(583ep) Electrochemical Reduction of CO2 On Transition Metal Catalysts

The development of a cost effective process for the electrochemical reduction of CO₂ could enable a shift to a sustainable energy economy.  Coupled to a renewable energy source such as wind or solar, such a process could generate carbon neutral fuels or commodity chemicals that are conventionally produced from petroleum.  The key to developing such a process is a catalyst capable of performing the conversion at a low overpotential and high selectivity to the desired product.  Unfortunately, known catalysts do not meet these requirements.  More understanding of the factors that affect catalytic activity are needed to design improved catalysts.

To learn more about the catalytic factors important for CO₂ electroreduction, we have experimentally studied the activity of the transition metals: Au, Ag, Zn, Cu, Pt, Fe, and Ni.  The experimental measurements were made using a custom electrolysis setup allowing for highly sensitive product detection during and after potentiostatic 1 hour electrolysis experiments at potential ranges where currents ranged from ~0.5-10 mA/cm².   

Our experimental data fits well with previous literature reports that suggest that the major products of CO₂ electroreduction are determined by CO binding energy to the metal surface.  Due to the sensitivity of our experimental setup, we have a comprehensive view of what each catalyst does at a range of potentials, contributing a wealth of knowledge to the CO₂ reduction community, including the identification of several minor products that have not been reported before.