This study investigates the role of oxygen vacancy on Fe-doped CeO2
catalyst activity for soot oxidation. The oxygen vacancy was assessed through Ce3+
content. The Fe content was varied between 0 and 30% for two catalyst preparation methods, co-precipitation (CP) and solution combustion synthesis (SCS). X-ray photoelectron spectroscopy indicates that ceria exists as both Ce4+
, while iron is present only as Fe3+
. The catalyst’s activity was evaluated by ignition (T10) and combustion (T50) temperatures using thermogravimetric analysis. Optimum Fe contents yielding the highest activity were found to be 10% and 5% for CP and SCS catalysts, respectively. The surface area and morphology showed a moderate effect on catalyst activity, because catalytic soot oxidation involves solid–solid contact. More importantly, regardless of the fabrication method, it was found that Ce3+
content, which is closely related to oxygen vacancies, plays the most important role in affecting the catalyst activity.
This is an open access article distributed under the Creative Commons Attribution License
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited