Download or read book Towards High Efficiency and Low Cost Nano structured III V Solar Cells written by Gu Anjia and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: State-of-the-art III-V multijunction solar cells have achieved a record efficiency of 42%, the highest solar-electric conversion efficiency achieved by any technology. This has fueled great interest in the utility sector for large-scale deployment of solar cells. However, III-V solar cells have thus far proven too expensive for widespread terrestrial applications due to the combined cost of substrates, growth processes and materials. Here, we propose a novel III-V solar cell design based on the epitaxial growth of AlGaAs/GaAs on pre-patterned low-cost substrates to provide a path to cost-effective, large-scale deployment. This approach is based on our discovery that the surface kinetics of epitaxial growth by MBE is significantly altered when growing on three dimensional nanostructures instead of planar surfaces. Based on our exploratory results, we present the device design, electrical and optical simulation, and materials growth and device fabrication and characterization of core-shell nanostructured III-V solar cells. We use both bottom-up and top-down approaches to prepare the nanostructured templates in shape of nanowires and nanopyramids. Finite-difference time-domain (FDTD) and Rigorous Coupled Wave Analysis (RCWA) simulation show that the nanostructures have enhanced absorption and much wider incident acceptance angles than their planar counterpart, and outperform planar three-layer anti-reflective coatings. We first demonstrated high quality, single crystal III-V (GaAs and AlGaAs) polar material conformally epi grown on group IV (nanostructured Ge on Si substrate) nonpolar material via MBE and MOVPE (also known as MOCVD) with largely reduced anti-phase domains. We developed complete and mature routines to fabricate a working, single crystalline III-V solar cell on a nanostructured template. The I-V characterization of the fabricated nanostructured GaAs solar cell proves the concept and shows the great potential of making high-efficiency nano-structured III-V solar cells on low-cost substrates.

Download or read book Nanostructures in III V Solar Cells written by Dong Liang and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: From the physics and materials viewpoint, III-V materials are ideal for highly efficient photovoltaic conversion. Their major limitations are cost and resource availability. As industrial planar III-V solar cells continue to set the all-time efficiency records, nanostructured III-V solar cells are now being investigated in academia with the goal to further improve the efficiency and lower the required materials volume and cost. However, most previously investigated nano-structured solar cells suffer from low efficiencies. In this dissertation, I first present optical enhancement in nanopyramid III-V ultra-thin films which can potentially reduce the required materials by one order of magnitude. I then demonstrate significant efficiency improvement in GaAs solar cell. Especially, with an AlGaAs nanocone window layer, a 17%-efficiency nanostructured single-junction solar cell is obtained. The first part of my dissertation focuses on optical engineering and absorption improvement in nanopyramid GaAs ultra-thin film. I demonstrate a double-sided nanopyramid GaAs film that is only 160 nm thick, laminated in a flexible transparent superstrate. Without additional antireflection coatings, this nanopyramid film absorbs over 80% more photons than a planar counterpart with equal thickness at normal incidence and is equivalent to a 1um thick film. At large incident angles, this enhancement can be even greater. With similar light trapping design, III-V solar cell film thickness can be potentially reduced from 3-4 um to 200-300 nm, which could significantly reduce III-V cell cost. The second part of my dissertation focuses on efficiency improvement in III-V nanostructured solar cells. First, GaAs solar cell efficiency enhancement using ZnO nanoparticle antireflection coating is briefly demonstrated. I then demonstrate our work on nanostructured p-n junction solar cells and discuss the challenges for nanostructured solar cell. After this, I propose a nanowindow solar cell design that can overcome these challenges by enhancing both optical and electrical properties. A nanowindow solar cell using a nanocone AlGaAs window layer, a GaAs junction and mesa grid contact is demonstrated with a high energy conversion efficiency of 17.0% and high open circuit voltage of 0.982 V.

