Supramolecular host-guest complexation creates a “lead cage” for efficient and eco-friendly perovskite solar cells

Perovskite solar cells' lead toxicity and leakage are key obstacles to commercialization. Here, we introduce a diazapolyoxamacrobicycle structure of cryptand 222 (C222) into the perovskite precursor solution to obtain high-quality films. The abundant diazapolyoxamacrobicycles in C222 can effectively coordinate with Pb^2 + and form hydrogen bonds with FA⁺ in perovskite, thereby reducing the defect density, suppressing non-radiative recombination, and mitigating lead leakage. As a result, C222-based PSCs achieve a remarkable power conversion efficiency (PCE) of 25.34 % (0.1 cm²) and 23.78 % at a larger area (1.0 cm²), retain over 90 % of its initial PCE after 1500 h of continuous maximum power point tracking (MPPT) under simulated AM 1.5 illumination. Furthermore, the adsorption equilibrium capacity (qe) of C222 is 23.58 mg/g, with an adsorption rate constant (k₂) of 0.035 g (mg/min), indicating a lower adsorption potential barrier for anchoring sites, causing an effectively prevention of lead leakage.