Improved\nActivity of Ru/CeO<sub>2</sub> Catalyst for\nCO<sub>2</sub> Methanation by Enhanced Electronic Metal–Support\nInteraction

The Ru-based catalyst for CO<sub>2</sub> methanation\nhas drawn\nincreasing attention. In this work, plasma decomposition of the precursor\nof the Ru/CeO<sub>2</sub> catalyst was conducted at atmospheric pressure\nand approximately 150 °C, followed by thermal hydrogen reduction\nat 200 °C. The obtained catalyst possesses more basic sites and\noxygen vacancies, which promote the adsorption and activation of CO<sub>2</sub>. A high Ru dispersion is also achieved with a charge transfer\nfrom oxygen vacancy to dispersed Ru nanoparticles, causing enhanced\nelectronic metal–support interaction and an active Ru/CeO<sub>2</sub> interface. The dissociative adsorption of H<sub>2</sub> is\nthus accelerated. The formate and CO pathways are all promoted for\nCO<sub>2</sub> methanation. An improved low-temperature performance\nfor the methanation of CO<sub>2</sub> was thereby attained. For example,\na CO<sub>2</sub> conversion of 85.2% with a methane selectivity of\n99.0% was achieved on the plasma decomposed catalyst at 300 °C\nwith a feed gas of CO<sub>2</sub>/H<sub>2</sub>/N<sub>2</sub> of 16/64/20\nat 60,000 mL·g<sub>cat</sub><sup>–1</sup>·h<sup>–1</sup>.