Synergistic electrode design for efficient CO₂ electrolysis to multicarbon products at elevated temperatures.

Area of Science:

• Electrochemistry
• Catalysis
• Chemical Engineering

Background:

• Electrocatalytic CO2 reduction (CO2RR) is crucial for industry.
• Understanding temperature effects (>333 K) on CO2RR in flow cells is limited.
• Elevated temperatures present challenges and opportunities for multi-carbon (C2+) production.

Purpose of the Study:

• Investigate temperature-dependent CO2RR behavior in flow cells.
• Address challenges of high-temperature CO2RR for C2+ production.
• Develop strategies to enhance C2+ selectivity and reactor stability at elevated temperatures.

Main Methods:

• Designed hydrophobic-enhanced Pd-Cu2O/polytetrafluoroethylene (PTFE)/Ag tandem electrodes.
• Operated CO2RR flow cells at elevated temperatures (348 K).
• Evaluated catalyst stability, electrode flooding, and product selectivity.

Main Results:

• Optimized electrodes achieved >70% Faradaic efficiency for C2+ products.
• High performance was maintained across industrially relevant current densities (200-1000 mA cm−2).
• C2+ cathodic energy efficiency increased 1.3 times compared to ambient conditions.

Conclusions:

• Rational electrode design overcomes challenges of high-temperature CO2RR.
• Elevated temperatures can be leveraged as a kinetic and thermodynamic advantage for C2+ production.
• The developed strategy offers a promising paradigm for industrial CO2 electrolysis.