Anode Reaction Control for a Single-Compartment Electrochemical CO₂ Reduction Reactor with a Surface-Activated...

The electrochemical reaction of carbon dioxide (CO₂ ) in aqueous electrolyte solutions is attracting increasing attention for sustainable chemical production. Boron-doped diamond (BDD) electrodes have been previously shown to be very effective for the stable electrochemical production of formic acid from CO₂ . Typically, the electrochemical production of formic acid by CO₂ reduction (CO₂ R) reaction is performed with a dual-compartment flow reactor equipped with a membrane separator. The problems caused by the membrane separator, such as scaling-up, complicated operational control and materials costs can be solved using a membrane free single-compartment reactor. Here we demonstrate anode reaction control for a single-compartment CO₂ R flow reactor using a surface-activated BDD cathode and achieve a Faradaic efficiency for formic acid production of over 70 %.