|
Records |
Links |
|
Author |
Geerts, L.; Geerts-Claes, H.; Skorikov, A.; Vermeersch, J.; Vanbutsele, G.; Galvita, V.; Constales, D.; Chandran, C.V.; Radhakrishnan, S.; Seo, J.W.; Breynaert, E.; Bals, S.; Sree, S.P.; Martens, J.A. |
|
|
Title |
Spherical core–shell alumina support particles for model platinum catalysts |
Type |
A1 Journal article |
|
Year |
2021 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
|
|
Volume |
13 |
Issue |
7 |
Pages |
4221-4232 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
γ- and δ-alumina are popular catalyst support materials. Using a hydrothermal synthesis method starting from aluminum nitrate and urea in diluted solution, spherical core–shell particles with a uniform particle size of about 1 μm were synthesized. Upon calcination at 1000 °C, the particles adopted a core–shell structure with a γ-alumina core and δ-alumina shell as evidenced by 2D and 3D electron microscopy and<sup>27</sup>Al magic angle spinning nuclear magnetic resonance spectroscopy. The spherical alumina particles were loaded with Pt nanoparticles with an average size below 1 nm using the strong electrostatic adsorption method. Electron microscopy and energy dispersive X-ray spectroscopy revealed a homogeneous platinum dispersion over the alumina surface. These platinum loaded alumina spheres were used as a model catalyst for bifunctional catalysis. Physical mixtures of Pt/alumina spheres and spherical zeolite particles are equivalent to catalysts with platinum deposited on the zeolite itself facilitating the investigation of the catalyst components individually. The spherical alumina particles are very convenient supports for obtaining a homogeneous distribution of highly dispersed platinum nanoparticles. Obtaining such a small Pt particle size is challenging on other support materials such as zeolites. The here reported and well-characterized Pt/alumina spheres can be combined with any zeolite and used as a bifunctional model catalyst. This is an interesting strategy for the examination of the acid catalytic function without the interference of the supported platinum metal on the investigated acid material. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000621767000026 |
Publication Date |
2021-01-21 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2040-3364 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
7.367 |
Times cited |
3 |
Open Access |
OpenAccess |
|
|
Notes |
Fonds Wetenschappelijk Onderzoek, G0A5417N G038116N ; Vlaamse regering, Methusalem ; Hercules Foundation, AKUL/13/19 ; |
Approved |
Most recent IF: 7.367 |
|
|
Call Number |
EMAT @ emat @c:irua:176021 |
Serial |
6679 |
|
Permanent link to this record |
|
|
|
|
Author |
Kirschhock, C.E.A.; Liang, D.; Van Tendeloo, G.; Fécant, A.; Hastoye, G.; Vanbutsele, G.; Bats, N.; Guillon, E.; Martens, J.A. |
|
|
Title |
Ordered end-member of ZSM-48 zeolite family |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
|
Volume |
21 |
Issue |
2 |
Pages |
371-380 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
ZSM-48 and related zeolites are considered to be highly disordered structures. Different polytypes can be clearly distinguished by simulation of high-resolution electron microscopy images. Synthesis of phase-pure polytypes was attempted. One of the investigated samples crystallized via seeding designated as COK-8 consisted of nanoscopic, needlelike crystals with a very large length/width ratio, growing along the pore direction. These specimens are phase-pure polytype 6 (PT6, numbering according to Lobo and van Koningsveld). Aggregates of these nanoneedles occasionally contained a second polytype: PT1. The latter polytype occurred more abundantly in larger crystal rods in an IZM-1 sample crystallized in ethylene glycol. Here too, the isolated crystallites mainly consist of large, defect-free regions of PT6. A simulation of polytype lattice energies offers a rational explanation for the observed polytypical intergrowth formation. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
|
Language |
|
Wos |
000262605200026 |
Publication Date |
2008-12-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
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 |
30 |
Open Access |
|
|
|
Notes |
Fwo; Goa |
Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
|
|
Call Number |
UA @ lucian @ c:irua:76032 |
Serial |
2503 |
|
Permanent link to this record |
|
|
|
|
Author |
Verheyen, E.; Jo, C.; Kurttepeli, M.; Vanbutsele, G.; Gobechiya, E.; Korányi, T.I.; Bals, S.; Van Tendeloo, G.; Ryoo, R.; Kirschhock, C.E.A.; Martens, J.A.; |
|
|
Title |
Molecular shape-selectivity of MFI zeolite nanosheets in n-decane isomerization and hydrocracking |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Journal of catalysis |
Abbreviated Journal |
J Catal |
|
|
Volume |
300 |
Issue |
|
Pages |
70-80 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
MFI zeolite nanosheets with thickness of 2 and 8 nm were synthesized, transformed into bifunctional catalysts by loading with platinum and tested in n-decane isomerization and hydrocracking. Detailed analysis of skeletal isomers and hydrocracked products revealed that the MFI nanosheets display transition-state shape-selectivity similar to bulk MFI zeolite crystals. The suppressed formation of bulky skeletal isomers and C5 cracking products are observed both in the nanosheets and the bulk crystals grown in three dimensions. This is typical for restricted transition-state shape-selectivity, characteristic for the MFI type pores. It is a first clear example of transition-state shape-selectivity inside a zeolitic nanosheet. Owing to the short diffusion path across the sheets, expression of diffusion-based discrimination of reaction products in the MFI nanosheets was limited. The 2-methylnonane formation among monobranched C10 isomers and 2,7-dimethyloctane among dibranched C10 isomers, which in MFI zeolite are favored by product diffusion, was much less favored on the nanosheets compared to the reference bulk ZSM-5 material. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
San Diego, Calif. |
Editor |
|
|
|
Language |
|
Wos |
000317558000009 |
Publication Date |
2013-02-07 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-9517; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
6.844 |
Times cited |
121 |
Open Access |
|
|
|
Notes |
Methusalem; IAP; Countatoms |
Approved |
Most recent IF: 6.844; 2013 IF: 6.073 |
|
|
Call Number |
UA @ lucian @ c:irua:106186 |
Serial |
2181 |
|
Permanent link to this record |