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	Author	Skaltsas, T.; Ke, X.; Bittencourt, C.; Tagmatarchis, N.
	Title	Ultrasonication induces oxygenated species and defects onto exfoliated graphene			Type	A1 Journal article
	Year	2013	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	117	Issue	44	Pages	23272-23278
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The effect of ultrasonication parameters, such as time and power applied, to exfoliate graphite in o-dichlorobenzene (o-DCB) and N-methyl-1,2-pyrrolidone (NMP) was examined. It was found that the concentration of graphene was higher in o-DCB, while its dispersibility was increased when sonication was applied for a longer period and/or at higher power. However, spectroscopic examination by X-ray photoelectron spectroscopy (XPS) revealed that ultrasonication causes defects and induces oxygen functional groups in the form of carboxylic acids and ethers/epoxides onto the graphene lattice. Additional proof for the latter arose from Raman, IR, and thermogravimetry studies. The carboxylic acids and ethers/epoxides onto exfoliated graphene were derived from air during ultrasonication and found independent of the solvent used for the exfoliation and the power and/or time ultrasonication applied. Quantitative evaluation of the amount of oxygenated species present on exfoliated graphene as performed by high-resolution XPS revealed that the relative oxygen percentage was higher when exfoliation was performed in NMP. Finally, the sonication time and/or power affected the oxygen content on exfoliated graphene, since extended ultrasonication resulted in a decrease in the oxygen content on exfoliated graphene, with a simultaneous increase of defected sp(3) carbon atoms.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000326845400090	Publication Date	2013-10-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447;1932-7455;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	65	Open Access
	Notes				Approved	Most recent IF: 4.536; 2013 IF: 4.835
	Call Number	UA @ lucian @ c:irua:112710			Serial	3797
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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	Pietra, F.; van Dijk-Moes, R.J.A.; Ke, X.; Bals, S.; Van Tendeloo, G.; de Mello Donega, C.; Vanmaekelbergh, D.
	Title	Synthesis of highly luminescent silica-coated CdSe/CdS nanorods			Type	A1 Journal article
	Year	2013	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	25	Issue	17	Pages	3427-3434
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	CdSe(core)/CdS(shell) nanorods (NRs) have been extensively investigated for their unique optical properties, such as high photoluminescence (PL) quantum efficiency (QE) and polarized light emission. The incorporation of these NRs in silica (SiO2) is of high interest, since this renders them processable in polar solvents while increasing their photochemical stability, which would be beneficial for their application in LEDs and as biolabels. We report the synthesis of highly luminescent silica-coated CdSe/CdS NRs, by using the reverse micelle method. The mechanism for the encapsulation of the NRs in silica is unravelled and shown to be strongly influenced by the NR shape and its asymmetry. This is attributed to both the different morphology and the different crystallographic nature of the facets terminating the opposite tips of the NRs. These results lead to the formation of a novel class of NR architectures, whose symmetry can be controlled by tuning the degree of coverage of the silica shell. Interestingly, the encapsulation of the NRs in silica leads to a remarkable increase in their photostability, while preserving their optical properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000330097900004	Publication Date	2013-08-13
	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	46	Open Access
	Notes	262348 ESMI; 246791 COUNTATOMS; Hercules			Approved	Most recent IF: 9.466; 2013 IF: 8.535
	Call Number	UA @ lucian @ c:irua:110037			Serial	3456
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	Author	Groeneveld, E.; Witteman, L.; Lefferts, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; de Mello Donega, C.
