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Author |
Vidick, D.; Ke, X.; Devillers, M.; Poleunis, C.; Delcorte, A.; Moggi, P.; Van Tendeloo, G.; Hermans, S. |
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Title |
Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
6 |
Issue |
6 |
Pages |
1287-1297 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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. |
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Wos |
000355908400001 |
Publication Date |
2015-06-10 |
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Series Issue |
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Edition |
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ISSN  |
2190-4286; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.127 |
Times cited |
7 |
Open Access |
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Notes |
246791 Countatoms; 262348 Esmi |
Approved |
Most recent IF: 3.127; 2015 IF: 2.670 |
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Call Number |
c:irua:126431 |
Serial |
1420 |
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Author |
Ke, X.; Bittencourt, C.; Bals, S.; Van Tendeloo, G. |
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Title |
Low-dose patterning of platinum nanoclusters on carbon nanotubes by focused-electron-beam-induced deposition as studied by TEM |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
4 |
Issue |
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Pages |
77-86 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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. |
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Wos |
000314499700001 |
Publication Date |
2013-02-04 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2190-4286; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.127 |
Times cited |
12 |
Open Access |
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Notes |
262348 ESMI; 246791 COUNTATOMS; FWO G002410N; ESF Cost Action NanoTP MP0901 |
Approved |
Most recent IF: 3.127; 2013 IF: 2.332 |
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Call Number |
UA @ lucian @ c:irua:106187 |
Serial |
1848 |
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Author |
Ke, X.; Bittencourt, C.; Van Tendeloo, G. |
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Title |
Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
6 |
Issue |
6 |
Pages |
1541-1557 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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. |
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Wos |
000357977300001 |
Publication Date |
2015-07-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2190-4286; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.127 |
Times cited |
10 |
Open Access |
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Notes |
246791 Countatoms |
Approved |
Most recent IF: 3.127; 2015 IF: 2.670 |
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Call Number |
c:irua:126857 |
Serial |
2682 |
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Author |
Mordvinova, N.; Emelin, P.; Vinokurov, A.; Dorofeev, S.; Abakumov, A.; Kuznetsova, T. |
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Title |
Surface processes during purification of InP quantum dots |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
5 |
Issue |
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Pages |
1220-1225 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)(3) during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of post-synthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular. |
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Wos |
000339912400002 |
Publication Date |
2014-08-06 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2190-4286; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.127 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.127; 2014 IF: 2.670 |
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Call Number |
UA @ lucian @ c:irua:118748 |
Serial |
3397 |
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Author |
Bittencourt, C.; Krüger, P.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Ewels, C.; Umek, P.; Guttmann, P. |
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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 |
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Year |
2012 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
3 |
Issue |
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Pages |
789-797 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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. |
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Wos |
000311482400001 |
Publication Date |
2012-11-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2190-4286; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.127 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.127; 2012 IF: 2.374 |
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Call Number |
UA @ lucian @ c:irua:105140 |
Serial |
3684 |
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Author |
Bittencourt, C.; Hitchock, A.P.; Ke, X.; Van Tendeloo, G.; Ewels, C.P.; Guttmann, P. |
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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 |
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Year |
2012 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
3 |
Issue |
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Pages |
345-350 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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. |
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Wos |
000303243400001 |
Publication Date |
2012-04-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2190-4286; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.127 |
Times cited |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.127; 2012 IF: 2.374 |
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Call Number |
UA @ lucian @ c:irua:97703 |
Serial |
3924 |
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Author |
Idrissi, H.; Samaee, V.; Lumbeeck, G.; Werf, T.; Pardoen, T.; Schryvers, D.; Cordier, P. |
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Title |
In Situ Quantitative Tensile Testing of Antigorite in a Transmission Electron Microscope |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Geophysical Research-Solid Earth |
Abbreviated Journal |
J Geophys Res-Sol Ea |
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Volume |
125 |
Issue |
3 |
Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The determination of the mechanical properties of serpentinites is essential toward the understanding of the mechanics of faulting and subduction. Here we present the first in situ tensile tests on antigorite in a transmission electron microscope. A push‐to‐pull deformation device is used to perform quantitative tensile tests, during which force and displacement are measured, while the evolving microstructure is imaged with the microscope. The experiments have been performed at room temperature on 2 × 1 × 0.2 μm3 beams prepared by focused ion beam. The specimens are not single crystals despite their small sizes. Orientation mapping indicated that several grains were well oriented for plastic slip. However, no dislocation activity has been observed even though the engineering tensile stress went up to 700 MPa. We show also that antigorite does not exhibit a purely elastic‐brittle behavior since, despite the presence of defects, the specimens accumulate permanent deformation and did not fail within the elastic regime. Instead, we observe that strain localizes at grain boundaries. All observations concur to show that under these experimental conditions, grain boundary sliding is the dominant deformation mechanism. This study sheds a new light on the mechanical properties of antigorite and calls for further studies on the structure and properties of grain boundaries in antigorite and more generally in phyllosilicates. |
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Wos |
000530895800023 |
Publication Date |
2020-02-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2169-9313 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.9 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
