Si_3N_4掺杂氮化对Sr_3SiO_5:Eu^(2+)荧光粉发光性能的影响

Luminescence Properties of Si_3N_4 Doped Nitride Sr_3SiO_5:Eu^(2+) Phosphor

采用高温固相法制备Si_3N_4掺杂氮化Sr_(2.99)SiO_(5-6x)N_(4x):0.01Eu^(2+)荧光粉。采用XRD、EDS和SEM测试结果表明:N^(3-)进入Sr_3SiO_5基质晶格中取代部分O^(2-)离子,形成了单一相Sr_(2.99)SiO_(5-6x)N_(4x):0.01Eu^(2+)固溶体。PL&PLE荧光光谱测试结果显示,Sr_(2.99)SiO_(5-6x)N_(4x):0.01Eu^(2+)荧光粉在344nm紫外光的激发下发射出红橙光,属于Eu^(2+)离子典型的4f65d1?4f7电子跃迁。随着N浓度的增加,Sr2.99Si O5-6xN4x:0.01Eu^(2+)荧光粉发射光谱和激发光谱的强度明显增强。热稳定性测试结果表明,Si_3N_4掺杂氮化能够显著提高Sr3Si O5:Eu^(2+)荧光粉的热稳定性。通过Arrhennius模型拟合结果表明横向穿越过程(crossover)引起的Sr_3SiO_5:Eu^(2+)荧光粉氮化前后的温度猝灭。

Si3N4 doped Sr2.99SiOs.6xN4x：0.01Eu2＋ phosphorssampless were prepared by high temperature solid-state reaction method. Testing results ofXRD, EDS and CHNS of the phosphor samples demonstrated that the nitrogen atoms could be incorporated into the host lattice of Sr3SiO5 through partial occupation of the oxygen atoms sites to form Sr2.99SiO5-6xNax：0.01Eu2＋ solid solution. Under the excitation of 344 nm ultraviolet, the Sr2.99SiOs.6xN4x： 0.01Eu2＋ phosphor samples emit orange lights peaked at 580 nm, which originates from 4f65d1→4f7 transitions of Eu2＋ ions. With the increase of N3＋-ions concentration, the intensities of emission and excitation spectra of Sr2.99SiOs-6xN4x： 0.01Eu2＋ phosphor samples are obviously enhanced. The thermal stability testing results of the phosphor samples show that the incorporation of N3- ions significantly improve the thermal stability better than that of undoped samples. The curves analyzed and fitted by the Arrhennius formula model indicate that the quenching temperature is caused by crossover process.