Facet effect of Pt nanocrystals on catalytical properties toward glycerol oxidation reaction

Using nanocrystals with specific crystal facets is an effective way to enhance activity and selectivity for numerous catalytic reactions . However, the intrinsic facet effect is not fully understood. Herein, using Pt catalyzed glycerol oxidation reaction as the model system, the intrinsic facet effect on catalytic property is evaluated by three kinds of Pt nanocrystal catalysts with cubic, spherical and tetrahedral shapes. Size effect, support effect, surfactant effect as well as the metal-support interaction of the catalysts are avoided to the maximum extent. The supported Pt nanocubes enclosed by Pt(1 0 0) facets are found to exhibit much higher catalytic activity and stability for the aerobic oxidation of glycerol than catalysts with Pt nanotetrahedrons enclosed by Pt(1 1 1) facets. DFT calculations indicate that the adsorption of oxygen and glycerol would materialize easier on Pt(1 0 0) than on Pt(1 1 1). Furthermore, Pt(1 0 0) may prevent deactivation caused by product adsorption as well.