We thank S. Guillot for having kindly provided us with the two antigorite samples investigated in this study. We acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program under Grant Agreement 787198—TimeMan. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR‐FNRS). We acknowledge fruitful discussions with A. Baronnet. We thank J. Gasc and an anonymous reviewer for their critical comments. Data (movies of the three in situ deformation experiments) can be downloaded (from https://doi.org/10.5281/zenodo.3583135). |
Approved |
Most recent IF: 3.9; 2020 IF: 3.35 |
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Call Number |
EMAT @ emat @c:irua:167594 |
Serial |
6355 |
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Author |
Queralto, A.; Graf, D.; Frohnhoven, R.; Fischer, T.; Vanrompay, H.; Bals, S.; Bartasyte, A.; Mathur, S. |
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Title |
LaFeO3 nanofibers for high detection of sulfur-containing gases |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
ACS Sustainable Chemistry and Engineering |
Abbreviated Journal |
Acs Sustain Chem Eng |
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Volume |
7 |
Issue |
7 |
Pages |
6023-6032 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Lanthanum ferrite nanofibers were electrospun from a chemical sol and calcined at 600 degrees C to obtain singlephase LaFeO3 (LFO) perovskite. High-resolution transmission electron microscopy in conjunction with 3D tomographic analysis confirmed an interwoven network of hollow and porous (surface) LFO nanofibers. Owing to their high surface area and p-type behavior, the nanofiber meshes showed high chemoselectivity toward reducing toxic gases (SO2, H2S) that could be reproducibly detected at very low concentrations (<1 ppm), well below the threshold values for occupational safety and health. An increased sensitivity was observed in the temperature range of 150-300 degrees C with maximum sensor response at 250 degrees C. The surface reaction at the heterogeneous solid (LFO)/gas (SO2) interface that confirmed the formation of La-2(SO4)(3) was investigated by X-ray photoelectron spectroscopy. Moreover, the LFO fibers showed a high selectivity in the detection of oxidizing and reducing gases. Whereas superior detection of NH3 and H2S was measured, little response was observed for CO and NO2. Finally, the integration of nanowire meshes in commercial sensor platforms was successfully demonstrated. |
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Wos |
000461978200047 |
Publication Date |
2019-02-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2168-0485 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.951 |
Times cited |
41 |
Open Access |
OpenAccess |
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Notes |
; The authors kindly acknowledge the ERA.Net RUS Plus project FONSENS funded by the German Federal Ministry of Education and Research (BMBF) under the grant no. 01DJ16017. A.Q. highly appreciates the support of the Alexander von Humboldt Foundation (grant no. AVH 1184642) and the BMBF for his postdoctoral fellowship. A.Q., D.G., R.F., T.F., and S.M. also kindly acknowledge the financial support of the University of Cologne. H.V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS). We also express our gratitude to Prof. Dr. J. Hadermann from the Electron Microscopy for Materials Science group at the University of Antwerp for her assistance. A.B. is grateful for the EUR EIPHI program (grant no. ANR-17-EURE-0002). ; |
Approved |
Most recent IF: 5.951 |
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Call Number |
UA @ admin @ c:irua:158535 |
Serial |
5263 |
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Author |
Zhang, Y.; Qin, S.; Claes, N.; Schilling, W.; Sahoo, P.K.; Ching, H.Y.V.; Jaworski, A.; Lemière, F.; Slabon, A.; Van Doorslaer, S.; Bals, S.; Das, S. |
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Title |
Direct Solar Energy-Mediated Synthesis of Tertiary Benzylic Alcohols Using a Metal-Free Heterogeneous Photocatalyst |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
ACS Sustainable Chemistry and Engineering |
Abbreviated Journal |
Acs Sustain Chem Eng |
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Volume |
10 |
Issue |
1 |
Pages |
530-540 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Organic synthesis (ORSY) |
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Abstract |
Direct hydroxylation via the functionalization of tertiary benzylic C(sp3)-H bond is of great significance for obtaining tertiary alcohols which find wide applications in pharmaceuticals as well as in fine chemical industries. However, current synthetic procedures use toxic reagents and therefore, the development of a sustainable strategy for the synthesis of tertiary benzyl alcohols is highly desirable. To solve this problem, herein, we report a metal-free
heterogeneous photocatalyst to synthesize the hydroxylated products using oxygen as the key reagent. Various benzylic substrates were employed into our mild reaction conditions to afford the desirable products in good to excellent yields. More importantly, gram-scale reaction was achieved via harvesting direct solar energy and exhibited high quantity of the product. The high stability of the catalyst was proved via recycling the catalyst and spectroscopic analyses. Finally, a possible mechanism was proposed based on the EPR and other experimental
evidence. |
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Wos |
000736518000001 |
Publication Date |
2022-01-10 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2168-0485 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.4 |
Times cited |
24 |
Open Access |
OpenAccess |
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Notes |
We thank BOF joint PhD grant (to Y. Z.), Francqui Foundation and FWO research grant (to S.D.), Chinese Scholarship Council (to Y.Z.). A.S. would like to thank the Swedish Energy Agency for financial support (project nr: 5050-1). The SEM microscope was partly funded by the Hercules Fund from the Flemish Government. |
Approved |
Most recent IF: 8.4 |
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Call Number |
EMAT @ emat @c:irua:184744 |
Serial |
6900 |
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Author |
Blandy, J.N.; Abakumov, A.M.; Christensen, K.E.; Hadermann, J.; Adamson, P.; Cassidy, S.J.; Ramos, S.; Free, D.G.; Cohen, H.; Woodruff, D.N.; Thompson, A.L.; Clarke, S.J.; |
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Title |
Soft chemical control of the crystal and magnetic structure of a layered mixed valent manganite oxide sulfide |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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Volume |
3 |
Issue |
3 |
Pages |
041520 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Oxidative deintercalation of copper ions from the sulfide layers of the layered mixed-valent manganite oxide sulfide Sr2MnO2Cu1.5S2 results in control of the copper-vacancy modulated superstructure and the ordered arrangement of magnetic moments carried by the manganese ions. This soft chemistry enables control of the structures and properties of these complex materials which complement mixed-valent perovskite and perovskite-related transition metal oxides. (C) 2015 Author(s). |
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Wos |
000353828400027 |
Publication Date |
2015-04-21 |
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Edition |
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|
| |
ISSN |
2166-532X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.335 |
Times cited |
5 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 4.335; 2015 IF: NA |
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| |
Call Number |
c:irua:126021 |
Serial |
3049 |
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| Permanent link to this record |
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Author |
Hoek, M.; Coneri, F.; Poccia, N.; Renshaw Wang, X.; Ke, X.; Van Tendeloo, G.; Hilgenkamp, H. |
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| |
Title |
Strain accommodation through facet matching in La1.85Sr0.15CuO4/Nd1.85Ce0.15CuO4 ramp-edge junctions |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
