High-Quality MAPbCl₃ Polycrystalline Wafers for High-Performance Photodetectors and X-ray Detectors

Polycrystalline perovskite-type MAPbCl 3, which exhibits a low grain-boundary trap state and high carrier mobility, is believed to achieve the highest performance of perovskite-based photoelectric and X-ray detection devices. However, the correlation between the carrier transport properties of MAPbCl 3 polycrystalline wafers and their performance in photodetection and X-ray detection is still unclear. In this work, high-quality MAPbCl 3 polycrystalline wafers were prepared by the hot-pressing method, and their photoelectric and X-ray response performance were investigated. It is found that the MAPbCl 3 polycrystalline wafer photodetector exhibits a responsivity of 130 mA W – 1, an external quantum efficiency of 38%, and a specific detectivity of 3.35 × 10 11 Jones under a 15 V bias. Moreover, the X-ray detector demonstrates a sensitivity of 761.04 μC Gy air –1 cm –2 at a 15 V bias, significantly surpassing the performance of commercial amorphous selenium detectors (20 μC Gy air –1 cm –2 ). The reason may be that reduced intergranular defects in MAPbCl 3 polycrystals enhance the efficient generation of photogenerated electron–hole pairs and lower the carrier recombination probability at grain boundaries. These findings highlight the promising application prospects of MAPbCl 3 polycrystalline wafers in photodetection and X-ray detection, providing research directions for the development of high-performance detectors.