Composition Modulation of Cs2ZrCl6-based Scintillator Film via Vapor Deposition for Large-Area X-Ray Imaging.

Abstract

Metal halide scintillators for X-ray imaging have shown remarkable potential, however, achieving large-area film has been hindered by challenges in materials design and fabrication methods, particularly regarding composition uniformity for high-resolution imaging applications. Here, a multi-source vapor deposition (MSVD) method is employed to realize the facile composition modulation by designing MA⁺ and Br^- (MA⁺ = methylammonium) co-doped Cs₂ZrCl₆ (MCZCB) and further synthesizing a uniform and large-area scintillator film. The incorporation of MA⁺ and Br^- ions, with their slightly larger ionic radius, induces lattice distortion, enhancing the self-trapped excitons (STEs) luminescence of the MCZCB and significantly boosting the photoluminescence quantum yield (PLQY) from 70% in pristine Cs₂ZrCl₆ (CZC) to an impressive 95%. Finally, a large-area of 100 cm² and 95% visible light transparent scintillator film is fabricated, achieving a spatial resolution of 25.1 lp mm^-1. This result demonstrates that MSVD technology is promising as a practical strategy for fabricating large-area X-ray imaging film.