Subnanocatalysis for Aerobic Oxidation: Toluene Oxidation with Oxygen using Subnano Metal Particles
Subnanocatalysis by ultra‐small nanoparticles (having sizes of approximately 1 nm) is an emerging research area which is still leading to the discovery of new designs and concepts, especially with regard to catalysis for the aerobic oxidation of hydrocarbons. In the present work, heterogeneous subnanocatalysts (SNCs) containing various noble metals (Cu, Ru, Rh, Pd, or Pt) with finely size‐controlled quantities were synthesized using dendritic poly(phenylazomethine)s as a macromolecular template. These materials exhibit high catalytic performance during toluene oxidation without the use of harmful solvents or explosive oxidants, resulting in the formation of valuable oxidized products, including benzoic acid as the major product. In particular, Pt19 SNC with a narrow particle size distribution exhibits extraordinary catalytic activity, with a turnover frequency of 3238 atom‐1 h‐1, which is 1700 times greater than that obtained by commercial Pt/C catalysts. These unprecedented results suggest the possibility of developing low‐cost, high‐performance industrial catalysis.