Mg^(2+)掺杂Zn_2SiO_4:Mn^(2+)的溶胶-凝胶法合成及真空紫外发光特性研究

Synthesis and luminescent properties of Mg^(2+)doped Zn_2SiO_4 :Mn^(2+)phosphor under VUV excitation

采用溶胶-凝胶法(sol-gel method)于不同气氛条件下成功合成了Zn1.92-xMgxSiO4:0.08Mn2+(0≤x≤0.12)系列粉末样品.利用X射线衍射(XRD)、光致发光(PL)谱等分析手段对Zn1.92-xMgxSiO4:0.08Mn2+系列荧光粉的结构、晶胞参数、发光性能进行了表征.结果表明:Zn1.92-xMgxSiO4:0.08Mn2+样品中掺杂的Mg2+取代了Zn2+离子格位并形成MgO4四面体,由于MgO4基团约在154nm处有吸收,掺杂适量Mg2+提高了样品的发光强度,Mg最佳掺杂浓度约为0.06mol;热处理气氛显著影响荧光粉的发光强度,前驱体在N2保护气氛下于1100℃保温4h,缓冷至900℃于N2(95%)+H2(5%)的还原气氛下进行热处理,得到的系列荧光粉发光强度最强;经低温还原热处理所得最佳样品Zn1.86Mg0.06SiO4:0.08Mn2+的发光强度是商用粉的105%,衰减时间(3.89ms)较商用粉缩短了1.33ms.

A series of phosphors of Zn1.92-x MgxSiO4：0. 08Mn（0≤x≤0. 12） were successfully synthesized at various heating atmosphere via sol-gel method. The structure and luminescent properties of the samples were characterized by X-ray diffractometer （XRD） and the FLS920T Spectrophotometer,respectively. The results indicated that in the Zn1.92 SiO4：0. 08Mn system,the Mg2 ＋ doped could substitute for the Zn2 ＋ site and result in the decrease of lattice parameters. The absorption band of the MgO4 cluster was located at about 154 nm in vacuum ultraviolet region. Mg2 ＋ ion doping has favorable influence on the photoluminescence properties of Zn2SiO4：Mn2 ＋ ,the optimum concentration of Mg^2 ＋ being 0. 06 mol under 147 nm excitation. The emission intensity of Zn1.92 -xMgxSiO4：0. 08Mn^2 ＋ phosphors calcined in the mixture of nitrogen and hydrogen were stronger than those of the phosphors calcined in other heating atmospheres,and the emission intensity of Zn1.86Mg0.06SiO4：0. 08Mn^2 ＋ calcined in the mixture of N2 and H2 was 113% of that of Zn1.92SiO4：0. 08Mn^2 ＋ ,being 5% higher than that of commercial phosphor. After Mg^2 ＋ doping the decay time of phosphor was much shortened and the decay time of Zn1.86Mg0.06SiO4：0. 08Mn^2 ＋ was 3. 89 ms,which was shorter by 1. 33 ms than that of commercial product.