Tb³⁺离子掺杂的Al₂O₃基发光材料的微波水热合成与性能

Microwave Hydrothermal Synthesis and Properties of Rare Earth Doped Al₂O₃ Luminescent Materials

摘要: 以Al(NO₃)₃·9H₂O和尿素为原料，采用微波水热–焙烧法制备了稀土离子Tb³⁺掺杂的Al₂O₃基发光材料。利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、同步热分析仪(TG-DSC)、荧光光谱仪(FS)和Chromaticity Diagram等对产物的结构、形貌、发光性能和CIE色度进行分析和表征。结果表明，在180℃下微波水热30 min，可制备出结晶良好的叶片状勃姆石。勃姆石经不同温度的焙烧，由γ-Al₂O₃向δ-Al₂O₃转变，焙烧后的样品形貌基本保留前驱体的形貌。掺杂Al₂O₃基发光材料的发光来自Tb³⁺的⁵D₄→⁷F_j (j = 3, 4, 5, 6)能级跃迁发射，发光强度随焙烧温度的提高趋于增强，CIE色度随焙烧温度变化不明显，呈绿色。

Abstract: Al(NO₃)₃·9H₂O and urea were used as raw materials to prepare Al₂O₃-based luminescent materials doped with rare earth ions Tb³⁺ by microwave hydrothermal-calcination method. The structure, morphology, luminescence performance and CIE chromaticity of the products were analyzed and characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), Synchronous thermal analyzer (TG-DSC), fluorescence spectrometer (FS) and Chromaticity Diagram. The results indicate that well crystallized leaf shaped boehmite can be prepared by microwave hydrothermal treatment at 180˚C for 30 minutes. Boehmite was calcined at different temperatures, and the morphology of the sample was changed from γ-Al₂O₃ to δ-Al₂O₃, and the morphology of the sample after calcination basically retained the morphology of the precursor. The luminescence of the two Al₂O₃-doped luminescent materials came from the ⁵D₄→⁷F_j (j = 3, 4, 5, 6) energy level transition emission of Tb³⁺, and the luminescence intensity tended to increase with the increase of calcination temperature, while the CIE chromaticity did not change significantly with the calcination temperature, showing green color.