Structural, spectral, dielectric and magnetic properties of indium substituted copper spinel ferrites synthesized via sol gel technique

Abstract Indium (In) substituted copper ferrites with nominal composition CuInxFe2-xO4 (where 0.00 ≤ x ≤ 0.32) were prepared via sol gel route. Influence of In3+ on thermal, structural, spectral, magnetic and dielectric properties are elucidated. The complete decomposition and stable phase formation was assessed from thermal gravimetric analysis (TGA) and differential thermal gravimetric analysis (DTA). The structure of copper ferrite is single phase estimated from X-ray diffraction (XRD) analysis. Lattice constant (a) and crystallite size first increased then decreased with the inclusion of In3+ ions. Cell volume, X-ray density and bulk density are improved due to substitution of indium ions. Magnetic studies are carried out by vibrating sample magnetometer (VSM). The various magnetic parameters i.e saturation magnetization (Ms), coercivity (Hc) and retentivity (MR) are elucidated. The value of Ms and Hc are reduced with the substitution of In3+ ions. The squareness ratio, anisotropy constant and Bohr's magneton were also decreased as the inclusion of indium concentration. The value of dielectric constant (e′), dielectric loss (e") and tan loss were reduced as frequency increased. The surface morphology was studied by SEM (scanning electron microscopy). The small value of dielectric parameters and coercivity of synthesized ferrites suggested that indium substituted copper ferrites might be useful in switching and high frequency applications.