|
| |
Volume |
3 |
Issue |
3 |
Pages |
086101 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Scanning nano-focused X-ray diffraction and high-angle annular dark-field scanning transmission electron microscopy are used to investigate the crystal structure of ramp-edge junctions between superconducting electron-doped Nd1.85Ce0.15CuO4 and superconducting hole-doped La1.85Sr0.15CuO4 thin films, the latter being the top layer. On the ramp, a new growth mode of La1.85Sr0.15CuO4 with a 3.3° tilt of the c-axis is found. We explain the tilt by developing a strain accommodation model that relies on facet matching, dictated by the ramp angle, indicating that a coherent domain boundary is formed at the interface. The possible implications of this growth mode for the creation of artificial domains in morphotropic materials are discussed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000360656800009 |
Publication Date |
2015-08-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
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| |
ISSN |
2166-532X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.335 |
Times cited |
4 |
Open Access |
|
|
| |
Notes |
312483 Esteem2; 246791 Countatoms; esteem2_jra2 |
Approved |
Most recent IF: 4.335; 2015 IF: NA |
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| |
Call Number |
c:irua:127690 c:irua:127690 |
Serial |
3163 |
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| Permanent link to this record |
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Author |
Leusink, D.P.; Coneri, F.; Hoek, M.; Turner, S.; Idrissi, H.; Van Tendeloo, G.; Hilgenkamp, H. |
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Title |
Thin films of the spin ice compound Ho2Ti2O7 |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
|
| |
Volume |
2 |
Issue |
3 |
Pages |
032101-32107 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The pyrochlore compounds Ho2Ti2O7 and Dy2Ti2O7 show an exotic form of magnetism called the spin ice state, resulting from the interplay between geometrical frustration and ferromagnetic coupling. A fascinating feature of this state is the appearance of magnetic monopoles as emergent excitations above the degenerate ground state. Over the past years, strong effort has been devoted to the investigation of these monopoles and other properties of the spin ice state in bulk crystals. Here, we report the fabrication of Ho2Ti2O7 thin films using pulsed laser deposition on yttria-stabilized ZrO2 substrates. We investigated the structural properties of these films by X-ray diffraction, scanning transmission electron microscopy, and atomic force microscopy, and the magnetic properties by vibrating sample magnetometry at 2 K. The films not only show a high crystalline quality, but also exhibit the hallmarks of a spin ice: a pronounced magnetic anisotropy and an intermediate plateau in the magnetization along the [111] crystal direction. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000334220300002 |
Publication Date |
2014-03-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
2166-532X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.335 |
Times cited |
18 |
Open Access |
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| |
Notes |
The authors acknowledge support from the Dutch FOM and NWO foundations and from the European Union under the Framework 7 program under a contract from an Integrated Infrastructure Initiative (Reference 312483 ESTEEM2). G.V.T. acknowledges the ERC Grant N246791- COUNTATOMS. S.T. gratefully acknowledges financial support from the Fund for Scientific Research Flanders (FWO). H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs under Contract No. P7/21. The microscope used in this study was partially financed by the Hercules Foundation of the Flemish Government. The authors acknowledge fruitful interactions with A. Brinkman, M. G. Blamire, M. Egilmez, F. J. G. Roesthuis, J. N. Beukers, C. G. Molenaar, M. Veldhorst, and X. Renshaw Wang; esteem2_ta |
Approved |
Most recent IF: 4.335; 2014 IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:115555 |
Serial |
3641 |
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| Permanent link to this record |
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Author |
Rizzo, F.; Augieri, A.; Angrisani Armenio, A.; Galluzzi, V.; Mancini, A.; Pinto, V.; Rufoloni, A.; Vannozzi, A.; Bianchetti, M.; Kursumovic, A.; MacManus-Driscoll, J.L.; Meledin, A.; Van Tendeloo, G.; Celentano, G. |
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| |
Title |
Enhanced 77K vortex-pinning in YBa2Cu3O7−x films with Ba2YTaO6 and mixed Ba2YTaO6 + Ba2YNbO6 nano-columnar inclusions with irreversibility field to 11T |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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| |
Volume |
4 |
Issue |
4 |
Pages |
061101 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Pulsed laser deposited thin YBa2Cu3O7−x (YBCO) films with pinning additions of 5at.% Ba2YTaO6 (BYTO) were compared to films with 2.5at.% Ba2YTaO6 + 2.5at.% Ba2YNbO6 (BYNTO) additions. Excellent magnetic flux-pinning at 77 K was obtained with remarkably high irreversibility fields greater than 10T (YBCO-BYTO) and 11T (YBCO-BYNTO), representing the highest ever achieved values in YBCO films. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000379042400002 |
Publication Date |
2016-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2166-532X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.335 |
Times cited |
19 |
Open Access |
|
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| |
Notes |
This work was financially supported by EUROTAPES, a collaborative project funded by the European Commission’s Seventh Framework Program (FP7 / 2007-2013) under Grant Agreement no. 280432 |
Approved |
Most recent IF: 4.335 |
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| |
Call Number |
c:irua:133785 |
Serial |
4077 |
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| Permanent link to this record |
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Author |
Benetti, G.; Cavaliere, E.; Canteri, A.; Landini, G.; Rossolini, G.M.; Pallecchi, L.; Chiodi, M.; Van Bael, M.J.; Winckelmans, N.; Bals, S.; Gavioli, L. |
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Title |
Direct synthesis of antimicrobial coatings based on tailored bi-elemental nanoparticles |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
|
| |
Volume |
5 |
Issue |
5 |
Pages |
036105 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Ultrathin coatings based on bi-elemental nanoparticles (NPs) are very promising to limit the surface-related spread of bacterial pathogens, particularly in nosocomial environments. However, tailoring the synthesis, composition, adhesion to substrate, and antimicrobial spectrum of the coating is an open challenge. Herein, we report on a radically new nanostructured coating, obtained by a one-step gas-phase deposition technique, and composed of bi-elemental Janus type Ag/Ti NPs. The NPs are characterized by a cluster-in-cluster mixing phase with metallic Ag nano-crystals embedded in amorphous TiO2 and present a promising antimicrobial activity including also multidrug resistant strains. We demonstrate the flexibility of the method to tune the embedded Ag nano-crystals dimension, the total relative composition of the coating, and the substrate type, opening the possibility of tailoring the dimension, composition, antimicrobial spectrum, and other physical/chemical properties of such multi-elemental systems. This work is expected to significantly spread the range of applications of NPs coatings, not only as an effective tool in the prevention of healthcare-associated infections but also in other technologically relevant fields like sensors or nano-/micro joining. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000398951000014 |
Publication Date |
2017-03-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2166-532X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.335 |
Times cited |
21 |
Open Access |
OpenAccess |
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| |
Notes |
