Low dielectric loss of Bi-doped BaZr_0.15Ti_0.85O₃ ceramics for high-voltage capacitor applications

BaZr_0.15Ti_0.85O₃ ceramics are prepared via the conventional solid state reaction method. The effects of Bi₂O₃·3TiO₂ doped on dielectric properties and breakdown strength of BaZr_0.15Ti_0.85O₃ ceramics are systematically discussed. Doping of Bi₂O₃·3TiO₂ can obviously improve the breakdown strength and reduce the dielectric loss of the material. It is attributed to the Bi³⁺ substituted Ba²⁺ is an unequal ion substitution, and two Bi³⁺ substitute three Ba²⁺ to produce an A vacancy, thereby increasing the lattice energy and promoting the diffusion and migration of the particles during the sintering process, promoting the sintering and reducing the sintering temperature. However, the dielectric constant of the material is decreased. When the amount of Bi₂O₃·3TiO₂ is 12 mol%, the minimum dielectric loss tanδ = 0.0009, the maximum breakdown strength is E_b = 15.09 kV/mm, the insulation resistivity is 3.52 × 10¹¹ Ω cm. The energy storage density of the BaZr_0.15Ti_0.85O₃ ceramic samples doped with Bi₂O₃·3TiO₂ varies from 0.008 J/cm³ to 0.012 J/cm³.