Abstract Mixed crystal strategy is an effective approach to improve the luminescence properties of optical materials and has been adopted widely in many systems. In this paper, the La-mixed Gd2Si2O7:Ce polycrystalline samples were successfully synthesized by a sol-gel method. The crystal structure and luminescence properties were confirmed and discussed by XRD, UV-Vis luminescence spectra, and XEL, respectively. The vacuum ultraviolet excitation spectra and thermoluminescence glow curves were also systematically investigated and discussed at varied temperature. A combination of the first-principles calculations and optical characterization experiments was employed to study the electronic band structure of host material, revealing that the band gap is narrowed and the 5d1 level of Ce3+ is shifting to higher energy as the La content increased. The luminescence thermo-stability and activation energy were also measured and calculated. It indicates that thermo-stability is strongly dependent on the La concentration. An effective approach is developed to tune the electronic band structure, luminescence properties and thermostability of (Gd1–xLax)2Si2O7:Ce scintillator by adjusting La/Gd ratio.

中文翻译：

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(Gd1–La )2Si2O7:Ce 闪烁体通过调节 La/Gd 比可调电子能带结构、发光特性和热稳定性

摘要 混晶策略是提高光学材料发光性能的有效途径，已被许多系统广泛采用。在本文中，通过溶胶-凝胶法成功合成了 La 混合的 Gd2Si2O7:Ce 多晶样品。分别通过XRD、UV-Vis发光光谱和XEL确认和讨论了晶体结构和发光性质。还系统地研究和讨论了不同温度下的真空紫外激发光谱和热释光辉光曲线。结合第一性原理计算和光学表征实验研究了主体材料的电子能带结构，表明随着 La 含量的增加，带隙变窄，Ce3+ 的 5d1 能级向更高能量转移。还测量和计算了发光热稳定性和活化能。这表明热稳定性强烈依赖于 La 浓度。开发了一种通过调节 La/Gd 比来调节 (Gd1–xLax)2Si2O7:Ce 闪烁体的电子能带结构、发光特性和热稳定性的有效方法。