Recent Progress of Critical Interface Engineering for Highly Efficient and Stable Perovskite Solar Cells

Organic–inorganic lead halide perovskite solar cells (PSCs) have demonstrated enormous potential as a new generation of solar‐based renewable energy. Although their power conversion efficiency (PCE) has been boosted to a spectacular record value, the long‐term stability of efficient PSCs is still the dominating concern that hinders their commercialization. Notably, interface engineering has been identified as a valid strategy with extraordinary achievements for enhancing both efficiency and stability of PSCs. Herein, the latest research advances of interface engineering for various interfaces are summarized, and the basic theory and multifaceted roles of interface engineering for optimizing device properties are analyzed. As a highlight, the authors provide their insights on the deposition strategy of interlayers, application of first‐principle calculation, and challenges and solutions of interface engineering for PSCs with high efficiency and stability toward future commercialization. Perovskite solar cells (PSCs) have demonstrated enormous potential as next generation of photovoltaic technologies. Herein, the latest advances of interfacial materials for highly efficient and stable PSCs are summarized with organized classification. The theory and multifaceted roles of interface engineering are analyzed and insights on the deposition strategy of interlayers and outlook of interface engineering for PSCs toward commercialization are provided.