We thank Urs Gfeller for the XRF measurements, Francesco Banfi for valuable discussions on the manuscript and Giulio Viano for his valuable support in the microbiological analysis. The authors acknowledge the financial support of Universita Cattolica del Sacro Cuore through D.2.2 and D.3.1 grants and from the European Union through the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). REFERENCES |
Approved |
Most recent IF: 4.335 |
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| |
Call Number |
EMAT @ emat @ c:irua:141723UA @ admin @ c:irua:141723 |
Serial |
4479 |
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| Permanent link to this record |
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Author |
Ramaneti, R.; Sankaran, K.J.; Korneychuk, S.; Yeh, C.J.; Degutis, G.; Leou, K.C.; Verbeeck, J.; Van Bael, M.K.; Lin, I.N.; Haenen, K. |
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Title |
Vertically aligned diamond-graphite hybrid nanorod arrays with superior field electron emission properties |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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| |
Volume |
5 |
Issue |
6 |
Pages |
066102 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
A “patterned-seeding technique” in combination with a “nanodiamond masked reactive ion etching process” is demonstrated for fabricating vertically aligned diamond-graphite hybrid (DGH) nanorod arrays. The DGH nanorod arrays possess superior field electron emission (FEE) behavior with a low turn-on field, long lifetime stability, and large field enhancement factor. Such an enhanced FEE is attributed to the nanocomposite nature of theDGHnanorods, which contain sp(2)-graphitic phases in the boundaries of nano-sized diamond grains. The simplicity in the nanorod fabrication process renders the DGH nanorods of greater potential for the applications as cathodes in field emission displays and microplasma display devices. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000404623000002 |
Publication Date |
2017-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2166-532x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.335 |
Times cited |
16 |
Open Access |
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| |
Notes |
The authors would like to thank the Methusalem “NANO” network for financial support and Mr. B. Ruttens and Professor Jan D'Haen for technical and experimental assistance. K.J. Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). |
Approved |
Most recent IF: 4.335 |
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| |
Call Number |
UA @ admin @ c:irua:152633 |
Serial |
5369 |
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| Permanent link to this record |
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Author |
Do, M.T.; Gauquelin, N.; Nguyen, M.D.; Blom, F.; Verbeeck, J.; Koster, G.; Houwman, E.P.; Rijnders, G. |
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Title |
Interface degradation and field screening mechanism behind bipolar-cycling fatigue in ferroelectric capacitors |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Apl Materials |
Abbreviated Journal |
Apl Mater |
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| |
Volume |
9 |
Issue |
2 |
Pages |
021113 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Polarization fatigue, i.e., the loss of polarization of ferroelectric capacitors upon field cycling, has been widely discussed as an interface related effect. However, mechanism(s) behind the development of fatigue have not been fully identified. Here, we study the fatigue mechanisms in Pt/PbZr0.52Ti0.48O3/SrRuO3 (Pt/PZT/SRO) capacitors in which all layers are fabricated by pulsed laser deposition without breaking the vacuum. With scanning transmission electron microscopy, we observed that in the fatigued capacitor, the Pt/PZT interface becomes structurally degraded, forming a 5 nm-10 nm thick non-ferroelectric layer of crystalline ZrO2 and diffused Pt grains. We then found that the fatigued capacitors can regain the full initial polarization switching if the externally applied field is increased to at least 10 times the switching field of the pristine capacitor. These findings suggest that polarization fatigue is driven by a two-step mechanism. First, the transient depolarization field that repeatedly appears during the domain switching under field cycling causes decomposition of the metal/ferroelectric interface, resulting in a non-ferroelectric degraded layer. Second, this interfacial non-ferroelectric layer screens the external applied field causing an increase in the coercive field beyond the usually applied maximum field and consequently suppresses the polarization switching in the cycled capacitor. Our work clearly confirms the key role of the electrode/ferroelectric interface in the endurance of ferroelectric-based devices. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000630052100006 |
Publication Date |
2021-02-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
2166-532x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.335 |
Times cited |
5 |
Open Access |
OpenAccess |
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| |
Notes |
This work was supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek through Grant No. F62.3.15559. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government. N.G. and J.V. acknowledge funding from the GOA project “Solarpaint” of the University of Antwerp. This work has also received funding from the European Union's Horizon 2020 research and innovation program under Grant No. 823717-ESTEEM3. We acknowledge D. Chezganov for his useful insights. |
Approved |
Most recent IF: 4.335 |
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| |
Call Number |
UA @ admin @ c:irua:177663 |
Serial |
6783 |
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| Permanent link to this record |
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Author |
Verdierre, G.; Gauquelin, N.; Jannis, D.; Birkhölzer, Y.A.; Mallik, S.; Verbeeck, J.; Bibes, M.; Koster, G. |
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Title |
Epitaxial growth of the candidate ferroelectric Rashba material SrBiO3by pulsed laser deposition |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
APL materials |
Abbreviated Journal |
|
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| |
Volume |
11 |
Issue |
3 |
Pages |
031109 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Among oxides, bismuthates have been gaining much interest due to their unique features. In addition to their superconducting properties, they show potential for applications as topological insulators and as possible spin-to-charge converters. After being first investigated in their bulk form in the 1980s, bismuthates have been successfully grown as thin films. However, most efforts have focused on BaBiO<sub>3</sub>, with SrBiO<sub>3</sub>receiving only little attention. Here, we report the growth of epitaxial films of SrBiO<sub>3</sub>on both TiO<sub>2</sub>-terminated SrTiO<sub>3</sub>and NdO-terminated NdScO<sub>3</sub>substrates by pulsed laser deposition. SrBiO<sub>3</sub>has a pseudocubic lattice constant of ∼4.25 Å and grows relaxed on NdScO<sub>3</sub>. Counter-intuitively, it grows with a slight tensile strain on SrTiO<sub>3</sub>despite a large lattice mismatch, which should induce compressive strain. High-resolution transmission electron microscopy reveals that this occurs as a consequence of structural domain matching, with blocks of 10 SrBiO<sub>3</sub>unit planes matching blocks of 11 SrTiO<sub>3</sub>unit planes. This work provides a framework for the synthesis of high quality perovskite bismuthates films and for the understanding of their interface interactions with homostructural substrates. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000953363800004 |
Publication Date |
2023-03-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
2166-532X |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
6.1 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
This work received support from the ERC Advanced grant (Grant No. 833973) “FRESCO” and funding from the European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No. 823717—ESTEEM3, Van Gogh travel grant, Nuffic, The Netherlands (CF No. 42582SB).; esteem3reported; esteem3TA |
