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“Single-step alcohol-free synthesis of coreshell nanoparticles of \gamma-casein micelles and silica”. Kerkhofs S, Leroux F, Allouche L, Mellaerts R, Jammaer J, Aerts A, Kirschhock CEA, Magusin PCMM, Taulelle F, Bals S, Van Tendeloo G, Martens JA;, RSC advances 4, 25650 (2014). http://doi.org/10.1039/C4RA03252G
Abstract: A new, single-step protocol for wrapping individual nanosized β-casein micelles with silica is presented. This biomolecule-friendly synthesis proceeds at low protein concentration at almost neutral pH, and makes use of sodium silicate instead of the common silicon alkoxides. This way, formation of potentially protein-denaturizing alcohols can be avoided. The pH of the citrate-buffered synthesis medium is close to the isoelectric point of β-casein, which favours micelle formation. A limited amount of sodium silicate is added to the protein micelle suspension, to form a thin silica coating around the β-casein micelles. The size distribution of the resulting proteinsilica structures was characterized using DLS and SAXS, as well as 1H NMR DOSY with a dedicated pulsed-field gradient cryo-probehead to cope with the low protein concentration. The degree of silica-condensation was investigated by 29Si MAS NMR, and the nanostructure was revealed by advanced electron microscopy techniques such as ESEM and HAADF-STEM. As indicated by the combined characterization results, a silica shell of 2 nm is formed around individual β-casein micelles giving rise to separate protein coresilica shell nanoparticles of 17 nm diameter. This alcohol-free method at mild temperature and pH is potentially suited for packing protein molecules into bio-compatible silica nanocapsules for a variety of applications in biosensing, therapeutic protein delivery and biocatalysis.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.108
Times cited: 3
DOI: 10.1039/C4RA03252G
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“Au@UiO-66 : a base free oxidation catalyst”. Leus K, Concepcion P, Vandichel M, Meledina M, Grirrane A, Esquivel D, Turner S, Poelman D, Waroquier M, Van Speybroeck V, Van Tendeloo G, García H, Van Der Voort P;, RSC advances 5, 22334 (2015). http://doi.org/10.1039/c4ra16800c
Abstract: We present the in situ synthesis of Au nanoparticles within the Zr based Metal Organic Framework, UiO-66. The resulting Au@UiO-66 materials were characterized by means of N-2 sorption, XRPD, UV-Vis, XRF, XPS and TEM analysis. The Au nanoparticles (NP) are homogeneously distributed along the UiO-66 host matrix when using NaBH4 or H-2 as reducing agents. The Au@UiO-66 materials were evaluated as catalysts in the oxidation of benzyl alcohol and benzyl amine employing O-2 as oxidant. The Au@MOF materials exhibit a very high selectivity towards the ketone (up to 100%). Regenerability and stability tests demonstrate that the Au@UiO-66 catalyst can be recycled with a negligible loss of Au species and no loss of crystallinity. In situ IR measurements of UiO-66 and Au@UiO-66-NaBH4, before and after treatment with alcohol, showed an increase in IR bands that can be assigned to a combination of physisorbed and chemisorbed alcohol species. This was confirmed by velocity power spectra obtained from the molecular dynamics simulations. Active peroxo and oxo species on Au could be visualized with Raman analysis.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.108
Times cited: 38
DOI: 10.1039/c4ra16800c
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“Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations”. Bittencourt C, Krüger P, Lagos MJ, Ke X, Van Tendeloo G, Ewels C, Umek P, Guttmann P, Beilstein journal of nanotechnology 3, 789 (2012). http://doi.org/10.3762/bjnano.3.88
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.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.127
Times cited: 13
DOI: 10.3762/bjnano.3.88
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“X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge”. Bittencourt C, Hitchock AP, Ke X, Van Tendeloo G, Ewels CP, Guttmann P, Beilstein journal of nanotechnology 3, 345 (2012). http://doi.org/10.3762/bjnano.3.39
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.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.127
Times cited: 15
DOI: 10.3762/bjnano.3.39
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“Low-dose patterning of platinum nanoclusters on carbon nanotubes by focused-electron-beam-induced deposition as studied by TEM”. Ke X, Bittencourt C, Bals S, Van Tendeloo G, Beilstein journal of nanotechnology 4, 77 (2013). http://doi.org/10.3762/bjnano.4.9
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.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.127
Times cited: 12
DOI: 10.3762/bjnano.4.9
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“Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers”. Vidick D, Ke X, Devillers M, Poleunis C, Delcorte A, Moggi P, Van Tendeloo G, Hermans S, Beilstein journal of nanotechnology 6, 1287 (2015). http://doi.org/10.3762/bjnano.6.133
