on Au(111) from ... This content will become publicly available on March 24, 2017 Title: Energy level ...

  3. GeSi strained nanostructure self-assembly for nano- and opto...

    Office of Scientific and Technical Information (OSTI)

    to produce quantum nanostructures for nanologic and optoelectronics applications. Our current research direction aims to move beyond self-assembly of the basic quantum dot towards ...

  4. Controlling the photoconductivity: Graphene oxide and polyaniline self assembled intercalation

    SciTech Connect (OSTI)

    Vempati, Sesha; Ozcan, Sefika; Uyar, Tamer

    2015-02-02

    We report on controlling the optoelectronic properties of self-assembled intercalating compound of graphene oxide (GO) and HCl doped polyaniline (PANI). Optical emission and X-ray diffraction studies revealed a secondary doping phenomenon of PANI with OH and COOH groups of GO, which essentially arbitrate the intercalation. A control on the polarity and the magnitude of the photoresponse (PR) is harnessed by manipulating the weight ratios of PANI to GO (viz., 1:1.5 and 1:2.2 are abbreviated as PG1.5 and PG2.2, respectively), where PR?=?100(R{sub Dark} R{sub UV-Vis})/R{sub Dark} and R corresponds to the resistance of the device in dark or UV-Vis illumination. To be precise, the PR from GO, PANI, PG1.5, and PG2.2 are +34%, ?111%, ?51%, and +58%, respectively.

  5. Adsorption of Amelogenin onto Self-Assembled and Fluoroapatite Surfaces

    SciTech Connect (OSTI)

    Tarasevich, Barbara J.; Lea, Alan S.; Bernt, William; Engelhard, Mark H.; Shaw, Wendy J.

    2009-02-19

    Abstract. The interactions of proteins at surfaces are of great importance to biomineralizaton processes and to the development and function of biomaterials. Amelogenin is a unique biomineralization protein because it self-assembles to form supramolecular structures called “nanospheres,” spherical aggregates of monomers that are 20-60 nm in diameter. Although the nanosphere quaternary structure has been observed in solution, the quaternary structure of amelogenin adsorbed onto surfaces is also of great interest because the surface structure is critical to its function. We report studies of the adsorption of the amelogenin onto self-assembled monolayers (SAMs) with COOH and CH3 end group functionality and single crystal fluoroapatite (FAP). Dynamic light scattering (DLS) experiments showed that the solutions contained nanospheres and aggregates of nanospheres. Protein adsorption onto the various substrates was evidenced by null ellipsometry, x-ray photoelectron spectroscopy (XPS), and external reflectance Fourier transform infrared spectroscopy (ERFTIR). Although only nanospheres were observed in solution, ellipsometry and atomic force microscopy (AFM) indicated that the protein adsorbates were much smaller structures than the original nanospheres, from monomers to small oligomers in size. Monomer adsorption was promoted onto the CH3 surfaces and small oligomer adsorption was promoted onto the COOH and FAP substrates. In some cases, remnants of the original nanospheres adsorbed as multilayers on top of the underlying subnanosphere layers. This work suggests that amelogenin can adsorb by the “shedding” or disassembling of substructures from the nanospheres onto substrates and indicates that amelogenin may have a range of possible quaternary structures depending on whether it is in solution or interacting with surfaces.

  6. Self-Assembly, Molecular Ordering, and Charge Mobility in Solution-Processed Ultrathin Oligothiophene Films

    SciTech Connect (OSTI)

    Murphy,A.; Chang, P.; VanDyke, P.; Liu, J.; Frechet, J.; Subramanian, V.; Delongchamp, D.; Sambasivan, S.; Fischer, D.; Lin, E.

    2005-01-01

    Symmetrical {alpha}, {omega}-substituted quarter-(T4), penta-(T5), sexi-(T6), and heptathiophene (T7) oligomers containing thermally removable aliphatic ester solubilizing groups were synthesized, and their UV-vis and thermal characteristics were compared. Spun-cast thin films of each oligomer were examined with atomic force microscopy and near-edge X-ray absorption fine structure spectroscopy to evaluate the ability of the material to self-assemble from a solution-based process while maintaining complete surface coverage. Films of the T5-T7 oligomers self-assemble into crystalline terraces after thermal annealing with higher temperatures required to affect this transformation as the size of the oligomers increases. A symmetrical {alpha}, {omega}-substituted sexithiophene (T6-acid) that reveals carboxylic acids after thermolysis was also prepared to evaluate the effect of the presence of hydrogen-bonding moieties. The charge transport properties for these materials evaluated in top-contact thin film transistor devices were found to correlate with the observed morphology of the films. Therefore, the T4 and the T6-acid performed poorly because of incomplete surface coverage after thermolysis, while T5-T7 exhibited much higher performance as a result of molecular ordering. Increases in charge mobility correlated to increasing conjugation length with measured mobilities ranging from 0.02 to 0.06 cm2/(V{center_dot}s). The highest mobilities were measured when films of each oligomer had an average thickness between one and two monolayers, indicating that the molecules become exceptionally well-ordered during the thermolysis process. This unprecedented ordering of the solution-cast molecules results in efficient charge mobility rarely seen in such ultrathin films.

  7. Anandamide and analogous endocannabinoids: a lipid self-assembly study

    SciTech Connect (OSTI)

    Sagnella, Sharon M.; Conn, Charlotte E.; Krodkiewska, Irena; Mulet, Xavier; Drummond, Calum J.

    2014-09-24

    Anandamide, the endogenous agonist of the cannabinoid receptors, has been widely studied for its interesting biological and medicinal properties and is recognized as a highly significant lipid signaling molecule within the nervous system. Few studies have, however, examined the effect of the physical conformation of anandamide on its function. The study presented herein has focused on characterizing the self-assembly behaviour of anandamide and four other endocannabinoid analogues of anandamide, viz., 2-arachidonyl glycerol, arachidonyl dopamine, 2-arachidonyl glycerol ether (noladin ether), and o-arachidonyl ethanolamide (virodhamine). Molecular modeling of the five endocannabinoid lipids indicates that the highly unsaturated arachidonyl chain has a preference for a U or J shaped conformation. Thermal phase studies of the neat amphiphiles showed that a glass transition was observed for all of the endocannabinoids at {approx} -110 C with the exception of anandamide, with a second glass transition occurring for 2-arachidonyl glycerol, 2-arachidonyl glycerol ether, and virodhamine (-86 C, -95 C, -46 C respectively). Both anandamide and arachidonyl dopamine displayed a crystal-isotropic melting point (-4.8 and -20.4 C respectively), while a liquid crystal-isotropic melting transition was seen for 2-arachidonyl glycerol (-40.7 C) and 2-arachidonyl glycerol ether (-71.2 C). No additional transitions were observed for virodhamine. Small angle X-ray scattering and cross polarized optical microscopy studies as a function of temperature indicated that in the presence of excess water, both 2-arachidonyl glycerol and anandamide form co-existing Q{sub II}{sup G} (gyroid) and Q{sub II}{sup D} (diamond) bicontinuous cubic phases from 0 C to 20 C, which are kinetically stable over a period of weeks but may not represent true thermodynamic equilibrium. Similarly, 2-arachidonyl glycerol ether acquired an inverse hexagonal (HII) phase in excess water from 0 C to 40 C, while

  8. Toward a Materials Genome Approach for Ionic Liquids: Synthesis...

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

    Toward a Materials Genome Approach for Ionic Liquids: Synthesis Guided by Ab Initio Property Maps Previous Next List Fangyong Yan, Michael Lartey, Kuldeep Jariwala, Sage Bowser,...

  9. Stoichiometric control of DNA-grafted colloid self-assembly

    SciTech Connect (OSTI)

    Vo, Thi; Venkatasubramanian, Venkat; Kumar, Sanat; Srinivasan, Babji; Pal, Suchetan; Zhang, Yugang; Gang, Oleg

    2015-04-06

    In this study, there has been considerable interest in understanding the self-assembly of DNA-grafted nanoparticles into different crystal structures, e.g., CsCl, AlB?, and Cr?Si. Although there are important exceptions, a generally accepted view is that the right stoichiometry of the two building block colloids needs to be mixed to form the desired crystal structure. To incisively probe this issue, we combine experiments and theory on a series of DNA-grafted nanoparticles at varying stoichiometries, including noninteger values. We show that stoichiometry can couple with the geometries of the building blocks to tune the resulting equilibrium crystal morphology. As a concrete example, a stoichiometric ratio of 3:1 typically results in the Cr?Si structure. However, AlB? can form when appropriate building blocks are used so that the AlB? standard-state free energy is low enough to overcome the entropic preference for Cr?Si. These situations can also lead to an undesirable phase coexistence between crystal polymorphs. Thus, whereas stoichiometry can be a powerful handle for direct control of lattice formation, care must be taken in its design and selection to avoid polymorph coexistence.

  10. Stoichiometric control of DNA-grafted colloid self-assembly

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

    Vo, Thi; Venkatasubramanian, Venkat; Kumar, Sanat; Srinivasan, Babji; Pal, Suchetan; Zhang, Yugang; Gang, Oleg

    2015-04-06

    In this study, there has been considerable interest in understanding the self-assembly of DNA-grafted nanoparticles into different crystal structures, e.g., CsCl, AlB₂, and Cr₃Si. Although there are important exceptions, a generally accepted view is that the right stoichiometry of the two building block colloids needs to be mixed to form the desired crystal structure. To incisively probe this issue, we combine experiments and theory on a series of DNA-grafted nanoparticles at varying stoichiometries, including noninteger values. We show that stoichiometry can couple with the geometries of the building blocks to tune the resulting equilibrium crystal morphology. As a concrete example,more » a stoichiometric ratio of 3:1 typically results in the Cr₃Si structure. However, AlB₂ can form when appropriate building blocks are used so that the AlB₂ standard-state free energy is low enough to overcome the entropic preference for Cr₃Si. These situations can also lead to an undesirable phase coexistence between crystal polymorphs. Thus, whereas stoichiometry can be a powerful handle for direct control of lattice formation, care must be taken in its design and selection to avoid polymorph coexistence.« less

  11. Switchable friction enabled by nanoscale self-assembly on graphene

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

    Gallagher, Patrick; Lee, Menyoung; Amet, Francois; Maksymovych, Petro; Wang, Jun; Wang, Shuopei; Lu, Xiaobo; Zhang, Guangyu; Watanabe, Kenji; Taniguchi, Takashi; et al

    2016-02-23

    Graphene monolayers are known to display domains of anisotropic friction with twofold symmetry and anisotropy exceeding 200%. This anisotropy has been thought to originate from periodic nanoscale ripples in the graphene sheet, which enhance puckering around a sliding asperity to a degree determined by the sliding direction. Here we demonstrate that these frictional domains derive not from structural features in the graphene but from self-assembly of environmental adsorbates into a highly regular superlattice of stripes with period 4–6 nm. The stripes and resulting frictional domains appear on monolayer and multilayer graphene on a variety of substrates, as well as onmore » exfoliated flakes of hexagonal boron nitride. We show that the stripe-superlattices can be reproducibly and reversibly manipulated with submicrometre precision using a scanning probe microscope, allowing us to create arbitrary arrangements of frictional domains within a single flake. In conclusion, our results suggest a revised understanding of the anisotropic friction observed on graphene and bulk graphite in terms of adsorbates.« less

  12. Molecular self-assembly strategy for generating catalytic hybrid polypeptides

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

    Maeda, Yoshiaki; Fang, Justin; Ikezoe, Yasuhiro; Pike, Douglas H.; Nanda, Vikas; Matsui, Hiroshi

    2016-04-26

    Recently, catalytic peptides were introduced that mimicked protease activities and showed promising selectivity of products even in organic solvents where protease cannot perform well. However, their catalytic efficiency was extremely low compared to natural enzyme counterparts presumably due to the lack of stable tertiary fold. We hypothesized that assembling these peptides along with simple hydrophobic pockets, mimicking enzyme active sites, could enhance the catalytic activity. Here we fused the sequence of catalytic peptide CP4, capable of protease and esterase-like activities, into a short amyloidogenic peptide fragment of Aβ. When the fused CP4-Aβ construct assembled into antiparallel β- sheets and amyloidmore » fibrils, a 4.0-fold increase in the hydrolysis rate of p-nitrophenyl acetate (p-NPA) compared to neat CP4 peptide was observed. Furthermore, the enhanced catalytic activity of CP4-Aβ assembly could be explained both by pre-organization of a catalytically competent Ser-His-acid triad and hydrophobic stabilization of a bound substrate between the triad and p-NPA, indicating that a design strategy for self-assembled peptides is important to accomplish the desired functionality.« less

  13. CMI Unique Facility: Bulk Combinatoric Materials Synthesis Facility |

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

    Critical Materials Institute Bulk Combinatoric Materials Synthesis Facility The Bulk Combinatoric Materials Synthesis Facility is one of more than a dozen unique facilities developed by the Critical Materials Institute, an Energy Innovation Hub of the U.S. Department of Energy. Combinatoric studies of materials involve the creation of samples with varying composition, allowing the researcher to find the optimum combination of elements to produce a desired set of properties. The method has

  14. Synthesis of functional materials in combustion reactions

    SciTech Connect (OSTI)

    Zhuravlev, V. D. Bamburov, V. G.; Ermakova, L. V.; Lobachevskaya, N. I.

    2015-12-15

    The conditions for obtaining oxide compounds in combustion reactions of nitrates of metals with organic chelating–reducing agents such as amino acids, urea, and polyvinyl alcohol are reviewed. Changing the nature of internal fuels and the reducing agent-to-oxidizing agent ratio makes possible to modify the thermal regime of the process, fractal dimensionality, morphology, and dispersion of synthesized functional materials. This method can be used to synthesize simple and complex oxides, composites, and metal powders, as well as ceramics and coatings. The possibilities of synthesis in combustion reactions are illustrated by examples of αand γ-Al{sub 2}O{sub 3}, YSZ composites, uranium oxides, nickel powder, NiO and NiO: YSZ composite, TiO{sub 2}, and manganites, cobaltites, and aluminates of rare earth elements.

