Synthesis and properties of V2O3–Fe2O3 magnetic ceramic nanostructures

Abstract

Abstract x V 2 O 3 ·(1− x )Fe 2 O 3 ( x =0.1, 0.3, 0.5, and 0.7) solid solutions were successfully synthesized by mechanochemical activation of V 2 O 3 and α-Fe 2 O 3 mixtures. The study aims at exploring the formation of solid solutions at the nanoscale, which is of crucial importance for catalysis and sensing applications. X-ray powder diffraction (XRD), Mossbauer spectroscopy, scanning electron microscopy (SEM), simultaneous differential scanning calorimetry and thermogravimetric analysis (DSC–TGA), and optical diffuse reflectance spectroscopy were combined for detailed studies of phase evolution of x V 2 O 3 ·(1− x )Fe 2 O 3 solid solution under the mechanochemical activation process. The Mossbauer studies indicated that the spectrum of the mechanochemically activated composites evolved from a sextet for hematite to sextets and a doublet upon duration of the milling process with vanadium oxide. Simultaneous DSC–TGA studies indicated that the thermal stability of V 2 O 3 -α-Fe 2 O 3 composites varies with the ball-milling time due to the effect of V 3+ –Fe 3+ ion substitution and the continuous formation of a solid solution. SEM images of the formed solid solution confirmed the wide range distribution of particles sizes composed of nano-grains. Optical diffuse reflectance spectroscopy studies showed that the synthesized V 2 O 3 -α-Fe 2 O 3 solid solution had semiconductor properties.