Figure 3: Performance characterizations of the perovskite devices.

(a) J–V curves of perovskite solar cells based on different fullerene ETLs. CLCS, crosslinked C60-SAM; N-CLCS, non-crosslinked C60-SAM; 5D-CLCS, 5 wt.% MAI-doped crosslinked C60-SAM; 10D-CLCS, 10 wt.% MAI-doped crosslinked C60-SAM; 20D-CLCS, 20 wt.% MAI-doped crosslinked C60-SAM. (b) J–V curves with different sweeping directions and sweeping rates (hollow triangles and solid triangles represent the scanning direction from negative to positive bias and from positive to negative bias, respectively). (c) EQE (the integrated current density is 22.2 mA cm−2) and (d) steady-state photocurrent and efficiency at the maximum power point (0.93 V) of the optimized perovskite device with 10D-CLCS ETL. Statistics of the fill factor (FF) (e) and power conversion efficiency (PCE). (f) Distribution for devices with CLCS (35 samples) and 10D-CLCS ETLs (40 samples). (g) Comparison of the I–V characteristics of N-CLCS, CLCS and 5D-CLCS, 10D-CLCS and 20D-CLCS films deposited on normal glass substrates obtained by four-probe conductivity measurement. (h) J–V curves of perovskite device fabricated with PCBM and MAI-doped PCBM with different doping levels.