Amino acid modified copper electrodes for the enhanced selective electroreduction of carbon dioxide towards hydrocarbons

Abstract

Electroreduction of carbon dioxide to hydrocarbons has been proposed as a promising way to utilize CO₂ and maintain carbon balance in the environment. Copper (Cu) is an effective electrocatalyst for such a purpose. However, the overall selectivity towards hydrocarbons on Cu-based electrodes is still very limited. In this work, we develop a general amino acid modification approach on Cu electrodes for the selective electroreduction of CO₂ towards hydrocarbons. A remarkable enhancement in hydrocarbon generation is achieved on these modified copper electrodes, regardless of the morphology of the Cu electrodes. A density functional theory calculation reveals that the key intermediate CHO* is stabilized by interacting with –NH₃⁺ of the adsorbed zwitterionic glycine. Our results suggest that amino acids and their derivatives are promising modifiers in improving the selectivity of hydrocarbons in CO₂ electroreduction.