Design and mechanistic study of advanced cobalt-based nanostructured catalysts for electrochemical carbon dioxide reduction

The advancement of cost-effective nanostructured catalysts for the electrochemical reduction of CO2 to valuable chemicals is of great interest. In the present study, cobalt-oxide nanodendrites were directly grown on a Co substrate and systemically studied towards the electrochemical reduction of CO2. Our electrochemical measurements revealed that the formed Co nanodendrites exhibited superb catalytic activity in comparison to the Co-based catalysts reported in the literature, with a small onset potential (−0.2 V vs RHE) and an extremely high current density for the CO2 reduction. In situ electrochemical attenuated total reflection Fourier transform infrared spectroscopy was employed to elucidate the reduction reaction mechanism, revealing that the formation of formate at the Co nanodendrites proceeded through the formation of a carbon-bound adsorbed *COO- intermediate. The innovative approach and the in-situ FTIR analysis reported in the present study would provide insights in the design and tuning of advanced electrocatalysts for energy and environmental applications.