Solution-Processed Chalcogenide Photovoltaic Thin Films PDF Download

Author: Marcos Antonio Santana Andrade Junior
Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 0

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Book Description
Chalcogenides-based thin film solar cells are great competitors to beat high efficiencies as silicone solar cells. The chalcogenides that have been commonly used as absorber materials are CIS, CIGS, and CZTS. They present some advantages of having a direct and tunable band gap, high absorption coefficient and respectable efficiency to cost ratio. Solution processable deposition approaches for the fabrication of solar cells attracts a great deal attention due to its lower capital cost of the manufacturing than the vacuum-based techniques. In this chapter, we detail the use of a low-cost method of deposition for the chalcogenide thin films by spin-coating and spray-coating, which is already widely employed in several fields of industries.

Author: Zhaoning Song
Publisher:
ISBN:
Category : Chalcogenides
Languages : en
Pages : 225

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Book Description
Photovoltaics (PV) is increasingly recognized as an important component of renewable energy sources after the rapid progress in the last decade due to increasing energy demand and reducing manufacturing costs. Despite the enormous growth of the PV market, the present solar technologies that are dominated by crystalline silicon are still limited by the relatively more expensive cost of electricity compared with power generation in the conventional fossil fuel plants. Consequently, there is an urgent need to increase the performance and reduce the manufacturing costs of solar cells. While the commercial thin film solar cells (CdTe and CuInGaSe2) have already demonstrated high efficiencies, the current fabrication processes heavily rely on intensive capital investment on expensive vacuum-based techniques. To reduce solar module costs, solution-processing techniques have been proposed as a promising route towards low cost, high throughput, large scale manufacturing of high efficiency thin film solar cells. In this thesis, we investigate the solution-processing of copper indium chalcogenides and methylammonium lead halides materials and their applications as high efficiency photovoltaic cells. In the first approach, we develop an ultrasonic spray deposition system to prepare the CuIn(S,Se)2 thin films. Spray deposition is a controllable, scalable, and high throughput process that is suitable for industrial manufacturing. Here we first explore the Cu-In-S films prepared by an aqueous precursor ink. By controlling the precursor composition, we fabricate PV devices consisting of the n-type In2S3 window and p-type CuInS2 absorber layers and demonstrate 2% efficiency in the preliminary devices. After replacing the aqueous ink by a hydrazine-based precursor solution and incorporating a selenization process, we are able to fabricate high quality CuIn(S,Se)2 thin film solar cells in both conventional substrate and the backwall superstrate configurations. The efficiency of 7.2% has been achieved in the sprayed CuIn(S,Se)2 devices in the substrate configuration. In the second approach, we investigate solution-processing of the inorganic-organic hybrid metal halide perovskites. We study the impact of reaction temperature and precursor composition on the formation of perovskite materials and propose a pseudo binary phase diagram to guide the processing of the materials. We develop a laser beam induced current (LBIC) technique to spatially resolve the photocurrent collection in the solution-processed devices. Processing defects and impurities phases have been identified as the origins of lower current generation. On the basis of these results, we apply advanced processing techniques in device processing and obtain the champion perovskite device with a 16% efficiency. Additionally, we image the photocurrent generated in the sub-cells of the Si/perovskite tandem devices. The result can be used to improve the design the device structure. Finally, to study the stability of perovskite solar cells, we investigate the spatial and temporal evolution of photocurrent collection across the devices and observe the partially reversible phase transition of perovskite in humid air.

Author: Wenbing Yang
Publisher:
ISBN:
Category :
Languages : en
Pages : 108

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Book Description
The barrier to utilize solar generated electricity mainly comes from their higher cost relative to fossil fuels. However, innovations with new materials and processing techniques can potentially make cost effective photovoltaics. One such strategy is to develop solution processed photovoltaics which avoid the expensive vacuum processing required by traditional solar cells. The dissertation is mainly focused on two absorber material system for thin film solar cells: chalcopyrite CuIn(S, Se)2 (CISS) and kesterite Cu2ZnSn(S, Se)4 organized in chronological order. Chalcopyrite CISS is a very promising material. It has been demonstrated to achieve the highest efficiency among thin film solar cells. Scaled-up industry production at present has reached the giga-watt per year level. The process however mainly relies on vacuum systems which account for a significant percentage of the manufacturing cost. In the first section of this dissertation, hydrazine based solution processed CISS has been explored. The focus of the research involves the procedures to fabricate devices from solution. The topics covered in Chapter 2 include: precursor solution synthesis with a focus on understanding the solution chemistry, CISS absorber formation from precursor, properties modification toward favorable device performance, and device structure innovation toward tandem device. For photovoltaics to have a significant impact toward meeting energy demands, the annual production capability needs to be on TW-level. On such a level, raw materials supply of rare elements (indium for CIS or tellurium for CdTe) will be the bottleneck limiting the scalability. Replacing indium with zinc and tin, earth abundant kesterite CZTS exhibits great potential to reach the goal of TW-level with no limitations on raw material availability. Chapter 3 shows pioneering work towards solution processing of CZTS film at low temperature. The solution processed devices show performances which rival vacuum-based techniques and is partially attributed to the ease in controlling composition and CZTS phase through this technique. Based on this platform, comprehensive characterization on CZTS devices is carried out including solar cells and transistors. Especially defects properties are exploited in Chapter 4 targeting to identify the limiting factors for further improvement on CZTS solar cells efficiency. Finally, molecular structures and precursor solution stability have been explored, potentially to provide a universal approach to process multinary compounds.

