A Catalyst‐Like System Enables Efficient Perovskite Solar Cells
Yuqian Yang, Guodong Li, Lichen Zhao, Pengju Tan, Yu Li, Shunde Li, Lina Tan, Chunyan Deng, Shibo Wang, Zhenzhu Zhao, Chengjian Yuan, Honghe Ding, Liang Chen, Junfa Zhu, Yong Guan, Cheng‐Hung Hou, Pengyi Tang, Q. Li, Hong Liu, Yingguo Yang, Antonio Abate, Jing‐Jong Shyue, Jihuai Wu, Thomas P. Russell, Qin Hu
Abstract
High-quality perovskite films are essential for achieving high performance of optoelectronic devices; However, solution-processed perovskite films are known to suffer from compositional and structural inhomogeneity due to lack of systematic control over the kinetics during the formation. Here, the microscopic homogeneity of perovskite films is successfully enhanced by modulating the conversion reaction kinetics using a catalyst-like system generated by a foaming agent. The chemical and structural evolution during this catalytic conversion is revealed by a multimodal synchrotron toolkit with spatial resolutions spanning many length scales. Combining these insights with computational investigations, a cyclic conversion pathway model is developed that yields exceptional perovskite homogeneity due to enhanced conversion, having a power conversion efficiency of 24.51% for photovoltaic devices. This work establishes a systematic link between processing of precursor and homogeneity of the perovskite films.