CZTS的界面分相行为、钝化机制及其对器件光伏性能的影响

Due to the narrow range of the thermodynamic stability of the CZTS, it is difficult to obtain high quality CZTS thin film with well-crystallization, controllable composition, and homogeneous structure and phase. The phase separation could easily take place during the process of forming CZTS thin film and then producing dualistic phase products such as SnS or ZnS, in which would result the deep energy band gap and become the recombination center of photoelectron-hole pairs in the devices. From the perspectives of the existing research, the split-phase CZTS is closely related to the entrainment of heterogeneous materials at the interface. Accordingly, this project plan to employ coating method to prepare CZTS on the surface of Glass/Mo, then systematically study the phase separation behavior and mechanism of CZTS on the Mo layer. On this basis, it is designed to establish a Mo/DL/CZTS model by creating DL at the interface of Mo/CZTS, explore the interfacial passivated behavior and the relevant impact to the phase separation behavior by passivation, and furthermore confirm the performance impact on battery device photovoltaic.

由于CZTS的热力学稳定区间较窄，致使获得结晶良好、成份受控、结构和物相均一的高质量CZTS薄膜较困难。在CZTS薄膜生长过程中容易发生分相而出现SnS、ZnS等二元相，这些二元相在器件中形成深能级带隙，成为光电子-空穴对的复合中心。从已有的研究来看，CZTS分相与界面异质材料的诱导作用密切相关。因此，本项目拟采用涂覆法在Glass/Mo上制备CZTS，研究CZTS在Mo层上的分相行为和机理；在此基础上通过在Mo/CZTS界面插入钝化层（DL）的方式建立Mo/DL/CZTS研究模型，研究界面钝化行为以及钝化作用对分相行为的影响和对电池器件光伏性能的影响。

针对CZTS薄膜太阳电池界面易分相并对转换效率造成重大影响的问题，采用涂覆法研究了CZTS薄膜的制备，以及三种不同晶体结构的CZTS的热力学稳定区间和光电特性；建立Glass/Mo/CZTS研究模型，研究了Mo层的显微结构特征（择优取向）对CZTS薄膜组成和结构的影响；研究了在Mo层表面进行钝化对CZTS组成和结构的影响。掌握了CZTS薄膜相变规律，初步探明了界面对CZTS分相和织构影响规律，初步探索了钝化对CZTS界面分相的影响，建立了界面分相控制措施。制备出转换效率达到11.2%的CZTS薄膜太阳电池。发表论文6篇，其中SCI收录4篇，EI收录1篇，正在投稿SCI论文2篇，以及待整理数据若干；申请发明专利6项，获授权专利4项。培养博士1名，硕士研究生8名。