Approved |
Most recent IF: 6.1; 2023 IF: 4.335 |
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Call Number |
EMAT @ emat @c:irua:196135 |
Serial |
7377 |
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| Permanent link to this record |
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Author |
Ignatova, K.; Vlasov, E.; Seddon, S.D.; Gauquelin, N.; Verbeeck, J.; Wermeille, D.; Bals, S.; Hase, T.P.A.; Arnalds, U.B. |
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Title |
Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
APL Materials |
Abbreviated Journal |
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| |
Volume |
12 |
Issue |
4 |
Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
We present an investigation of the microstructure changes in V2O3 as it goes through its inherent structural phase transition. Using V2O3 films with a well-defined crystal structure deposited by reactive magnetron sputtering on r-plane Al2O3 substrates, we study the phase coexistence region and its impact on the surface roughness of the films and the magnetic properties of overlying Ni magnetic layers in V2O3/Ni hybrid magnetic heterostructures. The simultaneous presence of two phases in V2O3 during its structural phase transition was identified with high resolution x-ray diffraction and led to an increase in surface roughness observed using x-ray reflectivity. The roughness reaches its maximum at the midpoint of the transition. In V2O3/Ni hybrid heterostructures, we find a concomitant increase in the coercivity of the magnetic layer correlated with the increased roughness of the V2O3 surface. The chemical homogeneity of the V2O3 is confirmed through transmission electron microscopy analysis. High-angle annular dark field imaging and electron energy loss spectroscopy reveal an atomically flat interface between Al2O3 and V2O3, as well as a sharp interface between V2O3 and Ni. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001202661800003 |
Publication Date |
2024-04-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2166-532X |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
6.1 |
Times cited |
|
Open Access |
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| |
Notes |
This work was supported by the funding from the University of Iceland Research Fund, the Icelandic Research Fund Grant No. 207111. Instrumentation funding from the Icelandic Infrastructure Fund is acknowledged. This work was based on experiments per- formed at the BM28 (XMaS) beamline at the European Synchrotron Radiation Facility, Grenoble, France. XMaS is a National Research Facility funded by the UK EPSRC and managed by the Universi- ties of Liverpool and Warwick. This project has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717—ESTEEM3. |
Approved |
Most recent IF: 6.1; 2024 IF: 4.335 |
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Call Number |
EMAT @ emat @c:irua:205569 |
Serial |
9120 |
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Author |
Mahr, C.; Müller-Caspary, K.; Graf, M.; Lackmann, A.; Grieb, T.; Schowalter, M.; Krause, F.F.; Mehrtens, T.; Wittstock, A.; Weissmueller, J.; Rosenauer, A. |
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Title |
Measurement of local crystal lattice strain variations in dealloyed nanoporous gold |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Materials research letters |
Abbreviated Journal |
Mater Res Lett |
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| |
Volume |
6 |
Issue |
1 |
Pages |
84-92 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Reversible macroscopic length changes in nanoporous structures can be achieved by applying electric potentials or by exposing them to different gases or liquids. Thus, these materials are interesting candidates for applications as sensors or actuators. Macroscopic length changes originate from microscopic changes of crystal lattice parameters. In this report, we show spatially resolved measurements of crystal lattice strain in dealloyed nanoporous gold. The results confirm theory by indicating a compression of the lattice along the axis of cylindrically shaped ligaments and an expansion in radial direction. Furthermore, we show that curved npAu surfaces show inward relaxation of the surface layer. [GRAPHICS] . |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Taylor & Francis |
Place of Publication |
Abingdon |
Editor |
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Language |
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Wos |
000428141500013 |
Publication Date |
2017-11-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2166-3831 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.773 |
Times cited |
4 |
Open Access |
Not_Open_Access |
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| |
Notes |
; This work has been supported by the Deutsche Forschungsgemeinschaft (DFG) under contracts no. RO2057/12-1 (SP 6), WI4497/1-1 (SP 2) and WE1424/17-1 (SP 3) within the research unit FOR2213 (www.nagocat.de). K.M.-C acknowledges support by the DFG under contract no. MU3660/1-1 and T.G. under contract no. RO2057/ 11-1. ; |
Approved |
Most recent IF: 4.773 |
|
| |
Call Number |
UA @ lucian @ c:irua:150921 |
Serial |
4973 |
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| Permanent link to this record |
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| |
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Author |
Bliokh, K.Y.; Schattschneider, P.; Verbeeck, J.; Nori, F. |
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| |
Title |
Electron vortex beams in a magnetic field : a new twist on Landau levels and Aharonov-Bohm states |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
|
| |
Volume |
2 |
Issue |
4 |
Pages |
041011-41015 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We examine the propagation of the recently discovered electron vortex beams in a longitudinal magnetic field. We consider both the Aharonov-Bohm configuration with a single flux line and the Landau case of a uniform magnetic field. While stationary Aharonov-Bohm modes represent Bessel beams with flux- and vortex-dependent probability distributions, stationary Landau states manifest themselves as nondiffracting Laguerre-Gaussian beams. Furthermore, the Landau-state beams possess field- and vortex-dependent phases: (i) the Zeeman phase from coupling the quantized angular momentum to the magnetic field and (ii) the Gouy phase, known from optical Laguerre-Gaussian beams. Remarkably, together these phases determine the structure of Landau energy levels. This unified Zeeman-Landau-Gouy phase manifests itself in a nontrivial evolution of images formed by various superpositions of modes. We demonstrate that, depending on the chosen superposition, the image can rotate in a magnetic field with either (i) Larmor, (ii) cyclotron (double-Larmor), or (iii) zero frequency. At the same time, its centroid always follows the classical cyclotron trajectory, in agreement with the Ehrenfest theorem. Interestingly, the nonrotating superpositions reproduce stable multivortex configurations that appear in rotating superfluids. Our results open an avenue for the direct electron-microscopy observation of fundamental properties of free quantum-electron states in magnetic fields. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
College Park, Md |
Editor |
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| |
Language |
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Wos |
000311551100001 |
Publication Date |
2012-11-26 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
2160-3308; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
12.789 |
Times cited |
130 |
Open Access |
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|
| |
Notes |
Vortex ECASJO_; |
Approved |
Most recent IF: 12.789; 2012 IF: 6.711 |
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| |
Call Number |
UA @ lucian @ c:irua:105139UA @ admin @ c:irua:105139 |
Serial |
991 |
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| Permanent link to this record |
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| |
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Author |
Wu, S.; Luo, X.; Turner, S.; Peng, H.; Lin, W.; Ding, J.; David, A.; Wang, B.; Van Tendeloo, G.; Wang, J.; Wu, T.; |
