Characterization and Synthesis of Additive Coated BaTiO3 Nano-Powder

Abstract

Two different BaTiO3 (160nm) nanopowders coated with Y and with Dy were fabricated by an aqueous chemical coating method, and their dielectric properties and microstructures were investigated with X-ray diffraction, Impedance analyzer, SEM and TEM. Y and Dy were coated on the BaTiO3 powder using nitrates. Coated BaTiO3 powders were pressed in a disk shape and sintered at 1150~1200°C for 2 hours in reduced atmosphere of 10%H2 - 90%N2. Coating layer of the BaTiO3 particle was thin with a thickness of 3 ~ 5nm. Coated BaTiO3 sintered sample exhibited a larger lattice parameter (a, c) and smaller tetragonality (c/a) than pure BaTiO3 one. Y coated BaTiO3 sample sintered at 1200°C showed good dielectric properties with a high dielectric constant of around 2000 and a stable temperature coefficient of capacitance (TCC).