Affiliation: | 1. National Synchrotron Radiation Laboratory, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui, 230029 China;2. School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798 Singapore These authors contributed equally to this work.;3. Department of Chemical Engineering, Columbia University, New York, NY, 10027 USA;4. Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973 USA;5. Department of Physics, Florida A&M University, Tallahassee, FL, 32307 USA |
Abstract: | The electrochemical CO2 reduction reaction (CO2RR) to yield synthesis gas (syngas, CO and H2) has been considered as a promising method to realize the net reduction in CO2 emission. However, it is challenging to balance the CO2RR activity and the CO/H2 ratio. To address this issue, nitrogen-doped carbon supported single-atom catalysts are designed as electrocatalysts to produce syngas from CO2RR. While Co and Ni single-atom catalysts are selective in producing H2 and CO, respectively, electrocatalysts containing both Co and Ni show a high syngas evolution (total current >74 mA cm−2) with CO/H2 ratios (0.23–2.26) that are suitable for typical downstream thermochemical reactions. Density functional theory calculations provide insights into the key intermediates on Co and Ni single-atom configurations for the H2 and CO evolution. The results present a useful case on how non-precious transition metal species can maintain high CO2RR activity with tunable CO/H2 ratios. |