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	Author	Corthals, S.; van Noyen, J.; Liang, D.; Ke, X.; Van Tendeloo, G.; Jacobs, P.; Sels, B.
	Title	A cyclic catalyst pretreatment in CO₂ for high yield production of Carbon nanofibers with narrow diameter distribution			Type	A1 Journal article
	Year	2011	Publication	Catalysis letters	Abbreviated Journal	Catal Lett
	Volume	141	Issue	11	Pages	1621-1624
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	This paper presents a cyclic catalyst pretreatment process to improve the CNF yield with narrow size distribution by sequentially feeding the CVD reactor with CH4/CO2 mixtures (carbon deposition) and CO2 (carbon removal) prior to the actual growth process. A mechanism based on a break-up of large Ni particles tentatively explains the beneficial effect of the cyclic carbon deposition/removal CVD procedure.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Basel	Editor
	Language		Wos	000296471400006	Publication Date	2011-09-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1011-372X;1572-879X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.799	Times cited	1	Open Access
	Notes	Iwt; Iap			Approved	Most recent IF: 2.799; 2011 IF: 2.242
	Call Number	UA @ lucian @ c:irua:91888			Serial	598
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	Author	de Clippel, F.; Harkiolakis, A.; Vosch, T.; Ke, X.; Giebeler, L.; Oswald, S.; Houthoofd, K.; Jammaer, J.; Van Tendeloo, G.; Martens, J.A.; Jacobs, P.A.; Baron, G.V.; Sels, B.F.; Denayer, J.F.M.
	Title	Graphitic nanocrystals inside the pores of mesoporous silica : synthesis, characterization and an adsorption study			Type	A1 Journal article
	Year	2011	Publication	Microporous and mesoporous materials: zeolites, clays, carbons and related materials	Abbreviated Journal	Micropor Mesopor Mat
	Volume	144	Issue	1/3	Pages	120-133
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	This work presents a new carbonsilica hybrid material, denoted as CSM, with remarkable sorption properties. It consists of intraporous graphitic nanocrystals grown in the pores of mesoporous silica. CSM is obtained by a subtle incipient wetness impregnation of Al-containing mesoporous silica with furfuryl alcohol (FA)/hemelitol solutions. Both the volume match of the impregnation solution with that of the silica template pore volume, and the presence of Al3+ in the silica, are crucial to polymerize FA selectively inside the mesopores. Carbonization of the intraporous polymer was then performed by pyrolysis under He up to 1273 K. The resulting CSMs were examined by SEM, HRTEM, 27Al MAS NMR, N2 adsorption, XRD, TGA, TPD, XPS, pycnometry and Raman spectroscopy. Mildly oxidized graphitic-like carbon nanoblocks, consisting of a few graphene-like sheets, were thus identified inside the template mesopores. Random stacking of these carbon crystallites generates microporosity resulting in biporous materials at low carbon content and microporous materials at high carbon loadings. Very narrow pore distributions were obtained when pyrolysis was carried out under slow heating rate, viz. 1 K min−1. Adsorption and shape selective properties of the carbon filled mesoporous silica were studied by performing pulse chromatography and breakthrough experiments, and by measuring adsorption isotherms of linear and branched alkanes. Whereas the parent mesoporous silica shows unselective adsorption, their CSM analogues preferentially adsorb linear alkanes. The sorption capacity and selectivity can be adjusted by changing the pore size of the template or by varying the synthesis conditions. A relation between the carbon crystallites size and the shape selective behaviour of the corresponding CSM for instance is demonstrated. Most interestingly, CSM shows separation factors for linear and branched alkanes up to values comparable to those of zeolitic molecular sieves.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000293435400016	Publication Date	2011-04-15
	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	15	Open Access
	Notes				Approved	Most recent IF: 3.615; 2011 IF: 3.285
	Call Number	UA @ lucian @ c:irua:92325			Serial	1380
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	Author	Peng, L.; Philippaerts, A.; Ke, X.; van Noyen, J.; de Cleppel, F.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F.