Author: Roland Scheer
Publisher: John Wiley & Sons
ISBN: 3527633723
Category : Technology & Engineering
Languages : en
Pages : 398

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Book Description
This first comprehensive description of the most important material properties and device aspects closes the gap between general books on solar cells and journal articles on chalcogenide-based photovoltaics. Written by two very renowned authors with years of practical experience in the field, the book covers II-VI and I-III-VI2 materials as well as energy conversion at heterojunctions. It also discusses the latest semiconductor heterojunction models and presents modern analysis concepts. Thin film technology is explained with an emphasis on current and future techniques for mass production, and the book closes with a compendium of failure analysis in photovoltaic thin film modules. With its overview of the semiconductor physics and technology needed, this practical book is ideal for students, researchers, and manufacturers, as well as for the growing number of engineers and researchers working in companies and institutes on chalcogenide photovoltaics.

Author: Benjamin D. Weil
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
CIGS is currently the highest efficiency chalcogenide absorber, with a record cell efficiency of 20.3%. One of the main challenges of CIGS manufacturing is reducing costs and scaling up manufacturing. The use of toxic elements (Se, Te, Cd) and rare earth elements (In, Te) further complicates the materials processing. The development of non-toxic, earth abundant materials to replace these technologies is underway. Furthermore, there is a need to develop scalable and high-throughput manufacturing techniques that could reduce costs and improve manufacturing of chalcogenide solar cells. Solution-based deposition techniques are widely considered to be a route to low-cost, high-throughput photovoltaic device fabrication. Nanoparticle based inks are one means of achieving low-cost and high-throughput solution-processed devices. I study the properties of CuInS2 nanoparticles and their application to solar cell fabrication. I also establish a methodology for a highly scalable deposition process and report the synthesis of an air-stable, vulcanized ink from commercially available precursors. Using this air-stable solution process, solar cells are made with an absorber layer that is flat, contaminant-free, and composed of large-grained CuInS2. I demonstrate an initial power efficiency of 2.15%. To address the challenge of reducing elemental toxicity and the use of rare elements in chalcogenide solar cells, I will discuss some alternative absorbers that don't contain Indium, Cadmium, Tellurium, or Selenium. I demonstrate a 2.2% Cu2SnS3/CdS solar cell using rapid thermal processing and address the challenges facing this material to improve efficiency.

Author: K.L. Chopra
Publisher: Springer Science & Business Media
ISBN: 9780306411410
Category : Science
Languages : en
Pages : 630

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Book Description
"You, 0 Sun, are the eye of the world You are the soul of all embodied beings You are the source of all creatures You are the discipline of all engaged in work" - Translated from Mahabharata 3rd Century BC Today, energy is the lifeline and status symbol of "civilized" societies. All nations have therefore embarked upon Research and Development pro grams of varying magnitudes to explore and effectively utilize renewable sources of energy. Albeit a low-grade energy with large temporal and spatial variations, solar energy is abundant, cheap, clean, and renewable, and thus presents a very attractive alternative source. The direct conver sion of solar energy to electricity (photovoltaic effect) via devices called solar cells has already become an established frontier area of science and technology. Born out of necessity for remote area applications, the first commercially manufactured solar cells - single-crystal silicon and thin film CdS/Cu2S - were available well over 20 years ago. Indeed, all space vehicles today are powered by silicon solar cells. But large-scale terrestrial applications of solar cells still await major breakthroughs in terms of discovering new and radical concepts in solar cell device structures, utilizing relatively more abundant, cheap, and even exotic materials, and inventing simpler and less energy intensive fabrication processes. No doubt, this extraordinary challenge in R/D has led to a virtual explosion of activities in the field of photovoltaics in the last several years.

Author: Eric Bergmann
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Solution processing offers many key advantages to the manufacturing of photovoltaic cells. This includes lower costs, higher throughput and lower temperature conditions resulting in shorter energy payback times and better scalability. Solar cells developed using these techniques then offer greater potential to fill the growing demand for low cost and sustainable energy production. Presented in this thesis is the characterization of each primary interface in solution-deposited Cu2BaSnSxSe4-x (CBTSSe) solar cells using photoelectron spectroscopy techniques. This material is set to improve upon high efficiency predecessor Cu2ZnSnSxSe4-x (CZTSSe) materials by suppressing inherent antisite defect formation through dissimilar ionic-sizes and coordination mismatch. From the electron affinity (EA) values determined by ultraviolet and inverse photoelectron spectroscopies a large conduction band offset of -0.6 eV was measured at the buffer/absorber (CdS/CBTSSe) interface, meaning the conduction band edge of CdS is significantly lower than that of CBTSSe. A cliff-like band profile of this magnitude can promote charge carrier recombination at this interface, lowering the open circuit voltage of the photovoltaic cell and therefore reducing its power conversion efficiency. It is then suggested, based on these findings, that lower electron affinity electron transport materials need to be developed for future optimization of these devices.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 137

