Publications by authors named "Xieming Xu"

Article Synopsis
  • - The study introduces layered hybrid double perovskites (LHDPs) as promising candidates for X-ray detection, overcoming sensitivity limitations by enhancing charge transport through a novel structural design using ethylenediamine (EDA).
  • - The new LHDPs, (EDABr)4AgBiBr8 and (EDABr)4CuBiBr8, feature a unique Ruddlesden-Popper-like interlayer structure that improves interlayer interactions and charge transport due to a dual-ion-woven supramolecular framework.
  • - The developed devices show exceptional sensitivity (5250 μC Gyair-1cm-2), a low detection limit (91 nGyair s-1), and impressive radiation
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Scintillation materials have been widely used in various fields, such as medical diagnosis and industrial detection. Chalcogenides have the potential to become a new generation of high-performance scintillation materials due to their high effective atomic number and good resistance to radiation damage. However, research on their application in radiation detection is currently very scarce.

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The strategy of introducing large organic cations into three-dimensional perovskites could reduce the dimensionality of perovskites to form quasi-two-dimensional (quasi-2D) perovskites, resulting in increased stability and reduced detection limits due to less ion migration. Herein, a quasi-2D perovskite single crystal (BDA)(MA)PbBr (BDA = NHCHNH, MA = CHNH) with a layered structure was grown by the temperature-cooling solution method. The X-ray detector based on the (BDA)(MA)PbBr single crystal has a sensitivity as high as 1984 μC Gy cm at 55.

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Semiconductor-based X-ray detectors with low detectable thresholds become critical in medical radiography applications. However, their performance is generally limited by intrinsic defects or unresolved issues of materials, and developing a novel scintillation semiconductor for low-dose X-ray detection is a highly urgent objective. Herein, a high-quality rare-earth iodate Tm(IO ) single crystal grown through low-cost solution processing is reported with a wide bandgap of 4.

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Materials exhibiting mechanoluminescence (ML) are a class of smart materials capable of mechanical-to-light energy conversion. Thus, ML materials have been widely used in various electronic applications such as smart sensors, security systems, human-machine interfaces, and energy harvesting systems. Herein, we report a centrosymmetric ML semiconductor host material family MGaS (M = Ca, Sr), which features in-layered structures constructed with unique distorted bi-tetrahedral [GaSS] lattice units.

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Radiographic screens are widely used in high energy physics, national defense, aviation, radiodynamic therapy and medical imaging due to their scintillation materials that can transform high-energy particles or rays into ultraviolet (UV) visible light or other signals. In recent years, lanthanide doped fluoride nanocrystals (NCs) have attracted much attention due to their excellent optical properties and stability. In this work, multiple lanthanide-doped LiLuF nanocrystal scintillation materials were synthesized by thermal decomposition.

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Scintillators are widely used for nondestructive testing, nuclear medicine imaging, space exploration and security inspection. Recently, lead halide perovskite scintillation crystals have been brought into focus due to their effective atomic number, fast scintillation decay time, strong luminous efficiency, and tunable band gap. However, their application is limited by lead toxicity.

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