	Title	Tailoring ZnSe-CdSe colloidal quantum dots via cation exchange : from core/shell to alloy nanocrystals			Type	A1 Journal article
	Year	2013	Publication	ACS nano	Abbreviated Journal	Acs Nano
	Volume	7	Issue	9	Pages	7913-7930
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	We report a study of Zn2+ by Cd2+ cation exchange (CE) in colloidal ZnSe nanocrystals (NCs). Our results reveal that CE in ZnSe NCs is a thermally activated isotropic process. The CE efficiency (i.e., fraction of Cd2+ ions originally in solution, Cdsol, that is incorporated in the ZnSe NC) increases with temperature and depends also on the Cdsol/ZnSe ratio. Interestingly, the reaction temperature can be used as a sensitive parameter to tailor both the composition and the elemental distribution profile of the product (Zn,Cd)Se NCs. At 150 °C ZnSe/CdSe core/shell hetero-NCs (HNCs) are obtained, while higher temperatures (200 and 220 °C) produce (Zn1xCdx)Se gradient alloy NCs, with increasingly smoother gradients as the temperature increases, until homogeneous alloy NCs are obtained at T ≥ 240 °C. Remarkably, sequential heating (150 °C followed by 220 °C) leads to ZnSe/CdSe core/shell HNCs with thicker shells, rather than (Zn1xCdx)Se gradient alloy NCs. Thermal treatment at 250 °C converts the ZnSe/CdSe core/shell HNCs into (Zn1xCdx)Se homogeneous alloy NCs, while preserving the NC shape. A mechanism for the cation exchange in ZnSe NCs is proposed, in which fast CE takes place at the NC surface, and is followed by relatively slower thermally activated solid-state cation diffusion, which is mediated by Frenkel defects. The findings presented here demonstrate that cation exchange in colloidal ZnSe NCs provides a very sensitive tool to tailor the nature and localization regime of the electron and hole wave functions and the optoelectronic properties of colloidal ZnSeCdSe NCs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000330016900051	Publication Date	2013-08-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1936-0851;1936-086X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	13.942	Times cited	153	Open Access
	Notes	262348 Esmi; 246791 Countatoms			Approved	Most recent IF: 13.942; 2013 IF: 12.033
	Call Number	UA @ lucian @ c:irua:110038			Serial	3469
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	Author	Ke, X.; Turner, S.; Quintana, M.; Hadad, C.; Montellano-López, A.; Carraro, M.; Sartorel, A.; Bonchio, M.; Prato, M.; Bittencourt, C.; Van Tendeloo, G.;
	Title	Dynamic motion of Ru-polyoxometalate ions (POMs) on functionalized few-layer graphene			Type	A1 Journal article
	Year	2013	Publication	Small	Abbreviated Journal	Small
	Volume	9	Issue	23	Pages	3922-3927
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The interaction and stability of Ru4POM on few layer graphene via functional groups is investigated by time-dependent imaging using aberration-corrected transmission electron microscopy. The Ru4POM demonstrates dynamic motion on the graphene surface with its frequency and amplitude of rotation related to the nature of the functional group used. The stability of the Ru4POMgraphene hybrid corroborates its long-term robustness when applied to multielectronic catalytic processes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000331282400003	Publication Date	2013-07-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1613-6810;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.643	Times cited	16	Open Access
	Notes	IAP-7; Countatoms;			Approved	Most recent IF: 8.643; 2013 IF: 7.514
	Call Number	UA @ lucian @ c:irua:115768			Serial	763
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	Author	Tsoufis, T.; Georgakilas, V.; Ke, X.; Van Tendeloo, G.; Rudolf, P.; Gournis, D.
	Title	Incorporation of pure fullerene into organoclays : towards C₆₀-pillared clay structures			Type	A1 Journal article
	Year	2013	Publication	Chemistry: a European journal	Abbreviated Journal	Chem-Eur J
	Volume	19	Issue	24	Pages	7937-7943
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In this work, we demonstrate the successful incorporation of pure fullerene from solution into two-dimensional layered aluminosilicate minerals. Pure fullerenes are insoluble in water and neutral in terms of charge, hence they cannot be introduced into the clay galleries by ion exchange or intercalation from water solution. To overcome this bottleneck, we organically modified the clay with quaternary amines by using well-established reactions in clay science in order to expand the interlayer space and render the galleries organophilic. During the reaction with the fullerene solution, the organic solvent could enter into the clay galleries, thus transferring along the fullerene molecules. Furthermore, we demonstrate that the surfactant molecules, can be selectively removed by either simple ion-exchange reaction (e.g., interaction with Al(NO3)3 solution to replace the surfactant molecules with Al3+ ions) or thermal treatment (heating at 350 °C) to obtain novel fullerene-pillared clay structures exhibiting enhanced surface area. The synthesized hybrid materials were characterized in detail by a combination of experimental techniques including powder X-ray diffraction, transmission electron microscopy, X-ray photoemission, and UV/Vis spectroscopy as well as thermal analysis and nitrogen adsorptiondesorption measurements. The reported fullerene-pillared clay structures constitute a new hybrid system with very promising potential for the use in areas such as gas storage and/or gas separation due to their high surface area.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000319825500035	Publication Date	2013-04-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0947-6539;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.317	Times cited	3	Open Access
	Notes	262348 Esmi; 246791 Countatoms			Approved	Most recent IF: 5.317; 2013 IF: 5.696
	Call Number	UA @ lucian @ c:irua:107347			Serial	1599
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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	Vereecke, B.; van der Veen, M.H.; Sugiura, M.; Kashiwagi, Y.; Ke, X.; Cott, D.J.; Hantschel, T.; Huyghebaert, C.; Tökei, Z.
