Deposition of Gold Clusters on Porous Coordination Polymers by Solid Grinding and Their Catalytic Activity in Aerobic Oxidation of Alcohols

The direct deposition of Au clusters onto various kinds of porous coordination polymers (PCP) including MOF-5 by solid grinding with a volatile organogold complex without using organic solvents was reported. The results show that the PCP supports, Al-MIL53 is able to support Au clusters with the smallest size of below 1 nm, resulting in a mean diameter of 1.5 nm with a standard deviation of 0.7 nm. The size of Au is found to be strongly dependent on the metallic properties, porous structures, and pore size of PCPs. The Au/PCP exhibit high catalytic activity for the aerobic oxidation of alcohols in the liquid phase, while Au/MOF-5 shows the highest catalytic activity to obtain methyl benzoate. Au clusters on Cu-PCPs are found to exhibit high selectivity towards benzaldehyde and the catalytic activity order of Au/PCPs in the oxidation of 1-phenylethanol is similar to the oxidation of benzyl alcohol.