  15. Manufacturing Demonstration Facility: Low Temperature Materials Synthesis

    SciTech Connect (OSTI)

    Graham, David E.; Moon, Ji-Won; Armstrong, Beth L.; Datskos, Panos G.; Duty, Chad E.; Gresback, Ryan; Ivanov, Ilia N.; Jacobs, Christopher B.; Jellison, Gerald Earle; Jang, Gyoung Gug; Joshi, Pooran C.; Jung, Hyunsung; Meyer, III, Harry M.; Phelps, Tommy

    2015-06-30

    The Manufacturing Demonstration Facility (MDF) low temperature materials synthesis project was established to demonstrate a scalable and sustainable process to produce nanoparticles (NPs) for advanced manufacturing. Previous methods to chemically synthesize NPs typically required expensive, high-purity inorganic chemical reagents, organic solvents and high temperatures. These processes were typically applied at small laboratory scales at yields sufficient for NP characterization, but insufficient to support roll-to-roll processing efforts or device fabrication. The new NanoFermentation processes described here operated at a low temperature (~60 C) in low-cost, aqueous media using bacteria that produce extracellular NPs with controlled size and elemental stoichiometry. Up-scaling activities successfully demonstrated high NP yields and quality in a 900-L pilot-scale reactor, establishing this NanoFermentation process as a competitive biomanufacturing strategy to produce NPs for advanced manufacturing of power electronics, solid-state lighting and sensors.

  16. Self-assembly molecular squares with metal complexes as bridging ligands

    SciTech Connect (OSTI)

    Sun, S.S.; Silva, A.S.; Brinn, I.M.; Lees, A.J.

    2000-04-03

    Polynuclear transition metal complexes containing multichromophoric units, such as metal polypyridyl complexes, are of considerable current interest. Much attention has been paid to the synthesis of multicomponent systems that exhibit photoinduced intercomponent electron and/or energy-transfer processes and to their potential applications for photonic and electronic devices. Systems incorporating Re(I)- Ru(II)-, and Os(II)-based polypyridyl chromophores are the most commonly studied because of their favorable redox and spectroscopic characteristics. In this communication, the authors combine the concepts of self-assembly and complexes as ligands and report the preparation of a series of molecular squares with the general molecular formula [fac-Br(CO){sub 3}Re({mu}-(pyterpy){sub 2}M)]{sub 4}(PF{sub 6}){sub 8}, where pyterpy is 4{prime}-(4{prime}{double_prime}-pyridyl)-2,2{prime}:6{prime}2{double_prime}-terpyridine and M = Fe, Ru, or Os. The spectroscopic properties and a preliminary anion binding study of these novel octanuclear molecular squares are also presented.

  17. Self-Assembly by Instruction: Designing Nanoscale Systems Using DNA-Based Approaches (474th Brookhaven Lecture)

    SciTech Connect (OSTI)

    Gang, Oleg

    2012-01-18

    In the field of nanoscience, if you can control how nanoparticles self-assemble in particular structures — joining each other, for example, as molecules can form, atom-by-atom — you can design new materials that have unique properties that industry needs. Nature already uses the DNA genetic code to instruct the building of specific proteins and whole organisms in both plants and people. Taking a cue from nature, scientists at BNL devised a way of using strands of synthetic DNA attached to the surface of nanoparticles to instruct them to self-assemble into specific nanoscale structures, clusters, and three-dimensional organizations. Novel materials designed and fabricated this way promise use in photovoltaics, energy storage, catalysis, cell-targeted systems for more effective medical treatments, and biomolecular sensing for environmental monitoring and medical applications. To find out more about the rapid evolution of this nanoassembly method and its applications, join Physicist Oleg Gang of the Center for Functional Nanomaterials (CFN) as he gives the 474th Brookhaven Lecture, titled “Self-Assembly by Instruction: Designing Nanoscale Systems Using DNA-Based Approaches." Gang, who has led this work at the CFN, will explain the rapid evolution of this nanoassembly method, and discuss its present and future applications in highly specific biosensors, optically active nano-materials, and new ways to fabricate complex architectures in a rational manner via self-assembly. Gang and his colleagues used the CFN and the National Synchrotron Light Source (NSLS) facilities to perform their groundbreaking research. At the CFN, the scientists used electron microscopes and optical methods to visualize the clusters that they fabricated. At the NSLS, they applied x-rays to study a particles-assembly process in solution, DNA’s natural environment. Gang earned a Ph.D. in soft matter physics from Bar-Ilan University in 2000, and he was a Rothschild Fellow at Harvard

  18. Lubrication of polysilicon micromechanisms with self-assembled monolayers

    SciTech Connect (OSTI)

    Srinivasan, U.; Foster, J.D.; Habib, U.; Howe, R.T.; Maboudian, R.; Senft, D.C.; Dugger, M.T.

    1998-06-01

    Here, the authors report on the lubricating effects of self-assembled monolayers (SAMs) on MEMS by measuring static and dynamic friction with two polysilicon surface- micromachined devices. The first test structure is used to study friction between laterally sliding surfaces and with the second, friction between vertical sidewalls can be investigated. Both devices are SAM-coated following the sacrificial oxide etch and the microstructures emerge released and dry from the final water rinse. The coefficient of static friction, {mu}{sub s} was found to decrease from 2.1 {+-} 0.8 for the SiO{sub 2} coating to 0.11 {+-} 0.01 and 0.10 {+-} 0.01 for films derived from octadecyltrichloro-silane (OTS) and 1H,1H,2H,2H-perfluorodecyl-trichlorosilane (FDTS). Both OTS and FDTS SAM-coated structures exhibit dynamic coefficients of friction, {mu}{sub d} of 0.08 {+-} 0.01. These values were found to be independent of the apparent contact area, and remain unchanged after 1 million impacts at 5.6 {micro}N (17 kPa), indicating that these SAMs continue to act as boundary lubricants despite repeated impacts. Measurements during sliding friction from the sidewall friction testing structure give comparable initial {mu}{sub d} values of 0.02 at a contact pressure of 84 MPa. After 15 million wear cycles, {mu}{sub d} was found to rise to 0.27. Wear of the contacting surfaces was examined by SEM. Standard deviations in the {mu} data for SAM treatments indicate uniform coating coverage.

  19. Molecular behavior of DNA origami in higher order self-assembly

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

    Molecular behavior of DNA origami in higher order self-assembly Authors: Li, Z., Liu, M., Wang, L., Nangreave, J., Yan, H., and Liu, Y. Title: Molecular behavior of DNA origami in...

  20. DNA origami: A quantum leap for self assembly of complex structures

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

    DNA origami: A quantum leap for self assembly of complex structures Authors: Trring, T., Voigt, N.V., Nangreave, J., Yan, H., and Gothelf, K.V. Title: DNA origami: A quantum leap...

  1. Fragmentation dynamics of CS22+ on collision with a self assembled...

    Office of Scientific and Technical Information (OSTI)

    Surface-induced dissociation of doubly charged CS22+ ions in collision with a self assembled monolayer surface of fluorinated alkyl thiol on gold 111 crystal has been studied on a ...

  2. Self-Assembled, Nanostructured Carbon for Energy Storage and...

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

    January 2011 Development of High Capacity Anode for Li-ion Batteries Synthesis and Characterization of Structured Si-Carbon Nanocomposite Anodes and Functional Polymer Binders

  3. The mechanisms for nanoparticle surface diffusion and chain self-assembly determined from real-time nanoscale kinetics in liquid

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

    Woehl, Taylor J.; Prozorov, Tanya

    2015-08-20

    The mechanisms for nanoparticle self-assembly are often inferred from the morphology of the final nanostructures in terms of attractive and repulsive interparticle interactions. Understanding how nanoparticle building blocks are pieced together during self-assembly is a key missing component needed to unlock new strategies and mechanistic understanding of this process. Here we use real-time nanoscale kinetics derived from liquid cell transmission electron microscopy investigation of nanoparticle self-assembly to show that nanoparticle mobility dictates the pathway for self-assembly and final nanostructure morphology. We describe a new method for modulating nanoparticle diffusion in a liquid cell, which we employ to systematically investigate themore » effect of mobility on self-assembly of nanoparticles. We interpret the observed diffusion in terms of electrostatically induced surface diffusion resulting from nanoparticle hopping on the liquid cell window surface. Slow-moving nanoparticles self-assemble predominantly into linear 1D chains by sequential attachment of nanoparticles to existing chains, while highly mobile nanoparticles self-assemble into chains and branched structures by chain–chain attachments. Self-assembly kinetics are consistent with a diffusion-driven mechanism; we attribute the change in self-assembly pathway to the increased self-assembly rate of highly mobile nanoparticles. Furthermore, these results indicate that nanoparticle mobility can dictate the self-assembly mechanism and final nanostructure morphology in a manner similar to interparticle interactions.« less

  4. The mechanisms for nanoparticle surface diffusion and chain self-assembly determined from real-time nanoscale kinetics in liquid

    SciTech Connect (OSTI)

    Woehl, Taylor J.; Prozorov, Tanya

    2015-08-20

    The mechanisms for nanoparticle self-assembly are often inferred from the morphology of the final nanostructures in terms of attractive and repulsive interparticle interactions. Understanding how nanoparticle building blocks are pieced together during self-assembly is a key missing component needed to unlock new strategies and mechanistic understanding of this process. Here we use real-time nanoscale kinetics derived from liquid cell transmission electron microscopy investigation of nanoparticle self-assembly to show that nanoparticle mobility dictates the pathway for self-assembly and final nanostructure morphology. We describe a new method for modulating nanoparticle diffusion in a liquid cell, which we employ to systematically investigate the effect of mobility on self-assembly of nanoparticles. We interpret the observed diffusion in terms of electrostatically induced surface diffusion resulting from nanoparticle hopping on the liquid cell window surface. Slow-moving nanoparticles self-assemble predominantly into linear 1D chains by sequential attachment of nanoparticles to existing chains, while highly mobile nanoparticles self-assemble into chains and branched structures by chain–chain attachments. Self-assembly kinetics are consistent with a diffusion-driven mechanism; we attribute the change in self-assembly pathway to the increased self-assembly rate of highly mobile nanoparticles. Furthermore, these results indicate that nanoparticle mobility can dictate the self-assembly mechanism and final nanostructure morphology in a manner similar to interparticle interactions.

  5. 2012 BIOINSPIRED MATERIALS GORDON RESEARCH CONFERENCE, JUNE 24-29, 2012

    SciTech Connect (OSTI)

    Chilkoti, Ashutosh

    2013-06-29

    The emerging, interdisciplinary field of Bioinspired Materials focuses on developing a fundamental understanding of the synthesis, directed self-assembly and hierarchical organization of natural occurring materials, and uses this understanding to engineer new bioinspired artificial materials for diverse applications. The inaugural 2012 Gordon Conference on Bioinspired Materials seeks to capture the excitement of this burgeoning field by a cutting-edge scientific program and roster of distinguished invited speakers and discussion leaders who will address the key issues in the field. The Conference will feature a wide range of topics, such as materials and devices from DNA, reprogramming the genetic code for design of new materials, peptide, protein and carbohydrate based materials, biomimetic systems, complexity in self-assembly, and biomedical applications of bioinspired materials.

  6. Effect of Chain Chirality on the Self-Assembly of Sickle Hemoglobin |

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

    Argonne Leadership Computing Facility Effect of Chain Chirality on the Self-Assembly of Sickle Hemoglobin Authors: Li, X., Caswell, B., Karniadakis, G.E. We present simulation results on the self-assembly behavior of sickle hemoglobin (HbS). A coarse-grained HbS model, which contains hydrophilic and hydrophobic particles explicitly, is constructed to match the structural properties and physical description of HbS. The hydrophobic interactions are shown to be necessary with chirality being

  7. Theoretical Study of the Initial Stages of Self-Assembly of a Carboxysome’s Facet

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

    Mahalik, J. P.; Brown, Kirsten A.; Cheng, Xiaolin; Fuentes-Cabrera, Miguel

    2016-02-24

    Bacterial microcompartments, BMCs, are organelles that exist within wide variety of bacteria and act as nanofactories. Among the different types of known BMCs, the carboxysome has been studied the most. The carboxysome plays an important role in the light-independent part of the photosynthesis process, where its icosahedral-like proteinaceous shell acts as a membrane that controls the transport of metabolites. Although a structural model exists for the carboxysome shell, it remains largely unknown how the shell proteins self-assemble. Understanding the self-assembly process can provide insights into how the shell affects the carboxysome s function and how it can be modified tomore » create new functionalities, such as artificial nanoreactors and artificial protein membranes. Here, we explain a theoretical framework that employs Monte Carlo simulations with a coarse-grain potential that reproduces well the atomistic potential of mean force; employing this framework, we are able to capture the initial stages of the 2D self-assembly of CcmK2 hexamers, a major protein-shell component of the carboxysome's facet. The simulations reveal that CcmK2 hexamers self-assemble into clusters that resemble what was seen experimentally in 2D layers. Further analysis of the simulation results suggests that the 2D self-assembly of carboxysome s facets is driven by a nucleation growth process, which in turn could play an important role in the hierarchical self- assembly of BMC shells in general.« less

  8. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    behavior, charge transport, spin dynamics, materials and chemistry by design, optics, synthesis (novel materials), synthesis (self-assembly), synthesis (scalable ...

  9. Directed nanoscale self-assembly of molecular wires interconnecting nodal points using Monte Carlo simulations

    SciTech Connect (OSTI)

    Boscoboinik, A. M.; Manzi, S. J.; Tysoe, W. T.; Pereyra, V. D.; Boscoboinik, J. A.

    2015-09-10

    The influence of directing agents in the self-assembly of molecular wires to produce two-dimensional electronic nanoarchitectures is studied here using a Monte Carlo approach to simulate the effect of arbitrarily locating nodal points on a surface, from which the growth of self-assembled molecular wires can be nucleated. This is compared to experimental results reported for the self-assembly of molecular wires when 1,4-phenylenediisocyanide (PDI) is adsorbed on Au(111). The latter results in the formation of (Au-PDI)n organometallic chains, which were shown to be conductive when linked between gold nanoparticles on an insulating substrate. The present study analyzes, by means of stochastic methods, the influence of variables that affect the growth and design of self-assembled conductive nanoarchitectures, such as the distance between nodes, coverage of the monomeric units that leads to the formation of the desired architectures, and the interaction between the monomeric units. As a result, this study proposes an approach and sets the stage for the production of complex 2D nanoarchitectures using a bottom-up strategy but including the use of current state-of-the-art top-down technology as an integral part of the self-assembly strategy.

