硅酸锌锰发光材料的水热-均相沉淀法制备及其性能

为合成结晶度好、分散均匀、性能良好的硅酸锌锰绿色发光材料,以正硅酸乙酯、六水合硝酸锌、四水合醋酸锰为原料,以尿素作沉淀剂,利用水热-均相沉淀法制备了不同二价锰离子掺杂含量的硅酸锌锰绿色荧光粉.采用X射线衍射、扫描电子显微镜、荧光光谱仪对其物相、形貌和发光性能进行了表征,并分析了不同二价锰离子掺杂量对其发光性能的影响.结果表明,在95℃水浴24h,1 250℃煅烧4h时,可以获得粒径为0.2μm,分散均匀、形貌良好、单相的硅酸锌锰.发光性能测试表明:二价锰离子最佳掺杂含量为0.08mol,当掺杂含量超过0.08mol后光谱会发生浓度猝灭效应.

Zn_2SiO_4:Mn^(2+)发光材料的低温合成及其发光性能

采用水热合成工艺低温制备了Mn2+掺杂的Zn2SiO4发光材料,采用X射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscope,SEM)对样品的结构和形貌进行观察,并以此分析了水热过程中Zn2SiO4的形成机制。采用吸收光谱、荧光光谱对其光吸收及光致发光性能进行分析。测试结果表明:水热220℃反应6 d基本可获得完全的Zn2SiO4,产物为短棒状,宽度约为0.25μm,长度约为1μm。吸收光谱显示产物在380,250,220 nm处存在光吸收,并且在253 nm紫外光激发下产生强烈的522 nm绿色发光。

石英颗粒表面合成六棱柱状Mn^(2+)掺杂Zn_2SiO_4及光致发光性能研究

以SiO2颗粒和Zn(CH3COO)2为原料,采用水热法在不锈钢反应釜中低温制备了Mn2+掺杂的Zn2SiO4荧光材料。利用X线衍射仪(XRD)、扫描电子显微镜(SEM)和荧光分光光度计对影响产物结构及发光性能的反应温度、反应时间、NH4OH质量分数等参数进行研究。结果表明:六棱柱状的ZnSiO4纳米颗粒可以在220℃的低温水热条件下获得,以该法制备的Mn2+掺杂ZnSiO4具有良好的光致发光性能,在220 nm紫外光激发下产生525 nm的绿色发光,并且发光强度随水热反应温度、时间以及NH4OH浓度改变而改变。

SOL-GEL SYNTHESIS AND LUMINESCENCE OF GREEN LIGHT EMITTING PHOSPHORS ZN_2SIO4/MN^(2+)

Mn^2＋ doped Zn2SiO4 phosphors were synthesized by sol-gel method, and the influence of zinc source, Mn^2＋ dopant concentration and annealing temperature were investigated. Results show that zinc nitrate based precursor with strong green emission intensities is better than zinc acetate based precursor. The intensity of green light emission reaches a peak at 254 nm when the Mn^2＋ dopant concentration is about 5%（ molar percentage）. Structural details of the phosphors were examined through X-ray diffractometry, thermogravimetric and differential thermal analysis. The result indicates that they are both rhombohedral structures, which remain amorphous below 700 ℃ and crystallize completely around 1000 ℃. The luminescent properties of Zn2SiO4/Mn^2＋ phosphors were characterized by excitation and emission spectra.