Li Zhenzhen, Liu Xiaolong, Xu Jia, Liao Yinjie, Zhao Hang, Zhang Bing, Liu Shengzhong Frank, Yao Jianxi
State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, Beijing Key Laboratory of Energy Safety and Clean Utilization , North China Electric Power University , Beijing 102206 , People's Republic of China.
Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science & Engineering , Shaanxi Normal University , Xi'an 710119 , People's Republic of China.
J Phys Chem Lett. 2019 Aug 15;10(16):4587-4595. doi: 10.1021/acs.jpclett.9b01822. Epub 2019 Jul 31.
All-inorganic perovskite materials emerge to be potential promising candidates for photoelectric applications. However, their instability to moisture has seriously limited future applications. It is imperative to develop new fabrication methods to make the perovskite films moisture-tolerant. In this work, it is demonstrated that both crystallinity and photoelectronic performance of the CsPbIBr ( < 1) perovskite were enhanced with the existence of excess CsBr and employing moisture treatment. An intermediate product of CsIBr/CsPbIBr was obtained by using an extra amount of CsBr, and the structural evolution toward a uniform CsPbIBr layer (as the Br incorporation, the mole ratio increases from to ) was initiated by moisture treatment, forming new (PbX) octahedra with the bonding of CsIBr to Pb. Attributed to the homogeneity of the stoichiometry and crystallinity, the photovoltaic performance of the moisture-treated perovskite films was improved, with the open-circuit voltage increased from 0.97 to 1.10 V and the power conversion efficiency from 10.89 to 13.09%.
全无机钙钛矿材料成为光电应用中潜在的有前景的候选材料。然而，它们对水分的不稳定性严重限制了未来的应用。开发新的制备方法以使钙钛矿薄膜具有耐湿性势在必行。在这项工作中，结果表明，通过存在过量的CsBr并采用湿气处理，CsPbIBr（<1）钙钛矿的结晶度和光电子性能均得到增强。通过使用额外量的CsBr获得了CsIBr/CsPbIBr的中间产物，并且通过湿气处理引发了向均匀的CsPbIBr层（随着Br的掺入，摩尔比从增加到）的结构演变，通过CsIBr与Pb的键合形成了新的（PbX）八面体。由于化学计量和结晶度的均匀性，湿气处理的钙钛矿薄膜的光伏性能得到改善，开路电压从0.97 V增加到1.10 V，功率转换效率从10.89%提高到13.09%。
