Ultraefficient homogeneous catalyst for the CO2-to-CO electrochemical conversion

Area of Science:

• Electrochemistry
• Catalysis
• Materials Science

Background:

• Developing efficient catalysts for carbon dioxide (CO2) reduction is crucial for sustainable chemistry.
• Iron porphyrins are promising candidates for CO2 conversion due to their tunable electronic properties.

Purpose of the Study:

• To synthesize and characterize a novel electrogenerated iron(0) porphyrin catalyst for CO2-to-CO conversion.
• To evaluate the catalytic performance, including selectivity, overpotential, and turnover frequency.
• To establish a general strategy for optimizing porphyrin-based CO2 reduction catalysts.

Main Methods:

• Synthesis of a tetraphenylporphyrin derivative with specific ortho-, ortho'-phenol and perfluorinated substituents.
• Electrochemical generation of the Fe(0) catalyst.
• Electrocatalytic testing for CO2 reduction to CO.
• Benchmarking using catalytic Tafel plots.

Main Results:

• A highly efficient electrogenerated Fe(0) porphyrin catalyst was successfully obtained.
• The catalyst exhibited excellent selectivity for CO2-to-CO conversion with a nearly quantitative CO faradaic yield.
• It demonstrated a low overpotential and high turnover frequency, surpassing other known homogeneous molecular catalysts.
• Comparison with a related catalyst highlighted a strategy for substituent optimization.

Conclusions:

• The novel Fe(0) porphyrin catalyst represents a significant advancement in homogeneous molecular catalysis for CO2 reduction.
• The findings provide a foundation for designing next-generation catalysts with tailored substituent patterns for enhanced performance.
• This work contributes to the development of efficient technologies for carbon utilization and mitigation.