  10. Directed nanoscale self-assembly of molecular wires interconnecting nodal points using Monte Carlo simulations

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

    Boscoboinik, A. M.; Manzi, S. J.; Tysoe, W. T.; Pereyra, V. D.; Boscoboinik, J. A.

    2015-09-10

    The influence of directing agents in the self-assembly of molecular wires to produce two-dimensional electronic nanoarchitectures is studied here using a Monte Carlo approach to simulate the effect of arbitrarily locating nodal points on a surface, from which the growth of self-assembled molecular wires can be nucleated. This is compared to experimental results reported for the self-assembly of molecular wires when 1,4-phenylenediisocyanide (PDI) is adsorbed on Au(111). The latter results in the formation of (Au-PDI)n organometallic chains, which were shown to be conductive when linked between gold nanoparticles on an insulating substrate. The present study analyzes, by means of stochasticmore » methods, the influence of variables that affect the growth and design of self-assembled conductive nanoarchitectures, such as the distance between nodes, coverage of the monomeric units that leads to the formation of the desired architectures, and the interaction between the monomeric units. As a result, this study proposes an approach and sets the stage for the production of complex 2D nanoarchitectures using a bottom-up strategy but including the use of current state-of-the-art top-down technology as an integral part of the self-assembly strategy.« less

  11. Argonne scientists design self-assembled "micro-robots" | Argonne...

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

    materials. These structures can assemble, disassemble, and reassemble autonomously or on command and will enable novel materials capable of multi-tasking and self-repair. "For us,...

  12. New self-assembly luminescent molecular triangle and square rhenium(I) complexes

    SciTech Connect (OSTI)

    Sun, S.S.; Lees, A.J.

    1999-09-20

    The design and study of well-arranged metal-containing macrocycles is one of the major current research areas in modern supramolecular chemistry. Apart from their particular structural features, supramolecular species formed by self-assembly of transition metals introduce many special functional properties such as luminescence, redox activity, and magnetism into the structure. More recently, transition metal based molecular squares have been synthesized by utilizing self-assembly of preorganized metal centers and pyridine-based bridging ligands. The 90{degree} bonding angles between ligands in transition metal complexes provide an attractive feature for constructing macrocyclic structures.

  13. Self-Assembled Colloidal Plasmonic Systems | MIT-Harvard Center for

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

    Excitonics Assembled Colloidal Plasmonic Systems February 8, 2011 at 3pm/36-428 Jonathan Fan Harvard University FanJ_000 abstract: The self-assembly of colloids is an alternative to top-down processing that enables the fabrication of nanostructures. I will show that self-assembled clusters of metal-dielectric spheres are the basis for nanophotonic structures. By tailoring the number and position of spheres in close-packed clusters, plasmon modes exhibiting strong magnetic and Fano-like

  14. Thermoelectric materials and methods for synthesis thereof

    DOE Patents [OSTI]

    Ren, Zhifeng; Zhang, Qinyong; Zhang, Qian; Chen, Gang

    2015-08-04

    Materials having improved thermoelectric properties are disclosed. In some embodiments, lead telluride/selenide based materials with improved figure of merit and mechanical properties are disclosed. In some embodiments, the lead telluride/selenide based materials of the present disclosure are p-type thermoelectric materials formed by adding sodium (Na), silicon (Si) or both to thallium doped lead telluride materials. In some embodiments, the lead telluride/selenide based materials are formed by doping lead telluride/selenides with potassium.

  15. Highly Flexible Self-Assembled V2O5 Cathodes Enabled by Conducting Diblock Copolymers

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

    An, Hyosung; Mike, Jared; Smith, Kendall A.; Swank, Lisa; Lin, Yen-Hao; L. Pesek, Stacy; Verduzco, Rafael; Lutkenhaus, Jodie L.

    2015-09-22

    Mechanically robust battery electrodes are desired for applications in wearable devices, flexible displays, and structural energy and power. In this regard, the challenge is to balance mechanical and electrochemical properties in materials that are inherently brittle. Here, we demonstrate a unique water-based self-assembly approach that incorporates a diblock copolymer bearing electron- and ion-conducting blocks, poly(3-hexylthiophene)-block-poly(ethyleneoxide) (P3HT-b-PEO), with V2O5 to form a flexible, tough, carbon-free hybrid battery cathode. V2O5 is a promising lithium intercalation material, but it remains limited by its poor conductivity and mechanical properties. Our approach leads to a unique electrode structure consisting of interlocking V2O5 layers glued togethermore » with micellar aggregates of P3HT-b-PEO, which results in robust mechanical properties, far exceeding the those obtained from conventional fluoropolymer binders. Only 5 wt % polymer is required to triple the flexibility of V2O5, and electrodes comprised of 10 wt % polymer have unusually high toughness (293 kJ/m3) and specific energy (530 Wh/kg), both higher than reduced graphene oxide paper electrodes. Furthermore, addition of P3HT-b-PEO enhances lithium-ion diffusion, eliminates cracking during cycling, and boosts cyclability relative to V2O5 alone. These results highlight the importance of tradeoffs between mechanical and electrochemical performance, where polymer content can be used to tune both aspects.« less

  16. Self-Assembled, Nanostructured Carbon for Energy Storage and...

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

    In the area of energy storage, the development of carbon nano- materials for improved ultracapacitors will enhance the com- mercial viability of renewable energy technologies such ...

  17. Guided Self-Assembly of Gold Thin Films

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

    ... It does not require chemical modification to any of the components in the composite system ... of many materials besides gold, making it well suited for scalable manufacturing. ...

  18. Guided Self-Assembly of Gold Thin Films

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

    of this new family of materials, but also the fabrication of a wide range of next-generation nanodevices including optical lenses and polarizers, memory storage,...

  19. Self-assembly of water-soluble nanocrystals

    DOE Patents [OSTI]

    Fan, Hongyou; Brinker, C. Jeffrey; Lopez, Gabriel P.

    2012-01-10

    A method for forming an ordered array of nanocrystals where a hydrophobic precursor solution with a hydrophobic core material in an organic solvent is added to a solution of a surfactant in water, followed by removal of a least a portion of the organic solvent to form a micellar solution of nanocrystals. A precursor co-assembling material, generally water-soluble, that can co-assemble with individual micelles formed in the micellar solution of nanocrystals can be added to this micellar solution under specified reaction conditions (for example, pH conditions) to form an ordered-array mesophase material. For example, basic conditions are used to precipitate an ordered nanocrystal/silica array material in bulk form and acidic conditions are used to form an ordered nanocrystal/silica array material as a thin film.

  20. Self-Assembled Biomimetic Nanostructured Anti-Reflection Coatings for Highly Efficient Crystalline Silicon Solar Cells

    SciTech Connect (OSTI)

    2009-04-01

    This factsheet describes a study that will further develop the structure-property relationship understanding and performance testing of biomimetic nanostructured ARCs produced by a robust templating nanofabrication platform that combines the simplicity and cost benefits of bottom-up self-assembly with the scalability and compatibility of top-down microfabrication.

  1. Materials synthesis at the CNM | Argonne National Laboratory

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

    Materials synthesis at the CNM Titiania Nanoparticles 1 of 5 Titiania Nanoparticles Molecular model of titania nanoparticles covalently bound to biological molecules at Argonne's Center for Nanoscale Materials. Image: Photo courtesy of Argonne National Laboratory Titiania Nanoparticles 1 of 5 Titiania Nanoparticles Molecular model of titania nanoparticles covalently bound to biological molecules at Argonne's Center for Nanoscale Materials. Image: Photo courtesy of Argonne National Laboratory SEM

  2. Self-Assembly of Nanorods in Ternary Mixtures: Promoting the...

    Office of Scientific and Technical Information (OSTI)

    Research Org: Energy Frontier Research Centers (EFRC); Polymer-Based Materials for Harvesting Solar Energy (PHaSE) Sponsoring Org: USDOE SC Office of Basic Energy Sciences (SC-22) ...

  3. Self-Assembled, Nanostructured Carbon for Energy Storage and Water

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

    | Department of Energy Investigation of a series of transition metal oxides and precious metal based catalysts for ammonia selective oxidation at low temperatures deer12_thrun.pdf (1.16 MB) More Documents & Publications Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon Adsorber Materials Vehicle Technologies Office Merit Review 2014: Catalyst Characterization (Agreement ID:9130) Project ID:18519

  4. NREL: Energy Storage - Battery Materials Synthesis

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

    The greater energy and power requirements and system integration demands of EDVs pose significant challenges to energy storage technologies. Making these materials durable enough ...

  5. New self-assembled nanocrystal micelles for biolabels and biosensors.

    SciTech Connect (OSTI)

    Tallant, David Robert; Wilson, Michael C. (University of New Mexico, Albuquerque, NM); Leve, Erik W. (University of New Mexico, Albuquerque, NM); Fan, Hongyou; Brinker, C. Jeffrey; Gabaldon, John (University of New Mexico, Albuquerque, NM); Scullin, Chessa (University of New Mexico, Albuquerque, NM)

    2005-12-01

    The ability of semiconductor nanocrystals (NCs) to display multiple (size-specific) colors simultaneously during a single, long term excitation holds great promise for their use in fluorescent bio-imaging. The main challenges of using nanocrystals as biolabels are achieving biocompatibility, low non-specific adsorption, and no aggregation. In addition, functional groups that can be used to further couple and conjugate with biospecies (proteins, DNAs, antibodies, etc.) are required. In this project, we invented a new route to the synthesis of water-soluble and biocompatible NCs. Our approach is to encapsulate as-synthesized, monosized, hydrophobic NCs within the hydrophobic cores of micelles composed of a mixture of surfactants and phospholipids containing head groups functionalized with polyethylene glycol (-PEG), -COOH, and NH{sub 2} groups. PEG provided biocompatibility and the other groups were used for further biofunctionalization. The resulting water-soluble metal and semiconductor NC-micelles preserve the optical properties of the original hydrophobic NCs. Semiconductor NCs emit the same color; they exhibit equal photoluminescence (PL) intensity under long-time laser irradiation (one week) ; and they exhibit the same PL lifetime (30-ns). The results from transmission electron microscopy and confocal fluorescent imaging indicate that water-soluble semiconductor NC-micelles are biocompatible and exhibit no aggregation in cells. We have extended the surfactant/lipid encapsulation techniques to synthesize water-soluble magnetic NC-micelles. Transmission electron microscopy results suggest that water-soluble magnetic NC-micelles exhibit no aggregation. The resulting NC-micelles preserve the magnetic properties of the original hydrophobic magnetic NCs. Viability studies conducted using yeast cells suggest that the magnetic nanocrystal-micelles are biocompatible. We have demonstrated, for the first time, that using external oscillating magnetic fields to manipulate

  6. Self-assembled molecular films incorporating a ligand

    DOE Patents [OSTI]

    Bednarski, Mark D.; Wilson, Troy E.; Mastandra, Mark S.

    1996-01-01

    Functionalized monomers are presented which can be used in the fabrication of molecular films for controlling adhesion, detection of receptor-ligand binding and enzymatic reactions; new coatings for lithography; and for semiconductor materials. The monomers are a combination of a ligand, a linker, optionally including a polymerizable group, and a surface attachment group. The processes and an apparatus for making films from these monomers, as well as methods of using the films are also provided.

  7. Self-assembled molecular films incorporating a ligand

    DOE Patents [OSTI]

    Bednarski, M.D.; Wilson, T.E.; Mastandra, M.S.

    1996-04-23

    Functionalized monomers are presented which can be used in the fabrication of molecular films for controlling adhesion, detection of receptor-ligand binding and enzymatic reactions; new coatings for lithography; and for semiconductor materials. The monomers are a combination of a ligand, a linker, optionally including a polymerizable group, and a surface attachment group. The processes and an apparatus for making films from these monomers, as well as methods of using the films are also provided. 7 figs.

  8. Synthesis and design of silicide intermetallic materials

    SciTech Connect (OSTI)

    Petrovic, J.J.; Castro, R.G.; Butt, D.P.; Park, Y.; Hollis, K.J.; Kung, H.H.

    1998-11-01

    The overall objective of this program is to develop structural silicide-based materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation and corrosion resistance for applications of importance to the U.S. processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature materials and important applications in major energy-intensive U.S. processing industries.

  9. Secondary battery material and synthesis method

    DOE Patents [OSTI]

    Liu, Hongjian; Kepler, Keith Douglas; Wang, Yu

    2013-10-22

    A composite Li.sub.1+xMn.sub.2-x-yM.sub.yO.sub.4 cathode material stabilized by treatment with a second transition metal oxide phase that is highly suitable for use in high power and energy density Li-ion cells and batteries. A method for treating a Li.sub.1+xMn.sub.2-x-yM.sub.yO.sub.4 cathode material utilizing a dry mixing and firing process.

  10. Synthesis of thin films and materials utilizing a gaseous catalyst

    DOE Patents [OSTI]

    Morse, Daniel E; Schwenzer, Birgit; Gomm, John R; Roth, Kristian M; Heiken, Brandon; Brutchey, Richard

    2013-10-29

    A method for the fabrication of nanostructured semiconducting, photoconductive, photovoltaic, optoelectronic and electrical battery thin films and materials at low temperature, with no molecular template and no organic contaminants. High-quality metal oxide semiconductor, photovoltaic and optoelectronic materials can be fabricated with nanometer-scale dimensions and high dopant densities through the use of low-temperature biologically inspired synthesis routes, without the use of any biological or biochemical templates.

  11. Nanostructured columnar heterostructures of TiO{sub 2} and Cu{sub 2}O enabled by a thin-film self-assembly approach: Potential for photovoltaics

    SciTech Connect (OSTI)

    Polat, zgr; Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN 37996 ; Aytug, Tolga; Lupini, Andrew R.; Paranthaman, Parans M.; Ertugrul, Mehmet; Bogorin, Daniela F.; Meyer, Harry M.; Wang, Wei; Pennycook, Stephen J.; Christen, David K.

