光学碱度对Tb3+掺杂Bi2O3-B2O3玻璃发光性能的影响

采用熔融法制备了Tb³⁺掺杂的Bi₂O₃-B₂O₃系统玻璃，使用激发、发射及拉曼光谱分析了光学碱度与玻璃结构及发光性能的关系，同时绘制了Tb³⁺、Bi³⁺和Bi²⁺的能级图。研究结果表明：Tb³⁺掺杂的Bi₂O₃-B₂O₃玻璃由[BO₃]、[BiO₃]、[BO₄]及[BiO₆]共同组成，且随着光学碱度由0.63增加到0.93，玻璃的结构逐渐疏松。高的光学碱度使部分Bi³⁺变为Bi²⁺，发出571 nm（²P_3/2（2）→²P_1/2）的光，Bi³⁺→Tb³⁺的能量降低。在光学碱度及Tb³⁺、Bi³⁺和Bi²⁺离子的共同作用下，随着光学碱度的提高，玻璃的发光颜色由黄绿色变为白色。

Effect of Optical Basicity on Luminescence Properties of Tb3+ Doped Bi2O3-B2O3 Glasses

Tb³⁺ doped Bi₂O₃-B₂O₃ glasses were prepared by melting technique, and the relationship of optical basicity,luminescence properties and structure were investigated by excitation, emission and Raman spectra. Energy level structures of Tb³⁺, Bi³⁺ and Bi²⁺ ions were plotted for the excitation and energy transfer routes. The results show that Tb³⁺ doped Bi₂O₃-B₂O₃ glasses consist of [BO₃], [BiO₃], [BO₄],and [BiO₆] together as basic structural groups, and its structure turn looses as the optical basicity increasing from 0.63 to 0.93. Based on energy matching condition, 571 nm emission ascribed to ²P_3/2(2)→²P_1/2 transition of Bi²⁺ reduces from Bi³⁺ ions at high optical basicity of glasses, which decreases the transition of Bi³⁺→Tb³⁺. The luminescent properties of Tb³⁺ doped Bi₂O₃-B₂O₃ glasses are quite sensitive to optical basicity, the luminescence color turns to white from yellow-green with the optical basicity increasing.