Enhancement of breakdown electric field and dielectric properties of CaCu3Ti4O12 ceramics by Sr doping

In order to enhance the breakdown electric field (E-b) and dielectric properties of CaCu3Ti4O12 ceramics, Ca1xSrxCu3Ti4O12 ceramics with different Sr doping concentration were fabricated by modified sol-gel method. It was found that the dielectric properties of Ca1-xSrxCu3Ti4O12 ceramics greatly depended on the Sr doping concentration, and Ca0.5Sr05Cu3Ti4O12 ceramics behaved high E-b of similar to 52.50 kV/cm, low dielectric loss (tan delta) of similar to 0.066, and high dielectric constant (epsilon'(r)) of similar to 3902 at 1 kHz and room temperature, simultaneously. Moreover, it was proved that the enhanced Eb can be attributed to both the increasing amount of grain boundaries and higher Schottky barrier height. All the 'results indicated that Ca0.5Sr0.5Cu3Ti4O12 ceramics were very promising materials for practical applications.