Direct X-ray Detectors Based on an Eco-Friendly Semiconducting Zero-Dimensional Organic Zinc Bromide Hybrid

Direct X-ray detectors that convert X-rays to electrical charges have broad applications in medicine and security screening. Common semiconductors like silicon and selenium for direct X-ray detectors have limitations in performance, versatility, and cost-effectiveness. Among new materials under investigation, metal halide perovskites demonstrate great potential for X-ray detectors; however, they are limited by low stability and toxicity. Here, we report, for the first time, a stable and eco-friendly zero-dimensional (0D) organic metal halide hybrid (OMHH), (TPA-P)₂ZnBr₄, for efficient X-ray detectors. With molecular sensitization, wherein metal halides (ZnBr₄^2-) act as X-ray absorbers and organic semiconducting components (TPA-P⁺, 4-(4-(diphenylamino)phenyl)-1-propylpyridin-1-ium) as charge transporters, 0D (TPA-P)₂ZnBr₄ detectors exhibit an impressive sensitivity of 2,292 μC Gy_air^-1 cm^-2 at 20 V and a low detection limit of 37.5 nGy_air s^-1. The exceptional stability of 0D (TPA-P)₂ZnBr₄ facilitates remarkably stable direct X-ray detection and shows the tremendous potential of rationally designed 0D OMHHs as new-generation radiation detection materials.