Download or read book Growth and Characterization of Iron Pyrite Thin Films and Single Crystals for Applications in Photovoltaics written by Nicholas Eli Berry and published by . This book was released on 2012 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: Iron pyrite (FeS2) is a promising earth abundant semiconductor for applications in thin film photovoltaics. This thesis focuses on the growth and characterization of pyrite thin films and single crystals. Single phase, large grain, and uniform polycrystalline pyrite thin films are fabricated on glass and molybdenum coated glass substrates by atmospheric-pressure chemical vapor deposition using the reaction of iron (III) acetylacetonate and tert-butyl disulfide in argon at 300°C, followed by sulfur annealing at 500-550°C to convert marcasite impurities to pyrite. Large, pure phase, and high quality pyrite single crystals were grown using a Na2S based flux growth technique. Thin films and single crystals were characterized by numerous techniques including X-ray diffraction, Raman spectroscopy and Hall effect measurements. The films exhibit low mobility, high carrier concentration p-type behavior while the single crystals exhibit high mobility, low carrier concentration n-type behavior, consistent with literature. The temperature dependence of the hall coefficient of single crystals shows the first clear transition from n-type behavior at room temperature to p-type behavior at low temperatures in pyrite. In addition, simple polishing of the surface is shown to modify the concentration of holes, demonstrating that p-type carriers can originate from the surface of a high quality pyrite single crystal.
Download or read book Synthesis and Characterization of Pyrite Thin Films and Single Crystals for PV Devices and Fundamental Studies written by Nima Farhi and published by . This book was released on 2016 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: Iron pyrite is an earth-abundant, non-toxic, and inexpensive semiconductor that has the potential to produce large photocurrents in photovoltaic devices. However, the efficiency of pyrite solar cell devices has been limited by its photovoltage (
Download or read book Growth and Characterization of Pyrite Thin Films for Photovoltaic Applications written by Alex Wertheim and published by . This book was released on 2014 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: A series of pyrite thin films were synthesized using a novel sequential evaporationtechnique to study the effects of substrate temperature on deposition rate and micro-structure ofthe deposited material. Pyrite was deposited in a monolayer-by-monolayer fashion usingsequential evaporation of Fe under high vacuum, followed by sulfidation at high S pressures(typically> 1 mTorr to 1 Torr). Thin films were synthesized using two different growth processes; aone-step process in which a constant growth temperature is maintained throughout growth, and athree-step process in which an initial low temperature seed layer is deposited, followed by a hightemperature layer, and then finished with a low temperature capping layer. Analysis methods toanalyze the properties of the films included Glancing Angle X-Ray Diffraction (GAXRD), Rutherford Back-scattering Spectroscopy (RBS), Transmission Electron Microscopy (TEM), Secondary Ion Mass Spectroscopy (SIMS), 2-point IV measurements, and Hall effectmeasurements. Our results show that crystallinity of the pyrite thin film improves and grain sizeincreases with increasing substrate temperature. The sticking coefficient of Fe was found toincrease with increasing growth temperature, indicating that the Fe incorporation into the growingfilm is a thermally activated process.
Download or read book Solution based Syntheses of Iron Pyrite Thin Films for Photovoltaic and Protein Foot printing Applications written by Mohammed El Makkaoui and published by . This book was released on 2015 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Iron pyrite (cubic FeS2) is a non-toxic, earth abundant semiconductor possessing a set of excellent optical/electronic properties for serving as an absorber layer in PV devices. Additionally, pyrite is a very efficient hydroxyl radical generator via Fenton chemistry and has shown promise in oxidative protein and DNA foot-printing application. The main focus of this thesis is on fabricating phase and elementally pure iron pyrite thin films using a solution-based approach that employs hydrazine as a solvent. A precursor ink is formed at room temperature by mixing elemental iron and sulfur in anhydrous hydrazine and then deposited on Mo-coated glass substrates, via spin coating, to yield amorphous iron sulfide films that are then annealed in H2S (340 o C) and sulfur gas (less than or equal 500 °C) to form uniform, polycrystalline and phase pure pyrite films with densely packed grains. This approach is likely to yield the most elementally pure pyrite thin films made to date, through a very simple and scalable process. The ink has shown to be very sensitive to environmental conditions and has a very short shelf life (~1 day). Additionally, the film microstructure is greatly influenced by the S:Fe concentration ratio that when tuned to 3:1, yielded uniform, robust and optically flat iron sulfide thin films with an optimal thickness (~320 nm) for PV application. The results however were not reproducible, mainly due to failure in applying multiple layers without compromising film morphology. Thinner ( 100 nm) iron sulfide films, on the other hand, are reproducibly produced, but are too thin to be employed in PV devices. Direct annealing in sulfur gas at 475 °C for 4 hours, bypassing the 12 hour H2S annealing step, yielded phase pure pyrite films, with good morphology, at lower processing time and annealing temperatures (
