水热法合成KGd_(0.9-x)F_4:10%Yb^(3+),x%Er^(3+)微晶及其上转换发光性能

Hydrothermal Synthesis and Upconversion Luminescent Properties of KGd_(0.9-x)F_4∶10%Yb^(3+),x%Er^(3+) Microcrystals

通过水热合成法制备了KGd0.9-xF4∶10%Yb^(3+),x%Er^(3+)微晶,借助X射线粉末衍射(XRD)、扫描电镜(SEM)和荧光分析(PL)对所得样品的晶相结构、形貌和发光性能进行了表征;着重探讨了Er^(3+)掺杂量对样品微观结构及发光性能的影响。XRD结果表明制备的KGd0.9-xF4∶10%Yb^(3+),x%Er^(3+)系列微晶均结晶良好,属于立方晶系,其结晶性随着Er^(3+)含量的增加而增强。SEM表明所有制备的样品均为粒径在0.1~0.3μm范围内的类球形颗粒。荧光光谱显示,在980 nm近红外光激发下,所有样品均出现了位于524 nm和545 nm的绿发射及位于660 nm的红发射,分别对应于Er^(3+)的(2H11/2,4S3/2)→4I15/2和4F9/2→4I15/2能级跃迁。色度坐标图表明制备的KGd0.9-xF4∶10%Yb^(3+),x%Er^(3+)系列微晶均发出较纯的绿光。

Yb3+,Er3+codoped KGdF 4microcrystalshave been synthesized via a facile hydrothermal method.The crystal structure,morphology and luminescent properties of the obtained samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM)and photoluminescence(PL).The influences of doping level of Er 3+ions on the microstructures and luminescent properties of the samples were discussed in detail.XRD results indicated all the as-obtained KGdF 4 microcrystals are well crystalizedand exhibit cubic structure,and the crystallinity increases with increasing amount of Er 3+ions.SEM measurements showed that the KGdF 4 microcrystals are spherical particles with the mean grain sizein range of 0.1-0.3μm.PL results revealed that all the samples display emission peaks located at 524 nm,545 nm and 660 nm under excitation with 980 nm infrared light,ascribed to(2H 11/2,4S 3/2)→4I 15/2 and 4F 9/2→4I 15/2 energy level transitions,respectively.CIE chromaticity diagram revealed that the synthesized KGd 0.9-x F 4∶10%Yb 3+,x%Er 3+microcrystals are pure green emission phosphors.