EFFECT OF Co₃O₄ NANOPARTICLE ON THE PROPERTY OF BARIUM TITANATE CERAMIC

Abstract

Effects of the Co3O4 nanoparticle on the phase formation, microstructure and dielectric properties of barium titanate ceramics are investigated in this study. Co3O4 -doped BaTiO3 ceramics were prepared by the conventional mixed oxide method followed by normal sintering in air. Systematic studies of X-ray diffraction (XRD), scanning electron microscopy and dielectric spectroscopy with varying doping levels were performed. The cell parameters, tetragonality and crystallite size of doped ceramics also were calculated from XRD data. Results showed that the single phase of BaTiO3 gave no evidence of unwanted peak forms in any of the samples. Cubic phase occurred after adding Co3O4 at 0.25 mol%. Various grain sizes and shapes were found in this system. Finally, adding Co3O4 in BaTiO3 ceramics resulted in shifting of the Curie point to a lower temperature. The composition, x = 0.25, showed different dielectric behavior, which related to appearance of the cubic phase and fine grain microstructure.

Effect of Cobalt substitution on the structural, electrical and magnetic properties of BaTiO<inf>3</inf> ceramics

“…In this situation, when Co-ion replaces the Ti-ion, it may either expand the unit cell or suppress it [13]. Both Co 2+ as well as Co 3+ ions can substitute for Ti site [14] and BTO ceramic is expected to lose oxygen due to cobalt substitution. At the low Co concentration, BTO does not have enough oxygen vacancies for a full transition from tetragonal to the hexagonal phase [1,14].…”

“…Both Co 2+ as well as Co 3+ ions can substitute for Ti site [14] and BTO ceramic is expected to lose oxygen due to cobalt substitution. At the low Co concentration, BTO does not have enough oxygen vacancies for a full transition from tetragonal to the hexagonal phase [1,14]. As the Co concentration increases, the amount of oxygen vacancies increase, which influence on the hexagonal phase.…”