Lead halide perovskite single crystals with a high X-ray stopping power and large μτ product have been successfully used for X-ray detection. However, poor air stability and ionic migration lead to the degradation of the devices for long-term operations. Here, we report a solution-processed lead 0D bulk Cs4PbI6 single crystal, which have I atoms in isolated [PbI6]4–. This 0D Cs4PbI6 single crystal has a μτ product of 9.7 × 10–4 cm2 V–1 and an activation energy of 321.28 meV. We have fabricated a photoconductor device with a symmetric Au/Cs4PbI6/Au sandwich structure, which exhibits a high sensitivity of 451.49 μC Gy–1 cm–2 under 30 keV X-ray irradiation at an applied voltage of 30 V. After storing the device in air at room temperature for three months, the device retains nearly the same sensitivity as the original. These results demonstrate that this 0D Cs4PbI6 perovskite single crystal has great potential for practical X-ray detection applications.
Halide perovskites have shown promising potential for direct X-ray detection due to their high X-ray absorption coefficient, low trap states and convenient fabrication process. However, it is still a challenge to achieve high sensitivity, low dark current and low detection limit in a single material. The deep reason for this is the trade-off between the material’s μτ product and resistivity. Here we report the construction of an organic–inorganic hybrid anti-perovskite ((2-Habch) 3 Cl(PtI 6 )) with indirect transition and low orbital symmetry at the band edge to achieve an ultralong intrinsic lifetime and thus break the trade-off. (2-Habch) 3 Cl(PtI 6 ) achieves an unprecedented long carrier lifetime of >3 ms, leading to a large μτ product of 6.25 × 10 −3 cm 2 V −1 and high resistivity of 10 12 Ω cm, outperforming most X-ray detection materials. These properties enabled the development of X-ray detectors that simultaneously achieve an ultralow dark current of 0.21 nA cm −2 , high sensitivity of 1.0 × 10 4 µC Gy air −1 cm −2 , ultralow detection limit of 2.4 nGy air s −1 and excellent operational stability with no observable baseline drift, outperforming state-of-the-art perovskite single-crystal detectors. The rare combination of high performance in almost every figure of merit in the anti-perovskite-based X-ray detector could enable new-generation X-ray detection systems.
危险品化学品经营许可证（带存储）