Exploring the Microwave Assisted Sol-Gel Synthesized (Al, Co) Co-Doped Iron Oxide Thin Films for Detailed Impedance and Magnetodielectric Rsposnse

Materials with remarkable magnetodielectric properties are promising candidates for multifunctional devices. Microwave assisted sol-gel route is used to synthesize iron oxide thin films at microwave power of 720W with variation in Al-Co concentration of 2wt% to 10wt%. XRD analyses confirms the transition of phases from pure maghemite (γ-Fe2O3) to magnetite (Fe3O4) thin films at Al-Co concentrations of 6–10 wt%. Highest saturation magnetization of 610.23emu/cm3 are observed for Fe3O4 respectively at 10wt%. The dielectric constant and tangent loss exhibit the normal dispersion behavior with maximum value of dielectric constant attained at log f=5 is ~455 with low value of tangent loss at dopant concentration of 10 wt%. Maximum magnetodielectric coupling (MDE) is obtained for Fe3O4 thin films at 10wt% Al-Co concentration. As Fe3O4 phase is found to exhibit peculiar MDE coupling with respect to other phases. Thus, the Fe3O4 phase reveals exotic magnteodielectric coupling anomalies