Excitonic Au4Ru2(PPh3)2(SC2H4Ph)8 cluster for light-driven dinitrogen fixation

摘要

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.