溶胶-凝胶法制备La2Ce2O7:Eu3+及其发光性能

采用溶胶-凝胶法（Sol-gel）合成La₂Ce₂O₇:Eu3+系列红色荧光粉，并研究煅烧温度、Eu3+掺杂浓度以及不同种类电荷补偿剂对样品发光性能的影响.通过XRD、SEM、荧光光谱对样品的晶体结构、形貌以及发光性能进行测量和表征.结果表明:实验所得样品主晶相为La₂Ce₂O₇，属于萤石结构. Eu3+及电荷补偿剂的掺杂没有改变其晶体结构.合成的样品在467 nm蓝光激发下发出612 nm的红光.样品的发光强度随煅烧温度以及Eu3+掺杂浓度的提高先增强后减弱，样品的较优的煅烧温度为1 100 ℃，Eu3+较优的掺杂浓度为10 %（摩尔百分比）.掺入电荷补偿剂可以有效增强样品的发光强度，其中掺入Li+后发光增强的效果最显著. 

Synthesis of La2Ce2O7: Eu3+ by sol-gel method and its photoluminescence properties

Red phosphorsof the La₂Ce₂O₇:Eu3+ were synthesized by sol-gel method. The effects of calcination temperature, Eu3+ doping concentration and different kinds of charge compensations on the luminescent properties were also studied in this paper. The crystal structure, surface morphology and luminescent properties of the samples were measured and characterized by XRD, SEM, and fluorescence spectrum. The results show that the main crystal phase of samples is La₂Ce₂O₇, which is single-phased fluorite structure.Its crystal structure has not been changed by Eu3+ion and charge compensations. Under the blue light excitation of 467 nm, the characteristic red emission at 612 nm is detected. The emission intensity increases and then decreases with the increasing of the sintering temperature and Eu3+ ion concentration. The optimum sintering temperature and Eu3+ ion concentrationare 1 100 ℃ and 10 mol%, respectively. The emission intensity could be enhanced efficiently by doping charge compensations and the best luminescent performance could be derived when the sample is co-doped with Li+ ion.