Eu²⁺-doped glass has attracted considerable interest due to its dual functionality in X-ray imaging and white light-emitting diodes (LEDs). However, the amorphous nature of glass restricts the improvement of the luminescent efficiency of Eu²⁺-doped glass. Here, four strategies, including selecting oxyfluoride glass as the host, regulating optical basicity, introducing appropriate heavy elements, and adding carbon powders as reducing agents, were proposed to prepare Eu²⁺-doped glass with excellent X-ray excited luminescence (XEL) and efficient blue–cyan photoluminescence (PL). For scintillating performance, the optimal glass exhibits a record-breaking XEL intensity reaching 308% of that of commercial Bi₄Ge₃O₁₂. Together with high transmittance (> 80% at 472 nm), linear response to X-ray dose, and low detection limit (6.0 μGy_air/s), the imaging resolution based on optimal glass reaches 24 lp/mm. For PL performance, the intense blue–cyan light of the optimal glass possesses a high external quantum efficiency of 71.2% and excellent thermal stability (the PL intensity at 423 K is 57.7% of that at room temperature). When combined with the 400-nm chip, the optimal glass effectively fills the cyan gap and elevates the color rendering index of the white LED to 91.8. This work offers valuable guidelines and design principles for improving the XEL and PL performance of Eu²⁺-doped glass.

Because of the requirements of high-temperature industrial flaw detection and oil exploration, glass scintillators for application in high-temperature X-ray imaging have attracted great interest from researchers. In this work, dual-channel thermally enhanced energy transfer (ET) is proposed to improve the thermal stability of Tb³⁺-doped glass scintillators with excellent scintillating performance. One channel is the thermally enhanced ET from Ce³⁺ to Tb³⁺ by codoping with Ce³⁺, and the other channel is the thermal compensation effect from traps to Tb³⁺ with increasing density of traps by codoping with Ce³⁺. The obtained glass scintillators possess high transmittance (exceeding 86.6% at 542 nm), excellent X-ray excited luminescence (XEL) intensity (365% of that of Bi₄Ge₃O₁₂ (BGO)), and superior imaging resolution (24 lp/mm). In addition, anti-thermal-quenching luminescence in XEL (the XEL intensity (I_XEL) at 573 K is 168% of that at 303 K) is achieved. All the results undeniably demonstrated that the designed Ce³⁺ and Tb³⁺ codoped glass scintillators have significant potential for high-temperature X-ray imaging. Dual-channel thermally enhanced ET is beneficial for the development of Tb³⁺-doped glass scintillators with superior scintillating performance and excellent thermal stability.

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.

Developing scintillators with high light yield (LY), superior irradiation stability, and weak afterglow is of significance for the realization of low-dose high-resolution X-ray excited optical luminescence (XEOL) imaging. Lanthanide doped fluoride nanoparticles possess low toxicity, superior environmental stability, facial fabrication process, and tunable emissions, which are appropriate candidates for the next generation nanoscintillators (NSs). However, the low LY and strong positive hysteresis greatly restrict their practical application. Here, we propose an effective strategy that engineers energy gap to significantly enhance the LY. Our results verify that the tetragonal LiLuF₄ host benefits the crystal level splitting of Tb³⁺ ions, which greatly promotes the electrons population on the Tb³⁺:⁵D₄ level followed by the enhanced LY. The LY of LiLuF₄:Tb@LiLuF₄ NSs is calculated to be ~ 31,169 photons/MeV, which is much higher than the lead halide perovskite colloidal CsPbBr₃ (~ 21,000 photons/MeV) and LuAG:Ce (~ 22,000 photons/MeV) scintillators. Moreover, the positive hysteresis is remarkably restricted after coating a thin shell. The X-ray detection limit and spatial resolution are measured to be ~ 21.27 nGy/s and ~ 7.2 lp/mm, respectively. We further verify that this core/shell NS can be employed as scintillating screen to realize XEOL imaging under the low dose rate of 13.86 μGy/s. Our results provide an effective route to develop high performance NSs, which will promote great opportunities for the development of low-dose high-resolution XEOL imaging devices.

Ultra-broadband near-infrared (NIR) luminescence of bismuth ions in glass is widely used, but the stability problem of Bi NIR centers limits its practical application. Therefore, in this work, the original local excess charge model that can effectively regulate the Bi NIR luminescence behavior was expanded and supplemented in bismuth doped yttrium aluminum-silicate glass. The statistical excess charge field around Bi was built up via either introduction of glass modifier (Y³⁺) or substitution of silicon by different glass former ions with a valence state lower than +4 (Al³⁺) in yttrium aluminumsilicate glass. As a result, the behavior of Bi NIR centers (i.e., the valence states of Bi, the intensities and peak positions of absorption and NIR emission) was determined. Also, the distribution characteristics of Bi NIR centers were proposed. Bi⁰ NIR centers are preferentially located in the multimember rings of silicon, while Bi⁺ NIR centers are situated at the interstices of silicon network. This work could solve a problem to stabilize Bi NIR centers in yttrium aluminumsilicate glass, even other alkali metals and alkali metals (Li/Na/K, Mg/Ca/Sr/Ba, etc.) aluminumsilicate glass, thus establishing the experimental and theoretical supports for the design of Bi-doped laser glasses and fabrication of fibers in future. This work also verified the effectiveness and universality of the local excess charge model, providing a strategy for stabilizing the valance state of other multivalent luminescent ions (i.e. Eu, Ce, Cu, Ag, Sn) and their distribution in glass network structure.