稀土离子掺杂的氧氟玻璃是一种新型上转换发光材料。制备了Tm3+/Yb3+单掺、共掺的摩尔分数为n(SiO2)=0.30,n(PbF2)=0.50,n=(Al2O3)=0.15,n(AlF3)=(0.049-x),n(TmF3)=y,n(YbF3)=x(x=0,0.001,0.010,0.015,0.020,y=0,0.001)系统氧氟玻璃,研究了其上转换发光特性、分析了其上转换发光机理。研究发现,在970 nm抽运光源激发下,Tm3+单掺时没有可见光上转换发射;而加入Yb3+后产生了强的蓝光(452 nm,476 nm)、红光(647 nm)及近红外光(791 nm)发射,分别对应如下辐射跃迁:1D2→3F4、1G4→3H6、1G4→3F4和3H4→3H6;且随着Yb3+离子浓度的增加上转换发光增强。在970 nm光源抽运下用Yb3+敏化Tm3+可以显著提高其上转换发光强度,且随着Yb3+离子浓度的增加,增强了对抽运光源的吸收并提高了Yb3+到Tm3+的能量转移几率,从而增强了上转换发光强度。

A new oxyfluoride glass system was developed with molar fractions of n(SiO2)=0.30,n(PbF2)=0.50,n=(Al2O3)=0.15,n(AlF3)=(0.049-x),n(TmF3)=y,n(YbF3)=x(x=0,0.001,0.010,0.015,0.020,y=0,0.001) and its upconversion emission properties were investigated. Furthermore the upconversion mechanism was discussed. The experimental results showed that there was not upconversion emission for Tm3+ singly doped glasses under 970 nm excitation. While strong blue (452 nm, 476 nm), red (647 nm) and near infrared (971 nm) emissions were found in Tm3+/Yb3+ codoped glasses, which responded to the following radiative transition: 1D2→3F4, 1G4→3H6, 1G4→3F4 and 3H4→3H6. Moreover, the intensity of upconversion luminescence was strongly dependent on the concentration of Yb3+. It was indicated that under 970 nm excitation the upconversion luminescence intensity of Tm3+ increased with Yb3+ sensitizing. With Yb3+ concentration increasing, absorption of pump source and energy transfer between Tm3+ and Yb3+ were both enhanced, and as a result the upconversion luminescence intensity was increased.