Recent Advancing Progress of Inverted Perovskite Solar Cells Through Functional Buried Interface Engineering

Inverted perovskite solar cells (PSCs) have emerged as a highly promising photovoltaic architecture due to their excellent operational stability, simplified fabrication, and compatibility with tandem integration. While surface passivation and top interface optimization have been extensively studied, the buried interface between hole transport layer and perovskite absorber has recently been recognized as a critical yet underexplored factor controlling device efficiency and long‐term stability. This review systematically examines the fundamental roles, characterization techniques, and engineering strategies of buried interfaces in inverted PSCs. We first analyze defect formation, energy‐level alignment, strain accumulation and crystallization dynamics at the buried interface, followed by advanced characterization approaches that enable direct probing of interfacial chemical and electronic properties. We then summarize recent progress in buried interface engineering, including crystallization modulation, chemical passivation, energy‐level tuning and emerging methods such as molecular extrusion and porous insulator contacts. Finally, we highlight remaining challenges in scaling buried interface engineering from small‐area devices to large‐area modules, emphasizing scalable processing, uniform interfacial modification and long‐term operational stability. This review aims to provide a comprehensive framework and guidance for the rational design of next‐generation high‐efficiency and durable inverted PSCs.