Proton irradiation effects on mechanochemically synthesized and flash-evaporated hybrid organic-inorganic lead halide perovskites

A hybrid organic-inorganic halide perovskite is a promising material for developing efficient solar cell devices, with potential applications in space science. In this study, we synthesized methylammonium lead iodide (MAPbI3) perovskites via two methods: mechanochemical synthesis and flash evaporation. We irradiated these perovskites with highly energetic 10-MeV proton-beam doses of 1011, 1012, 1013, and 4 × 1013 protons/cm2 and examined the proton irradiation effects on the physical properties of MAPbI3 perovskites. The physical properties of the mechanochemically synthesized MAPbI3 perovskites were not considerably affected after proton irradiation. However, the flash-evaporated MAPbI3 perovskites showed a new peak in X-ray diffraction and an increased fluorescence lifetime in time-resolved photoluminescence under high-dose conditions, indicating considerable changes in their physical properties. This difference in behavior between MAPbI3 perovskites synthesized via the abovementioned two methods may be attributed to differences in radiation hardness associated with the bonding strength of the constituents, particularly Pb–I bonds. Our study will help to understand the radiation effect of proton beams on organometallic halide perovskite materials.