Synergistic Electrocatalytic Syngas Production from Carbon Dioxide by Bi‐Metallic Atomically Dispersed Catalysts

The production of syngas by traditional processes such as steam methane reforming is energetically intensive and produces a large amount of CO2 emissions. In contrast, the electrochemical CO2 reduction reaction (CO2RR) enables the carbon neutral production of syngas at ambient conditions. Among non-precious metal catalysts, metal-nitrogen-carbon electrocatalysts are inexpensive and highly selective towards syngas production. This study examined the selectivity of mono- and bi-metallic (M-N-C, M=Fe, Mo or FeMo) electrocatalysts towards syngas production. The ratio of the CO : H-2 in the syngas was tuned by modifying the ratio of the metallic precursors in the bi-metallic FeMo-N-C catalysts, tailoring the catalysts' selectivity towards the CO2RR or the hydrogen evolution reaction (HER). The catalyst synthesis temperature(s) were considered as they influence the catalyst morphology and activity. Further, the dependence of the ratio of CO : H-2 in the syngas as a function of the potential was explored for the different bi-metallic catalysts. This work showed that by tailoring both the ratio of Fe : Mo in the bi-metallic catalyst and optimizing the reductive potential, a CO : H-2 ratio between 0.25 to 5 was achievable. This study demonstrated a novel approach in which the ratio of the product syngas composition could be tailored in a single reaction, without the need for further downstream processing to reach a desired composition.