Inorganic CsPbIBr₂-Based Perovskite Solar Cells: Fabrication Technique Modification and Efficiency Improvement

CsPbIBr₂ photovoltaic materials attract remarkable attention in the field of all-inorganic halide perovskite solar cells (HPSCs) due to their superior humidity stability and heat endurance. Since the first report in 2016, the power conversion efficiency (PCE) of CsPbIBr₂-based HPSCs (Cs-HPSCs) has increased from 4.7% to 11.53% with an almost 2.5-fold leap in a short time. Cs-HPSCs have also become one of the most researched materials in the all-inorganic perovskite family. Here, the crystal structure and spectrum properties of CsPbIBr₂ are first elucidated to provide a preliminary overview. Subsequently, significantly modified strategies, including various assisting procedures for spin coating, interface engineering, and element impurity doping for superior perovskites and better-performing cells are meticulously introduced. Overall, the development process of the CsPbIBr₂ materials is focused on, and the feasible strategies to improve fabrication techniques for superior perovskite films and corresponding device PCEs are emphatically summarized, with the aim to provide some constructive guidelines for the rapid development of Cs-HPSCs.