Radiation effects on the performance of flexible perovskite solar cells for space applications

Solar cells for space applications are required to be tolerant to harsh environmental conditions. Especially, tolerance against radiation and charged particles is mandatory. Here we study the effect of low-energy (<<1 MeV) proton radiation to evaluate the radiation tolerance of flexible perovskite solar cells (PSCs). Low-energy protons are more likely to be stopped in the shallower regions of solar cells, thereby causing greater performance degradation than high-energy protons. Flexible PSCs with layer sequence PET/ITO/PEDOT:PSS/perovskite/PCBM/BCP/metal were fabricated and were irradiated with 100 keV protons (fluence from similar to 3x10(10) to similar to 3x10(12) protons/cm(2), equating several years in space). Flexible PSCs exhibited a good radiation tolerance and did not show color center formation, revealing their outstanding resistance against low-energy proton radiation. This can be credited to the combined effect of intrinsically large carrier diffusion length exceeding the thin absorber film thickness and the defect tolerance of perovskite crystals.