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Author |
M. K. Kinyanjui, N. Gauquelin, E. Benckiser, H. –U. Habermeier, B. Keimer, U. Kaiser and G.A. Botton |
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Title |
Local lattice distortion and anisotropic modulation in Epitaxially Strained LaNiO3/LaAlO3 hetero-structures |
Type |
A1 Journal Article |
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Year |
2014 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
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Volume |
104 |
Issue |
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Pages |
221909 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Using a complementary combination of x-ray diffraction and atomically resolved imaging we investigated the lattice structure of epitaxial LaNiO3/LaAlO3 superlattices grown on a compressive-strain inducing LaSrAlO4 (001) substrate. A refinement of the structure obtained from the x-ray data revealed the monoclinic I 2/c 1 1 space group. The (Ni/Al)O6 octahedral rotation angle perpendicular to the superlattice plane is enhanced, and the one parallel to the plane is reduced with respect to the corresponding bulk values. High-angle annular dark field imaging was used to determine the lattice parameters within the superlattice unit cell. High-resolution electron microscopy images of the oxygen atoms are consistent with the x-ray results. |
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Wos |
000337161700029 |
Publication Date |
2014-06-07 |
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Times cited |
22 |
Open Access |
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Most recent IF: NA |
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Call Number  |
EMAT @ emat @ |
Serial |
4545 |
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Author |
H. Zhang, N. Gauquelin, G.A. Botton and J.Y.T. Wei |
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Title |
Attenuation of superconductivity in manganite/cuprate heterostructures by epitaxially induced CuO intergrowths |
Type |
A1 Journal Article |
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Year |
2013 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
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Volume |
103 |
Issue |
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Pages |
052606 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
We examine the effect of CuO intergrowths on the superconductivity in epitaxial
La 2/3 Ca 1/3 MnO 3 / YBa 2 Cu 3 O 7−δ La2/3Ca1/3MnO3/YBa2Cu3O7−δ
(LCMO/YBCO) thin-film heterostructures. Scanning transmission electron microscopy on bilayer LCMO/YBCO thin films revealed double CuO-chain intergrowths which form regions with the 247 lattice structure in the YBCO layer. These nanoscale 247 regions do not appear in x-ray diffraction, but can physically account for the reduced critical temperature (Tc) of bilayer thin films relative to unilayer films with the same YBCO thickness, at least down to ∼25 nm. We attribute the CuO intergrowths to the bilayer heteroepitaxial mismatch and the Tc reduction to the generally lower Tc seen in bulk 247 samples. These epitaxially-induced CuO intergrowths provide a microstructural mechanism for the attenuation of superconductivity in LCMO/YBCO heterostructures. |
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Wos |
000322723000063 |
Publication Date |
2013-08-02 |
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Times cited |
12 |
Open Access |
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Most recent IF: NA |
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Call Number |
EMAT @ emat @ |
Serial |
4546 |
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Author |
L. Zhang, J. Kim, J. Zhang, F. Nan, N. Gauquelin, G.A. Botton, P. He, R. Bashyam, S. Knights |
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Title |
Ti4O7 supported Ru@Pt core–shell catalyst for CO-tolerance in PEM fuel cell hydrogen oxidation reaction |
Type |
A1 Journal Article |
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Year |
2013 |
Publication |
Applied Energy |
Abbreviated Journal |
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Volume |
103 |
Issue |
March 2013 |
Pages |
507-513 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
A new method is developed for synthesizing Ti4O7 supported Ru@Pt core–shell catalyst (Ru@Pt/Ti4O7) through pyrolysis followed by microwave irradiation. The purpose is to improve the Ru durability of PtRu from core–shell structure and strong bonding to Ti4O7 oxide. In this method, the first step is to co-reduce the mixture of ruthenium precursor and TiO2 in a H2 reducing atmosphere under heat-treatment to obtain a Ru core on Ti4O7 support, and the second step is to create a shell of platinum via microwave irradiation. Energy dispersive X-ray spectrometry, X-ray Diffraction, High-resolution Scanning Transmission Electron Microscopy with the high-angle annular dark-field method and Electron Energy-Loss Spectroscopy are used to demonstrate that this catalyst with larger particles has a core–shell structure with a Ru core and a Pt shell. Electrochemical measurements show Ru@Pt/Ti4O7 catalyst has a higher CO-tolerance capability than that of PtRu/C alloy catalyst. |
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Wos |
000314669500048 |
Publication Date |
2012-11-11 |
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Impact Factor |
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Times cited |
33 |
Open Access |
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Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @ |
Serial |
4547 |
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Author |
Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M. |
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Title |
Cobalt location in p -CoO x / n -SnO 2 nanocomposites: Correlation with gas sensor performances |
Type |
A1 Journal Article |
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Year |
2017 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
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Volume |
721 |
Issue |
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Pages |
249-260 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction. |
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Wos |
000405252400030 |
Publication Date |
2017-06-02 |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
0925-8388 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.133 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
This work was supported by ERA-Net.Plus grant N 096 FONSENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University. |
Approved |
Most recent IF: 3.133 |
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Call Number |
EMAT @ emat @ |
Serial |
4711 |
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Author |
van der Torren, A.J.H.; Liao, Z.; Xu, C.; Gauquelin, N.; Yin, C.; Aarts, J.; van der Molen, S.J. |
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Title |
Formation of a conducting LaAlO3/SrTiO3 interface studied by low-energy electron reflection during growth |
Type |
A1 Journal Article |
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Year |
2017 |
Publication |
Physical Review Materials |
Abbreviated Journal |
Phys. Rev. Materials |
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Volume |
1 |
Issue |
7 |
Pages |
075001 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
The two-dimensional electron gas occurring between the band insulators SrTiO 3 and LaAlO 3 continues to attract considerable interest, due to the possibility of dynamic control over the carrier density, and the ensuing phenomena such as magnetism and superconductivity. The formation of this conducting interface is sensitive to the growth conditions, but despite numerous investigations, there are still questions about the details of the physics involved. In particular, not much is known about the electronic structure of the growing LaAlO 3 layer at the growth temperature (around 800 ◦ C) in oxygen (pressure around 5 × 10 −5 mbar), since analysis techniques at these conditions are not readily available. We developed a pulsed laser deposition system inside a low-energy electron microscope in order to study this issue. The setup allows for layer-by-layer growth control and in-situ measurements of the angle-dependent electron reflection intensity, which can be used as a fingerprint of the electronic structure of the surface layers during growth. By using different substrate terminations and growth conditions we observe two families of reflectivity maps, which we can connect either to samples with an AlO 2 -rich surface and a conducting interface; or to samples with a LaO-rich surface and an insulating interface. Our observations emphasize that substrate termination and stoichiometry determine the electronic structure of the growing layer, and thereby the conductance of the interface. |
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Wos |
000418770200003 |
Publication Date |
2017-12-06 |
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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 |
2475-9953 |
ISBN |
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Additional Links |
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Impact Factor |
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Times cited |
2 |
Open Access |
Not_Open_Access |
