New Opportunity for Carbon‐Supported Ni‐based Electrocatalysts: Gas‐Phase CO2 Methanation

The cost‐effectiveness and excellent performance of conductive‐carbon‐supported Ni‐based electrocatalysts make them attractive materials for hydrogen oxidation and evolution reactions. However, they were previously unused in gas‐phase hydrogenation reactions. In this work, we have expanded the applicability of commercially available advanced Ni/C, NiMo/C and NiRe/C materials from electrocatalysis to heterogeneous catalysis of CO2 methanation. Our catalytic testing efforts indicate that the monometallic Ni/C material demonstrates the best CO2 methanation properties, achieving an excellent CO2 conversion of 83 % at 400 °C with nearly complete selectivity to CH4 of 99.7 %, plus exhibiting intact performance during 90 h of time‐on‐stream testing. Such catalytic properties are among the highest reported to date among carbon‐supported Ni‐based methanation catalysts. Excellent performance of Ni/C stems from the good dispersion of the Ni nanoparticles over N‐containing carbon support material. Supported nanoparticles: A new application for commercially available electrocatalysts was found in the heterogeneous methanation of CO2. A Ni/C catalyst achieved excellent performance, maintaining its activity over 90 h under reaction conditions. The bimetallic counterparts, NiMo/C and NiRe/C also exhibited good performance, although with lower conversion and, in the case of NiMo/C, lower stability. The study presents a new opportunity for the use of these materials.