Dy3+掺杂YNbO4微晶粉末发光特性（英文）

Luminescence Performance of Dy3+ Doped YNbO4 Microcrystalline Powder

采用高温固相法在1 300℃煅烧2小时制备了不同浓度Dy3+离子掺杂的YNbO4微晶粉末,测量了样品的X射线衍射谱,结果表明生成了纯相YNbO4微晶结构。采用漫反射积分球和光纤光谱仪测量了样品吸收谱,并通过Judd-Ofelt理论计算了Dy3+掺杂YNbO4微晶粉末样品的光谱强度参数Ω2、Ω4、Ω6,以及实验和理论振子强度。测量了监测波长为577 nm的样品激发谱,结果表明在260 nm处有一个强激发峰,其主要由YNbO4晶格吸收产生,在其他波段还有几个较强激发峰,主要归因于Dy3+离子的4f-4f跃迁。测量了270 nm和360 nm波长激发下的发射谱,观察到了相似的发射峰分布。通过不同Dy3+掺杂浓度样品发射峰比较,发现了浓度猝灭效应。根据能量传递理论分析表明,Dy3+离子的浓度猝灭属于电偶极-电偶极相互作用。最后,计算了样品的CIE色坐标,发现最接近于白光区域的色坐标为(0.219, 0.166)。

Microcrystalline powders of YNbO4 with different Dy3+doping concentration were synthesized by the conventional solid-state reaction at 1 300℃and duration of 2 h.Their X-ray diffraction patterns were examined and the results confirmed the formation of single phase crystalline structure of YNbO4.Their absorption spectra were measured through combination of a scattering integral sphere and a fiber spectrometer,and in consequence,spectrum intensity parameters(Ω2,Ω4 andΩ6),experimental and theoretical oscillator intensities of YNbO4∶Dy3+were calculated through Judd-Ofelt theory.Excitation spectra with emission peak at 577 nm were recorded and the results illustrated that there were an excitation peak near 260 nm due to absorption of crystalline lattice of YNbO4 and several excitation peaks originated from 4 f-4 f transition of Dy3+ions.Emission spectra excited at 270 nm and 360 nm were also measured and basically identical emission spectra were observed.Concentration quenching phenomenon of Dy3+ion’s luminescence was discovered by comparing emission spectrum of different Dy3+doping concentration.Analytic results according to energy transfer theory indicated that concentration quenching mechanism in Dy3+ions belonged to dipoledipole interaction.At last,CIE color coordinates of the prepared samples were also calculated and color parameters with nearest distance to white light region were(0.219,0.166).