Syngas production from electrochemical reduction of CO2 at high current density using oxide derived Zn/Cu nanocomposite

Reduction of CO2 in an electrochemical reactor may become a future technology for the production of syngas. This technology uses CO2 and water co-electrolysis and has the potential to produce variable CO/H-2 ratio, which can become feedstock for various processes. However, developing an electrocatalyst selective for ERC is a great challenge. Further, high current density and low overpotential are essential for the electroreduction of the ERC. In this paper, oxide derived Zn/Cu electrocatalysts with different concentrations of Cu is reported using facile wet chemical synthesis route for the tunable syngas production. Physico-chemical analysis of the electrocatalysts revealed that by varying the concentration of Cu into the oxide derived Zn/Cu composite, fraction of Cu distributed into the ZnO crystal and composite form can be tunned. This inturn generates a synergic effect and reduces the charge transfer resistance towards ERC. By controlling the Cu concentration in the oxide derived Zn/Cu electrocatalyst CO/H-2 ratio can be tunned over a wide range (0.84, 0.76, 0.25) at different current densities (20.4, 8.8, 37 mA/cm(2)). Oxide derived Zn/Cu electrocatalyst shows potential for electrochemical reduction of CO2 to syngas with tunnable CO/H-2 ratio by utilizing renewable energy.