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ? Material self-assembly in phase-separated oxides is exploited. ? Three-dimensionally nanostructured epitaxial films are grown using sputtering. ? Films are composed of well-ordered oriented nanopillars of n-type TiO{sub 2} and p-type Cu{sub 2}O. ? Observed interfaces at adjacent TiO{sub 2}Cu{sub 2}O columns are nearly atomically distinct. ? Absorption profile of the composite film captures a wide range of the solar spectrum. -- Abstract: Significant efforts are being devoted to the development of multifunctional thin-film heterostructures and nanostructured material architectures for components with novel applications of superconductivity, multiferroicity, solar photocatalysis and energy conversion. In particular, nanostructured assemblies with well-defined geometrical shapes have emerged as possible high efficiency and economically viable alternatives to planar photovoltaic thin-film architectures. By exploiting phase-separated self-assembly, here we present advances in a vertically oriented two-component system that offers potential for future development of nanostructured thin film solar cells. Through a single-step deposition by magnetron sputtering, we demonstrate growth of an epitaxial, composite film matrix formed as self-assembled, well ordered, phase segregated, and oriented nanopillars of n-type TiO{sub 2} and p-type Cu{sub 2}O. The composite films were structurally characterized to atomic resolution by a variety of analytical tools, and evaluated for preliminary optical properties using absorption measurements. We find nearly atomically distinct TiO{sub 2}Cu{sub 2}O interfaces (i.e., needed for possible active pn junctions), and an absorption profile that captures a wide range of the solar spectrum extending from ultraviolet to visible wavelengths. This high-quality materials system could lead to photovoltaic devices that can be optimized for both incident light absorption and carrier collection.

  12. Synthesis of Two-Dimensional Materials by Selective Extraction

    SciTech Connect (OSTI)

    Naguib, Michael; Gogotsi, Yury

    2014-12-09

    Two-dimensional (2D) materials have attracted much attention in the past decade. They offer high specific surface area, as well as electronic structure and properties that differ from their bulk counterparts due to the low dimensionality. Graphene is the best known and the most studied 2D material, but metal oxides and hydroxides (including clays), dichalcogenides, boron nitride (BN), and other materials that are one or several atoms thick are receiving increasing attention. They may deliver a combination of properties that cannot be provided by other materials. The most common synthesis approach in general is by reacting different elements or compounds to form a new compound. However, this approach does not necessarily work well for low-dimensional structures, since it favors formation of energetically preferred 3D (bulk) solids. Many 2D materials are produced by exfoliation of van der Waals solids, such as graphite or MoS2, breaking large particles into 2D layers. However, these approaches are not universal; for example, 2D transition metal carbides cannot be produced by any of them. An alternative but less studied way of material synthesis is the selective extraction process, which is based on the difference in reactivity and stability between the different components (elements or structural units) of the original material. It can be achieved using thermal, chemical, or electrochemical processes. Many 2D materials have been synthesized using selective extraction, such as graphene from SiC, transition metal oxides (TMO) from layered 3D salts, and transition metal carbides or carbonitrides (MXenes) from MAX phases. Selective extraction synthesis is critically important when the bonds between the building blocks of the material are too strong (e.g., in carbides) to be broken mechanically in order to form nanostructures. Unlike extractive metallurgy, where the extracted metal is the goal of the process, selective extraction of one or more elements from the precursor

  13. Synthesis of Two-Dimensional Materials by Selective Extraction

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

    Naguib, Michael; Gogotsi, Yury

    2014-12-09

    Two-dimensional (2D) materials have attracted much attention in the past decade. They offer high specific surface area, as well as electronic structure and properties that differ from their bulk counterparts due to the low dimensionality. Graphene is the best known and the most studied 2D material, but metal oxides and hydroxides (including clays), dichalcogenides, boron nitride (BN), and other materials that are one or several atoms thick are receiving increasing attention. They may deliver a combination of properties that cannot be provided by other materials. The most common synthesis approach in general is by reacting different elements or compounds tomore » form a new compound. However, this approach does not necessarily work well for low-dimensional structures, since it favors formation of energetically preferred 3D (bulk) solids. Many 2D materials are produced by exfoliation of van der Waals solids, such as graphite or MoS2, breaking large particles into 2D layers. However, these approaches are not universal; for example, 2D transition metal carbides cannot be produced by any of them. An alternative but less studied way of material synthesis is the selective extraction process, which is based on the difference in reactivity and stability between the different components (elements or structural units) of the original material. It can be achieved using thermal, chemical, or electrochemical processes. Many 2D materials have been synthesized using selective extraction, such as graphene from SiC, transition metal oxides (TMO) from layered 3D salts, and transition metal carbides or carbonitrides (MXenes) from MAX phases. Selective extraction synthesis is critically important when the bonds between the building blocks of the material are too strong (e.g., in carbides) to be broken mechanically in order to form nanostructures. Unlike extractive metallurgy, where the extracted metal is the goal of the process, selective extraction of one or more elements from the

  14. Synthesis of Two-Dimensional Materials by Selective Extraction

    SciTech Connect (OSTI)

    Abdelmalak, Michael Naguib; Gogotsi, Yury

    2015-01-01

    Two-dimensional (2D) materials have attracted much attention in the past decade. They offer high specific surface area, as well as electronic structure and properties that differ from their bulk counterparts due to the low dimensionality. Graphene is the best known and the most studied 2D material, but metal oxides and hydroxides (including clays), dichalcogenides, boron nitride (BN), and other materials that are one or several atoms thick are receiving increasing attention. They may deliver a combination of properties that cannot be provided by other materials. The most common synthesis approach in general is by reacting different elements or compounds to form a new compound. However, this approach does not necessarily work well for low-dimensional structures, since it favors formation of energetically preferred 3D (bulk) solids. Many 2D materials are produced by exfoliation of van der Waals solids, such as graphite or MoS2, breaking large particles into 2D layers. However, these approaches are not universal; for example, 2D transition metal carbides cannot be produced by any of them. An alternative but less studied way of material synthesis is the selective extraction process, which is based on the difference in reactivity and stability between the different components (elements or structural units) of the original material. It can be achieved using thermal, chemical, or electrochemical processes. Many 2D materials have been synthesized using selective extraction, such as graphene from SiC, transition metal oxides (TMO) from layered 3D salts, and transition metal carbides or carbonitrides (MXenes) from MAX phases. Selective extraction synthesis is critically important when the bonds between the building blocks of the material are too strong (e.g., in carbides) to be broken mechanically in order to form nanostructures. Unlike extractive metallurgy, where the extracted metal is the goal of the process, selective extraction of one or more elements from the precursor

  15. One-step fabrication of free-standing flexible membranes reinforced with self-assembled arrays of carbon nanotubes

    SciTech Connect (OSTI)

    Grilli, S.; Coppola, S.; Vespini, V.; Pagliarulo, V.; Ferraro, P.; Nasti, G.; Carfagna, C.

    2014-10-13

    Here, we report on a single step approach for fabricating free-standing polymer membranes reinforced with arrayed self-assembled carbon nanotubes (CNTs). The CNTs are self-assembled spontaneously by electrode-free DC dielectrophoresis based on surface charge templates. The electrical charge template is generated through the pyroelectric effect onto periodically poled lithium niobate ferroelectric crystals. A thermal stimulus enables simultaneously the self-assembly of the CNTs and the cross-linking of the host polymer. Examples of thin polydimethylsiloxane membranes reinforced with CNT patterns are shown.

  16. Structural and optical properties of self-assembled chains of plasmonic nanocubes

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

    Klinkova, Anna; Gang, Oleg; Therien-Aubin, Heloise; Ahmed, Aftab; Nykypanchuk, Dmytro; Choueiri, Rachelle M.; Gagnon, Brandon; Muntyanu, Anastasiya; Walker, Gilbert C.; Kumacheva, Eugenia

    2014-10-10

    Solution-based linear self-assembly of metal nanoparticles offers a powerful strategy for creating plasmonic polymers, which, so far, have been formed from spherical nanoparticles and nanorods. Here, we report linear solution-based self-assembly of metal nanocubes (NCs), examine the structural characteristics of the NC chains and demonstrate their advanced optical characteristics. Predominant face-to-face assembly of large NCs coated with short polymer ligands led to a larger volume of hot spots in the chains, a nearly uniform E-field enhancement in the gaps between co-linear NCs and a new coupling mode for NC chains, in comparison with chains of nanospheres with similar dimensions, compositionmore » and surface chemistry. The NC chains exhibited a stronger surface enhanced Raman scattering (SERS) signal, in comparison with linear assemblies of nanospheres. The experimental results were in agreement with finite difference time domain (FDTD) simulations.« less

  17. Structural and optical properties of self-assembled chains of plasmonic nanocubes

    SciTech Connect (OSTI)

    Klinkova, Anna; Gang, Oleg; Therien-Aubin, Heloise; Ahmed, Aftab; Nykypanchuk, Dmytro; Choueiri, Rachelle M.; Gagnon, Brandon; Muntyanu, Anastasiya; Walker, Gilbert C.; Kumacheva, Eugenia

    2014-10-10

    Solution-based linear self-assembly of metal nanoparticles offers a powerful strategy for creating plasmonic polymers, which, so far, have been formed from spherical nanoparticles and nanorods. Here, we report linear solution-based self-assembly of metal nanocubes (NCs), examine the structural characteristics of the NC chains and demonstrate their advanced optical characteristics. Predominant face-to-face assembly of large NCs coated with short polymer ligands led to a larger volume of hot spots in the chains, a nearly uniform E-field enhancement in the gaps between co-linear NCs and a new coupling mode for NC chains, in comparison with chains of nanospheres with similar dimensions, composition and surface chemistry. The NC chains exhibited a stronger surface enhanced Raman scattering (SERS) signal, in comparison with linear assemblies of nanospheres. The experimental results were in agreement with finite difference time domain (FDTD) simulations.

  18. Method of synthesis of proton conducting materials

    DOE Patents [OSTI]

    Garzon, Fernando Henry; Einsla, Melinda Lou; Mukundan, Rangachary

    2010-06-15

    A method of producing a proton conducting material, comprising adding a pyrophosphate salt to a solvent to produce a dissolved pyrophosphate salt; adding an inorganic acid salt to a solvent to produce a dissolved inorganic acid salt; adding the dissolved inorganic acid salt to the dissolved pyrophosphate salt to produce a mixture; substantially evaporating the solvent from the mixture to produce a precipitate; and calcining the precipitate at a temperature of from about 400.degree. C. to about 1200.degree. C.

  19. Intersubband absorption in CdSe/Zn{sub x}Cd{sub y}Mg{sub 1-x-y}Se self-assembled quantum dot multilayers

    SciTech Connect (OSTI)

    Shen, A.; Lu, H.; Charles, W.; Yokomizo, I.; Tamargo, M. C.; Franz, K. J.; Gmachl, C.; Zhang, S. K.; Zhou, X.; Alfano, R. R.; Liu, H. C.

    2007-02-12

    The authors report the observation of intersubband absorption in multilayers of CdSe/Zn{sub x}Cd{sub y}Mg{sub 1-x-y}Se self-assembled quantum dots. The samples were grown by molecular beam epitaxy on InP substrates. For samples with the CdSe dot layers doped with Cl and with the deposited CdSe equivalent layer thickness between 5.2 and 6.9 ML, peak absorption between 2.5 and 3.5 {mu}m was observed. These materials are promising for intersubband devices operating in the mid- and near-infrared ranges.

  20. A multi-stimuli responive, self-assembling, boronic acid dipeptide

    SciTech Connect (OSTI)

    Jones, Brad Howard; Martinez, Alina Marissa; Wheeler, Jill S.; McKenzie, Bonnie B.; Miller, Lance Lee; Wheeler, David R.; Spoerke, Erik David

    2015-08-11

    Modification of the dipeptide of phenylalanine, FF, with a boronic acid (BA) functionality imparts unique aqueous self-assembly behavior that responds to multiple stimuli. Changes in pH and ionic strength are used to trigger hydrogelation via the formation of nanoribbon networks. Thus, we show for the first time that the binding of polyols to the BA functionality can modulate a peptide between its assembled and disassembled states.

  1. Polymer arrays from the combinatorial synthesis of novel materials

    DOE Patents [OSTI]

    Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong

    2004-09-21

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  2. Small Angle Neutron Scattering (SANS) Studies on the Structural Evolution of Pyromellitamide Self-assembled Gels

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

    Scott, Jamieson; Tong, Katie; William, Hamilton; He, Lilin; James, Michael; Thordarson, Pall; Boukhalfa, Sofiane

    2014-10-31

    The kinetics of aggregation of two pyromellitamide gelators; tetrabutyl- (C4) and tetrahexylpyromellitamide (C6), in deuterated cyclohexane has been investigated by small angle neutron scattering (SANS) for up to six days. The purpose of this study was to improve our understanding of how self-assembled gels are formed. Short-term (< 3 hour) time scales revealed multiple phases with the data for the tetrabutylpyromellitamide C4 indicating one dimensional stacking and aggregation corresponding to a multi-fiber braided cluster arrangement that is about 35 Å in diameter. The corresponding tetrahexylpyromellitamide C6 data suggests that the C6 also forms one-dimensional stacks but that these aggregate tomore » a thicker multi-fiber braided cluster that have a diameter of 61.8 Å. Over a longer period of time, the radius, persistence length and contour length all continue to increase in 6 days after cooling. This data suggests that structural changes in self-assembled gels occur over a period exceeding several days and that fairly subtle changes in the structure (e.g. tail-length) can influence the packing of molecules in self-assembled gels on the single-to-few fiber bundle stage.« less

  3. Simulation and dynamics of entropy-driven, molecular self-assembly processes

    SciTech Connect (OSTI)

    Mayer, B.; Kohler, G.,; Rasmussen, S.,

    1997-04-01

    Molecular self-assembly is frequently found to generate higher-order functional structures in biochemical systems. One such example is the self-assembly of lipids in aqueous solution forming membranes, micelles, and vesicles; another is the dynamic formation and rearrangement of the cytoskeleton. These processes are often driven by local, short-range forces and therefore the dynamics is solely based on local interactions. In this paper, we introduce a cellular automata based simulation, the lattice molecular automaton, in which data structures, representing different molecular entities such as water and hydrophilic and hydrophobic monomers, share locally propagated force information on a hexagonal, two-dimensional lattice. The purpose of this level of description is the simulation of entropic and enthalpic flows in a microcanonical, molecular ensemble to gain insight about entropy-driven processes in molecular many-particle systems. Three applications are shown, i.e., modeling structural features of a polar solvent, cluster formation of hydrophobic monomers in a polar environment, and the self-assembly of polymers. Processes leading to phase separation on a molecular level are discussed. A thorough discussion of the computational details, advantages, and limitations of the lattice molecular automaton approach is given elsewhere [B. Mayer and S. Rasmussen (unpublished)]. {copyright} {ital 1997} {ital The American Physical Society}

  4. Organic molecules deposited on graphene: A computational investigation of self-assembly and electronic structure

    SciTech Connect (OSTI)

    Oliveira, I. S. S. de; Miwa, R. H.

