Tb掺杂SiO_2-B_2O_3-NaF玻璃的制备及发光性质

Synthesis and Luminescent Properties of Tb-doped SiO_2-B_2O_3 NaF Glass

使用正硅酸乙酯、硼酸和氟化钠为前驱体,0.10mol·L-1TbCl3溶液为掺杂剂,通过溶胶-凝胶方法制备了Tb3+掺杂的SiO2-B2O3-NaF玻璃,研究了Tb3+在SiO2-B2O3-NaF体系中的发光性质,结果显示发光体能产生强的绿色发光(544nm),归属于Tb3+的5D4—7F5电子跃迁.Tb3+含量不同时,除发光强度不同外,其发射光谱基本相同,并且在低掺杂Tb3+样品和低退火温度样品中检测到了来自5D3跃迁产生的峰,其跃迁随Tb3+掺杂浓度的增加和退火温度的升高而发生猝灭,这种现象归因于5D3-5D47F6—7F0和/或5D3—7F07F6—5D4跃迁中发生了交叉弛豫现象.Tb3+在SiO2-B2O3-NaF玻璃中的激发光谱由一个宽峰和一系列窄峰组成,宽峰最大波长位于230nm,对应于Tb3+的4f8—4f75d1跃迁,一系列窄峰位于300～380nm处,归属于4f8跃迁,所有发光材料的XRD和TEM测试显示材料是非晶态的.

Tb doped SiO2 B2O3 NaF glass was prepared by sol gel process,using tetraethoxy silcane,boric acid and sodium fluoride as precursors,0.10 mol· L- 1 TbCl3 solution as the dopant.The luminescent properties of Tb3+ doped SiO2 B2O3 NaF phosphors were investigated.The phosphors showed prominent luminescence in green,due to the electronic transition of 5D4- 7F5(Tb3+ ).For all Tb3+ concentrations used the emission spectrum was essentially the same with the exception of intensity and weak peak belonging to transition from 5D3 was detected in lower Tb3+ doped samples and lower annealing temperature samples.The intensity of emission from 5D3 quenches with increasing of the Tb3+ concentration and annealing temperature.The observation showed that cross relaxation obviously took place in the transition 5D3- 5D4 7F6- 7F0 and/or 5D3- 7F0 7F6- 5D4.The excitation spectra of Tb3+ emission in SiO2 B2O3 NaF glass consist of broad bands with a maximum at about 230 nm,corresponding to 4f 8→ 4f 75d 1 transition of Tb3+ ion,and a series of sharp lines in the range of 300 to 380 nm which belong to transitions between the energy levels of the 4f 8 configuration.The structural characterization of these luminescent materials were carried by using XRD and TEM.The results showed that the phosphor was in amorphous phase.