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| |
Title |
Nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
|
| |
Volume |
3 |
Issue |
4 |
Pages |
041027-14 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Resistive switching heterojunctions, which are promising for nonvolatile memory applications, usually share a capacitorlike metal-oxide-metal configuration. Here, we report on the nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures, where the conducting layer near the LaAlO3/SrTiO3 interface serves as the unconventional bottom electrode although both oxides are band insulators. Interestingly, the switching between low-resistance and high-resistance states is accompanied by reversible transitions between tunneling and Ohmic characteristics in the current transport perpendicular to the planes of the heterojunctions. We propose that the observed resistive switching is likely caused by the electric-field-induced drift of charged oxygen vacancies across the LaAlO3/SrTiO3 interface and the creation of defect-induced gap states within the ultrathin LaAlO3 layer. These metal-oxide-oxide heterojunctions with atomically smooth interfaces and defect-controlled transport provide a platform for the development of nonvolatile oxide nanoelectronics that integrate logic and memory devices. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
College Park, Md |
Editor |
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| |
Language |
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Wos |
000328862400001 |
Publication Date |
2013-12-17 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2160-3308; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
12.789 |
Times cited |
77 |
Open Access |
|
|
| |
Notes |
FWO;FP7;IFOX; Countatoms; Hercules |
Approved |
Most recent IF: 12.789; 2013 IF: 8.463 |
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| |
Call Number |
UA @ lucian @ c:irua:112524 |
Serial |
2365 |
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| Permanent link to this record |
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Author |
Sankaran, K.J.; Deshmukh, S.; Korneychuk, S.; Yeh, C.-J.; Thomas, J.P.; Drijkoningen, S.; Pobedinskas, P.; Van Bael, M.K.; Verbeeck, J.; Leou, K.-C.; Leung, K.-T.; Roy, S.S.; Lin, I.-N.; Haenen, K. |
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Title |
Fabrication, microstructure, and enhanced thermionic electron emission properties of vertically aligned nitrogen-doped nanocrystalline diamond nanorods |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
MRS communications |
Abbreviated Journal |
Mrs Commun |
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| |
Volume |
8 |
Issue |
3 |
Pages |
1311-1320 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Vertically aligned nitrogen-doped nanocrystalline diamond nanorods are fabricated from nitrogen-doped nanocrystalline diamond films using reactive ion etching in oxygen plasma. These nanorods show enhanced thermionic electron emission (TEE) characteristics, viz.. a high current density of 12.0 mA/cm(2) and a work function value of 4.5 eV with an applied voltage of 3 Vat 923 K. The enhanced TEE characteristics of these nanorods are ascribed to the induction of nanographitic phases at the grain boundaries and the field penetration effect through the local field enhancement from nanorods owing to a high aspect ratio and an excellent field enhancement factor. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000448887900089 |
Publication Date |
2018-08-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
2159-6859; 2159-6867 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.01 |
Times cited |
1 |
Open Access |
|
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| |
Notes |
The authors thank the financial support of the Research Foundation Flanders (FWO) via Research Grant 12I8416N and Research Project 1519817N, and the Methusalem “NANO” network. The Hercules Foundation Flanders is acknowledged for financial support of the Raman equipment. The Qu-Ant-EM microscope used for the TEM experiments was partly funded by the Hercules fund from the Flemish Government. S.K. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. K.J. Sankaran and P. Pobedinskas are Postdoctoral Fellows of FWO. |
Approved |
Most recent IF: 3.01 |
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| |
Call Number |
UA @ admin @ c:irua:155521 |
Serial |
5364 |
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| Permanent link to this record |
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Author |
Kuznetsov, A.S.; Lu, Y.-G.; Turner, S.; Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Verbeeck, J.; Baranov, A.N.; Moshchalkov, V.V. |
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Title |
Preparation, structural and optical characterization of nanocrystalline ZnO doped with luminescent Ag-nanoclusters |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Optical materials express |
Abbreviated Journal |
Opt Mater Express |
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| |
Volume |
2 |
Issue |
6 |
Pages |
723-734 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nanocrystalline ZnO doped with Ag-nanoclusters has been synthesized by a salt solid state reaction. Three overlapping broad emission bands due to the Ag nanoclusters have been detected at about 570, 750 and 900 nm. These emission bands are excited by an energy transfer from the exciton state of the ZnO host when pumped in the wavelength range from 250 to 400 nm. The 900 nm emission band shows characteristic orbital splitting into three components pointing out that the anisotropic crystalline wurtzite host of ZnO is responsible for this feature. Heat-treatment and temperature dependence studies confirm the origin of these emission bands. An energy level diagram for the emission process and a model for Ag nanoclusters sites are suggested. The emission of nanocrystalline ZnO doped with Ag nanoclusters may be applied for white light generation, displays driven by UV light, down-convertors for solar cells and luminescent lamps. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000304953700004 |
Publication Date |
2012-04-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
2159-3930; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.591 |
Times cited |
|
Open Access |
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| |
Notes |
We are grateful to the Methusalem Funding of Flemish Government for the support of this work. Y.-G. L. and S. T. acknowledge funding from the Fund for Scientific Research Flanders (FWO) for a postdoctoral grant and under grant number G056810N. The microscope used in this study was partially financed by the Hercules Foundation. J.V. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No246791 – COUNTATOMS and ERC Starting Grant 278510 VORTEX. The authors acknowledge the guidance of Prof. G. Van Tendeloo, EMAT Antwerpen University, in transmission electron microscopy study in this work. ECASJO_; |
Approved |
Most recent IF: 2.591; 2012 IF: 2.616 |
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Call Number |
UA @ lucian @ c:irua:97709UA @ admin @ c:irua:97709 |
Serial |
2707 |
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| Permanent link to this record |
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Author |
Gauquelin, N.; Zhang, H.; Zhu, G.; Wei, J.Y.T.; Botton, G.A. |
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Title |
Atomic-scale identification of novel planar defect phases in heteroepitaxial YBa2Cu3O7-\delta thin films |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
AIP advances |
Abbreviated Journal |
Aip Adv |
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| |
Volume |
8 |
Issue |
5 |
Pages |
055022 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We have discovered two novel types of planar defects that appear in heteroepitaxial YBa2Cu3O7-delta(YBCO123) thin films, grown by pulsed-laser deposition (PLD) either with or without a La2/3Ca1/3MnO3 (LCMO) overlayer, using the combination of highangle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging and electron energy loss spectroscopy (EELS) mapping for unambiguous identification. These planar lattice defects are based on the intergrowth of either a BaO plane between two CuO chains or multiple Y-O layers between two CuO2 planes, resulting in non-stoichiometric layer sequences that could directly impact the high-Tc superconductivity. (C) 2018 Author(s). |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
