Influence of annealing temperature on microstructural and magnetic properties of Fe2O3 nanoparticles synthesized via sol-gel method.

Using ferric nitrate Fe(NO3)3 9H2O as a precursor and Ethylene Glycol monoethylene ether as a solvent, Fe2O3 NPs were prepared using the sol-gel technique. X-ray diffraction (XRD) study of Fe2O3 NPs at different calcination temperatures to determine the size of the crystallite was performed using various methods of calculation showed that crystallite size enhanced to the presence of single phase (γ-Fe2O3) at lower temperature, as the contribution of other phase (α-Fe2O3) increases in size varies, but again begins to decrease as the material converts to single phase. The average crystallite size of the Fe2O3 NPs was 7–11 nm. The synthesized Fe2O3 NPs are spherical in shape, according to FE-SEM analysis. The EDX and FTIR spectra of the synthesized particles revealed that they are pure Fe2O3 nanoparticles. The magnetic properties of synthesized nanoparticle such as saturation magnetization (Ms) and coercivity (Oe) are calculated from hysteresis curve obtained from Vibrating-sample magnetometer (VSM) data demonstrate that the sample belong to magnetically soft iron oxides and possess a multi-domain structure. The Mössbauer spectral analysis revealed the relative fraction of γ-Fe2O3 was more at lower temperature but relative fraction for α-Fe2O3 increases as temperature increases which is in quite agreement with structural data. [ABSTRACT FROM AUTHOR]