Hydrothermal preparation and characterization of ultra-fine BaTiO3 powders from amorphous peroxo-hydroxide precursor

Ultra-fine BaTiO3 powders were hydrothermally prepared by using Ba.Ti-peroxo-hydroxide precursor. Amorphous Ba.Ti-peroxo-hydroxide precursor were prepared by coprecipitation of Ba(NO3)(2) and TiCl4 aqueous solution adding in NH4OH aqueous solution. The phase-pure BaTiO3 powders with a cubic perovskite structure were synthesized at temperature as low as 110degreesC and in the pH range of 10-12. This processing method provides a simple low temperature route for producing BaTiO3 nanoparticles. Under a TEM image and a SAD pattern analysis, it is evident that BaTiO3 powders had spherical shape and single crystal nature. The BaTiO3 ceramic sintered at 1200degreesC for 1 h had 97% of theoretical density and a relatively high dielectric constant (E-r = 3500).