Download or read book Pyrite Thin Films written by Sean Michael Seefeld and published by . This book was released on 2012 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work in this thesis includes a combination of four methods and applications for pyrite thin films produced via solution based processes. Chapter 1 provides a brief introduction into earth abundant materials for photovoltaic applications. The issue of supply and price constraints is explored, and the motivation for pyrite thin films is explained. The fundamental properties of pyrite are provided along with a synopsis of previous pyrite device constructions and results. Chapter 2 discusses the synthesis and characterization of phase-pure, single-crystalline, and clustered FeS2 nanocrystals synthesized in a one-pot "heat-up" synthesis. The NCs were then subjected to ligand removal with hydrazine to form polycrystalline pyrite thin films by sintering these layers of NCs at 450-600° under a sulfur atmosphere. The sintering behavior and precursor chemistry are explored. Chapter 3 discusses the synthesis and characterization of phase-pure, single-crystalline, and well-dispersed colloidal FeS2 nanocrystals (NCs) synthesized in high yield by a simple hot-injection route in octadecylamine. The NCs were then subjected to partial ligand exchange with octadecylxanthate to yield stable pyrite NC inks. Polycrystalline pyrite thin films were fabricated by sintering layers of these NCs at 450-600°C under a sulfur atmosphere. Chapter 4 briefly covers the application of the FeS2 nanocrystals used in lithographically patterned microfluidic devices. Nanocrystals are solution deposited inside lithographically patterned channels on glass substrates. Subsequent ligand exchanges inside these channels allow for use of these patterned nanocrystal channels to develop microfluidic devices for DNA protein interaction footprinting. Chapter 5 reports on solution-deposited, single-phase, large-grain, and uniform polycrystalline iron pyrite (FeS2) thin films fabricated on quartz and molybdenum-coated glass substrates from an iron (III) acetylacetonate molecular ink. The ink, prepared as a viscous solution of Fe(acac)3 and sulfur in pyridine, is spin coated and baked in air utilizing a layer by layer process to produce ~300 nm thick, mixed-phase pyrite/marcasite thin films after annealing in H2S atmosphere. A second annealing step in sulfur vapor at 450-600°C yields phase-pure pyrite films with suitable morphology and mechanical properties for use in solar cells. The resulting pyrite films are characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), secondary ion mass spectrometry (SIMS), optical absorption spectroscopy, and variable-temperature Hall effect measurements.
Download or read book Molecular Ink Processed Iron Pyrite Thin Films for Photovoltaics written by Amanda Sue Weber and published by . This book was released on 2015 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin-film photovoltaics (PV) have the potential to supply our future energy needs, but the dominant commercial thin film technologies rely on rare or toxic elements that may limit their capacity to scale to the terawatt levels of electricity generation needed to impact global energy demand. Iron pyrite (FeS2) is a promising, earth-abundant material that has a suitable band gap of 0.95 eV, a large optical absorption coefficient, and adequate carrier diffusion lengths for use in PV. Unfortunately pyrite solar cells have suffered from low open circuit voltages that hinder overall device performance. Developing high quality, phase pure pyrite thin films may be the key to overcoming these performance drawbacks. A solution-based process using elemental precursors dissolved in hydrazine has been previously developed at IBM for fabricating solar absorbers such as copper zinc tin selenide/sulfide (CZTS) and copper indium gallium selenide/sulfide (CIGS). Devices using these films have achieved 12.6% and 15.2% efficiencies respectively. In this dissertation, a hydrazine-free molecular ink that uses common organic solvents to dissolve elemental iron and sulfur is described for making pyrite thin films. To form pyrite thin films, the molecular ink is deposited onto molybdenum-coated glass and then annealed at temperatures between 350-500°C in both hydrogen sulfide and sulfur vapor atmospheres. Phase purity is confirmed using X-ray diffraction and Raman spectroscopy. Film morphology is examined with scanning electron microscopy. Elemental composition is analyzed using secondary ion mass spectrometry and FT-IR spectroscopy. Optical properties are measured using an integrating sphere attachment on a UV-VIS spectrometer. The electrical properties of the films are characterized by temperature-dependent resistivity and qualitative thermopower to verify the carrier type. The resulting films are measured to be pure phase pyrite that consist of well-connected grains between 50-200 nm in size and are free of pinholes. Optical and electrical properties agree with those commonly cited in literature. Elemental analysis reveals low amounts of oxygen and carbon impurities, compared to other fabrication methods of pyrite used in the same laboratory. The initial results of using these films in p-n heterojunctions will be presented along with on-going strategies being researched to overcome new challenges..
