Efficient CO₂ electroreduction to ethanol enabled by tip-curvature-induced local electric fields.

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrocatalytic reduction of carbon dioxide (CO2) is crucial for CO2 utilization.
• Achieving high selectivity for multicarbon products like ethanol remains a significant challenge.

Purpose of the Study:

• To develop a novel catalyst for efficient and selective electroreduction of CO2 to ethanol.
• To investigate the role of catalyst nanostructure and local electric fields in CO2 electroreduction.

Main Methods:

• Synthesis of CuO nanoflower catalysts with engineered tip curvature.
• Electrochemical measurements to determine product selectivity and formation rates.
• In situ Raman spectroscopy to study reaction intermediates and surface species.

Main Results:

• The CuO nanoflower catalyst achieved 47% ethanol faradaic efficiency (FEethanol) and a formation rate of 320 μmol h-1 cm-2.
• Overall C2+ product faradaic efficiency (FEC) reached approximately 77.8%.
• Sharp catalyst tips generated strong local electric fields, enhancing CO2 activation and C-C coupling.

Conclusions:

• Engineered CuO nanoflower tips effectively promote CO2 electroreduction to ethanol.
• Local electric fields and enhanced *OH coverage are key factors for high ethanol selectivity.
• This work offers a new strategy for designing catalysts for CO2 conversion to valuable chemicals.