Enhancing CO2 electroreduction to CH4 over Cu nanoparticles supported on N-doped carbon

Abstract

The electroreduction of CO₂ to CH₄ has attracted extensive attention. However, it is still a challenge to achieve high current density and faradaic efficiency (FE) for producing CH₄ because the reaction involves eight electrons and four protons. In this work, we designed Cu nanoparticles supported on N-doped carbon (Cu-np/NC). It was found that the catalyst exhibited outstanding performance for the electroreduction of CO₂ to CH₄. The FE toward CH₄ could be as high as 73.4% with a high current density of 320 mA cm⁻². In addition, the mass activity could reach up to 6.4 A mg_Cu⁻¹. Both experimental and theoretical calculations illustrated that the pyrrolic N in NC could accelerate the hydrogenation of *CO to the *CHO intermediate, resulting in high current density and excellent selectivity for CH₄. This work conducted the first exploration of the effect of N-doped species in composites on the electrocatalytic performance of CO₂ reduction.