Synthesis and dielectric properties of calcium copper titanate (CCTO) based ceramics

Abstract

The perovskite CaCu3Ti4O12 (CCTO) powders with various oxide phase impurities were synthesized via citric gel combustion method. Influence of citric acid amount used for gel preparation was examined in order to lower CCTO formation temperature to obtain powders with less impurities and better micro structural characteristics. Prepared powders were pressed into pellets and sintered at 1000 °C. Effects of oxide component impurities, such as CuO, rutile, anatase, CaTiO3 were examined on sintering behavior and dielectric properties of ceramics. Phase composition of powders and sintered specimens were determined by XRD, microstructure powders and sintered bodies were observed by SEM, and dielectric constants of sintered ceramics were measured by Wayne-Kerr B224 universal bridge.