Characterization of Superfine Sr_2CeO_4 Powder Prepared by Microemulsion-Heating Method  

作　　者：邢德松 龚孟濂 邱学青 杨东杰 谢国伟 

机构地区：[1]School of Chemical and Energy Engineering, South China University of Technology, Guangdong Provincial Laboratory of Green Chemical Technology, Guangzhou 510640, China [2]State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China [3]Department of Physics, Hong Kong Baptist University, Hong Kong , China [4]不详

出　　处：《Journal of Rare Earths》2006年第3期289-293,共5页稀土学报（英文版）

基　　金：ProjectsupportedbytheNaturalScienceFoundationsofGuangdongProvince(021716,980342)andtheScientificandTechnologicalProjectsofGuangdongProvince(B10502)

摘　　要：Powder phosphor of Sr2CeO4 is prepared by microemulsion-heating method and a film of the phosphor on ITO glass is formed by electrophoretic deposition. Field emission scanning electron microscopy （FE-SEM） images show that the powder fired at 850 ℃ for 4 h has a spherical shape with an average diameter of 70 - 80 nm whereas the powder sintered at 900 ℃ for 4 h and 1000 ℃ for 4 h have shuttle-like and spherical shapes, respectively, with both sizes less than 1μm. X-ray diffraction （XRD） pattems indicate that the superfine Sr2CeO4 exhibits an orthorhombic crystal structure. Roomtemperature photoluminescence （PL） measurements show that there are three excitation peaks located at around 262, 280 and 341 nm, and all the Sr2CeO4 samples display an intense blue emission at 470 nm with CIE coordinate of （x, y） = （0.176, 0.283）. The quantum yield of phosphor is high up to 0.47 ±0.04. Compared with Sr2CeO4 samples prepared with traditional high-temperature heating, the phosphor synthesized with this method has a smaller size, lower calcination temperature, and shorter calcination time, and the main excitation and emission bands are blue shifted about 30 and 12 tun respectively. The startup voltage for Sr2CeO4 film on ITO glass shifts from 2700 to 4000 V with increasing thickness of the film.Powder phosphor of Sr2CeO4 is prepared by microemulsion-heating method and a film of the phosphor on ITO glass is formed by electrophoretic deposition. Field emission scanning electron microscopy （FE-SEM） images show that the powder fired at 850 ℃ for 4 h has a spherical shape with an average diameter of 70 - 80 nm whereas the powder sintered at 900 ℃ for 4 h and 1000 ℃ for 4 h have shuttle-like and spherical shapes, respectively, with both sizes less than 1μm. X-ray diffraction （XRD） pattems indicate that the superfine Sr2CeO4 exhibits an orthorhombic crystal structure. Roomtemperature photoluminescence （PL） measurements show that there are three excitation peaks located at around 262, 280 and 341 nm, and all the Sr2CeO4 samples display an intense blue emission at 470 nm with CIE coordinate of （x, y） = （0.176, 0.283）. The quantum yield of phosphor is high up to 0.47 ±0.04. Compared with Sr2CeO4 samples prepared with traditional high-temperature heating, the phosphor synthesized with this method has a smaller size, lower calcination temperature, and shorter calcination time, and the main excitation and emission bands are blue shifted about 30 and 12 tun respectively. The startup voltage for Sr2CeO4 film on ITO glass shifts from 2700 to 4000 V with increasing thickness of the film.

关 键 词：PHOSPHOR chemical synthesis X-ray diffraction LUMINESCENCE rare earths 

分 类 号：O614.33[理学—无机化学]