氯掺杂对CH3NH3PbI3太阳能电池材料气相生长机理、界面结构及其性能影响的同步辐射研究

项目名称： 氯掺杂对CH3NH3PbI3太阳能电池材料气相生长机理、界面结构及其性能影响的同步辐射研究

项目编号： No.U1532140

项目类型： 联合基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 罗派峰

作者单位： 合肥工业大学

项目金额： 64万元

中文摘要： 近年来由于氯掺杂CH3NH3PbI3钙钛矿薄膜具有优异的结晶成膜和电荷传输性能而引起广泛关注。但鉴于其取向生长特性，常规表征尚不能进行精确结构解析，导致掺杂元素Cl的具体作用还不清楚，相应薄膜制备工艺、生长机理及界面结构等关键问题也亟待解决。针对上述难题，本项目拟创新性地采用Cl元素协助的气相沉积方法，可控制备Cl掺杂钙钛矿薄膜；结合先进同步辐射实验技术，系统研究其晶体结构和电子能带结构，进而与所制电池性能相关联。项目将主要探索实验参数对薄膜质量和器件性能的影响规律；采用同步辐射SRPES、NEXAFS、EXAFS及GIWAXS，结合密度泛函理论计算，重点研究掺杂离子格位占据、材料晶格畸变、结晶生长取向、原子局域环境、电子能带及界面结构等重要信息。通过本项目的实施，可望建立合理的材料成分-结构-物性关系模型，揭示该材料的生长机理和Cl元素作用机制，为研发高性能钙钛矿电池提供重要的理论依据。

中文关键词： 物理性能；局域结构；可控制备；x射线吸收谱；密度泛函

英文摘要： In recent years, chlorine doped CH3NH3PbI3 perovskite films have attracted extensive attentions due to their excellent crystallinity and charge transport properties. But its oriented growth characteristic prevents the accurately determination of the fully crystal structure by conventional characterization methods, which leads that the exact role of doping element Cl is still unclear so far, and some key issues, such as the thin-film preparation technology, growth mechanism, and interface structure, need to be solved. In view of above questions, a novel Cl-assisted vapor deposition method is innovatively used to prepare controllably the chlorine doped perovskite films in this proposal, and the crystal structure and the electronic band structure are systematically investigated by the advanced synchrotron radiation experimental techniques, which is associated with the performance of the prepared solar cells. We will mainly focus on the effect of the experimental parameters on the thin-film quality and device performance. Some important information, such as the occupying position of doping ions, lattice distortion, crystal growth orientation, local atomic environment, and the structures of the electronic band and interface, will be studied in-depth by the synchrotron radiation-based SRPES, NEXAFS, EXAFS, and GIWAXS techniques, combining with the density functional theory calculations. Based on the successful implementation of this project, it is expected to built the reasonable composition-structure-performance relation model, and reveal the growth mechanism of this kind of materials and the detailed role of Cl element, and provide important theoretical basis for the development of high-performance perovskite solar cells.

英文关键词： Physical property;Local structure;Controllable preparation;X-ray absorption spectrum;Density functional theory