Improved performance of electrochemical reduction of CO2 to HCOOH by Cu incorporation into the supported Au monolayer on tungsten carbide: A DFT study

Electrochemical reduction of CO2 into useful chemicals and fuels is a promising strategy to achieve carbon neutrality and storage of renewable electricity. But the realization of industrial application of this technology is hindered by the high energy consumption and low product selectivity. Using the first-principles methods, we explored the mechanism of electrochemical reduction of CO2 on Cu1Au8/WC(0001), in comparison with that on AuML/WC(0001) and CuML/WC(0001). The calculated results showed that incorporating of Cu into Au monolayer significantly enhanced the electrochemical adsorption of CO2, promoting the generation of HCOOH on the alloy surface. Electronic properties such as charge density differences (CDD), Bader charges and density of states (DOS) were investigated to reveal the intrinsic physical origin of the enhanced interaction between OCHO and the catalyst, which results in the improvement in the selectivity and reactivity of CO2 reduction to formic acid (HCOOH) on Cu1Au8/WC(0001). Cu1Au8/WC(0001) was confirmed to be a promising bifunctional catalyst for the efficient conversion of toxic CO to CO2 and selectively reduction of CO2 to useful value-added chemical HCOOH. This work provides a clue to design supported alloy catalysts with high product selectivity and catalytic activity for CO2RR.