Download or read book High Efficiency Nanostructured III V Photovoltaics for Solar Concentrator Application written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrators project seeks to provide new photovoltaic cells for Concentrator Photovoltaics (CPV) Systems with higher cell efficiency, more favorable temperature coefficients and less sensitivity to changes in spectral distribution. The main objective of this project is to provide high efficiency III-V solar cells that will reduce the overall cost per Watt for power generation using CPV systems. This work is focused both on a potential near term application, namely the use of indium arsenide (InAs) QDs to spectrally "tune" the middle (GaAs) cell of a SOA triple junction device to a more favorable effective bandgap, as well as the long term goal of demonstrating intermediate band solar cell effects. The QDs are confined within a high electric field i-region of a standard GaAs solar cell. The extended absorption spectrum (and thus enhanced short circuit current) of the QD solar cell results from the increase in the sub GaAs bandgap spectral response that is achievable as quantum dot layers are introduced into the i-region. We have grown InAs quantum dots by OMVPE technique and optimized the QD growth conditions. Arrays of up to 40 layers of strain balanced quantum dots have been experimentally demonstrated with good material quality, low residual stain and high PL intensity. Quantum dot enhanced solar cells were grown and tested under simulated one sun AM1.5 conditions. Concentrator solar cells have been grown and fabricated with 5-40 layers of QDs. Testing of these devices show the QD cells have improved efficiency compared to baseline devices without QDs. Device modeling and measurement of thermal properties were performed using Crosslight APSYS. Improvements in a triple junction solar cell with the insertion of QDs into the middle current limiting junction was shown to be as high as 29% under one sun illumination for a 10 layer stack QD enhanced triple junction solar cell. QD devices have strong potential for net gains in efficiency at high concentration.

Download or read book Fundamentals and Applications of Nano Silicon in Plasmonics and Fullerines written by Munir H. Nayfeh and published by Elsevier. This book was released on 2018-06-29 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals and Applications of Nano Silicon in Plasmonics and Fullerines: Current and Future Trends addresses current and future trends in the application and commercialization of nanosilicon. The book presents current, innovative and prospective applications and products based on nanosilicon and their binary system in the fields of energy harvesting and storage, lighting (solar cells and nano-capacitor and fuel cell devices and nanoLEDs), electronics (nanotransistors and nanomemory, quantum computing, photodetectors for space applications; biomedicine (substance detection, plasmonic treatment of disease, skin and hair care, implantable glucose sensor, capsules for drug delivery and underground water and oil exploration), and art (glass and pottery). Moreover, the book includes material on the use of advanced laser and proximal probes for imaging and manipulation of nanoparticles and atoms. In addition, coverage is given to carbon and how it contrasts and integrates with silicon with additional related applications. This is a valuable resource to all those seeking to learn more about the commercialization of nanosilicon, and to researchers wanting to learn more about emerging nanosilicon applications. Features a variety of designs and operation of nano-devices, helping engineers to make the best use of nanosilicon Contains underlying principles of how nanomaterials work and the variety of applications they provide, giving those new to nanosilicon a fundamental understanding Assesses the viability of various nanoslicon devices for mass production and commercialization, thereby providing an important source of information for engineers

Download or read book Nanostructured Solar Cells written by Narottam Das and published by BoD – Books on Demand. This book was released on 2017-02-22 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructured solar cells are very important in renewable energy sector as well as in environmental aspects, because it is environment friendly. The nano-grating structures (such as triangular or conical shaped) have a gradual change in refractive index which acts as a multilayer antireflective coating that is leading to reduced light reflection losses over broadband ranges of wavelength and angle of incidence. There are different types of losses in solar cells that always reduce the conversion efficiency, but the light reflection loss is the most important factor that decreases the conversion efficiency of solar cells significantly. The antireflective coating is an optical coating which is applied to the surface of lenses or any optical devices to reduce the light reflection losses. This coating assists for the light trapping capturing capacity or improves the efficiency of optical devices, such as lenses or solar cells. Hence, the multilayer antireflective coatings can reduce the light reflection losses and increases the conversion efficiency of nanostructured solar cells.

