Recently, the Institute of Solid State Physics of the Chinese Academy of Sciences Hefei Institute of Material Sciences has made progress in perovskite X-ray detection and imaging research. Researchers have proposed a new approach called "heterojunction strategy", which involves doping heterojunction CsPb2Br5 perovskite into the CsPbBr3 bulk phase to construct an electron (hole) fast channel and achieve high-speed transport of bulk carriers. Integration with thin film transistor (TFT) plates enables X-ray imaging.
Compared to traditional α- Compared with detector materials such as Se, CsI, and CdZnTe, metal halide perovskites have shown broad application prospects in medical imaging, non-destructive testing, and safety inspections due to their high sensitivity, low detection limit, and excellent spatial resolution. Especially inorganic perovskite CsPbBr3 stands out among numerous perovskite materials due to its excellent environmental stability and high-temperature plasticity. However, CsPbBr3 is usually reported in single crystal form, which is difficult to prepare and costly. CsPbBr3 devices prepared in polycrystalline form exhibit low bulk carrier mobility, which limits their application in array imaging.
"Heterogeneous hinge strategy" hinges the second phase of 2D CsPb2Br5 in the grain boundaries of CsPbBr3. The introduction of 2D CsPb2Br5 does not lead to a decrease in the current baseline, but instead increases the carrier mobility within CsPbBr3. 2D CsPb2Br5 establishes electron (hole) acceleration channels at the grain boundaries of CsPbBr3. Under X-ray irradiation, 2.58 × 105 is achieved by applying a low voltage of 25 V μ The high sensitivity of C Gyair cm-2 has a minimum detection limit of 127.9 nGyair s-1 at a voltage of 0.5 V, achieving a high spatial resolution of 1.57 lp mm-1. Furthermore, researchers integrated polycrystalline CsPb2Br5/CsPbBr3 on the TFT backplane to achieve multi pixel X-ray array imaging. This work not only demonstrates the feasibility of CsPbBr3 material in imaging applications, but also opens up new material systems and design ideas for the application of perovskite in X-ray imaging technology.
The relevant results were published in Advanced Functional Materials. The research work has received support from the National Natural Science Foundation of China and the Dean's Fund of Hefei Research Institute.
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