Rational Manipulation of Intermediates on Copper for CO₂ Electroreduction Toward Multicarbon Products

Abstract

Excess greenhouse gas emissions, primarily carbon dioxide (CO₂), have caused major environmental concerns worldwide. The electroreduction of CO₂ into valuable chemicals using renewable energy is an ecofriendly approach to achieve carbon neutrality. In this regard, copper (Cu) has attracted considerable attention as the only known metallic catalyst available for converting CO₂ to high-value multicarbon (C₂₊) products. The production of C₂₊ involves complicated C–C coupling steps and thus imposes high demands on intermediate regulation. In this review, we discuss multiple strategies for modulating intermediates to facilitate C₂₊ formation on Cu-based catalysts. Furthermore, several sophisticated in situ characterization techniques are outlined for elucidating the mechanism of C–C coupling. Lastly, the challenges and future directions of CO₂ electroreduction to C₂₊ are envisioned.

Keywords

CO₂ electroreduction / Copper-based electrocatalysts / Multicarbon products / Intermediate / C–C coupling

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