Flexible, High Scintillation Yield Cu3Cu2I5 Film Made of Ball-Milled Powder for High Spatial Resolution X-Ray Imaging

Cu halide materials with low electronic dimension show great scintillation properties with high photoluminescence quantum yield (PLQY) and large Stokes shift, which can result in reabsorption-free scintillators. However, there is still a need for a large-scalable method to fabricate large amount of scintillation powder and large-size scintillation films. In this regard, a high scintillation yield Cu3Cu2I5-PDMS flexible film utilizing ball-milled Cu3Cu2I5 powder is developed. The ball-milled Cu3Cu2I5 powder shows a high PLQY of 74.5%, narrow emission peak of 80 nm and good ambient stability, demonstrating the potential of ball-milling method for large-scale scintillator production. Furthermore, the Cu3Cu2I5-PDMS film shows even high PLQY exceeding 90%, which may be ascribed to the passivation effect of PDMS resulting in a little longer carrier lifetime. The flexible Cu3Cu2I5-PDMS film can further deliver high spatial resolution of 6.8 lp mm(-1)@0.2 MTF in X-ray imaging and good stability under steady X-ray illumination. This work demonstrates that the ball-milling method could be an effective approach for large-scale fabrication of low electronic dimensional scintillation materials.