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Notes |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Fonds Wetenschappelijk Onderzoek, G.0044.13N ; European Cooperation in Science and Technology, MP 1308 ; We want to acknowledge Ruud Tromp, Daniel Gee- len, Johannes Jobst, Regina Dittmann, Gert Jan Koster, Guus Rijnders and Jo Verbeek for discussions and ad- vice and Ruud van Egmond and Marcel Hesselberth for technical assistance. This work was supported by the Netherlands Organization for Scientific Research (NWO) by means of an ”NWO Groot” grant and by the Leiden- Delft Consortium NanoFront. The work is part of the re- search programmes NWOnano and DESCO, which are fi- nanced by NWO. N.G. acknowledges funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge order- ing). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. We would also like to acknowledge networking support by the COST Action MP 1308 (COST TO-BE). |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @ |
Serial |
4903 |
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Author |
Gasparotto, A.; Maccato, C.; Carraro, G.; Sada, C.; Štangar, U.L.; Alessi, B.; Rocks, C.; Mariotti, D.; La Porta, A.; Altantzis, T.; Barreca, D. |
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Title |
Surface Functionalization of Grown-on-Tip ZnO Nanopyramids: From Fabrication to Light-Triggered Applications |
Type |
A1 Journal Article |
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Year |
2019 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
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Volume |
11 |
Issue |
17 |
Pages |
15881-15890 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
We report on a combined chemical vapor deposition (CVD)/radio frequency (RF) sputtering synthetic strategy for the controlled surface modification of ZnO nanostructures by Ti-containing species. Specifically, the proposed approach consists in the CVD of grown-on-tip ZnO nanopyramids, followed by titanium RF sputtering under mild conditions. The results obtained by a thorough characterization demonstrate the successful ZnO surface functionalization with dispersed Ti-containing species in low amounts. This phenomenon, in turn, yields a remarkable enhancement of photoactivated superhydrophilic behavior, self-cleaning ability, and photocatalytic performances in comparison to bare ZnO. The reasons accounting for such an improvement are unravelled by a multitechnique analysis, elucidating the interplay between material chemico-physical properties and the corresponding functional behavior. Overall, the proposed strategy stands as an amenable tool for the mastering of semiconductor-based functional nanoarchitectures through ad hoc engineering of the system surface. |
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Wos |
000466988800078 |
Publication Date |
2019-04-18 |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
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Impact Factor |
7.504 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
The research leading to these results has received financial support from Padova University ACTION postdoc fellowship, DOR 2016-2018, P-DiSC #03BIRD2016-UNIPD projects, and HERALD COST Action MP1402-37831. The support from EPSRC (awards EP/R008841/1 and EP/M024938/1) as well as from the Slovenian Research Agency (research core funding No. P1-0134) is also recognized. T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). The authors are grateful to Dr. Sebastiano Pianta (Department of Chemical Sciences, Padova University, Italy) for experimental assistance. |
Approved |
Most recent IF: 7.504 |
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Call Number |
EMAT @ emat @ |
Serial |
5185 |
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Author |
Gasparotto, A.; Maccato, C.; Sada, C.; Carraro, G.; Kondarides, D.I.; Bebelis, S.; Petala, A.; La Porta, A.; Altantzis, T.; Barreca, D. |
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Title |
Controlled Surface Modification of ZnO Nanostructures with Amorphous TiO2for Photoelectrochemical Water Splitting |
Type |
A1 Journal Article |
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Year |
2019 |
Publication |
Advanced Sustainable Systems |
Abbreviated Journal |
Adv. Sustainable Syst. |
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Volume |
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Issue |
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Pages |
1900046 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
The utilization of solar radiation to trigger photoelectrochemical (PEC) water splitting has gained interest for sustainable energy production. In this study, attention is focused on the development of ZnO–TiO2 nanocomposite photoanodes. The target systems are obtained by growing porous arrays of highly crystalline, elongated ZnO nanostructures on indium tin oxide (ITO) by chemical vapor deposition. Subsequently, the obtained nanodeposits are functionalized with TiO2 via radio frequency-sputtering for different process durations, and subjected to final annealing in air. Characterization results demonstrate the successful formation of high purity composite systems in which the surface of ZnO nanostructures is decorated by ultra-small amounts of amorphous titania, whose content can be conveniently tailored as a function of deposition time. Photocurrent density measurements in sunlight triggered water splitting highlight a remarkable performance enhancement with respect to single-phase zinc and titanium oxides, with up to a threefold photocurrent increase compared to bare ZnO. These results, mainly traced back to the formation of ZnO/TiO2 heterojunctions yielding an improved photocarrier separation, show that the target nanocomposites are attractive photoanodes for efficient PEC water splitting. |
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Wos |
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Publication Date |
2019-06-03 |
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Edition |
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ISSN |
2366-7486 |
ISBN |
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Additional Links |
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Impact Factor |
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Times cited |
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Open Access |
Not_Open_Access |
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Notes |
This work was financially supported by Padova University DOR 2016–2019, P-DiSC #03BIRD2016-UNIPD, and #03BIRD2018-UNIPD projects and ACTION post-doc fellowship. A.G. acknowledges AMGAFoundation and INSTM Consortium. T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). Thanks are also due to Dr. Sebastiano Pianta (Department of Chemical Sciences, Padova University, Italy) for experimental assistance. |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @ |
Serial |
5186 |
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Author |
Bouwmeester, R.L.; de Hond, K.; Gauquelin, N.; Verbeeck, J.; Koster, G.; Brinkman, A. |
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Title |
Stabilization of the Perovskite Phase in the Y-Bi-O System By Using a BaBiO3 Buffer Layer |
Type |
A1 Journal Article |
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Year |
2019 |
Publication |
Physica Status Solidi-Rapid Research Letters |
Abbreviated Journal |
Phys Status Solidi-R |
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Volume |
13 |
Issue |
7 |
Pages |
1970028 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
A topological insulating phase has theoretically been predicted for the thermodynamically unstable perovskite phase of YBiO3. Here, it is shown that the crystal structure of the Y-Bi-O system can be controlled by using a BaBiO3 buffer layer. The BaBiO3 film overcomes the large lattice mismatch with the SrTiO3 substrate by forming a rocksalt structure in between the two perovskite structures. Depositing an YBiO3 film directly on a SrTiO3 substrate gives a fluorite structure. However, when the Y–Bi–O system is deposited on top of the buffer layer with the correct crystal phase and comparable lattice constant, a single oriented perovskite structure with the expected lattice constants is observed. |
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Wos |
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Publication Date |
2019-07-27 |
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Abbreviated Series Title |
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Edition |
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ISSN |
1862-6254 |
ISBN |
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Additional Links |
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Impact Factor |
3.032 |
Times cited |
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Open Access |
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Notes |
The work at the University of Twente is financially supported by NWO through a VICI grant. N.G. and J.V. acknowledge financial support from the GOA project Solarpaint of the University of Antwerp. The microscope used for this experiment has been partially financed by the Hercules Fund from the Flemish Government. L. Ding is acknowledge for his help with the GPA analysis. |
Approved |
Most recent IF: 3.032 |
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Call Number |
EMAT @ emat @ |
Serial |
5358 |
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Author |
Pramanik, G.; Kvakova, K.; Thottappali, M.A.; Rais, D.; Pfleger, J.; Greben, M.; El-Zoka, A.; Bals, S.; Dracinsky, M.; Valenta, J.; Cigler, P. |
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Title |
Inverse heavy-atom effect in near infrared photoluminescent gold nanoclusters |
Type |
A1 Journal Article |
