Characterization of AlNbO4 and vanadium oxide catalysts supported on AlNbO4 by 27Al and 51V solid state NMR spectroscopy

Abstract

²⁷ Al Solid state NMR spectroscopy of Al₂O₃–Nb₂O₅ mixtures (Al/Nb = 1) reveals three types of aluminium centres corresponding to tetrahedral, pentagonal and octahedral coordination;⁵¹ V solid state NMR spectra of vanadium oxide, dispersed on Al–Nb oxides at a coverage lower than a monolayer reveal two types of vanadia species, one due to a symmetric tetrahedral environment and the other due to a distorted or octahedral coordination (different from V₂O₅).