Unlocking the Activity of Molecular Assemblies for CO₂ Electroreduction in Zero-Gap Electrolysers via Catalyst Ink...

Area of Science:

• Electrochemistry
• Catalysis
• Materials Science

Background:

• Electrochemical reduction of carbon dioxide (CO2) to carbon monoxide (CO) is crucial for sustainable chemical production.
• Silver-based catalysts, particularly Ag-BIAN complexes, offer tunable properties and high activity for CO2 electrolysis.
• Zero-gap electrolyzers (ZGEs) are advanced systems for efficient CO2 conversion.

Purpose of the Study:

• To investigate the effect of ink composition on the performance of Ag-BIAN based gas diffusion electrodes (GDEs) in ZGEs.
• To identify optimal solvent-catalyst and solvent-carbon additive combinations for GDE fabrication.
• To reduce the cost and time associated with optimizing GDEs for CO2 electrolysis.

Main Methods:

• Systematic exploration of ink compositions for Ag-BIAN GDEs.
• Sedimentation analyses to determine optimal solvent-catalyst and solvent-carbon additive interactions.
• Performance evaluation of GDEs in ZGEs at 60 °C and 600 mA cm⁻².

Main Results:

• Solvent choice and ink dilution critically influence CO2 reduction efficiency.
• Achieved up to 67% Faradaic efficiency for CO production (FECO) at 600 mA cm⁻².
• Demonstrated high performance with low catalyst loadings (0.2 mg cm⁻²).

Conclusions:

• Ink engineering is vital for optimizing Ag-BIAN GDEs in ZGEs.
• Findings facilitate the transition from laboratory-scale H-type cells to industrial ZGE systems.
• Tailored ink formulations enhance CO2 electrolysis efficiency and catalyst utilization.