Moessbauer studies and magnetic properties of SnO2 doped with 57Fe

Transparent conducting SnO2 powders doped with 10% Fe content were prepared by a polymerized complex method under acidic solutions, and annealed finally at 550 deg. C, and at 600 deg. C. These samples were characterized by X-ray diffraction, magnetization, and Moessbauer spectrometry at room temperature. Rutile SnO2 phase was obtained for both samples, and the crystallite sizes were in the range of 13-14 nm. Both samples exhibit magnetization and the saturation magnetization was smaller for the sample annealed at 600 deg. C than for sample annealed at 550 deg. C. Room temperature Moessbauer spectra for both samples showed the presence of two different paramagnetic iron sites but no magnetic sextets. These results suggest that ferromagnetism originates from magnetic defects and not directly from iron ions