Download or read book Synthesis and Characterization of Iron Pyrite Nanocrystals for Photovoltaic Devices written by Scott Curtis Mangham and published by . This book was released on 2013 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: Iron pyrite nanocrystals have been synthesized using a hot-injection method with a variety of amines and characterized with properties necessary for photovoltaic devices. The iron pyrite nanocrystals were characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, optical absorption, micro-Raman, and micro-Photoluminescence. The optical absorbance spectra showed the large absorption in the visible and near infrared spectral range for the nanocrystals as well as to show the band gap. The face-centered cubic crystal structure of the iron pyrite nanocrystals was shown by matching the measured X-ray diffraction pattern to a face-centered cubic iron pyrite reference pattern. Using Bragg's law and Scherrer's formula helps to calculate the grain size and lattice spacing based upon the X-ray diffraction pattern. The scanning electron microscopy produces images that show the particle size of the nanocrystals while the transmission electron microscopy produced images that show the lattice spacing and grain size for the iron pyrite nanocrystals that are compared to the previously mentioned calculated grain size and lattice spacing. The micro-Raman and micro-Photoluminescence are used to compare the synthesized iron pyrite nanocrystals to natural-bulk iron pyrite. The micro-Photoluminescence is also used to calculate a band gap and compare this band gap to the one obtain by the optical absorbance spectra.
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 Surfactant Assisted Hydrothermal Synthesis of Single Phase Pyrite FeS2 Nanocrystals written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Iron pyrite nanocrystals with high purity have been synthesized through a surfactant-assisted hydrothermal reaction under optimum pH value. These pyrite nanocrystals represent a new group of well-defined nanoscale structures for high-performance photovoltaic solar cells based on non-toxic and earth abundant materials.
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 Studies of Pyrite FeS2 Nanocrystals and Plasmonic Nanostructures for Low Cost and High Efficiency Inverted Bulk Heterojunction Photovoltaic Cells written by Beau J. Richardson and published by . This book was released on 2015 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solar energy is our most abundant and clean natural energy source which has made photovoltaics (PV) of great interest as a renewable and sustainable energy technology. Organic photovoltaics (OPVs) offer great potential for lower fabrication and materials costs as they are solution processable, compatible with high throughput roll-to-roll printing processes, flexible, lightweight and have tunable material properties. The encompassing goal of this work is to explore new materials, nanostructures and device designs that may aid the development of OPVs towards large scale, low cost and more efficient PV technologies. In the search for new PV materials, pyrite iron disulfide (FeS2) is noticeable as an earth abundant and environmentally benign semiconductor with low procurement costs and advantageous optoelectronic properties. Here, pyrite FeS2 nanocrystals (NCs) were synthesized and deployed in ternary organic-inorganic hybrid bulk-heterojunction (BHJ) solar cells with an inverted architecture. Three device performance regimes are observed when the pyrite NC concentration is varied from 0 to 4 wt% that appear linked to microstructure transitions in the active layer. The addition of FeS2 NCs consistently increased photocurrent and exposure in air actually rectified current leakage resulting in an average 28% increase in power conversion efficiency (PCE) of hybrid devices compared to control devices. The photocurrent enhancement and air-stability demonstrated by this inverted design offer a promising architecture for future pyrite FeS2 NC-based devices. Furthermore, the NC characterizations presented here provide insight to advance pyrite's development as a PV material. Nanostructures of various types can be used to enhance OPV performance. The effects of nanostructured ZnO electron transport layers (ETLs) were studied in high efficiency inverted OPVs on ITO substrates. Nano-ridged and planar ZnO ETLs were formed and consistently high FFs exceeding 70% and PCEs reaching 8.32% were achieved on both types of nanostructures when maintaining optimal active layer thickness. ITO is the most common transparent electrode used in OPVs, yet limited indium reserves and poor mechanical properties of ITO on flexible substrates make it non-ideal for large-scale OPV production. To replace ITO, plasmonic nanostructured electrodes were designed, fabricated and deployed as electrodes in inverted OPV devices. ZnO thickness was found to significantly impact active layer absorption due to resonant cavity effects with the plasmonic nanostructured electrodes. Devices with thinner ZnO ETLs showed PCEs as high as 5.70% and higher JSC's than devices on thicker ZnO. ITO-free, flexible devices on PET showed a PCE of 1.82% and those fabricated on ultrathin and conformable Parylene substrates yielded an initial PCE over 1%. To our knowledge, this is the first time nanopatterned plasmonic electrodes have been applied to highly flexible, ITO-free OPVs. With further fabrication development to improve nanopattern quality on flexible substrates, these designs show promise for highly functioning conformable devices that can be applied to numerous needs for lightweight, ubiquitous power generation.
