fig6

Figure 6. Preparation process, device performance and structure diagram of graded perovskite homojunction. (A) Schematic illustration of the fabrication process of mixed Pb/Sn, Pb‐based and graded Pb/Sn for graded perovskite homojunction. Reproduced with permission from Sun et al.^[49]. (B) Preparation process and material structure model of perovskite. (C) Schematic band diagram of perovskite films and quadruple-cation PSCs. (D) Performance of cells with 2% PMAI and without PMAI. Reproduced with permission from Xiang et al.^[50]. (E) Graded band alignment homojunction structure in solar cells. Reproduced with permission from Yuan et al.^[51]. CBM: Conduction band minimum; VBM: valence band maximum.