Inorganic‐Derived 0D Perovskite Induced Surface Lattice Arrangement for Efficient and Stable All‐Inorganic Perovskite Solar Cells

Abstract The inverted inorganic CsPbI 3 perovskite solar cells (PSCs) are prospective candidates for next‐generation photovoltaics owing to inherent robust thermal/photo‐stability and compatibility for tandems. However, the performance and stability of the inverted CsPbI 3 PSCs fall behind the n‐i‐p counterparts due to poor energetic alignment and abundant interfacial defect states. Here, an inorganic 0D Cs 4 PbBr 6 with a good lattice strain arrangement is implemented as the surface anchoring capping layer on CsPbI 3 . The Cs 4 PbBr 6 perovskite induces enhanced electron‐selective junction and thus facilitates efficient charge extraction and effectively inhibits non‐radiative recombination. Consequently, the CsPbI 3 PSCs with Cs 4 PbBr 6 demonstrate the highest power conversion efficiency (PCE) of CsPbI 3 ‐based inverted PSCs, reaching 21.03% PCE from a unit cell and 17.39% PCE from a module with a 64 cm 2 aperture area. Furthermore, the resulting devices retain 92.48% after 1000 h under simultaneous 1‐sun and damp heat (85 °C / 85% relative humidity) environment.