Fabrication of high-performance Ba0.95Ca0.05Ti0.85Zr0.15O3 ceramics by aqueous chemical coating method

Al2O3-coated Ba0.95Ca0.05Ti0.85Zr0.15O3 dielectric ceramics with excellent performance were fabricated by a novel aqueous chemical coating method. With this method, Al2O3 was well coated on the surface of Ba0.95Ca0.05Ti0.85Zr0.15O3 powders, resulting in homogenous microstructure, excellent dielectric and electrical properties. The specimen with an appropriate coating amount of 0.4 wt% Al2O3 exhibited the most outstanding properties. The dielectric constant at room temperature could reach ~13,600, with low dielectric loss (~0.5%) and high insulation resistivity (~6.2×1011 Ω· cm). DC breakdown strength was also improved to ~12.5 kV/mm because of Al2O3 coating.