An effective Pd-promoted gold catalyst supported on mesoporous silica particles for the oxidation of benzyl alcohol

A bimetallic Pd-promoted gold catalyst with mesoporous silica nanoparticles (MSNs) as support, PdAu/MSN, was prepared by an impregnation-hydrogen reduction method, and its catalysis for the base-free oxidation of benzyl alcohol was investigated. It was found that adding a small amount of Pd, with a Pd/Au atomic ratio as low as 0.05/1, can significantly decrease the size of the gold particles and thereby remarkably enhance the catalyst's activity for aerobatic oxidation. At the optimal Pd/Au atomic ratio of 0.2/1, the catalyst Pd0.2Au/MSN showed 8 times and 3 times higher activity than the monometallic catalysts Au/MSN and Pd/MSN, respectively. The prepared catalysts were comprehensively characterized by XRD, DRUV-vis, TEM, XPS, and H-2-TPR to correlate the enhanced activity with the promotional effect induced by adding Pd. (C) 2013 Elsevier B.V. All rights reserved.