溶胶-凝胶法制备Ca_3Al_2O_6:Eu^(3+)红色荧光粉及其发光性能

Preparation of Ca_3Al_2O_6:Eu^(3+) red phosphor by sol-gel method and its photoluminescence properties

采用溶胶-凝胶法合成Ca_3Al_2O_6:Eu^(3+)红色荧光粉,通过XRD、SEM、荧光光谱分别对样品的结构、形貌以及发光性能进行表征,讨论煅烧温度、Eu^(3+)掺杂浓度以及电荷补偿剂对样品发光性能的影响.结果表明:实验所得样品的结构与Ca_3Al_2O_6相同,Eu^(3+)掺杂并没有改变其晶体结构.合成的荧光粉在394 nm近紫外光激发下发出615 nm明亮的红光.样品的红光强度随着煅烧温度的升高先增加后减弱,最佳烧结温度为1 200℃.同样红光强度也随着Eu^(3+)掺杂浓度的增加先增加后减弱,最佳Eu^(3+)掺杂浓度为4%(摩尔分数).加入电荷补偿剂后样品的发光强度均增强,其中加入K^+后发光增强的效果最显著.该铝酸盐红色荧光粉性质稳定,在白光LED近紫外芯片激发中具有潜在的应用.

The Ca_3Al_2Ov6：Eu^（3＋）red phosphor was synthesized by sol-gel method.The structure,shape and luminous property of the sample were characterized by the XRD,SEM,and fluorescence spectrum to investigate the in-fluence of sintering temperature,Eu^（3＋） ion doping concentration,and charge compensations doping on the sample.The results show that the sample′s crystal phase is the same with Ca_3Al_2O_6 crystal structure and their crystal structure does not change with the invasion of Eu^（3＋） ion.The synthesized phosphor,excited by 394 nm NUVlight,emits 615 nm bright red light.The emission intensity rises first with the increasing of the sintering tem-perature and then decreases and reaches at peak when sintering temperature is 1 200 ℃.At the same time,the emission intensity of the sample increases first and then decreases with the increasing of the concentration of Eu^（3＋） ion and the optimal doping concentration of Eu^（3＋） ion is 4 mol %.Besides,the emission intensity rises with doping charge compensations which doped with K＋ion has the best luminescent properties.This red phosphor of aluminates is stable,which has potential application prospect in the stimulating of White-LED′s NUV-chip.