Influence of thermal-treatment effects on the structural and magnetic properties of Sn1-xFexO2 nanopowders produced by mechanical milling

Abstract

In this research work, iron-doped tin dioxide nanoparticles were successfully produced by high-energy ball-milling and their structural and magnetic properties were evaluated by means of room temperature X-ray diffraction, Mössbauer spectroscopy, and vibrating sample magnetometry. In order to evaluate the thermal stability of the compounds, samples were subjected to a thermal treatment and their structural and magnetic properties were studied. The nanoparticles were produced by processing SnO2 commercial powders together with doping amounts of Fe2O3 commercial powder in a high-energy planetary ball-mill. X-ray diffraction showed the presence of a single crystalline structure (that of the host compound) in all samples. Mössbauer spectroscopy confirmed that Fe3+ ions substitute for Sn4+. It was also used to show the disorder induced by the incorporation of iron ions in the structure of the host matrix. Magnetic measurements showed the coexistence of paramagnetism and a weak ferromagnetism. The interaction between singly ionized oxygen vacancies and doping Fe ions is the suggested reason behind the ferromagnetic ordering observed in this research work. The observed ferromagnetism is interpreted in terms of the bound magnetic polaron model and the charge transfer model. The insertion of the transition metal Fe into SnO2 matrix resulted in ferromagnetism at room temperature even at high dopant concentrations.