Download or read book Nanomaterials for Solar Cell Applications written by Sabu Thomas and published by Elsevier. This book was released on 2019-06-12 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanomaterials for Solar Cell Applications provides a review of recent developments in the field of nanomaterials based solar cells. It begins with a discussion of the fundamentals of nanomaterials for solar calls, including a discussion of lifecycle assessments and characterization techniques. Next, it reviews various types of solar cells, i.e., Thin film, Metal-oxide, Nanowire, Nanorod and Nanoporous materials, and more. Other topics covered include a review of quantum dot sensitized and perovskite and polymer nanocomposites-based solar cells. This book is an ideal resource for those working in this evolving field of nanomaterials and renewable energy. Provides a well-organized approach to the use of nanomaterials for solar cell applications Discusses the synthesis, characterization and applications of traditional and new material Includes coverage of emerging nanomaterials, such as graphene, graphene-derivatives and perovskites

Download or read book Nanostructured Materials for Type III Photovoltaics written by Peter Skabara and published by Royal Society of Chemistry. This book was released on 2017-11-08 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials for type III solar cells have branched into a series of generic groups. These include organic ‘small molecule’ and polymer conjugated structures, fullerenes, quantum dots, copper indium gallium selenide nanocrystal films, dyes/TiO2 for Grätzel cells, hybrid organic/inorganic composites and perovskites. Whilst the power conversion efficiencies of organic solar cells are modest compared to other type III photovoltaic materials, plastic semiconductors provide a cheap route to manufacture through solution processing and offer flexible devices. However, other types of materials are proving to be compatible with this type of processing whilst providing higher device efficiencies. As a result, the field is experiencing healthy competition between technologies that is pushing progress at a fast rate. In particular, perovskite solar cells have emerged very recently as a highly disruptive technology with power conversion efficiencies now over 20%. Perovskite cells, however, still have to address stability and environmental issues. With such a diverse range of materials, it is timely to capture the different technologies into a single volume of work. This book will give a collective insight into the different roles that nanostructured materials play in type III solar cells. This will be an essential text for those working with any of the devices highlighted above, providing a fundamental understanding and appreciation of the potential and challenges associated with each of these technologies.

Download or read book Silicon Heterojunction Solar Cells written by W.R. Fahrner and published by Trans Tech Publications Ltd. This book was released on 2006-08-15 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: The world of today must face up to two contradictory energy problems: on the one hand, there is the sharply growing consumer demand in countries such as China and India. On the other hand, natural resources are dwindling. Moreover, many of those countries which still possess substantial gas and oil supplies are politically unstable. As a result, renewable natural energy sources have received great attention. Among these, solar-cell technology is one of the most promising candidates. However, there still remains the problem of the manufacturing costs of such cells. Many attempts have been made to reduce the production costs of “conventional” solar cells (manufactured from monocrystalline silicon using diffusion methods) by instead using cheaper grades of silicon, and simpler pn-junction fabrication. That is the ‘hero’ of this book; the heterojunction solar cell.

Download or read book Nano Structured Photovoltaics written by Vinod Kumar Khanna and published by CRC Press. This book was released on 2022-12-20 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presenting a comprehensive overview of a rapidly burgeoning field blending solar cell technology with nanotechnology, the book covers topics such as solar cell basics, nanotechnology fundamentals, nanocrystalline silicon-based solar cells, nanotextured-surface solar cells, plasmon-enhanced solar cells, optically-improved nanoengineered solar cells, dye-sensitized solar cells, 2D perovskite and 2D/3D multidimensional perovskite solar cells, carbonaceous nanomaterial-based solar cells, quantum well solar cells, nanowire solar cells and quantum dot solar cells. The book provides an in-depth and lucid presentation of the subject matter in an elegant, easy-to-understand writing style, starting from basic knowledge through principles of operation and fabrication of devices to advanced research levels encompassing the recent breakthroughs and cutting-edge innovations. It will be useful for graduate and PhD students, scientists, and engineers. Key features: * Builds an integrated perspective of photovoltaics by highlighting the essential role of nanotechnology in each type of solar cell. * Performs simplified mathematical analysis of operational mechanisms of nanostructured solar cells supplemented with solved examples. * Enhances learning with clear explanations of technological advances and illustrative diagrams without sacrificing scientific rigor.

