Modeling and simulating electrochemical reduction of CO2 in a microfluidic cell

A steady-state, isothermal model has been presented for the electrochemical reduction of CO₂ to CO in a microfluidic cell. The model integrates the transports of charge, mass, and momentum with electrochemistry. After validation using experimental polarization curves, extensive simulations reveal a trade-off between the two performance measures: current density and CO₂ conversion. A more negative overpotential at the cathode increases the partial current density for CO₂ reduction, but decreases the Faradaic efficiency. As feed CO₂ concentration or flow rate increase, the current density and faradaic efficiency increase, but CO₂ conversion decreases slightly. A longer channel improves CO₂ conversion, but at the cost of Faradaic efficiency and current density.