Humidity and temperature effects on CTAB-templated mesophase silicate films at the air-liquid interface
Fernandez-Martin, Cristina ; Edler, Karen J. LU
and Roser, Stephen J.
(2004)
In Langmuir
20(24).
p.10679-10684
- Abstract
Off-specular X-ray reflectivity measurements were carried out to follow the in situ development of surfactant-templated silica thin films at the air-water interface under conditions of controlled relative humidity and temperature, using an enclosed sample cell designed for this purpose. The results suggest a strong dependence of formation time and growth mechanism on ambient conditions. Thin films were synthesized at the air-water interface using cetyltrimethylammonium bromide (CTAB, 0.075 M) and a silica precursor, tetramethoxysilane (TMOS, 0.29-0.80 M) in an acidic medium. The studied humidity range was from 50 to 100%, the temperature was between 25 and 40°C, and the TMOS/CTAB molar ratio was between 3.3 and 10.7. We observed that... (More)
Off-specular X-ray reflectivity measurements were carried out to follow the in situ development of surfactant-templated silica thin films at the air-water interface under conditions of controlled relative humidity and temperature, using an enclosed sample cell designed for this purpose. The results suggest a strong dependence of formation time and growth mechanism on ambient conditions. Thin films were synthesized at the air-water interface using cetyltrimethylammonium bromide (CTAB, 0.075 M) and a silica precursor, tetramethoxysilane (TMOS, 0.29-0.80 M) in an acidic medium. The studied humidity range was from 50 to 100%, the temperature was between 25 and 40°C, and the TMOS/CTAB molar ratio was between 3.3 and 10.7. We observed that high humidity slows down the growth process due to lack of evaporation. However, increasing the temperature results in a decrease in the film-formation time. We proposed a formation mechanism for film growth as a consequence of phase separation, organic array assembly, and silica polymerization.
(Less)
- author
- Fernandez-Martin, Cristina
; Edler, Karen J.
LU
and Roser, Stephen J.
- publishing date
- 2004-11-23
- type
- Contribution to journal
- publication status
- published
- in
- Langmuir
- volume
- 20
- issue
- 24
- pages
- 6 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- pmid:15544401
- scopus:10044243778
- ISSN
- 0743-7463
- DOI
- 10.1021/la048424k
- language
- English
- LU publication?
- no
- id
- 110b1b0f-fc1d-4e8a-a2e8-c9a386732799
- date added to LUP
- 2023-05-04 18:47:25
- date last changed
- 2024-01-05 01:14:08
@article{110b1b0f-fc1d-4e8a-a2e8-c9a386732799,
abstract = {{<p>Off-specular X-ray reflectivity measurements were carried out to follow the in situ development of surfactant-templated silica thin films at the air-water interface under conditions of controlled relative humidity and temperature, using an enclosed sample cell designed for this purpose. The results suggest a strong dependence of formation time and growth mechanism on ambient conditions. Thin films were synthesized at the air-water interface using cetyltrimethylammonium bromide (CTAB, 0.075 M) and a silica precursor, tetramethoxysilane (TMOS, 0.29-0.80 M) in an acidic medium. The studied humidity range was from 50 to 100%, the temperature was between 25 and 40°C, and the TMOS/CTAB molar ratio was between 3.3 and 10.7. We observed that high humidity slows down the growth process due to lack of evaporation. However, increasing the temperature results in a decrease in the film-formation time. We proposed a formation mechanism for film growth as a consequence of phase separation, organic array assembly, and silica polymerization.</p>}},
author = {{Fernandez-Martin, Cristina and Edler, Karen J. and Roser, Stephen J.}},
issn = {{0743-7463}},
language = {{eng}},
month = {{11}},
number = {{24}},
pages = {{10679--10684}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Langmuir}},
title = {{Humidity and temperature effects on CTAB-templated mesophase silicate films at the air-liquid interface}},
url = {{http://dx.doi.org/10.1021/la048424k}},
doi = {{10.1021/la048424k}},
volume = {{20}},
year = {{2004}},
}