Organometallic Frameworks for Efficient Electrocatalytic CO₂ Reduction Reactions.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrocatalytic conversion of carbon dioxide (CO2) using renewable electricity is a key strategy for CO2 reduction and energy storage.
• Metal-organic frameworks (MOFs) are promising CO2 reduction reaction (CO2RR) catalysts due to their structure and surface area, but suffer from low conductivity.
• Enhancing electron transfer and CO2 activation in MOFs is crucial for improving CO2RR performance.

Purpose of the Study:

• To synthesize novel organometallic frameworks with enhanced CO2RR performance.
• To investigate the role of Metal-C bonds and specific coordination motifs in improving catalytic activity.
• To achieve high current densities and selectivity in CO2 electroreduction.

Main Methods:

• Synthesis of two organometallic frameworks featuring direct carbon-silver (Metal-C) connectivity.
• Characterization of the electronic structure and coordination motifs (σ-π) within the frameworks.
• Electrocatalytic testing for CO2 reduction reaction (CO2RR) performance evaluation, including current densities and Faraday efficiencies.

Main Results:

• The synthesized frameworks exhibit enhanced electron transfer capability and CO2 activation due to the σ-π coordination motif.
• Exceptional CO Faraday efficiencies (FE_CO) exceeding 90% were achieved at industrially relevant current densities (> 500 mA cm⁻²).
• Performance surpasses most previously reported MOF-based CO2RR catalysts.

Conclusions:

• Organometallic frameworks with Metal-C bonds offer a novel design strategy for efficient CO2 electroreduction.
• The developed materials demonstrate significant potential for practical industrial CO2 electroreduction processes.
• This work paves the way for advanced catalysts in carbon capture and utilization technologies.