Influence of V2O5 on the properties of BaTiO3-Y2O3-MgO ceramics

The microstructure and dielectric properties Of V2O5-doped BaTiO3-Y2O3-MgO ternary system were studied. SEM shows that V ions can promote grain growth of BaTiO3 based ceramics, but decrease the density of sintered ceramics. XRD indicates that V-doped samples have pseudocubic structure and the solubility limit of V is more than 1.0mol% The results show that V can increase the intensity of Curie peak and improve the temperature stability of dielectric constant, because of the formation of core-shell-grains with thin shell layer, which is attributed to the fact that V ions can effectively inhibit the diffusion of Y and/or Mg ions into BaTO3 grains and change the distribution of doping ions in the grains. Moreover multivalent V ions can reinforce the nonreducibility of this system, and the insulation resistivity increases to 10 13 Q-cm and dielectric loss decrease to 0.63% consequently. The high performance materials with dielectric constant of 2600 satisfying the X8R requirement is achieved when 0.1mol% V is added.