Download or read book Semiconductor Nanowires written by J Arbiol and published by Elsevier. This book was released on 2015-03-31 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor nanowires promise to provide the building blocks for a new generation of nanoscale electronic and optoelectronic devices. Semiconductor Nanowires: Materials, Synthesis, Characterization and Applications covers advanced materials for nanowires, the growth and synthesis of semiconductor nanowires—including methods such as solution growth, MOVPE, MBE, and self-organization. Characterizing the properties of semiconductor nanowires is covered in chapters describing studies using TEM, SPM, and Raman scattering. Applications of semiconductor nanowires are discussed in chapters focusing on solar cells, battery electrodes, sensors, optoelectronics and biology. Explores a selection of advanced materials for semiconductor nanowires Outlines key techniques for the property assessment and characterization of semiconductor nanowires Covers a broad range of applications across a number of fields

Download or read book High Efficiency III V Thin Film Solar Cells written by Xiaohan Li (Ph. D.) and published by . This book was released on 2015 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photon management via submicron and subwavelength nanostructures has been extensively studied over the last decade, and has become one of the most important approaches of boosting the energy conversion efficiency for thin-film photovoltaic devices. The incorporation of low dimensional nanostructures, such as GaAs/InGaAs quantum wells, into typical GaAs single-junction cells will extend the cell absorption further into the sub-GaAs bandgap region but usually results in reduced cell open-circuit voltage. As a consequence, various bandgap engineering techniques for improving the energy conversion efficiency for quantum well solar cells have been reported. This dissertation will describe studies of light trapping in multiple GaAs/InGaAs quantum well solar cells via nanostructured front side dielectric coating and back side metal/dielectric contacts, photovoltaic performance enhancement for bulk and flexible thin-film GaAs solar cells through subwavelength nanostructured antireflection coating, and bandgap engineering techniques for GaAs/InGaAs multiple quantum well solar cells. In the study of nanostructured dielectric antireflection coatings, a 5.8% increase in short-circuit current density is observed for the GaAs/In0.3Ga0.7As multiple quantum well cell coated with TiO2 nanostructured coating compared to the cell coated with conventional Si3N4 single-layer antireflection coating even in the presence of high surface recombination. Numerical simulation shows that as high as 13% increase in short-circuit current density can be achieved without surface recombination. In the study of GaAs/In0.3Ga0.7As multiple quantum well solar cells integrated with nanostructured back side metal/dielectric contacts, as high as 2.9% per quantum well external quantum efficiency is achieved, significantly surpassing the 1% per quantum well external quantum efficiency typically observed in quantum well solar cells. In both studies, two major mechanisms contributing to the increased longer wavelength quantum well absorption have been elucidated: Fabry-Perot resonances and scattering into guided optical modes. In application of subwavelength-scale optical nanostructures on bulk and flexible epitaxial lift-off GaAs solar cells for broadband, omnidirectional improvement of photovoltaic performance, 1.1× increase in short-circuit current density is observed for the bulk GaAs cell fully integrated with optical nanostructures compared to the unpatterned cell (1.09× increase in short-circuit current density for flexible epitaxial lift-off GaAs cell) at normal incidence, while 1.67× increase in short-circuit current density is observed (1.52× increase in short-circuit current density is observed for flexible epitaxial lift-off GaAs cell) at 80° angle of incidence. In the study of bandgap engineering strategies for improving the photovoltaic performance for GaAs/InGaAs multiple quantum well solar cells, a quantum well solar cell with graded quantum well depths, which has an average 18% indium concentration in quantum wells, is shown to yield improvements in both open-circuit voltage and short-circuit current density compared to a GaAs/In0.18Ga0.82As quantum well solar cell with constant quantum well depths across the intrinsic region. The results of this study suggest that such an approach can also be implemented in quantum well solar cells with more complex quantum well structures, such as ternary or quaternary quantum wells, where the conduction and valence band offsets of each quantum well can be simultaneously engineered.

