Effect of calcination temperature on structural and terahertz characterization of M-type barium ferrite

Abstract

We present detailed studies on M-type barium ferrite (BaFe12O19, BaM) synthesized by the sol-gel combustion method that is calcined at 1000 °C, 1100 °C, and 1200 °C. In addition to the structural properties, we present the THz optical dielectric constant and conductivity response of this system as a function of calcination temperature. From x-ray diffraction (XRD) studies, a single-phase of the hexagonal structure is established, and the crystallite size (Dhkl) was calculated to be in the range of 26 nm-28.54 nm. The XRD patterns were analyzed to evaluate lattice parameters (a, c, V) and x-ray density (ρx). Home built terahertz time-domain spectroscopy was performed to investigate the complex refractive index (ns) of the samples at room temperature in a frequency range of 0.2 THz-1.2 THz. The complex dielectric constant (ϵs) and conductivity (σs) as a function of calcination temperature were deduced using THz spectroscopy data. The complex dielectric constant and conductivity of BaM were determined for the calcination temperatures of 1000 °C, 1100 °C, and 1200 °C.