Phase Evolution, Microstructure, and Electrical Properties of Ca‐Modified BaTiO 3 Perovskite Ceramic for Capacitor Applications

In this research work, we have examined the influence of calcium substitution on the structural, dielectric response, conduction mechanism, and optical properties of BaTiO 3 (BT) ceramic. The in‐depth investigation shows that when the Ca 2+ cations are incorporated, there are noticeable changes in the parent BT's dielectric constant ( ε ′), dielectric loss ( ε ″), and AC conductivity ( σ ac ). Polycrystalline powders of Ba (1− x ) Ca x TiO 3 (BCT, x = 0.1, 0.2, and 0.3) ceramics were produced by the traditional solid‐state reaction method. X‐ray diffraction and scanning electron microscopy analyses were done for structural studies. The dielectric constant and tangent loss were studied in different temperature and frequency ranges. Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, impedance spectroscopy, and dielectric‐temperature studies provided strong evidence of Ca 2+ substitution at the Ba/Ti sites. The electrical conduction behavior of BCT was studied by impedance spectroscopy. The AC conductivity was investigated and described by Jonscher's law. The AC conductivity is found to increase with the increase in Ca content due to the small polaron hopping conduction mechanism between the Ca and Ba ions. NSPT and CBH models were employed to explain the conduction processes in the materials. This study demonstrates effective modifications in structural and dielectric properties, as well as conductivity, through the controlled incorporation of Ca into BT.