High-Rate Spectrally Resolved X-ray Photon Counting with CsPbBr ₃ Single-Crystal Perovskite Detectors

Conventional energy-integrating X-ray detectors do not resolve the energies of individual photons and therefore offer limited material discrimination. Here, we report CsPbBr 3 single-crystal perovskite detectors for spectrally resolved X-ray photon counting. CsPbBr 3 detectors resolve the K-edge features in transmitted X-ray spectra of indium, barium, and lead. Compared with our previous work, the improved crystal quality and device fabrication enable CsPbBr 3 detectors to sustain electric fields up to about 13 kV cm –1 and achieve incident photon count rates of about 230 and 420 kcps pixel –1 at 10 and 30% dead-time loss, respectively.Under these conditions, they also achieve energy resolutions of about 5.2% at 59.5 keV ( 241 Am) and 2.9% at 122 keV ( 57 Co). These results indicate that the low-cost CsPbBr 3 is promising for high-rate, spectrally resolved X-ray photon counting.