Home | << 1 2 3 >> |
Records | |||||
---|---|---|---|---|---|
Author | van Oers, C.J.; Kurttepeli, M.; Mertens, M.; Bals, S.; Meynen, V.; Cool, P. | ||||
Title | Zeolite \beta nanoparticles based bimodal structures : mechanism and tuning of the porosity and zeolitic properties | Type | A1 Journal article | ||
Year | 2014 | Publication | Microporous and mesoporous materials: zeolites, clays, carbons and related materials | Abbreviated Journal | Micropor Mesopor Mat |
Volume | 185 | Issue | Pages | 204-212 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Despite great efforts in the research area of zeolite nanoparticles and their use in the synthesis of bimodal materials, still little is known about the impact of the synthesis conditions of the zeolite nanoparticles on its own characteristics, and on the properties and the formation mechanism of the final bimodal materials. A zeolite β nanoparticles solution is applied in a mesotemplate-free synthesis method, and the influence of the hydrothermal ageing temperature of the nanoparticles solution on both the zeolitic and porosity characteristics of the final bimodal material has been studied. Transmission electron microscopy in combination with 3-dimensional reconstructions obtained by electron tomography revealed that the zeolite β nanoparticles are connected by neck-like structures, thus creating a wormhole-like mesoporous material. Considering the zeolitic properties, a clear threshold is observed in the synthesis temperature series at 413 K. Below and at this threshold, the biporous materials show no apparent zeolitic characteristics, although these materials exhibit a more condensed and uniform SiOSi network in comparison to Al-MCF. Synthesis temperatures above the threshold lead to bimodal structures with defined zeolitic properties. Moreover, the dimensions of the nanoparticles are studied by TEM, revealing an increasing particle size with increasing temperature under the threshold of 413 K, which is in agreement with a sol-mechanism. This mechanism is disturbed after the threshold due to the start of the crystallisation process. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000330930400025 | Publication Date | 2013-11-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1387-1811; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.615 | Times cited | 10 | Open Access | OpenAccess |
Notes | 262348 Esmi | Approved | Most recent IF: 3.615; 2014 IF: 3.453 | ||
Call Number | UA @ lucian @ c:irua:112501 | Serial | 3930 | ||
Permanent link to this record | |||||
Author | van Oers, C.J.; Stevens, W.J.J.; Bruijn, E.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Meynen, V.; Cool, P. | ||||
Title | Formation of a combined micro- and mesoporous material using zeolite Beta nanoparticles | Type | A1 Journal article | ||
Year | 2009 | Publication | Microporous and mesoporous materials: zeolites, clays, carbons and related materials | Abbreviated Journal | Micropor Mesopor Mat |
Volume | 120 | Issue | 1/2 | Pages | 29-34 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Composite micro- and mesoporous materials are synthesized using zeolite Beta nanoparticles without the need for a structure directing agent to form the mesopores. This leads to important ecological and economical advantages. The influence of the way of cooling the aged nanoparticles solution on the formation of the composite materials has been studied. The materials have been characterized towards porosity by N2-sorption, towards zeolitic properties by TGA, DRIFT, XRD and TEM, towards aluminium content by EPMA. All prepared structures possess zeolitic properties. However, the method of cooling down of the aged seeds leads to differences in the porosity and intensity of the zeolitic characteristics. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000264619200006 | Publication Date | 2008-09-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1387-1811; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.615 | Times cited | 42 | Open Access | |
Notes | Crp; Sfr Ua | Approved | Most recent IF: 3.615; 2009 IF: 2.652 | ||
Call Number | UA @ lucian @ c:irua:74950 | Serial | 1254 | ||
Permanent link to this record | |||||
Author | Van Tendeloo, G.; Lebedev, O.I.; Collart, O.; Cool, P.; Vansant, E.F. | ||||
Title | Structure of nanoscale mesoporous silica spheres? | Type | A1 Journal article | ||
Year | 2003 | Publication | Journal of physics : condensed matter | Abbreviated Journal | J Phys-Condens Mat |
Volume | 15 | Issue | Pages | S3037-S3046 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | |||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | London | Editor | ||