Abstract: Heterometal clusters containing Ru and Au, Co and/or Pt are anchored onto carbon nanotubes and nanofibers functionalized with chelating phosphine groups. The cluster anchoring yield is related to the amount of phosphine groups available on the nanocarbon surface. The ligands of the anchored molecular species are then removed by gentle thermal treatment in order to form nanoparticles. In the case of Au-containing clusters, removal of gold atoms from the clusters and agglomeration leads to a bimodal distribution of nanoparticles at the nanocarbon surface. In the case of Ru-Pt species, anchoring occurs without reorganization through a ligand exchange mechanism. After thermal treatment, ultrasmall (1-3 nm) bimetal Ru-Pt nanoparticles are formed on the surface of the nanocarbons. Characterization by high resolution transmission electron microscopy (HRTEM) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) confirms their bimetal nature on the nanoscale. The obtained bimetal nanoparticles supported on nanocarbon were tested as catalysts in ammonia synthesis and are shown to be active at low temperature and atmospheric pressure with very low Ru loading.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.127
Times cited: 7
DOI: 10.3762/bjnano.6.133
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“Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials”. Ke X, Bittencourt C, Van Tendeloo G, Beilstein journal of nanotechnology 6, 1541 (2015). http://doi.org/10.3762/bjnano.6.158
Abstract: A major revolution for electron microscopy in the past decade is the introduction of aberration correction, which enables one to increase both the spatial resolution and the energy resolution to the optical limit. Aberration correction has contributed significantly to the imaging at low operating voltages. This is crucial for carbon-based nanomaterials which are sensitive to electron irradiation. The research of carbon nanomaterials and nanohybrids, in particular the fundamental understanding of defects and interfaces, can now be carried out in unprecedented detail by aberration-corrected transmission electron microscopy (AC-TEM). This review discusses new possibilities and limits of AC-TEM at low voltage, including the structural imaging at atomic resolution, in three dimensions and spectroscopic investigation of chemistry and bonding. In situ TEM of carbon-based nanomaterials is discussed and illustrated through recent reports with particular emphasis on the underlying physics of interactions between electrons and carbon atoms.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.127
Times cited: 10
DOI: 10.3762/bjnano.6.158
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“Structure and magnetic properties of Sm(Fe,Si)(9)C/alpha-Fe nanocomposite magnets”. Bez R, Zehani K, Batuk M, Van Tendeloo G, Mliki N, Bessais L, Journal of alloys and compounds 695, 810 (2017). http://doi.org/10.1016/J.JALLCOM.2016.10.122
Abstract: SmFe8.75 Si-0.25 C/alpha-Fe nanocomposites have been successfully synthesized using high energy milling, followed by annealing at 750 degrees C. The crystal structure of these compounds was characterized by the Rietveld method using powder X-ray diffraction data. By increasing the concentration of Sm, we observed a decrease in the amount of alpha-Fe phase. The morphology of the samples was determined by scanning and transmission electron microscopy. The average grain size is about 20 nm. The magnetic properties were investigated at room temperature and at 10 K. A ferromagnetic behavior was observed in all samples at both temperatures. An increase of the soft magnetic phase alpha-Fe induced an increase in the magnetization and a decrease in coercivity. (C) 2016 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.133
Times cited: 1
DOI: 10.1016/J.JALLCOM.2016.10.122
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“Synthesis of monodispersed CoMoO4 nanoclusters on the ordered mesoporous carbons for environment-friendly supercapacitors”. Li J, Zhao C, Yang Y, Li C, Hollenkamp T, Burke N, Hu Z-Y, Van Tendeloo G, Chen W, Journal of alloys and compounds 810, 151841 (2019). http://doi.org/10.1016/J.JALLCOM.2019.151841
Abstract: Binary metal oxides with superior charge capacity and electrochemical activity have gained great interests. In this work, monodispersed CoMoO4 nanoclusters on the ordered mesoporous carbons were fabricated by a facile self-developed impregnation method. The synthesized hybrids possess improved wettability, high specific surface area (> 700m(2)/g) and regular mesoporous channels (similar to 4 nm), resulting in improved electrochemical performance for supercapacitors. These well-dispersed CoMoO4 nanoclusters exhibit a significant specific capacitance up to 367 F/g in the aqueous KNO3 electrolyte and good reversibility with a cycling efficiency of 99.8%. It is proposed that the mesoporous structure can facilitate the diffusion of electrolyte ions and then accelerate the electrochemical utilization of CoMoO4 nanoclusters. The results demonstrate that the produced binary metal oxide nanoclusters with excellent capacitance and good retention can be used as promising electrodes for the environment-friendly supercapacitors. (C) 2019 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.133
