Fe-doped SnO 2 nanopowders obtained by sol–gel and mechanochemical alloying with and without thermal treatment

Abstract

The present work is aimed to compare the physical properties of Sn 1−x Fe x O 2−δ (x = 0, and 0.05) nanopowders obtained by sol-gel method, mechanochemical alloying, and mechanochemical alloying followed by thermal treatment. The X-ray diffraction of Sn 1−x Fe x O 2−δ samples prepared by sol-gel showed peaks due to the cassiterite phase of SnO 2 and their Mössbauer spectra showed ferromagnetic and paramagnetic signals. The samples obtained by the milling process of SnO 2 mixed with α-Fe showed Bragg peaks due to SnO 2 (rutile) with a line broadening caused by the reduction of grain sizes and the presence of microstrains. Mössbauer spectra for these samples revealed the presence of Fe 3+ as well as unreacted α-Fe. In the case of mechanochemical alloying with thermal treatment, the incorporation of Fe 3+ in the SnO 2 structure with the presence of impurities was observed.