Melville, NY |
Editor |
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Language |
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Wos |
000433954000022 |
Publication Date |
2018-05-21 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
2158-3226 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.568 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
; We are thankful to Julia Huang for FIB TEM sample preparation. This work is supported by NSERC (through Discovery Grants to GAB and JYTW) and CIFAR. The electron microscopy work was carried out at the Canadian Centre for Electron Microscopy, a National Facility supported by McMaster University, the Canada Foundation for Innovation and NSERC. N.G. acknowledges H. Idrissi for useful discussions. ; |
Approved |
Most recent IF: 1.568 |
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| |
Call Number |
UA @ lucian @ c:irua:152063 |
Serial |
5013 |
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| Permanent link to this record |
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Author |
Maccato, C.; Simon, Q.; Carraro, G.; Barreca, D.; Gasparotto, A.; Lebedev, O.I.; Turner, S.; Van Tendeloo, G. |
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Title |
Zinc and copper oxides functionalized with metal nanoparticles : an insight into their nano-organization |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of advanced microscopy research |
Abbreviated Journal |
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| |
Volume |
7 |
Issue |
2 |
Pages |
84-90 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Ag/ZnO and Au/CuxO (x = 1, 2) nanocomposites supported on Si(100) and polycrystalline Al2O3 were synthesised by hybrid approaches, combining chemical vapor deposition (either thermal or plasma-assisted) of host oxide matrices and subsequent radio frequency-sputtering of guest metal particles. The influence of the adopted synthetic parameters on the nanocomposite morphological and compositional features was investigated by field emission-scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Results confirm the synthesis of ZnO and CuxO nanoarchitectures, characterized by a tailored morphology and an intimate metal/oxide contact. A careful control of the processing conditions enabled a fine tuning of the mutual constituent distribution, opening thus attractive perspectives for the engineering of advanced nanomaterials. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2012-12-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2156-7573;2156-7581; |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
Esteem |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:105298 |
Serial |
3932 |
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| Permanent link to this record |
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Author |
Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Turner, S.; Van Tendeloo, G. |
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Title |
Fabrication and Characterization of Fe2O3-Based Nanostructures Functionalized with Metal Particles and Oxide Overlayers |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of advanced microscopy research |
Abbreviated Journal |
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| |
Volume |
10 |
Issue |
10 |
Pages |
239-243 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the design of nanosystems based on functionalized -Fe 2 O 3 nanostructures supported on fluorine-doped tin oxide (FTO) substrates. The target materials were developed by means of hybrid vapor phase approaches, combining plasma assisted-chemical vapor deposition (PA-CVD) for the production of iron(III) oxide systems and the subsequent radio frequency (RF)-sputtering or atomic layer deposition (ALD) for the functionalization with Au nanoparticles or TiO 2 overlayers, respectively. The interplay between material characteristics and the adopted processing parameters was investigated by complementary analytical techniques, encompassing X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), and energy dispersive X-ray spectroscopy (EDXS). The obtained results highlight the possibility of fabricating Au/ -Fe 2 O 3 nanocomposites, with a controlled dispersion and distribution of metal particles, and TiO 2 / -Fe 2 O 3 heterostructures, characterized by an intimate coupling between the constituent oxides. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2015-12-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2156-7573 |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
The authors acknowledge the financial support under the FP7 project “SOLARO- GENIX” (NMP4-SL-2012-310333), as well as Padova University ex-60% 2012–2015 projects, grant n CPDR132937/13 (SOLLEONE), and Regione Lombardia- INSTM ATLANTE program. Stuart Turner acknowledges the FWO Flanders for a post-doctoral scholarship. Thanks are also due to Dr. L. Borgese and Prof. E. Bontempi (Chemistry for Technologies Laboratory, Brescia Univer- sity, Italy) for precious assistance in ALD experiments. |
Approved |
Most recent IF: NA |
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| |
Call Number |
EMAT @ emat @ c:irua:132798 |
Serial |
4058 |
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Author |
Ranjbar, S.; Hadipour, A.; Vermang, B.; Batuk, M.; Hadermann, J.; Garud, S.; Sahayaraj, S.; Meuris, M.; Brammertz, G.; da Cunha, A.F.; Poortmans, J. |
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Title |
P-N Junction Passivation in Kesterite Solar Cells by Use of Solution-Processed TiO2 Layer |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
IEEE journal of photovoltaics |
Abbreviated Journal |
Ieee J Photovolt |
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Volume |
7 |
Issue |
7 |
Pages |
1130-1135 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In this work, we used a solution-processed TiO2 layer between Cu2ZnSnSe4 and CdS buffer layer to reduce the recombination at the p–n junction. Introducing the TiO2 layer showed a positive impact on VOC but fill factor and efficiency decreased. Using a KCN treatment, we could create openings in the TiO2 layer, as confirmed by transmission electron microscopy measurements. Formation of these openings in the TiO2 layer led to the improvement of the short-circuit current, fill factor, and the efficiency of the modified solar cells. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000404258900026 |
Publication Date |
2017-04-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2156-3381 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.712 |
Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
This work was supported in part by the European Union’s Horizon 2020 research and innovation program under Grant 640868, in part by the Flemish government, Department Economy, Science and Innovation, in part by the FEDER funds through the COMPETE 2020 Programme, and in part by the National Funds through FCT – Portuguese Foundation for Science and Technology under the project UID/CTM/50025/2013. The work of S. Ranjbar was supported by the Portuguese Science and Technology Foundation through Ph.D. grant SFRH/BD/78409/2011. The work of B. Vermang was supported by the Flemish Research Foundation FWO (mandate 12O4215N). |
Approved |
Most recent IF: 3.712 |
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| |
Call Number |
EMAT @ emat @ c:irua:143986 |
Serial |
4583 |
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| Permanent link to this record |
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Author |
Ennaert, T.; Geboers, J.; Gobechiya, E.; Courtin, C.M.; Kurttepeli, M.; Houthoofd, K.; Kirschhock, C.E.A.; Magusin, P.C.M.M.; Bals, S.; Jacobs, P.A.; Sels, B.F. |
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Title |
Conceptual frame rationalizing the self-stabilization of H-USY zeolites in hot liquid water |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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| |
