|
Title
|
|
|
|
Is there any microporosity in ordered mesoporous silicas?
| |
|
Author
|
|
|
|
| |
|
Abstract
|
|
|
|
| The porous structure of nanostructured silicas MCM-41 and SBA-15 has been characterized using N2 adsorption at 77 K, before and after n-nonane preadsorption, together with immersion calorimetry into liquids of different molecular dimensions. Selective blocking of the microporosity with n-nonane proves experimentally that MCM-41 is exclusively mesoporous while SBA-15 exhibits both micro- and mesopores. Additionally, N2 adsorption experiments on the preadsorbed samples show that the microporosity on SBA-15 is located in intrawall positions, the micropore volume accounting for only 7−8 % of the total pore volume. Calorimetric measurements into n-hexane (0.43 nm), 2-methylpentane (0.49 nm), and 2,2-dimethylbutane (0.56 nm) estimate the size of these micropores to be ¡Ü0.56 nm. |
| |
|
Language
|
|
|
|
English
| |
|
Source (journal)
|
|
|
|
Langmuir: the ACS journal of surfaces and colloids. - Washington, D.C.
| |
|
Publication
|
|
|
|
Washington, D.C.
:
2009
| |
|
ISSN
|
|
|
|
0743-7463
| |
|
DOI
|
|
|
|
10.1021/LA802692Z
| |
|
Volume/pages
|
|
|
|
25
:2
(2009)
, p. 939-943
| |
|
ISI
|
|
|
|
000262431100042
| |
|
Full text (Publisher's DOI)
|
|
|
|
| |
|