基于NaYF4的近红外激发上转换发光材料的发光特性

将Yb3+作为协助发光的敏化剂,Tb3+和Tm3+作为发光中心的激活剂分别加入到基质氟化钇钠中,通过水热合成法分别制成不同掺杂浓度的NaYF4:Yb3+/Tb3+和NaYF4:Yb3+/Tm3+双掺杂氟化物纳米发光材料,并通过扫描电子显微镜、X射线衍射以及荧光光谱等手段分别对NaYF4:Yb3+/Tb3+和NaYF4:Yb3+/Tm3+双掺杂氟化物材料纳米颗粒的形貌及其发光特性进行了研究.实验结果表明:系列样品的X射线衍射图谱衍射峰与标准卡片吻合得很好,实验浓度范围内Yb3+/Tb3+和Yb3+/Tm3+共掺没有改变NaYF4的晶体结构.实验得到了该材料在980 nm激光激发下的上转换发光光谱并分析了该材料的上转换发光机理,NaYF4:Yb3+/Tb3+在980 nm激光激发的情况下出现的蓝光,绿光以及红光,分别对应于5D4→7F6、5D4→7F5、5D4→7F1的辐射跃迁;NaYF4:Yb3+/Tm3+在980 nm光源激发下出现强的480 nm的蓝光,对应的是1G4→3H6的电子跃迁能级带,在660 nm强的红光发射谱带,对应的是1G4→3F4能级跃迁辐射光.

Luminous Properties of near Infrared Excited Upconversion Luminescent Materials Based on NaYF4

NaYF4:Yb3+/Tb3+and NaYF4:Yb3+/Tm3+double doping fluoride nanomaterials with different doping concentrations were prepared by hydrothermal synthesis. In these materials,the Yb3+was used as sensitizer to assist in luminous,Tb3+and Tm3+were added to the matrix sodium yttrium fluoride as activators of luminous center. The morphology and luminous properties of NaYF4:Yb3+/Tb3+and NaYF4:Yb3+/Tm3+nanoparticles were investigated by scanning electron microscope(SEM),X-ray diffraction andfluorescence spectrum. The X-ray diffraction patterns of the series of samples well match the NaYF4 standard card. Upconversion luminescence spectra of materials under 980 nm laser excitation were obtained and the mechanism was also analyzed. Excited by 980 nm laser,the emission spectra of NaYF4:Yb3+/Tb3+including blue,green and red light,which correspond to the radiative transition of 5D4→7F6,5D4→7F5,5D4→7F1,respectively. The strong 480 nm emission can be seen in NaYF4:Yb3+/Tm3+excited by 980 nm laser,corresponding to the electron transition energy band of 1G4→3H6. A strong red light emission band centered at 660 nm is corresponding to the 1G4→3F4 energy level transition.