Mitigating Potential Lead Leakage Risk of Perovskite Solar Cells by Device Architecture Engineering from Exterior to Interior

Perovskite solar cells (PSCs) have made significant breakthroughs in the past decade in view of efficiency, stability, and large-area manufacturing. So far, the toxicity of lead in perovskite poses a significant concern as to whether and how the technology roadmap should be pursued. In this Review, we first briefly overview the toxicity of Pb in PSCs to humans, animals, and ecosystems. Then, we introduce the life cycles of PSCs and depict the possible circumstances when the human body could be exposed to Pb in PSCs. What's more, we provide a comprehensive discussion on the recent strategies to mitigate Pb leakage by device architecture engineering from device exterior to interior (i.e., trapping Pb in encapsulation layers, charge transport layers and perovskite layers). Finally, we conclude this Review by providing several strategies for the reduction of potential Pb leakage risks.