Recent Advances on High‐Performance Inverted CsPbI ₃ Perovskite Solar Cells and Their Tandem Application

ABSTRACT Inverted CsPbI 3 perovskite solar cells (PSCs) have attracted more attention in single‐junction and tandem solar cells, owing to the optimal band‐gap, superior photothermal stability, and device architecture compatible with commercial bottom cells such as CuInSe 2 and silicon. However, their development is hindered by challenges including the complex phase transition process, interfacial energy‐level mismatch, unpassivated defects, and the suboptimal transport layer. A comprehensive understanding of the material characteristics, phase transition mechanisms, and interface state of CsPbI 3 is therefore essential to address these issues. In this review, we systematically examine the phase‐transition dynamics of CsPbI 3 and summarize recent advances in fabricating efficient and stable inverted CsPbI 3 PSCs, focusing on: (1) Regulation of the phase transition and bulk crystallization; (2) Management of interface energy‐level and defect passivation; (3) Selection of hole transport materials and their integration in tandem solar cells. Finally, we outline the remaining challenges and future perspectives to guide the development of high‐performance and operationally stable inverted inorganic perovskite‐based single‐junction and tandem photovoltaics.