Molybdenum carbide as alternative catalysts to precious metals for highly selective reduction of CO₂ to CO

Rising atmospheric CO₂ is expected to have negative effects on the global environment from its role in climate change and ocean acidification. Utilizing CO₂ as a feedstock to make valuable chemicals is potentially more desirable than sequestration. A substantial reduction of CO₂ levels requires a large-scale CO₂ catalytic conversion process, which in turn requires the discovery of low-cost catalysts. Results from the current study demonstrate the feasibility of using the non-precious metal material molybdenum carbide (Mo₂C) as an active and selective catalyst for CO₂ conversion by H₂. Active, selective, and cheap: Mo₂C and cobalt-modified Mo₂C were both shown to be effective catalysts for CO₂ conversion by hydrogen in flow reactor experiments over powder catalysts. In-situ XANES measurements verified that Mo₂C can undergo an oxidation-carburization cycle. Modifying Mo ₂C with small amounts of cobalt further improved catalytic performance.