The effect of Ta2O5- and ZnO-doping on the Curie temperature of BaTiO3

The phase, microstructure and Curie temperature of Ba1-2xTa2xTi1-xZnxO3 (0.005 <= x < 0.1) have been investigated in an attempt to widen its temperature stable region. The compositions formed dense, single-phase, fine-grained BaTiO3 ceramics at x <= 0.01 and multiphase ceramics at x >= 0.015. The dielectric constant decreased with an increase in the dopant concentration due to second phase formation. The Curie temperature increased from similar to 123 degrees C at x = 0.005 to similar to 148 degrees C at x = 0.1 and the optimum sintering temperature decreased from similar to 1430 degrees C at x = 0.005 to 1276 degrees C at x = 0.1.