Toward Stable and Efficient Sn-containing Perovskite Solar Cells

Abstract Astonishing progress on the stability and performance of lead halide perovskite solar cells (PSCs) has been achieved in the past few years. However, the presence of toxic lead in the perovskite composition still remains a major challenge for the large-scale deployment due to legislation and environment issues. A straightforward solution is to develop lead-free perovskite alternatives without sacrificing the excellent optical and electrical properties. Among all the lead-free alternatives, non-toxic Sn halide perovskites are the most promising since Sn has similar ionic radius to Pb. Sn-based perovskites display optical and electronic properties similar to their lead analogues, which offers high potential for them to achieve high performance. However, the instabilities of Sn perovskites could hinder their development in terms of both performance and long-term stability. In this Perspective, recent advances and insights into the crystallization regulation, defect passivation, dimensionality reduction, and composition engineering are summarized and future prospects for stable and efficient Sn-based perovskite solar cells are discussed and outlined.