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Year |
2021 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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Volume |
13 |
Issue |
23 |
Pages |
10462-10467 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Fluorophores functionalized with heavy elements show enhanced intersystem crossing due to increased spin–orbit coupling, which in turn shortens the fluorescence decay lifetime (<italic>τ</italic><sup>PL</sup>). This phenomenon is known as the heavy-atom effect (HAE). Here, we report the observation of increased<italic>τ</italic><sup>PL</sup>upon functionalisation of near-infrared photoluminescent gold nanoclusters with iodine. The heavy atom-mediated increase in<italic>τ</italic><sup>PL</sup>is in striking contrast with the HAE and referred to as inverse HAE. Femtosecond and nanosecond transient absorption spectroscopy revealed overcompensation of a slight decrease in lifetime of the transition associated with the Au core (ps) by a large increase in the long-lived triplet state lifetime associated with the Au shell, which contributed to the observed inverse HAE. This unique observation of inverse HAE in gold nanoclusters provides the means to enhance the triplet excited state lifetime. |
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Wos |
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Publication Date |
2021-05-24 |
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Series Issue |
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Edition |
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ISSN |
2040-3364 |
ISBN |
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Impact Factor |
7.367 |
Times cited |
7 |
Open Access |
OpenAccess |
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Notes |
The authors acknowledge support from GACR project Nr.18- 12533S. G. P. acknowledges support from EUSMI project No. E180200060; J.P. from the Ministry of Education, Youth and Sports of the Czech Republic – Program INTER-EXCELLENCE (LTAUSA19066). |
Approved |
Most recent IF: 7.367 |
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Call Number |
EMAT @ emat @ |
Serial |
6950 |
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Author |
Vlasov, E.; Heyvaert, W.; Ni, B.; Van Gordon, K.; Girod, R.; Verbeeck, J.; Liz-Marzán, L.M.; Bals, S. |
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Title |
High-Throughput Morphological Chirality Quantification of Twisted and Wrinkled Gold Nanorods |
Type |
A1 Journal Article |
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Year |
2024 |
Publication |
ACS Nano |
Abbreviated Journal |
ACS Nano |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Chirality in gold nanostructures offers an exciting opportunity to tune their differential optical response to left- and right-handed circularly polarized light, as well as their interactions with biomolecules and living matter. However, tuning and understanding such interactions demands quantification of the structural features that are responsible for the chiral behavior. Electron tomography (ET) enables structural characterization at the single-particle level and has been used to quantify the helicity of complex chiral nanorods. However, the technique is time-consuming and consequently lacks statistical value. To address this issue, we introduce herein a high-throughput methodology that combines images acquired by secondary electron-based electron beam-induced current (SEEBIC) with quantitative image analysis. As a result, the geometric chirality of hundreds of nanoparticles can be quantified in less than 1 h. When combining the drastic gain in data collection efficiency of SEEBIC with a limited number of ET data sets, a better understanding of how the chiral structure of individual chiral nanoparticles translates into the ensemble chiroptical response can be reached. |
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Wos |
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Publication Date |
2024-04-26 |
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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 |
1936-0851 |
ISBN |
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Additional Links |
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Impact Factor |
17.1 |
Times cited |
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Open Access |
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Notes |
The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.) and from MCIN/AEI/10.13039/501100011033 (Grant PID2020-117779RB-I00 to L.M.L.-M and FPI Fellowship PRE2021-097588 to K.V.G.). Funded by the European Union under Project 101131111 − DELIGHT, JV acknowledges the eBEAM project supported by the European Union’s Horizon 2020 research and innovation program FETPROACT-EIC-07- 2020: emerging paradigms and communities. |
Approved |
Most recent IF: 17.1; 2024 IF: 13.942 |
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Call Number |
EMAT @ emat @ |
Serial |
9121 |
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| Permanent link to this record |
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Author |
Guerrero, R.M.; Lemir, I.D.; Carrasco, S.; Fernández-Ruiz, C.; Kavak, S.; Pizarro, P.; Serrano, D.P.; Bals, S.; Horcajada, P.; Pérez, Y. |
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Title |
Scaling-Up Microwave-Assisted Synthesis of Highly Defective Pd@UiO-66-NH2Catalysts for Selective Olefin Hydrogenation under Ambient Conditions |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
ACS Applied Materials & Interfaces |
Abbreviated Journal |
ACS Appl. Mater. Interfaces |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
The need to develop green and cost-effective industrial catalytic processes has led to growing interest in preparing more robust, efficient, and selective heterogeneous catalysts at a large scale. In this regard, microwave-assisted synthesis is a fast method for fabricating heterogeneous catalysts (including metal oxides, zeolites, metal–organic frameworks, and supported metal nanoparticles) with enhanced catalytic properties, enabling synthesis scale-up. Herein, the synthesis of nanosized UiO-66-NH2 was optimized via a microwave-assisted hydrothermal method to obtain defective matrices essential for the stabilization of metal nanoparticles, promoting catalytically active sites for hydrogenation reactions (760 kg·m–3·day–1 space time yield, STY). Then, this protocol was scaled up in a multimodal microwave reactor, reaching 86% yield (ca. 1 g, 1450 kg·m–3·day–1 STY) in only 30 min. Afterward, Pd nanoparticles were formed in situ decorating the nanoMOF by an effective and fast microwave-assisted hydrothermal method, resulting in the formation of Pd@UiO-66-NH2 composites. Both the localization and oxidation states of Pd nanoparticles (NPs) in the MOF were achieved using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray photoelectron spectroscopy (XPS), respectively. The optimal composite, loaded with 1.7 wt % Pd, exhibited an extraordinary catalytic activity (>95% yield, 100% selectivity) under mild conditions (1 bar H2, 25 °C, 1 h reaction time), not only in the selective hydrogenation of a variety of single alkenes (1-hexene, 1-octene, 1-tridecene, cyclohexene, and tetraphenyl ethylene) but also in the conversion of a complex mixture of alkenes (i.e., 1-hexene, 1-tridecene, and anethole). The results showed a powerful interaction and synergy between the active phase (Pd NPs) and the catalytic porous scaffold (UiO-66-NH2), which are essential for the selectivity and recyclability. |
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Place of Publication |
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Wos |
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Publication Date |
2024-04-26 |
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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 |
1944-8244 |
ISBN |
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Additional Links |
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| |
Impact Factor |
9.5 |
Times cited |
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Open Access |
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| |
Notes |
The authors gratefully acknowledge financial support from “Comunidad de Madrid” and European Regional Development Fund-FEDER through the project HUB MADRID+CIRCULAR; the State Research Agency (MCIN/AEI /10.13039/501100011033) through the grant with reference number CEX2019-000931-M received in the 2019 call for “Severo Ochoa Centres of Excellence” and “María de Maeztu Units of Excellence” of the State Programme for Knowledge Generation and Scientific and Technological Strengthening of the R&D&I System; and MICIU through the project “NAPOLION” (PID2022-139956OB-I00). S.K. acknowledges the Flemish Fund for Scientific Research (FWO Vlaanderen) through a PhD research grant (1181124N). |
Approved |
Most recent IF: 9.5; 2024 IF: 7.504 |
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Call Number |
EMAT @ emat @ |
Serial |
9126 |
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| Permanent link to this record |
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Author |
Van Gordon, K.; Ni, B.; Girod, R.; Mychinko, M.; Bevilacqua, F.; Bals, S.; Liz‐Marzán, L.M. |
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Title |
Single Crystal and Pentatwinned Gold Nanorods Result in Chiral Nanocrystals with Reverse Handedness |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Angewandte Chemie International Edition |
Abbreviated Journal |