Download or read book Fabrication and Investigation of III V Quantum Structured Solar Cells with Fabry P rot Cavity and Nanophotonics in Order to Explore High efficiency Photovoltaic Concepts written by Benoît Behaghel and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past decade, photovoltaics (PV) has become a key player for the future of worldwide energy generation. Innovation in PV is likely to rely on high efficiency PV with flexible and lightweight thin films to enable PV deployement for mobile applications. In the framework of the Japanese-French laboratory “NextPV”, this thesis investigates the development of III-V quantum structured solar cells to explore high-efficiency photovoltaic concepts especially intermediate band solar cells (IBSC). Quantum structured IBSC have proven to be limited by thermal escape at room temperature and by low subbandgap light absorption. Following a consistent approach, we evaluate the topology, thermal escape mechanism, quantum structure and optical absorption of In(Ga)As quantum dots in a wide gap Al0.2GaAs host material. We also characterize quantitatively the device operation and improve the optical design. For a high irradiation, we evidence a hot carrier population in the quantum dots. At the same time, sequential two-photon absorption (S-TPA) is demonstrated both optically and electrically. We also show that S-TPA for both subbandgap transitions can be enhanced by a factor x5-10 with light management techniques, for example by implementation of Fabry-Perot cavities with the different epitaxial transfer methods that we developed. More advanced periodical nanostructures were also fabricated in the case of multi-quantum well solar cells using nanoimprint lithography techniques. Overall we discuss the possibility of realizing intermediate-band-assisted hotcarrier solar cells with light management to open the path for high-efficiency quantum structured IBSC.

Download or read book High efficiency Thin film Crystalline Solar Cells written by Yangsen Kang and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin-film high-efficiency crystalline solar cells are expected to play a significant role as a greener, renewable energy source of the future. Such cells have been extensively studied over the past 10 years. Most of this research focused on developing thinner cells to reduce material usage and improving the optical absorption within the thin absorber. Most recently, the active semiconductor layer can be 10 -- 100 times thinner than conventional solar cells by advanced light trapping. However, an improvement in efficiency in thin-film solar cells had not been previously appreciated and is an equally if not more important enhancement of the cells in addition to materials cost saving. This dissertation presents the device physics of thin-film crystalline solar cells and demonstrates the key design principle to achieve higher efficiency by improving two important parameters: open circuit voltage (Voc) and short circuit current (Jsc). The first part of this thesis focuses on achieving high Voc in thin-film c-Si solar cells and demonstrate the voltage enhancement in thin-film Si solar cells in both theoretical simulation and experimental demonstration. Theoretically, thin cells can significantly increase the carrier concentration by confining photo-carriers into a smaller active region and decrease the recombination by reducing the volume of the active region. This results in higher Voc and efficiency. Experimentally, the first Voc enhancement in thin-film solar cells is demonstrated. The 5 æm thick Si cell achieved a Voc of 649 mV, which is superior to the Voc of any other thin-film (sub-25-æm) Si solar cells reported to date. To further improve efficiency, a carrier selective contact of TiO2/Si was developed to reduce the high carrier recombination at the metal contacts associated with the high carrier centration in thin films. Such a contact demonstrates a contact recombination reduction of 33% and a Voc enhancement of 10 mV compared to a conventional metal contact. The second part mainly discusses high Jsc by applying nanoscale light trapping structures to thin-film c-Si and III-V solar cells. Given the challenges in obtaining low surface recombination and high efficiency in nanostructured solar cells, we demonstrated a nanowindow solar cell design with dielectric or wide bandgap semiconductor material that can overcome these challenges. A SiNx nanostructured dielectric layer can provide both light tapping and surface passivation for Si. A thin Si film with such SiNx layer exhibits

