How Soft Metal Halide Perovskite Lattices Heal Following Energetic Particle Bombardment

Abstract

Recent NASA tests have demonstrated the exceptional durability of metal halide perovskite solar cells against space radiation; however, the atomic-level mechanisms governing this resilience remain speculative. Here, we elucidate the self-healing capacity of CsPbI³ under energetic particle bombardment (1 eV to 1000 eV) using large-scale Molecular Dynamics (MD) simulations and a ReaxFF reactive force field. To analyze the resulting massive trajectory datasets, we employ a novel relational database (SQL) framework that enables scalable, query-based interrogation of defect dynamics. Our analysis reveals that the material's radiation hardness arises from the intrinsic softness of the perovskite lattice, specifically the ability of PbI⁶ octahedra to dissipate energy through collective tilting and spinning. We observe a strong species-dependent recovery mechanism where ≈32% of displaced halides return to lattice sites within 10 ps, effectively preventing permanent amorphization. Furthermore, we demonstrate that radiation-induced structural disorder correlates quantitatively with classical Glazer tilt systems and matches octahedral distortions observed in experimental nanocrystals. These results explain the material’s proven spaceflight performance and establish a powerful computational workflow for analyzing defect tolerance in soft semiconductors.