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MOFs have good potential for X-ray detection, but direct X-ray detection in single crystal form is rarely reported. In this work, we successfully synthesized Pb-TCPE, and the single crystal achieves a low detection limit and high detection sensitivity of 4812.6 μC Gyair−1 cm−2, which exhibits great potential for X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

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. Here we report that Ce‐doping can increase sensitivity in lead‐free double perovskite crystals (Cs2NaTbCl6) for X‐ray detection and imaging. The introduction of Ce ions as sensitizer can be used to improve the radioluminescence of the crystals. The light output of Ce : Cs2NaTbCl6 crystals is about 52153 ph/MeV, which is 25 % higher than that of un‐doped crystal. The X‐ray sensitivity is significantly enhanced. Based on our scintillation film X‐ray detector the detection limit is 30 nGy ⋅ s−1, which is about 1/183 of the typical medical imaging dose. Our scintillating film has excellent imaging ability with spatial resolution of up to 10 lp/mm. This research shows that Ce : Cs2NaTbCl6 perovskite crystal scintillators are promising materials for X‐ray imaging application. [ABSTRACT FROM AUTHOR]

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(IO3)3 single crystal grown through low‐cost solution processing is reported with a wide bandgap of 4.1 eV and a large atomic number of 53.2. The roles of IO and TmO groups for charge transport in the Tm(IO3)3 are revealed with the structural difference between the [101] and [1¯01]$[{\bar{1}}01]$ crystal orientations. Based on anisotropic responses of material properties and detection performances, it is found that the [1¯01${\bar{1}}01$] orientation, the path with fewer IO groups, achieves a high resistivity of 1.02 × 1011 Ω cm. Consequently, a single‐crystal detector exhibits a low dark current and small baseline drifting due to the wide bandgap, high resistivity and less ion migration of Tm(IO3)3, resulting in a low detection limit of 85.2 nGyair s−1. An excellent X‐ray imaging performance with a high sensitivity of 4406.6 µC Gyair−1 cm−2 is also shown in the Tm(IO3)3 device. These findings provide a new material design perspective for high‐performance X‐ray imaging applications. [ABSTRACT FROM AUTHOR]

Scintillators can convert high-energy rays into ultraviolet or visible light and are widely used in medical diagnosis, safety inspection, and industrial flaw detection. Nowadays, conventional scintillation materials have certain limitations, including the extreme synthesis conditions and complex synthesis process of bulk scintillators, as well as toxicity and poor stability of perovskite quantum dots (QDs). Fluoride has high stability and simple synthesis, which can effectively solve these problems. LiYbF4 has the advantages of a larger atomic number and density, and the synthesis of LiYbF4:Tb nanocrystals (NCs) exhibited good stability to thermal injection. X-ray tests showed that Tb3+-doped LiYbF4 NCs were more sensitive to X-rays than the commercial scintillator BGO, and the detection limit was 360 nGy s−1, which was 1/15 of the medical X-ray detection dose rate. Our self-made scintillation film with a load of 40 wt% and a thickness of 150 μm had excellent X-ray imaging capabilities with a spatial resolution of up to 20 LP mm−1 (MTF = 0.35), which shows great application potential in the X-ray imaging of biological and non-biological structures. [ABSTRACT FROM AUTHOR]