Physicochemical and Redox Characteristics of Fe Ion-doped CeO2 Nanoparticles

We report the structural, thermal, optical, and redox properties of Fe-doped cerium oxide (CeO2) nanoparticles, obtained using the polyol-co-precipitation process. X-ray diffraction data reveal the formation of single-phase structurally isomorphous CeO2. The presence of Fe3+ may act as electron acceptor and/or hole donor, facilitating longer lived charge carrier separation in Fe-doped CeO2 nanoparticles as confirmed by optical band gap energy. The increased content of localized defect states in the ceria gap and corresponding shift of the optical absorption edge towards visible range in Fe-doped samples can significantly improve the optical activity of nanocrystalline ceria. The better-quality redox performances of the Fe-doped CeO2 nanoparticles, compared with undoped CeO2 nanoparticles, were ascribed mainly to a decrease in band gap energy and an increase in specific surface area of the material. As observed from TPR studies all Fe -doped CeO2 nanoparticles, particularly the 10 mol % Fe doped CeO2 nanoproduct, exhibit excellent reduction performance.