Times cited: 6
DOI: 10.1016/J.JALLCOM.2019.151841
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“Characterisation of multilayer ramp-type REBa2Cu3O7-\delta structures by scanning probe microscopy and high-resolution electron microscopy”. Blank DHA, Rijnders AJHM, Verhoeven MAJ, Bergs RMH, Rogalla H, Verbist K, Lebedev O, Van Tendeloo G, Journal of alloys and compounds
T2 –, Symposium on High Temperature Superconductor Thin Films, Growth, Mechanisms, Interfaces, Multilayers, at the 1996 Spring Meeting of the European-Materials-Society, June 04-07, 1996, Strasbourg, France 251, 206 (1997). http://doi.org/10.1016/S0925-8388(96)02799-5
Abstract: We studied the morphology of ramps in REBa2CU3O7 (REBCO) epitaxial films on SrTiO3 substrates, fabricated by RF magnetron sputter deposition and pulsed laser deposition (PLD), by scanning probe microscopy (SPM) and high resolution electron microscopy (HREM). The ramps were fabricated by Ar ion beam etching using masks of standard photoresist and TIN. AFM-studies on ramps in sputter deposited films show a strong dependence, i.e. formation of facets and ridges, on the angle of incidence of the ion beam with respect to the substrate surface as well as the rotation angle with respect to the crystal axes of the substrate. Ramps in pulsed laser deposited films did not show this dependence, Furthermore, we studied the effect of an anneal step prior to the deposition of barrier layers (i.e. PrBa2CU3O7, SrTiO3, CeO2) on the ramp. First results show a recrystallization of the ramp surface, resulting in terraces and a non-homogeneous growth of the barrier material on top of it. The thickness variations, for thin layers of barrier material, con even become much larger than expected from the amount of deposited material and are dependent on the deposition and anneal conditions. HREM studies show a well defined interface between barrier layer and electrodes. The angle of the ramp depends on the etch rate of the mask and REBCO, and on the angle of incidence of the ion beam. TiN has a much lower etch rate compared to photoresist, resulting in an angle of the ramp comparable to the angle of incidence, resulting in a low etching rate on the ramp. These results will lead to improved electrical characteristics of ramp-type junctions.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.133
DOI: 10.1016/S0925-8388(96)02799-5
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“Synthesis and structure of Ln4Re6-xO19 (Ln=Ce, Pr, Nd) complex oxides”. Bramnik KG, Abakumov AM, Shpanchenko RV, Antipov EV, Van Tendeloo G, Journal of alloys and compounds 278, 98 (1998). http://doi.org/10.1016/S0925-8388(98)00252-7
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.133
Times cited: 8
DOI: 10.1016/S0925-8388(98)00252-7
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“Influence of oxygen content on the charge-ordering process in La0.5Ca0.5MnO3”. Schuddinck W, Van Tendeloo G, Martin C, Hervieu M, Raveau B, Journal of alloys and compounds 333, 13 (2002). http://doi.org/10.1016/S0925-8388(01)01691-7
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.133
Times cited: 9
DOI: 10.1016/S0925-8388(01)01691-7
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“Pd5InSe and Pd8In2Se : new metal-rich homological selenides with 2D palladium-indium fragments : synthesis, structure and bonding”. Zakharova EY, Kazakov SM, Isaeva AA, Abakumov AM, Van Tendeloo G, Kuznetsov AN, Journal of alloys and compounds 589, 48 (2014). http://doi.org/10.1016/j.jallcom.2013.11.172
Abstract: Two new metal-rich palladium-indium selenides, Pd5InSe and Pd8In2Se, were synthesized using a high-temperature ampoule technique. Their crystal structures were determined from Rietveld analysis of powder diffraction data, supported by energy-dispersive X-ray spectroscopy and selected area electron diffraction. Both compounds crystallize in tetragonal system with P4/mmm space group (Pd5InSe: a = 4.0290(3) angstrom, c = 6.9858(5) angstrom, Z = 1; Pd8In2Se: a = 4.0045(4) angstrom, c = 10.952(1) angstrom, Z = 1). The first compound belongs to the Pd5TlAs structure type, while the second one – to a new structure type. Main structural units in both selenides are indium-centered [Pd12In] cuboctahedra of the tetragonally distorted Cu3Au type, single-and double-stacked along the c axis in Pd5InSe and Pd8In2Se, respectively, alternating with [Pd8Se] rectangular prisms. DFT electronic structure calculations predict both compounds to be 3D metallic conductors and Pauli-like paramagnets. According to the bonding analysis based on the electron localization function topology, both compounds feature multi-centered palladium-indium interactions in their heterometallic fragments. (C) 2013 Elsevier B. V. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.133
