fig2

Figure 2. (A) Illustration of the role of the ideal passivator at the interface between ETL and perovskite materials or between HTL and perovskite materials to change the CBM or VBM locations, respectively to further improve the V_OC. (B) The passivator Cs⁺ was used to fill the MA⁺ vacancy, leading to decreased VBM location of the perovskites and increased V_OC^[85]. Copyright 2022 Wiley. (C) The use of ACh⁺ passivators to fill the MA⁺ vacancy leads to removing the deep trap states, as evidenced by the DOS analysis^[85]. Copyright 2022 Wiley. (D) The use of ACh⁺ passivators to fill the MA⁺ vacancy leads to removing the shallow trap states, as evidenced by the DOS analysis^[87]. Copyright 2017 Wiley.