Isopropanol-modulated ethyl acetate green antisolvent for enhancing the performance of CsPbBr3 perovskite solar cells

CsPbBr 3 perovskite solar cells (PSCs) have attracted increasing attention due to their superior thermal and environmental stability; however, their power conversion efficiency (PCE) remains limited by uncontrolled crystallization and high defect density during solution processing. Meanwhile, the widespread use of toxic antisolvents and the limited effectiveness of single control strategies necessitate the development of greener and more effective fabrication methods. To address these issues, this study introduces a green mixed antisolvent by incorporating isopropanol (IPA) into ethyl acetate (EA), coupled with a three-step spin-coating process for the deposition of CsPbBr 3 films. By adjusting the volume fraction of IPA in the mixed antisolvent, the crystallization of CsPbBr 3 films was effectively regulated, resulting in dense, uniform films with low defect density. At an optimal IPA volume fraction of 10%, dense and hole-free CsPbBr 3 films were obtained with markedly suppressed non-radiative recombination. As a result, the corresponding CsPbBr 3 PSCs exhibited a significantly enhanced PCE of 8.15%, compared with 5.63% for devices processed using pure EA. Moreover, the optimized device retained 97.9% of its initial efficiency after 30 days of storage under ambient conditions without encapsulation. This work provides a practical solution for fabricating effective and environmentally friendly inorganic perovskite photovoltaic devices.