Influence of Zirconium and Strontium co-doping on microstructure and dielectric properties of CaCu3Ti4O12 synthesized by the sol-gel method

In this work, Ca1-xSrxCu3Ti4-yZryO12 (X= 0, 0.1; Y= 0, 0.04) ceramics were synthesized by sol-gel method. The result shows that the sample Ca0.9Sr0.1Cu3Ti3.96Zr0.04O12 exhibits a relatively high dielectric constant at room temperature over the frequency range of 10-10(6) Hz(epsilon(r) >13574), and also presents a lower dielectric loss of 0.026. Moreover, the experimental data suggests that the grain size, porosity and the resistance of grain boundary of the CCTO ceramics changed with the variety of doping ions are the main factor affecting dielectric properties. Meanwhile, the nonlinear coefficient values were improved, so as the breakdown electric field. Our results indicate that the Sr/Zr co-doped CCTO is considered as a good candidate to be used in fabricating microelectronic and memory devices with its higher epsilon(r), lower tan delta, and better nonlinear characteristics.