Effect of perimeter interface length between 2D WO3 monolayer domain and γ-Al2O3 on selective hydrogenolysis of glycerol to 1,3-propanediol Electronic supplementary information (ESI) available. See DOI: 10.1039/c9cy01385g

The relationship between the structure of W species on Pt/WO3/Al2O3 catalysts and their activity for selective hydrogenolysis of glycerol to 1,3-propanediol was investigated. Structural analysis by spectroscopic techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and X-ray adsorption fine structure (XAFS) revealed the formation of two-dimensional WO3 monolayer domains on the surface of gamma -Al2O3 at a WO3 loading level of below 20 wt%. Evaluation of the reduction properties of W species by H-2 temperature programed reduction (TPR) suggested the presence of two kinds of W species with different reduction properties loaded on gamma -Al2O3, and W species at the edge of a WO3 domain was reduced more easily than that inside of a WO3 domain. Furthermore, the length of the perimeter interface between a two-dimensional WO3 monolayer domain and gamma -Al2O3 (W-Al perimeter interface) could be estimated from the difference in their reducibility. The positive correlation between W-Al perimeter interface length and the yield of 1,3-propanediol in hydrogenolysis of glycerol indicated that a W-(OH)-Al site at the W-Al perimeter interface functioned as a main active site.