Chromium‐Based Metal–Organic Framework as A‐Site Cation in CsPbI₂Br Perovskite Solar Cells

Abstract Inorganic CsPbI_xBr_3−x perovskite solar cells (PSCs) have gained enormous interest due to their excellent thermal stabilities. However, their intrinsically poor moisture stability hampers their further development. Herein, a chromium‐based metal–organic framework group is intercalated inside the inorganic PbI framework, resulting in a new multiple‐dimensional electronically coupled CsPbI₂Br perovskite. In this structurally and electronically coupled perovskite, the π‐conjugated terpyridyl can delocalize the excited valence electrons of metal Cr³⁺ ion, enabling multi‐interactive charge‐carrier transport channels within CsPbI₂Br perovskites. The stability and efficiency of the produced devices are substantially enhanced in comparison to their counterparts with only a pristine CsPbI₂Br active layer. The optimized all‐inorganic PSC yields a power conversion efficiency (PCE) as high as 17.02%. Remarkably, the stabilized device retains 80% of its PCE after 1000 h in the ambient atmosphere. This study provides a new paradigm toward addressing the stability challenge of the inorganic perovskite while enhancing its carrier transport ability.