Progress and Perspective on Inorganic CsPbI2Br Perovskite Solar Cells

Over the past few years, all‐inorganic perovskite solar cells (PSCs), especially CsPbI2Br PSCs, have received much attention because of their excellent thermal stability and a suitable trade‐off between light absorption and higher phase stability among the family of inorganic perovskites. In this progress report, the realization of highly efficient and stable CsPbI2Br PSCs is summarized through preparation process, additive engineering, interface modification, and transport material selection. Furthermore, the application of CsPbI2Br in tandem solar cells and its large‐area development are highlighted. Finally, the challenges and outlook of CsPbI2Br PSCs are discussed for further performance improvement and future practical deployment. CsPbI2Br perovskite solar cells (PSCs) have received much attention because of the excellent thermal stability. In view of the existing problems of CsPbI2Br PSCs, optimization methods including preparation process, additives, modification materials, carrier transport layers, application in tandem solar cells, and development of large area PSCs are summarized. Finally, the challenges and outlook of CsPbI2Br PSCs are discussed.