Gold Sols as Catalysts for Glycerol Oxidation: The Role of Stabilizer

Gold nanoparticles (Au NPS), stabilized by polyvinylalcohol (PVA), tetrakishydroxypropylphosphonium chloride (THPC), and citrate, have been synthesized and tested in the liquid-phase oxidation of glycerol. THPC-stabilized Au NPs have been found to exhibit remarkable catalytic activity (TOF=2478 h(-1)) in comparison to PVA- and citrate-stabilized nanoparticles (TOF=715 and 160 h(-1), respectively). The catalytic results can be explained in terms of particle size but aging treatment also revealed the influence of the protective agent. PVA as stabilizer produced small and quite stable gold nanoparticles differently from the THPC system. However PVA also limits the accessibility of reactant to the active site.