Angew Chem Int Ed |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Handedness is an essential attribute of chiral nanocrystals, having a major influence on their properties. During chemical growth, the handedness of nanocrystals is usually tuned by selecting the corresponding enantiomer of chiral molecules involved in asymmetric growth, often known as chiral inducers. We report that, even using the same chiral inducer enantiomer, the handedness of chiral gold nanocrystals can be reversed by using Au nanorod seeds with either single crystalline or pentatwinned structure. This effect holds for chiral growth induced both by amino acids and by chiral micelles. Although it was challenging to discern the morphological handedness for<italic>L</italic>‐cystine‐directed particles, even using electron tomography, both cases showed circular dichroism bands of opposite sign, with nearly mirrored chiroptical signatures for chiral micelle‐directed growth, along with quasi‐helical wrinkles of inverted handedness. These results expand the chiral growth toolbox with an effect that might be exploited to yield a host of interesting morphologies with tunable optical properties. |
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Place of Publication |
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Wos |
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Publication Date |
2024-05-24 |
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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 |
1433-7851 |
ISBN |
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Additional Links |
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Impact Factor |
16.6 |
Times cited |
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Open Access |
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Notes |
Ana Sánchez-Iglesias is acknowledged for support in the synthesis of pentatwinned gold nanorods. The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.), from MCIN/AEI/10.13039/501100011033 (Grant PID2020- 117779RB-I00 to L.M.L.-M and FPI Fellowship PRE2021- 097588 to K.V.G.), and by KU Leuven (C14/22/085). This work has been funded by the European Union under Project 101131111—DELIGHT. Funding for open access charge: Universidade de Vigo/ CRUE-CISUG. |
Approved |
Most recent IF: 16.6; 2024 IF: 11.994 |
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Call Number |
EMAT @ emat @ |
Serial |
9129 |
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| Permanent link to this record |
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Author |
Borah, R.; Verbruggen, S.W. |
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Title |
Effect of size distribution, skewness and roughness on the optical properties of colloidal plasmonic nanoparticles |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Colloids and surfaces: A: physicochemical and engineering aspects |
Abbreviated Journal |
Colloid Surface A |
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Volume |
640 |
Issue |
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Pages |
128521 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
It is a generally accepted idea that the particle size distribution strongly affects the optical spectra of colloidal plasmonic nanoparticles. It is often quoted as one of the main reasons while explaining the mismatch between the theoretical and experimental optical spectra of such nanoparticles. In this work, these aspects are critically analyzed by means of a bottom up statistical approach that considers variables such as mean, standard deviation and skewness of the nanoparticle size distribution independently from one another. By assuming normal and log-normal distributions of the particle size, the effect of the statistical parameters on the Mie analytical optical spectra of colloidal nanoparticles was studied. The effect of morphology was also studied numerically in order to understand to what extent it can play a role. It is our finding that the particle polydispersity, skewness and surface morphology in fact only weakly impact the optical spectra. While, the selection of suitable optical constants with regard to the crystallinity of the nanoparticles is a far more influential factor for correctly predicting both the plasmon band position and the plasmon bandwidth in theoretical simulations of the optical spectra. It is shown that the mean particle size can be correctly estimated directly from the plasmon band position, as it is the mean that determines the resonance wavelength. The standard deviation can on the other hand be estimated from the intensity distribution data obtained from dynamic light scattering experiments. The results reported herein clear the ambiguity around particle size distribution and optical response of colloidal plasmonic nanoparticles. |
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Thesis |
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Publisher |
Elservier |
Place of Publication |
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Editor |
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Language |
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Wos |
000765946900002 |
Publication Date |
2022-02-04 |
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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 |
0927-7757 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.2 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 5.2 |
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Call Number |
DuEL @ duel @c:irua:185704 |
Serial |
6908 |
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| Permanent link to this record |
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Author |
Borah, R.; Verbruggen, S.W. |
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Title |
Silver–Gold Bimetallic Alloy versus Core–Shell Nanoparticles: Implications for Plasmonic Enhancement and Photothermal Applications |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
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Volume |
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Issue |
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Pages |
acs.jpcc.0c02630 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Bimetallic plasmonic nanoparticles enable tuning of the optical response and chemical stability by variation of the composition. The present numerical simulation study compares Ag–Au alloy, Ag@Au core–shell, and Au@Ag core–shell bimetallic plasmonic nanoparticles of both spherical and anisotropic (nanotriangle and nanorods) shapes. By studying both spherical and anisotropic (with LSPR in the near-infrared region) shapes, cases with and without interband transitions of Au can be decoupled. Explicit comparisons are facilitated by numerical models supported by careful validation and examination of optical constants of Au–Ag alloys reported in the literature. Although both Au–Ag core–shell and alloy nanoparticles exhibit an intermediary optical response between that of pure Ag and Au nanoparticles, there are noticeable differences in the spectral characteristics. Also, the effect of the bimetallic constitution in anisotropic nanoparticles is starkly different from that in spherical nanoparticles due to the absence of Au interband transitions in the former case. In general, the improved chemical stability of Ag nanoparticles by incorporation of Au comes with a cost of reduction in plasmonic enhancement, also applicable to anisotropic nanoparticles with a weaker effect. A photothermal heat transfer study confirms that increased absorption by the incorporation of Au in spherical Ag nanoparticles also results in an increased steady-state temperature. On the other hand, anisotropic nanoparticles are inherently better absorbers and hence better photothermal sources, and their photothermal properties are apparently not strongly affected by the incorporation of one metal in the other. This study of the optical/spectral and photothermal characteristics of bimetallic Au–Ag alloy versus core–shell nanoparticles provides detailed physical insight for development of new taylor-made plasmonic nanostructures. |
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Corporate Author |
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Place of Publication |
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Wos |
000538758700039 |
Publication Date |
2020-05-19 |
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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 |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
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Open Access |
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Notes |
Universiteit Antwerpen, DOCPRO4 Rituraj Borah ; |
Approved |
Most recent IF: 3.7; 2020 IF: 4.536 |
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Call Number |
DuEL @ duel @c:irua:169223 |
Serial |
6367 |
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| Permanent link to this record |
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Author |
Borah, R.; Verbruggen, S.W. |
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Title |
Silver–Gold Bimetallic Alloy versus Core–Shell Nanoparticles: Implications for Plasmonic Enhancement and Photothermal Applications |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
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Volume |
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Issue |
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Pages |
