The magnetic and structural properties of hydrothermal-synthesized single-crystal Sn1−xFexO2 nanograins

The crystal structure and magnetic properties of Sn1−xFexO2 nanograins synthesized by simple hydrothermal method using SnCl4·5H2O and FeCl3·6H2O as raw materials are studied. No secondary phase was found in the XRD spectrum. The linear change of lattice volume for different Fe content strongly supports that the Fe3+ substitutes Sn4+ in SnO2 lattice. A Raman and IR spectra study indicated that the Fe incorporates into the SnO2 lattice. Both ferromagnetic and paramagnetic signals are detected in the Mössbauer spectra. The Sn1−xFexO2 (x⩽0.10) samples show room-temperature ferromagnetism (RTFM) and the saturation magnetization increased with increasing Fe percent. Fe ions present three kinds of magnetic behaviors including paramagnetic, ferromagnetic, and antiferromagnetic in the samples observed by investigation of the M–H and M–T curves. The weak RTFM was due to only a fraction of Fe ions contributing to magnetic-order coupling mediated by oxygen vacancy.