Cu-Based Materials for Enhanced C₂₊ Product Selectivity in Photo-/Electro-Catalytic CO₂ Reduction: Challenges and...

Carbon dioxide conversion into valuable products using photocatalysis and electrocatalysis is an effective approach to mitigate global environmental issues and the energy shortages. Among the materials utilized for catalytic reduction of CO₂, Cu-based materials are highly advantageous owing to their widespread availability, cost-effectiveness, and environmental sustainability. Furthermore, Cu-based materials demonstrate interesting abilities in the adsorption and activation of carbon dioxide, allowing the formation of C₂₊ compounds through C-C coupling process. Herein, the basic principles of photocatalytic CO₂ reduction reactions (PCO₂RR) and electrocatalytic CO₂ reduction reaction (ECO₂RR) and the pathways for the generation C₂₊ products are introduced. This review categorizes Cu-based materials into different groups including Cu metal, Cu oxides, Cu alloys, and Cu SACs, Cu heterojunctions based on their catalytic applications. The relationship between the Cu surfaces and their efficiency in both PCO₂RR and ECO₂RR is emphasized. Through a review of recent studies on PCO₂RR and ECO₂RR using Cu-based catalysts, the focus is on understanding the underlying reasons for the enhanced selectivity toward C₂₊ products. Finally, the opportunities and challenges associated with Cu-based materials in the CO₂ catalytic reduction applications are presented, along with research directions that can guide for the design of highly active and selective Cu-based materials for CO₂ reduction processes in the future.