Download or read book Nanostructured Extremely Thin Absorber Solar Cells written by Eugen Zimmermann and published by . This book was released on 2013 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interface Engineering of Sb2S3 based Extremely Thin Absorber Solar Cells by Atomic Layer Deposition written by Pascal Büttner and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Extremely Thin Absorber Solar Cells written by Hasti Majidi and published by . This book was released on 2017 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: A typical extremely thin absorber (ETA) cell comprises an extremely thin absorber layer at the interface between nanostructured, interpenetrating n-type and p-type semiconductors. Compared to planar photovoltaics, the large surface area of the nanostructured interface allows a thinner absorber layer to be used without sacrificing absorber volume. Photogenerated charges must be separated at the absorber interfaces before they recombine. Shorter distances for charge separation in ETA cells allow using materials with lower purity and higher defect densities, enabling use of inexpensive, solution-based processing methods. We report on electrodeposition of CdSe coatings onto ZnO nanowire arrays and determine the effect of processing conditions on material properties such as morphology and microstructure. We show that room-temperature electrodeposition enables growth of CdSe coatings that are uniform, and conformal with precise control over thickness and microstructure. Optimal range of current density was determined to achieve uniform and conformal coatings. Absorbers thinner than the charge collection length reduce bulk recombination and enhance charge separation at the interface. The charge collection length is directly related to the microstructure of the absorber coating. We report on the crystallite growth of electrodeposited CdSe coatings on ZnO nanowires during annealing. Both in situ transmission electron microscopy (TEM) and x-ray diffraction (XRD) reveal that the nanocrystal size increases from ~3 to ~10 nm upon annealing at 350 C for 1 h and then to more than 30 nm during another 1 h annealing at 400 C. Increased crystallite size, comparable to the coating thickness, shows a nearly two-fold improvement in power conversion efficiency upon annealing. In addition to the crystallinity of the coating, the absorber thickness affects the charge separation in ETA cells. Coatings that are too thin show poor light harvesting. However, too thick coatings show inefficient charge separation. We demonstrated optimum thickness of CdSe in the planar ETA cell. In addition, extremely thin coatings suffer from large interfacial recombination. Severe shunting in very thin absorbers is tackled by applying an ultra-thin (5 nm) coating of CdS on ZnO nanowires before CdSe electrodeposition. Interface engineering in ETA cells leads to five times improvement in the power conversion efficiency.

Download or read book Wet chemical Deposited Inorganic Extremely Thin Absorber Solar Cells written by Olivia Niitsoo and published by . This book was released on 2009 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Zinc Oxide Nanostructured Extremely Thin Absorber Solar Cells written by Leah Spangler and published by . This book was released on 2013 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extremely thin absorber (ETA) solar cells are a relatively new and promising technology that could potentially lead to lower cost solar cells by using cheaper, more abundant materials and solution based processing steps. In this thesis, two aspects of a zinc oxide (ZnO) nanostructured solar cell with a cadmium selenide (CdSe) absorber layer were studied. The first was an attempt to control the density of ZnO nanowires using polystyrene (PS) microspheres, and the second incorporated a cadmium sulfide (CdS) buffer layer to improve solar cell characteristics. Using simple techniques of vertical deposition and dipcoating, PS microspheres were deposited onto ZnO seeded substrates. The desired close packed hexagonal monolayer was obtained using vertical deposition, but the monolayer was not uniform over the entire substrate. Dipcoating yields a very uniform deposition of PS microspheres, but a dense pack can only be achieved with a fast withdrawal rate and slow, controlled evaporation after dipcoating. When growing nanowires using the typical chemical bath deposition technique, it was found that the PS microspheres were unable to block the growth of ZnO nanowires. A CdS buffer layer was incorporated into the ETA cell by using the successive ionic layer adsorption and reaction (SILAR) technique. It was confirmed by both visual and UV-vis inspection that increasing the number of SILAR cycles increases CdS thickness. Scanning electron microscopy (SEM) of 33 cycles of CdS showed that aggregates form on top of the nanowires, which are not present after only 16 cycles. The CdS thickness after 16 cycles was measured using transmission electron microscopy (TEM) to be 5 nm, corresponding to a rate of deposition of 3.12 Å/cycle. Incorporating the CdS layer into both the ZnO nanowire/CdSe structure and indium tin oxide (ITO)/CdSe structure showed improved solar cell characteristics and decreased shunting. This improvement could result from an improved interface between the ZnO/CdSe and ITO/CdSe. In the case of the ZnO structure, CdS may block etching of ZnO, which is known to occur in the CdSe electrodeposition bath. In both structures, the improvement could also be a result of improved band alignment in the cell, favoring charge separation and transport.

