Synthesis and properties of V2O3-Fe2O3 magnetic ceramic nanostructures

xV(2)O(3)center dot(1-x)Fe2O3 (x=0.1, 0.3, 0.5, and 0.7) solid solutions were successfully synthesized by mechanochemical activation of V2O3 and alpha-Fe2O3 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 xV(2)O(3)center dot(1-x)Fe2O3 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 V2O3-alpha-Fe2O3 composites varies with the ball-milling time due to the effect of V3+-Fe3+ 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 V2O3-alpha-Fe2O3 solid solution had semiconductor properties. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.