Preparation and Characterization of Room Temperature Ferromagnetic Co-Doped Anatase TiO₂ Nanobelts

Abstract

We herein report a preparation process of Co-doped anatase TiO2 nanobelts facilely combining ion-exchange with hydrothermal treatment. A series of TiO2 materials with different Co2+ contents were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Fourier transform infrared (FT-IR), and magnetic measurement techniques. The results show that Co2+ cations have doped into the TiO2 lattice structure and that any metallic cobalt clusters or nanoparticles could not be found. The magnetic result demonstrates that the prepared Co-doped TiO2 samples are room-temperature ferromagnetic materials, whereas with the increase of Co2+ content, the remnant magnetization tends to decrease due to the superexchange coupling interaction between Co2+ ions owing to the ununiform distribution.