Stable perovskite solar cells with 23.12% efficiency and area over 1 cm2 by an all-in-one strategy

To realize the commercialization of perovskite solar cells (PSCs), it is required to overcome the remaining challenges in device enlargement and operational stability. Here, we report an all-in-one strategy by integrating the oxidation of hole-transport material (HTM) with the formation of the passivation layer, which simultaneously solved the stability issues caused by HTM oxidation and realized the uniform defects in passivation over a large area. The resulting devices achieved a certified PCE of 23.12% on average with an aperture area of 1.04 cm2 and are reproducible with high operational stability because of the exclusion of air exposure, hygroscopic Li-TFSI, and the lithium-based wastes, maintaining ca. 90% of their initial PCEs after operation at the maximum power point under continuous 1 sun illumination for 1,600 h. Our strategy simplifies the fabrication process of PSCs, which is compatible with commercial-scale methods, offering facile access to efficient and stable large-area PSCs.