Hybrid perovskite X-ray detectors with enhanced radioluminescence via thermally activated delayed fluorescence

Abstract

Recently, metal halide perovskites have received great attention for detecting ionizing radiation. Perovskite-based photodetectors and scintillators have been successfully implemented for X-ray and γ-ray detection due to their high attenuation coefficient and excellent optoelectronic properties. However, relatively thick absorbing layers are required for the complete absorption of X-ray photons, which are very challenging to fabricate with solution processes. In this work, we designed hybrid devices coupled with excellent perovskite photodiodes to utilize the incident X-rays fully. Considering the heavy reabsorption of the perovskite layers, we blended CsPbBr3 with a Cu(I)-containing thermally activated delayed fluorescent complex (MAC*)Cu(Cz) to achieve down-conversion luminescence effectively to maximize the radioluminescence quantum efficiency, and we also found a faster afterglow compared with the commercial scintillators. Furthermore, we systematically investigated the performance metrics of the CsPbIBr2 photodiodes and scintillator films. The hybrid devices demonstrated significantly improved X-rays sensitivity, indicating potential for X-ray detection and imaging.