	Title	Wafer-level electrical evaluation of vertical carbon nanotube bundles as a function of growth temperature			Type	A1 Journal article
	Year	2013	Publication	Japanese journal of applied physics	Abbreviated Journal	Jpn J Appl Phys
	Volume	52	Issue	42	Pages	04cn02-5
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We have evaluated the resistance of carbon nanotubes (CNTs) grown at a CMOS-compatible temperature using a realistic integration scheme. The structural analysis of the CNTs by transmission electron microscopy (TEM) showed that the degree of graphitization decreased significantly when the growth temperature was decreased from 540 to 400 °C. The CNTs were integrated to form 150-nm-diameter vertical interconnects between a TiN layer and Cu metal trenches on 200 mm full wafers. Wafers with CNTs grown at low temperature were found to have a lower single-contact resistance than those produced at high temperatures. Thickness measurements showed that the low contact resistance is a result of small contact height. This height dependence is masking the impact of CNT graphitization quality on resistance. When benchmarking our results with data from the literature, a relationship between resistivity and growth temperature cannot be found for CNT-based vertical interconnects.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Kyoto	Editor
	Language		Wos	000320002400150	Publication Date	2013-03-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-4922;1347-4065;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.384	Times cited	5	Open Access
	Notes				Approved	Most recent IF: 1.384; 2013 IF: 1.057
	Call Number	UA @ lucian @ c:irua:108713			Serial	3902
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	Author	Ke, X.; Bittencourt, C.; Bals, S.; Van Tendeloo, G.
	Title	Low-dose patterning of platinum nanoclusters on carbon nanotubes by focused-electron-beam-induced deposition as studied by TEM			Type	A1 Journal article
	Year	2013	Publication	Beilstein journal of nanotechnology	Abbreviated Journal	Beilstein J Nanotech
	Volume	4	Issue		Pages	77-86
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Focused-electron-beam-induced deposition (FEBID) is used as a direct-write approach to decorate ultrasmall Pt nanoclusters on carbon nanotubes at selected sites in a straightforward maskless manner. The as-deposited nanostructures are studied by transmission electron microscopy (TEM) in 2D and 3D, demonstrating that the Pt nanoclusters are well-dispersed, covering the selected areas of the CNT surface completely. The ability of FEBID to graft nanoclusters on multiple sides, through an electron-transparent target within one step, is unique as a physical deposition method. Using high-resolution TEM we have shown that the CNT structure can be well preserved thanks to the low dose used in FEBID. By tuning the electron-beam parameters, the density and distribution of the nanoclusters can be controlled. The purity of as-deposited nanoclusters can be improved by low-energy electron irradiation at room temperature.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000314499700001	Publication Date	2013-02-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2190-4286;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.127	Times cited	12	Open Access
	Notes	262348 ESMI; 246791 COUNTATOMS; FWO G002410N; ESF Cost Action NanoTP MP0901			Approved	Most recent IF: 3.127; 2013 IF: 2.332
	Call Number	UA @ lucian @ c:irua:106187			Serial	1848
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	Author	Quintana, M.; López, A.M.; Rapino, S.; Toma, F.M.; Iurlo, M.; Carraro, M.; Sartorel, A.; Maccato, C.; Ke, X.; Bittencourt, C.; Da Ros, T.; Van Tendeloo, G.; Marcaccio, M.; Paolucci, F.; Prato, M.; Bonchio, M.;
	Title	Knitting the catalytic pattern of artificial photosynthesis to a hybrid graphene nanotexture			Type	A1 Journal article
	Year	2013	Publication	ACS nano	Abbreviated Journal	Acs Nano
	Volume	7	Issue	1	Pages	811-817
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The artificial leaf project calls for new materials enabling multielectron catalysis with minimal overpotential, high turnover frequency, and long-term stability. Is graphene a better material than carbon nanotubes to enhance water oxidation catalysis for energy applications? Here we show that functionalized graphene with a tailored distribution of polycationic, quaternized, ammonium pendants provides an sp(2) carbon nanoplatform to anchor a totally inorganic tetraruthenate catalyst, mimicking the oxygen evolving center of natural PSII. The resulting hybrid material displays oxygen evolution at overpotential as low as 300 mV at neutral pH with negligible loss of performance after 4 h testing. This multilayer electroactive asset enhances the turnover frequency by 1 order of magnitude with respect to the isolated catalyst, and provides a definite up-grade of the carbon nanotube material, with a similar surface functionalization. Our innovation is based on a noninvasive, synthetic protocol for graphene functionalization that goes beyond the ill-defined oxidation-reduction methods, allowing a definite control of the surface properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000314082800088	Publication Date	2012-12-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1936-0851;1936-086X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	13.942	Times cited	69	Open Access
	Notes	246791 COUNTATOMS; 262348 ESMI; ESF Cost Action NanoTP MP0901			Approved	Most recent IF: 13.942; 2013 IF: 12.033
	Call Number	UA @ lucian @ c:irua:107707			Serial	1766
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	Author	Bittencourt, C.; Krüger, P.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Ewels, C.; Umek, P.; Guttmann, P.
