Dimethyl Ferrocene-Induced Ambient-Processed High-Quality Films toward Efficient Perovskite Solar Cells for...

Metal halide perovskite solar cells (PSCs) have recently made significant progress with power conversion efficiencies (PCEs) boosted from 3.8% to a certified one over 26.1%, partially benefiting from the high-quality perovskite film enabled by the effective one-step spin-coating route. However, an extra antisolvent step with poor controllability and producibility is often involved in such a process, and some intrinsic defects are generated inevitably, especially in ambient atmospheric conditions, thus fundamentally limiting the commercialization of PSCs. Here, we introduce 1,1'dimethyl ferrocene into methylammonium lead halide precursor, which could not only recover the defects within perovskite film but also simplify the process without the extra antisolvent step. Accordingly, a dense and uniform perovskite film with large grains has been obtained under ambient conditions, which has much lower defect density, better stability against moisture penetration, and enhanced thermal tolerance than the control one, delivering a champion PCE of 16.92%. Current work sheds light on the simplified air-processed strategy for high-quality perovskite films, which might pave the way for exploring efficient and stable PSCs toward industrial applications.