Jump to main content
Jump to site search

Issue 8, 1989
Previous Article Next Article

Formation of hydrocarbons in the electrochemical reduction of carbon dioxide at a copper electrode in aqueous solution

Abstract

Electroreduction of CO2 at Cu in aqueous inorganic electrolytes was studied by means of voltammetric, coulometric and chronopotentiometric measurements. CO, CH4, C2H4, EtOH and PrnOH are produced at ambient temperatures. Formation of CO predominates at less negative potentials (more positive than –1.2 V vs. NHE); hydrocarbons and alcohols are favourably produced below –1.3 V vs. NHE, where the Faradaic efficiency of CO drops. CO, formed as an intermediate from CO2, is adsorbed on the Cu electrode, interfering with cathodic hydrogen formation. The adsorption strength of CO on Cu is very weak as compared with that on Pt. Adsorbed CO is reduced to Hydrocarbons and alcohols at more negative potentials. The product distribution from CO2 depends strongly upon the electrolytes employed. Formation of C2H4 and alcohols is favoured in KCl, K2SO4, KClO4 and dilute HCO3 solutions, whereas CH4 is preferentially produced in relatively concentrated HCO3 and phosphate solutions. The product selectivity depends upon availability of hydrogen or protons on the surface, which is controlled by pH at the electrode. The pH at the electrode is greatly affected by the electrolyte, since OH is released in the electrode reactions. The production of hydrocarbons and alcohols is discussed in comparison with the mechanism of the Fishcher–Tropsch reaction.

Back to tab navigation

Article type: Paper
DOI: 10.1039/F19898502309
J. Chem. Soc., Faraday Trans. 1, 1989,85, 2309-2326

  •   Request permissions

    Formation of hydrocarbons in the electrochemical reduction of carbon dioxide at a copper electrode in aqueous solution

    Y. Hori, A. Murata and R. Takahashi, J. Chem. Soc., Faraday Trans. 1, 1989, 85, 2309
    DOI: 10.1039/F19898502309

Search articles by author

Spotlight

Advertisements