Enhanced Activity for CO2 Electroreduction on a Highly Active and Stable Ternary Au-CDots-C3N4 Electrocatalyst

Electrochemical reduction of CO2 to carbon-containing fuels possesses the potential to solve the environmental issues caused by excess CO2 in the atmosphere. Herein, we introduce a ternary Au-CDots-C3N4 electrocatalyst for efficiently reducing CO2 to CO. The ternary catalyst exhibited significantly enhanced activity and stability for CO2 electroreduction in comparison with pure Au NPs. The Au-CDots-C3N4 electrocatalyst demonstrates a high CO FE of ∼79.8% at −0.5 V and a 2.8-fold enhancement of current density (with the Au loading only 4 wt %) at −1.0 V relative to pure Au NPs. The DFT calculations and experimental observations indicate that the high activity toward CO2RR originates from the synergetic effect among Au NPs, CDots, and C3N4 and the capability of H+ and CO2 adsorption from CDots. The long-term stability tests demonstrate that the electrocatalyst can be used for over 8 h without obvious deactivations and maintained its activity over 60 days under normal conditions.