In Situ Polymerizable Lead-Chelating Crown Ether for Lead Leakage Inhibition in Perovskite Solar Cells

While perovskite solar cells (PSCs) have garnered substantial attention owing to the high power conversion efficiency (PCE), light weight, and potential for cost reduction, their long-term stability and the pollution impact on the environment remain significant issues that need to be addressed urgently. The primary challenges in lead-based perovskites are caused by the segregation and migration of Pb 2+ within the perovskite grain boundaries (GBs) and interface during device operation, which accelerate the degradation of perovskite and ultimately result in lead leakage. In this research, the stability of perovskite is improved through the in situ polymerization of DVB18C6, a polymerizable crown ether with selective lead chelating property within the perovskite GBs. The robust GBs formed by DVB18C6 optimize perovskite film defects and suppress device lead leakage. The champion device achieved a PCE of 26.78%, with a Pb 2+ sequestration efficiency (SQE) of 95.14%. By integrating lead-chelating functionality with polymerizable groups, this approach improves the stability of PSCs and effectively mitigates lead leakage.