	Title	Preparation of sulfonated ordered mesoporous carbon and its use for the esterification of fatty acids			Type	A1 Journal article
	Year	2010	Publication	Catalysis today	Abbreviated Journal	Catal Today
	Volume	150	Issue	1/2	Pages	140-146
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Mesoporous carbon, which can be replicated from mesoporous silica and whose surface is hydrophobic, can be an ideal catalyst for the esterification of fatty acids. Here we report an easy and low cost way to prepare sulfonic acid group-functionalized mesoporous carbon. A sample of calcined mesoporous silica SBA-15 was added to an aqueous sucrose solution followed by drying and calcination at different temperatures. In contrast to existing procedures, the obtained hybrid Si/C material was then first sulfonated in H2SO4, before the final removal of the silica template in order to stabilize the porous structure towards the liquid phase sulfonation treatment. Thus the silicacarbon composites, instead of the mesoporous carbon, were successfully sulfonated to introduce SO3H groups, while keeping the ordered mesoporous structure intact. The influence of carbonization temperature was investigated, suggesting an optimum temperature of 873 K. The SO3H group-functionalized mesoporous carbon, denoted as CMK-3-873-SO3H, was characterized by means of XRD, N2 physisorption, SEM, FT-IR, elemental analysis and TEM. It followed that a uniform mesoporous carbon was obtained with an average pore size of 3.89 nm, a specific surface of 807 m2/g and a SO3H group loading of 0.39 meq/g of dry material. Compared with other solid acid catalysts, the resulting material shows enhanced activity in the acid-catalyzed esterification of oleic acid with methanol, and can be used repeatedly. The increased catalytic performance is attributed to the hydrophobic surface and larger pore size of the new catalyst. It can effectively accommodate long chain fatty acids and reject formed water, making the active sites easily accessible.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000275566700024	Publication Date	2009-09-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0920-5861;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.636	Times cited	132	Open Access
	Notes				Approved	Most recent IF: 4.636; 2010 IF: 2.993
	Call Number	UA @ lucian @ c:irua:81739			Serial	2706
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	Author	Ribbens, S.; Beyers, E.; Schellens, K.; Mertens, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; Meynen, V.; Cool, P.
	Title	Systematic evaluation of thermal and mechanical stability of different commercial and synthetic photocatalysts in relation to their photocatalytic activity			Type	A1 Journal article
	Year	2012	Publication	Microporous and mesoporous materials: zeolites, clays, carbons and related materials	Abbreviated Journal	Micropor Mesopor Mat
	Volume	156	Issue		Pages	62-72
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
	Abstract	The effect of thermal treatment and mechanical stress on the structural and photocatalytic properties of eight different (synthetic and commercial) photocatalysts has been thoroughly investigated. Different mesoporous Ti-based materials were prepared via surfactant based synthesis routes (e.g. Pluronic 123, CTMABr = Cetyltrimethylammonium bromide) or via template-free synthesis routes (e.g. trititanate nanotubes). Also, the stabilizing effect of the NaOH/NH4OH post-treatment on the templated mesoporous materials and their photocatalytic activity was investigated. Furthermore, the thermal and mechanical properties of commercially available titanium dioxides such as P25 Evonik® and Millenium PC500® were studied. The various photocatalysts were analyzed with N2-sorption, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) to obtain information concerning the specific surface area, pore volume, crystal structure, morphology, phase transitions, etc. In general, results show that the NaOH post-treatment leads to an increased control of the crystallization process during calcination resulting in a higher thermal stability, but at the same time diminishes the photocatalytic activity. Mesoporous materials in which pre-synthesized nanoparticles are used as titania source have the best mechanical stability whereas the mechanical stability of the nanotubes is the most limited. At increased temperatures and pressures, the tested commercial titanium dioxides lose their superior photocatalytic activity caused by a decreased accessibility of the active sites. The observed changes in adsorption capacities and photocatalytic activities cannot be assigned to one single phenomenon. In this respect, it shows the need to define a general/standard method to compare different photocatalysts. Furthermore, it is shown that the photocatalytic properties do not necessarily deteriorate under thermal stress, but can be improved due to crystallization, even though the initial material is (partially) destroyed. It is shown that the usefulness of a specific type of photocatalyst strongly depends on the application and the temperature/pressure to which it needs to resist.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000303625200010	Publication Date	2012-02-08
	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	8	Open Access
	Notes	Fwo			Approved	Most recent IF: 3.615; 2012 IF: 3.365
	Call Number	UA @ lucian @ c:irua:96910			Serial	3466
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	Author	Liu, J.; Hu, Z.-Y.; Peng, Y.; Huang, H.-W.; Li, Y.; Wu, M.; Ke, X.-X.; Van Tendeloo, G.; Su, B.-L.
