Metal Halide Perovskites for X-ray Imaging Scintillators and Detectors

Radiation detection, using materials to convert high-energy photons to low-energy photons (X-ray imaging) or electrical charges (X-ray detector), has become essential for a wide range of applications including medical diagnostic technologies, computed tomography, quality inspection and security, etc. Metal halide perovskite-based high-resolution scintillation-imaging screens or direct conversion detectors are promising candidates for such applications, because they have high absorption cross sections for Xrays due to their heavy atom (e.g., Pb2+, Bi3+, I-) compositions; moreover, these materials are solution-processable at low temperature, possessing tunable bandgaps, near-unity photoluminescence quantum yields, low trap density, high charge carrier mobility, and fast photoresponse. In this review, we explore and decipher the working mechanism of scintillators and direct conversion detectors as well as the key advantages of halide perovskites for both detection approaches. We further discuss the recent advancements in this promising research area, pointing out the remaining challenges and our perspective for future research directions toward perovskite-based X-ray applications.