采用高温固相反应法制备了NaGdTiO4:Eu^3+红色荧光粉。利用X射线衍射和荧光光谱对NaGdTiO4:Eu^3+粉未进行了表征,研究了TiO2含量和Eu^3+掺杂摩尔分数对粉末晶体结构和发光性能的影响。当TiO2的量在当量反应基础上增加50%时,制得了单一证交相NaGdTiO4。荧光光谱测试结果显示,样品在紫外区存在强的宽激发带,对应于NaGdTiO4基质的吸收。在281nm紫外光激发下,样品显示出强的红光发射,表明NaGdTiO4基质到Eu^3+之间存在有效的能量传递。该类钛酸盐红色荧光粉在近紫外光激发型白光LED中具有潜在的应用价值。
Eu3+ -doped NaGdTiO4 red phosphors were synthesized by conventional solid state reaction method. The effects of TiO2 content and Eu^3+ mole fraction on the crystal structure and photolumineseence properties were investigated by X-ray diffraction and fluorescent spectra. The XRD patterns showed that the resultants with single orthogonal phase structure were achieved when TiO2 content increased by 50% on the basis of stoichiometric reaction composition. In the excitation spectra of single orthogonal structure NaGdTiO4: Eu^3+ phos- phors, by monitoring 618 nm, the charge transfer bands (CTB) of Eu^3+-O2- and NaGdTiO4 matrix absorption centered at around 250 nm and 281 nm were observed, respectively. Under 281 nm excitation, strong red emission was observed at 618 nm originating from the ^5D0→7F2 electric dipole transition of Eu^3+, which suggests that there exist effective energy transfer from NaGdTiO4 matrix to Eu^3+ The calculated emission color coordinates of NaGdTiO4: 20%Eu^3+ are x = 0.63, y = 0.34. These results show that NaGdTiO4: Eu^3+ phosphors might have potential applications in whit light-emitting diodes (LEDs).