    2015-01-28

    We use ab initio simulations to investigate the adsorption and the self-assembly processes of tetracyanoquinodimethane (TCNQ), tetrafluoro-tetracyanoquinodimethane (F4-TCNQ), and tetrasodium 1,3,6,8-pyrenetetrasulfonic acid (TPA) on the graphene surface. We find that there are no chemical bonds at the moleculegraphene interface, even at the presence of grain boundaries on the graphene surface. The molecules bond to graphene through van der Waals interactions. In addition to the moleculegraphene interaction, we performed a detailed study of the role played by the (lateral) moleculemolecule interaction in the formation of the, experimentally verified, self-assembled layers of TCNQ and TPA on graphene. Regarding the electronic properties, we calculate the electronic charge transfer from the graphene sheet to the TCNQ and F4-TCNQ molecules, leading to a p-doping of graphene. Meanwhile, such charge transfer is reduced by an order of magnitude for TPA molecules on graphene. In this case, it is not expected a significant doping process upon the formation of self-assembled layer of TPA molecules on the graphene sheet.

  5. Lower pressure synthesis of diamond material

    DOE Patents [OSTI]

    Lueking, Angela; Gutierrez, Humberto; Narayanan, Deepa; Burgess Clifford, Caroline E.; Jain, Puja

    2010-07-13

    Methods of synthesizing a diamond material, particularly nanocrystalline diamond, diamond-like carbon and bucky diamond are provided. In particular embodiments, a composition including a carbon source, such as coal, is subjected to addition of energy, such as high energy reactive milling, producing a milling product enriched in hydrogenated tetrahedral amorphous diamond-like carbon compared to the coal. A milling product is treated with heat, acid and/or base to produce nanocrystalline diamond and/or crystalline diamond-like carbon. Energy is added to produced crystalline diamond-like carbon in particular embodiments to produce bucky diamonds.

  6. SYNTHESIS AND CHARACTERIZATION OF ADVANCED MAGNETIC MATERIALS

    SciTech Connect (OSTI)

    Monica Sorescu

    2004-09-22

    The work described in this grant report was focused mainly on the properties of novel magnetic intermetallics. In the first project, we synthesized several 2:17 intermetallic compounds, namely Nd{sub 2}Fe{sub 15}Si{sub 2}, Nd{sub 2}Fe{sub 15}Al{sub 2}, Nd{sub 2}Fe{sub 15}SiAl and Nd{sub 2}Fe{sub 15}SiMn, as well as several 1:12 intermetallic compounds, such as NdFe{sub 10}Si{sub 2}, NdFe{sub 10}Al{sub 2}, NdFe{sub 10}SiAl and NdFe{sub 10}MnAl. In the second project, seven compositions of Nd{sub x}Fe{sub 100-x-y}B{sub y} ribbons were prepared by a melt spinning method with Nd and B content increasing from 7.3 and 3.6 to 11 and 6, respectively. The alloys were annealed under optimized conditions to obtain a composite material consisting of the hard magnetic Nd{sub 2}Fe{sub 14}B and soft magnetic {alpha}-Fe phases, typical of a spring magnet structure. In the third project, intermetallic compounds of the type Zr{sub 1}Cr{sub 1}Fe{sub 1}T{sub 0.8} with T = Al, Co and Fe were subjected to hydrogenation. In the fourth project, we performed three crucial experiments. In the first experiment, we subjected a mixture of Fe{sub 3}O{sub 4} and Fe (80-20 wt %) to mechanochemical activation by high-energy ball milling, for time periods ranging from 0.5 to 14 hours. In the second experiment, we ball-milled Fe{sub 3}O{sub 4}:Co{sup 2+} (x = 0.1) for time intervals between 2.5 and 17.5 hours. Finally, we exposed a mixture of Fe{sub 3}O{sub 4} and Co (80-20 wt %) to mechanochemical activation for time periods ranging from 0.5 to 10 hours. In all cases, the structural and magnetic properties of the systems involved were elucidated by X-ray diffraction (XRD), Moessbauer spectroscopy and hysteresis loop measurements. The four projects resulted in four papers, which were published in Intermetallics, IEEE Transactions on Magnetics, Journal of Materials Science Letters and Materials Chemistry and Physics. The contributions reveal for the first time in literature the effect of

  7. Cermet materials prepared by combustion synthesis and metal infiltration

    DOE Patents [OSTI]

    Holt, J.B.; Dunmead, S.D.; Halverson, D.C.; Landingham, R.L.

    1991-01-29

    Ceramic-metal composites (cermets) are made by a combination of self-propagating high temperature combustion synthesis and molten metal infiltration. Solid-gas, solid-solid and solid-liquid reactions of a powder compact produce a porous ceramic body which is infiltrated by molten metal to produce a composite body of higher density. AlN-Al and many other materials can be produced. 6 figures.

  8. Grained composite materials prepared by combustion synthesis under mechanical pressure

    DOE Patents [OSTI]

    Dunmead, Stephen D.; Holt, Joseph B.; Kingman, Donald D.; Munir, Zuhair A.

    1990-01-01

    Dense, finely grained composite materials comprising one or more ceramic phase or phase and one or more metallic and/or intermetallic phase or phases are produced by combustion synthesis. Spherical ceramic grains are homogeneously dispersed within the matrix. Methods are provided, which include the step of applying mechanical pressure during or immediately after ignition, by which the microstructures in the resulting composites can be controllably selected.

  9. Cermet materials prepared by combustion synthesis and metal infiltration

    DOE Patents [OSTI]

    Holt, Joseph B.; Dunmead, Stephen D.; Halverson, Danny C.; Landingham, Richard L.

    1991-01-01

    Ceramic-metal composites (cermets) are made by a combination of self-propagating high temperature combustion synthesis and molten metal infiltration. Solid-gas, solid-solid and solid-liquid reactions of a powder compact produce a porous ceramic body which is infiltrated by molten metal to produce a composite body of higher density. AlN-Al and many other materials can be produced.

  10. Catalytic Deprotection of Acetals In Strongly Basic Solution Usinga Self-Assembled Supramolecular 'Nanozyme'

    SciTech Connect (OSTI)

    Pluth, Michael D.; Bergman, Robert G.; Raymond, Kenneth N.

    2007-07-26

    Acetals are among the most commonly used protecting groups for aldehydes and ketones in organic synthesis due to their ease of installation and resistance to cleavage in neutral or basic solution.[1] The common methods for hydrolyzing acetals almost always involve the use of either Broensted acid or Lewis acid catalysts.[2] Usually aqueous acids or organic solutions acidified with organic or inorganic acids have been used for reconversion of the acetal functionality to the corresponding carbonyl group; however, recently a number of reports have documented a variety of strategies for acetal cleavage under mild conditions. These include the use of Lewis acids such as bismuth(III)[3] or cerium(IV),[4, 5] functionalized silica gel, such as silica sulfuric acid[6] or silica-supported pyridinium p-toluene sulfonate,[7] or the use of silicon-based reagents such as TESOTf-2,6-Lutidine.[8] Despite these mild reagents, all of the above conditions require either added acid or overall acidic media. Marko and co-workers recently reported the first example of acetal deprotection under mildly basic conditions using catalytic cerium ammonium nitrate at pH 8 in a water-acetonitrile solution.[5] Also recently, Rao and co-workers described a purely aqueous system at neutral pH for the deprotection of acetals using {beta}-cyclodextrin as the catalyst.[9] Herein, we report the hydrolysis of acetals in strongly basic aqueous solution using a self-assembled supramolecular host as the catalyst. During the last decade, we have used metal-ligand interactions for the formation of well-defined supramolecular assemblies with the stoichiometry M{sub 4}L{sub 6}6 (M = Ga{sup III} (1 refers to K{sub 12}[Ga{sub 4}L{sub 6}]), Al{sup III}, In{sup III}, Fe{sup III}, Ti{sup IV}, or Ge{sup IV}, L = N,N{prime}-bis(2,3-dihydroxybenzoyl)-1,5-diaminonaphthalene) (Figure 1).[10] The metal ions occupy the vertices of the tetrahedron and the bisbidentate catecholamide ligands span the edges. The strong

  11. Solar synthesis of advanced materials: A solar industrial program initiative

    SciTech Connect (OSTI)

    Lewandowski, A.

    1992-06-01

    This is an initiative for accelerating the use of solar energy in the advanced materials manufacturing industry in the United States. The initiative will be based on government-industry collaborations that will develop the technology and help US industry compete in the rapidly expanding global advanced materials marketplace. Breakthroughs in solar technology over the last 5 years have created exceptional new tools for developing advanced materials. Concentrated sunlight from solar furnaces can produce intensities that approach those on the surface of the sun and can generate temperatures well over 2000{degrees}C. Very thin layers of illuminated surfaces can be driven to remarkably high temperatures in a fraction of a second. Concentrated solar energy can be delivered over large areas, allowing for rapid processing and high production rates. By using this technology, researchers are transforming low-cost raw materials into high-performance products. Solar synthesis of advanced materials uses bulk materials and energy more efficiently, lowers processing costs, and reduces the need for strategic materials -- all with a technology that does not harm the environment. The Solar Industrial Program has built a unique, world class solar furnace at NREL to help meet the growing need for applied research in advanced materials. Many new advanced materials processes have been successfully demonstrated in this facility, including the following: Metalorganic deposition, ceramic powders, diamond-like carbon materials, rapid heat treating, and cladding (hard coating).

  12. Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors

    SciTech Connect (OSTI)

    Hu, Michael Z.; Lai, Peng

    2015-01-01

    Nanoporous silica wires of various wire diameters were developed by space-confined molecular self-assembly of triblock copolymer ethylene/propylene/ethylene (P123) and silica alkoxide precursor (tetraethylorthosilicate, TEOS). Two distinctive hard-templating substrates, anodized aluminum oxide (AAO) and track-etched polycarbonate (EPC), with channel diameters in the range between 10 nm and 200 nm were employed for space-confinement of soft molecular self-assembly driven by the block-copolymer microphase separation. It was observed in the scanning and transmission electron microscope (STEM) studies that the substrate geometry and material characteristics had pronounced effects on the structure and morphology of the silica nanowires. A substrate wall effect was proposed to explain the ordering and orientation of the intra-wire mesostructure. Circular and spiral nanostructures were found only in wires formed in AAO substrate, not in EPC. Pore-size differences and distinctive wall morphologies of the nanowires relating to the substrates were discussed. It was shown that the material and channel wall characteristics of different substrates play key roles in the ordering and morphology of the intra-wire nanostructures.

  13. Substrate effect on nanoporous structure of silica wires by channel-confined self-assembly of block-copolymer and sol-gel precursors

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

    Hu, Michael Z.; Lai, Peng

    2015-01-01

    Nanoporous silica wires of various wire diameters were developed by space-confined molecular self-assembly of triblock copolymer ethylene/propylene/ethylene (P123) and silica alkoxide precursor (tetraethylorthosilicate, TEOS). Two distinctive hard-templating substrates, anodized aluminum oxide (AAO) and track-etched polycarbonate (EPC), with channel diameters in the range between 10 nm and 200 nm were employed for space-confinement of soft molecular self-assembly driven by the block-copolymer microphase separation. It was observed in the scanning and transmission electron microscope (STEM) studies that the substrate geometry and material characteristics had pronounced effects on the structure and morphology of the silica nanowires. A substrate wall effect was proposed tomore » explain the ordering and orientation of the intra-wire mesostructure. Circular and spiral nanostructures were found only in wires formed in AAO substrate, not in EPC. Pore-size differences and distinctive wall morphologies of the nanowires relating to the substrates were discussed. It was shown that the material and channel wall characteristics of different substrates play key roles in the ordering and morphology of the intra-wire nanostructures.« less

  14. Simulation of macromolecule self-assembly in solution: A multiscale approach

    SciTech Connect (OSTI)

    Lavino, Alessio D. Barresi, Antonello A. Marchisio, Daniele L.; Pasquale, Nicodemo di; Carbone, Paola

    2015-12-17

    One of the most common processes to produce polymer nanoparticles is to induce self-assembly by using the solvent-displacement method, in which the polymer is dissolved in a “good” solvent and the solution is then mixed with an “anti-solvent”. The polymer ability to self-assemble in solution is therefore determined by its structural and transport properties in solutions of the pure solvents and at the intermediate compositions. In this work, we focus on poly-ε-caprolactone (PCL) which is a biocompatible polymer that finds widespread application in the pharmaceutical and biomedical fields, performing simulation at three different scales using three different computational tools: full atomistic molecular dynamics (MD), population balance modeling (PBM) and computational fluid dynamics (CFD). Simulations consider PCL chains of different molecular weight in solution of pure acetone (good solvent), of pure water (anti-solvent) and their mixtures, and mixing at different rates and initial concentrations in a confined impinging jets mixer (CIJM). Our MD simulations reveal that the nano-structuring of one of the solvents in the mixture leads to an unexpected identical polymer structure irrespectively of the concentration of the two solvents. In particular, although in pure solvents the behavior of the polymer is, as expected, very different, at intermediate compositions, the PCL chain shows properties very similar to those found in pure acetone as a result of the clustering of the acetone molecules in the vicinity of the polymer chain. We derive an analytical expression to predict the polymer structural properties in solution at different solvent compositions and use it to formulate an aggregation kernel to describe the self-assembly in the CIJM via PBM and CFD. Simulations are eventually validated against experiments.