Download or read book A Study on the Synthesis of Iron Pyrite Thin Films for Use as a Photovoltaic Absorber written by Amitabha Sarkar and published by . This book was released on 2014 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although iron pyrite had been identified as a novel photo-voltaic material, it is yet to be harnessed. Iron pyrite forms mechanically unstable films with pinholes. A simple method has been devised to greatly improve the mechanical stability of iron pyrite thin films grown on quartz. This is done by annealing the precursor films prior to sulfurizing in vacuum-sealed quartz tubes. It has also been shown that an equilibrium based process is necessary to synthesize films of good quality. Zinc was successfully incorporated into iron pyrite thin films to increase the bandgap by 0.1 eV. The electronic properties of these films are similar to that found in literature. It has been identified that cracks in the film and voids between the grains are the cause for poor electronic properties. Composition analysis showed a high degree of oxygen contamination in iron precursor films resulting in poor electronic properties of iron pyrite films obtained by sulfuring the precursor films. Thus it may be possible to synthesize high quality films if these issues are addressed.
Download or read book Metal Halide Perovskite Crystals Growth Techniques Properties and Emerging Applications written by Wei Zhang and published by . This book was released on 2019 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, metal halide perovskites have emerged as a rising star among semiconductor materials owing to their low cost, solution processability, and fascinating combination of material properties enabling a broad range of energy applications. Accompanied by the unprecedented success in the photovoltaic community, which has witnessed a certified power conversion efficiency of 23.7%, rapid advancement has also been achieved in the areas of light-emitting diodes, lasers, photodetectors, and solar-to-fuel energy conversion devices. Beyond the dominant format of polycrystalline perovskite thin films for solar cell applications, recent progress in metal halide perovskite crystals, ranging from nanocrystals to macroscopic single-crystals, has spurred a great deal of both scientific and industrial interest. Great research efforts have endeavored to develop new techniques for crystal growth and investigate the physical and chemical properties of the materials and explore their emerging applications. These exciting achievements call for a rationalization of the different forms of perovskite semiconductors beyond the widely used polycrystalline thin films. In the current Special Issue, "Metal Halide Perovskite Crystals: Growth Techniques, Properties and Emerging Applications", we aim to provide a forum for the discussion and presentation of recent advances in the fields of research related to metal halide perovskite crystals.
Download or read book Growth and Characterization of Copper Indium Disulphide Photovoltaic Thin Films Using Single Source Liquid Precursors written by Chitti Kumar Nagendra Lekkala and published by . This book was released on 2006 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth and Characterisation of Copper Indium Disulfide Thin Films for Photovoltaic Applications Using Solid Single Source Precursors written by Ashish Singh Negi and published by . This book was released on 2005 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Composition and Morphology Control of Metal Dichalcogenides Via Chemical Vapor Deposition for Photovoltaic and Nanoelectronic Applications written by Leith L. J. Samad and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The body of work reviewed here encompasses a variety of metal dichalcogenides all synthesized using chemical vapor deposition (CVD) for solar and electronics applications. The first reported phase-pure CVD synthesis of iron pyrite thin films is presented with detailed structural and electrochemical analysis. The phase-pure thin film and improved crystal growth on a metallic backing material represents one of the best options for potential solar applications using iron pyrite. Large tin-sulfur-selenide solid solution plates with tunable bandgaps were also synthesized via CVD as single-crystals with a thin film geometry. Solid solution tin-sulfur-selenide plates were demonstrated to be a new material for solar cells with the first observed solar conversion efficiencies up to 3.1%. Finally, a low temperature molybdenum disulfide vertical heterostructure CVD synthesis with layered controlled growth was achieved with preferential growth enabled by Van der Waals epitaxy. Through recognition of additional reaction parameters, a fully regulated CVD synthesis enabled the controlled growth of 1-6 molybdenum disulfide monolayers for nanoelectronic applications. The improvements in synthesis and materials presented here were all enabled by the control afforded by CVD such that advances in phase purity, growth, and composition control of several metal dichalcogenides were achieved. Further work will be able to take full advantage of these advances for future solar and electronics technologies.
