Improved Activity of Ru/CeO<sub>2</sub> Catalyst for CO<sub>2</sub> Methanation by Enhanced Electronic Metal–Support Interaction
Mengxing Li, Weiwen Yan, Menghui Liu, Changjun Liu
Abstract
The Ru-based catalyst for CO 2 methanation has drawn increasing attention. In this work, plasma decomposition of the precursor of the Ru/CeO 2 catalyst was conducted at atmospheric pressure and approximately 150 °C, followed by thermal hydrogen reduction at 200 °C. The obtained catalyst possesses more basic sites and oxygen vacancies, which promote the adsorption and activation of CO 2 . A high Ru dispersion is also achieved with a charge transfer from oxygen vacancy to dispersed Ru nanoparticles, causing enhanced electronic metal–support interaction and an active Ru/CeO 2 interface. The dissociative adsorption of H 2 is thus accelerated. The formate and CO pathways are all promoted for CO 2 methanation. An improved low-temperature performance for the methanation of CO 2 was thereby attained. For example, a CO 2 conversion of 85.2% with a methane selectivity of 99.0% was achieved on the plasma decomposed catalyst at 300 °C with a feed gas of CO 2 /H 2 /N 2 of 16/64/20 at 60,000 mL·g cat –1 ·h –1 .