  15. Enzymatic Ligation Creates Discrete Multi-Nanoparticle Building Blocks for Self-Assembly

    SciTech Connect (OSTI)

    Claridge, Shelley A.; Mastroianni, Alexander J.; Au, Yeung B.; Liang, Huiyang W.; Micheel, Christine M.; Frechet, Jean M.J.; Alivisatos, A. Paul

    2008-05-27

    Enzymatic ligation of discrete nanoparticle?DNA conjugates creates nanoparticle dimer and trimer structures in which the nanoparticles are linked by single-stranded DNA, rather than double-stranded DNA as in previous experiments. Ligation is verified by agarose gel and small-angle X-ray scattering. This capability is utilized in two ways: first to create a new class of multiparticle building blocks for nanoscale self-assembly; second to develop a system which can amplify a population of discrete nanoparticle assemblies.

  16. Method for selective immobilization of macromolecules on self assembled monolayer surfaces

    DOE Patents [OSTI]

    Laskin, Julia; Wang, Peng

    2011-11-29

    Disclosed is a method for selective chemical binding and immobilization of macromolecules on solid supports in conjunction with self-assembled monolayer (SAM) surfaces. Immobilization involves selective binding of peptides and other macromolecules to SAM surfaces using reactive landing (RL) of mass-selected, gas phase ions. SAM surfaces provide a simple and convenient platform for tailoring chemical properties of a variety of substrates. The invention finds applications in biochemistry ranging from characterization of molecular recognition events at the amino acid level and identification of biologically active motifs in proteins, to development of novel biosensors and substrates for stimulated protein and cell adhesion.

  17. Poly(ethylene oxide)-Assisted Macromolecular Self-Assembly of Lignin in ABS Matrix for Sustainable Composite Applications

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

    Akato, Kokouvi M.; Tran, Chau D.; Chen, Jihua; Naskar, Amit K.

    2015-11-05

    Here we report the compatibilization of biomass-derived lignin polymer in acrylonitrile butadiene styrene (ABS) thermoplastic matrix without loss of mechanical properties via poly(ethylene oxide) (PEO)-mediated macromolecular self-assembly. ABS was blended with lignin in different concentrations, and blends with 10 wt % PEO (relative to lignin) were prepared. The relative tensile strength improved slightly at low lignin content but diminished rapidly as the lignin content was increased. However, the inclusion of PEO as an interfacial adhesion promoter helped avoid deleterious effects. Dynamic mechanical analysis showed that PEO plasticized the hard phase and thus lowered the activation energy (Ea) for its relaxationmore » but caused stiffening of the soft phase and increased its Ea. Microscopy revealed that incorporating lignin in ABS led to the statistical dispersion of discrete lignin domains (300–1000 nm) which, after PEO addition, were reduced to smaller interconnected particles (200–500 nm). The lignin-extended partially renewable ABS resins showed shear-thinning behavior and reduced viscosity compared to neat ABS. The preferred lignin-loaded compositions reinforced with 20 vol % chopped carbon fibers exhibited mechanical performances (77–80 MPa) equivalent to those of reinforced ABS materials reportedly used in 3D printing applications. In conclusion, this approach could lower the cost of ABS while reducing its carbon footprint.« less

  18. Covalent Immobilization of Peptides on Self-Assembled Monolayer Surfaces Using Soft-Landing of Mass-Selected Ions

    SciTech Connect (OSTI)

    Wang, Peng; Hadjar, Omar; Laskin, Julia

    2007-06-23

    Covalent immobilization of peptides on solid supports plays an important role in biochemistry with applications ranging from characterization of molecular recognition events at the amino acid level and identification of biologically active motifs in proteins to development of novel biosensors and substrates for improved cell adhesion. Self-assembled monolayer surfaces (SAMs) provide a simple and convenient platform for tailoring chemical properties of a variety of substrates. Existing techniques for linking peptides to SAMs are based on solution-phase synthetic strategies and require relatively large quantities of purified material. Here, we report a novel approach for highly selective covalent binding of peptides to SAMs using soft-landing (SL) of mass-selected ions. SL is defined as intact deposition of ions onto suitable substrates at hyperthermal (<100 eV) energies.Recent studies have demonstrated that SAMs are excellent deposition targets for SL due to their ability to dissipate kinetic energies of the projectiles and their efficiency in trapping captured species. It has been proposed that SL could be utilized for controlled preparation of protein arrays.

  19. Superconductivity in epitaxially grown self-assembled indium islands: progress towards hybrid superconductor/semiconductor optical sources

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

    Gehl, Michael; Gibson, Ricky; Zandbergen, Sander; Keiffer, Patrick; Sears, Jasmine; Khitrova, Galina

    2016-02-01

    Currently, superconducting qubits lead the way in potential candidates for quantum computing. This is a result of the robust nature of superconductivity and the non-linear Josephson effect which make possible many types of qubits. At the same time, transferring quantum information over long distances typically relies on the use of photons as the elementary qubit. Converting between stationary electronic qubits in superconducting systems and traveling photonic qubits is a challenging yet necessary goal for the interface of quantum computing and communication. The most promising path to achieving this goal appears to be the integration of superconductivity with optically active semiconductors,more » with quantum information being transferred between the two by means of the superconducting proximity effect. Obtaining good interfaces between superconductor and semiconductor is the next obvious step for improving these hybrid systems. As a result, we report on our observation of superconductivity in self-assembled indium structures grown epitaxially on the surface of semiconductor material.« less

  20. Poly(ethylene oxide)-Assisted Macromolecular Self-Assembly of Lignin in ABS Matrix for Sustainable Composite Applications

    SciTech Connect (OSTI)

    Akato, Kokouvi M.; Tran, Chau D.; Chen, Jihua; Naskar, Amit K.

    2015-11-05

    Here we report the compatibilization of biomass-derived lignin polymer in acrylonitrile butadiene styrene (ABS) thermoplastic matrix without loss of mechanical properties via poly(ethylene oxide) (PEO)-mediated macromolecular self-assembly. ABS was blended with lignin in different concentrations, and blends with 10 wt % PEO (relative to lignin) were prepared. The relative tensile strength improved slightly at low lignin content but diminished rapidly as the lignin content was increased. However, the inclusion of PEO as an interfacial adhesion promoter helped avoid deleterious effects. Dynamic mechanical analysis showed that PEO plasticized the hard phase and thus lowered the activation energy (Ea) for its relaxation but caused stiffening of the soft phase and increased its Ea. Microscopy revealed that incorporating lignin in ABS led to the statistical dispersion of discrete lignin domains (300–1000 nm) which, after PEO addition, were reduced to smaller interconnected particles (200–500 nm). The lignin-extended partially renewable ABS resins showed shear-thinning behavior and reduced viscosity compared to neat ABS. The preferred lignin-loaded compositions reinforced with 20 vol % chopped carbon fibers exhibited mechanical performances (77–80 MPa) equivalent to those of reinforced ABS materials reportedly used in 3D printing applications. In conclusion, this approach could lower the cost of ABS while reducing its carbon footprint.

  1. Arc Plasma Synthesis of Nanostructured Materials: Techniques and Innovations

    SciTech Connect (OSTI)

    Das, A. K.; Bhoraskar, S. V.; Kakati, M.; Karmakar, Soumen

    2008-10-23

    Arc plasma aided synthesis of nanostructured materials has the potential of producing complex nano phase structures in bulk quantities. Successful implementation of this potential capability to industrial scale nano generation needs establishment of a plasma parameter control regime in terms of plasma gas, flow pattern, pressure, local temperature and the plasma fields to obtain the desired nano phase structures. However, there is a need to design innovative in situ experiments for generation of an extensive database and subsequently to correlate plasma parameters to the size, shape and phase of the generated nanostructures. The present paper reviews the various approaches utilized in the field of arc plasma nanosynthesis in general and in the authors' laboratories in particular. Simple plasma diagnostics and monitoring schemes have been used in conjunction with nano materials characterization tools to explore the possibility of controlling the size, shape, yield and phase composition of the arc generated nanostructures through plasma control. Case studies related to synthesis of AlN, Al2O3, TiO2, ZrO2, ZnO), magnetic (e.g. {gamma}-Fe2O3, Fe3O4) and single elemental materials (e.g. carbon nanotubes) are presented.

  2. Self-Assembled Silica Nano-Composite Polymer Electrolytes: Synthesis, Rheology & Electrochemistry

    SciTech Connect (OSTI)

    Khan, Saad A.: Fedkiw Peter S.; Baker, Gregory L.

    2007-01-24

    The ultimate objectives of this research are to understand the principles underpinning nano-composite polymer electrolytes (CPEs) and facilitate development of novel CPEs that are low-cost, have high conductivities, large Li+ transference numbers, improved electrolyte-electrode interfacial stability, yield long cycle life, exhibit mechanical stability and are easily processable. Our approach is to use nanoparticulate silica fillers to formulate novel composite electrolytes consisting of surface-modified fumed silica nano-particles in polyethylene oxides (PEO) in the presence of lithium salts. We intend to design single-ion conducting silica nanoparticles which provide CPEs with high Li+ transference numbers. We also will develop low-Mw (molecular weight), high-Mw and crosslinked PEO electrolytes with tunable properties in terms of conductivity, transference number, interfacial stability, processability and mechanical strength

  3. Pressure-reaction synthesis of titanium composite materials

    DOE Patents [OSTI]

    Oden, Laurance L.; Ochs, Thomas L.; Turner, Paul C.

    1993-01-01

    A pressure-reaction synthesis process for producing increased stiffness and improved strength-to-weight ratio titanium metal matrix composite materials comprising exothermically reacting a titanium powder or titanium powder alloys with non-metal powders or gas selected from the group consisting of C, B, N, BN, B.sub.4 C, SiC and Si.sub.3 N.sub.4 at temperatures from about 900.degree. to about 1300.degree. C., for about 5 to about 30 minutes in a forming die under pressures of from about 1000 to 5000 psi.

  4. Interfacial Properties and Design of Functional Energy Materials

    SciTech Connect (OSTI)

    Sumpter, Bobby G [ORNL; Liang, Liangbo [ORNL; Nicolai, Adrien [Rensselaer Polytechnic Institute (RPI); Meunier, V. [Rensselaer Polytechnic Institute (RPI)

    2014-01-01

    The vital importance of energy to society continues to demand a relentless pursuit of energy responsive materials that can bridge fundamental chemical structures at the molecular level and achieve improved functionality, such as efficient energy conversion/storage/transmission, over multiple length scales. This demand can potentially be realized by harnessing the power of self-assembly a spontaneous process where molecules or much larger entities form ordered aggregates as a consequence of predominately non-covalent (weak) interactions. Self-assembly is the key to bottom-up design of molecular devices, because the nearly atomic-level control is very difficult to realize in a top-down, e.g., lithographic approach. However, while function (e.g., charge mobility) in simple systems such as single crystals can often be predicted, predicting the function of the great variety of self-assembled molecular architectures is complicated by the lack of understanding and control over nanoscale interactions, mesoscale architectures, and macroscale (long-range) order. To establish a foundation toward delivering practical solutions, it is critical to develop an understanding of the chemical and physical mechanisms responsible for the self-assembly of molecular and hybrid materials on various substrates. Typically molecular self-assembly involves poorly understood non-covalent intermolecular and substrate-molecule interactions compounded by local and/or collective influences from the substrate atomic lattice (symmetry and/or topological features) and electronic structure. Thus, progress towards unraveling the underlying physicochemical processes that control the structure and macroscopic physical, mechanical, electrical, and transport properties of materials increasingly requires tight integration of theory, modeling and simulation with precision synthesis, advanced experimental characterization, and device measurements. In this mode, theory and simulation can greatly accelerate the

  5. Self-assembly of tin wires via phase transformation of heteroepitaxial germanium-tin on germanium substrate

    SciTech Connect (OSTI)

    Wang, Wei; Li, Lingzi; Yeo, Yee-Chia; Tok, Eng Soon

    2015-06-14

    This work demonstrates and describes for the first time an unusual strain-relaxation mechanism by the formation and self-assembly of well-ordered tin wires during the thermal annealing of epitaxial Ge{sub 0.83}Sn{sub 0.17}-on-Ge(001) substrate. Fully strained germanium-tin alloys (Ge{sub 0.83}Sn{sub 0.17}) were epitaxially grown on Ge(001) substrate by molecular beam epitaxy. The morphological and compositional evolution of Ge{sub 0.83}Sn{sub 0.17} during thermal annealing is studied by atomic force microscopy, X-ray diffraction, transmission electron microscopy. Under certain annealing conditions, the Ge{sub 0.83}Sn{sub 0.17} layer decomposes into two stable phases, and well-defined Sn wires that are preferentially oriented along two orthogonal ?100? azimuths are formed. The formation of the Sn wires is related to the annealing temperature and the Ge{sub 0.83}Sn{sub 0.17} thickness, and can be explained by the nucleation of a grain with Sn islands on the outer front, followed by grain boundary migration. The Sn wire formation process is found to be thermally activated, and an activation enthalpy (E{sub c}) of 0.41?eV is extracted. This thermally activated phase transformation, i.e., 2D epitaxial layer to 3D wires, occurs via a mechanism akin to cellular precipitation. This synthesis route of Sn wires opens new possibilities for creation of nanoscale patterns at high-throughput without the need for lithography.

  6. Chemical Functionalization, Self-Assembly, and Applications of Nanomaterials and Nanocomposites

    SciTech Connect (OSTI)

    Jiao, Tifeng; Yan, Xingbin; Balan, Lavinia; Stepanov, Andrey; Chen, Xinqing; Hu, Michael Z.

    2014-01-01

    This special issue addresses the research studies on chemical functionalization, self-assembly, and applications of nanomaterials and nanocomposites. It contains twentyfour articles including two reviews and twenty-two research articles. It is used to create new functional nanomaterials and nanocomposites with a variety of sizes and morphologies such as Zn/Al layered double hydroxide, tin oxide nanowires, FeOOH-modified anion resin, Au nanoclusters silica composite nanospheres, Ti-doped ZnO sol-composite films, TiO2/ZnO composite, graphene oxide nanocomposites, LiFePO4/C nanocomposites, and chitosan nanoparticles. These nanomaterials and nanocomposites have widespread applications in tissue engineering, antitumor, sensors, photoluminescence, electrochemical, and catalytic properties. In addition, this themed issue includes some research articles about self-assembly systems covering organogels and Langmuir films. Furthermore, B. Blasiak et al. performed a literature survey on the recent advances in production, functionalization, toxicity reduction, and application of nanoparticles in cancer diagnosis, treatment, and treatment monitoring. P. Colson et al. performed a literature survey on the recent advances in nanosphere lithography due to its compatibility with wafer-scale processes as well as its potential to manufacture a wide variety of homogeneous one-, two-, or three-dimensional nanostructures.