Times cited: 12
DOI: 10.1016/j.jallcom.2013.11.172
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“The influence of the alcohol concentration on the structural ordering of mesoporous silica: cosurfactant versus cosolvent”. Liu S, Cool P, Collart O, van der Voort P, Vansant EF, Lebedev OI, Van Tendeloo G, Jiang M, The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical 107, 10405 (2003). http://doi.org/10.1021/jp034410w
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Impact Factor: 3.177
Times cited: 134
DOI: 10.1021/jp034410w
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“Aluminum incorporation into MCM-48 toward the creation of Brønsted acidity”. Collart O, Cool P, van der Voort P, Meynen V, Vansant EF, Houthoofd KJ, Grobet PJ, Lebedev OI, Van Tendeloo G, The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical 108, 13905 (2004). http://doi.org/10.1021/jp049837x
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Impact Factor: 3.177
Times cited: 13
DOI: 10.1021/jp049837x
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“Structural, textural, and electronic properties of a nanosized mesoporous ZnxTi1-xO2-x solid solution prepared by a supercritical drying route”. Kolen'ko YV, Kovnir KA, Gavrilov AI, Garshev AV, Meskin PE, Churagulov BR, Bouchard M, Colbeau-Justin C, Lebedev OI, Van Tendeloo G, Yoshimura M, Journal of physical chemistry B 109, 20303 (2005). http://doi.org/10.1021/jp0535341
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.177
Times cited: 34
DOI: 10.1021/jp0535341
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“Hydrothermal synthesis and characterization of nanorods of various titanates and titanium dioxide”. Kolen'ko YV, Kovnir KA, Gavrilov AI, Garshev AV, Frantti J, Lebedev OI, Churagulov BR, Van Tendeloo G, Yoshimura M, The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical 110, 4030 (2006). http://doi.org/10.1021/jp055687u
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.177
Times cited: 234
DOI: 10.1021/jp055687u
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“Investigation of the morphology of the mesoporous SBA-16 and SBA-15 materials”. Stevens WJJ, Lebeau K, Mertens M, Van Tendeloo G, Cool P, Vansant EF, The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical 110, 9183 (2006). http://doi.org/10.1021/jp0548725
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT)
Impact Factor: 3.177
Times cited: 109
DOI: 10.1021/jp0548725
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“Ge40.0Te5.3I8: synthesis, crystal structure, and properties of a new clathrate-I compound”. Kovnir KA, Abramchuk NS, Zaikina JV, Baitinger M, Burkhardt U, Schnelle W, Olenev AV, Lebedev OI, Van Tendeloo G, Dikarev EV, Shevelkov AV, Zeitschrift für Kristallographie 221, 527 (2006). http://doi.org/10.1524/zkri.2006.221.5-7.527
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.179
Times cited: 16
DOI: 10.1524/zkri.2006.221.5-7.527
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“Energy-filtered transmission electron microscopy: an overview”. Verbeeck J, van Dyck D, Van Tendeloo G, Spectrochimica acta: part B : atomic spectroscopy 59, 1529 (2004). http://doi.org/10.1016/j.sab.2004.03.020
Abstract: This paper aims to give an overview of the technique of energy-filtered transmission electron microscopy (EFTEM). It explains the basic principles of the technique and points to the relevant literature for more detailed issues. Experimental examples are given to show the power of EFTEM to study the chemical composition of nanoscale samples in materials science. Advanced EFTEM applications like imaging spectroscopy and EFTEM tomography are briefly discussed. (C) 2004 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 3.241
Times cited: 37
DOI: 10.1016/j.sab.2004.03.020
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“Fe and Co nanowires and nanotubes synthesized by template electrodeposition: a HRTEM and EELS study”. Verbeeck J, Lebedev OI, Van Tendeloo G, Cagnon L, Bougerol C, Tourillon T, Journal of the electrochemical society 150, E468 (2003). http://doi.org/10.1149/1.1601230
Abstract: Co and Fe nanowires and/or nanotubes are electrochemically synthesized through nanoporous membranes. By combining high-resolution transmission electron microscopy (HRTEM), electron energy loss spectroscopy (EELS), and energy filtered TEM techniques, their structural and crystallographic characteristics are precisely determined. The synthesis was shown to produce cigar-shaped single monocrystalline Co and Fe nanowires with a diameter of about 60 nm. All wires were surrounded by an epitaxial oxide layer (Co3O4 or Fe3O4) of roughly 10 nm. The Fe nanotubes were built up of Fe3O4 nanocrystals. Electron diffraction showed that all nanocrystals had a common crystallographic axis, creating a pseudomonocrystalline wall in the nanotubes. (C) 2003 The Electrochemical Society.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.259
