Nanosized Tetragonal BaTiO3 Powders Synthesized by a New Peroxo-Precursor Decomposition Method

A new peroxo-precursor decomposition method is developed for synthesis of BaTiO3. Peroxopolytitanic acid solution is prepared by reaction between metallic titanium powder and H2O2 aq, and the amorphous peroxo-precursor is prepared by mixing the peroxo-polytitanic acid with Ba(OH)(2) aq. The reaction time between the metallic titanium powder and H2O2 aq is shortened from 72 to 6 h by increasing the concentration of H2O2 aq from 30 to 70 wt % BaTiO3 with crystallite size of 14.7-419.7 nm and tetragonality c/a of 1.0037-1.0090 is obtained by heating the precursor for 1 h at 600-1150 degrees C in air. BaTiO3 obtained at 650 degrees C shows a uniform size distribution in the field-emission scanning electron microscope (FE-SEM) image around 30 nm, and the dielectric constant of 360.