Flexible and Transparent Phosphonium-Based Metal Halide Glass Scintillators for High-Resolution X-ray Imaging

Organic–inorganic hybrid metal halides have recently emerged as promising candidates for X-ray imaging, benefiting from their low-cost, high X-ray attenuation coefficient, and high light yield. However, achieving transparent scintillators remains extremely challenging, which is required for high-resolution X-ray imaging in medical and industrial detection. Glassy materials typically have high optical transparency, and more importantly, they can be easily processed into different shapes and scaled up proportionally for large-scale production. Here, large-area, flexible, and transparent scintillators are developed that have ideal optical properties such as high emissivity and low self-absorption. The obtained glassy scintillators exhibit a high transmittance of 90% in the range 450–800 nm, which is very promising for X-ray imaging. A high spatial resolution of 22.2 lp·mm –1 and a low detection limit of 48.39 nGy air ·s –1 were achieved based on the optimized perovskite glass scintillators. Additionally, the phosphonium-based scintillators exhibit remarkable stability under continuous X-ray illumination. The melt-quenching approach is also suitable for upscaling with excellent reproducibility, which addresses the critical issues of perovskite scintillators facing commercialization.