均相沉淀法制备γ-La2S3粉体及球形形貌控制研究

Preparation and Spherical Morphology Control of γ-La_2S_3 Powders by Homogeneous Precipitation

以La2O3和尿素为原料,丙三醇为分散剂,采用均相沉淀方法制备镧盐前驱体,并通过H2S硫化得到γ-La2S3粉体。采用X射线衍射仪和扫描电子显微镜对镧盐前驱体和γ-La2S3粉末的结构和形貌进行表征。结果表明,当加热温度为95℃,尿素和La2O3的物质的量比为15∶1,V(丙三醇)/V(水)=1∶1,反应时间为3 h时,可制备出高纯、分散性好、球形γ-La2S3纳米粉体。

Carbonate lanthanum precursors were synthesized by homogenous precipitation using lanthanum oxides and urea as raw materials,then sulfidized to γ-La2S3 powders.The structure and morphology of precursors and γ-La2S3 powders were investigated by X-ray diffraction（XRD） and scanning electron microscopy（SEM）,respectively.The optimal conditions for preparing the pure,spherical particles γ-La2S3 powders with good sintering behavior are as follows： reaction temperature is 95 ℃,mole ratio of urea to La2O3 is 15∶ 1,volume ratio of glycerol to water is 1∶ 1 and reaction time is 3 h.