GOALI: Structure and Electronic Properties of Grain Boundaries in Earth Abundant Cu2ZnSnSxSe4-x (CZTS) Thin Film Solar Cells

Pi：Shenoy，Vivek Proposal编号：1235870机构：布朗大学标题：GALI：地球晶界的结构和电子性质丰富的Cu2ZnSnSxSe4-x(CZTS)薄膜太阳能电池需要低成本、高通量和可靠的光伏生产方法，以便广泛使用太阳能。薄膜太阳能电池材料特别令人感兴趣，因为它们可以以具有成本效益的方式制造。Cu2ZnSnSxSe4-x(CZTS)由于使用了锌和锡这两种低成本、富含稀土的元素，被认为是最有前途的薄膜器件吸收层候选材料之一，其性能受晶界的影响。目前还没有关于CZTS晶界结构和取向分布的系统实验数据或理论模型。PI将使用多尺度方法，将晶界表征的实验技术与第一性原理计算和遗传算法相结合用于结构确定，并使用动力学蒙特卡罗和分子动力学模拟来模拟偏析动力学。用IBM高分辨透射电子显微镜(HRTEM)与密度泛函模拟的电子显微镜图像进行比较，以确定晶界取向。电子背散射衍射(EBSD)方法将被用来测量晶界随取向的分布。扫描透射电子显微镜(STEM)模式下的光谱学(EDS)可以提供有关晶界附近原子组成(铜的丰富/贫富)的信息。该项目将为研究生和本科生提供在领先的工业实验室进行实验工作和发展高级计算技能的机会。在计算方法方面取得的进展将包括在PI为促进实践模拟体验而创建的课程中。该项目将为参加布朗？S暑期高中的K-12教师和学生提供这些项目的互动软件模块。最后，鉴于在开发高效方法以提高CZTS太阳能电池的转换效率方面投入了大量的精力和资源，通过提高原子水平对晶界的了解而获得的见解可能会产生经济影响，特别是在半导体和光伏能源行业。

PI: Shenoy, VivekProposal Number: 1235870Institution: Brown UniversityTitle: GOALI: Structure and Electronic Properties of Grain Boundaries in Earth Abundant Cu2ZnSnSxSe4-x (CZTS) Thin Film Solar CellsLow-cost, high-throughput, and reliable photovoltaic production methods are needed in order to make solar energy widely available. Thin-film solar cell materials are of particular interest because they can be fabricated in a cost- effective manner. Cu2ZnSnSxSe4-x (CZTS) is regarded as one of the promising candidates of the absorber layer used in thin film devices because of the use of Zn and Sn, two low-cost and earth-abundant elements.The performance is affected by the grain boundaries in the crystalline components. Currently there is no systematic experimental data or theoretical models on the structure and orientation distribution of grain boundaries in CZTS. The PIs will use a multi-scale approach that combines experimental techniques for the grain boundary characterization with first-principles calculations and genetic algorithms for structure determination and kinetic Monte Carlo and molecular dynamics simulations for modeling segregation kinetics. IBM High Resolution Transmission Electron microscopy (HRTEM) will be used to identify the grain boundary orientation by comparing with the TEM images simulated by using density functional calculations. The Electron BackScatter Diffraction (EBSD) method will be employed to measure the distribution of grain boundary as a function of orientation. Spectroscopy (EDS) in the Scanning Transmission Electron Microscopy (STEM) mode can provide information about the atomic composition near grain boundary (Cu rich/poor).The project will provide an opportunity for graduate and undergraduate students to both carry out experimental work in a leading industrial lab and to develop advanced computational skills. The progress made in the computational methods will be included in the course that the PI has created to promote hands-on simulation experience. The project will provide interactive software modules from these projects to K-12 teachers and students participating in Brown?s summer high school. Finally, given the large effort and resources that are being invested in the development of efficient methods to improve the conversion efficiency of CZTS-based solar cells, insights gained from increased atomic level understanding of grain boundaries could have economic impact, particularly in the semiconductor and photovoltaic energy industry.