acs.jpcc.0c02630 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Bimetallic plasmonic nanoparticles enable tuning of the optical response and chemical stability by variation of the composition. The present numerical simulation study compares Ag–Au alloy, Ag@Au core–shell, and Au@Ag core–shell bimetallic plasmonic nanoparticles of both spherical and anisotropic (nanotriangle and nanorods) shapes. By studying both spherical and anisotropic (with LSPR in the near-infrared region) shapes, cases with and without interband transitions of Au can be decoupled. Explicit comparisons are facilitated by numerical models supported by careful validation and examination of optical constants of Au–Ag alloys reported in the literature. Although both Au–Ag core–shell and alloy nanoparticles exhibit an intermediary optical response between that of pure Ag and Au nanoparticles, there are noticeable differences in the spectral characteristics. Also, the effect of the bimetallic constitution in anisotropic nanoparticles is starkly different from that in spherical nanoparticles due to the absence of Au interband transitions in the former case. In general, the improved chemical stability of Ag nanoparticles by incorporation of Au comes with a cost of reduction in plasmonic enhancement, also applicable to anisotropic nanoparticles with a weaker effect. A photothermal heat transfer study confirms that increased absorption by the incorporation of Au in spherical Ag nanoparticles also results in an increased steady-state temperature. On the other hand, anisotropic nanoparticles are inherently better absorbers and hence better photothermal sources, and their photothermal properties are apparently not strongly affected by the incorporation of one metal in the other. This study of the optical/spectral and photothermal characteristics of bimetallic Au–Ag alloy versus core–shell nanoparticles provides detailed physical insight for development of new taylor-made plasmonic nanostructures. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
000538758700039 |
Publication Date |
2020-05-19 |
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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 |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
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Open Access |
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Notes |
Universiteit Antwerpen, DOCPRO4 Rituraj Borah ; |
Approved |
Most recent IF: 3.7; 2020 IF: 4.536 |
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Call Number |
DuEL @ duel @c:irua:169223 |
Serial |
6368 |
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Author |
Spanoghe, J.; Grunert, O.; Wambacq, E.; Sakarika, M.; Papini, G.; Alloul, A.; Spiller, M.; Derycke, V.; Stragier, L.; Verstraete, H.; Fauconnier, K.; Verstraete, W.; Haesaert, G.; Vlaeminck, S.E. |
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Title |
Storage, fertilization and cost properties highlight the potential of dried microbial biomass as organic fertilizer |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Microbial biotechnology |
Abbreviated Journal |
Microb. Biotechnol. |
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Volume |
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Issue |
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Pages |
1-13 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
The transition to sustainable agriculture and horticulture is a societal challenge of global importance. Fertilization with a minimum impact on the environment can facilitate this. Organic fertilizers can play an important role, given their typical release pattern and production through resource recovery. Microbial fertilizers (MFs) constitute an emerging class of organic fertilizers and consist of dried microbial biomass, for instance produced on effluents from the food and beverage industry. In this study, three groups of organisms were tested as MFs: a high-rate consortium aerobic bacteria (CAB), the microalga Arthrospira platensis (‘Spirulina’) and a purple non-sulfur bacterium (PNSB) Rhodobacter sp. During storage as dry products, the MFs showed light hygroscopic activity, but the mineral and organic fractions remained stable over a storage period of 91 days. For biological tests, a reference organic fertilizer (ROF) was used as positive control, and a commercial organic growing medium (GM) as substrate. The mineralization patterns without and with plants were similar for all MFs and ROF, with more than 70% of the organic nitrogen mineralized in 77 days. In a first fertilization trial with parsley, all MFs showed equal performance compared to ROF, and the plant fresh weight was even higher with CAB fertilization. CAB was subsequently used in a follow-up trial with petunia and resulted in elevated plant height, comparable chlorophyll content and a higher amount of flowers compared to ROF. Finally, a cost estimation for packed GM with supplemented fertilizer indicated that CAB and a blend of CAB/PNSB (85%/15%) were most cost competitive, with an increase of 6% and 7% in cost compared to ROF. In conclusion, as biobased fertilizers, MFs have the potential to contribute to sustainable plant nutrition, performing as good as a commercially available organic fertilizer, and to a circular economy. |
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Wos |
000563539700001 |
Publication Date |
2020-03-16 |
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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 |
1751-7915 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.7 |
Times cited |
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Open Access |
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Notes |
The authors would like to kindly acknowledge (i) the MIP i‐Cleantech Flanders (Milieu‐innovatieplatform; Environment innovation platform) project Microbial Nutrients on Demand (MicroNOD) for financial support, (ii) the DOCPRO4 project ‘PurpleTech’, funded by the BOF (Bijzonder onderzoeksfonds; Special research fund) from the University of Antwerp for financially supporting J.S., (iii) all MicroNOD partners, including the University of Antwerp, Ghent University, AgrAqua, Greenyard Horticulture and Avecom; and (iv) all steering committee members, including Greenyard Frozen, Agristo, AVBS, Vlakwa, het Innovatiesteunpunt, VCM and OVAM. |
Approved |
Most recent IF: 5.7; 2020 IF: NA |
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Call Number |
DuEL @ duel @c:irua:167595 |
Serial |
6357 |
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| Permanent link to this record |
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Author |
Kourmoulakis, G.; Michail, A.; Paradisanos, I.; Marie, X.; Glazov, M.M.; Jorissen, B.; Covaci, L.; Stratakis, E.; Papagelis, K.; Parthenios, J.; Kioseoglou, G. |
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Title |
Biaxial strain tuning of exciton energy and polarization in monolayer WS2 |
Type |
A1 Journal Article |
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Year |
2023 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
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Volume |
123 |
Issue |
22 |
Pages |
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Keywords |
A1 Journal Article; Condensed Matter Theory (CMT) ; |
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Abstract |
We perform micro-photoluminescence and Raman experiments to examine the impact of biaxial tensile strain on the optical properties of WS2 monolayers. A strong shift on the order of −130 meV per % of strain is observed in the neutral exciton emission at room temperature. Under near-resonant excitation, we measure a monotonic decrease in the circular polarization degree under the applied strain. We experimentally separate the effect of the strain-induced energy detuning and evaluate the pure effect coming from the biaxial strain. The analysis shows that the suppression of the circular polarization degree under the biaxial strain is related to an interplay of energy and polarization relaxation channels as well as to variations in the exciton oscillator strength affecting the long-range exchange interaction. |
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Wos |
001124156400003 |
Publication Date |
2023-11-27 |
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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 |
0003-6951 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4 |
Times cited |
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Open Access |
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Notes |
Hellenic Foundation for Research and Innovation, HFRI-FM17-3034 ; |
Approved |
Most recent IF: 4; 2023 IF: 3.411 |
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Call Number |
CMT @ cmt @c:irua:202178 |
Serial |
8991 |
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Author |
Claes, J.; Partoens, B.; Lamoen, D. |
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Title |
Decoupled DFT-1/2 method for defect excitation energies |
Type |
A1 Journal Article |
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Year |
2023 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys. Rev. B |
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Volume |
108 |
Issue |
12 |
Pages |
125306 |
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Keywords |
A1 Journal Article; Condensed Matter Theory (CMT) ; |
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Abstract |
The DFT-1/2 method is a band-gap correction with GW precision at a density functional theory (DFT) computational cost. The method was also extended to correct the gap between defect levels, allowing for the calculation of optical transitions. However, this method fails when the atomic character of the occupied and unoccupied defect levels is similar as we illustrate by two examples, the tetrahedral hydrogen interstitial and the negatively charged vacancy in diamond. We solve this problem by decoupling the effect of the occupied and unoccupied defect levels and call this the decoupled DFT-1/2 method for defects. |
