Polymer Composites Entrapped Ce-Doped LiYF₄ Microcrystals for High-Sensitivity X-ray Scintillation and Imaging

Scintillators are widely used for radiation detection. The ability of converting ionizing radiation into visible photons is critical for application in X-ray security, computed tomography, and nuclear cameras. Conventional scintillators involve a high-temperature preparation and pose challenges for device integration and processability. Here, we report a facile hydrothermal synthesis of Ce-doped LiYF₄ microcrystals (MCs) and their polymer composites for high-sensitivity X-ray detection and imaging application. These MC scintillators exhibit strong X-ray radioluminescence (RL) at ultraviolet wavelengths and show a high sensitivity to X-rays. Scintillating bulks based on these MCs display both strong RL and tunable emission across the visible spectrum. Further, these MC scintillators can be readily spun into a uniform film with a suitable MC content for X-ray imaging. Scintillating films can generate a strong X-ray-induced emission and long-term stability under X-ray illumination. Dose dependence of the RL intensity of our scintillating film indicates a high sensitivity to X-rays. Importantly, we exhibit an archetype application of scintillating films as X-ray radiography for a printed circuit board (PCB). Such an archetype can provide a decent spatial resolution as high as 0.54 mm. Our finding manifests MC composites of steady and efficient RL as a promising approach for X-ray radiography application.