Recent progress toward highly efficient tin‐based perovskite (ASnX3) solar cells

Abstract Recently, lead halide perovskites have attracted great attention in photovoltaic field because of high power conversion efficiency. However, the toxicity of lead in perovskite can result in environment issues, which are the major challenge for commercial application. In this context, environmentally friendly lead‐free perovskite alternatives are highly desired. Bearing excellent photophysical and electronic properties, tin‐perovskites (ASnX 3 ) are the most promising alternative. In reality, extensive efforts have been committed to the development of Sn‐based perovskite solar cells. In this review, we summarized the theoretical fundamentals of Sn‐based perovskites, including lattice, phases, molecular orbital, redox property, and defects. Then varieties of tactics to improve devices performance were detailed reviewed. Finally, perspectives on further research directions in improving Sn‐based solar cells performance are presented.