Effect of CO2O3 doping on the dielectric and tunable properties of Ba0.6Sr0.4TiO3 ceramics

Co2O3-doped Ba0.6Sr0.4TiO3 ceramics were fabricated by the traditional fabrication technique and their structural, surface morphological, dielectric and tunable properties were investigated. X-ray diffraction (XRD) studies revealed that all the specimens exhibited a perovskite structure without the existence of the second phase; A strong correlation was observed between the average grain size and Co2O3 doping concentration and the results indicate that Co3+ behaves like a grain-growth inhibitor. The addition of Co2O3 lowers the dielectric constant and the Curie temperature as well. Both the dielectric loss and tunable properties were modified by the addition of Co2O3. When the doping content is up to 2 wt%, the tunability is 14.5% while the dielectric constant decreases from 3000 to 1795.