采用高温固相法在还原气氛下合成了Ca9(1-x-y)Al(PO4)7:xCe3+,yDy3+荧光材料,并对其发光特性进行了研究。XRD测试表明所合成样品为纯相Ca9Al(PO4)7晶体。在268 nm紫外光激发下,Ca9Al(PO4)7:Ce3+呈现峰值位于363 nm的宽带发射。在350 nm近紫外光激发下,Ca9Al(PO4)7:Dy3+发射光谱为窄带谱,主峰分别位于483 nm和574 nm,对应Dy3+的4F9/2→6H15/2和4F9/2→6H13/2特征跃迁,呈黄白光发射。荧光光谱表明:Ce3+,Dy3+共掺之后,Ce3+不仅对Dy3+的特征发射有明显的敏化作用,而且通过调节Ce3+和Dy3+的掺杂比例,可实现从黄白光到白光的颜色变化。研究发现:Ca9(1-x-y)Al(PO4)7:xCe3+,yDy3+样品中,掺杂离子的最佳摩尔分数为x=0.02,y=0.02,此时色坐标为(0.306,0.313)。
Phosphors Ca9(1-x-y)Al(PO4)7:xCe3+,yDy3+ were synthesized by sollO-state reacnon method at high temperature under a reducing atmosphere of CO, and the luminescent properties of the phosphors were investigated. The X-ray diffraction patterns (XRD) show that a pure phase of CagAI(PO4) 7 phosphor has been obtained after calcined at 1 200 ℃. Under 268 nm excitation, the Ca9Al(PO4) 7:Ce3+ sample exhibits a broad emission band centered at 363 nm. The emission spec- trum of Cag9Al(PO4)7: DY3+ sample under 350 nm excitation shows two characteristic emissions of Dy3+ located at 483 nm and 574 nm, corresponding with 4F9/2→6H15/2 and 4Fg/2→6H13/2 transition, respectively. According to the fluorescence spectra, the characteristic emissions of Dy3+ are signifi- candy sensitized by Ce3+ when the Ca9Al(PO4)7 samples are co-doped with Ce3+ and Dy3+. Adjus- ting the concentration of Ce3+ and Dy3+, the color of the phosphors can change from yellowish-white to white. The results indicate that the optimal mole fractions of Ce3 + and Dy3+ in Ca9(1-x-y)Al(PO4)7:xCe3+,yDy3+ are x = 0.02 and y = 0. 02, and the chromaticity coordinate is (0. 306, 0. 313).