  7. Self-assembled monolayer mechanism for corrosion inhibition of iron by imidazolines

    SciTech Connect (OSTI)

    Ramachandran, S.; Tsai, B.L.; Blanco, M.; Goddard, W.A. III; Chen, H.; Tang, Y.

    1996-12-25

    Some of the most effective corrosion inhibitors for oil field pipeline applications are the oleic imidazoline (OI) class of molecules. However, the mechanism by which the OIs inhibit corrosion is not known. We report atomistic simulations (quantum mechanics and molecular dynamics) designed to elucidate this mechanism. These studies lead to the self-assembled monolayer (SAM) model for corrosion inhibition, which explains the differences in corrosion inhibition efficiency for various OI molecules. The SAM model of OI inhibitors involves the following critical elements: (i) strong bonding of the head group to Lewis acid sites on the iron oxide surface, (ii) self-assembly of the inhibitors on these surfaces to obtain a pattern controlled by the shape of the head group, (iii) self-organization of the tails to form a coherent hydrophobic film that serves as a barrier for migration of water, oxygen, and electrons to the metal surface, and (iv) optimal oil/water partitioning of the inhibitor molecules so that a monolayer can be formed on the surface with only ppm concentration in solution. 25 refs., 13 figs., 3 tabs.

  8. Strain-relief by single dislocation loops in calcite crystals grown on self-assembled monolayers

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

    Ihli, Johannes; Clark, Jesse N.; Côté, Alexander S.; Kim, Yi-Yeoun; Schenk, Anna S.; Kulak, Alexander N.; Comyn, Timothy P.; Chammas, Oliver; Harder, Ross J.; Duffy, Dorothy M.; et al

    2016-06-15

    Most of our knowledge of dislocation-mediated stress relaxation during epitaxial crystal growth comes from the study of inorganic heterostructures. In this study, we use Bragg coherent diffraction imaging to investigate a contrasting system, the epitaxial growth of calcite (CaCO3) crystals on organic self-assembled monolayers, where these are widely used as a model for biomineralization processes. The calcite crystals are imaged to simultaneously visualize the crystal morphology and internal strain fields. Our data reveal that each crystal possesses a single dislocation loop that occupies a common position in every crystal. The loops exhibit entirely different geometries to misfit dislocations generated inmore » conventional epitaxial thin films and are suggested to form in response to the stress field, arising from interfacial defects and the nanoscale roughness of the substrate. In conclusion, this work provides unique insight into how self-assembled monolayers control the growth of inorganic crystals and demonstrates important differences as compared with inorganic substrates.« less

  9. Cooperative, Multicentered CH/ Interaction-Controlled Supramolecular Self-Assembly Processes

    SciTech Connect (OSTI)

    Li, Qing; Han, Chengbo; Horton, Scott R; Fuentes-Cabrera, Miguel A; Sumpter, Bobby G; Lu, Wenchang; Bernholc, J.; Maksymovych, Petro; Pan, Minghu

    2012-01-01

    Supramolecular self-assembly on well-defined surfaces provides access to a multitude of nanoscale architectures, including clusters of distinct symmetry and size. The driving forces underlying supramolecular structures generally involve both graphoepitaxy and weak directional nonconvalent interactions. Here we show that functionalizing a benzene molecule with an ethyne group introduces attractive interactions in a 2D geometry, which would otherwise be dominated by intermolecular repulsion. Furthermore, the attractive interactions enable supramolecular self-assembly, wherein a subtle balance between very weak CH/{pi} bonding and molecule-surface interactions produces a well-defined 'magic' dimension and chirality of supramolecular clusters. The nature of the process is corroborated by extensive scanning tunneling microscopy/spectroscopy (STM/S) measurements and ab initio calculations, which emphasize the cooperative, multicenter characters of the CH/{pi} interaction. This work points out new possibilities for chemical functionalization of {pi}-conjugated hydrocarbon molecules that may allow for the rational design of supramolecular clusters with a desired shape and size.

  10. Molecular Behavior of DNA Origami in Higher-Order Self-Assembly

    SciTech Connect (OSTI)

    Li, Zhe; Liu, Minghui; Lei, Wang; Nangreave, Jeanette; Yan, Hao; Liu, Yan

    2010-09-08

    DNA-based self-assembly is a unique method for achieving higher-order molecular architectures made possible by the fact that DNA is a programmable information-coding polymer. In the past decade, two main types of DNA nanostructures have been developed: branch-shaped DNA tiles with small dimensions (commonly up to ~20 nm) and DNA origami tiles with larger dimensions (up to ~100 nm). Here we aimed to determine the important factors involved in the assembly of DNA origami superstructures. We constructed a new series of rectangular-shaped DNA origami tiles in which parallel DNA helices are arranged in a zigzag pattern when viewed along the DNA helical axis, a design conceived in order to relax an intrinsic global twist found in the original planar, rectangular origami tiles. Self-associating zigzag tiles were found to form linear arrays in both diagonal directions, while planar tiles showed significant growth in only one direction. Although the series of zigzag tiles were designed to promote two-dimensional array formation, one-dimensional linear arrays and tubular structures were observed instead. We discovered that the dimensional aspect ratio of the origami unit tiles and intertile connection design play important roles in determining the final products, as revealed by atomic force microscopy imaging. This study provides insight into the formation of higher-order structures from self-assembling DNA origami tiles, revealing their unique behavior in comparison with conventional DNA tiles having smaller dimensions.

  11. Shock-induced synthesis of high temperature superconducting materials

    DOE Patents [OSTI]

    Ginley, D.S.; Graham, R.A.; Morosin, B.; Venturini, E.L.

    1987-06-18

    It has now been determined that the unique features of the high pressure shock method, especially the shock-induced chemical synthesis technique, are fully applicable to high temperature superconducting materials. Extraordinarily high yields are achievable in accordance with this invention, e.g., generally in the range from about 20% to about 99%, often in the range from about 50% to about 90%, lower and higher yields, of course, also being possible. The method of this invention involves the application of a controlled high pressure shock compression pulse which can be produced in any conventional manner, e.g., by detonation of a high explosive material, the impact of a high speed projectile or the effect of intense pulsed radiation sources such as lasers or electron beams. Examples and a discussion are presented.

  12. Matching field effects at tesla-level magnetic fields in critical current density in high-Tc superconductors containing self-assembled columnar defects

    SciTech Connect (OSTI)

    Sinclair, J.; Zuev, Yuri L; Cantoni, Claudia; Wee, Sung Hun; Varanasi, C. V.; Thompson, James R; Christen, David K

    2012-01-01

    We have investigated the superconductive transport properties of YBa2Cu3O7 films containing self-assembled columnar arrays of second phase SrZrO3 or BaSnO3 precipitates. A matching condition between columnar pinning sites (aligned at or near the c axis) and external magnetic flux, tilted with respect to them, is identified in the critical current JC.H/ data. The results for the material containing SrZrO3-based pins are analyzed within a simple intuitive model. At matching, the critical current is enhanced above the model prediction. In complementary contact-free investigations of BaSnO3-doped material, matching effects are observed over a wide range of temperatures in the field dependence of JC.H/. The deduced matching fields agree reasonably well with the densities of columnar pins directly observed by scanning electron microscopy.

  13. Nano-Structured Mesoporous Silica Wires with Intra-Wire Lamellae via Evaporation-Induced Self-Assembly in Space-Confined Channels

    SciTech Connect (OSTI)

    Hu, Michael Z.; Shi, Donglu; Blom, Douglas Allen

    2014-04-06

    Evaporation-induced self-assembly (EISA) of silica sol-gel ethanol-water solution mixtures with block-copolymer were studied inside uniform micro/nano channels. Nano-structured mesoporous silica wires, with various intra-wire self-assembly structures including lamellae, were prepared via EISA process but in space-confined channels with the diameter ranging from 50 nm to 200 nm. Membranes made of anodized aluminum oxide (AAO) and track-etched polycarbonate (EPC) were utilized as the arrays of space-confined channels (i.e., 50, 100, and 200-nm EPC and 200-nm AAO) for infiltration and drying of mixture solutions; these substrate membranes were submerged in mixture solutions consisting of a silica precursor, a structure-directing agent, ethanol, and water. After the substrate channels were filled with the solution under vacuum impregnation, the membrane was removed from the solution and dried in air. The silica precursor used was tetra-ethyl othosilicate (TEOS), and the structure-directing agent employed was triblock copolymer Pluronic-123 (P123). It was found that the formation of the mesoporous nanostructures in silica wires within uniform channels were significantly affected by the synthesis conditions including (1) pre-assemble TEOS aging time, (2) the evaporation rate during the vacuum impregnation, and (3) the air-dry temperature. The obtained intra-wire structures, including 2D-hexagonal rods and lamellae, were studied by scanning transmission electron microscopy (STEM). A steric hindrance effect seems to explain well the observed polymer-silica mesophase formation tailored by TEOS aging time. The evaporation effect, air-drying effect, and AAO-vs-EPC substrate effect on the mesoporous structure of the formed silica wires were also presented and discussed.

  14. Nanostructured Materials for Improved Photovoltaics

    SciTech Connect (OSTI)

    Morgan, Sarah E.; Cannon, Gordon C.; Heinhorst, Sabine; Rawlins, James W.

    2004-07-18

    This research addresses the fundamental issues of cell morphology and phase dimensions that determine conversion efficiency in polymeric organic photovoltaic devices. The approach will help explain the relationships between morphological control, domain size, and power conversion efficiency in OPV devices, with the goal of providing direction for development of OPV systems with greater efficiency. The program addresses the DOE Office of Energy Efficiency and Renewable Energy goals of providing economically sustainable clean energy technologies to reduce dependence on foreign oil. This research focused on synthesis, fabrication and analysis of both active and protective layers for improved organic and inorganic hybrid PV (PhotoVoltaic) materials. A systematic study of phase size, shape, and distance was conducted to determine the effects of morphology in each process. Four classes of nanostructured materials were studied: 1) functional block copolymers (AB, acceptor-donor blocks) that self-assemble into matched domain sizes 2) synthetic core-shell particles with separate acceptor and donor layers 3) bacterial micro-compartment (BMC) proteins as self-assembling shells for core-shell nanoparticle constructs and 4) polyhedral oligomeric silsesquioxane (POSS) nanostructured chemicals for enhanced efficiency and durability.

  15. Well-defined PI-b-PAA/PS-b-PI-b-PAA Block Copolymers: Synthesis...

    Office of Scientific and Technical Information (OSTI)

    Media Citation Details In-Document Search Title: Well-defined PI-b-PAAPS-b-PI-b-PAA Block Copolymers: Synthesis and Their Self-Assembled Hierarchical Structures in Aqueous Media ...

  16. ELEMENTARY APPROACH TO SELF-ASSEMBLY AND ELASTIC PROPERTIES OF RANDOM COPOLYMERS

    SciTech Connect (OSTI)

    S. M. CHITANVIS

    2000-10-01

    The authors have mapped the physics of a system of random copolymers onto a time-dependent density functional-type field theory using techniques of functional integration. Time in the theory is merely a label for the location of a given monomer along the extent of a flexible chain. We derive heuristically within this approach a non-local constraint which prevents segments on chains in the system from straying too far from each other, and leads to self-assembly. The structure factor is then computed in a straightforward fashion. The long wave-length limit of the structure factor is used to obtain the elastic modulus of the network. It is shown that there is a surprising competition between the degree of micro-phase separation and the elastic moduli of the system.

  17. Pseudorotational epitaxy of self-assembled octadecyltrichlorosilane monolayers on sapphire (0001)

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

    Steinrück, H. -G.; Magerl, A.; Deutsch, M.; Ocko, B. M.

    2014-10-06

    The structure of octadecyltrichlorosilane self-assembled monolayers (SAMs) on sapphire (0001) was studied by Å-resolution surface-specific x-ray scattering methods. The monolayer was found to consist of three sublayers where the outermost layer corresponds to vertically oriented, closely packed alkyl tails. Laterally, the monolayer is hexagonally packed and exhibits pseudorotational epitaxy to the sapphire, manifested by a broad scattering peak at zero relative azimuthal rotation, with long powderlike tails. The lattice mismatch of ~1% – 3% to the sapphire’s and the different length scale introduced by the lateral Si-O-Si bonding prohibit positional epitaxy. However, the substrate induces an intriguing increase in themore » crystalline coherence length of the SAM’s powderlike crystallites when rotationally aligned with the sapphire’s lattice. As a result, the increase correlates well with the rotational dependence of the separation of corresponding substrate-monolayer lattice sites.« less

  18. Communication: Theoretical prediction of free-energy landscapes for complex self-assembly

    SciTech Connect (OSTI)

    Jacobs, William M.; Reinhardt, Aleks; Frenkel, Daan

    2015-01-14

    We present a technique for calculating free-energy profiles for the nucleation of multicomponent structures that contain as many species as building blocks. We find that a key factor is the topology of the graph describing the connectivity of the target assembly. By considering the designed interactions separately from weaker, incidental interactions, our approach yields predictions for the equilibrium yield and nucleation barriers. These predictions are in good agreement with corresponding Monte Carlo simulations. We show that a few fundamental properties of the connectivity graph determine the most prominent features of the assembly thermodynamics. Surprisingly, we find that polydispersity in the strengths of the designed interactions stabilizes intermediate structures and can be used to sculpt the free-energy landscape for self-assembly. Finally, we demonstrate that weak incidental interactions can preclude assembly at equilibrium due to the combinatorial possibilities for incorrect association.

  19. Pseudo-rotational epitaxy of self-assembled octadecyltrichlorosilane monolayers on sapphire (0001)

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

    Steinruck, H. -G.; Ocko, B. M.; Magerl, A.; Deutsch, M.