	Title	Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations			Type	A1 Journal article
	Year	2012	Publication	Beilstein journal of nanotechnology	Abbreviated Journal	Beilstein J Nanotech
	Volume	3	Issue		Pages	789-797
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Recent advances in near-edge X-ray-absorption fine-structure spectroscopy coupled with transmission X-ray microscopy (NEXAFS-TXM) allow large-area mapping investigations of individual nano-objects with spectral resolution up to E/Delta E = 104 and spatial resolution approaching 10 nm. While the state-of-the-art spatial resolution of X-ray microscopy is limited by nanostructuring process constrains of the objective zone plate, we show here that it is possible to overcome this through close coupling with high-level theoretical modelling. Taking the example of isolated bundles of hydrothermally prepared sodium titanate nanotubes ((Na,H)TiNTs) we are able to unravel the complex nanoscale structure from the NEXAFS-TXM data using multichannel multiple-scattering calculations, to the extent of being able to associate specific spectral features in the O K-edge and Ti L-edge with oxygen atoms in distinct sites within the lattice. These can even be distinguished from the contribution of different hydroxyl groups to the electronic structure of the (Na,H)TiNTs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000311482400001	Publication Date	2012-11-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2190-4286;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.127	Times cited	13	Open Access
	Notes				Approved	Most recent IF: 3.127; 2012 IF: 2.374
	Call Number	UA @ lucian @ c:irua:105140			Serial	3684
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	Author	Schulze, A.; Hantschel, T.; Dathe, A.; Eyben, P.; Ke, X.; Vandervorst, W.
	Title	Electrical tomography using atomic force microscopy and its application towards carbon nanotube-based interconnects			Type	A1 Journal article
	Year	2012	Publication	Nanotechnology	Abbreviated Journal	Nanotechnology
	Volume	23	Issue	30	Pages	305707
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The fabrication and integration of low-resistance carbon nanotubes (CNTs) for interconnects in future integrated circuits requires characterization techniques providing structural and electrical information at the nanometer scale. In this paper we present a slice-and-view approach based on electrical atomic force microscopy. Material removal achieved by successive scanning using doped ultra-sharp full-diamond probes, manufactured in-house, enables us to acquire two-dimensional (2D) resistance maps originating from different depths (equivalently different CNT lengths) on CNT-based interconnects. Stacking and interpolating these 2D resistance maps results in a three-dimensional (3D) representation (tomogram). This allows insight from a structural (e.g. size, density, distribution, straightness) and electrical point of view simultaneously. By extracting the resistance evolution over the length of an individual CNT we derive quantitative information about the resistivity and the contact resistance between the CNT and bottom electrode.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000306333500029	Publication Date	2012-07-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0957-4484;1361-6528;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.44	Times cited	29	Open Access
	Notes				Approved	Most recent IF: 3.44; 2012 IF: 3.842
	Call Number	UA @ lucian @ c:irua:100750			Serial	895
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	Author	Gengler, R.Y.N.; Toma, L.M.; Pardo, E.; Lloret, F.; Ke, X.; Van Tendeloo, G.; Gournis, D.; Rudolf, P.
	Title	Prussian blue analogues of reduced dimensionality			Type	A1 Journal article
	Year	2012	Publication	Small	Abbreviated Journal	Small
	Volume	8	Issue	16	Pages	2532-2540
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Mixed-valence polycyanides (Prussian Blue analogues) possess a rich palette of properties spanning from room-temperature ferromagnetism to zero thermal expansion, which can be tuned by chemical modifications or the application of external stimuli (temperature, pressure, light irradiation). While molecule-based materials can combine physical and chemical properties associated with molecular-scale building blocks, their successful integration into real devices depends primarily on higher-order properties such as crystal size, shape, morphology, and organization. Herein a study of a new reduced-dimensionality system based on Prussian Blue analogues (PBAs) is presented. The system is built up by means of a modified Langmuir-Blodgett technique, where the PBA is synthesized from precursors in a self-limited reaction on a clay mineral surface. The focus of this work is understanding the magnetic properties of the PBAs in different periodic, low-dimensional arrangements, and the influence of the “on surface” synthesis on the final properties and dimensionality of the system.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000307390300012	Publication Date	2012-07-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1613-6810;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.643	Times cited	17	Open Access
	Notes				Approved	Most recent IF: 8.643; 2012 IF: 7.823
	Call Number	UA @ lucian @ c:irua:101104			Serial	2736
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	Author	Bertoni, G.; Grillo, V.; Brescia, R.; Ke, X.; Bals, S.; Catellani, A.; Li, H.; Manna, L.
