(PEA)2(FA)Pb2I7/PVDF Composite Flexible Films Enable Self-Powered X-ray Detection with High Sensitivity and a Low Detection Limit

Abstract Metal halide perovskites (MHPs) have attracted significant interest in the field of X-ray detection due to their unique semiconducting properties. However, the self-powered detection capabilities of almost all of these materials rely on their inherent ferroelectricity or heterojunction structures, yet the structure design and fabrication still pose significant challenges. By incorporating a polymer into a centrosymmetric MHP, we successfully prepared (PEA)2(FA)Pb2I7/PVDF composite flexible films (PEA = β-phenylethylamine, FA = formamidine, PVDF = poly(vinylidene fluoride)) and obtained self-powered X-ray responses in a nonpolar perovskite. Notably, the photodetector based on thin films exhibits excellent self-powered X-ray detection performance with a high sensitivity (559.11 μC Gyair–1 cm–2), a low detection limit (29.09 nGyair s–1), and excellent radiation stability. Our work offers a new strategy for self-driven devices without relying on ferroelectricity or heterojunctions, expanding halide perovskites in flexible film applications.