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Evolution of structure and composition during the synthesis of mesoporous silica SBA-15 studied by small-angle neutron scattering

Linton, Peter LU ; Rennie, Adrian R. and Alfredsson, Viveka LU (2011) In Solid State Sciences 13(4). p.793-799
Abstract
In-situ time-resolved small-angle neutron scattering (SANS) has been applied for the study of the formation of mesoporous silica SBA-15. The advantage of neutron scattering, compared to X-ray scattering, is the possibility to contrast match i.e. highlight certain parts of the sample. Three different solvents with different scattering contrasts were used for each synthesis. Three different silica sources (tetramethyl orthosilicate, tetraethyl orthosilicate and tetrapropyl orthosilicate) were used and in three cases salts (sodium chloride or sodium bromide) were added prior to addition of the silica source. Hence, the effect of the silica sources and of the salts, on the formation of SBA-15 was investigated. The main focus was on the... (More)
In-situ time-resolved small-angle neutron scattering (SANS) has been applied for the study of the formation of mesoporous silica SBA-15. The advantage of neutron scattering, compared to X-ray scattering, is the possibility to contrast match i.e. highlight certain parts of the sample. Three different solvents with different scattering contrasts were used for each synthesis. Three different silica sources (tetramethyl orthosilicate, tetraethyl orthosilicate and tetrapropyl orthosilicate) were used and in three cases salts (sodium chloride or sodium bromide) were added prior to addition of the silica source. Hence, the effect of the silica sources and of the salts, on the formation of SBA-15 was investigated. The main focus was on the evolution of the ordered hexagonal structure i.e. investigation of the (10) Bragg peak. In synchrotron SAXS measurements the intensity of the (10) Bragg peak continuously increases during the measurement. However, in the SANS measurements the (10) Bragg peak area decreases with time. The decrease of the (10) peak is highly dependent on the solvent, a larger fraction of D2O in the solvent results in a bigger reduction. The decrease is also more pronounced when salt is present in the synthesis. The reduction of intensity reflects the chemistry in the wall and is explained by the compositional change in the wall during the maturation of the hexagonal order. (C) 2010 Elsevier Masson SAS. All rights reserved. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
SBA-15, Mesoporous, SANS, In-situ, Formation, Pluronic, Synthesis
in
Solid State Sciences
volume
13
issue
4
pages
793 - 799
publisher
Editions scientifiques Elsevier
external identifiers
  • wos:000289965900017
  • scopus:79953058057
ISSN
1873-3085
DOI
10.1016/j.solidstatesciences.2010.02.035
language
English
LU publication?
yes
id
20e2cc5f-6e58-426b-a046-927a1ddfcb80 (old id 1987072)
date added to LUP
2011-06-29 09:41:06
date last changed
2017-11-12 03:10:12
@article{20e2cc5f-6e58-426b-a046-927a1ddfcb80,
  abstract     = {In-situ time-resolved small-angle neutron scattering (SANS) has been applied for the study of the formation of mesoporous silica SBA-15. The advantage of neutron scattering, compared to X-ray scattering, is the possibility to contrast match i.e. highlight certain parts of the sample. Three different solvents with different scattering contrasts were used for each synthesis. Three different silica sources (tetramethyl orthosilicate, tetraethyl orthosilicate and tetrapropyl orthosilicate) were used and in three cases salts (sodium chloride or sodium bromide) were added prior to addition of the silica source. Hence, the effect of the silica sources and of the salts, on the formation of SBA-15 was investigated. The main focus was on the evolution of the ordered hexagonal structure i.e. investigation of the (10) Bragg peak. In synchrotron SAXS measurements the intensity of the (10) Bragg peak continuously increases during the measurement. However, in the SANS measurements the (10) Bragg peak area decreases with time. The decrease of the (10) peak is highly dependent on the solvent, a larger fraction of D2O in the solvent results in a bigger reduction. The decrease is also more pronounced when salt is present in the synthesis. The reduction of intensity reflects the chemistry in the wall and is explained by the compositional change in the wall during the maturation of the hexagonal order. (C) 2010 Elsevier Masson SAS. All rights reserved.},
  author       = {Linton, Peter and Rennie, Adrian R. and Alfredsson, Viveka},
  issn         = {1873-3085},
  keyword      = {SBA-15,Mesoporous,SANS,In-situ,Formation,Pluronic,Synthesis},
  language     = {eng},
  number       = {4},
  pages        = {793--799},
  publisher    = {Editions scientifiques Elsevier},
  series       = {Solid State Sciences},
  title        = {Evolution of structure and composition during the synthesis of mesoporous silica SBA-15 studied by small-angle neutron scattering},
  url          = {http://dx.doi.org/10.1016/j.solidstatesciences.2010.02.035},
  volume       = {13},
  year         = {2011},
}