Cu2ZnSnS4薄膜成分-结构-性能关系的理论模拟与电化学方法的可控制备

项目名称： Cu2ZnSnS4薄膜成分-结构-性能关系的理论模拟与电化学方法的可控制备

项目编号： No.51472020

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 李志林

作者单位： 北京化工大学

项目金额： 85万元

中文摘要： Cu2ZnSnS4薄膜因元素资源丰富、能带结构适用于太阳能电池的吸收层受到广泛关注。但现有真空沉积、溶胶-凝胶、连续离子层吸附反应等制备方法存在设备、工艺复杂、制备成本高、周期长、尺寸受限等问题。本项目采用电化学方法制备Cu2ZnSnS4薄膜，针对其成分、结构调控等性能优化的关键因素，基于理论计算研究薄膜成分、纯相稳定性、点缺陷种类和浓度、晶粒尺寸等结构因素与薄膜能带结构等光电性质的内在关系，提出薄膜结构设计优化的普适性原则。在此基础上，基于配位化学理论选择络合剂和缓冲剂，优化电解液组成，调节电沉积过程的电化学参数，实现其一步法电沉积制备和成分调控。进而基于计算结果、相图和薄膜中各相的热力学函数值等对非化学计量比成分的薄膜进行不同程度的退火，实现其结构的精确调控，从而实现其光电性能的针对性调控。进行Cu2ZnSnS4薄膜异质结的组装，从光电转换效率的实际提高研究薄膜电化学可控制备的可行性。

中文关键词： Cu2ZnSnS4；薄膜；电化学制备；结构调控；理论模拟；光电性能

英文摘要： Cu2ZnSnS4 film materials receive wide attention because of their abundant element resources and suitable energy band structure for the absorption layer of solar cells. But their existing preparation methods, such as vacuum deposition, sol-gel method, successive ionic layer adsorption and reaction, have many problems such as complex equipment and technique, high cost and long period of preparation, and confined size, etc. In this project, Cu2ZnSnS4 films will be prepared with electrochemical method. The intrinsic relationships between the composition, structure factors (such as the stability of the pure phase, species and content of point defects, grain size), and energy band structure and other photovoltaic properties of Cu2ZnSnS4 films will be researched based on theoretical calculations, in the light of the crucial factors of property optimization, such as the control of compositon and structure. Universal principles of the structure design and optimization of the films will be advanced. On such basis, the electrolyte composition will be optimized by the selection of the complexing agents and buffer agents according to coordination chemistry theory. The electrochemical parameters of the electrodeposition process will be adjusted. One-step electrodeposition preparation and composition control of Cu2ZnSnS4 films will be achieved by the electrolyte design and the parameter adjustment. The precise structure control of the films with non-stoichiometric composition will be achieved by the further annealing with different extent according to the calculation results, phase diagrams and themodynamic function data of different phases, so as to achieve targeted control of photovoltaic properties of the films. Heterojunction with Cu2ZnSnS4 films will be further prepared to research the feasibility of their controllable electrochemical preparation through the actual promotion of the photoelectric transformation efficiency.

英文关键词： Cu2ZnSnS4 film;Electrochemical preparation;Structure control;Theoretical simulation;Photovoltaic propteries