以金属硝酸盐为原料,乙二胺四乙酸(EDTA)为络合剂,采用溶胶-凝胶法制备YAG:Ce黄色荧光粉,利用X射线衍射仪、扫描电镜、荧光分光光度计等检测方法研究制备过程工艺参数对粉体结构、形貌和发光性能的影响。结果表明:EDTA络合所得的凝胶经1000℃煅烧就得到纯的钇铝石榴石相(YAG),其晶相转变温度比柠檬酸(CA)络合剂溶胶-凝胶法的降低约200℃,且所得YAG:Ce荧光粉的发光强度随着煅烧温度升高而增大;凝胶经1500℃高温煅烧所得荧光粉的发光强度比柠檬酸(CA)络合剂的提高66.2%,这是由粉体结晶度好、颗粒形貌更规整、呈球形且尺寸更加均匀所致;在原料液中添加Na2SO4-K2SO4复合熔盐后,凝胶经1500℃煅烧后所得荧光粉发光强度比采用非熔盐法所得荧光粉的增大约10%。
Ce-doped Y3Al5O12 (YAG:Ce) yellow phosphors were synthesized by sol-gel method using metal nitrate as raw materials and ethylene diamine tetraacetic acid (EDTA) as complexing agent. The effects of process parameters on the powder structure, morphology and photoluminescence were characterized by X-ray diffractometry, scanning electron microscopy and fluorescence spectrophotometry, respectively. The results show that the pure YAG phase can be prepared by firing gel at 1000℃ for 2 h. Compared with the citric acid (CA) complexing agent sol-gel method, the YAG phase transition temperature of the gel with the EDTA complexing agent sol-gel method can be decreased by about 200℃. The luminescent intensity of the YAG:Ce phosphors increases as the heat temperature increasing because of phosphor with good crystalline and more regular spherical particle. When the gel is sintered at 1500℃, the luminescent intensity of the phosphor improves by 66.2% than that of phosphor with citric acid complexing agent, and the luminescent intensity of the phosphor with Na2SO4 -K2SO4 composite molten salt in reaction liquid can be increased by 10% than that prepared without molten salt method.