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Articles 1 - 8 of 8
Full-Text Articles in Inorganic Chemistry
The Development Of 6.7% Efficient Copper Zinc Indium Selenide Devices From Copper Zinc Indium Sulfide Nanocrystal Inks, Brian Kemp Graeser
The Development Of 6.7% Efficient Copper Zinc Indium Selenide Devices From Copper Zinc Indium Sulfide Nanocrystal Inks, Brian Kemp Graeser
Open Access Theses
As solar cell absorber materials, alloys of CuIn(S,Se)2 and Zn(S,Se) provide an opportunity to reduce the usage of indium along with the ability to tune the band gap. Here we report successful synthesis of alloyed (CuInS2 )0.5(ZnS)0.5 nanocrystals by a method that solely uses oleylamine as the liquid medium for synthesis. The reactive sintering of a thin film of these nanocrystals via selenization at 500 °C results in a uniform composition alloy (CuIn(S,Se)2 )0.5 (Zn(S,Se)) 0.5 layer with micron size grains. Due to the large amount of zinc in the film, the sintered grains exhibit the zinc blende structure instead …
Nanoparticle Film Assemblies As Platforms For Electrochemical Biosensing – Factors Affecting Amperometric Signal Enhancement Of Hydrogen Peroxide, Adrienne R. Schmidt, Natalie D. T. Nguyen, Michael C. Leopold
Nanoparticle Film Assemblies As Platforms For Electrochemical Biosensing – Factors Affecting Amperometric Signal Enhancement Of Hydrogen Peroxide, Adrienne R. Schmidt, Natalie D. T. Nguyen, Michael C. Leopold
Chemistry Faculty Publications
Factors affecting the enhanced amperometric signal observed at electrodes modified with polyelectrolyte–gold nanoparticle (Au-NP) composite films, which are potential interfaces for first-generation biosensors, were systematically investigated and optimized for hydrogen peroxide (H2O2) detection. Polyelectrolyte multilayer films embedded with citrate-stabilized gold nanoparticles exhibited high sensitivity toward the oxidation of H2O2. From this Au-NP film assembly, the importance of Au-NP ligand protection, film permeability, the density of Au-NPs within the film, and electronic coupling between Au-NPs (interparticle) and between the film and the electrode (interfacial) were evaluated. Using alternative Au-NPs, including those stabilized with thiols, polymers, and bulky ligands, suggests that the …
High Temperature Rare Earth Compounds: Synthesis, Characterization And Applications In Device Fabrication, Joseph R. Brewer
High Temperature Rare Earth Compounds: Synthesis, Characterization And Applications In Device Fabrication, Joseph R. Brewer
Department of Chemistry: Dissertations, Theses, and Student Research
As the area of nanotechnology continues to grow, the development of new nanomaterials with interesting physical and electronic properties and improved characterization techniques are several areas of research that will be remain vital for continued improvement of devices and the understanding in nanoscale phenomenon. In this dissertation, the chemical vapor deposition synthesis of rare earth (RE) compounds is described in detail. In general, the procedure involves the vaporization of a REClx (RE = Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho) in the presence of hydride phase precursors such as decaborane and ammonia at high temperatures and low …
Stable Aqueous Nanoparticle Film Assemblies With Covalent And Charged Polymer Linking Networks, Lesley E. Russell, Anne A. Galyean, Sherilyn M. Notte, Michael C. Leopold
Stable Aqueous Nanoparticle Film Assemblies With Covalent And Charged Polymer Linking Networks, Lesley E. Russell, Anne A. Galyean, Sherilyn M. Notte, Michael C. Leopold
Chemistry Faculty Publications
The construction of highly stable and efficiently assembled multilayer films of purely water soluble gold nanoparticles is reported. Citrate-stabilized nanoparticles (CS-NPs) of average core diameter of 10 nm are used as templates for stabilization-based exchange reactions with thioctic acid to form more robust aqueous NPs that can be assembled into multilayer films. The thioctic acid stabilized nanoparticles (TAS-NPs) are networked via covalent and electrostatic linking systems, employing dithiols and the cationic polymer poly(l-lysine), respectively. Multilayer films of up to 150 nm in thickness are successfully grown at biological pH with no observable degradation of the NPs within the film. The …
