Enhanced dielectric properties and sinterability of CaCu3Ti4O12 ceramics by Sr2+ doping

CaCu3Ti4O12 ceramics substituted by Sr2+ for Ca2+ were prepared by the solid state reaction method. It was found that Sr2+ substitution increased the lattice constant of CaCu3Ti4O12 in a consistent manner. The dielectric properties, sinterability, and microstructures of the Ca1−xSrxCu3Ti4O12 ceramics were investigated. Large enhancement of dielectric properties (increase in dielectric constants and decrease in dielectric losses) was observed in the Ca1−xSrxCu3Ti4O12 ceramics at x=0.2 within the frequency range between 0.2 and 20 kHz. It was found that the doping of Sr2+ greatly improved the sinterability of Ca1−xSrxCu3Ti4O12 ceramics by largely reducing sintering temperature and promoting densification and grain growth during sintering.