Bismuth oxyiodide microflower-derived catalysts for efficient CO₂ electroreduction in a wide negative potential...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The development of highly active and selective electrocatalysts is essential for the carbon dioxide reduction reaction (CO2RR).
• Efficient CO2 conversion into valuable products like formate is a key goal in sustainable chemistry.

Purpose of the Study:

• To design and synthesize novel bismuth-based electrocatalysts for the CO2 reduction reaction.
• To investigate the structure-activity relationship of the bismuth catalysts for enhanced formate selectivity.

Main Methods:

• In situ reduction of bismuth oxyiodide (BiOI) microflowers to form bismuth-based catalysts.
• Characterization of the catalyst composition, including oxidized Bi2O2CO3 and metallic Bi with shortened Bi-Bi bonds.
• Electrochemical evaluation of the catalyst performance for CO2 reduction, measuring faradaic efficiency.

Main Results:

• Successfully synthesized bismuth-based catalysts composed of Bi2O2CO3 and metallic Bi.
• The catalysts exhibited unique local shortened inter-layer Bi-Bi bonds.
• Achieved over 90% formate faradaic efficiency in a wide negative potential region for CO2 reduction.

Conclusions:

• The in situ derived bismuth-based catalysts demonstrate excellent activity and selectivity for CO2 to formate conversion.
• The presence of oxidized Bi2O2CO3, metallic Bi, and specific Bi-Bi bond structures contributes to the high catalytic performance.
• These findings offer a promising pathway for developing efficient electrocatalysts for CO2 utilization.