Investigations of Impedance Properties of Calcium Copper Titanate (CaCu3Ti4O12) Ceramic

CaCu3Ti4O12 (CCTO) is synthesized by solid-state route at a sintering temperature of 1100 °C for 4 h. Crystal structure and microstructural analysis are performed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM), respectively. XRD confirms the single phase CCTO with cubic crystal structure having Im3 space group. FE-SEM reveals the distribution of dense grains with minimum porosity. The average grain size is obtained at around ∼ 1.67 μm. The permittivity of synthesized CCTO ceramic is ∼ 8099, and tangent loss is ∼ 0.73 at 30 °C and 100 Hz. The activation energy of 0.11 eV is estimated from conductivity analysis. Positive temperature coefficient resistance (PTCR) behaviour is confirmed by impedance analysis. Contribution of grain and grain boundary on the impedance properties is explained by Nyquist analysis. Due to high dielectric constant and low dissipation factor along with good thermal stability, this material is a good candidate for energy storage devices. The CV plot confirms the capacitive behaviour of CCTO ceramic.