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Wos |
001089302800003 |
Publication Date |
2023-09-25 |
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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 |
2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.7 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
This work was supported by the FWO (Research Foundation-Flanders), Project No. G0D1721N. This work was performed in part using HPC resources from the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government department EWI (Economie, Wetenschap & Innovatie). |
Approved |
Most recent IF: 3.7; 2023 IF: 3.836 |
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Call Number |
CMT @ cmt @c:irua:201287 |
Serial |
8976 |
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Author |
Sevik, C.; Bekaert, J.; Petrov, M.; Milošević, M.V. |
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Title |
High-temperature multigap superconductivity in two-dimensional metal borides |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Physical review materials |
Abbreviated Journal |
Phys. Rev. Materials |
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Volume |
6 |
Issue |
2 |
Pages |
024803 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Wos |
000766666300003 |
Publication Date |
2022-02-28 |
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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 |
2475-9953 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
4 |
Open Access |
Not_Open_Access |
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Notes |
Universiteit Antwerpen; Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, COST-118F187 ; Air Force Office of Scientific Research, FA9550-19-1-7048 ; Fonds Wetenschappelijk Onderzoek; |
Approved |
Most recent IF: 3.4 |
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| |
Call Number |
CMT @ cmt @c:irua:187126 |
Serial |
7047 |
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| Permanent link to this record |
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Author |
Menezes, R.M.; Šabani, D.; Bacaksiz, C.; de Souza Silva, C.C.; Milošević, M.V. |
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Title |
Tailoring high-frequency magnonics in monolayer chromium trihalides |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
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| |
Volume |
9 |
Issue |
2 |
Pages |
025021 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Monolayer chromium-trihalides, the archetypal two-dimensional (2D) magnetic materials, are readily suggested as a promising platform for high-frequency magnonics. Here we detail the spin-wave properties of monolayer CrBr<sub>3</sub>and CrI<sub>3</sub>, using spin-dynamics simulations parametrized from the first principles. We reveal that spin-wave dispersion can be tuned in a broad range of frequencies by strain, paving the way towards flexo-magnonic applications. We further show that ever-present halide vacancies in these monolayers host sufficiently strong Dzyaloshinskii-Moriya interaction to scatter spin-waves, which promotes design of spin-wave guides by defect engineering. Finally we discuss the spectra of spin-waves propagating across a moiré-periodic modulation of magnetic parameters in a van der Waals heterobilayer, and show that the nanoscale moiré periodicities in such samples are ideal for realization of a magnonic crystal in the terahertz frequency range. Recalling the additional tunability of magnetic 2D materials by electronic gating, our results situate these systems among the front-runners for prospective high-frequency magnonic applications. |
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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 |
000771735500001 |
Publication Date |
2022-04-01 |
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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 |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.5 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco; Special Research Funds of the University of Antwerp; Conselho Nacional de Desenvolvimento Científico e Tecnológico; Fonds Wetenschappelijk Onderzoek; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; |
Approved |
Most recent IF: 5.5 |
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| |
Call Number |
CMT @ cmt @c:irua:187125 |
Serial |
7048 |
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| Permanent link to this record |
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Author |
Chaves, A.; Covaci, L.; Peeters, F.M.; Milošević, M.V. |
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| |
Title |
Topologically protected moiré exciton at a twist-boundary in a van der Waals heterostructure |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
|
| |
Volume |
9 |
Issue |
2 |
Pages |
025012 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
A twin boundary in one of the layers of a twisted van der Waals heterostructure separates regions with near opposite inter-layer twist angles. In a MoS<sub>2</sub>/WSe<sub>2</sub>bilayer, the regions with<inline-formula><tex-math><?CDATA $Rh^h$?></tex-math><math overflow=“scroll”><msubsup><mi>R</mi><mi>h</mi><mi>h</mi></msubsup></math><inline-graphic href=“tdmac529dieqn1.gif” type=“simple” /></inline-formula>and<inline-formula><tex-math><?CDATA $Rh^X$?></tex-math><math overflow=“scroll”><msubsup><mi>R</mi><mi>h</mi><mi>X</mi></msubsup></math><inline-graphic href=“tdmac529dieqn2.gif” type=“simple” /></inline-formula>stacking registry that defined the sub-lattices of the moiré honeycomb pattern would be mirror-reflected across such a twist boundary. In that case, we demonstrate that topologically protected chiral moiré exciton states are confined at the twist boundary. These are one-dimensional and uni-directional excitons with opposite velocities for excitons composed by electronic states with opposite valley/spin character, enabling intrinsic, guided, and far reaching valley-polarized exciton currents. |
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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 |
000760518100001 |
Publication Date |
2022-04-01 |
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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 |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.5 |
Times cited |
3 |
Open Access |
OpenAccess |
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| |
Notes |
Fonds Wetenschappelijk Onderzoek; Conselho Nacional de Desenvolvimento Científico e Tecnológico, PQ ; |
Approved |
Most recent IF: 5.5 |
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| |
Call Number |
CMT @ cmt @c:irua:187124 |
Serial |
7046 |
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| Permanent link to this record |
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Author |
Bacaksiz, C.; Šabani, D.; Menezes, R.M.; Milošević, M.V. |
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Title |
Distinctive magnetic properties of CrI3 and CrBr3 monolayers caused by spin-orbit coupling |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
103 |
Issue |
12 |
Pages |
125418 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
After the discovery of magnetism in monolayer CrI3, the magnetic properties of different 2D materials from the chromium-trihalide family are intuitively assumed to be similar, yielding magnetic anisotropy from the spin-orbit coupling on halide ligands. Here we reveal significant differences between the CrI3 and CrBr3 magnetic monolayers in their magnetic anisotropy, resulting Curie temperature, hysteresis in external magnetic field, and evolution of magnetism with strain, all predominantly attributed to distinctly different interplay of atomic contributions to spin-orbit coupling in two materials. |
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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 |
000646179300003 |
Publication Date |
2021-03-17 |
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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 |
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Series Issue |
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Edition |
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| |
ISSN |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
18 |
Open Access |
OpenAccess |
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Notes |
Fonds Wetenschappelijk Onderzoek; Universiteit Antwerpen; |
Approved |
Most recent IF: 3.836 |
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Call Number |
CMT @ cmt @c:irua:177506 |
Serial |
6756 |
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| Permanent link to this record |
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Author |
Petrović, A. p.; Raju, M.; Tee, X. y.; Louat, A.; Maggio-Aprile, I.; Menezes, R. m.; Wyszyński, M. j.; Duong, N. k.; Reznikov, M.; Renner, C.; Milošević, M.V.; Panagopoulos, C. |
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Title |
Skyrmion-(Anti)Vortex Coupling in a Chiral Magnet-Superconductor Heterostructure |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys Rev Lett |
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| |
Volume |
126 |
Issue |
11 |
Pages |
