Preparation and characterization of nanometer-sized barium titanate powder by complex-precursor method

A new complex-precursor method was proposed to prepare nanometer-sized BaTiO3 powder. Firstly, [Ti2O(O2)2(ta)2]4− complex ions were prepared by the reaction of H2O2, Ti4+ and ta3− (ta=[C6H6O6N]3−) with a desirable amount of surface active agent, and then the Ba2[Ti2O(O2)2(ta)2]·2H2O precursor was obtained by reaction between [Ti2O(O2)2(ta)2]4− and Ba2+. Finally, the precursor was annealed at 800 °C for 2 h to obtain BaTiO3 powder. The morphology, the particle size distribution, the purity and the molar ratio of Ba to Ti of BaTiO3 powder were investigated systematically by TEM, XRD, IR, Raman and chemical analysis, respectively. The results show that the BaTiO3 powders with the grain size of about 40 nm have a tetragonal crystalline structure at room temperature and a spherical morphology.