Strategies for enhancing electrochemical CO₂ reduction to multi-carbon fuels on copper

Productively harnessing CO₂ as a reactant is of practical interest due to addressing the dual pressures of resource sustainability and environmental sustainability. Electrochemical CO₂ reduction (ECR) offers a promising approach for driving the chemical transformation of CO₂ by exploiting green renewably generated electricity at (near) room temperature and ambient pressure, facilitating a sustainable, low-carbon footprint future. In this work, we provide a comprehensive and timely review of the various avenues that have been developed to date to modulate product selectivity, stability, and efficiency toward C₂₊ using Cu-based electrocatalysts. We discuss how the electrocatalyst structure can be effectively designed in order to boost performance. Special attention is paid to some of the critical intermediate species that shed light on CO₂ reduction paths. We will also discuss the application of in situ and operando spectroscopy, along with computational techniques, that help to improve our fundamental understanding of ECR. Finally, development opportunities and challenge in the conversion of CO₂ into multi-carbon fuels by Cu-based electrocatalysts are presented.