|
|||||
|
|
Sulfur Changes the Electrochemical CO2 Reduction Pathway over Cu Electrocatalysts |
|
| Authors: | Shuyu Liang Jiewen Xiao Tianyu Zhang Yue Zheng Qiang Wang Bin Liu |
| Affiliation: | 1. Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083 P. R. China Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083 P. R. China School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459 Singapore These authors contributed equally to this work.;2. Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083 P. R. China Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083 P. R. China These authors contributed equally to this work.;3. Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083 P. R. China;4. Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083 P. R. China Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083 P. R. China;5. Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong SAR, 999077 P. R. China |
| Abstract: | Electrochemical CO2 reduction to value-added chemicals or fuels offers a promising approach to reduce carbon emissions and alleviate energy shortage. Cu-based electrocatalysts have been widely reported as capable of reducing CO2 to produce a variety of multicarbon products (e.g., ethylene and ethanol). In this work, we develop sulfur-doped Cu2O electrocatalysts, which instead can electrochemically reduce CO2 to almost exclusively formate. We show that a dynamic equilibrium of S exists at the Cu2O-electrolyte interface, and S-doped Cu2O undergoes in situ surface reconstruction to generate active S-adsorbed metallic Cu sites during the CO2 reduction reaction (CO2RR). Density functional theory (DFT) calculations together with in situ infrared absorption spectroscopy measurements show that the S-adsorbed metallic Cu surface can not only promote the formation of the *OCHO intermediate but also greatly suppress *H and *COOH adsorption, thus facilitating CO2-to-formate conversion during the electrochemical CO2RR. |
| Keywords: | CO2 Reduction Reaction Cu-Based Electrocatalysts Electrocatalysis Formic Acid S Modification |