Mitigating the Lead Leakage of High-Performance Perovskite Solar Cells via In Situ Polymerized Networks

Despite the remarkable performance progress being made, environmental concerns remain for lead halide perovskite solar cells (PSCs) because of the possible water dissolution of lead ions (Pb2+) into the environment. Herein, we succeed in mitigating Pb leakage of PSCs, for the first time, via implanting in situ polymerized networks into perovskites. We strategically transform the dormant monomer additives into chelating polymer networks within perovskite layers, which not only passivate the defects of perovskite but also protect Pb2+ from water dissolution. The resultant perovskite–polymer hybrids have successfully enabled state-of-art power conversion efficiencies (PCEs) for inverted PSCs (PCE of 22.1%) and large-area modules (PCE of 15.7%). More importantly, up to 94% rejection rate of Pb2+ dissolution is achieved upon directly immersing the unencapsulated devices into water, which reasonably simulates the exposure of the broken and unprotected panels to torrential rain for 24 h.