Pernicious effects and management of lead leakage from perovskite solar cells

Abstract

Perovskite solar cells (PSCs) represent new-generation solar technology, demonstrating attractive properties of low material cost and simple fabrication. With remarkable conversion efficiency and improved stability, PSCs exhibit high potential in scalable applications. However, concerns about the toxicity and leakage of lead from PSCs remain high, which are major factors limiting the application of PSCs. Given that Pb-induced effects are detrimental to the environment and human health, great efforts have been made to explore lead-free alternatives to PSCs, but the photovoltaic performance lags far behind that of the lead-based analogues. Consequently, effective elimination of Pb-leakage from the devices is crucial for future commercialization. In this review, we systematically discuss the hazards and potential threats of lead to the environment and biological species, followed by summarizing the advances in developing functional materials and effective techniques to prevent lead leakage. By reviewing both physical and chemical encapsulation, the correlation between molecular structures and lead-leakage prevention is analyzed, and the basic requirements and the working mechanism of efficient encapsulants are revealed. We also provide perspectives on the eco-friendly development of PSCs from different aspects.