Highly effective Ru-based Heusler alloy catalysts for N2 activation: A theoretical study

In the present study, we investigate the catalytic ability of Heusler alloys towards N2 decomposition which is the main obstacle to nitrogen reduction reaction (NRR). First-principles methods were used to calculate the adsorption energies and dissociation barriers of nitrogen molecules on the (110) and (001) surfaces of Ru-based Heusler alloys (Ru2YZ, Y = Sc, Ti, V, Fe; Z = Sn, Ga, Ge, As, P). The electron-rich Ru atoms on the Ru-based Heusler alloy surfaces can significantly improve the adsorption activity and reduce the decomposed energy barrier of N2 molecules. A linear relationship between charges of all components, d-band-center, and N2 adsorption energy is predicted to reveal the factors that affect adsorption. The (001) surfaces of Ru2ScZ and Ru2TiZ are highly effective for N2 activation with lower N2 energy barriers around 0.4 eV. The unique catalytic performance of Ru-based Heusler alloys can be attributed to the synergistic role of the electronic effect and geometric effect of the active sites on the ordered alloy surfaces. Our theoretical results provide a strategy for the rational design of high-performance NRR electrocatalysts.