Language | Wos | Publication Date | 0000-00-00 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0953-8984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.649 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 2.649; 2003 IF: 1.757 | |||
Call Number | UA @ lucian @ c:irua:46265 | Serial | 3313 | ||
Permanent link to this record | |||||
Author | Verbruggen, S.W.; Ribbens, S.; Tytgat, T.; Hauchecorne, B.; Smits, M.; Meynen, V.; Cool, P.; Martens, J.A.; Lenaerts, S. | ||||
Title | The benefit of glass bead supports for efficient gas phase photocatalysis : case study of a commercial and a synthesised photocatalyst | Type | A1 Journal article | ||
Year | 2011 | Publication | Chemical engineering journal | Abbreviated Journal | Chem Eng J |
Volume | 174 | Issue | 1 | Pages | 318-325 |
Keywords | A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | In the field of photocatalytic air purification, the immobilisation of catalyst particles on support surfaces without loss of photon efficiency is an important challenge. Therefore, an immobilisation method involving a one-step suspension coating of pre-synthesised photocatalysts on glass beads was applied. The various benefits are exemplified in the gas phase photodegradation of ethylene. Coating of glass beads is easy, fast, cheap and offers a more efficient alternative to bulk catalyst pellets. Furthermore, this coating procedure allows to use porous, pre-synthesised catalysts to their full potential, as the surface area and morphology of the initial powder is barely altered after coating, in strong contrast to pelletising. With this technique it became possible to study the gas phase photocatalytic activity of commercial titanium dioxide, trititanate nanotubes and mixed phase anatase/trititanate nanotubes in a packed bed reactor towards the degradation of ethylene without changing the catalyst properties. Coating of glass beads with the photocatalyst revealed the superior activity of the as-prepared nanotubes, compared to TiO2 Aerolyst® 7710 in gaseous phase. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000296950300041 | Publication Date | 2011-09-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947; 1873-3212 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.216 | Times cited | 39 | Open Access | |
Notes | ; The author wishes to acknowledge the Research Foundation of Flanders (FWO) for the financial support. Evonik is greatly thanked for supplying the TiO<INF>2</ INF> Aerolyst (R) 7710 pellets. ; | Approved | Most recent IF: 6.216; 2011 IF: 3.461 | ||
Call Number | UA @ admin @ c:irua:93364 | Serial | 5929 | ||
Permanent link to this record | |||||
Author | Vernimmen, J.; Guidotti, M.; Silvestre-Albero, J.; Jardim, E.O.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Psaro, R.; Rodríguez-Reinoso, F.; Meynen, V.; Cool, P. | ||||
Title | Immersion calorimetry as a tool to evaluate the catalytic performance of titanosilicate materials in the epoxidation of cyclohexene | Type | A1 Journal article | ||
Year | 2011 | Publication | Langmuir: the ACS journal of surfaces and colloids | Abbreviated Journal | Langmuir |
Volume | 27 | Issue | 7 | Pages | 3618-3625 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Different types of titanosilicates are synthesized, structurally characterized, and subsequently catalytically tested in the liquid-phase epoxidation of cyclohexene. The performance of three types of combined zeolitic/mesoporous materials is compared with that of widely studied Ti-grafted-MCM-41 molecular sieve and the TS-1 microporous titanosilicate. The catalytic test results are correlated with the structural characteristics of the different catalysts. Moreover, for the first time, immersion calorimetry with the same substrate molecule as in the catalytic test reaction is applied as an extra means to interpret the catalytic results. A good correlation between catalytic performance and immersion calorimetry results is found. This work points out that the combination of catalytic testing and immersion calorimetry can lead to important insights into the influence of the materials structural characteristics on catalysis. Moreover, the potential of using immersion calorimetry as a screening tool for catalysts in epoxidation reactions is shown. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000288970900054 | Publication Date | 2011-02-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0743-7463;1520-5827; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.833 | Times cited | 19 | Open Access | |
Notes | Approved | Most recent IF: 3.833; 2011 IF: 4.186 | |||
Call Number | UA @ lucian @ c:irua:88366 | Serial | 1557 | ||
