DOI: https://doi.org/10.29363/nanoge.pvspace.2022.015
Publication date: 8th June 2022
Perovskite solar cells (PSCs) can be fabricated as lightweight, flexible, and highly efficient power devices at low cost. This advantage matches their applications to spacecrafts. We have evaluated the resistance of PSCs to high energy radiations, which is the biggest deterioration factor of the solar cells in the space. PSCs exhibit high radiation tolerance after irradiating PSCs with 1 MeV electrons and 50 keV protons and perovskite crystals had a low minority-carrier diffusion length (DL) after irradiating perovskite layers with 1MeV electrons. It has been reported that the photocurrent-voltage (I-V) characteristics of InP solar cells, which have a low DL, recovers after radiation deterioration. To clarify whether or not that the perovskite crystals are introduced with defects by radiation, the I-V characteristics of PSC immediately after irradiation and time dependence have been evaluated. At room temperature, 8 MeV proton beam (an energy that can penetrate the PSC and cause deterioration to the all PSC layers) was irradiated to the PSC using high efficiency CsMAFAPb(IBr)3 perovskite and the I-V characteristics immediately after irradiation and its time dependence were evaluated. The energy incident on the PSC (<1 μm) after passing through the 0.3 mm thick quartz glass substrate on the surface was 4.4 MeV. We measured the remaining factor of the parameter of I-V characteristics (the short-circuit current (Isc), the open-circuit voltage (Voc) and fill factor (FF)) in PSCs as a function of proton beam fluence. Up to radiation dose of 1×1013 /cm2, no significant degradation was seen in all parameters. With a radiation dose of 1×1014 /cm2, no degradation of 5% or more was observed in the Isc while FF decreased by 24% and Voc decreased by 9% immediately after irradiation and they recovered to 6% and 3%, respectively, 3 min. after irradiation. We consider that the deterioration and recovery of I-V characteristics observed in 1×1014 /cm2 was due to the deterioration and recovery of the charge transport layers. From the results of I-V characteristics immediately after 8 MeV proton irradiation, it was clarified that no defects were introduced into the perovskite crystals to deteriorate power generation performance with a radiation dose of 1×1014 /cm2. These investigations corroborate high radiation tolerance of the hybrid perovskite semiconductor.