Facile fabrication of hollow structured Cu-Ce binary oxides and their catalytic properties for toluene combustion

• Hollow structured Cu-Ce binary oxide catalysts were facilely synthesized. • The Cu/Ce components were well tuned, and the Cu 6 Ce 4 O x catalyst showed the best activity. • The synergistic effect is mainly originated from the formed Cu-O-Ce solution. • Large surface area, rich oxygen species and better redox behavior were responsible for superior activity. A series of hollow structured CuCeO x composite catalysts with different Cu/Ce molar ratios were synthesized via a simple hydrothermal approach, which were applied in catalytic combustion of toluene. The XRD and Raman results indicate that partial of Cu ions are incorporated into CeO 2 lattice, forming Cu-O-Ce solid solution. This strengthens the synergistic interaction between CuO and CeO 2 , enhancing the amounts of oxygen vacancies and low-temperature reducibility. Among the serial catalysts, the Cu 6 Ce 4 O x catalyst exhibits superior catalytic performance, and its 90% conversion (T 90 ) is 260 ℃. The high surface area, low-temperature reducibility, and abundant surface active oxygen species are main factors for superior catalytic performance. The DRIFTs result further clarifies the possible pathway for toluene oxidation, that toluene is converted via benzyl alcohol, benzaldehyde, and benzoate species as main intermediates and is finally decomposed to CO 2 and H 2 O.