117205 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report experimental coupling of chiral magnetism and superconductivity in [IrFeCoPt]/Nb heterostructures. The stray field of skyrmions with radius ~50nm is sufficient to nucleate antivortices in a 25nm Nb film, with unique signatures in the magnetization, critical current and flux dynamics, corroborated via simulations. We also detect a thermally-tunable Rashba-Edelstein exchange coupling in the isolated skyrmion phase. This realization of a strongly interacting skyrmion-(anti)vortex system opens a path towards controllable topological hybrid materials, unattainable to date. |
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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 |
000652825200011 |
Publication Date |
2021-03-17 |
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Series Editor |
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Series Title |
|
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 |
0031-9007 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.462 |
Times cited |
20 |
Open Access |
OpenAccess |
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| |
Notes |
National Research Foundation Singapore, NRFNRFI2015-04 ; Ministry of Education – Singapore, MOE2018-T3-1-002 ; Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, 182652 ; Fonds Wetenschappelijk Onderzoek; Universiteit Antwerpen; Flemish Government; European Cooperation in Science and Technology, CA16218 ; CalcUA Flemish Supercomputer Center; |
Approved |
Most recent IF: 8.462 |
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| |
Call Number |
CMT @ cmt @c:irua:177505 |
Serial |
6754 |
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| Permanent link to this record |
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Author |
González-García, A.; López-Pérez, W.; González-Hernández, R.; Bacaksiz, C.; Šabani, D.; Milošević, M.V.; Peeters, F.M. |
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Title |
Transition-metal adatoms on 2D-GaAs: a route to chiral magnetic 2D materials by design |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
33 |
Issue |
14 |
Pages |
145803 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using relativistic density-functional calculations, we examine the magneto-crystalline anisotropy and exchange properties of transition-metal atoms adsorbed on 2D-GaAs. We show that single Mn and Mo atom (Co and Os) strongly bind on 2D-GaAs, and induce local out-of-plane (in-plane) magnetic anisotropy. When a pair of TM atoms is adsorbed on 2D-GaAs in a close range from each other, magnetisation properties change (become tunable) with respect to concentrations and ordering of the adatoms. In all cases, we reveal presence of strong Dzyaloshinskii–Moriya interaction. These results indicate novel pathways towards two-dimensional chiral magnetic materials by design, tailored for desired applications in magneto-electronics. |
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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 |
000626453600001 |
Publication Date |
2021-04-07 |
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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 |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.649 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
|
Approved |
Most recent IF: 2.649 |
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Call Number |
CMT @ cmt @c:irua:177483 |
Serial |
6755 |
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Author |
Shi, W.; Callewaert, V.; Barbiellini, B.; Saniz, R.; Butterling, M.; Egger, W.; Dickmann, M.; Hugenschmidt, C.; Shakeri, B.; Meulenberg, R. W.; Brück, E.; Partoens, B.; Bansil, A.; Eijt, S.W. H. |
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Title |
Nature of the Positron State in CdSe Quantum Dots |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
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| |
Volume |
121 |
Issue |
5 |
Pages |
057401 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Previous studies have shown that positron-annihilation spectroscopy is a highly sensitive probe of the electronic structure and surface composition of ligand-capped semiconductor quantum dots (QDs) embedded in thin films. The nature of the associated positron state, however, whether the positron is confined inside the QDs or localized at their surfaces, has so far remained unresolved. Our positron-annihilation lifetime spectroscopy studies of CdSe QDs reveal the presence of a strong lifetime component in the narrow range of 358–371 ps, indicating abundant trapping and annihilation of positrons at the surfaces of the QDs. Furthermore, our ab initio calculations of the positron wave function and lifetime employing a recent formulation of the weighted density approximation demonstrate the presence of a positron surface state and predict positron lifetimes close to experimental values. Our study thus resolves the long-standing question regarding the nature of the positron state in semiconductor QDs and opens the way to extract quantitative information on surface composition and ligand-surface interactions of colloidal semiconductor QDs through highly sensitive positron-annihilation techniques. |
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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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Language |
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Wos |
000440635300012 |
Publication Date |
2018-08-02 |
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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 |
0031-9007 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.462 |
Times cited |
6 |
Open Access |
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Notes |
The work at Delft University of Technology was supported by the China Scholarship Council (CSC) grant of W. S. We acknowledge financial support for this research from ADEM, A green Deal in Energy Materials of the Ministry of Economic Affairs of The Netherlands. The PALS study is based upon experiments performed at the PLEPS instrument of the NEPOMUC facility at the Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany, and was supported by the European Commission under the 7th Framework Program, Key Action: Strengthening the European Research Area, Research Infrastructures, Contract No. 226507, NMI3. The work at the University of Maine was supported by the National Science Foundation under Grant No. DMR-1206940. V. C. and R. S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. Computational resources and services used in this work were in part provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government (EWI Department). The work at Northeastern University was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences Grant No. DE-FG02-07ER46352 (core research), and benefited from Northeastern University’s Advanced Scientific Computation Center (ASCC), the National Energy Research Scientific Computing Center (NERSC) through DOE Grant No. DE-AC02-05CH11231, and support (functionals for modeling positron spectros- copies of layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. |
Approved |
Most recent IF: 8.462 |
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| |
Call Number |
CMT @ cmt @c:irua:152999UA @ admin @ c:irua:152999 |
Serial |
5009 |
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| Permanent link to this record |
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Author |
Cavalcante, L.S.R.; Chaves, A.; Van Duppen, B.; Peeters, F.M.; Reichman, D.R. |
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Title |
Electrostatics of electron-hole interactions in van der Waals heterostructures |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
97 |
Issue |
12 |
Pages |
125427 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The role of dielectric screening of electron-hole interaction in van der Waals heterostructures is theoretically investigated. A comparison between models available in the literature for describing these interactions is made and the limitations of these approaches are discussed. A simple numerical solution of Poisson's equation for a stack of dielectric slabs based on a transfer matrix method is developed, enabling the calculation of the electron-hole interaction potential at very low computational cost and with reasonable accuracy. Using different potential models, direct and indirect exciton binding energies in these systems are calculated within Wannier-Mott theory, and a comparison of theoretical results with recent experiments on excitons in two-dimensional materials is 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 |
000427983700007 |
Publication Date |
2018-03-21 |
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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 |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
22 |
Open Access |
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Notes |
Discussions with A. Chernikov and A. Raja are gratefully acknowledged. This work has been financially supported by CNPq, through the PRONEX/FUNCAP, PQ, and Science Without Borders programs, and the FWO-CNPq bilateral program between Brazil and Flanders. B.V.D. acknowledges support from the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. D.R.R. was supported by NSF CHE-1464802. |
Approved |
Most recent IF: 3.836 |
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Call Number |
CMT @ cmt @c:irua:150835UA @ admin @ c:irua:150835 |
Serial |
4953 |
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| Permanent link to this record |
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Author |
Mulkers, J.; Van Waeyenberge, B.; Milošević, M.V. |
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Title |
Tunable Snell's law for spin waves in heterochiral magnetic films |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
