Fabrication of a highly dispersed/active Pd nanoparticle supported catalyst: a cation-assisted reduction method in ethylene glycol–water solution at mild temperature

Development of sustainable routes to synthesize precious metal supported catalysts is of great importance because of their wide applications in the catalysis field. This paper reported a controllable and recyclable cation-assisted reduction route to fabricate a palladium nanoparticle supported catalyst. At 323 K, highly dispersed Pd/Al2O3-CARM was prepared through introducing M2+ (M = Mn, Zn or Cu) ions to promote the reduction of H2PdCl4 in ethylene glycol-water solution, and the residual filtrate after preparation could be recycled to prepare Pd/Al2O3 catalysts. A turnover frequency of 300 × 102 h-1 was obtained for Pd/Al2O3-CARMn in solvent-free aerobic oxidation of benzyl alcohol to benzaldehyde.