Fig. 4. Performance of Cs₃Bi₂I₉ PSC photodetector.

a Dark I–V curve of the Cs₃Bi₂I₉ PSC photodetector with the right-hand inset showing dark current statistics for different devices measured at 10 V bias and the left-hand one device configuration. b I–V curves of the Cs₃Bi₂I₉ PSC photodetector measured in the dark and with illumination at intensity from 9.2 × 10⁻⁶ to 300.1 mW cm⁻², λ = 462 nm. c Light-intensity-dependent responsivity and d external quantum efficiency of the Cs₃Bi₂I₉ PSC photodetector measured at various biases. e Measured dark-current noise of the Cs₃Bi₂I₉ PSC photodetector at 4 V bias. f Detectivity of the Cs₃Bi₂I₉ PSC photodetector measured at various biases.