High methane combustion activity of PdO/CeO2–ZrO2–NiO/γ-Al2O3 catalysts

• NiO was dissolved into the CeO2–ZrO2 lattice to enhance the reducibility of the catalyst.
• PdO/CZNi/Al2O3 possessed high oxygen storage and release abilities.
• PdO/CZNi/Al2O3 exhibited the highest methane conversion at 300 °C.

PdO/CeO2–ZrO2–NiO/γ-Al2O3 catalysts were prepared for the combustion of methane at moderate temperatures. The introduction of a small amount of NiO within the cubic fluorite CeO2–ZrO2 structure as a promoter effectively enhanced the oxygen release and storage abilities of the catalysts, thereby achieving the complete oxidation of methane. The catalyst with the highest activity for methane combustion was 11.3 mass% PdO/20 mass% Ce0.64Zr0.16Ni0.2O1.9/γ-Al2O3, and efficient combustion was realized at a temperature as low as 300 °C.