以硝酸铈和碳酸氢铵为原料,用双液超声雾化反应法制备了纳米CeO2粉体;用X射线衍射仪和透射电子显微镜分析了雾化温度、焙烧温度、雾化液浓度、表面活性剂等因素对粉体颗粒尺寸和形貌的影响.结果表明:前驱体的物相组成与雾化温度有关,雾化温度60 ℃时制备的纳米CeO2颗粒团聚现象较轻、均匀性好;焙烧温度的提高会使纳米CeO2颗粒迅速长大,比表面积大大减小,200 ℃焙烧较好;雾化液浓度的减小对颗粒尺寸影响不大,但会使其团聚状况有明显减轻,优化的浓度为0.2 mol·L-1;表面活性剂的加入有利于降低雾化液的表面张力,加入体积分数10%乙醇+0.5%聚乙二醇后,有利于生成更细小、粒径更加均匀的球形颗粒;在以上最佳工艺条件下制备的CeO2颗粒尺寸为3 nm.

Nanometer CeO2 particles were prepared by ultrasonic atomization process using cerous nitrate (Ce(NO3)3·6H2O) and ammonium acid carbonate (NH4HCO3) as starting materials.The effect of atomization temperature,calcination temperature,reactants concentration and surface active agent on the phase compositions of precursors and the size and morphology of CeO2 particles were studied by the techniques of XRD and TEM.The results show that the phase compositions of the precursors related to the atomization temperature,and CeO2 nanoparticles prepared at 60 ℃ had less agglomeration and more uniform morphology than other temperature.Increasing the calcination temperature would result in the rapid growth of CeO2 particles and decreased the specific surface area sharply,so the better calcination temperature was 200 ℃.Decreasing reactants concentration had little effect on the particle size,but could improve the agglomeration state obviously,so the selected solution concentration was 0.2 mol·L-1.Surface active agent are favorable for decrease the surface tension of the reaction solution,and smaller and more homogeneity spherical CeO2 particles with particle size of only 3 nm were obtained with 10% ethanol and 0.5% polyethyleneglycol(PEG) as surface active agent under aboving optimum conditions.