New Class of Catalysts Convert CO2 to Hydrocarbons at High Current Density

One of the primary challenges associated with electrochemical carbon dioxide reduction reaction (eCO₂RR) is the need to employ an active catalyst able to produce hydrocarbons that exhibit a high current density and a relatively low overpotential.

A recent study published in Nature Communications by Professor Asadi and his research team at Illinois Tech showcased a new class of catalysts able to effectively convert CO₂ to a range of hydrocarbons, including ethylene (C₂H₄), methane (CH₄), methanol (CH₃OH) and ethanol (C₂H₅OH).

These resulting hydrocarbons displayed exceptionally high current density (reaction rate) and faradaic efficiency (selectivity), demonstrating better performance than gold in terms of activity and better performance than copper in terms of selectivity. Both gold and copper are regarded as state-of-the-art catalysts for eCO₂RR.
 The CO₂ partial pressure as a function of potential and corresponding LSV result (inset) are shown for W₂C nanoflakes as the catalyst for eCO₂RR. Image Credit: Hiden Analytical

Professor Asadi and his team have developed a zero-gap flow electrolyzer for eCO₂RR. This electrolyzer uses di-tungsten carbide (W₂C) nanoflakes as the cathode catalyst and is able to deliver long-term stability of 700 hours, a current density of 548.89 mA/cm² at 2.3 V, and CH₄ selectivity of 82.7.

Real-time differential electrochemical mass spectroscopy (Hiden Analytcial HPR-40-DEMS) was used to confirm a CO₂RR onset potential of 12.7 mV.

A combined computational and experimental study was conducted in collaboration with scientists at Molecular Foundry, Lawrence Berkeley National Laboratory.

This study highlighted that the superior electrocatalytic performance of the W₂C catalyst led to almost spontaneous chemisorption of CO₂ and cleavage of the C-O bond at the tungsten surface atoms.

References

1. “Gold-like activity copper-like selectivity of heteroatomic transition metal carbides for electrocatalytic carbon dioxide reduction reaction” Nature Communications (2021) 12, 5067 doi.org/10.1038/s41467- 021-25295-y

Acknowledgments

Produced from materials originally authored by Mohammad Asadi from the Department of Chemical and Biological Engineering, Illinois Institute of Technology.

This information has been sourced, reviewed and adapted from materials provided by Hiden Analytical.

For more information on this source, please visit Hiden Analytical.