Excitonic Au(4)Ru(2)(PPh(3))(2)(SC(2)H(4)Ph)(8) cluster for light-driven dinitrogen fixation

The surface plasmon resonance of metal nanoparticles has been widely used to improve photochemical transformations by plasmon-induced charge transfer. However, it remains elusive for the molecular-like metal clusters with non-metallic or excitonic behavior to enable light harvesting including electron/hole pair production and separation. Here we report a paradigm for solar energy conversion on an atomically precise Au(4)Ru(2) cluster supported on TiO(2) with oxygen vacancies, in which the electron–hole pairs can be directly generated from the excited Au(4)Ru(2) cluster and the TiO(2) support, and the photogenerated electrons can transfer to the Ru atoms. Importantly, the Ru atoms in the Au(4)Ru(2) cluster are capable of injecting the electrons into adsorbed N(2) to activate N(2) molecules. The cooperative effect in the supported Au(4)Ru(2) catalyst efficiently boosts the photocatalytic activity for N(2) fixation in comparison with homogold (Au(n)) clusters.