Download or read book Synthesis and Characterization of CuSCN for Extremely Thin Absorber Solar Cells written by Thinh Le and published by . This book was released on 2011 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interfacial Engineering and Charge Carrier Dynamics in Extremely Thin Absorber Solar Cells written by Michael Edley and published by . This book was released on 2016 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photovoltaic energy is a clean and renewable source of electricity; however, it faces resistance to widespread use due to cost. Nanostructuring decouples constraints related to light absorption and charge separation, potentially reducing cost by allowing a wider variety of processing techniques and materials to be used. However, the large interfacial areas also cause an increased dark current which negatively affects cell efficiency. This work focuses on extremely thin absorber (ETA) solar cells that used a ZnO nanowire array as a scaffold for an extremely thin CdSe absorber layer. Photoexcited electrons generated in the CdSe absorber are transferred to the ZnO layer, while photogenerated holes are transferred to the liquid electrolyte. The transfer of photoexcited carriers to their transport layer competes with bulk recombination in the absorber layer. After charge separation, transport of charge carriers to their respective contacts must occur faster than interfacial recombination for efficient collection. Charge separation and collection depend sensitively on the dimensions of the materials as well as their interfaces. We demonstrated that an optimal absorber thickness can balance light absorption and charge separation. By treating the ZnO/CdSe interface with a CdS buffer layer, we were able to improve the Voc and fill factor, increasing the ETA cell's efficiency from 0.53% to 1.34%, which is higher than that achievable using planar films of the same material. We have gained additional insight into designing ETA cells through the use of dynamic measurements. Ultrafast transient absorption spectroscopy revealed that characteristic times for electron injection from CdSe to ZnO are less than 1 ps. Electron injection is rapid compared to the 2 ns bulk lifetime in CdSe. Optoelectronic measurements such as transient photocurrent/photovoltage and electrochemical impedance spectroscopy were applied to study the processes of charge transport and interfacial recombination. With these techniques, the extension of the depletion layer from CdSe into ZnO was determined to be vital to suppression of interfacial recombination. However, depletion of the ZnO also restricted the effective diffusion core for electrons and slowed their transport. Thus, materials and geometries should be chosen to allow for a depletion layer that suppresses interfacial recombination without impeding electron transport to the point that it is detrimental to cell performance. Thin film solar cells are another promising technology that can reduce costs by relaxing material processing requirements. CuInxGa(1-x)Se (CIGS) is a well studied thin film solar cell material that has achieved good efficiencies of 22.6%. However, use of rare elements raise concerns over the use of CIGS for global power production. CuSbS2 shares chemistry with CuInSe2 and also presents desirable properties for thin film absorbers such as optimal band gap (1.5 eV), high absorption coefficient, and Earth-abundant and non-toxic elements. Despite the promise of CuSbS2, direct characterization of the material for solar cell application is scarce in the literature. CuSbS2 nanoplates were synthesized by a colloidal hot-injection method at 220 ℗ʻC in oleylamine. The CuSbS2 platelets synthesized for 30 minutes had dimensions of 300 nm by 400 nm with a thickness of 50 nm and were capped with the insulating oleylamine synthesis ligand. The oleylamine synthesis ligand provides control over nanocrystal growth but is detrimental to intercrystal charge transport that is necessary for optoelectronic device applications. Solid-state and solution phase ligand exchange of oleylamine with S2- were used to fabricate mesoporous films of CuSbS2 nanoplates for application in solar cells. Exchange of the synthesis ligand with S2- resulted in a two order of magnitude increase in 4-point probe conductivity. Photoexcited carrier lifetimes of 1.4 ns were measured by time-resolved terahertz spectroscopy, indicating potential for CuSbS2 as a solar cell absorber material.

