KAlF_4∶Ce,Gd磷光体的荧光特性及能量传递

Luminescence Properties and Engergy Transfer between Ce^(3+) and Gd^(3+) Ions in KAlF_4∶Ce,Gd

采用溶液反应和固相反应 ,分别合成了KAlF4 基质化合物及KAlF4 ∶Gd和KAlF4 ∶Ce ,Gd等磷光体 ,研究了它们的光谱特性。结果表明 ,KAlF4 ∶Gd无论在短波或长波紫外辐射激发下 ,均无任何吸收和发射。在KAlF4 ∶Ce,Gd中 ,Ce3 + 离子能有效地将能量传递给Gd3 + 离子 ,使Gd3 + 产生了特征锐发射 ,且发射强度很大。但当Ce3 + 浓度固定不变 ,改变Gd3 + 的浓度时 ,Gd3 + 的 6P1/ 2 → 8S7/ 2 发射强度随Gd3 + 浓度的增大反而减弱。

The matrix KAlF 4 was prepared with a reaction of mixtures of solution K 2CO 3 upon certain solution of Al(OH) 3 plus HF(40%),dehydrating at 100 ℃ and annealing for 48 h at 450 ℃.A series of phosphors KAlF 4∶Ce,Gd were synthesized by a solid reaction method.Their excitation and emission spectra were determined.It was observed that Ce 3+ could sensitize Gd 3+ in KAlF 4 effectively,so as to enhance the emission of Gd 3+ significantly.But emission intensity of Gd 3+ 6P 1/2 → 8S 7/2 decreased with the concentration of Gd 3+ increased when the concentration of Ce 3+ was constant.