Dual-Energy X-ray Imaging Enabled by Passivated Bilayer Copper-Based Halide Scintillators

Scintillators for X-ray imaging have gained significant interest due to their essential roles in medical diagnostics, security screening, and industrial inspection. However, conventional scintillators often suffer from limitations, such as a low light output efficiency or poor stability. Herein, we report a novel bilayer scintillator based on copper halide nanocrystals, comprising Cs3Cu2Cl5/Cs3Cu2I5 nanocrystals, which exhibits better performance in X-ray imaging. By optimization of the copper halide nanocrystal passivated with ammonium halides, the photoluminescence quantum yield can be increased from 41.85 to 66.18%, facilitating the performance of these bilayer copper-based halide scintillators. It utilizes energy-dependent attenuation contrast generated through differential X-ray absorption in the bilayer copper-based halide scintillators to generate dual-energy X-ray imaging. Moreover, the all-inorganic composition ensures the exceptional stability of the scintillator under prolonged X-ray irradiation. This study presents an innovative approach for developing next-generation, high-performance, and cost-effective X-ray imaging scintillators.