Download or read book Nanostructured Extremely Thin Absorber ETA Hybrid Solar Cell Fabrication Optimization and Characterization written by Darcy Erin Lambert and published by . This book was released on 2011 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traditional sources of electrical energy are finite and can produce significant pollution. Solar cells produce clean energy from incident sunlight, and will be an important part of our energy future. A new nanostructured extremely thin absorber solar cell with 0.98% power conversion efficiency and maximum external quantum efficiency of 61% at 650 nm has been fabricated and characterized. This solar cell is composed of a fluorine-doped tin oxide base layer, n-type aluminum doped zinc oxide nanowires, a cadmium selenide absorber layer, poly(3-hexylthiophene) as a p-type layer, and thermally evaporated gold as a back contact. Zinc oxide nanowire electrodeposition has been investigated for different electrical environments, and the role of a zinc oxide thin film layer has been established. Cadmium selenide nanoparticles have been produced and optimized in-house and compared to commercially produced nanoparticles. Argon plasma cleaning has been investigated as a method to improve electronic behavior at cadmium selenide interfaces. The thermal anneal process for cadmium selenide nanoparticles has been studied, and a laser anneal process has been investigated. It has been found that the most efficient solar cells in this study are produced with a zinc oxide thin film, zinc oxide nanowires grown under constant -1V bias between the substrate material and the anode, cadmium selenide nanoparticles purchased commercially and annealed for 24 hours in the presence of cadmium chloride, and high molecular weight poly(3-hexylthiophene) spin-coated in a nitrogen environment.

Download or read book Organic and Hybrid Solar Cells written by Lukas Schmidt-Mende and published by Walter de Gruyter GmbH & Co KG. This book was released on 2016-05-24 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the increasing world-energy demand there is a growing necessity for clean and renewable energy. The sun being one of the most abundant potential sources accounts for less than 1% of the global energy supply. The market for solar cells is one of the most strongly increasing markets, even though the prize of conventional solar cells is still quite high. New emerging technologies, such as organic and hybrid solar cells have the potential to decrease the price of solar energy drastically. This book offers an introduction to these new types of solar cells and discusses fabrication, different architectures and their device physics on the bases of the author's teaching course on a master degree level. A comparison with conventional solar cells will be given and the specialties of organic solar cells emphasized.

Download or read book Thin Film Solar Cells From Earth Abundant Materials written by Subba Ramaiah Kodigala and published by Newnes. This book was released on 2013-11-14 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamental concept of the book is to explain how to make thin film solar cells from the abundant solar energy materials by low cost. The proper and optimized growth conditions are very essential while sandwiching thin films to make solar cell otherwise secondary phases play a role to undermine the working function of solar cells. The book illustrates growth and characterization of Cu2ZnSn(S1-xSex)4 thin film absorbers and their solar cells. The fabrication process of absorber layers by either vacuum or non-vacuum process is readily elaborated in the book, which helps for further development of cells. The characterization analyses such as XPS, XRD, SEM, AFM etc., lead to tailor the physical properties of the absorber layers to fit well for the solar cells. The role of secondary phases such as ZnS, Cu2-xS,SnS etc., which are determined by XPS, XRD or Raman, in the absorber layers is promptly discussed. The optical spectroscopy analysis, which finds band gap, optical constants of the films, is mentioned in the book. The electrical properties of the absorbers deal the influence of substrates, growth temperature, impurities, secondary phases etc. The low temperature I-V and C-V measurements of Cu2ZnSn(S1-xSex)4 thin film solar cells are clearly described. The solar cell parameters such as efficiency, fill factor, series resistance, parallel resistance provide handful information to understand the mechanism of physics of thin film solar cells in the book. The band structure, which supports to adjust interface states at the p-n junction of the solar cells is given. On the other hand the role of window layers with the solar cells is discussed. The simulation of theoretical efficiency of Cu2ZnSn(S1-xSex)4 thin film solar cells explains how much efficiency can be experimentally extracted from the cells. - One of the first books exploring how to conduct research on thin film solar cells, including reducing costs - Detailed instructions on conducting research

