Crystallization Regulation Enables High-Performance Perovskite Solar Cells

CsPbI<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>Br-based perovskite solar cells (PSCs) have attracted widespread attention due to their excellent light absorption ability and photothermal stability. However, the conventional one-step method for preparing CsPbI<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>Br perovskite devices suffers from several limitations related to poor crystal quality, including small grain size, high density of iodide vacancies, and inadequate phase stability. Herein, we introduce sodium 4-amino-2-hydroxybenzoate (SAHB) into the precursor solution and regulate the crystallization process, revealing the importance of crystallization regulation on the perovskite film quality and device performance. The modified devices achieved a high efficiency of 17.33% and demonstrated good stability. This work provides guidance and reference for crystal regulation and defect passivation in inorganic PSCs.