Solar conversion of CO2 to CO using Earth-abundant electrocatalysts prepared by atomic layer modification of CuO

The solar-driven electrochemical reduction of CO 2 to fuels and chemicals provides a promising way for closing the anthropogenic carbon cycle. However, the lack of selective and Earth-abundant catalysts able to achieve the desired transformation reactions in an aqueous matrix presents a substantial impediment as of today. Here we introduce atomic layer deposition of SnO 2 on CuO nanowires as a means for changing the wide product distribution of CuO-derived CO 2 reduction electrocatalysts to yield predominantly CO. The activity of this catalyst towards oxygen evolution enables us to use it both as the cathode and anode for complete CO 2 electrolysis. In the resulting device, the electrodes are separated by a bipolar membrane, allowing each half-reaction to run in its optimal electrolyte environment. Using a GaInP/GaInAs/Ge photovoltaic we achieve the solar-driven splitting of CO 2 into CO and oxygen with a bifunctional, sustainable and all Earth-abundant system at an efficiency of 13.4%. Electrochemical reduction of CO 2 to CO is a route to synthesize fuels, but cheaper and more selective catalysts are required. Using a cell equipped with a bipolar membrane and the same Earth-abundant electrocatalyst at each electrode, Schreier et al. selectively produce CO, powered by a triple-junction photovoltaic.