TU Darmstadt / ULB / TUbiblio

Hydrogen bonding of water confined in controlled-pore glass 10-75 studied by H-1-solid state NMR

Vyalikh, A. and Emmler, T. and Grünberg, B. and Xu, Y. and Shenderovich, I. and Findenegg, G. H. and Limbach, H. H. and Buntkowsky, G. (2007):
Hydrogen bonding of water confined in controlled-pore glass 10-75 studied by H-1-solid state NMR.
221, In: Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, (1), pp. 155-168, [Online-Edition: http://apps.webofknowledge.com/full_record.do?product=WOS&se...],
[Article]

Abstract

The adsorption of water in the mesoporous silica material with cylindrical pores of uniform diameter, Controlled Pore Glass 10-75 (CPG), was studied by H-1-MAS solid state NMR spectroscopy. From the NMR spectra it is evident that inside the mesopores of the silica different water environments exist, which are characterized by their individual chemical shift. All observed hydrogen atoms are either surface -SiOH groups or hydrogen bonded water molecules. It is found that there exist some stronger bound water molecules on the surface which are not removable even by heating at a vacuum pump. As a tentative assignment these water molecules are attributed to surface defects or inaccessible cavities in the CPG 10-75. At intermediate water filling levels, the principal signal is a single NMR line with continuously varying chemical shift. This finding is interpreted as the result of a radial water filling mechanism. That is, the filling of the pore grows from the pore surface towards the pore axis. Finally it is shown that water is a sensor for surface and structural inhomogeneity and that a coexistence of inner pore and outer bulk water exists in the system.

Item Type: Article
Erschienen: 2007
Creators: Vyalikh, A. and Emmler, T. and Grünberg, B. and Xu, Y. and Shenderovich, I. and Findenegg, G. H. and Limbach, H. H. and Buntkowsky, G.
Title: Hydrogen bonding of water confined in controlled-pore glass 10-75 studied by H-1-solid state NMR
Language: English
Abstract:

The adsorption of water in the mesoporous silica material with cylindrical pores of uniform diameter, Controlled Pore Glass 10-75 (CPG), was studied by H-1-MAS solid state NMR spectroscopy. From the NMR spectra it is evident that inside the mesopores of the silica different water environments exist, which are characterized by their individual chemical shift. All observed hydrogen atoms are either surface -SiOH groups or hydrogen bonded water molecules. It is found that there exist some stronger bound water molecules on the surface which are not removable even by heating at a vacuum pump. As a tentative assignment these water molecules are attributed to surface defects or inaccessible cavities in the CPG 10-75. At intermediate water filling levels, the principal signal is a single NMR line with continuously varying chemical shift. This finding is interpreted as the result of a radial water filling mechanism. That is, the filling of the pore grows from the pore surface towards the pore axis. Finally it is shown that water is a sensor for surface and structural inhomogeneity and that a coexistence of inner pore and outer bulk water exists in the system.

Journal or Publication Title: Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics
Volume: 221
Number: 1
Uncontrolled Keywords: hydrogen bonding water controlled pore glass 1h-nmr spectroscopy pore condensation mesoporous silica porous silica rabbit lens x-ray molecules h-1-nmr sba-15 mcm-41 ice diffraction
Divisions: 07 Department of Chemistry
07 Department of Chemistry > Physical Chemistry
Date Deposited: 27 Oct 2014 20:52
Official URL: http://apps.webofknowledge.com/full_record.do?product=WOS&se...
Additional Information:

131ME Times Cited:21 Cited References Count:34

Export:
Suche nach Titel in: TUfind oder in Google
Send an inquiry Send an inquiry

Options (only for editors)

View Item View Item