Nitrogen and Boron Co‐Doped Carbon Spheres for Carbon Dioxide Electroreduction

Abstract The electrochemical CO 2 reduction reaction (CO 2 RR) powered by renewable electricity is a promising route to close the carbon cycle, but it suffers from low product selectivity and high overpotential. Here we develop nitrogen and boron co‐doped hollow carbon spheres (NB−CS) through the pyrolysis of a mixture comprising low‐molecular‐weight phenolic resols, melamine and boric acid. The optimized NB−CS catalyst presents high CO 2 RR performance and achieves a CO Faradaic efficiency of 95.1% at a low overpotential of 310 mV, superior to carbon spheres doped with nitrogen or boron alone. Structural and electrochemical characterizations indicate that the efficient CO 2 RR to CO over the NB−CS catalyst is likely ascribed to the unique graphitized architecture along with high conductivity, large surface area and high density of exposed N and B reactive sites. This work highlights opportunities to use cost‐effective and readily available carbon nanomaterials as efficient CO 2 RR catalysts.