Study of structural, infrared, frequency dependent dielectric and ferroelectric properties of Fe substituted BST ceramics

Barium Strontium Titanate (BST) ceramics with iron substitution, represented by chemical composition Ba0.90Sr0.10Ti1-3x/4FexO3 (x = 0.000 and 0.005) were prepared by traditional solid-state reaction approach. The X-ray diffraction (XRD) analysis indicated that the ceramics exhibit a single perovskite phase characterized by a tetragonal structure. As the ferroelectricity in perovskites depends on the vibration of the crystal lattice, Fourier Transform Infrared Spectroscopy (FTIR) analysis was also conducted. FTIR spectra depicted strong peaks representing TiO6 octahedral vibration for both the samples. Dielectric measurements (dielectric constant (ε) and tangent loss (tanδ)) were conducted over a frequency range of 1 kHz–-1 MHz at room temperature. Additionally, ferroelectric hysteresis loops (P-E loops) were recorded at different frequencies. It was observed that as the frequency increased, both remnant polarization (Pr) and coercive field (Ec) exhibited a decreasing trend for both the samples.