溶胶-凝胶法制备的BaMgAl10O17:Eu前驱体的晶化过程

采用柠檬酸作为螯合物的溶胶-凝胶法制备了BaMgAl10O17：Eu(barium magnesium aluminate，BAM)蓝色荧光粉，并研究了，其晶化过程。通过X射线衍射、扫描电镜和荧光光谱等表征手段，研究了前驱体晶化过程的焙烧条件、结晶动力学、颗粒大小和发光性能等。BAM晶相在1100℃开始产生。温度达1200℃时，前驱体由无定型态完全转变成BAM晶相。在1120～1300℃时晶化反应的表观活化能为233kJ／mol。在室温下测得荧光粉的最大吸收峰和发射峰分别处在334nm和454nm。合成荧光粉的粒径为5μm左右，其形态和粒径取决于前驱体。

CRYSTALLIZATION PROCESS FOR PRECURSOR OF BaMgAl10O17 : Eu PREPARED BY SOL-GEL METHOD

BaMgAl10 O17 : Eu (barium magnesium aluminate, BAM) blue fluorescent powder was prepared by sol- gel method using citric acid as chelate, and the crystallization process in its synthesis process was studied. The precursor calcination conditions, crystallization kinetics, particle size and morphology of the crystals and fluorescence properties were characterized by Xray diffraction, scanning electron microscopy and fluorospectrophotometer, etc. The BAM crystal began to appear at 1 100 ℃.The precursor was transformed to BAM crystallization from amorphous status at 1 200 ℃. The apparent activation energy and apparent rate constants of the crystallization reaction at different temperatures were obtained. The apparent activation energy is233 kJ/mol when the temperature is 1 120-1 300 ℃. The maximum photoluminescence absorption and the maximum emission at room temperature are 334 nm and 454 nm, respectively. The particle size of the phosphor powder synthesized is around5 μm. The morphology and the particle size depend on the precursor.