Synergistic effect on Au-Pd bimetallic catalyst during oxidation of benzyl alcohol to sodium benzoate

A series of AuPd/CeO2 bimetallic catalysts with different Au/Pd molar ratios were investigated and their catalytic performance in the oxidation of benzyl alcohol to sodium benzoate and benzoic acid under solvent-free conditions was studied. The supported catalysts were characterized by X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The Au-Pd nanoparticles were successfully deposited onto CeO2 as a homogeneous alloy. The activity of the bimetallic catalysts was superior to that of the corresponding monometallic catalysts. This improvement was attributed to the synergistic effect between Au and Pd. The catalyst with an Au/Pd molar ratio of 3/1 showed the best catalytic performance (the yield of benzoic acid reached 92%), and it could be easily recovered and reused for more than seven successive reactions without significant loss of activity.

Graphical AbstractA series of AuPd/CeO2 bimetallic catalysts with different Au/Pd molar ratios were successfully prepared and applied in the catalytic oxidation of benzyl alcohol to benzoic acid and sodium benzoate with high yields. The 3Au1Pd/CeO2 catalyst shows optimal performance and was easily recovered and reused for more than seven successive reactions without significant loss of activity, which was attributed to the synergistic effect between Au and Pd.Figure optionsDownload full-size imageDownload as PowerPoint slide