Proton Beam and Solar Light Irradiation Effects in Multiple-cation Halide Perovskites – H+BOOST

Halide perovskites including hybrid organic-inorganic perovskites (HOIPs) have revolutionized the field of optoelectronics due to their promising device-related properties that include high absorption coefficients, high charge-carrier mobilities and low exciton binding energy values relevant for photovoltaics, light-emitting diodes, and photodetectors. While the device applications of perovskite thin films have been extensively investigated in the recent years, unambiguous understanding on the influence of external stimulants such as temperature, humidity and high-energy radiation remains elusive.
Since both intrinsic and extrinsic effects can influence the photophysical properties of perovskite materials, detailed understanding of external stimuli such as radiation effects is crucial for further optimization of solar cell devices. This German-French consortium will investigate fundamental aspects of improving the stability of perovskite materials by increasing their defect-tolerance through proton (H+) irradiation. The scientific objectives of the H+BOOST project will target compositionally engineered multiple-cation HOIPs that will be hardened towards atomic level defects by high-energy proton irradiation treatments. The central goal is to demonstrate whether a post-synthesis processing of perovskite solar cells with ~1 MeV proton irradiation can be applied to different HOIPs PV device architectures and adapted to other HOIPs composition for enhancing their environmental and operational stability. Moreover, the compositionally engineered quadruple-cation lead perovskites will be systematically investigated towards the role of intrinsic point defects induced via ~1 MeV proton irradiation to clarify defect-assisted processes relevant to PV stability and durability during ageing. This project combines the complimentary expertise of the German research group in chemical engineering of defined HOIP single crystals and thin films as well as their integration in solar cell devices with the expertise of the French partners in proton irradiation and spatially resolved microscopy and spectroscopy to correlate defect formation with solar cell performance.