Selective Sieving Effect of Multi-Atomic Bismuth Interfaces for Efficient Formate Electrosynthesis and Evolution at...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrocatalytic CO2 conversion is crucial for sustainable chemical production.
• Developing stable and efficient multi-atomic interface architectures for CO2 reduction remains a significant challenge, especially under industrial conditions.

Purpose of the Study:

• To engineer multi-atomic bismuth interfaces for enhanced electrocatalytic CO2 conversion.
• To investigate the performance and stability of these interfaces across a wide pH range.
• To develop integrated electrolyzer systems for high-value chemical synthesis.

Main Methods:

• Precise engineering of multi-atomic Bi interfaces (Bi0/Biδ+-O moiety) by embedding Bi single atoms and clusters into porous Bi2O3-x nanosheets.
• Electrocatalytic CO2 conversion performance evaluation in various electrolytes (alkaline, neutral).
• Fabrication and testing of symmetrical/asymmetrical electrolyzers coupled with methanol electrooxidation catalysts.
• In situ characterizations and theoretical calculations to elucidate reaction mechanisms.

Main Results:

• Achieved outstanding CO2 conversion to formate with high Faradaic efficiency (FEformate > 90%) at low potentials (-0.5 V vs RHE).
• Demonstrated exceptional long-term stability (>150 h) across a wide pH range.
• Developed electrolyzers producing formate at both electrodes with a high production rate (4980 µmol h-1 cm-2) under industrial current density.
• Unraveled the mechanism involving interfacial atomic sieving effects enhancing *OCHO formation and suppressing H2 evolution.

Conclusions:

• The engineered multi-atomic Bi interfaces provide a highly efficient and stable platform for electrocatalytic CO2 conversion.
• This approach facilitates the sustainable synthesis of high-added value chemicals, including formate for potential urea production.
• The study establishes a pathway for advanced electrochemical synthesis and sustainable chemical evolution.