Halide perovskite x-ray detectors: Fundamentals, progress, and outlook

Halide perovskites have demonstrated great potential in x-ray detectors, due to their high x-ray attenuation coefficient, large bulk resistance, ultralong carrier diffusion length, and adjustable bandgap. Moreover, their abundant raw materials and simple processing combined with excellent compatibility with integrated circuits make them ideal for cost-efficient and high-efficiency real-world imaging applications. Herein, we comprehensively reviewed advances and progress in x-ray detection devices based on halide perovskites. We expound on the fundamental mechanisms of interactions between x rays and matter as background and indicate different parameters for different types of x-ray detectors, which guides the basic requirements on how to select and design suitable materials for active layers. After emphasizing the superb properties of halide perovskites through the shortcomings of commercial materials, we evaluate the latest advancements and ongoing progress in halide perovskites with different dimensions and structures for both direct and indirect x-ray detectors, and discuss the effect of dimensional varieties on the device performance. We also highlight current challenges in the area of perovskite x-ray detectors and propose corresponding solutions to optimize halide perovskites and optimize x-ray detectors for next-generation imaging applications.