	Title	Direct determination of polarity, faceting, and core location in colloidal core/shell wurtzite semiconductor nanocrystals			Type	A1 Journal article
	Year	2012	Publication	ACS nano	Abbreviated Journal	Acs Nano
	Volume	6	Issue	7	Pages	6453-6461
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The ability to determine the atomic arrangement and termination of various facets of surfactant-coated nanocrystals is of great importance for understanding their growth mechanism and their surface properties and represents a critical piece of information that can be coupled to other experimental techniques and to calculations. This is especially appealing in the study of nanocrystals that can be grown in strongly anisotropic shapes, for which the relative growth rates of various facets can be influenced under varying reaction conditions. Here we show that in two representative cases of rod-shaped nanocrystals in the wurtzite phase (CdSe(core)/CdS(shell) and ZnSe(core)/ZnS(shell) nanorods) the terminations of the polar facets can be resolved unambiguously by combining advanced electron microscopy techniques, such as aberration-corrected HRTEM with exit wave reconstruction or aberration-corrected HAADF-STEM. The [0001] and [000-1] polar directions of these rods, which grow preferentially along their c-axis, are revealed clearly, with one side consisting of the Cd (or Zn)-terminated (0001) facet and the other side with a pronounced faceting due to Cd (or Zn)-terminated {10-1-1} facets. The lateral faceting of the rods is instead dominated by three nonpolar {10-10} facets. The core buried in the nanostructure can be localized in both the exit wave phase and HAADF-STEM images.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000306673800079	Publication Date	2012-06-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1936-0851;1936-086X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	13.942	Times cited	63	Open Access
	Notes	The authors gratefully acknowledge funding from the European Research Council under grant number 240111 (NANO-ARCH) and the financial support from the Flemish Hercules 3 Programme for large infrastructures. G.B. and V.G. thank E. Rotunno for his help with STEM_CELL and IWFR.			Approved	Most recent IF: 13.942; 2012 IF: 12.062
	Call Number	UA @ lucian @ c:irua:101138			Serial	710
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	Author	Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.;
	Title	Gold clusters on WO₃ nanoneedles grown via AACVD : XPS and TEM studies			Type	A1 Journal article
	Year	2012	Publication	Materials chemistry and physics	Abbreviated Journal	Mater Chem Phys
	Volume	134	Issue	2/3	Pages	809-813
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lausanne	Editor
	Language		Wos	000305918200038	Publication Date	2012-04-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0254-0584;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.084	Times cited	52	Open Access
	Notes	Iap			Approved	Most recent IF: 2.084; 2012 IF: 2.072
	Call Number	UA @ lucian @ c:irua:97705			Serial	1356
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	Author	Bittencourt, C.; Hitchock, A.P.; Ke, X.; Van Tendeloo, G.; Ewels, C.P.; Guttmann, P.
	Title	X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge			Type	A1 Journal article
	Year	2012	Publication	Beilstein journal of nanotechnology	Abbreviated Journal	Beilstein J Nanotech
	Volume	3	Issue		Pages	345-350
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	We demonstrate that near-edge X-ray-absorption fine-structure spectra combined with full-field transmission X-ray microscopy can be used to study the electronic structure of graphite flakes consisting of a few graphene layers. The flake was produced by exfoliation using sodium cholate and then isolated by means of density-gradient ultracentrifugation. An image sequence around the carbon K-edge, analyzed by using reference spectra for the in-plane and out-of-plane regions of the sample, is used to map and spectrally characterize the flat and folded regions of the flake. Additional spectral features in both π and σ regions are observed, which may be related to the presence of topological defects. Doping by metal impurities that were present in the original exfoliated graphite is indicated by the presence of a pre-edge signal at 284.2 eV.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000303243400001	Publication Date	2012-04-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2190-4286;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.127	Times cited	15	Open Access
	Notes				Approved	Most recent IF: 3.127; 2012 IF: 2.374
	Call Number	UA @ lucian @ c:irua:97703			Serial	3924
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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	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	He, Z.; Ke, X.; Bals, S.; Van Tendeloo, G.
