中文摘要：

以柠檬酸为络合剂，采用微波辅助溶胶–凝胶法制备了 CaLa2（MoO4）4：Eu3＋红色荧光粉。研究了前驱体的热分解历程，分析表征了样品的结构、形貌和发光性能。探讨了焙烧温度、Eu3＋掺杂量、柠檬酸与乙二醇摩尔比和硼酸用量等对样品发光性能的影响。结果表明：前驱体经700~900℃焙烧均能得到目标产物 CaLa2–x（MoO4）4：xEu3＋，样品具有白钨矿结构，属于四方晶系。样品的激发光谱在250~350 nm 处有一宽吸收带，对应于 Mo–O，Eu–O 电荷迁移带；在395和464 nm 处存在很强的吸收峰，归属于 Eu3＋的4f–4f 跃迁。发射光谱主峰位于616 nm 处，归属于 Eu3＋的5D0→7F2电偶极跃迁发射。前驱体经800℃焙烧所得样品发光强度最大，且发光强度随着 Eu3＋掺杂量的增加而增大，在 x=0.2~1.0范围内未出现猝灭现象。体系中加入适量乙二醇，可以起到细化晶粒、提高粉体分散性的作用，但浓度过高则会降低样品的发光强度；助熔剂硼酸的用量对样品发光强度影响较大，当用量为3%时，样品的发光性能较好。

英文摘要：

The red-emitting CaLa2（MoO4）4：Eu3＋ powders were prepared by a microwave-assisted sol-gel method, with citric acid as a chelating agent. The heat decomposion mechanism of the precursor, phase structure, morphology and luminescent properties of the samples were characterized. The influences of calcining temperature, Eu3＋ content, mole ratio of citric to ethylene glycol （EG） and the dosage of H3BO3 on the luminescent properties of the samples were investigated. The results indicate that the target products of CaLa2–x（MoO4）4：xEu3＋ are synthesized by calcining precursor in a temperature range from 700 ℃ to 900 ℃. The products are readily indexed to a pure tetragonal phase with scheelite structure. The excitation spectra consist of a broad band at 250–350 nm and the intense lines at 395 nm and 464 nm. The former is attributed to the Mo–O and Eu–O charge transfer transition, and the latter is due to 4f–4f transitions of Eu3＋ ions. In the emission spectra, the main peak centered at 616 nm corresponds to the 5D0→7F2 electronic dipole transition. The luminescence intensity of the sample obtained at 800 ℃ is the maximum, and it increases gradually with the increase of Eu3＋ concentration. Little concentration quenching occurs when the value of x is in the range of 0.2–1.0. In addition, the addition of an appropriate amount of ethylene glycol in the solvent may contribute to the grain refinement and the powder dispersion. A high concentration of ethylene glycol will reduce the luminescence intensity of the sample. The dosage of flux H3BO3 has a great effect on the luminescence intensity of the sample. When the dosage of H3BO3 is 3%, the luminescence intensity of the sample shows better luminescent properties.