Unveiling fast neutron induced degradation mechanisms in perovskite solar cells

Abstract

Metal halide perovskite solar cells (PSCs) offer high power-to-weight ratios and superior absorption properties, holding significant promise for space and avionics applications. However, the irradiation stability of PSCs, particularly under fast neutron exposure, remains insufficient. Here, we report a comprehensive study of the degradation mechanism of perovskite devices under fast neutron irradiation and propose an effective shielding strategy. We identified the decomposition of organic cations and subsequent degradation of neutron-irradiated perovskite films, both of which were found to be irreversible over extended periods. Based on this understanding, we fabricated a boron-containing transparent substrate that enabled the stability of PSCs under a fluence of 8.67 × 107 n cm−2, equivalent to approximately 5 years of fast neutron exposure in the International Space Station environment. Further characterizations revealed that this strategy reduced defect density, alleviated lattice distortion, and suppressed non-radiative recombination. This work provides a new substrate-engineering strategy for enhancing the irradiation stability of photovoltaic devices without compromising the intrinsic properties of perovskite film.