Print Email Facebook Twitter A Quantitative Analysis of Electrochemical CO2 Reduction on Copper in Organic Amide and Nitrile-Based Electrolytes Title A Quantitative Analysis of Electrochemical CO2 Reduction on Copper in Organic Amide and Nitrile-Based Electrolytes Author Sajeev Kumar, A. (TU Delft Large Scale Energy Storage) Moura de Salles Pupo, M. (TU Delft Large Scale Energy Storage) Petrov, K.V. (TU Delft ChemE/Transport Phenomena) Ramdin, M. (TU Delft Engineering Thermodynamics) van Ommen, J.R. (TU Delft ChemE/Product and Process Engineering) de Jong, W. (TU Delft Large Scale Energy Storage) Kortlever, R. (TU Delft Large Scale Energy Storage) Date 2023-07-03 Abstract Aqueous electrolytes used in CO2 electroreduction typically have a CO2 solubility of around 34 mM under ambient conditions, contributing to mass transfer limitations in the system. Non-aqueous electrolytes exhibit higher CO2 solubility (by 5–8-fold) and also provide possibilities to suppress the undesired hydrogen evolution reaction (HER). On the other hand, a proton donor is needed to produce many of the products commonly obtained with aqueous electrolytes. This work investigates the electrochemical CO2 reduction performance of copper in non-aqueous electrolytes based on dimethylformamide (DMF), n-methyl-2-pyrrolidone (NMP), and acetonitrile (ACN). The main objective is to analyze whether non-aqueous electrolytes are a viable alternative to aqueous electrolytes for hydrocarbon production. Additionally, the effects of aqueous/non-aqueous anolytes, membrane, and the selection of a potential window on the electrochemical CO2 reduction performance are addressed in this study. Experiments with pure DMF and NMP mainly produced oxalate with a faradaic efficiency (FE) reaching >80%; however, pure ACN mainly produced hydrogen and formate due to the presence of more residual water in the system. Addition of 5% (v/v) water to the non-aqueous electrolytes resulted in increased HER and formate production with negligible hydrocarbon production. Hence, we conclude that aqueous electrolytes remain a better choice for the production of hydrocarbons and alcohols on a copper electrode, while organic electrolytes based on DMF and NMP can be used to obtain a high selectivity toward oxalate and formate. Subject CO2 electroreductionnon-aqueous electrolytescopper electrodeelectrolyte effectswater effects To reference this document use: http://resolver.tudelft.nl/uuid:b70b096f-8404-4d8f-8c92-5fa93be0ec9e DOI https://doi.org/10.1021/acs.jpcc.3c01955 ISSN 1932-7455 Source The Journal of Physical Chemistry C, 127 (27), 12857-12866 Part of collection Institutional Repository Document type journal article Rights © 2023 A. Sajeev Kumar, M. Moura de Salles Pupo, K.V. Petrov, M. Ramdin, J.R. van Ommen, W. de Jong, R. Kortlever Files PDF acs.jpcc.3c01955.pdf 3.01 MB Close viewer /islandora/object/uuid:b70b096f-8404-4d8f-8c92-5fa93be0ec9e/datastream/OBJ/view