Composition Engineering Opens an Avenue Toward Efficient and Sustainable Nitrogen Fixation

In this work, we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active sites as exemplified by diatomic metals anchored graphdiyne via the combination of hierarchical high-throughput screening, first-principles calculations, and molecular dynamics simulations. Totally 43 highly efficient catalysts feature ultralow onset potentials (|U_onset| ≤ 0.40 V) with Rh-Hf and Rh-Ta showing negligible onset potentials of 0 and −0.04 V, respectively. Extremely high catalytic activities of Rh-Hf and Rh-Ta can be ascribed to the synergistic effects. When forming heteronuclears, the combinations of relatively weak (such as Rh) and relatively strong (such as Hf or Ta) components usually lead to the optimal strengths of adsorption Gibbs free energies of reaction intermediates. The origin can be ascribed to the mediate d-band centers of Rh-Hf and Rh-Ta, which lead to the optimal adsorption strengths of intermediates, thereby bringing the high catalytic activities. Our work provides a new and general strategy toward the architecture of highly efficient catalysts not only for electrocatalytic nitrogen reduction reaction (eNRR) but also for other important reactions. We expect that our work will boost both experimental and theoretical efforts in this direction.