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X-ray detectors based on scintillators are widely used in the fields of medical imaging, high-energy physics, geological exploration, and industrial detection. The development of scintillation materials with different characteristics has become the focus of considerable research interest. Herein, we report a facile hydrothermal synthesis of Gd- and Eu-codoped LiLuF4 microcrystals (MCs), which exhibit strong luminescence of Eu3+ ion characteristic emission, characterized by distinct red fluorescence emission. The research shows that Gd3+ co-doping effectively improved the sensitivity and light yield of LiLuF4:Eu MCs by regulating the proportion of co-doping ions. In addition, the detection limit is 140.72 nGy s−1 for LiLuF4:Eu,Gd MCs, approximately 39 times lower than the dose requirement of medical diagnosis. Based on LiLuF4:Eu,Gd MCs with the superior scintillation properties, a MC-composited film with 250 μm thickness was prepared by a direct coating method. The uniform and high-loading scintillation film exhibits outstanding imaging performance with a high spatial resolution of 14.8 LP mm−1, which confirms the application potential of X-ray imaging. [ABSTRACT FROM AUTHOR]

In recent years, the development of new scintillation materials with red and near-infrared light emission has had significant advantages based on the development of an avalanche photodiode with high quantum yield. This study used a hydrothermal method to synthesize rare-earth-doped Cs2NaScCl6 crystals, in which a red emission of Cs2NaScCl6:Sm was investigated with high X-ray sensitivity and low detection limit. In addition, a tunable wavelength range of radioluminescence can be achieved, in which a near-white light emission can be generated by precisely controlling the proportion of Sm3+ and Tb3+ doping concentrations. Meanwhile, a Cs2NaScCl6:7%Sm scintillation film has been successfully prepared by direct coating with a thickness of 150 μm, which achieves a spatial resolution of 11.9 lp mm−1 based on X-ray imaging experiments. Therefore, this perovskite material has shown potential application as an eco-friendly multifunctional imaging material. [ABSTRACT FROM AUTHOR]

The current development direction of magneto-optical (MO) isolators involving miniaturisation and application in high-power lasers encounters difficulties in material application because preparing materials with excellent optical quality and a high Verdet constant remains a challenge. Herein, (Tb1−xCex)3Sc2Al3O12 (x = 0.001, 0.0025, 0.005, 0.01, 0.015, 0.02) MO ceramics with different doping concentrations were prepared by vacuum sintering. The phase structure, element distribution, microstructure, relative density, optical properties, surface properties and MO properties of the (Tb1−xCex)3Sc2Al3O12 ceramics were also characterised. Experimental characterisation reveals that the (Tb1−xCex)3Sc2Al3O12 ceramics have a pure Tb3Sc2Al3O12 (TSAG) phase and exhibit an excellent uniform element distribution. In addition, no secondary phase was detected in FESEM images with the increase in Ce concentration. However, a few small-sized residual pores, which remain entrapped in the Ce0.015TSAG and Ce0.02TSAG ceramics, can be observed. Moreover, all the obtained ceramics have good optical quality, and the in-line transmittances of the (Tb1−xCex)3Sc2Al3O12 ceramics at 1064 nm are 81.7%, 83.7%, 80.0%, 84.0%, 68.8% and 77.7%. The Verdet constant of the ceramics is optimised by Ce doping, and the Verdet constants of all the ceramics at the test wavelength are better than those of TSAG ceramic. The Verdet constant of the Ce0.01TSAG ceramic is still superior to that of the TSAG ceramic in the same temperature range. Finally, the extinction ratio values for the CexTSAG (x = 0.001, 0.0025, 0.005, 0.01) ceramics exceeded 40 dB. The Ce0.01TSAG ceramic shows the best optical transmittance, the highest magneto-optical FoM values and the highest Verdet constants. Thus, this ceramic can be used for a high-power laser in the visible and near-infrared regions in the future. [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]