Ni/CeO2 catalysts for low‐temperature CO2 methanation: Identifying effect of support morphology and oxygen vacancy

Abstract

AbstractIn order to investigate the effect of support morphology and oxygen vacancy on the low temperature catalytic activity of Ni‐based catalyst for CO2 methanation, three Ni/CeO2 catalysts were prepared by impregnation method, in which CeO2 materials with different morphology of flowerlike, nanowire, and bulk were used. The characterization results showed that the morphology of CeO2 exhibited a significant effect on the preferential exposed crystal planes, which led to the change of oxygen vacancy concentration and metal dispersion, resulting in the enhancement of catalytic activity at low temperature. Among all catalysts, the nanowire‐like Ni/CeO2 catalyst (Ni/W) showed the highest CO2 conversion due to its enhanced oxygen vacancy concentration and CO2 adsorption capacity of the catalyst. In situ DRIFTS experiment showed that the intermediate product of Ni/W catalyst reaction route was formate. In a 100 h–400°C–lifetime test, Ni/W catalyst also showed excellent long‐term stability. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.