Theoretical study the electrocatalytic performance and mechanism of novel designed electrocatalyst Ru@2DMs for CO2RR

Abstract

Designing and synthesizing high performance CO2RR electrocatalyst is significance for reducing CO2 concentration and mitigating global warming. In this study, density functional theory (DFT) was used to explore the performance of novel designed electrocatalysts, Ru@C3N4(N), Ru@GD(C), Ru@GR(C), Ru@BN(B), 3Ru@C3N4 and 3Ru@GD, for electroreduction of CO2. In view of first protonation step, the probability of CO2RR is higher than HER on 3Ru@C3N4, Ru@GR(C) and Ru@BN(B); while the probability is towards HER rather than CO2RR on Ru@GD(C), Ru@C3N4(N) and 3Ru@GD. It should be noted that the transition metal Ru atom is the only active site for CO2RR; while the active site of the HER are C and N atoms of Ru@GD(C), Ru@C3N4(N) and 3Ru@GD. Hence, although the HER are main reaction on Ru@GD(C), Ru@C3N4(N) and 3Ru@GD, CO2RR would also happen on these surfaces with high probability. Further research indicated that HCOOH and CH4 are the high probability products. For Ru@C3N4(N), Ru@GR(C), and Ru@BN(B), the reduction products is HCOOH with overpotential of 0.36 V, 0.23 V, and 0.75 V respectively; For 3Ru@GD, 3Ru@C3N4 and Ru@GD(C) the reduction products is CH4 with overpotential of 0.48 V, 0.87 V and 0.31 V, respectively. Finally, the AIMD simulations proved the thermal stability of designed electrocatalyst.