Mössbauer spectroscopic investigations of nanophase iron oxides synthesized by thermal plasma route

Abstract Magnetic nanoparticles of iron oxide were synthesized by transferred arc plasma induced gas phase condensation method. Structural, morphological and magnetic studies of the as synthesized powder were carried out using X-ray diffraction, transmission electron microscopy and Mossbauer spectroscopy. These studies have revealed the simultaneous nucleation and condensation of different magnetic phases with a broad size distribution of the nanoparticles which is peaked at 30–50 nm and ranges from 10 nm to 80 nm. 57 Fe Mossbauer spectra recorded at various temperatures (5 K–300 K) in presence of external magnetic field (at 5 K) have suggested the presence of different phases of iron oxide with sizable amounts of γ-Fe 2 O 3 and α-Fe 2 O 3 in addition to Fe 3 O 4 . The relative concentrations of these phases have been obtained by a self consistent spectral area analysis and were found to be 44:22:34 (%).