Ni/CeO<sub>2</sub> catalysts for low‐temperature CO<sub>2</sub> methanation: Identifying effect of support morphology and oxygen vacancy
Yang Zhang, Tengfei Zhang, Fang Wang, Quanhong Zhu, Qing Liu
Abstract
Abstract In order to investigate the effect of support morphology and oxygen vacancy on the low temperature catalytic activity of Ni‐based catalyst for CO 2 methanation, three Ni/CeO 2 catalysts were prepared by impregnation method, in which CeO 2 materials with different morphology of flowerlike, nanowire, and bulk were used. The characterization results showed that the morphology of CeO 2 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/CeO 2 catalyst (Ni/W) showed the highest CO 2 conversion due to its enhanced oxygen vacancy concentration and CO 2 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.