Download or read book Nanostructured Materials for Solar Energy Conversion written by Tetsuo Soga and published by Elsevier. This book was released on 2006-12-14 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructured Materials for Solar Energy Conversion covers a wide variety of materials and device types from inorganic materials to organic materials. This book deals with basic semiconductor physics, modelling of nanostructured solar cell, nanostructure of conventional solar cells such as silicon, CIS and CdTe, dye-sensitized solar cell, organic solar cell, photosynthetic materials, fullerene, extremely thin absorber (ETA) solar cell, quantum structured solar cell, intermediate band solar cell, carbon nanotube, etc. including basic principle and the latest results. There are many books written on conventional p-n junction solar cells, but few books focus on new concepts in this area.* Focuses on the use of nanostructured materials for solar energy* Looks at a wide variety of materials and device types* Covers both organic and inorganic materials

Download or read book Thin Film Solar Cells written by Jef Poortmans and published by John Wiley & Sons. This book was released on 2006-10-02 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin-film solar cells are either emerging or about to emerge from the research laboratory to become commercially available devices finding practical various applications. Currently no textbook outlining the basic theoretical background, methods of fabrication and applications currently exist. Thus, this book aims to present for the first time an in-depth overview of this topic covering a broad range of thin-film solar cell technologies including both organic and inorganic materials, presented in a systematic fashion, by the scientific leaders in the respective domains. It covers a broad range of related topics, from physical principles to design, fabrication, characterization, and applications of novel photovoltaic devices.

Download or read book Electrochemical Characterization of CdSe coated ZnO Nanowire Extremely thin absorber Solar Cells written by Treavor Zachary Jones and published by . This book was released on 2014 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Introduction to Nano Solar Cells written by Ning Dai and published by CRC Press. This book was released on 2024-02-27 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the applications of nanomaterials and nanostructures in photovoltaic solar cells, elaborates how they can help achieve high photoelectric conversion efficiency, and introduces readers to the important work done in this field. It covers the basic physical properties of semiconductors and nanomaterials, as well as the formation and characteristics of the p–n junction and the heterojunction; the basic working principle and structures of nano photovoltaic cells; the important parts of nano photovoltaic cells, namely nano surface trapping and electrodes; nano solar cells based on quantum dots, quantum wires, and organic-inorganic hybrid nano photovoltaic cells; and some reported high-efficiency photovoltaic cells. It also discusses various device structures and important growth techniques for obtaining nanomaterials for solar cells. The book will serve as a useful reference or textbook for researchers, teachers, engineers, and graduate students.

Download or read book Wave Propagation and Scattering in Random Media written by Akira Ishimaru and published by Elsevier. This book was released on 2013-06-11 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wave Propagation and Scattering in Random Media, Volume 1: Single Scattering and Transport Theory presents the fundamental formulations of wave propagation and scattering in random media in a unified and systematic manner, as well as useful approximation techniques applicable to a variety of different situations. The emphasis is on single scattering theory and transport theory. The reader is introduced to the fundamental concepts and useful results of the statistical wave propagation theory. This volume is comprised of 13 chapters, organized around three themes: waves in random scatterers, waves in random continua, and rough surface scattering. The first part deals with the scattering and propagation of waves in a tenuous distribution of scatterers, using the single scattering theory and its slight extension to explain the fundamentals of wave fluctuations in random media without undue mathematical complexities. Many practical problems of wave propagation and scattering in the atmosphere, oceans, and other random media are discussed. The second part examines transport theory, also known as the theory of radiative transfer, and includes chapters on wave propagation in random particles, isotropic scattering, and the plane-parallel problem. This monograph is intended for engineers and scientists interested in optical, acoustic, and microwave propagation and scattering in atmospheres, oceans, and biological media.

Download or read book Synthesis and Characterization of CdSe coated ZnO Nanowires for Extremely Thin Absorber Solar Cells written by Ishai Padawer and published by . This book was released on 2009 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thin Film Silicon Solar Cells written by Arvind Victor Shah and published by CRC Press. This book was released on 2010-08-19 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photovoltaic technology has now developed to the extent that it is close to fulfilling the vision of a "solar-energy world," as devices based on this technology are becoming efficient, low-cost and durable. This book provides a comprehensive treatment of thin-film silicon, a prevalent PV material, in terms of its semiconductor nature, startin