    2014-10-06

    The structure of octadecyltrichlorosilane self-assembled monolayers (SAMs) on sapphire (0001) was studied by -resolution surface-specific x-ray scattering methods. The monolayer was found to consist of three sublayers where the outermost layer corresponds to vertically oriented, closely packed alkyl tails. Laterally, the monolayer is hexagonally packed and exhibits pseudorotational epitaxy to the sapphire, manifested by a broad scattering peak at zero relative azimuthal rotation, with long powderlike tails. The lattice mismatch of ~1% 3% to the sapphires and the different length scale introduced by the lateral Si-O-Si bonding prohibit positional epitaxy. However, the substrate induces an intriguing increase in themorecrystalline coherence length of the SAMs powderlike crystallites when rotationally aligned with the sapphires lattice. The increase correlates well with the rotational dependence of the separation of corresponding substrate-monolayer lattice sites.less

  20. Effects of self-assembled monolayer and PFPE lubricant on wear characteristics of flat silicon tips.

    SciTech Connect (OSTI)

    Kim, H. J.; Jang, C. E.; Kim, D. E.; Kim, Y. K.; Choa, S. H.; Hong, S.; Materials Science Division; Yonsei Univ.; Samsung Adv. Inst. Science and Technology; Seoul National Univ. of Technology

    2009-01-01

    The effects of self-assembled monolayer (SAM) and perfluoropolyether (PFPE) lubricant on the wear characteristics of flat silicon tips were investigated. The wear test consisted of sliding the silicon tips fabricated on a flat silicon specimen against SAM and PFPE (Z-tetraol) coated silicon (100) wafer. The tips were slid at a low speed for about 15 km under an applied load of 39.2 {micro}N. The wear volume of the tip was obtained by measuring the tip profile using an Atomic Force Microscope (AFM). It was found that the coatings were effective in reducing the wear of the tips by an order of magnitude from 10{sup -6} to 10{sup -7}.

  1. Self-assembled asymmetric membrane containing micron-size germanium for high capacity lithium ion batteries

    SciTech Connect (OSTI)

    Byrd, Ian; Chen, Hao; Webber, Theron; Li, Jianlin; Wu, Ji

    2015-10-23

    We report the formation of novel asymmetric membrane electrode containing micron-size (~5 μm) germanium powders through a self-assembly phase inversion method for high capacity lithium ion battery anode. 850 mA h g-1 capacity (70%) can be retained at a current density of 600 mA g-1 after 100 cycles with excellent rate performance. Such a high retention rate has rarely been seen for pristine micron-size germanium anodes. Moreover, scanning electron microscope studies reveal that germanium powders are uniformly embedded in a networking porous structure consisting of both nanopores and macropores. It is believed that such a unique porous structure can efficiently accommodate the ~260% volume change during germanium alloying and de-alloying process, resulting in an enhanced cycling performance. Finally, these porous membrane electrodes can be manufactured in large scale using a roll-to-roll processing method.

  2. Self-assembled asymmetric membrane containing micron-size germanium for high capacity lithium ion batteries

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

    Byrd, Ian; Chen, Hao; Webber, Theron; Li, Jianlin; Wu, Ji

    2015-10-23

    We report the formation of novel asymmetric membrane electrode containing micron-size (~5 μm) germanium powders through a self-assembly phase inversion method for high capacity lithium ion battery anode. 850 mA h g-1 capacity (70%) can be retained at a current density of 600 mA g-1 after 100 cycles with excellent rate performance. Such a high retention rate has rarely been seen for pristine micron-size germanium anodes. Moreover, scanning electron microscope studies reveal that germanium powders are uniformly embedded in a networking porous structure consisting of both nanopores and macropores. It is believed that such a unique porous structure can efficientlymore » accommodate the ~260% volume change during germanium alloying and de-alloying process, resulting in an enhanced cycling performance. Finally, these porous membrane electrodes can be manufactured in large scale using a roll-to-roll processing method.« less

  3. Final LDRD report : infrared detection and power generation using self-assembled quantum dots.

    SciTech Connect (OSTI)

    Cederberg, Jeffrey George; Ellis, Robert; Shaner, Eric Arthur

    2008-02-01

    Alternative solutions are desired for mid-wavelength and long-wavelength infrared radiation detection and imaging arrays. We have investigated quantum dot infrared photodetectors (QDIPs) as a possible solution for long-wavelength infrared (8 to 12 {mu}m) radiation sensing. This document provides a summary for work done under the LDRD 'Infrared Detection and Power Generation Using Self-Assembled Quantum Dots'. Under this LDRD, we have developed QDIP sensors and made efforts to improve these devices. While the sensors fabricated show good responsivity at 80 K, their detectivity is limited by high noise current. Following efforts concentrated on how to reduce or eliminate this problem, but with no clear path was identified to the desired performance improvements.

  4. Infrared spectroscopy of large scale single layer graphene on self assembled organic monolayer

    SciTech Connect (OSTI)

    Woo Kim, Nak; Youn Kim, Joo; Lee, Chul; Choi, E. J.; Jin Kim, Sang; Hee Hong, Byung

    2014-01-27

    We study the effect of self-assembled monolayer (SAM) organic molecule substrate on large scale single layer graphene using infrared transmission measurement on Graphene/SAM/SiO{sub 2}/Si composite samples. From the Drude weight of the chemically inert CH{sub 3}-SAM, the electron-donating NH{sub 2}-SAM, and the SAM-less graphene, we determine the carrier density doped into graphene by the three sources—the SiO{sub 2} substrate, the gas-adsorption, and the functional group of the SAM's—separately. The SAM-treatment leads to the low carrier density N ∼ 4 × 10{sup 11} cm{sup −2} by blocking the dominant SiO{sub 2}- driven doping. The carrier scattering increases by the SAM-treatment rather than decreases. However, the transport mobility is nevertheless improved due to the reduced carrier doping.

  5. Pseudorotational epitaxy of self-assembled octadecyltrichlorosilane monolayers on sapphire (0001)

    SciTech Connect (OSTI)

    Steinrück, H. -G.; Magerl, A.; Deutsch, M.; Ocko, B. M.

    2014-10-06

    The structure of octadecyltrichlorosilane self-assembled monolayers (SAMs) on sapphire (0001) was studied by Å-resolution surface-specific x-ray scattering methods. The monolayer was found to consist of three sublayers where the outermost layer corresponds to vertically oriented, closely packed alkyl tails. Laterally, the monolayer is hexagonally packed and exhibits pseudorotational epitaxy to the sapphire, manifested by a broad scattering peak at zero relative azimuthal rotation, with long powderlike tails. The lattice mismatch of ~1% – 3% to the sapphire’s and the different length scale introduced by the lateral Si-O-Si bonding prohibit positional epitaxy. However, the substrate induces an intriguing increase in the crystalline coherence length of the SAM’s powderlike crystallites when rotationally aligned with the sapphire’s lattice. As a result, the increase correlates well with the rotational dependence of the separation of corresponding substrate-monolayer lattice sites.

  6. Material synthesis and hydrogen storage of palladium-rhodium alloy.

    SciTech Connect (OSTI)

    Lavernia, Enrique J.; Yang, Nancy Y. C.; Ong, Markus D.

    2011-08-01

    Pd and Pd alloys are candidate material systems for Tr or H storage. We have actively engaged in material synthesis and studied the material science of hydrogen storage for Pd-Rh alloys. In collaboration with UC Davis, we successfully developed/optimized a supersonic gas atomization system, including its processing parameters, for Pd-Rh-based alloy powders. This optimized system and processing enable us to produce {le} 50-{mu}m powders with suitable metallurgical properties for H-storage R&D. In addition, we studied hydrogen absorption-desorption pressure-composition-temperature (PCT) behavior using these gas-atomized Pd-Rh alloy powders. The study shows that the pressure-composition-temperature (PCT) behavior of Pd-Rh alloys is strongly influenced by its metallurgy. The plateau pressure, slope, and H/metal capacity are highly dependent on alloy composition and its chemical distribution. For the gas-atomized Pd-10 wt% Rh, the absorption plateau pressure is relatively high and consistent. However, the absorption-desorption PCT exhibits a significant hysteresis loop that is not seen from the 30-nm nanopowders produced by chemical precipitation. In addition, we observed that the presence of hydrogen introduces strong lattice strain, plastic deformation, and dislocation networking that lead to material hardening, lattice distortions, and volume expansion. The above observations suggest that the H-induced dislocation networking is responsible for the hysteresis loop seen in the current atomized Pd-10 wt% Rh powders. This conclusion is consistent with the hypothesis suggested by Flanagan and others (Ref 1) that plastic deformation or dislocations control the hysteresis loop.

  7. High-Resolution Structure of a Self-Assembly-Competent Form of a Hydrophobic Peptide Captured in a Soluble [beta]-Sheet Scaffold

    SciTech Connect (OSTI)

    Makabe, Koki; Biancalana, Matthew; Yan, Shude; Tereshko, Valentina; Gawlak, Grzegorz; Miller-Auer, Hlne; Meredith, Stephen C.; Koide, Shohei

    2010-02-08

    {beta}-Rich self-assembly is a major structural class of polypeptides, but still little is known about its atomic structures and biophysical properties. Major impediments for structural and biophysical studies of peptide self-assemblies include their insolubility and heterogeneous composition. We have developed a model system, termed peptide self-assembly mimic (PSAM), based on the single-layer {beta}-sheet of Borrelia outer surface protein A. PSAM allows for the capture of a defined number of self-assembly-like peptide repeats within a water-soluble protein, making structural and energetic studies possible. In this work, we extend our PSAM approach to a highly hydrophobic peptide sequence. We show that a penta-Ile peptide (Ile{sub 5}), which is insoluble and forms {beta}-rich self-assemblies in aqueous solution, can be captured within the PSAM scaffold in a form capable of self-assembly. The 1.1-{angstrom} crystal structure revealed that the Ile{sub 5} stretch forms a highly regular {beta}-strand within this flat {beta}-sheet. Self-assembly models built with multiple copies of the crystal structure of the Ile5 peptide segment showed no steric conflict, indicating that this conformation represents an assembly-competent form. The PSAM retained high conformational stability, suggesting that the flat {beta}-strand of the Ile{sub 5} stretch primed for self-assembly is a low-energy conformation of the Ile{sub 5} stretch and rationalizing its high propensity for self-assembly. The ability of the PSAM to 'solubilize' an otherwise insoluble peptide stretch suggests the potential of the PSAM approach to the characterization of self-assembling peptides.

  8. Biomimetic Nanocomposites of Calcium Phosphate and Self-Assembling Triblock and Pentablock Copolymers

    SciTech Connect (OSTI)

    Drew Lenzen Enlow

    2006-08-09

    In an effort to mimic the growth of natural bone, self-assembling, micelle and gel-forming copolymers were used as a template for calcium phosphate precipitation. Because of the cationic characteristics imparted by PDEAEM end group additions to commercially available Pluronic{reg_sign} Fl27, a direct ionic attraction mechanism was utilized and a polymer-brushite nanocomposite spheres were produced. Brushite coated spherical micelles with diameters of {approx}40 nm, and agglomerates of these particles (on the order of 0.5 {mu}m) were obtained. Thickness and durability of the calcium phosphate coating, and the extent of agglomeration were studied. The coating has been shown to be robust enough to retain its integrity even below polymer critical micelle concentration and/or temperature. Calcium phosphate-polymer gel nanocomposites were also prepared. Gel samples appeared as a single phase network of agglomerated spherical micelles, and had a final calcium phosphate concentration of up to 15 wt%. Analysis with x-ray diffraction and NMR indicated a disordered brushite phase with the phosphate groups linking inorganic phase to the polymer.

  9. Fluorescence enhancement in large-scale self-assembled gold nanoparticle double arrays

    SciTech Connect (OSTI)

    Chekini, M.; Bierwagen, J.; Cunningham, A.; Bürgi, T.; Filter, R.; Rockstuhl, C.

    2015-12-21

    Localized surface plasmon resonances excited in metallic nanoparticles confine and enhance electromagnetic fields at the nanoscale. This is particularly pronounced in dimers made from two closely spaced nanoparticles. When quantum emitters, such as dyes, are placed in the gap of those dimers, their absorption and emission characteristics can be modified. Both processes have to be considered when aiming to enhance the fluorescence from the quantum emitters. This is particularly challenging for dimers, since the electromagnetic properties and the enhanced fluorescence sensitively depend on the distance between the nanoparticles. Here, we use a layer-by-layer method to precisely control the distances in such systems. We consider a dye layer deposited on top of an array of gold nanoparticles or integrated into a central position of a double array of gold nanoparticles. We study the effect of the spatial arrangement and the average distance on the plasmon-enhanced fluorescence. We found a maximum of a 99-fold increase in the fluorescence intensity of the dye layer sandwiched between two gold nanoparticle arrays. The interaction of the dye layer with the plasmonic system also causes a spectral shift in the emission wavelengths and a shortening of the fluorescence life times. Our work paves the way for large-scale, high throughput, and low-cost self-assembled functionalized plasmonic systems that can be used as efficient light sources.

  10. Charge Retention by Peptide Ions Soft-Landed onto Self-Assembled Monolayer Surfaces

    SciTech Connect (OSTI)

    Laskin, Julia; Wang, Peng; Hadjar, Omar; Futrell, Jean H.; Alvarez, Jormarie; Cooks, Robert G.

    2007-08-01

    Soft-landing of singly and doubly protonated peptide ions onto three self-assembled monolayer surfaces (SAMs) was performed using a novel ion deposition instrument constructed in our laboratory and a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially designed for studying collisions of large ions with surfaces.. Modified surfaces were analyzed using in situ 2 keV Cs+ secondary ion mass spectrometry or ex situ 15 keV Ga+ time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results demonstrate that a fraction of multiply protonated peptide ions retain more than one proton following soft-landing on the FSAM surface. [M+2H]2+ ions observed in FT-ICR SIMS spectra are produced by desorption of multiply charged ions from the surface, while re-ionization of singly protonated ions or neutral peptides is a source of [M+2H]2+ ions in Tof-SIMS spectra. Differences in neutralization efficiency of soft-landed ions following exposure of surfaces to laboratory air has a measurable effect on the results of ex situ ToF-SIMS analysis of soft-landed ions on SAM surfaces.