稀土元素掺杂对Y_2SiO_5:Tb发光性能的影响

Influence of Rare Earth Elements (Sc, La, Gd, and Lu) on Luminescent Properties of FED Green Phosphor Y_2SiO∶Tb

系统讨论了La3+,Sc3+,Gd3+和Lu3+掺杂对(Y0.97Tb0.03)2SiO5的光致和阴极射线发光性能的影响,发现不同稀土元素对(Y0.97Tb0.03)2SiO5的发光性能有不同的作用,发光强度与掺杂稀土元素的种类和含量有关。在光致条件下,当La3+,Sc3+,Gd3+和Lu3+掺杂量分别为0.05,0.30,0.30和0.20时,与(Y0.97Tb0.03)2SiO5相比,(Y0.97-xRExTb0.03)2SiO5的发光强度分别变化了+10%,-30%,-15%和+20%。稀土元素掺杂对激活剂有显著的稀释作用,随掺杂稀土元素含量增大,激活剂的猝灭浓度表现出增大的趋势。稀土元素掺杂对(Y0.97Tb0.03)2SiO5的色纯度也有影响,不同稀土元素掺杂后荧光粉发光的色纯度表现出持续升高或降低的趋势。在阴极射线作用下,稀土掺杂(Y0.97Tb0.03)2SiO5的发光强度均得到提高,提高的程度依La3+,Gd3+,Lu3+和Sc3+次序分别为10%,25%,25%和5%～10%。根据稀土元素对发光性能的影响分析了稀土元素掺杂后(Y0.97Tb0.03)2SiO5发光性能产生差别的原因。

The luminescent properties of rare earth doped Y_2SiO_5∶Tb were investigated. For the (Y_(0.97-x)RE_xTb_(0.03))_2SiO_5 (RE=Sc, La, Gd, and Lu) systems, the luminescent intensity varies with the rare earth elements and their contents. For phosphors doped with La^(3+), the luminescent intensity slightly increase. When Gd^(3+) and Sc^(3+) were added to (Y_(0.97)Tb_(0.03))_2SiO_5, the luminescent intensity decreases by 15% and 30% at x=0.3 respectively. For Lu^(3+), the luminescent intensity reached the highest point at x=0.20, and the enhancement is about 20%. In the mean while, color saturation also shows a trend of up and down with the increase of RE^(3+) contents. The cathodoluminescent (CL) intensity with RE^(3+) contents in (Y_(0.97-x)RE_xTb_(0.03))_2SiO_5 (RE=Sc, La, Gd, and Lu) systems was also measured. The doping of RE^(3+) causes an increase in CL intensity, however the enhance extent and optimized RE^(3+) contents were different from that in PL. Doping of Gd^(3+) brings an enormous increase of 25% at x=0.20, which can be interpreted by the energy transfer from Gd^(3+) to Tb^(3+).