The Ca9.95-xNa0.75K0.25(PO4)7:Eu2+0.05, Mn2+x(x=0,0.1,0.2,0.3,0.4,0.5,0.6 and 0.7)phosphors were synthesized by high temperature solid-state reaction, and their phase composition and fluorescence emission properties were studied. Due to the existence of double phases with similar crystal structure, the 5d-4f transition of Eu2+ ions in the phosphors emits a fluorescence of wide wavelength with peaks located at 491 ran and 540 nm respectively. The energy transfer between Eu2+ and Mn2+ , together with the occupation of Mn2+ ions at the eight coordination sites in the phosphors, makes the 4T1(4G)-6A1(6S)transition of Mn2+ ions eimit red emission peaked at 635 ran. The combination of fluorescence emtted by Mnz+ and Euz+ ions results in the emission of white light with color coordinates(0. 333 5, 0. 292 4),(0. 399 9, 0. 317 9)and(0. 330 7, 0. 256 4). The nearly pure white light emitting makes the phosphors show great application potential in the white light-emitting LEDs.%高温固相法合成了Ca9.95-xNa0.75 K0.25 (PO4)7∶Eu0.052+,Mn2+x(x=0,0.1,0.2,0.3,0.4,0.5,0.6和0.7)荧光粉,研究了其相组成和荧光发射性能.结果表明,由于样品中存在着晶体结构相似的双相,使得Eu2+的5d-4f跃迁辐射出峰值分别位于491和540 nm宽谱荧光.同时由于Eu2+-Mn2+之间的能量传递和Mn2+的八配位格位的占据,使得Mn2+的4 T1(4G)-6A1(6S)跃迁产生峰值为635 nm红光发射.Mn2+和Eu2+的荧光组合获得了色坐标为(0.333 5,0.292 4),(0.399 9,0.317 9)和(0.330 7,0.256 4)的白光发射.样品的激发光谱分布在260～450nm的波长范围,这种荧光粉有望在紫外或近紫外激发的白光LED中获得应用.
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