	Title	2D ZnO mesoporous single-crystal nanosheets with exposed {0001} polar facets for the depollution of cationic dye molecules by highly selective adsorption and photocatalytic decomposition			Type	A1 Journal article
	Year	2016	Publication	Applied catalysis : B : environmental	Abbreviated Journal	Appl Catal B-Environ
	Volume	181	Issue	181	Pages	138-145
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Two dimensional (2D) ZnO nanosheets are ideal system for dimensionally confined transport phenomenon investigation owing to specific surface atomic configuration. Therefore, 2D ZnO porous nanosheets with single-crystal nature and {0001} polar facets, likely display some specific physicochemical properties. In this work, for the first time, 2D ZnO mesoporous single-crystal nanosheets (ZnO-MSN) with {0001} polar facets have been designed and prepared via an intriguing colloidal templating approach through controlling the infiltration speed for the suspension of EG-capped ZnO nanoparticles and polymer colloids. The EG-capped ZnO nanoparticles are very helpful for single-crystal nanosheet formation, while the polymer colloids play dual roles on the mesoporosity generation and {0001} polar facets formation within the mesopores. Such special 2D structure not only accelerates the hole-electron separation and the electron transportation owing to the single-crystal nature, but also enhances the selective adsorption of organic molecules owing to the porous structure and the exposed {0001} polar facets with more O-termination (000-1) surfaces: the 2D ZnO-MSN shows highly selective adsorption and significantly higher photodegradation for positively charged rhodamine B than those for negatively charged methyl orange and neutral phenol, comparing with ZnO nanoparticles (ZnO-NP) and ZnO commercial nanoparticles (ZnO-CNP) with high surface areas. This work may shed some light on better understanding the synthesis of 2D porous single-crystal nanosheet with exposed polar surfaces and photocatalytic mechanism of nanostructured semiconductors in a mixed organic molecules system.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000364256000015	Publication Date	2015-08-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0926-3373;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.446	Times cited	60	Open Access
	Notes	246791 Countatoms			Approved	Most recent IF: 9.446
	Call Number	c:irua:127638 c:irua:127638 c:irua:127638			Serial	10
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	Author	Chemchuen, S.; Zhou, K.; Kabir, N.A.; Chen, Y.; Ke, X.; Van Tendeloo, G.; Verpoort, F.
	Title	Tuning metal sites of DABCO MOF for gas purification at ambient conditions			Type	A1 Journal article
	Year	2015	Publication	Microporous and mesoporous materials: zeolites, clays, carbons and related materials	Abbreviated Journal	Micropor Mesopor Mat
	Volume	201	Issue	201	Pages	277-285
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Metalorganic frameworks (MOFs) have emerged as new porous materials for capture and separation of binary gas mixtures. Tuning the metal sites in MOF structures has an impact on properties, which enhance affinity of gas adsorption and selectivity (e.g., surface area, cavity, electric field, etc.). The synthesis and characterization of a M-DABCO series (M = Ni, Co, Cu, Zn) of MOFs are described in this study. The experiments were conducted using multicomponent gas mixtures and the Ideal Adsorbed Solution Theory (IAST) was applied to determine the CO2/CH4 selectivity. Experimental adsorption isotherms were fitted with a model equation to evaluate the characteristic adsorption energy (Isosteric, Qst) of this series. The Ni metal in the M-DABCO series reveals the best performance concerning CO2 adsorption and CH4/CO2 selectivity at ambient conditions based on IAST calculations. The combination of characterizations, calculations and adsorption experiments were used to discuss the metal impact on the adsorption sites in the M-DABCO series at ambient conditions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000345185200030	Publication Date	2014-09-20
	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	38	Open Access
	Notes	246791-Countatoms			Approved	Most recent IF: 3.615; 2015 IF: 3.453
	Call Number	c:irua:120473			Serial	3748
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	Author	Bittencourt, C.; Hecq, M.; Felten, A.; Pireaux, J.J.; Ghijsen, J.; Felicissimo, M.P.; Rudolf, P.; Drube, W.; Ke, X.; Van Tendeloo, G.
	Title	Platinumcarbon nanotube interaction			Type	A1 Journal article
	Year	2008	Publication	Chemical physics letters	Abbreviated Journal	Chem Phys Lett
	Volume	462	Issue	4/6	Pages	260-264
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The interaction between evaporated Pt and pristine or oxygen-plasma-treated multiwall carbon nanotubes (CNTs) is investigated. Pt is found to nucleate at defect sites, whether initially present or introduced by oxygen plasma treatment. The plasma treatment induces a uniform dispersion of Pt nanoparticles at the CNT surface. The absence of additional features in the C 1s core level spectrum indicates that no mixed PtC phase is formed. The formation of COPt bonds at the cluster-CNT interface is suggested to reduce the electronic interaction between Pt nanoparticles and the CNT surface.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000258830900025	Publication Date	2008-07-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0009-2614;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.815	Times cited	62	Open Access
	Notes	Pai			Approved	Most recent IF: 1.815; 2008 IF: 2.169
	Call Number	UA @ lucian @ c:irua:76489			Serial	2652
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	Author	Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Ghijsen, J.; Ewels, C.P.
