NiTiO_3纳米晶的溶胶-凝胶制备工艺研究

Study on Preparation Technology of NiTiO_3 Nanocrystallites by Sol-gel Method

以无机镍盐和钛酸四丁酯为起始原料,采用溶胶-凝胶法制备了NiTiO3纳米晶。采用X射线衍射(XRD)、综合热分析仪(DSC/TG)以及透射电镜(TEM)对制备的纳米晶进行了测试和表征。研究了不同镍源、后处理温度对钛酸镍纳米晶相组成以及显微结构的影响。结果表明:以硝酸镍为起始原料更易获得单一物相的NiTiO3纳米晶;以硝酸镍为原料,乙醇为溶剂,n(柠檬酸)∶n(Ni2++Ti4+)=1∶1,后处理温度为700℃为制备NiTiO3纳米晶的最佳工艺条件。由谢乐公式推算得出NiTiO晶粒生长符合Brook关系式,计算得到晶粒生长活化能为E=43.07 kJ/mol。

NiTiO3 nanocrystallites were prepared by Sol-gel method using inorganic nickel salt and tetrabutyl titanate as raw materials.The phase composition and microstructures of the as-prepared nanocrystalline were characterized by X-ray diffraction（XRD）,DSC/TG and transmission electron microscopy analysis（TEM）.The influence of the raw material types and the calcination temperature on the phases and microstructures of the powders were investigated.The results show that it＇s easier to obtain pure NiTiO3 nanocrystallites using nickel nitrate as raw material;Monophase and well crystallized NiTiO3 nanocrystallites can be achieved using nickel nitrate as raw material,ethanol as solvent,n（citric acid）∶n（Ni^2＋＋Ti^4＋） = 1∶1,and the calcination temperature at 700 ℃.It is found that the grain-growth kinetics of NiTiO3 nanocrystallites during the calcination follow the Brook＇s theory,and the growth activation energy of NiTiO3 nanocrystallites is calculated to be 43.07 kJ/mol.