Defect Dynamics in Proton Irradiated CH₃NH₃PbI₃ Perovskite Solar Cells

Perovskite solar cells have been shown to be of extraordinary radiation hardness, considering high energetic (68 MeV) proton irradiation with doses up to 10 13 p cm −2 . In this study electrical and photoelectrical properties of perovskite solar cells with and without proton irradiation are analyzed in detail. The results reveal that proton irradiation improves the open circuit voltage, fill factor, and recombination lifetime of photogenerated charge carriers in perovskite solar cells. These enhancements are mainly a result of the lower nonradiative recombination losses in the proton irradiated devices. The proton treatment creates shallow traps, which may be associated with the proton induced point defects due to the displacements of atoms in the inorganic Pb–I framework, which act as unintentional doping sources and partially compensate deep traps originated from the photodegradation of methylammonium molecules.