Application of high thermal stability inorganic scintillator material Ba1.31Ca0.69SiO4:Eu2+,Dy3+ in X-ray imaging

Abstract

Inorganic scintillator materials have garnered widespread attention due to their applications in high-energy X-ray detection and imaging. However, developing materials that possess both high thermal stability and the capability to provide high-resolution X-ray imaging remains a significant challenge in this field. This article reports the synthesis of Ba_1.31Ca_0.69SiO₄ inorganic scintillator materials doped with Eu²⁺ and Dy³⁺ through a high-temperature solid-phase method. Their structure, photoluminescent properties under visible light and X-ray excitation, and thermoluminescence characteristics were thoroughly characterized. Experimental results indicate that the material's traps were enriched through the aliovalent substitution of Dy³⁺, enhancing the afterglow at room temperature. Under 350 nm excitation, the material demonstrated excellent thermal stability (maintaining 90% of its intensity at 150 °C compared to 30 °C) and a high quantum efficiency (IQE = 96.64 %). Furthermore, under X-ray excitation, the material exhibits a high electron storage capacity, which can be read out under near-infrared light at 870 nm, and can be rapidly erased under heating conditions or under visible light at 470 nm. Finally, we prepared flexible films using the phosphor, demonstrating a spatial resolution of 11.9 lp/mm⁻¹ under X-rays, as well as showcasing the real-time and delayed imaging capabilities of the flexible film under X-ray exposure.