Structural Properties and Stability of Inorganic CsPbI₃ Perovskites

All inorganic lead halide perovskites (ILHPs) have recently become one of the research hotspots in the field of photovoltaics. Due to the absence of weakly bonded organic components, ILHPs exhibit excellent thermal stability compared with the hybrid organic–inorganic perovskites. However, the low structural stability against ambient conditions still limits their practical applications. Herein, the phase stability and structural properties of the inorganic CsPbI₃ are discussed, followed by a comprehensive review of strategies to improve the performance and stability of CsPbI₃ perovskite solar cells (PSCs) with respect to material engineering and device configuration engineering. Finally, the challenges of inorganic PSCs and the promising directions to further improve their efficiency and stability are discussed.