Skip to Main content Skip to Navigation
Journal articles

Solid-State NMR Characterization of the Surfactant−Silica Interface in Templated Silicas:  Acidic versus Basic Conditions

Abstract : A combination of one-dimensional and two-dimensional solid-state magic angle spinning nuclear magnetic resonance (MAS NMR) experiments has been used to investigate the hybrid organic−inorganic interfaces in surfactant templated silicas. Samples prepared with cetyltrimethylammonium bromide (CTAB) under acidic (HCl) and basic (NaOH) conditions have been compared. The use of sequences based on the 29Si-1H heteronuclear dipolar interactions allows us to selectively filter the NMR response of the protons close to the Si surface sites showing directly the clear difference between the two systems. The basic sample is characterized by a small amount of Si−OH groups and a short distance between the Si−O- surface groups and the surfactant polar head group, while the acidic sample exhibits a silanol-rich surface with a longer distance between the Si surface sites and the polar head groups. The nature of the interface induces consequent differences in the structure of the adsorbed water layers present at the interface, and this has been revealed by near-infrared experiments, as well as 1H MAS NMR spectra recorded on dehydrated and partially rehydrated samples. One objective of this work was also to show that the use of standard solid-state NMR conditions (magnetic field of 7 T and magic angle spinning frequency of less than 15 kHz) can be largely sufficient to obtain extremely valuable information regarding the silica−surfactant interfaces.
Document type :
Journal articles
Complete list of metadatas

Cited literature [11 references]  Display  Hide  Download

https://hal.sorbonne-universite.fr/hal-01455158
Contributor : Gestionnaire Hal-Upmc <>
Submitted on : Friday, February 3, 2017 - 12:57:09 PM
Last modification on : Wednesday, September 23, 2020 - 4:34:24 AM
Long-term archiving on: : Friday, May 5, 2017 - 11:13:02 AM

File

10.1021-cm062545j.pdf
Files produced by the author(s)

Identifiers

Citation

Niki Baccile, Guillaume Laurent, Christian Bonhomme, Plinio Innocenzi, Florence Babonneau. Solid-State NMR Characterization of the Surfactant−Silica Interface in Templated Silicas:  Acidic versus Basic Conditions. Chemistry of Materials, American Chemical Society, 2007, 19 (6), pp.1343-1354. ⟨10.1021/cm062545j⟩. ⟨hal-01455158⟩

Share

Metrics

Record views

204

Files downloads

632