Pure Tin Halide Perovskite Solar Cells: Focusing on Preparation and Strategies

Abstract

Metal halide perovskite solar cells (PSCs) have emerged as an important direction for photovoltaic research. Although the power conversion efficiency (PCE) of lead-based PSCs has reached 25.7%, still the toxicity of Pb remains one main obstacle for commercial adoption. Thus, to address this issue, Pb-free perovskites have been proposed. Among them, tin-based perovskites have emerged as promising candidates. Unfortunately, the fast oxidation of Sn2+ to Sn4+ leads to low stability and efficiency. Many strategies have been implemented to address these challenges in Sn-based PSCs. This work introduces stability and efficiency improvement strategies for pure Sn-based PSCs by optimization of the crystal structure, processing and interfaces as well as, implementation of low-dimension structures. Finally, new perspectives for further developing Sn-based PSCs are provided.