Electroreduction of CO₂ using copper-deposited on boron-doped diamond (BDD)

Electroreduction of CO₂ was studied at copper-modified boron-doped diamond (Cu-BDD) electrodes as the working electrode. The Cu-BDD electrodes were prepared by electrochemical reduction with various concentrations of CuSO₄ solutions. FE-SEM was utilized to characterize the electrodes. At Cu-BDD electrodes, a reduction peak at around-1.2 V (vs Ag/AgCl) attributtable to CO₂ reductions could be observed by cyclic voltammetry technique of CO₂ bubbled in water containing 0.1M NaCl. Accordingly, electroreduction of CO₂ was conducted at-1.2 V (vs Ag/AgCl) using amperometry technique. The chemical products of the electroreduction analyzed by using HPLC showed the formation of formaldehyde, formic acid, and acetic acid at Cu-BDD electrodes.