Times cited: 41
DOI: 10.1149/1.1601230
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“Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials”. McCalla E, Prakash AS, Berg E, Saubanere M, Abakumov AM, Foix D, Klobes B, Sougrati MT, Rousse G, Lepoivre F, Mariyappan S, Doublet ML, Gonbeau D, Novak P, Van Tendeloo G, Hermann RP, Tarascon JM;, Journal of the electrochemical society 162, A1341 (2015). http://doi.org/10.1149/2.0991507jes
Abstract: Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.259
Times cited: 23
DOI: 10.1149/2.0991507jes
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“Preparation and luminescence of bulk oxyfluoride glasses doped with Ag nanoclusters”. Tikhomirov VK, Rodriguez VD, Kutznetsov D, Kirilenko D, Van Tendeloo G, Moshchalkov VV, Optics express 18, 22032 (2010). http://doi.org/10.1364/OE.18.022032
Abstract: Bulk oxyfluoride glasses doped with Ag nanoclusters have been prepared using the melt quenching technique. When pumped in the absorption band of Ag nanoclusters between 300 to 500 nm, these glasses emit a very broad luminescence band covering all the visible range with a weak tail extending into the near infrared. The maximum of the luminescence band and its color shifts to the blue with a shortening of the excitation wavelength and an increasing ratio of oxide to fluoride components, resulting in white color luminescence at a particular ratio of oxide to fluoride; with a quantum yield above 20%.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.307
Times cited: 74
DOI: 10.1364/OE.18.022032
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“Quantum cutting in Li (770 nm) and Yb (1000 nm) co-dopant emission bands by energy transfer from the ZnO nano-crystalline host”. Shestakov MV, Tikhomirov VK, Kirilenko D, Kuznetsov AS, Chibotaru LF, Baranov AN, Van Tendeloo G, Moshchalkov VV, Optics express 19, 15955 (2011). http://doi.org/10.1364/OE.19.015955
Abstract: Li-Yb co-doped nano-crystalline ZnO has been synthesized by a method of thermal growth from the salt mixtures. X-ray diffraction, transmission electron microscopy, atomic absorption spectroscopy and optical spectroscopy confirm the doping and indicate that the dopants may form Li-Li and Yb3+-Li based nanoclusters. When pumped into the conduction and exciton absorption bands of ZnO between 250 to 425 nm, broad emission bands of about 100 nm half-height-width are excited around 770 and 1000 nm, due to Li and Yb dopants, respectively. These emission bands are activated by energy transfer from the ZnO host mostly by quantum cutting processes, which generate pairs of quanta in Li (770 nm) and Yb (1000 nm) emission bands, respectively, out of one quantum absorbed by the ZnO host. These quantum cutting phenomena have great potential for application in the down-conversion layers coupled to the Si solar cells.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.307
Times cited: 19
DOI: 10.1364/OE.19.015955
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“The microstructure and interfaces of intermediate layers in sapphire bicrystals”. Vasiliev AL, Stepantsov EA, Ivanov ZG, Verbist K, Van Tendeloo G, Olsson E, Applied surface science 119, 215 (1997)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.387
Times cited: 2
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“Ga segregation in DyBa2Cu3O7-\delta/PrBa2Cu3-xGaxO7-\delta/DyBa2Cu3O7-\delta ramp-type Josephson junctions”. Verbist K, Lebedev OI, Van Tendeloo G, Verhoeven MAJ, Rijnders AJHM, Blank DHA, Rogalia H, Applied physics letters 70, 1167 (1997)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 8
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“A potential method to correlate electrical properties and microstructure of a unique high-Tc superconducting Josephson junction”. Verbist K, Lebedev OI, Van Tendeloo G, Tafuri F, Granozio FM, Di Chiara A, Bender H, Applied physics letters 74, 1024 (1999). http://doi.org/10.1063/1.123443
Abstract: A method to correlate microstructure from cross-section transmission electron microscopy (TEM) investigations and transport properties of a single well characterized high-T-c artificial grain boundary junction is reported. A YBa2Cu3O7-delta 45 degrees twist junction exhibiting the typical phenomenology of high T-c Josephson weak links was employed. The TEM sample preparation is based on focused ion beam etching and allows to easily localize the electron transparent area on a microbridge. The reported technique opens clear perspectives in the determination of the microstructural origin of variations in Josephson junction properties, such as the spread in I-c and IcRN values and the presence of different transport regimes in nominally identical junctions. (C) 1999 American Institute of Physics. [S0003-6951(99)03404-X].
