Bismuth-Doped Cesium Zirconium Chloride Microcrystal Scintillators for X-ray Computed Tomography Imaging

Metal halides have shown potential as scintillators for X-ray detection due to their high light yield and ease of synthesis. However, the poor X-ray absorption of these halides has hindered their practical application. Herein, Bi3+ ions are introduced into Cs2ZrCl6 (CZC) microcrystals by a simple solution method in order to improve the absorption of X-rays. The energy level transitions of Bi3+ ions enhanced the photoluminescence and increased the atomic number for better X-ray absorption, with a detection limit of 469 nGyair/s. An X-ray detection system was designed based on the Cs2ZrCl6:Bi3+ (CZCB) scintillator, and clear projection images were obtained with a spatial resolution of 15.9 lp/mm. Moreover, the 3D visualization computed tomography (CT) image of a ballpoint pen was successfully reconstructed. All of the results demonstrate that the CZCB microcrystals constitute a new generation of potential scintillators that can be used in X-ray CT imaging.