Ti1-xFexO2 (x = 0.00-0.13) nanoparticle samples were prepared by hydrolysis method. We investigated the effects of Fe doping on the structural and magnetic properties of the Ti1-xFe xO2 nanoparticle system. Scanning electron microscopy and X-ray diffraction measurements confirm that the particle size of the powder is in nanoscale, and that the magnetic Fe impurities substitute for the Ti sites in the anatase TiO2 phase. All the samples with x > 0 were found to be super-paramagnetic at room temperature by magnetization measurements. Raman spectra also strongly support that the Fe atoms go into the Ti-site in the TiO2 structure. For comparison, ceramic Ti1-xFe xO2 samples were also prepared by usual ceramic method. Ferromagnetism was observed only in the ceramic Ti1-xFe xO2 system. Additional Raman peak at around 610 cm -1 is observed only in the ceramic samples. This may be related to the clusters created by mixture of various valence state of Fe, which probably would be the cause for ferromagnetism observed in the ceramic Ti 1-xFexO2 system.
Bibliographical noteFunding Information:
This research was sponsored by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, under contract DE-AC05-00OR22725 with UT-Battelle, LLC, administered by James R. Keiser at the Oak Ridge National Laboratory and supported by in-kind contributions from the following project partners: Åbo Akademi University, Andritz Oy, Babcock & Wilcox, Catalyst Paper, Chalmers University of Technology, Domtar Corp., FM Global, FPInnovations, Foster Wheeler, Georgia Institute of Technology, Haynes International, Howe Sound Pulp & Paper, International Paper, MeadWestvaco, Metso Power, Outokumpu Stainless, Rolled Alloys, Sandvik Materials Technology, SharpConsultant, Southern Company, Special Metals, ThyssenKrupp VDM, University of Toronto Pulp and Paper Centre, Vattenfall Power, and the Weyerhaeuser Co. Particular thanks are also due to John D. Andrews, Jr., (MeadWestvaco) and to D. William Francis (FPInnovations) for helpful comments.
- Raman spectroscopy