Fig. 5: Operational stability test of CsPbI3 solar cells.

PCE tracking of the cells operating a under normal and b 10× concentrated AM 1.5 G illumination in ambient conditions. c 2000 h PCE tracking of the cells continuously operating under light illumination (initial cell current density 20 mA cm-2) and bias voltage (0.95 V) in N2 atmosphere. d Low (-20 °C) ~ high (60 °C) temperature cycling test in N2 atmosphere for 100 cycles.