Sorbate-induced changes in the framework of the titanosilicate ETS-10 as detected by 29Si MAS NMRspectroscopy and X-ray powder diffraction

Abstract

The framework of ETS-10 undergoes reversible structural changes upon dehydration and rehydration. Pronounced differences in the ²⁹Si MAS NMR spectra clearly indicate rearrangements in the local environment, while the X-ray powder diffraction patterns provide evidence for a long-range effect of the guest/host interaction. A detailed analysis of the structural changes by XRD is hampered by the known disorder of the framework of ETS-10. The adsorption of other polar molecules such as methanol and ammonia also leads to fingerprint-like ²⁹Si MAS NMR spectra. Less pronounced variations in the ²⁹Si MAS NMR line shape are observed upon adsorption of non-polar species such as n-pentane.