无团聚YAG:Ce~(3+)荧光粉的制备与表征

采用共沉淀-喷雾干燥法制备YAG∶Ce3+荧光粉。前驱体经热处理、研磨、酸洗碱洗后形成荧光粉。研究了前驱体料浆浓度、热处理条件、研磨、酸洗碱洗对粉末晶相、颗粒形貌、粒度和发光性能的影响。研究发现:料浆浓度为0.2,0.4,0.6 mol/L时,前驱体颗粒形貌分别呈碎屑、光滑和褶皱状球形;无团聚光滑球形前驱体经1 100℃热处理4 h后,XRD未检测到杂相;继续升温至1 550℃,荧光粉相对亮度随之提高;酸洗碱洗能够去除碎屑,获无团聚荧光粉,提高相对亮度。

Preparation and Characterization of Agglomerate-free YAG: Ce3+ Phosphor by Co-precipitating and Spray Drying

Co-precipitation together with spray dry processing was introduced to prepare YAG:Ce3+ precursor first time. YAG:Ce3+ phosphor could be obtained after heat-treating, milling and further acid and alkali washing. Effects of spray suspension concentration, heat treatment temperature and the acid and alkali washing on particle morphology, type of crystal phase and photoluminescence (PL) intensity of the powder were investigated. The precursor particles appeared nearly spherical balls with fragments in the surface, smooth or rugged ones when the concentration of spray suspension was 0.2, 0.4 and 0.6 mol/L, respectively. YAG phase could be obtained by heat-treating the smooth spherical precursor at 1 100 ℃ for 4 h. The PL intensity of the powder raised with heat-treating temperature increased up to 1 550 ℃. Agglomerate-free YAG:Ce3+ phosphor with good preferences could be obtained by acid and alkali washing which could remove scraps adhering on particles and break aggregates between them.