The novel green-emission phosphors (Ce0.67Tb0.33) Mg1-xA111O19: xMn2+ have been prepared at 1 300℃ by solid-state reaction method. The crystal structure and photoluminescence properties were characterized by XRD and fluorescence spectra, respectively. The results show that ( Ce0.67Tb0.33)Mg1-xAl11O19:xMn2+ has the same crystal structure with the typical commercial green phosphor ( Ce0.67Tb0.33) MgAl11O19 ( CMAT) . The excitation spectrum consists of a broad band range from 237 to 326 nm centered at 291 nm, which can be attributed to the characteristic excitation peaks of Ce3+. While excited under ultraviolet light, the phosphors exhibit not only the characteristic emission peaks of Tb3+ at 490, 541, 590 and 620 nm, but also a new broad emission bandrnaround 516 ntn, which is assigned to the 4T1g(G)→6A1g( S) electron transition of Mn2+. The integral area of the emission spectrum increases while doped with Mn2+ as a co-activator, and the integral area is about 226% of CMAT as x = 15. 0% , and the CIE 1931 chromaticity coordinates of Mn2+ doped phosphors (0. 194, 0. 695 ) are closer to the NTSC standard values (0. 21, 0. 71) while compared with CMAT (0. 288, 0. 572). The results indicate that this new phosphor has a higher luminous efficiency in green area and color purity than that of CMAT, and it has a promising application in display fields.%采用高温固相法成功地合成了新型高效绿色荧光粉(Ce0.67Tb0.33)Mg1-xAl11O19∶xMn2+.通过XRD和荧光光谱等对其结构及发光性能进行了系统研究.结果表明:新合成的(Ce0.67Tb0.33) Mg1-xAl11O19∶xMn2+与典型的商用绿粉(Ce0.67Tb0.33) MgAl11O19(CMAT)具有相同的晶体结构；激发光谱处于237 ～ 326 nm范围内,由一个峰位位于291 nm的宽激发带组成,这是典型的Ce3+的特征激发；在紫外光激发下,该荧光粉除了在490,541,590,620 nm存在Tb3+的特征发射峰外,还在516 nm出现了一个较强的归属于Mn2+的4T1g(G)→6A1g(S)电子跃迁的宽发射峰.Mn2+作为共激活剂增大了该荧光材料在绿色区域的发射面积,其中(Ce0.67Tb0.33) Mg0.850Al11O19∶0.150Mn2+荧光粉发射光谱的积分面积最大,为CMAT的226％,其CIE坐标为(0.194,0.695),比CMAT(0.288,0.572)更加接近NTSC标准值(0.21,0.71),即Mn2+的引入不但提高了荧光粉的发光效率,而且改善了其色纯度.结果表明新型(Ce0.67Tb0.33) Mg1-xAl11O19∶xMn2+绿色荧光粉比传统的CMAT在显示领域具有更好的潜在应用前景.
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