Microscopic studies of a SnO2/α-Fe2O3 architectural nanocomposite using Mössbauer spectroscopic and magnetic measurements

A SnO2/α-Fe2O3 architectural nanocomposite, which was evidenced as SnO2 nanorod arrays assembled on the surface of α-Fe2O3 nanotubes in our previous study, was investigated microscopically by means of Mössbauer spectroscopic and magnetic measurements. It was found for the SnO2 nanorods that Fe3+ ions substituted slightly to Sn0.998Fe0.002O2. Concerning the α-Fe2O3 tubes, the Morin transition, which was completely suppressed in the mother, SnO2-free α-Fe2O3 nanotubes, was found to be recovered locally. We speculate that it takes place in the interface area as a result of structural modification needed for the connection with the SnO2 nanorods.