Abstract
Cu metal is the only pure transition metal catalyst that yields significant quantities of hydrocarbons and alcohols as a product of the electrochemical CO2 reduction reaction. However, Cu also yields H2 as a product of the competing hydrogen evolution reaction. A catalyst with enhanced selectivity for hydrocarbons and alcohols over H2 is much sought after to aid in transitioning from a reliance on fossil fuels to alternative fuels. A recent study found Cu nanoparticles with irregular structures exhibited enhanced activity for producing methane and methanol from CO2 compared to both bulk Cu surfaces and regular Cu nanoparticles. In the present work, the catalytic activity of these systems for the competing hydrogen evolution reaction was assessed to probe the selectivity of the irregular Cu nanoparticles for the two reactions. Our findings indicate that barriers to H adsorption and H2 desorption for the irregular nanoparticles remain high and that selectivity for CO2 reduction is likely maintained for these catalysts.