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 5
DOI: 10.1063/1.123443
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“Epitaxial strain induced metal insulator transition in La0.9Sr0.1MnO3 and La0.88Sr0.1MnO3 thin films”. Razavi FS, Gross G, Habermeier H-U, Lebedev O, Amelinckx S, Van Tendeloo G, Vigliante A, Applied physics letters 76, 155 (2000). http://doi.org/10.1063/1.125687
Abstract: We are reporting an unexpected metal insulator transition at the ferromagnetic phase-transition temperature for thin films of La0.9Sr0.1MnO3 (< 50 nm), grown on a (100) face of SrTiO3 substrate. For the thicker films (> 50 nm), similar to the single crystal, no such transition is observed below T-C. Additionally, we observe the suppression of the features associated with charge or orbital ordering in intentionally La-deficient thin films of La0.88Sr0.1MnO3 (< 75 nm). In thin films, transmission electron microscopy reveals a compressive strain due to the epitaxial growth, that is, lattice parameters adopt those of the cubic lattice of SrTiO3. As the film thickness increases, coherent microtwinning is observed in the films and the films relax to a orthorhombic structure. (C) 2000 American Institute of Physics. [S0003-6951(00)00402-2].
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 91
DOI: 10.1063/1.125687
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“Electron energy-loss spectroscopy study of a (LaMnO3)8(SrMnO3)4 heterostructure”. Verbeeck J, Lebedev OI, Van Tendeloo G, Silcox J, Mercey B, Hervieu M, Haghiri-Gosnet AM, Applied physics letters 79, 2037 (2001). http://doi.org/10.1063/1.1403316
Abstract: An epitaxially grown heterostructure consisting of alternating layers of LaMnO3 (8 unit cells) and SrMnO3 (4 unit cells) on a SrTiO3 substrate has been studied by a combination of electron energy-loss spectroscopy (EELS) and high-resolution transmission electron microscopy (HRTEM) on an atomic scale. Excitation edges of all elements are captured with subnanometer spatial accuracy, and parametrized to obtain chemical profiles. The fine-edge structure of O K and Mn L-2,L-3 edges are interpreted as signatures of the local electronic structure and show a spatial modulation of the concentration of holes with O 2p character. The chemical concentration is found to be different for the bottom and top interface of a SrMnO3 layer. HRTEM complements the EELS results and confirms the asymmetry of the interfaces. (C) 2001 American Institute of Physics.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 19
DOI: 10.1063/1.1403316
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“Why are sputter deposited Nd1+xBa2-xCu3O7-\delta thin films flatter than NdBa2Cu3O7-\delta films?”.Bals S, Van Tendeloo G, Salluzzo M, Maggio-Aprile I, Applied physics letters 79, 3660 (2001). http://doi.org/10.1063/1.1421622
Abstract: High-resolution electron microscopy and scanning tunneling microscopy have been used to compare the microstructure of NdBa2Cu3O7-delta and Nd1+xBa2-xCu3O7-delta thin films. Both films contain comparable amounts of Nd2CuO4 inclusions. Antiphase boundaries are induced by unit cell high steps at the substrate or by a different interface stacking. In Nd1+xBa2-xCu3O7-delta the antiphase boundaries tend to annihilate by the insertion of extra Nd layers. Stacking faults, which can be characterized as local Nd2Ba2Cu4O9 inclusions, also absorb the excess Nd. A correlation is made between the excess Nd and the absence of growth spirals at the surface of the Nd-rich films. (C) 2001 American Institute of Physics.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 13
DOI: 10.1063/1.1421622
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