Crystallization kinetics‐driven defect landscape in wide‐bandgap perovskite solar cells: Mechanistic elucidation and multiscale regulation strategies

Abstract Wide‐bandgap perovskite solar cells (WBG‐PSCs) are the core devices to break through the efficiency limit of single junction cells by constructing tandem devices. However, recent studies have shown that the poor quality of perovskite films due to uncontrolled rapid crystallization leads to severe open‐circuit voltage ( V OC ) loss, phase separation, and high defect density. These problems seriously restrict the performance and stability of the device. This review provides a comprehensive understanding of the defects caused by the rapid crystallization of wide‐bandgap perovskite film, and elucidates their effects on device stability and V OC loss from the mechanism. Subsequently, the latest progress of crystallization regulation strategies was systematically summarized, and the underlying mechanism of crystallization regulation was analyzed. Finally, prospects and challenges are proposed to provide insights for future research and technological progress.