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Book Description
Avui en dia, la major part de la industria fotovoltaica està basada en el silici. Aquesta és una tecnologia provada i robusta, però, a causa de l'alt cost dels wafers de silici, el seu potencial de reducció de costos sembla limitat. Així, s'ha desenvolupat una segona generació de cel.les solars, formada per capes primes de semiconductors inorgànics, que gràcies al consum reduït de material semiconductor permet la fabricació de cel·les solars de baix cost. Les tecnologies de capa prima són actualment comercials i presenten eficiències records de fins a 20%, a escala de laboratori. No obstant això, en general els semiconductors de banda prohibida directa, CdTe i CIGS, contenen elements tòxics i poc abundants, com In, Ga o Cd. Una excel.lent alternativa a aquests materials és el CZTS, ja que està format per elements no tòxics i abundants. Aquesta tesi explica el treball fet en la preparació i caracterització de capes primes de CIGS i CZTS mitjançant tècniques de processat en solució, utilitzant tintes de nanopartícules preparades prèviament mitjançant síntesis col·loïdal. Les etapes seguides i detallades en aquesta tesi són les següents: 1. Obtenció d'una solució de nanopartícules de CIGS i CZTS mitjançant síntesi col·loïdal. 2. Preparació de capes primes de CIGS i CZTS usant tècniques de processat en solució mitjançant les nanopartícules de CIGS i CZTS. S'ha establert la composició de la tinta amb la qual obtenim capes sense defectes superficials i lliures d'esquerdes. 3. Seguidament, s'han establert els paràmetres per realitzar el correcte tractament tèrmic per tal d'obtenir un material cristal·lí. 4. Finalment un cop establertes les condicions per obtenir capes primes amb les propietats òptimes per al funcionament d'una cel.la fotovoltaica, procedirem al muntatge de la mateixa i a la mesura dels paràmetres fotovoltaics aixi com la seva eficiència mitjançant simulador solar.

Author: Beddiaf Zaidi
Publisher: BoD – Books on Demand
ISBN: 1839699051
Category : Technology & Engineering
Languages : en
Pages : 114

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Book Description
Thin film photovoltaic-based solar modules produce power at a low cost per watt. They are ideal candidates for large-scale solar farms as well as building-integrated photovoltaic applications. They can generate consistent power, not only at elevated temperatures but also on cloudy, overcast days and at low sun angles.Thin film photovoltaics are second-generation solar cells produced by depositing one or more thin layers, or thin films, of photosensitive material on a suitable substrate such as glass, polymer, or metal. Thin film solar cells are based on various materials such as cadmium telluride (CdTe), copper indium gallium diselenide (CIGS), and amorphous thin film silicon (a-Si, TF-Si) are commercially used in several conventional and advanced technologies.

Author: Stephen Thacker Connor
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 99

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Book Description
In recent years, the field of photovoltaics has become increasingly important due to rising energy demand and climate change. While most solar cells are currently composed of crystalline silicon, devices with thinner films of inorganic absorber materials might allow production at a greater scale due to their lower materials cost. In particular, thin films of CuInS2 are promising solar absorber materials due to their high efficiencies and low required thicknesses. However, the fabrication of thin film solar cells currently requires expensive vacuum techniques. As an alternative, solution-based deposition techniques have been proposed as a route to low-cost and high-throughput electronic device fabrication. I have studied how film growth depends on solutuion deposited precursor film quality, with the goal of producing large grained films of CuInS2 through solution processing. In the first approach, we used solvothermal decomposition of organometallic precursors at moderate temperatures to produce nanoparticles of CuInS2. Thin films of these nanoparticles were cast onto molybdenum coated glass and further processed to create CuInS2 solar cells. We found that performance was dependent on film porosity, grain size, and stoichiometry of the nanoparticles. Films with grain sizes of ~200nm were attained, from which 1.3% efficient solar cells were made. In addition, we showed that this synthesis could be extended to produce CuInS2 nanoparticles with partial substitution of Fe, Zn, and Ga. In the second approach, we synthesized an air-stable hybrid organometallic/nanoparticle ink at room temperature in ambient conditions through a vulcanization reaction. This ink could be coated onto substrates in smooth layers, and further reactive annealing formed large grained CuInS2 films. This process was characterized, and a correlation between residual carbon and grain growth was found. Additionally, the chemical transformation between precursor layers and final sulfide thin film was analyzed, with an emphasis on the difference between sulfurization and selenization. We demonstrated that the sulfurization process was producing morphological defects due to its nucleation limited growth mechanism. However, it was modified to more closely resemble the diffusion limited selenization mechanism, thus producing flat films of CuInS2 with grain sizes of ~500nm.