Enhancement of CsPbBr ₃ Perovskite Solar Cells Through EABr Modification

Recently, inorganic CsPbBr 3 perovskite solar cells (PSCs) have attracted significant research interest due to their high power conversion efficiency (PCE) and remarkable stability in humid environments. Despite these advantages, the fabrication of high-quality CsPbBr 3 perovskite via traditional solution-processing methods remains challenging, primarily due to the limited solubility of CsBr in conventional solvents. Therefore, a simplified EABr-assisted two-step spin-coating approach was developed to fabricate CsPbBr 3 perovskite films with high phase purity, excellent crystallinity and large grains under ambient atmosphere conditions. In the first spin-coating step, EABr is incorporated into the PbBr 2 layer, improving its wettability and creating space for the growth of large perovskite crystals. In the subsequent spin-coating process, the use of a green high-concentration CsBr/H 2 O solution enables efficient deposition of sufficient CsBr in a single-step operation. By precisely optimizing the EABr content, compact CsPbBr 3 perovskite films with smooth surfaces, large grain sizes, high phase purity and excellent crystallinity were successfully fabricated. Test results demonstrated that the efficiency of the FTO/SnO 2 /CsPbBr 3 /Carbon structure PSCs achieved a notable value of 7.32%. Moreover, the unpackaged device retained over 90% of its initial efficiency after 45 days of storage under standard ambient conditions.