Cu⁺-doped oxyfluoride glass with anti-thermal-quenching luminescence for X-ray imaging and WLED

Glasses are considered as promising luminescent materials because of their superior physicochemical stability, cost-effectiveness, and convenient preparation. The development of thermally stable glass scintillators for multi-scenario applications without compromising luminescent efficiency remains a rigorous challenge. In this work, a Cu⁺-doped oxyfluoride glass is designed for X-ray imaging and white light-emitting diode (WLED) by adopting strategies involving the selection of an oxyfluoride glass host, introduction of heavy element, incorporation of the reducing agent Al, and utilization of energy transfer from traps to Cu⁺. For glass scintillators, the optimal sample exhibits excellent X-ray excited luminescence (XEL) intensity (311% of that of Bi₄Ge₃O₁₂ (BGO)) and remarkable resolution for X-ray imaging (24 lp/mm). Benefiting from thermal compensation via the release of electrons from traps, the XEL intensities at 423 and 573 K are 155% and 63% of that at 303 K, respectively. The anti-thermal-quenching luminescence in XEL contributes to achieving a high resolution (24 lp/mm) in high-temperature X-ray imaging. For WLED phosphors, the optimal sample demonstrates an outstanding external quantum efficiency (EQE = 81.0%), which is attributed to the high transparency and low phonon energy of the oxyfluoride glass, slight self-absorption of Cu⁺, and effective reduction by Al. Its photoluminescent (PL) intensity at 573 K remains at 76% of that at 303 K. The full-spectrum WLED fabricated using Cu⁺-doped glass has a high color-rendering index of 96.1. This work provides insights into the development of efficient glass scintillators with anti-thermal-quenching luminescence and paves the way for their multi-scenario applications.