Implicating the Role of Au−H Bonds in Photochemical N ₂ Fixation by Ruthenium‐Doped Gold Clusters

Dinitrogen fixation through the Nitrogen Reduction Reaction (NRR) under mild conditions without the use of sacrificial agents has its share of formidable hurdles. It has been shown recently that Ru-doped Au nanoclusters can reduce N₂ molecules to NH₃ only in the presence of UV-Vis light in aqueous medium. Herein, using theoretical techniques (Density Functional Theory), we shed light on the mechanistic avenues traversed to achieve this prodigious chemical feat. Our findings suggest that the bimetallic Au₂₂Ru₆ cluster successfully accomplishes the NRR process under ambient pressure and temperature conditions by the virtue of its bifunctional nature. Contrary to the existing views, we find that NRR propagates through an alternative associative pathway, where the Ru dopant assists in N₂ adsorption while the Au-H bonds formed from Au-assisted water splitting are implicated in facilitating NRR.