Structural, thermal, Fe-57 and Eu-151 Mossbauer studies of Eu2O3-Fe2O3 ceramic nanostructures

xEu(2)O(3)-(1-x)alpha-Fe2O3 (x=0.1, 0.3, 0.5, and 0.7) nanoparticle system was successfully synthesized by mechanochemical activation of Eu2O3 and alpha-Fe2O3 mixtures for 0-12 h of ball milling time. The investigations aimed at exploring the formation of magnetic ceramic nanostructures, which are of crucial importance for catalysis and sensing applications. X-ray powder diffraction (XRD),as well as Fe-57 and Eu-151 Mossbauer spectroscopy and thermal analysis by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) was used to study the phase evolution of xEu(2)O(3)-(1-x)alpha-Fe2O3 nanoparticle system under the mechanochemical activation process. Rietveld refinement of the XRD patterns yielded the values of the particle size as a function of composition and milling times and indicated the formation of the EuFeO3 perovskite for large x values and long milling times. The Fe-57 Mossbauer studies showed 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 europium oxide. The Eu-151 Mossbauer investigations showed that the isomer shift decreased with increasing milling time for all molar concentrations employed. These results correlate well with the DSC/TGA analysis, which shows the consumption of hematite and the formation of EuFeO3 in the system under investigation. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.