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

项目负责人：Shenoy， vivek提案编号：1235870机构：布朗大学标题：目标：地球丰富的Cu2ZnSnSxSe4-x （CZTS）薄膜太阳能电池的晶界结构和电子特性为了使太阳能广泛使用，需要低成本，高通量和可靠的光伏生产方法。薄膜太阳能电池材料特别令人感兴趣，因为它们可以以一种成本有效的方式制造。Cu2ZnSnSxSe4-x （CZTS）由于使用Zn和Sn这两种低成本且富含地球的元素，被认为是薄膜器件中有前途的吸收层候选材料之一。晶体组分的晶界对性能有影响。目前还没有系统的实验数据和理论模型来研究CZTS晶界的结构和取向分布。pi将使用多尺度方法，结合实验技术进行晶界表征，第一性原理计算和遗传算法进行结构确定，动力学蒙特卡罗和分子动力学模拟进行分离动力学建模。IBM高分辨率透射电子显微镜（HRTEM）将通过与密度函数计算模拟的TEM图像进行比较来识别晶界取向。采用电子背散射衍射（EBSD）方法测量晶界随取向的分布。扫描透射电子显微镜（STEM）模式下的能谱（EDS）可以提供晶界附近原子组成（富Cu /贫Cu）的信息。该项目将为研究生和本科生提供一个在领先的工业实验室进行实验工作和发展先进计算技能的机会。在计算方法方面取得的进展将包括在PI创建的课程中，以促进动手模拟经验。该项目将从这些项目中提供交互式软件模块给K-12教师和学生参加布朗？暑假高中。最后，考虑到开发有效方法以提高基于czts的太阳能电池的转换效率所投入的大量精力和资源，从提高原子水平对晶界的理解中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.