Sodium-modified V2O5–TiO2 catalysts: 23Na and 51V solid-state NMR study

Abstract

Sodium-doped binary vanadia–titania catalysts were studied using modern high-resolution solid-state NMR techniques, including fast magic angle spinning (MAS) and two-dimensional triple-quantum MAS NMR. The latter technique was engaged in the interpretation of second-order quadrupolar broadened one-dimensional ²³Na MAS NMR spectra. NMR and X-ray powder diffraction data brought together allow identification of sodium- and vanadium-containing species formed in the course of the preparation of the catalysts. The effect of the sodium concentration on the nature of the resulting species is discussed.