Structural and temperature dependent dielectric behaviour of B_xFe_(3−x)O₄ nanoferrite particles

Abstract

The auto‐combustion technique was employed to synthesize nano particles of BxFe(3−x)O4 (x = 0.0, 0.7, 1.18, 1.36 and 1.54). The resulting structural and dielectric properties of the boron doped Fe3O4 were evaluated. XRD analysis confirmed the presence of a single spinel structure with crystallite dimensions ranging from 21.18 to 26.43 nm and lattice parameters of 8.211 to 8.487 Ǻ. The morphological images revealed homogenous and spherical grain sizes, while EDX confirmed the presence of constituent elements used. The X‐ray density increased whereas the bulk density and the porosity decreased with boron substitution. The study of dielectric properties and AC conductivity (σAC) was demonstrated and the AC conductivity decreased with increasing boron concentration, indicating a hopping mechanism. Moreover, noticeable variations in dielectric loss, AC conductivity, and dielectric permittivity with temperature and frequency were observed. These observations were attributed to the Maxwell–Wagner interfacial polarization and the hopping of charges between Fe3+ and Fe2+ ions.