Permanent link to this record | |||||
Author | Vernimmen, J.; Meynen, V.; Herregods, S.J.F.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P. | ||||
Title | New insights in the formation of combined zeolitic/mesoporous materials by using a one-pot templating synthesis | Type | A1 Journal article | ||
Year | 2011 | Publication | European journal of inorganic chemistry | Abbreviated Journal | Eur J Inorg Chem |
Volume | Issue | 27 | Pages | 4234-4240 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Zeolitic growth is often absent or occurs in separate phases when synthetic strategies based on the combination of zeolite templates and mesopore templating agents are applied. In this work, zeolitic growth and mesopore formation have been investigated at different temperatures by applying a one-pot templating approach, based on a TS-1 zeolite synthesis whereby part of the microtemplate (tetrapropylammonium hydroxide, TPAOH) is replaced by a mesotemplate (hexadecyltrimethylammonium bromide, CTMABr). Moreover, the synthesis duration and the molar ratio of the microtemplate/mesotemplate have also been studied. The different syntheses clearly show the inherent competitive mechanism between zeolitic growth and mesopore formation. These insights have led to the conclusion that by following a one-pot templating strategy with standard, nonexotic commercial templates, i.e. CTMABr and TPAOH, it is not possible to develop a true hierarchical mesoporous zeolite, meaning a mesoporous siliceous material with highly crystalline zeolitic walls. The resultant materials are instead combined zeolitic/mesoporous composite structures with, however, highly tuneable and controllable porosity characteristics. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000296143500014 | Publication Date | 2011-08-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1434-1948; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.444 | Times cited | 7 | Open Access | |
Notes | Fwo | Approved | Most recent IF: 2.444; 2011 IF: 3.049 | ||
Call Number | UA @ lucian @ c:irua:91574 | Serial | 2315 | ||
Permanent link to this record | |||||
Author | Vernimmen, J.; Meynen, V.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P. | ||||
Title | Formation of a Ti-siliceous trimodal material with macroholes, mesopores and zeolitic features via a one-pot templating synthesis | Type | A1 Journal article | ||
Year | 2012 | Publication | Journal of porous materials | Abbreviated Journal | J Porous Mat |
Volume | 19 | Issue | 2 | Pages | 153-160 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Based on a facile one-pot templating synthesis, using a TS-1 zeolite recipe whereby part of the zeolite structure directing agent is replaced by a mesopore templating agent, a trimodal material is formed. The resulting meso-TSM material combines mesoporosity (Ti-MCM-41) with zeolitic features (TS-1) and a unique sheet-like morphology with uniform macroporous voids (macroholes). Moreover, the macrohole formation, mesoporosity and zeolitic properties of the meso-TSM material can be controlled in a straightforward way by adjusting the length of the hydrothermal treatment. This newly developed material may imply great potential for catalytic redox applications and diffusion limitated processes because of its highly tunable character in all three dimensions (micro-, meso- and macroporous scale). | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Kluwer Academic | Place of Publication | Boston, Mass. | Editor | |
Language | Wos | 000301187600002 | Publication Date | 2011-03-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1380-2224;1573-4854; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.624 | Times cited | 2 | Open Access | |
Notes | Fwo; Goa | Approved | Most recent IF: 1.624; 2012 IF: 1.348 | ||
Call Number | UA @ lucian @ c:irua:88367 | Serial | 1257 | ||
Permanent link to this record | |||||
Author | Volders, J.; Elen, K.; Raes, A.; Ninakanti, R.; Kelchtermans, A.-S.; Sastre, F.; Hardy, A.; Cool, P.; Verbruggen, S.W.; Buskens, P.; Van Bael, M.K. | ||||
Title | Sunlight-powered reverse water gas shift reaction catalysed by plasmonic Au/TiO₂ nanocatalysts : effects of Au particle size on the activity and selectivity | Type | A1 Journal article | ||
Year | 2022 | Publication | Nanomaterials | Abbreviated Journal | Nanomaterials-Basel |
Volume | 12 | Issue | 23 | Pages | 4153-13 |
