The interaction of water molecules with the surface of hybrid silica-based mesoporous materials is studied by 29Si, 1H and 13C solid-state NMR and IR spectroscopy, with the support of ab initio calculations. The surface of aminopropyl-grafted mesoporous silica nanoparticles is studied in the dehydrated state and upon interaction with controlled doses of water vapour. Former investigations described the interactions between aminopropyl and residual SiOH groups; the present study shows the presence of hydrogen-bonded species (SiOH to NH2) and weakly interacting “free” aminopropyl chains with restricted mobility, together with a small amount of protonated NH3+ groups. The concentration of the last-named species increased upon interaction with water, and this indicates reversible and fast proton exchange from water molecules to a fraction of the amino groups. Herein, this is discussed and explained for the first time, by a combination of experimental and theoretical approaches.

Investigating the Interaction of Water Vapour with Aminopropyl Groups on the Surface of Mesoporous Silica Nanoparticles

MUSSO, GIORGIA ELENA;BOTTINELLI, EMANUELA DIANA;BERLIER, Gloria
2017-01-01

Abstract

The interaction of water molecules with the surface of hybrid silica-based mesoporous materials is studied by 29Si, 1H and 13C solid-state NMR and IR spectroscopy, with the support of ab initio calculations. The surface of aminopropyl-grafted mesoporous silica nanoparticles is studied in the dehydrated state and upon interaction with controlled doses of water vapour. Former investigations described the interactions between aminopropyl and residual SiOH groups; the present study shows the presence of hydrogen-bonded species (SiOH to NH2) and weakly interacting “free” aminopropyl chains with restricted mobility, together with a small amount of protonated NH3+ groups. The concentration of the last-named species increased upon interaction with water, and this indicates reversible and fast proton exchange from water molecules to a fraction of the amino groups. Herein, this is discussed and explained for the first time, by a combination of experimental and theoretical approaches.
2017
18
7
839
849
http://pubs.rsc.org/en/Content/ArticleLanding/2015/CP/C5CP00552C#!divAbstract
density functional calculations; hydration; mesoporous materials; NMR spectroscopy; surface chemistry; Atomic and Molecular Physics, and Optics; Physical and Theoretical Chemistry
Paul, Geo; Musso, Giorgia Elena; Bottinelli, Emanuela; Cossi, Maurizio; Marchese, Leonardo; Berlier, Gloria
File in questo prodotto:
File Dimensione Formato  
Paul ChemPhysChem 17 reprint.pdf

Accesso riservato

Tipo di file: PDF EDITORIALE
Dimensione 2.32 MB
Formato Adobe PDF
2.32 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Amino NMR OA.pdf

Open Access dal 22/03/2018

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 1.54 MB
Formato Adobe PDF
1.54 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1634601
Citazioni
  • ???jsp.display-item.citation.pmc??? 3
  • Scopus 20
  • ???jsp.display-item.citation.isi??? 19
social impact