Fig. 4

Influence of Cd²⁺ ions on the carrier concentration and tDOSs. a Capacitance–voltage curves of NBG PSCs with and without Cd²⁺ ions at 295 K. b ln(T²/ω) vs 1/T curve for determining the trap depth and attempt-to-escape angular frequency. c tDOS studies of NBG PSCs with and without Cd²⁺ ions at 295 K. d and e TRMC measurement for electron carrier property with a structure of quartz/PEDOT:PSS/NBG perovskite films without (d) and with (e) Cd²⁺ ions. The intensities are normalized to the highest peak intensity. f V_OC evolution with light intensity of NBG PSCs with and without Cd²⁺ ions. All studies in Fig. 4 are based on 1000-nm-thick perovskite film. Source data are provided as a Source Data file