用溶胶-凝胶法和高温固相反应分别制备了纳米量级和常规尺度的稀土正硼酸盐荧光粉LnBO3:Eu(Ln=Y,Gd),测量了它们的激发光谱并首次观察到了YBO3:Eu中Eu3+的7F05D0跃迁的Nephelauxetic效应. 根据低温下的激发光谱，发射光谱以及变温条件对发光光谱的影响, YBO3中Ln3+所占据的两种格位的对称性被修正为C3?和D3. 在不同方法制备的样品中观察到了不同的发光强度和猝灭浓度. 缺陷?的影响是产生这种不同的原因. 退火样品的发光和拉曼散射谱的变化反映出掺杂的杂质Eu3+的团聚化是可能的缺陷来源.
LnBO3:Eu(Ln=Y,Gd)orthoborates were prepared by solid state reaction and sol-gel technique. Nephelauxetic effect was observed in the 7F0?5D0 transition of Eu3+ in a pseudo-vaterite type YBO3 when the excitation spectra were carried out at different temperatures. According to the luminescence of YBO3:Eu at low temperatures and the effect of different temperatures on the luminescence, the site symmetries of Ln3+ in YBO3 were revised to be a D3 and a similar C3. Different luminescent intensities and quenching concentrations were found for the sol-gel samples and corresponding solid-state-synthesized ones. The effect of defects or dislocations was taken into account to explain these phenomena. The luminescence of annealed samples and the Raman spectra of them suggested the presence of Eu3+ clusters in the sol-gel crystalline YBO3:Eu.
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