1H and 51V high-resolution solid state nuclear magnetic resonance studies of supported V 2O 5/TiO 2 catalysts

Abstract

1H solid state NMR data show the existence of several types of hydroxyl groups on TiO 2 surface, depending on the surface impurities. VOCl 3 selectively interacts with these groups. According to 51V NMR data, the structure of the surface vanadium complexes, independently of the preparation method, is determined by the type of surface hydroxyls. On clean TiO 2 surface at low vanadium concentration two types of surface complexes with vanadium in the distorted tetrahedral environment of oxygen atoms are formed, one of them containing OH groups in the coordination sphere. At high V content associated species, with V in octahedral coordination, are formed. nuclear magnetic resonance studies; solid state; titania; vanadia