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Aimeur MR, Kortobi YE, Legrand AP. Water Adsorption on Pyrogenic Silica Followed by 1H MAS NMR. J Colloid Interface Sci 1997; 194:434-9. [PMID: 9398426 DOI: 10.1006/jcis.1997.5126] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
On the surface of two commercial pyrogenic silicas (Degussa and Cabot), five resonances were identified on the basis of the chemical shift, homonuclear coupling (T2), and spin-lattice relaxation behavior (T1). In accordance with previous studies we observed three different types of silanol groups: (i) weakly coupled (long T2), water inaccessible, isolated "internal" silanols at 1.8 ppm; (ii) weakly coupled, external "free" silanols revealed upon dehydration at 2.5 ppm; and (iii) strongly coupled external hydrogen bound silanols with an unresolved broad resonance between 3 and 7 ppm. The resonance of water, whose position between 2.6 and 4.6 ppm depended on water content, corresponded to two unresolved species of slightly different T1. By equating this resonance to the weighted average of two distinct populations of water, we were able to distinguish the first layer of strongly hydrogen bound water at 2.7 ppm from liquid-like water at 5 ppm. The first layer is complete for water relative humidity as low as 3.6% and corresponds to a surface coverage of 4.75 H2O/nm2. If we assumed a cristobalite-based surface structure, this meant a 1:1 ratio between surface hydroxyls and the first layer of physisorbed water. This ratio was the same for the two silicas regardless of surface area. Copyright 1997 Academic Press. Copyright 1997Academic Press
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Chuang IS, Maciel GE. A Detailed Model of Local Structure and Silanol Hydrogen Bonding of Silica Gel Surfaces. J Phys Chem B 1997. [DOI: 10.1021/jp9629046] [Citation(s) in RCA: 207] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- I-Ssuer Chuang
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-0002
| | - Gary E. Maciel
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-0002
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Dorémieux-Morin C, Heeribout L, Dumousseaux C, Fraissard J, Hommel H, Legrand AP. Study of the Constitutive Superficial Water of Precipitated Amorphous Silicas using 1H NMR: Broad-Line at 4 K and HR MAS at 300 K. J Am Chem Soc 1996. [DOI: 10.1021/ja962057k] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C. Dorémieux-Morin
- Contribution from the Laboratoire de Chimie des Surfaces, Université P. et M. Curie, Unité associée au CNRS - URA 1428, Casier 196, 4, place Jussieu, F 75252 Paris Cédex 05, France, and Laboratoire de Physique Quantique, ESPCI, Unité associée au CNRS - URA 1428, 10, rue Vauquelin, F 75005 Paris, France
| | - L. Heeribout
- Contribution from the Laboratoire de Chimie des Surfaces, Université P. et M. Curie, Unité associée au CNRS - URA 1428, Casier 196, 4, place Jussieu, F 75252 Paris Cédex 05, France, and Laboratoire de Physique Quantique, ESPCI, Unité associée au CNRS - URA 1428, 10, rue Vauquelin, F 75005 Paris, France
| | - C. Dumousseaux
- Contribution from the Laboratoire de Chimie des Surfaces, Université P. et M. Curie, Unité associée au CNRS - URA 1428, Casier 196, 4, place Jussieu, F 75252 Paris Cédex 05, France, and Laboratoire de Physique Quantique, ESPCI, Unité associée au CNRS - URA 1428, 10, rue Vauquelin, F 75005 Paris, France
| | - J. Fraissard
- Contribution from the Laboratoire de Chimie des Surfaces, Université P. et M. Curie, Unité associée au CNRS - URA 1428, Casier 196, 4, place Jussieu, F 75252 Paris Cédex 05, France, and Laboratoire de Physique Quantique, ESPCI, Unité associée au CNRS - URA 1428, 10, rue Vauquelin, F 75005 Paris, France
| | - H. Hommel
- Contribution from the Laboratoire de Chimie des Surfaces, Université P. et M. Curie, Unité associée au CNRS - URA 1428, Casier 196, 4, place Jussieu, F 75252 Paris Cédex 05, France, and Laboratoire de Physique Quantique, ESPCI, Unité associée au CNRS - URA 1428, 10, rue Vauquelin, F 75005 Paris, France
| | - A. P. Legrand
- Contribution from the Laboratoire de Chimie des Surfaces, Université P. et M. Curie, Unité associée au CNRS - URA 1428, Casier 196, 4, place Jussieu, F 75252 Paris Cédex 05, France, and Laboratoire de Physique Quantique, ESPCI, Unité associée au CNRS - URA 1428, 10, rue Vauquelin, F 75005 Paris, France
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55
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Affiliation(s)
- Changhua C. Liu
- Contribution from the Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Gary E. Maciel
- Contribution from the Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
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Vidal V, Théolier A, Thivolle-Cazat J, Basset JM, Corker J. Synthesis, Characterization, and Reactivity, in the C−H Bond Activation of Cycloalkanes, of a Silica-Supported Tantalum(III) Monohydride Complex: (⋮SiO)2TaIII−H. J Am Chem Soc 1996. [DOI: 10.1021/ja953524l] [Citation(s) in RCA: 132] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Véronique Vidal
- Contribution from the Laboratoire de Chimie Organométallique de Surface, UMR CNRS-CPE 9986, 43, Bd du 11 Novembre 1918, 69616 Villeurbanne Cédex, France, and Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, U.K
| | - Albert Théolier
- Contribution from the Laboratoire de Chimie Organométallique de Surface, UMR CNRS-CPE 9986, 43, Bd du 11 Novembre 1918, 69616 Villeurbanne Cédex, France, and Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, U.K
| | - Jean Thivolle-Cazat
- Contribution from the Laboratoire de Chimie Organométallique de Surface, UMR CNRS-CPE 9986, 43, Bd du 11 Novembre 1918, 69616 Villeurbanne Cédex, France, and Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, U.K
| | - Jean-Marie Basset
- Contribution from the Laboratoire de Chimie Organométallique de Surface, UMR CNRS-CPE 9986, 43, Bd du 11 Novembre 1918, 69616 Villeurbanne Cédex, France, and Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, U.K
| | - Judith Corker
- Contribution from the Laboratoire de Chimie Organométallique de Surface, UMR CNRS-CPE 9986, 43, Bd du 11 Novembre 1918, 69616 Villeurbanne Cédex, France, and Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, U.K
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57
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Affiliation(s)
- Changhua C. Liu
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Gary E. Maciel
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
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58
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I-Ssuer Chuang and, Maciel GE. Probing Hydrogen Bonding and the Local Environment of Silanols on Silica Surfaces via Nuclear Spin Cross Polarization Dynamics. J Am Chem Soc 1996. [DOI: 10.1021/ja951550d] [Citation(s) in RCA: 137] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- I-Ssuer Chuang and
- Contribution from the Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-0002
| | - Gary E. Maciel
- Contribution from the Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-0002
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