Theoretical study of a CuCo dual-atom catalyst for nitrogen fixation.

Developing low-cost catalysts for highly efficient nitrogen reduction reaction (NRR) in industrial applications is a great challenge. Dual-atom catalysts (DACs) have also aroused scientific interest as potential NRR catalysts due to their possible higher activity and atom utilization than single atom catalysts. Using density functional theory, we have investigated the NRR performances of heteronuclear CuCo DACs with different coordination configurations. Comparisons with the possible Cu or Co SACs and homonuclear dual-atom catalysts for the NRR performance were also made. We find that O-CuCo-N DAC has superior NRR performance, where the NRR easily takes place through the alternating pathway from the side-on N adsorption mode and the potential limiting step is the first hydrogenation step (NN → NHN) with a Gibbs free energy change of 0.55 eV. The good activity of O-CuCo-N DAC benefits from the regulation provided by Cu and the coordination environment. In addition, O-CuCo-N DAC also exhibits good selectivity and durability.