Selective bimetallic sites supported on graphene as a promising catalyst for CO₂ Reduction: A first-principles study

Developing efficient and inexpensive electrocatalysts for CO₂ reduction reaction (CRR) has been a key scientific issue. Several factors limit the electrocatalyst efficiency of materials, including the relatively high overpotential, low stability and low selectivity for CRR. The use of bimetallic catalyst systems is an efficient approach to improve the catalytic performance. In this study, by using the density functional theory (DFT) calculations, we explore the CRR processes of three different bimetal doped graphenes (M¹M²/DG (M¹, M² = Cu, Fe, Ni)). Various reduction reaction pathways of CO₂ lead to different products, including CH₄, CH₃OH, HCOOH and CO. The E_ads of different intermediates on different M¹M²/DG, the free energy variation and the overpotential of the different M¹M²/DG were analyzed. The obtained results confirm the CO₂ capture ability of all the studied M¹M²/DG systems. The low overpotential of 0.49 V for Cu_Ni/DG is even lower than that of the most outstanding metallic electrocatalyst (Cu (2 1 1)). This work provides useful information for the development of efficient CRR electrocatalysts.