偏硼酸钆镁∶铈(Ⅲ)、铽(Ⅲ)、锰(Ⅱ)高显色性荧光粉的研制

Preparation of High Color Rendering Index Phosphor (Gd, Ce, Tb)(Mg, Mn)B_5O_(10)

用高温固相反应法合成了高显色性橙红粉(Gd,Ce,Tb)(Mg,Mn)B5O10,研究了硼酸用量、Tb Ce比例、氢气浓度和灼烧温度等对合成产物发光性能的影响。实验表明,当硼酸过量8%、Tb Ce≥2.5、氢气浓度≤10%、灼烧温度≥1000℃时,可制得发光亮度较高的高显色性橙红色荧光粉。为进一步探讨Tb,Mn的激活机制,制备了高显色性绿粉(Gd,Ce,Tb)MgB5O10和高显色性红粉(Gd,Ce)(Mg,Mn)B5O10作对比。研究表明,通过无辐射能量机制,Ce3+能够有效地将吸收的紫外能量传递给Tb3+,Gd3+作为能量传递过程中的中间体,其作用是增强Tb3+的发光,即发生了"激发→Ce3+→(Gd3+)n→Tb3+→发射"过程。此外,Mn2+发光不能被Ce3+直接敏化,也是通过Gd3+作为中间体,发生Gd3+→Mn2+的能量传递。

The Ce^(3+), Tb^(3+) and Mn^(2+) co-activated high color rendering index phosphor (Gd, Ce, Tb)(Mg, Mn)B_5O_(10) was synthesized by ceramic method. The effects of synthetic conditions, such as the amount of boracic acid, Tb/Ce ratio, the concentration of hydrogen in nitrogen, the calcination temperature, on the luminescence properties were studied. It is shown that the high rendering index phosphor can be obtained when the amount of of boracic acid is added in 8% extra, Tb/Ce ratio is more than 2.5, the hydrogen concentration is less than 10%, and the calcining temperature is higher than 1000 ℃. It is shown that the excitation energy absorbed by Ce^(3+) is transferred to Tb^(3+) through Gd^(3+), through a path indicated as Ce^(3+)→(Gd^(3+))_n→Tb^(3+), resulting in a distinctive Tb^(3+) emission. Similarly, the excitation energy absorbed by Ce^(3+) is transferred to Mn^(2+) through Gd^(3+) as Ce^(3+)→(Gd^(3+))_n→Mn^(2+).