Electrochemical reduction of CO[sub 2] on a Cu electrode under high pressure: Factors that determine the product selectivity

Journal Article · Mon Aug 01 00:00:00 EDT 1994 · Journal of the Electrochemical Society; (United States)

DOI:https://doi.org/10.1149/1.2055067· OSTI ID:6914595

Hara, Kohjiro; Tsuneto, Akira; Kudo, Akihiko; Sakata, Tadayoshi ^[1]

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1. Tokyo Inst. of Technology, Yokohama (Japan). Dept. of Electronic Chemistry

The selectivity of the electrochemical reduction products of CO[sub 2] on a Cu electrode in aqueous KHCO[sub 3] solution depended remarkably on the CO[sub 2] pressure (<60 atm), stirring condition, and the current density. As the flux of CO[sub 2] to the Cu electrode surface was increased by increasing CO[sub 2] pressure and/or by stirring, the main reduction product was changed in the order of H[sub 2] [yields] hydrocarbons [yields] CO and/or HCOOH. On the other hand, the selectivity of the reduction products was changed in the order of CO and/or HCOOH [yields] hydrocarbons [yields] H[sub 2] by increasing the current density. From these results, it was concluded that the balance between the flux of CO[sub 2] from the bulk solution to the electrode surface and the current density determines which reduction products are produced. Hydrocarbon formation was preferential when the current density was comparable to the maximum CO[sub 2] flux under given condition. The partial current density for maximum hydrocarbon formation occurred at 375 mA cm[sup [minus]2] under CO[sub 2] pressure at 30 atm.

• OSTI ID: 6914595
• Journal Information: Journal of the Electrochemical Society; (United States), Vol. 141:8; ISSN 0013-4651
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
54 ENVIRONMENTAL SCIENCES
10 SYNTHETIC FUELS
CARBON DIOXIDE
REDUCTION
COPPER
CATALYTIC EFFECTS
CARBON MONOXIDE
CONCENTRATION RATIO
CURRENT DENSITY
ELECTROLYSIS
FORMIC ACID
HYDROCARBONS
POTASSIUM CARBONATES
ALKALI METAL COMPOUNDS
CARBON COMPOUNDS
CARBON OXIDES
CARBONATES
CARBOXYLIC ACIDS
CHALCOGENIDES
CHEMICAL REACTIONS
ELEMENTS
LYSIS
METALS
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POTASSIUM COMPOUNDS
TRANSITION ELEMENTS
400400* - Electrochemistry
540120 - Environment
Atmospheric- Chemicals Monitoring &amp; Transport- (1990-)
100200 - Synthetic Fuels- Production- (1990-)