	Title	Study of the interaction between copper and carbon nanotubes			Type	A1 Journal article
	Year	2012	Publication	Chemical physics letters	Abbreviated Journal	Chem Phys Lett
	Volume	535	Issue		Pages	80-83
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Copper deposited by thermal evaporation onto pristine and oxygen plasma treated carbon nanotubes (CNTs) diffuse over the CNT surface, coalescing and forming crystalline islands. The nucleation sites of the islands are preferentially defects, and more homogeneous island dispersion was observed at the CNT oxygen functionalized surface. The presence of weakly bound oxygen atoms at the CNT surface induces the formation of CuO bonds at the Cu/CNT interface, as described through density functional calculations. Exposure to air allows further oxidation to facetted crystalline Cu2O. Oxygen plasma pre-treatment represents a promising route for homogenous disperse Cu2O nanoparticle decoration of CNTs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000303437900015	Publication Date	2012-03-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0009-2614;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.815	Times cited	27	Open Access
	Notes				Approved	Most recent IF: 1.815; 2012 IF: 2.145
	Call Number	UA @ lucian @ c:irua:97704			Serial	3336
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	Author	Adjizian, J.J.; De Marco, P.; Suarez-Martinez, I.; El Mel, A.A.; Snyders, R.; Gengler, R.Y.N.; Rudolf, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Ewels, C.P.;
	Title	Platinum and palladium on carbon nanotubes : experimental and theoretical studies			Type	A1 Journal article
	Year	2013	Publication	Chemical physics letters	Abbreviated Journal	Chem Phys Lett
	Volume	571	Issue		Pages	44-48
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Pristine and oxygen plasma functionalised carbon nanotubes (CNTs) were studied after the evaporation of Pt and Pd atoms. High resolution transmission electron microscopy shows the formation of metal nanoparticles at the CNT surface. Oxygen functional groups grafted by the plasma functionalization act as nucleation sites for metal nanoparticles. Analysis of the C1s core level spectra reveals that there is no covalent bonding between the Pt or Pd atoms and the CNT surface. Unlike other transition metals such as titanium and copper, neither Pd nor Pt show strong oxygen interaction or surface oxygen scavenging behaviour.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000319109900007	Publication Date	2013-04-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0009-2614;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.815	Times cited	23	Open Access
	Notes	Countatoms; Cost			Approved	Most recent IF: 1.815; 2013 IF: 1.991
	Call Number	UA @ lucian @ c:irua:108706			Serial	2650
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	Author	Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Tagmatarchis, N.; Guttmann, P.
	Title	NEXAFS spectromicroscopy of suspended carbon nanohorns			Type	A1 Journal article
	Year	2013	Publication	Chemical physics letters	Abbreviated Journal	Chem Phys Lett
	Volume	587	Issue		Pages	85-87
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We demonstrate that near-edge X-ray-absorption fine-structure spectroscopy combined with full-field transmission X-ray microscopy can be used to study the electronic structure of suspended carbon nanohorns. Based on reports of electronic structure calculations additional spectral features observed in the π region of the NEXAFS spectrum recorded on the carbon nanohorns were associated to the presence of the pentagonal rings and the folding of the graphene sheet.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000326104500016	Publication Date	2013-09-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0009-2614;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.815	Times cited	4	Open Access
	Notes	Fp7; Countatoms;			Approved	Most recent IF: 1.815; 2013 IF: 1.991
	Call Number	UA @ lucian @ c:irua:111592			Serial	2339
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	Author	Guttmann, P.; Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Umek, P.; Arcon, D.; Ewels, C.P.; Rehbein, S.; Heim, S.; Schneider, G.
	Title	TXM-NEXAFS of TiO₂-based nanostructures			Type	P1 Proceeding
	Year	2011	Publication	AIP conference proceedings	Abbreviated Journal
	Volume	1365	Issue		Pages	437-440
	Keywords	P1 Proceeding; Electron microscopy for materials research (EMAT)
	Abstract	In this work, electronic properties of individual TiOx-pristine nanoribbons (NR) prepared by hydrothermal treatment of anatase TiO(2) micro-particles were studied using the HZB transmission x-ray microscope (TXM) at the BESSY II undulator beamline U41-FSGM. NEXAFS is ideally suited to study TiO(2)-based materials because both the O K-edge and Ti L-edge features are very sensitive to the local bonding environment, providing diagnostic information about the crystal structures and oxidation states of various forms of titanium oxides and sub-oxides. TXM-NEXAFS combines full-field x-ray microscopy with spectroscopy, allowing the study of the electronic structure of individual nanostructures with spatial resolution better than 25 nm and a spectral resolution of up to E/Delta E = 10000. The typical image field in TXM-NEXAFS measurements is about 10 mu m. 10 mu m, which is large compared to the individual nanoparticle. Therefore, one image stack already contains statistically significant data. In addition, the directional electric field vector ((E) over bar) of the x-rays can be used as a “search tool” for the direction of chemical bonds of the atom selected by its absorption edge.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York	Editor
	Language		Wos	000298672400103	Publication Date	2011-09-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	2	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:113071			Serial	3789
Permanent link to this record