	Title	Direct evidence for the existence of multi-walled carbon nanotubes with hexagonal cross-sections			Type	A1 Journal article
	Year	2012	Publication	Carbon	Abbreviated Journal	Carbon
	Volume	50	Issue	7	Pages	2524-2529
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Carbon nanotubes (CNTs) with a polygonal cross-section have been paid increasing attention since their three-dimensional structure is related to specific physical properties, which are found to be different in comparison to CNTs with a circular cross-section. Here, we report the existence of novel multi-walled CNTs yielding walls with a rounded-hexagonal configuration. This structure was directly confirmed for the first time by both cross-sectional transmission electron microscopy and electron tomography. The morphology of the Fe catalytic particle also exhibits hexagonal characteristics, and is proposed as the origin of the formation of the rounded-hexagonal walls of the CNT. This observation is of great importance with respect to the design of polygonal (such as pentagonal or hexagonal) cross-sectional CNTs. By controlling the morphology of the catalytic nanoparticles it will be possible to grow CNTs with desired electronic and mechanical properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000303038400015	Publication Date	2012-02-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0008-6223;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.337	Times cited	8	Open Access
	Notes	Fwo			Approved	Most recent IF: 6.337; 2012 IF: 5.868
	Call Number	UA @ lucian @ c:irua:96956			Serial	711
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	Author	Ustarroz, J.; Ke, X.; Hubin, A.; Bals, S.; Terryn, H.
	Title	New insights into the early stages of nanoparticle electrodeposition			Type	A1 Journal article
	Year	2012	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	116	Issue	3	Pages	2322-2329
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Electrodeposition is an increasingly important method to synthesize supported nanoparticles, yet the early stages of electrochemical nanoparticle formation are not perfectly understood. In this paper, the early stages of silver nanoparticle electrodeposition on carbon substrates have been studied by aberration-corrected TEM, using carbon-coated TEM grids as electrochemical electrodes. In this manner we have access to as-deposited nanoparticle size distribution and structural characterization at the atomic scale combined with electrochemical measurements, which represents a breakthrough in a full understanding of the nanoparticle electrodeposition mechanisms. Whereas classical models, based upon characterization at the nanoscale, assume that electrochemical growth is only driven by direct attachment, the results reported hereafter indicate that early nanoparticle growth is mostly driven by nanocluster surface movement and aggregation. Hence, we conclude that electrochemical nulceation and growth models should be revised and that an electrochemical aggregative growth mechanism should be considered in the early stages of nanoparticle electrodeposition.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000299584400037	Publication Date	2011-12-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447;1932-7455;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	104	Open Access
	Notes	Fwo			Approved	Most recent IF: 4.536; 2012 IF: 4.814
	Call Number	UA @ lucian @ c:irua:96225			Serial	2316
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	Author	Guttmann, P.; Bittencourt, C.; Rehbein, S.; Umek, P.; Ke, X.; Van Tendeloo, G.; Ewels, C.P.; Schneider, G.
	Title	Nanoscale spectroscopy with polarized X-rays by NEXAFS-TXM			Type	A1 Journal article
	Year	2012	Publication	Nature photonics	Abbreviated Journal	Nat Photonics
	Volume	6	Issue	1	Pages	25-29
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Near-edge X-ray absorption spectroscopy (NEXAFS)1 is an essential analytical tool in material science. Combining NEXAFS with scanning transmission X-ray microscopy (STXM) adds spatial resolution and the possibility to study individual nanostructures2, 3. Here, we describe a full-field transmission X-ray microscope (TXM) that generates high-resolution, large-area NEXAFS data with a collection rate two orders of magnitude faster than is possible with STXM. The TXM optical design combines a spectral resolution of E/ΔE = 1 × 104 with a spatial resolution of 25 nm in a field of view of 1520 µm and a data acquisition time of ~1 s. As an example, we present image stacks and polarization-dependent NEXAFS spectra from individual anisotropic sodium and protonated titanate nanoribbons. Our NEXAFS-TXM technique has the advantage that one image stack visualizes a large number of nanostructures and therefore already contains statistical information. This new high-resolution NEXAFS-TXM technique opens the way to advanced nanoscale science studies.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000298416200011	Publication Date	2011-11-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1749-4885;1749-4893;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	37.852	Times cited	76	Open Access
	Notes				Approved	Most recent IF: 37.852; 2012 IF: 27.254
	Call Number	UA @ lucian @ c:irua:94198			Serial	2272
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	Author	Corthals, S.; van Noyen, J.; Geboers, J.; Vosch, T.; Liang, D.; Ke, X.; Hofkens, J.; Van Tendeloo, G.; Jacobs, P.; Sels, B.