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 Chalcogenide Based Nanomaterials as Photocatalysts written by Mohammad Mansoob Khan and published by Elsevier. This book was released on 2021-04-07 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chalcogenide-Based Nanomaterials as Photocatalysts deals with the different types of chalcogenide-based photocatalytic reactions, covering the fundamental concepts of photocatalytic reactions involving chalcogenides for a range of energy and environmental applications. Sections focus on nanostructure control, synthesis methods, activity enhancement strategies, environmental applications, and perspectives of chalcogenide-based nanomaterials. The book offers guidelines for designing new chalcogenide-based nanoscale photocatalysts at low cost and high efficiency for efficient utilization of solar energy in the areas of energy production and environment remediation. Provides information on the development of novel chalcogenide-based nanomaterials Outlines the fundamentals of chalcogenides-based photocatalysis Includes techniques for heterogeneous catalysis based on chalcogenide-based nanomaterials
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
Download or read book Pyrite written by Noel Whitley and published by Nova Science Publishers. This book was released on 2013 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photovoltaics Beyond Silicon written by Senthilarasu Sundaram and published by Elsevier. This book was released on 2024-06-28 with total page 819 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photovoltaics Beyond Silicon: Innovative Materials, Sustainable Processing Technologies, and Novel Device Structures presents the latest innovations in materials, processing and devices to produce electricity via advanced, sustainable photovoltaics technologies. The book provides an overview of the novel materials and device architectures that have been developed to optimize energy conversion efficiencies and minimize environmental impacts. Advances in technologies for harnessing solar energy are extensively discussed, with topics including materials processing, device fabrication, sustainability of materials and manufacturing, and the current state-of-the-art. Contributions from leading international experts discuss the applications, challenges and future prospects of research in this increasingly vital field, providing a valuable resource for students and researchers working in this area. Presents a comprehensive overview and detailed discussion of solar energy technology options for sustainable energy conversion Provides an understanding of the environmental challenges to be overcome and discusses the importance of efficient materials utilization for clean energy Looks at how to design materials processing and optimize device fabrication, including metrics such as power-to-weight ratio, effectiveness at EOL compared to BOL, life-cycle analysis
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 Optoelectronics and Spintronics in Smart Thin Films written by James Ayodele Oke and published by CRC Press. This book was released on 2023-12-06 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smart thin films, composed of functional materials deposited in thin layers, have opened new avenues for the development of flexible, lightweight, and high-performance devices. Optoelectronics and Spintronics in Smart Thin Films presents a comprehensive overview of this emerging area and details the current and near future integration of smart thin films in solar cells, and memory storage. Offers an overview of optoelectronics and spintronics. Discusses synthesis of smart nanomaterials. Describes deposition techniques and characterization of thin films. Considers the integration and application of opto-spintronics for technological advancement of solar cells and memory storage devices. Focused on advancing research on this evolving subject, this book is aimed at advanced students, researchers, and engineers in materials, chemical, mechanical, and electrical engineering, as well as applied physics.
