Reaction Environment Engineering for Selective C₃₊ Formation in CO₂ Electroreduction: Progress and Perspectives

Area of Science:

• Electrochemistry
• Catalysis
• Sustainable Chemistry

Background:

• Electrocatalytic CO2 reduction (ECRR) is a promising route for sustainable chemical production.
• While C1 and C2 electrosynthesis are advanced, ECRR to C3+ products suffers from low selectivity.
• Key challenges include low overall C3+ selectivity and poor selectivity for specific C3+ products.

Purpose of the Study:

• To review the main formation mechanisms of C3+ products via ECRR.
• To analyze thermodynamic pathways and identify key reaction branching points.
• To highlight engineering strategies for enhancing C-C coupling and product selectivity.

Main Methods:

• Summarization of three primary formation mechanisms: *CO-*CO-*CO coupling, *CO2-*OCHCH2 coupling (*CO2 insertion), and *CO-*OCHCH2 coupling (*CO insertion).
• Thermodynamic analysis on Cu(100) to construct a comprehensive reaction network.
• Identification of competition between hydrocarbon and oxygenate pathways.

Main Results:

• The study identifies key branching points and the competition between hydrocarbon and oxygenate pathways in ECRR to C3+.
• Reaction environment engineering strategies, including catalyst architecture and electrolyte interface engineering, are highlighted.
• These strategies show promise for simultaneously promoting C-C couplings and tuning post-coupling selectivity.

Conclusions:

• ECRR to C3+ products requires addressing low selectivity issues.
• Understanding reaction mechanisms and employing advanced engineering strategies are crucial.
• Further research is needed to overcome current challenges and advance ECRR to C3+ conversion.