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.