Download or read book Nanomineralogy written by Yiwen Ju and published by MDPI. This book was released on 2020-12-14 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2018, the International Symposium on Nanogeoscience was held in Guiyang, China. Scholars from around the globe gathered to discuss recent progress and development trends in various aspects of nanogeoscience, including nanomineralogy. Nanomineralogy, an important aspect of nanogeoscience, focuses on the composition, structure, and physical and chemical properties of nanoscale minerals and their interrelations with other Earth critical components. To give a sampling of the latest progress in nanomineralogy and related fields, we offer this Special Issue, which describes a full range of recent nanomineralogic achievements relating to everything from nanominerals and geochemistry, mineral nanostructures, and nanomineral deformation, to nanopores in oil and gas reservoirs, nanomineral deposits, and nanomineral material. Today, nanomineralogy faces a new strategic opportunity as well as a revolutionary challenge. We thus present this special nanomineralogy-focused issue of Minerals with the aim of encouraging our colleagues to familiarize themselves with current developments, trends, and directions in nanomineralogy, enabling an understanding of the potential of the field as a whole. We look forward to developing further scientific research and cooperation in nanomineralogy, hoping thereby to attract and guide young scholars to participate in this field.
Download or read book Solar Cell Device Physics written by Stephen J. Fonash and published by Academic Press. This book was released on 2010-06-17 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: There has been an enormous infusion of new ideas in the field of solar cells over the last 15 years; discourse on energy transfer has gotten much richer, and nanostructures and nanomaterials have revolutionized the possibilities for new technological developments. However, solar energy cannot become ubiquitous in the world's power markets unless it can become economically competitive with legacy generation methods such as fossil fuels. The new edition of Dr. Stephen Fonash's definitive text points the way toward greater efficiency and cheaper production by adding coverage of cutting-edge topics in plasmonics, multi-exiton generation processes, nanostructures and nanomaterials such as quantum dots. The book's new structure improves readability by shifting many detailed equations to appendices, and balances the first edition's semiconductor coverage with an emphasis on thin-films. Further, it now demonstrates physical principles with simulations in the well-known AMPS computer code developed by the author. Classic text now updated with new advances in nanomaterials and thin films that point the way to cheaper, more efficient solar energy production Many of the detailed equations from the first edition have been shifted to appendices in order to improve readability Important theoretical points are now accompanied by concrete demonstrations via included simulations created with the well-known AMPS computer code
Download or read book Materials Science and Industrial Applications II written by Zhi Gang Fang and published by Trans Tech Publications Ltd. This book was released on 2020-07-10 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Selected peer-reviewed papers from the 2nd International Conference on Materials Science and Industrial Applications (MSIA 2020) Selected, peer-reviewed papers from the 2nd International Conference on Materials Science and Industrial Applications (MSIA 2020), January 11-12, 2020, Xi’an, China
Download or read book Thin Film Analysis by X Ray Scattering written by Mario Birkholz and published by John Wiley & Sons. This book was released on 2006-05-12 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: With contributions by Paul F. Fewster and Christoph Genzel While X-ray diffraction investigation of powders and polycrystalline matter was at the forefront of materials science in the 1960s and 70s, high-tech applications at the beginning of the 21st century are driven by the materials science of thin films. Very much an interdisciplinary field, chemists, biochemists, materials scientists, physicists and engineers all have a common interest in thin films and their manifold uses and applications. Grain size, porosity, density, preferred orientation and other properties are important to know: whether thin films fulfill their intended function depends crucially on their structure and morphology once a chemical composition has been chosen. Although their backgrounds differ greatly, all the involved specialists a profound understanding of how structural properties may be determined in order to perform their respective tasks in search of new and modern materials, coatings and functions. The author undertakes this in-depth introduction to the field of thin film X-ray characterization in a clear and precise manner.
Download or read book Metals Abstracts Index written by and published by . This book was released on 1980 with total page 1268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solar Energy Conversion and Storage written by Suresh C. Ameta and published by CRC Press. This book was released on 2015-11-05 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solar Energy Conversion and Storage: Photochemical Modes showcases the latest advances in solar cell technology while offering valuable insight into the future of solar energy conversion and storage. Focusing on photochemical methods of converting and/or storing light energy in the form of electrical or chemical energy, the book:Describes various t
