Enhanced dielectric relaxation behavior of Zr doped Ba0.9Ca0.1ZrxTi1-xO3-0.03Bi3+ ceramics

The enhancement of dielectric relaxation behavior of lead-free Zr4+ doped Ba0.9Ca0.1ZrxTi1-xO3-0.03Bi(3+) ceramics prepared by hydrothermal method were studied. The XRD patterns and calculated lattice parameters both indicated a phase transition from tetragonal to cubic phase with x increasing from 0.00 to 0.12. And the increasing Zr exhibits the homogenization of grain size from SEM patterns. Compositions of x = 0.00 and 0.03 were normal ferroelectrics with sharp T-m peak while the samples exhibit strong relaxation behavior at x = 0.09 and 0.12 and the relaxation parameters were calculated. Thus the lead-free Ba1-xCaxTi1-xZrxO3 system relaxor ferroelectrics were obtained. The P-E loops of all these samples can be divided into two types: the broad and the narrow, which was probably attributed to the grain size and phase transition at room temperature.