结构相转变诱导的发光颜色可调和热稳定性增强的磷酸盐Ca10.5-xSrx(PO4)7:Eu^2+荧光粉

Structure Transformation Induced Tunable-Emissions and Thermal Stability Improvement of Ca10.5-xSrx(PO4)7:Eu^2+ Phosphors

文章采用高温固相法合成一系列发光颜色可调的Ca10.5-xSrx(PO4)7:Eu^2+(0≤x≤8)荧光粉。利用X射线衍射、光致发光、热稳定等多个手段对Ca10.5-xSrx(PO4)7:Eu^2+(0≤x≤8)荧光粉的晶体结构和发光性质进行了详细的研究。通过Sr^2+去部分替换基质中的Ca^2+离子,Ca10.5-xSrx(PO4)7:Eu^2+荧光粉物相结构发生转变,空间群由物相1(0≤x≤4)的R3c转变为物相2(6≤x≤8)的R3m空间群。在近紫外光365 nm的激发下,该样品的发射光谱出现连续的红移,发射主峰从480 nm移动至575 nm,实现了从青光至黄光的连续调控。此外,随着Sr^2+浓度的增加,样品的热稳定得到了明显的提升。因此认为相邻原子替代为设计制备高热稳定性的荧光粉材料提供了思路。

A series of tunable photoluminescence solid solution phosphors Ca10.5-xSrx(PO4)7:Eu^2+(0≤x≤8)phosphors are synthesized by solid state reaction method.The crystal structure and luminescent properties are studied in detail by means of X-ray diffraction,photoluminescence and thermal stability.Experimental results demonstrate that partial replacement of Ca^2+ with Sr^2+ induces structural transformation in Ca10.5-xSrx(PO4)7:Eu2+(0≤x≤8),resulting in the space group changes from R3c in phase 1(0≤x≤4)to R3m in phase 2(6≤x≤8).Under the excitation at 365 nm,the PL spectra shows a continuous red-shift and the main emission peak shiftes from 480 nm to 575 nm,achieving continuous regulation from cyan to yellow light.In addition,as the increasing content of Sr^2+,the thermal stability of Ca10.5-xSr(x PO4)7:Eu^2+(0≤x≤8)is significantly improved.Therefore,we believe that the replacement of adjacent atoms provides an idea for designing phosphor materials with high thermal stability.