利用无容器技术制备了(La0.94-xEr0.06Ybx)(Ti0.95Zr0.05)2.25O6(x=0~0.24,间隔0.04)球状透明玻璃,其稀土离子掺杂浓度最大值达到30%。通过DTA分析发现,玻璃具有很好的热稳定性, x=0时玻璃化转变温度Tg和析晶起始温度To分别为818℃和906℃,ΔT(ΔT=To–Tg)为88℃,玻璃形成能力较低。随着Yb3+浓度提高, Tg、To和ΔT逐渐下降,说明Yb3+降低了玻璃的热稳定性和形成能力。利用紫外可见分光光度计测定了样品的吸收/透过光谱,玻璃在975 nm具有很强的吸收峰,表明 Yb3+可以有效提高玻璃对入射光的吸收强度；在可见光范围内除特征吸收外具有近70%的透过率,说明玻璃具有良好的透可见光性能,有望获得高强上转换发光输出。上转换荧光光谱研究表明：在980 nm激光泵浦下,获得了中心位于535、554和672 nm处的绿、红发光带, x=0.16的发光最强,672 nm处的红光强度是x=0的近130倍。上转换发光强度与泵浦功率关系的分析表明：535、554 nm处的绿光和672 nm处的红光发光均是双光子发光过程。%Sphere transparent titanate glasses (La0.94-xEr0.06Ybx)(Ti0.95Zr0.05)2.25O6 (x=0–0.24, in steps of 0.04) were prepared by containerless processing. The DTA curve shows that the glass(x=0) has high glass transition tempera-ture(Tg=818℃) and onset temperature of crystallization(To=906℃). The thermal stability and the glass forming ability decrease with the Yb3+concentration increasing. Strong absorption bands at 975 nm are observed, showing effective absorption of Yb3+at 975 nm. The transmittance is almost 70%in 300-3000 nm except characteristic ab-sorption of Er3+and Yb3+. Three emission bands centered at 535, 554, 672 nm are obtained at the excitation of 980 nm laser. When the Yb3+concentration x is 0.16, the glass sample performs the strongest upconversion luminescence, which emission intensity at 672 nm is almost 130 times as high as that of Er3+-doped glass at room temperature.
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