Affiliation:
1. 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 and Engineering Shaanxi Normal University No. 620, West Chang'an Avenue Xi'an 710119 P. R. China
2. Materials Genome Institute Shanghai University Shanghai 200444 P. R. China
3. Key Laboratory of Photoelectric Conversion and Utilization of Solar Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning P. R. China
Abstract
AbstractThe characteristics of the soft component and the ionic‐electronic nature in all‐inorganic CsPbI3‐xBrx perovskite typically lead to a significant number of halide vacancy defects and ions migration, resulting in a reduction in both photovoltaic efficiency and stability. Herein, we present a tailored approach in which both anion‐fixation and undercoordinated‐Pb passivation are achieved in situ during crystallization by employing a molecule derived from aniline, specifically 2‐methoxy‐5‐trifluoromethylaniline (MFA), to address the above challenges. The incorporation of MFA into the perovskite film results in a pronounced inhibition of ion migration, a significant reduction in trap density, an enhancement in grain size, an extension of charge carrier lifetime, and a more favorable alignment of energy levels. These advantageous characteristics contribute to achieving a champion power conversion efficiency (PCE) of 22.14 % for the MFA‐based CsPbI3‐xBrx perovskite solar cells (PSCs), representing the highest efficiency reported thus far for this type of inorganic metal halide perovskite solar cells, to the best of our knowledge. Moreover, the resultant PSCs exhibits higher environmental stability and photostability. This strategy is anticipated to offer significant advantages for large‐area fabrication, particularly in terms of simplicity.