Volume |
5 |
Issue |
5 |
Pages |
754-768 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The wide range of liquid-phase reactions required for the catalytic conversion of biomass compounds into new bioplatform molecules defines a new set of challenges for the development of active, selective, and stable catalysts. The potential of bifunctional Ru/H-USY catalysts for conversions in hot liquid water (HLW) is assessed in terms of physicochemical stability and long-term catalytic performance of acid sites and noble metal functionality, as probed by hydrolytic hydrogenation of cellulose. It is shown that zeolite desilication is the main zeolite degradation mechanism in HLW. USY zeolite stability depends on two main parameters, viz., framework and extra-framework aluminum content. The former protects the zeolite lattice by counteracting hydrolysis of framework bonds, and the latter, when located at the external crystal surface, prevents solubilization of the zeolite framework which is the result of its low water-solubility. Hence, the hot liquid water stability of commercial H-USY zeolites, in contrast to their steam stability, increased with decreasing Si/AI ratio. As a result, mildly steamed USY zeolites containing a high amount of both Al species exhibit the highest resistance to HLW. During an initial period of transformations, Al-rich zeolites form additional protective extra-framework Al species at the outer surface, self-stabilizing the framework. A critical bulk Si/AI ratio of 3 was determined whereby USY zeolites with a lower Si/AI ratio will self-stabilize over time. Besides, due to the initial transformation period, the accessibility of the catalytic active sites is extensively enhanced resulting in a material that is more stable and drastically more accessible to large substrates than the original zeolite. When these findings are applied in the hydrolytic hydrogenation of cellulose, unprecedented nearly quantitative hexitol yields were obtained with a stable catalytic system. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000349275300031 |
Publication Date |
2014-12-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2155-5435;2155-5435; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
10.614 |
Times cited |
65 |
Open Access |
OpenAccess |
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| |
Notes |
335078 Colouratom; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 10.614; 2015 IF: 9.312 |
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| |
Call Number |
c:irua:125288 |
Serial |
474 |
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| Permanent link to this record |
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Author |
Mei, B.; Wiktor, C.; Turner, S.; Pougin, A.; Van Tendeloo, G.; Fischer, R.A.; Muhler, M.; Strunk, J. |
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Title |
Evidence for metalsupport interactions in Au modified TiOx/SBA-15 materials prepared by photodeposition |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
3 |
Issue |
12 |
Pages |
3041-3049 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Gold nanoparticles have been efficiently photodeposited onto titanate-loaded SBA-15 (Ti(x)/SBA-15) with different titania coordination. Transmission electron microscopy shows that relatively large Au nanoparticles are photodeposited on the outer surface of the Ti(x)/SBA-15 materials and that TiOx tends to form agglomerates in close proximity to the Au nanoparticles, often forming coreshell Au/TiOx structures. This behavior resembles typical processes observed due to strong-metal support interactions. In the presence of gold, the formation of hydrogen on Ti(x)/SBA-15 during the photodeposition process and the performance in the hydroxylation of terephthalic acid is greatly enhanced. The activity of the Au/Ti(x)/SBA-15 materials is found to depend on the TiOx loading, increasing with a larger amount of initially isolated TiO4 tetrahedra. Samples with initially clustered TiOx species show lower photocatalytic activities. When isolated zinc oxide (ZnOx) species are present on Ti(x)/SBA-15, gold nanoparticles are smaller and well dispersed within the pores. Agglomeration of TiOx species and the formation of Au/TiOx structures is negligible. The dispersion of gold and the formation of Au/TiOx in the SBA-15 matrix seem to depend on the mobility of the TiOx species. The mobility is determined by the initial degree of agglomeration of TiOx. Effective hydrogen evolution requires Au/TiOx coreshell composites as in Au/Ti(x)/SBA-15, whereas hydroxylation of terephthalic acid can also be performed with Au/ZnOx/TiOx/SBA-15 materials. However, isolated TiOx species have to be grafted onto the support prior to the zinc oxide species, providing strong evidence for the necessity of TiOSi bridges for high photocatalytic activity in terephthalic acid hydroxylation. |
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Wos |
000328231400044 |
Publication Date |
2013-11-05 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435;2155-5435; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
22 |
Open Access |
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Notes |
262348 ESMI; FWO; 246791 COUNTATOMS; IAP-PAI; Hercules |
Approved |
Most recent IF: 10.614; 2013 IF: 7.572 |
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Call Number |
UA @ lucian @ c:irua:112502 |
Serial |
1094 |
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Author |
Geboes, B.; Ustarroz, J.; Sentosun, K.; Vanrompay, H.; Hubin, A.; Bals, S.; Breugelmans, T. |
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Title |
Electrochemical behavior of electrodeposited nanoporous Pt catalysts for the oxygen reduction reaction |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
6 |
Issue |
6 |
Pages |
5856-5864 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
Nanoporous Pt based nanoparticles (NP's) are promising fuel cell catalysts due to their high surface area and increased electrocatalytic activity toward the ORR In this work a direct double-pulse electrodeposition procedure at room temperature is applied to obtain dendritic Pt structures (89 nm diameter) with a high level of porosity (ca. 25%) and nanopores of 2 nm protruding until the center of the NP's. The particle morphology is characterized using aberration corrected high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and electron tomography (ET) combined with field emission scanning electron microscopy (FESEM) and macroscopic electrochemical measurements to assess their activity and stability toward the ORR. Macroscopic determination of the active surface area through hydrogen UPD measurements in combination with FESEM and ET showed that a considerable amount of the active sites inside the pores of the low overpotential NP's were accessible to oxygen species. As a result of this accessibility, up to a 9-fold enhancement of the Pt mass corrected ORR activity at 0.85 V vs RHE was observed at the highly porous structures. After successive potential cycling upward to 1.5 V vs RHE in a deaerated HClO4 solution a negative shift of 71 mV in half-wave potential occurred. This decrease in ORR activity could be correlated to the partial collapse of the nanopores, visible in both the EASA values and 3D ET reconstructions. |
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Wos |
000382714000025 |
Publication Date |
2016-07-18 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
48 |
Open Access |
OpenAccess |
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Notes |
; The Quanta 250 FEG microscope of the Electron Microscopy for Material Science group at the University of Antwerp was funded by the Hercules foundation of the Flemish Government. The authors acknowledge financial support from the Fonds Wetenschappelijk Onderzoek in Flanders (FWOAL708). S.B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). J.U. acknowledges funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, postdoctoral grant 12I7816N). ; ecas_Sara |
Approved |
Most recent IF: 10.614 |
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Call Number |
UA @ lucian @ c:irua:135703 |
Serial |
4302 |
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| Permanent link to this record |