Keywords | A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | This study reports the low temperature and low pressure conversion (up to 160 °C, p = 3.5 bar) of CO2 and H2 to CO using plasmonic Au/TiO2 nanocatalysts and mildly concentrated artificial sunlight as the sole energy source (up to 13.9 kW·m-2 = 13.9 suns). To distinguish between photothermal and non-thermal contributors, we investigated the impact of the Au nanoparticle size and light intensity on the activity and selectivity of the catalyst. A comparative study between P25 TiO2-supported Au nanocatalysts of a size of 6 nm and 16 nm displayed a 15 times higher activity for the smaller particles, which can only partially be attributed to the higher Au surface area. Other factors that may play a role are e.g., the electronic contact between Au and TiO2 and the ratio between plasmonic absorption and scattering. Both catalysts displayed ≥84% selectivity for CO (side product is CH4). Furthermore, we demonstrated that the catalytic activity of Au/TiO2 increases exponentially with increasing light intensity, which indicated the presence of a photothermal contributor. In dark, however, both Au/TiO2 catalysts solely produced CH4 at the same catalyst bed temperature (160 °C). We propose that the difference in selectivity is caused by the promotion of CO desorption through charge transfer of plasmon generated charges (as a non-thermal contributor). | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000896093900001 | Publication Date | 2022-11-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2079-4991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.3 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 5.3 | |||
Call Number | UA @ admin @ c:irua:191843 | Serial | 7341 | ||
Permanent link to this record | |||||
Author | Zhuge, X.; Jinnai, H.; Dunin-Borkowski, R.E.; Migunov, V.; Bals, S.; Cool, P.; Bons, A.-J.; Batenburg, K.J. | ||||
Title | Automated discrete electron tomography – Towards routine high-fidelity reconstruction of nanomaterials | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 175 | Issue | 175 | Pages | 87-96 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Electron tomography is an essential imaging technique for the investigation of morphology and 3D structure of nanomaterials. This method, however, suffers from well-known missing wedge artifacts due to a restricted tilt range, which limits the objectiveness, repeatability and efficiency of quantitative structural analysis. Discrete tomography represents one of the promising reconstruction techniques for materials science, potentially capable of delivering higher fidelity reconstructions by exploiting the prior knowledge of the limited number of material compositions in a specimen. However, the application of discrete tomography to practical datasets remains a difficult task due to the underlying challenging mathematical problem. In practice, it is often hard to obtain consistent reconstructions from experimental datasets. In addition, numerous parameters need to be tuned manually, which can lead to bias and non-repeatability. In this paper, we present the application of a new iterative reconstruction technique, named TVR-DART, for discrete electron tomography. The technique is capable of consistently delivering reconstructions with significantly reduced missing wedge artifacts for a variety of challenging data and imaging conditions, and can automatically estimate its key parameters. We describe the principles of the technique and apply it to datasets from three different types of samples acquired under diverse imaging modes. By further reducing the available tilt range and number of projections, we show that the proposed technique can still produce consistent reconstructions with minimized missing wedge artifacts. This new development promises to provide the electron microscopy community with an easy-to-use and robust tool for high-fidelity 3D characterization of nanomaterials. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000403342500008 | Publication Date | 2017-01-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 22 | Open Access | OpenAccess |
Notes | This work has been supported in part by the Stichting voor de Technische Wetenschappen (STW) through a personal grant (Veni,13610), and was in part by ExxonMobil Chemical Europe Inc. The authors further acknowledge financial support from the University of Antwerp through BOF GOA funding. S.B. acknowledges financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). R.D.B. is grateful for funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007–2013)/ ERC grant agreement number 320832. Thomas Altantzis is gratefully acknowledged for acquiring the Anatase nanosheets dataset. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:141218UA @ admin @ c:irua:141218 | Serial | 4485 | ||
Permanent link to this record |