Download or read book Materials for Solar Cell Technologies I written by Inamuddin and published by Materials Research Forum LLC. This book was released on 2021-01-20 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book reviews recent research and new trends in the area of solar cell materials. Topics include fabrication methods, solar cell design, energy efficiency and commercialization of next-generation materials. Special focus is placed on graphene and carbon nanomaterials, graphene in dye-sensitized solar cells, perovskite solar cells and organic photovoltaic cells, as well as on transparent conducting electrode (TCE) materials, hollow nanostructured photoelectrodes, monocrystalline silicon solar cells (MSSC) and BHJ organic solar cells. Also discussed is the use of graphene, sulfides, and metal nanoparticle-based absorber materials. Keywords: Solar Cell, Graphene Nanomaterials, Carbon Nanomaterials, Graphene in Dye-sensitized Solar Cells, Perovskite Solar Cells, Organic Photovoltaic Cells, Transparent Conducting Electrode (TCE) Materials, Hollow Nanostructured Photoelectrodes, Monocrystalline Silicon Solar Cells (MSSC), BHJ Organic Solar Cells, Electrochemical Sensing, Low Band-Gap Materials, Absorber Materials for Solar Cells.

Download or read book Fundamentals of Solar Cell Design written by Inamuddin and published by John Wiley & Sons. This book was released on 2021-08-24 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solar cells are semiconductor devices that convert light photons into electricity in photovoltaic energy conversion and can help to overcome the global energy crisis. Solar cells have many applications including remote area power systems, earth-orbiting satellites, wristwatches, water pumping, photodetectors and remote radiotelephones. Solar cell technology is economically feasible for commercial-scale power generation. While commercial solar cells exhibit good performance and stability, still researchers are looking at many ways to improve the performance and cost of solar cells via modulating the fundamental properties of semiconductors. Solar cell technology is the key to a clean energy future. Solar cells directly harvest energy from the sun’s light radiation into electricity are in an ever-growing demand for future global energy production. Solar cell-based energy harvesting has attracted worldwide attention for their notable features, such as cheap renewable technology, scalable, lightweight, flexibility, versatility, no greenhouse gas emission, environment, and economy friendly and operational costs are quite low compared to other forms of power generation. Thus, solar cell technology is at the forefront of renewable energy technologies which are used in telecommunications, power plants, small devices to satellites. Aiming at large-scale implementation can be manipulated by various types used in solar cell design and exploration of new materials towards improving performance and reducing cost. Therefore, in-depth knowledge about solar cell design is fundamental for those who wish to apply this knowledge and understanding in industries and academics. This book provides a comprehensive overview on solar cells and explores the history to evolution and present scenarios of solar cell design, classification, properties, various semiconductor materials, thin films, wafer-scale, transparent solar cells, and so on. It also includes solar cells’ characterization analytical tools, theoretical modeling, practices to enhance conversion efficiencies, applications and patents.

Download or read book High Efficiency Solar Cells written by Xiaodong Wang and published by Springer Science & Business Media. This book was released on 2013-11-01 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of the effort to increase the contribution of solar cells (photovoltaics) to our energy mix, this book addresses three main areas: making existing technology cheaper, promoting advanced technologies based on new architectural designs, and developing new materials to serve as light absorbers. Leading scientists throughout the world create a fundamental platform for knowledge sharing that combines the physics, materials, and device architectures of high-efficiency solar cells. While providing a comprehensive introduction to the field, the book highlights directions for further research, and is intended to stimulate readers’ interest in the development of novel materials and technologies for solar energy applications.

Download or read book Nanostructured Materials for Type III Photovoltaics written by Mohammad Azad Malik and published by Royal Society of Chemistry. This book was released on 2017-11-08 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will give a collective insight into the different roles that nanostructured materials play in Type III solar cells.