通过高温固相法合成Ca₂GdZr₂Al₃O₁₂…Mn ⁴⁺等一系列荧光粉,利用X射线粉末衍射仪(XRD)、荧光分光光度计和紫外可见分光光度计对其物相结构和发光性能进行表征。基质结构表明,[ZrO₆]八面体中的Zr ⁴⁺可以被Mn ⁴⁺取代,XRD图谱和不同温度下合成的荧光粉的发光强度表明,1500 ℃为适宜的合成温度。当Mn ⁴⁺掺杂浓度(物质的量分数)为0.0050时,发光强度最大;当检测波长为703 nm时,激发波长随Mn ⁴⁺掺杂浓度的增加从343 nm移动到374 nm。利用光谱数据计算晶体场参数D_q和Racah参数(B和C),结果表明,Mn ⁴⁺处于强场中。Bi ³⁺、Mn ⁴⁺共掺杂可以增强Mn ⁴⁺的发光,荧光寿命测试结果表明,共掺时荧光粉的荧光寿命均长于Mn ⁴⁺单掺荧光粉,存在Bi ³⁺→Mn ⁴⁺的能量传递。

A series of phosphors such as Ca2GdZr2Al3O12…Mn 4+ are synthesized by high-temperature solid-state reaction, and their phase structures and luminescence properties are characterized with X-ray powder diffractometer (XRD), fluorescence spectrophotometer and UV-visible spectrophotometer. The matrix structure indicates that Zr 4+ in the [ZrO6] octahedron can be substituted by Mn 4+. The XRD patterns and the luminescence intensity of phosphors synthesized at different temperatures indicate that 1500 °C is the suitable synthesis temperature. When the doping concentration (mole fraction) of Mn 4+ is 0.0050, the luminescence intensity is the strongest. When the detection wavelength is 703 nm, the excitation wavelength shifts from 343 nm to 374 nm as the increase of the Mn 4+ doping concentration. Using the spectral data to calculate the crystal field parameters Dq and Racah parameters (B and C), the results indicate that Mn 4+ is in a strong field. At the same time, codoping Bi 3+and Mn 4+ can enhance the luminescence of Mn 4+. The fluorescence lifetime test shows that the fluorescence lifetimes of codoped phosphors is longer than that of single-doped Mn 4+, and there is energy transfer of Bi 3+→Mn 4+.