CeCoOx/AC catalysts with synergistic effect for toluene catalytic oxidation: Insights into the contribution of lattice oxygen content and superior oxygen mobility

A series of CeCoO x /AC catalysts using leather waste based activated carbon as the carrier were prepared by a modified impregnation method, and the catalytic performance of toluene oxidation was investigated. Among them, Ce 3.5 Co 3.5 AC catalyst with Ce and Co loading being both 3.5 wt% exhibited the optimal catalytic activity (T 90 = 246 degree celsius). SEM (Scanning Electron Microscope), Raman, XRD (X-ray Diffraction), H 2 -TPR (Hydrogen Temperature Programmed Reduction), O 2 -TPD (Oxygen Temperature Programmed Desorption) and XPS (X-ray Photoelectron Spectroscopy) characterization results revealed that there is interaction between Ce and Co, leading to improved redox ability and oxygen mobility, more oxygen vacancies and lattice oxygen, higher Ce 3 + / Ce 4 + and Co 3 + /Co 2 + ratio, multi -factorial synergies which are positively responsible for its superior catalytic activity. Additionally, the in situ DRIFTS results on Ce 3.5 Co 3.5 AC catalyst verified that benzyl alcohol, benzoate are the main intermediates. Meanwhile, Ce 3.5 Co 3.5 AC catalyst has good resistance ability to water (10 Vol%) and catalytic stability, which has the potential to be applied in practice.