Modification Of Semi-Metal Oxide And Metal Oxide Powders By Atomic Layer Deposition Of Thin Films, Mark Q. Snyder
Modification Of Semi-Metal Oxide And Metal Oxide Powders By Atomic Layer Deposition Of Thin Films, Mark Q. Snyder
Electronic Theses and Dissertations
This work describes two methods of modifying, and the subsequent characterizing of, oxide nanopowders. The first method, atomic layer deposition, or ALD, is a series of surface-limited reactions that are repeated to deposit a thin, inorganic film on the surface of the nanopowder. Deposition of a thin film is a useful method to alter the surface properties of a material while retaining its bulk properties. Part of this thesis concerns the understanding of the growth mechanism of thin film titanium nitride (a material known for thermal and chemical stability as well as electronic conductivity) on silica through the ALD process. …
Reactions Of Alcohols And Organophosphonates On Tungsten Trioxide Epitaxial Films, Shuguo Ma
Reactions Of Alcohols And Organophosphonates On Tungsten Trioxide Epitaxial Films, Shuguo Ma
Electronic Theses and Dissertations
The adsorption, diffusion, reactions, and desorption of water, alcohols, ethers, and an organophosphonate were studied using calibrated thermal desorption spectroscopy (CTDS) on thin film WO3(OOl) surfaces grown epitaxially on a single crystal α- Al2O3(li02) (sapphire) substrate. The studies were conducted on oxidized and reduced surfaces, which were characterized by x-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). The desorption spectra for molecular desorption of all of these molecules shifted to lower temperature with increasing coverage, and had overlapping tails on the high temperature side. Monte Carlo simulations show that this typical desorption shape …
Stabilization Of Rutile-Related Thin Film On Tio2 Substrates, Youngnam Cho
Stabilization Of Rutile-Related Thin Film On Tio2 Substrates, Youngnam Cho
Electronic Theses and Dissertations
Conducting metal oxide thin films are of broad interest because they have a wide variety of magnetic and electronic properties. Materials exist that range from superconducting to insulating, are ferromagnetic and are ferroelectric. These properties make thin conducting oxide films attractive for many industrial applications. A class of metal oxides exists that adapt the rutile crystal structure; the structure of the mineral rutile, TiO2. These metal oxides have the general formula MO2 where M is a metal cation of valence +4. Metal oxides crystallizing in the rutile structure also display a wide variety of physical properties. The …
Electron Hopping Conductivity And Vapor Sensing Properties Of Flexible Network Polymer Films Of Metal Nanoparticles, Francis P. Zamborini, Michael C. Leopold, Jocelyn F. Hicks, Pawel J. Kulesza, Marcin A. Malik, Royce W. Murray
Electron Hopping Conductivity And Vapor Sensing Properties Of Flexible Network Polymer Films Of Metal Nanoparticles, Francis P. Zamborini, Michael C. Leopold, Jocelyn F. Hicks, Pawel J. Kulesza, Marcin A. Malik, Royce W. Murray
Chemistry Faculty Publications
Films of monolayer protected Au clusters (MPCs) with mixed alkanethiolate and ω-carboxylate alkanethiolate monolayers, linked together in a network polymer by carboxylate-Cu2+-carboxylate bridges, exhibit electronic conductivities (σEL) that vary with both the numbers of methylene segments in the ligands and the bathing medium (N2, liquid or vapor). A chainlength-dependent swelling/contraction of the film's internal structure is shown to account for changes in σEL. The linker chains appear to have sufficient flexibility to collapse and fold with varied degrees of film swelling or dryness. Conductivity is most influenced (exponentially dependent) by the chainlength of the nonlinker (alkanethiolate) ligands, a result consistent …