	Title	The beneficial effect of CO₂ in the low temperature synthesis of high quality carbon nanofibers and thin multiwalled carbon nanotubes from CH_{_{4}} over Ni catalysts			Type	A1 Journal article
	Year	2012	Publication	Carbon	Abbreviated Journal	Carbon
	Volume	50	Issue	2	Pages	372-384
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A low temperature chemical vapor deposition method is described for converting CH4 into high-quality carbon nanofibers (CNFs) using a Ni catalyst supported on either spinel or perovskite oxides in the presence of CO2. The addition of CO2 has a significant influence on CNF purity and stability, while the CNF diameter distribution is significantly narrowed. Ultimately, the addition of CO2 changes the CNF structure from fishbone fibers to thin multiwalled carbon nanotubes. A new in situ cooling principle taking into account dry reforming chemistry and thermodynamics is introduced to account for the structural effects of CO2.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000297397700004	Publication Date	2011-09-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0008-6223;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.337	Times cited	26	Open Access
	Notes	Iwt; Iap			Approved	Most recent IF: 6.337; 2012 IF: 5.868
	Call Number	UA @ lucian @ c:irua:93626			Serial	228
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	Author	Bittencourt, C.; Navio, C.; Nicolay, A.; Ruelle, B.; Godfroid, T.; Snyders, R.; Colomer, J.-F.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Suarez-Martinez, I.; Ewels, C.P.
	Title	Atomic oxygen functionalization of vertically aligned carbon nanotubes			Type	A1 Journal article
	Year	2011	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	115	Issue	42	Pages	20412-20418
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Vertically aligned multiwalled carbon nanotubes (v-MWCNTs) are functionalized using atomic oxygen generated in a microwave plasma. X-ray photoelectron spectroscopy depth profile analysis shows that the plasma treatment effectively grafts oxygen exclusively at the v-MWCNT tips. Electron microscopy shows that neither the vertical alignment nor the structure of v-MWCNTs were affected by the plasma treatment. Density functional calculations suggest assignment of XPS C 1s peaks at 286.6 and 287.5 eV, to epoxy and carbonyl functional groups, respectively.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000296205600009	Publication Date	2011-10-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447;1932-7455;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	31	Open Access
	Notes	Iap			Approved	Most recent IF: 4.536; 2011 IF: 4.805
	Call Number	UA @ lucian @ c:irua:91890			Serial	174
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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	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
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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	Quintana, M.; Ke, X.; Van Tendeloo, G.; Meneghetti, M.; Bittencourt, C.; Prato, M.
	Title	Light-induced selective deposition of Au nanoparticles on single-wall carbon nanotubes			Type	A1 Journal article
	Year	2010	Publication	ACS nano	Abbreviated Journal	Acs Nano
	Volume	4	Issue	10	Pages	6105-6113
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Novel applications of single-walled carbon nanotubes (SWNT) rely on the development of new strategies to make them easier to handle without affecting their structural properties. In this work, we have selectively deposited Au nanoparticles (Au NP) on SWNT assisted by UV light irradiation. XPS analysis and UV-vis spectroscopy indicate that the deposition occurs at the defects generated after oxidation of the SWNT. By addition of n-dodecylthiol, the separation of oxidized tubes with Au NP (Au-ox-SWNT) from tubes devoid of Au NP (bare tubes, b-SWNT) was achieved. Raman and UV-vis-NIR spectra indicate that UV irradiation induces a faster nucleation of Au NP on metallic SWNT. This new technique can be useful for the preparation of nanohybrid composites with enhanced properties, as increased thermal stability, and to obtain purified SWNT.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000283453700081	Publication Date	2010-09-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1936-0851;1936-086X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	13.942	Times cited	26	Open Access
	Notes				Approved	Most recent IF: 13.942; 2010 IF: 9.865
	Call Number	UA @ lucian @ c:irua:99202			Serial	1819
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	Author	Felten, A.; Gillon, X.; Gulas, M.; Pireaux, J.-J.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Najafi, E.; Hitchcock, A.P.