Download or read book Solar Cells written by Arturo Morales-Acevedo and published by BoD – Books on Demand. This book was released on 2013-03-06 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decade, photovoltaic (PV) technology has shown the potential to become a major source of power generation for the world - with robust and continuous growth even during times of financial and economic crisis. That growth is expected to continue in the years ahead as worldwide awareness of the advantages of PV increases. However, cost remains as the greatest barrier to further expansion of PV-generated power, and therefore cost reduction is the prime goal of the PV and solar cell investigation. This book intends to contribute to such a purpose by covering a wide range of modern research topics in the solar cell physics and technology fields. The already established -1st generation- silicon solar cell technology, the 2nd generation thin film and the 3rd generation dye sensitized solar cells, including new technologies with very high perspectives for reducing the cost of solar electricity such as CZTS, organic polymer and tandem solar cells based on III-V compounds -under concentrated sunlight- are studied in this book by experts in the field from around the world. At the end, two chapters are also dedicated to the systems engineering, providing a complete PV energy research and application perspectives panorama
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 Synthesis and Characterization of Iron Based Nanoparticles for Novel Applications written by Hafsa Khurshid and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The work in this thesis has been focused on the fabrication and characterization of iron based nanoparticles with controlled size and morphology with the aim: (i) to investigate their properties for potential applications in MICR toners and biomedical field and (ii) to study finite size effects on the magnetic properties of the nanoparticles. For the biomedical applications, core/shell structured iron/iron-oxide and hollow shell nanoparticles were synthesized by thermal decomposition of iron organometallic compounds [Fe(CO) 5] at high temperature. Core/shell structured iron/iron-oxide nanoparticles have been prepared in the presence of oleic acid and oleylamine. Particle size and composition was controlled by varying the reaction parameters during synthesis. The as-made particles are hydrophobic and not dispersible in water. Water dispersibility was achieved by ligand exchange a with double hydrophilic diblock copolymer. Relaxometery measurements of the transverse relaxation time T 2 of the nanoparticles solution at 3 Tesla confirm that the core/shell nanoparticles are an excellent MRI contrast agent using T 2 weighted imaging sequences. In comparison to conventionally used iron oxide nanoparticles, iron/iron-oxide core/shell nanoparticles offer four times stronger T 2 shortening effect at comparable core size due to their higher magnetization. The magnetic properties were studied as a function of particle size, composition and morphology. Hollow nanostructures are composed of randomly oriented grains arranged together to make a shell layer and make an interesting class of materials. The hollow morphology can be used as an extra degree of freedom to control the magnetic properties. Owing to their hollow morphology, they can be used for the targeted drug delivery applications by filling the drug inside their cavity. For the magnetic toners applications, particles were synthesized by chemically reducing iron salt using sodium borohydride and then coated with polyethylene glycol. Parameters such as the reactant concentrations and their flow rate were varied to study the effect of particle size, structure and crystallinity on the magnetic nanoparticles. Many different hydrophilic surfactants and polymers electrolytes were investigated for the particles' stability in water. PSSNa was found to be the best coating agent among all the other investigated polymer and surfactants for particles stability in water. Particles have an average size of 50 nm and magnetization above 150 emu/g. It is anticipated that owing to their high saturation magnetization and magneto crystalline anisotropy, the incorporations of PSSNa coated nanoparticles into the MICR toner can reduce the pigment loading and hence optimize the toner quality. The magnetic properties were studied as a function of particle size, composition and morphology. The saturation magnetization and coercivity was found to be strongly dependent on the particle size and morphology. The estimated effective anisotropy of the particles was found to be much higher than their bulk values because of their morphology and finite size effects. Core/shell particles below an average size of 12 nm display superparamagnetism and exchange bias phenomenon. The hollow morphology can be used as an extra degree of freedom to control magnetic properties. The enormously large number of pinned spins at the inner and outer surface and at the interface between the grain boundaries in hollow nanoparticles, gives rise to a very large value of effective anisotropy in these nanoparticles and measured hyteresis loops are minor loops. The surface spin disorder contribution to magnetic behavior is strongly influenced by the cooling field magnitude.
Download or read book Low cost Nanomaterials written by Zhiqun Lin and published by Springer. This book was released on 2014-06-26 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will cover the most recent progress on the use of low-cost nanomaterials and development of low-cost/large scale processing techniques for greener and more efficient energy related applications, including but not limited to solar cells, energy storage, fuel cells, hydrogen generation, biofuels, etc. Leading researchers will be invited to author chapters in the field with their expertise. Each chapter will provide general introduction to a specific topic, current status of research and development, research challenges and outlook for future direction of research. This book aims to benefit a broad readership, from undergraduate/graduate students to researchers working on renewable energy.
Download or read book Heterogeneous Catalysis for the Synthetic Chemist written by Robert L. Augustine and published by CRC Press. This book was released on 2020-08-11 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work delineates the effect of different reaction variables on the outcome of heterogeneously catalyzed reactions, and explains how to optimize the product yield of specific compounds. Metal catalysis, simple and complex oxides, zeolites and clays are discussed, both as catalysts and as potential supports for catalytically active metals.
