Study of magnetic behaviour of Fe-doped SnO2 powders prepared by chemical method

Rutile Fe-doped SnO2 nanocrystal powders are prepared by a chemical route. The structure of the powders, Sn1−xFexO2 (x = 0, 0.11, 0.14 and 0.20), was rutile with no presence of secondary phases indicating a good dilution of iron in the SnO2 lattice. The cell volume and crystallite size decrease when the Fe content increases. Mössbauer spectroscopy does not reveal any magnetic interactions, only paramagnetic ones with Fe in 3+ oxidation state. Magnetic measurements also show that the samples are mainly paramagnetic at room temperature. At low temperature, two kinds of magnetic species can be distinguished: isolated paramagnetic Fe3+ ions and antiferromagnetically coupled Fe3+ ions. The strength of antiferromagnetic interaction increases when the dopant concentration increases.