ABSTRACT
Pure tetragonal phase barium titanate nanograin with an average diameter of about 54 nm has been synthesized via a sol-gel route starting from soluble precursors of barium and titanium and without surfactant. The gel was peptized and crystallized in water under a refluxing condition. The effect of pH value on the properties of BaTiO3 powder was investigated. BaTiO3 samples were characterized by X-ray diffraction, BET analysis, transmission electron microscope and thermal gravimetric analysis. It was found that the pH value of solvent had a great influence on the calcination temperature of powders while BaTiO3 crystallites were formed at 800 ºC by acidic catalyst process and at 1000 ºC by using basic additives. Higher initial pH led to smaller crystallite sizes of BaTiO3 powders. As-prepared powder has perovskite tetragonal structure with an average grain size of 54 nm and a high BET value of 25 m2/g for pH = 9. Sol gel route has shown many distinctive advantages in the preparation of high purity BaTiO3 nanopowders without Ba and Ti losses and hazardous wastes.