Performance Optimization of CsPb(I 1–x Br x) 3 Inorganic Perovskite Solar Cells with Gradient Bandgap. - Wang, Luning; Yang, Sui; Xi, Tingting; Yang, Qingchen; Yi, Jie; Li, Hongxing; Zhong, Jianxin (Energies (19961073), 2023)