文献类型：期刊文献

英文题名：Stoichiometric Dissolution of Defective CsPbI2Br Surfaces for Inorganic Solar Cells with 17.5% Efficiency

作者：Liu, Xinyi[1];Lian, Huijun[1];Zhou, Ziren[1];Zou, Can[1];Xie, Jin[1];Zhang, Fan[1];Yuan, Haiyang[1];Yang, Shuang[1];Hou, Yu[1,2];Yang, Hua Gui[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Key Lab Ultrafine Mat, Minist Educ,Shanghai Engn Res Ctr Hierarch Nanoma, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Math, Shanghai 200237, Peoples R China

年份：2022

卷号：12

期号：14

外文期刊名：ADVANCED ENERGY MATERIALS

收录：;EI(收录号：20220811687008);WOS:【SCI-EXPANDED(收录号:WOS:000758050400001)】；

基金：This work was financially supported by the National Ten Thousand Talent Program for Young Top-notch Talent, National Natural Science Fund for Excellent Young Scholars (52022030), National Natural Science Fund for Distinguished Young Scholars (51725201), National Natural Science Foundation of China (51972111, 51902185), International (Regional) Cooperation and Exchange Projects of the National Natural Science Foundation of China (51920105003), Innovation Program of Shanghai Municipal Education Commission (E00014), the Fundamental Research Funds for the Central Universities (JKD01211623, JKVD1211041), the Fundamental Research Funds of Free Exploration of Science, Technology and Innovation Commission of Shenzhen Municipality (2021Szvup039), and Shanghai Engineering Research Center of Hierarchical Nanomaterials (18DZ2252400).

语种：英文

外文关键词：inorganic perovskites; solar cells; ionic liquids; surface passivation; structural modulations; wide bandgap

摘要：The existence of a defective area composed of nanocrystals and amorphous phases on a perovskite film inevitably causes nonradiative charge recombination and structural degradation in perovskite photovoltaics. In this study, a stoichiometric etching strategy for the top surface of a defective cesium lead halide perovskite is developed by using ionic liquids. The dissolution of the original defective area substantially exposes the underlying perovskite, which is a high-quality surface with retained stoichiometry and lattice continuity. The ionic liquid molecules are adsorbed on the perovskite surface via Coulombic interactions and passivate the undercoordinated surface lead centers. Such a structural modulation considerably reduces the trap density of the perovskite devices and enables a record power conversion efficiency of 17.51% and an open-circuit voltage of 1.37 V of the CsPbI2Br cell with a perovskite bandgap of 1.88 eV. This work provides a novel technical route to improve the efficiency and environmental resilience of perovskite-based optoelectronic devices.