| Records |
| Author |
Linssen, T.; Cassiers, K.; Cool, P.; Lebedev, O.; Whittaker, A.; Vansant, E.F. |
| Title |
Physicochemical and structural characterization of mesoporous aluminosilicates synthesized from leached saponite with additional aluminum incorporation |
Type |
A1 Journal article |
Year  |
2003 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
15 |
Issue |
25 |
Pages |
4863-4873 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
| Abstract |
A thorough investigation was performed on the physical (mechanical, thermal, and hydrothermal stability) and chemical (ion exchange capacity and silanol number) characteristics of aluminosilicate FSMs, synthesized via a new successful short-time synthesis route using leached saponite and a low concentration of CTAB. Moreover, the influence of an additional Al incorporation, utilizing different aluminum sources, on the structure of the FSM derived from saponite is studied. A mesoporous aluminosilicate with a low Si/Al ratio of 12.8 is synthesized, and still has a very large surface area of 1130 m(2)/g and pore volume of 0.92 cm(3)/g. The aluminum-containing samples all have a high cation exchange capacity of around 1 mmol/9 while they still have a silanol number of about 0.9 OH/nm(2); both characteristics being interesting for high-yield postsynthesis modification reactions. Finally, a study is performed on the transformation of the aluminosilicates into their Bronsted acid form via the exchange with ammonium ions and a consecutive heat treatment. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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| Language |
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Wos |
000187250800026 |
Publication Date |
2003-12-09 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.466 |
Times cited |
11 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 9.466; 2003 IF: 4.374 |
| Call Number |
UA @ lucian @ c:irua:103265 |
Serial |
2618 |
| Permanent link to this record |
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| Author |
Cassiers, K.; Linssen, T.; Aerts, K.; Cool, P.; Lebedev, O.; Van Tendeloo, G.; van Grieken, R.; Vansant, E.F. |
| Title |
Controlled formation of amine-templated mesostructured zirconia with remarkably high thermal stability |
Type |
A1 Journal article |
| Year |
2003 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
| Volume |
13 |
Issue |
|
Pages |
3033-3039 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
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| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Cambridge |
Editor |
|
| Language |
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Wos |
000186907500040 |
Publication Date |
2003-11-26 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
26 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:43522 |
Serial |
502 |
| Permanent link to this record |
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| |
| Author |
Cassiers, K.; van der Voort, P.; Linssen, T.; Vansant, E.F.; Lebedev, O.; van Landuyt, J. |
| Title |
A counterion-catalyzed (S0H+)(X-I+) pathway toward heat- and steam-stable mesostructured silica assembled from amines in acidic conditions |
Type |
A1 Journal article |
| Year |
2003 |
Publication |
The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical |
Abbreviated Journal |
J Phys Chem B |
| Volume |
107 |
Issue |
16 |
Pages |
3690-3696 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
| Abstract |
An alternative pathway to assemble mesoporous molecular sieve silicas is developed using nonionic alkylamines and N,N-dimethylalkylamines (SO) as structure-directing agents in acidic conditions. The synthesized mesostructures possess wormhole-like frameworks with pore sizes and pore volumes in the range of 20-90 Angstrom and 0.5-1.3 cm(3)/g, respectively. The formation of the mesophase is controlled by a counterion-mediated mechanism of the type (S(0)H(+))(X(-)I(+)), where S(0)H(+) are protonated water molecules that are hydrogen bonded to the lone electron pairs on the amine surfactant headgroups (S(0)H(+)), X(-) is the counteranion originating from the acid, and I(+) are the positively charged (protonated) silicate species. We found that the stronger the ion X(-) is bonded to S(0)H(+), the more it catalyzes the silica condensation into (S(0)H(+))(X(-)I(+)). Br(-) is shown to be a strong binding anion and therefore a fast silica polymerization promoter compared to Cl(-) resulting in the formation of a higher quality mesophase for the Br(-) syntheses. We also showed that the polymerization rate of the silica, dictated by the counterion, controls the morphology of the mesostructures from nonuniform agglomerated blocks in the case of Br(-) syntheses to spherical particles for the Cl(-) syntheses. Next to many benefits such as low temperature, short synthesis time, and the use of inexpensive, nontoxic, and easily extractable amine templates, the developed materials have a remarkable higher thermal and hydrothermal stability compared to hexagonal mesoporous silica, which is also prepared with nonionic amines but formed through the S(0)I(0) mechanism. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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| Language |
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Wos |
000182350200005 |
Publication Date |
2003-04-17 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1520-6106;1520-5207; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.177 |
Times cited |
9 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.177; 2003 IF: 3.679 |
| Call Number |
UA @ lucian @ c:irua:103300 |
Serial |
24 |
| Permanent link to this record |
| |
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| |
| Author |
Linssen, T.; Cool, P.; Baroudi, M.; Cassiers, K.; Vansant, E.F.; Lebedev, O.; van Landuyt, J. |
| Title |
Leached natural saponite as the silicate source in the synthesis of aluminosilicate hexagonal mesoporous materials |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical |
Abbreviated Journal |
J Phys Chem B |
| Volume |
106 |
Issue |
|
Pages |
4470-4476 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
| Abstract |
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| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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| Language |
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Wos |
000175356900019 |
Publication Date |
2002-07-26 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1520-6106;1520-5207; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.177 |
Times cited |
23 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.177; 2002 IF: 3.611 |
| Call Number |
UA @ lucian @ c:irua:46279 |
Serial |
1811 |
| Permanent link to this record |