	Title	Measuring point defect density in individual carbon nanotubes using polarization-dependent X-ray microscopy			Type	A1 Journal article
	Year	2010	Publication	ACS nano	Abbreviated Journal	Acs Nano
	Volume	4	Issue	8	Pages	4431-4436
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The presence of defects in carbon nanotubes strongly modifies their electrical, mechanical, and chemical properties. It was long thought undesirable, but recent experiments have shown that introduction of structural defects using ion or electron irradiation can lead to novel nanodevices. We demonstrate a method for detecting and quantifying point defect density in individual carbon nanotubes (CNTs) based on measuring the polarization dependence (linear dichroism) of the C 1s → π* transition at specific locations along individual CNTs with a scanning transmission X-ray microscope (STXM). We show that STXM can be used to probe defect density in individual CNTs with high spatial resolution. The quantitative relationship between ion dose, nanotube diameter, and defect density was explored by purposely irradiating selected sections of nanotubes with kiloelectronvolt (keV) Ga+ ions. Our results establish polarization-dependent X-ray microscopy as a new and very powerful characterization technique for carbon nanotubes and other anisotropic nanostructures.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000281052700014	Publication Date	2010-07-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1936-0851;1936-086X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	13.942	Times cited	26	Open Access
	Notes				Approved	Most recent IF: 13.942; 2010 IF: 9.865
	Call Number	UA @ lucian @ c:irua:84734			Serial	1966
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	Author	Goffin, A.-L.; Duquesne, E.; Raquez, J.-M.; Miltner, H.E.; Ke, X.; Alexandre, M.; Van Tendeloo, G.; van Mele, B.; Dubois, P.
	Title	From polyester grafting onto POSS nanocage by ring-opening polymerization to high performance polyester/POSS nanocomposites			Type	A1 Journal article
	Year	2010	Publication	Journal of materials chemistry	Abbreviated Journal	J Mater Chem
	Volume	20	Issue	42	Pages	9415-9422
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Polyester-grafted polyhedral oligomeric silsesquioxane (POSS) nanohybrids selectively produced by ring-opening polymerization of ε-caprolactone and L,L-lactide (A.-L. Goffin, E. Duquesne, S. Moins, M. Alexandre, Ph. Dubois, Eur. Polym. Journal, 2007, 43, 4103) were studied as masterbatches by melt-blending within their corresponding commercial polymeric matrices, i.e., poly(ε-caprolactone) (PCL) and poly(L,L-lactide) (PLA). For the sake of comparison, neat POSS nanoparticles were also dispersed in PCL and PLA. The objective was to prepare aliphatic polyester-based nanocomposites with enhanced crystallization behavior, and therefore, enhanced thermo-mechanical properties. Wide-angle X-ray scattering and transmission electron microscopy attested for the dispersion of individualized POSS nanoparticles in the resulting nanocomposite materials only when the polyester-grafted POSS nanohybrid was used as a masterbatch. The large impact of such finely dispersed (grafted) nanoparticles on the crystallization behavior for the corresponding polyester matrices was noticed, as evidenced by differential scanning calorimetry analysis. Indeed, well-dispersed POSS nanoparticles acted as efficient nucleating sites, significantly increasing the crystallinity degree of both PCL and PLA matrices. As a result, a positive impact on thermo-mechanical properties was highlighted by dynamic mechanical thermal analysis.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000283264500017	Publication Date	2010-06-03
	Series Editor		Series Title		Abbreviated Series Title
	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	42	Open Access
	Notes	Fwo; Iap-6			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:85784			Serial	1284
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	Author	Ke, X.; Bals, S.; Cott, D.; Hantschel, T.; Bender, H.; Van Tendeloo, G.
	Title	Three-dimensional analysis of carbon nanotube networks in interconnects by electron tomography without missing wedge artifacts			Type	A1 Journal article
	Year	2010	Publication	Microscopy and microanalysis	Abbreviated Journal	Microsc Microanal
	Volume	16	Issue	2	Pages	210-217
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The three-dimensional (3D) distribution of carbon nanotubes (CNTs) grown inside semiconductor contact holes is studied by electron tomography. The use of a specialized tomography holder results in an angular tilt range of ±90°, which means that the so-called missing wedge is absent. The transmission electron microscopy (TEM) sample for this purpose consists of a micropillar that is prepared by a dedicated procedure using the focused ion beam (FIB) but keeping the CNTs intact. The 3D results are combined with energy dispersive X-ray spectroscopy (EDS) to study the relation between the CNTs and the catalyst particles used during their growth. The reconstruction, based on the full range of tilt angles, is compared with a reconstruction where a missing wedge is present. This clearly illustates that the missing wedge will lead to an unreliable interpretation and will limit quantitative studies
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge, Mass.	Editor
	Language		Wos	000276137200011	Publication Date	2010-02-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1431-9276;1435-8115;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.891	Times cited	42	Open Access
	Notes	Esteem 026019; Fwo; Iap-Vi			Approved	Most recent IF: 1.891; 2010 IF: 3.259
	Call Number	UA @ lucian @ c:irua:82279			Serial	3642
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