Comparison of the lead-leakage in Pb-Sn hybrid perovskite solar cells and Pb-based perovskite solar cells

Abstract: Perovskite solar cells exhibit outstanding device performance and photovoltaic potential in recent ten years. However, the photoactive layer of the majority of perovskite solar cells with outstanding efficiency currently contains toxic lead. Although perovskite solar cells will be encapsulated prior to application to enhance the device's stability and prevent lead leakage, it is still possible for the devices to be broken or exposed to the environment during actual use. Correspondingly, Pb may enter water or soil through rainfall, posing health risks to humans and other creatures. To prepare perovskite solar cell devices with both high performance and low toxicity, current research concentrates primarily on Pb-Sn hybrid perovskite solar cells as Sn is less toxic than Pb from an environmental standpoint. To intuitively compare the lead leakage of Pb-based perovskite solar cells and Pb-Sn hybrid perovskite solar cells, this study simulated the lead leakage scenario under heavy rainfall conditions using self-prepared, good-performance solar cell devices. Our results indicate that Pb-Sn hybrid perovskite solar cells have less lead leakage than Pb-based perovskite solar cells. The lead leakage concentration of Pb-Sn hybrid perovskite solar cells was 36.8% (in the dripping test) and 41.2% (in the soaking test) lower than that of Pb-based perovskite solar cells.