97 |
Issue |
10 |
Pages |
104422 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Thin ferromagnetic films with an interfacially induced DMI exhibit nontrivial asymmetric dispersion relations that lead to unique and useful magnonic properties. Here we derive an analytical expression for the magnon propagation angle within the micromagnetic framework and show how the dispersion relation can be approximated with a comprehensible geometrical interpretation in the k space of the propagation of spin waves. We further explore the refraction of spin waves at DMI interfaces in heterochiral magnetic films, after deriving a generalized Snell's law tunable by an in-plane magnetic field, that yields analytical expressions for critical incident angles. The found asymmetric Brewster angles at interfaces of regions with different DMI strengths, adjustable by magnetic field, support the conclusion that heterochiral ferromagnetic structures are an ideal platform for versatile spin-wave guides. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000428238600006 |
Publication Date |
2018-03-26 |
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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 |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
20 |
Open Access |
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| |
Notes |
This work was supported by the Research Foundation- Flanders (FWO-Vlaanderen) through Project No. G098917N. |
Approved |
Most recent IF: 3.836 |
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| |
Call Number |
CMT @ cmt @c:irua:150118UA @ admin @ c:irua:150118 |
Serial |
4915 |
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Author |
Leliaert, J.; Mulkers, J.; De Clercq, J.; Coene, A.; Dvornik, M.; Van Waeyenberge, B. |
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Title |
Adaptively time stepping the stochastic Landau-Lifshitz-Gilbert equation at nonzero temperature: Implementation and validation in MuMax3 |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
AIP advances |
Abbreviated Journal |
Aip Adv |
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Volume |
7 |
Issue |
12 |
Pages |
125010 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Thermal fluctuations play an increasingly important role in micromagnetic research relevant for various biomedical and other technological applications. Until now, it was deemed necessary to use a time stepping algorithm with a fixed time step in order to perform micromagnetic simulations at nonzero temperatures. However, Berkov and Gorn have shown in [D. Berkov and N. Gorn, J. Phys.: Condens. Matter,14, L281, 2002] that the drift term which generally appears when solving stochastic differential equations can only influence the length of the magnetization. This quantity is however fixed in the case of the stochastic Landau-Lifshitz-Gilbert equation. In this paper, we exploit this fact to straightforwardly extend existing high order solvers with an adaptive time stepping algorithm. We implemented the presented methods in the freely available GPU-accelerated micromagnetic software package MuMax3 and used it to extensively validate the presented methods. Next to the advantage of having control over the error tolerance, we report a twenty fold speedup without a loss of accuracy, when using the presented methods as compared to the hereto best practice of using Heun’s solver with a small fixed time step. |
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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 |
000418492500010 |
Publication Date |
2017-12-11 |
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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 |
2158-3226 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.568 |
Times cited |
13 |
Open Access |
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Notes |
This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N and a postdoctoral fellowship (A.C.). J. L. is supported by the Ghent University Special Research Fund (BOF postdoctoral fellowship). We gratefully acknowl- edge the support of NVIDIA Corporation with the donation of the Titan Xp GPU used for this research. |
Approved |
Most recent IF: 1.568 |
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Call Number |
CMT @ cmt @c:irua:147860 |
Serial |
4799 |
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| Permanent link to this record |
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Author |
Callewaert, V.; Saniz, R.; Barbiellini, B.; Bansil, A.; Partoens, B. |
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Title |
Application of the weighted-density approximation to the accurate description of electron-positron correlation effects in materials |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
96 |
Issue |
8 |
Pages |
085135 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We discuss positron-annihilation lifetimes for a set of illustrative bulk materials within the framework of the weighted-density approximation (WDA). The WDA can correctly describe electron-positron correlations in strongly inhomogeneous systems, such as surfaces, where the applicability of (semi-)local approximations is limited. We analyze the WDA in detail and show that the electrons which cannot screen external charges efficiently, such as the core electrons, cannot be treated accurately via the pair correlation of the homogeneous electron gas. We discuss how this problem can be addressed by reducing the screening in the homogeneous electron gas by adding terms depending on the gradient of the electron density. Further improvements are obtained when core electrons are treated within the LDA and the valence electron using the WDA. Finally, we discuss a semiempirical WDA-based approach in which a sum rule is imposed to reproduce the experimental lifetimes. |
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Wos |
000408342600003 |
Publication Date |
2017-08-24 |
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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 |
2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
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Notes |
Fonds Wetenschappelijk Onderzoek, G. 0224.14N ; U.S. Department of Energy, DE-FG02-07ER46352 DE-AC02-05CH11231 DE-SC0012575 ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
CMT @ cmt @c:irua:145703 |
Serial |
4703 |
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Author |
Hafiz, H.; Suzuki, K.; Barbiellini, B.; Orikasa, Y.; Callewaert, V.; Kaprzyk, S.; Itou, M.; Yamamoto, K.; Yamada, R.; Uchimoto, Y.; Sakurai, Y.; Sakurai, H.; Bansil, A. |
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Title |
Visualizing redox orbitals and their potentials in advanced lithium-ion battery materials using high-resolution x-ray Compton scattering |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Science Advances |
Abbreviated Journal |
Sci. Adv. |
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Volume |
3 |
Issue |
8 |
Pages |
e1700971 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Reduction-oxidation (redox) reactions are the key processes that underlie the batteries powering smartphones, laptops, and electric cars. A redox process involves transfer of electrons between two species. For example, in a lithium-ion battery, current is generated when conduction electrons from the lithium anode are transferred to the redox orbitals of the cathode material. The ability to visualize or image the redox orbitals and how these orbitals evolve under lithiation and delithiation processes is thus of great fundamental and practical interest for understanding the workings of battery materials. We show that inelastic scattering spectroscopy using high-energy x-ray photons (Compton scattering) can yield faithful momentum space images of the redox orbitals by considering lithium iron phosphate (LiFePO4 or LFP) as an exemplar cathode battery material. Our analysis reveals a new link between voltage and the localization of transition metal 3d orbitals and provides insight into the puzzling mechanism of potential shift and how it is connected to the modification of the bond between the transition metal and oxygen atoms. Our study thus opens a novel spectroscopic pathway for improving the performance of battery materials. |
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Wos |
000411589900055 |
Publication Date |
2017-08-24 |
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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 |
2375-2548 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
9 |
Open Access |
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Notes |
The work at Northeastern University was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (grant no. DE-FG02-07ER46352) and benefited from the Northeastern University’s Advanced Scientific Computation Center and the National Energy Research Scientific Computing Center supercomputing center through DOE grant no. DEAC02-05CH11231. The work at Gunma University, Japan Synchrotron Radiation Research Institute (JASRI), and Kyoto University was supported by the Japan Science and Technology Agency. K.S. was supported by Grant-in-Aid for Young Scientists (B) from MEXT KAKENHI under grant nos. 24750065 and 15K17873. The Compton scattering experiments were performed with the approval of JASRI (proposal no. 2014A1289). V.C. was supported by the FWO-Vlaanderen through project no. G. 1161 0224.14N. |
Approved |
Most recent IF: NA |
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Call Number |
CMT @ cmt @c:irua:145034 |
Serial |
4637 |
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