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Records |
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Author |
Mahr, C.; Müller-Caspary, K.; Graf, M.; Lackmann, A.; Grieb, T.; Schowalter, M.; Krause, F.F.; Mehrtens, T.; Wittstock, A.; Weissmueller, J.; Rosenauer, A. |
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Title |
Measurement of local crystal lattice strain variations in dealloyed nanoporous gold |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Materials research letters |
Abbreviated Journal |
Mater Res Lett |
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| |
Volume |
6 |
Issue |
1 |
Pages |
84-92 |
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Keywords  |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Reversible macroscopic length changes in nanoporous structures can be achieved by applying electric potentials or by exposing them to different gases or liquids. Thus, these materials are interesting candidates for applications as sensors or actuators. Macroscopic length changes originate from microscopic changes of crystal lattice parameters. In this report, we show spatially resolved measurements of crystal lattice strain in dealloyed nanoporous gold. The results confirm theory by indicating a compression of the lattice along the axis of cylindrically shaped ligaments and an expansion in radial direction. Furthermore, we show that curved npAu surfaces show inward relaxation of the surface layer. [GRAPHICS] . |
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Corporate Author |
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Thesis |
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Publisher |
Taylor & Francis |
Place of Publication |
Abingdon |
Editor |
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Language |
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Wos |
000428141500013 |
Publication Date |
2017-11-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2166-3831 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.773 |
Times cited |
4 |
Open Access |
Not_Open_Access |
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Notes |
; This work has been supported by the Deutsche Forschungsgemeinschaft (DFG) under contracts no. RO2057/12-1 (SP 6), WI4497/1-1 (SP 2) and WE1424/17-1 (SP 3) within the research unit FOR2213 (www.nagocat.de). K.M.-C acknowledges support by the DFG under contract no. MU3660/1-1 and T.G. under contract no. RO2057/ 11-1. ; |
Approved |
Most recent IF: 4.773 |
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| |
Call Number |
UA @ lucian @ c:irua:150921 |
Serial |
4973 |
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| Permanent link to this record |
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Author |
Garud, S.; Gampa, N.; Allen, T.G.; Kotipalli, R.; Flandre, D.; Batuk, M.; Hadermann, J.; Meuris, M.; Poortmans, J.; Smets, A.; Vermang, B. |
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Title |
Surface passivation of CIGS solar cells using gallium oxide |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
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| |
Volume |
215 |
Issue |
7 |
Pages |
1700826 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
This work proposes gallium oxide grown by plasma-enhanced atomic layer deposition, as a surface passivation material at the CdS buffer interface of Cu(In,Ga)Se-2 (CIGS) solar cells. In preliminary experiments, a metal-insulator-semiconductor (MIS) structure is used to compare aluminium oxide, gallium oxide, and hafnium oxide as passivation layers at the CIGS-CdS interface. The findings suggest that gallium oxide on CIGS may show a density of positive charges and qualitatively, the least interface trap density. Subsequent solar cell results with an estimated 0.5nm passivation layer show an substantial absolute improvement of 56mV in open-circuit voltage (V-OC), 1mAcm(-2) in short-circuit current density (J(SC)), and 2.6% in overall efficiency as compared to a reference (with the reference showing 8.5% under AM 1.5G). |
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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 |
000430128500015 |
Publication Date |
2018-02-27 |
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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 |
1862-6300 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.775 |
Times cited |
8 |
Open Access |
Not_Open_Access |
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Notes |
; The work published in this paper was supported by the European Research Council (ERC) under the Union's Horizon 2020 research and innovation programme (grant agreement No 715027). The authors would also like to thank Dr. Marcel Simor (Solliance) for the CIGS layer fabrication and Prof. Johan Lauwaert (Universtiy of Ghent) for his guidance on DLTS measurements. ; |
Approved |
Most recent IF: 1.775 |
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Call Number |
UA @ lucian @ c:irua:150761 |
Serial |
4981 |
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Author |
Zhang, H.; Gauquelin, N.; McMahon, C.; Hawthorn, D.G.; Botton, G.A.; Wei, J.Y.T. |
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Title |
Synthesis of high-oxidation Y-Ba-Cu-O phases in superoxygenated thin films |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Physical review materials |
Abbreviated Journal |
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| |
Volume |
2 |
Issue |
3 |
Pages |
033803 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
It is known that solid-state reaction in high-pressure oxygen can stabilize high-oxidation phases of Y-Ba-Cu-O superconductors in powder form. We extend this superoxygenation concept of synthesis to thin films which, due to their large surface-to-volume ratio, are more reactive thermodynamically. Epitaxial thin films of YBa2Cu3O7-delta grown by pulsed laser deposition are annealed at up to 700 atm O-2 and 900 degrees C, in conjunction with Cu enrichment by solid-state diffusion. The films show the clear formation of Y2Ba4Cu7O15-delta and Y2Ba4Cu8O16 as well as regions of YBa2Cu5O9-delta and YBa2Cu6O10-delta phases, according to scanning transmission electron microscopy, x-ray diffraction, and x-ray absorption spectroscopy. Similarly annealed YBa2Cu3O7-delta powders show no phase conversion. Our results demonstrate a route of synthesis towards discovering more complex phases of cuprates and other superconducting oxides. |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
College Park, Md |
Editor |
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Language |
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Wos |
000428244900004 |
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 |
2475-9953 |
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 |
2 |
Open Access |
Not_Open_Access |
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Notes |
; This work is supported by NSERC, CFI-OIT, and CIFAR. The electron microscopy work was carried out at the Canadian Centre for Electron Microscopy, a National Facility supported by the Canada Foundation for Innovation under the Major Science Initiative program, McMaster University, and NSERC. The XAS work was performed at the Canadian Light Source, which is supported by NSERC, NRC, CIHR, and the University of Saskatchewan. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:150829 |
Serial |
4982 |
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Author |
Pearce, P.E.; Rousse, G.; Karakulina, O.M.; Hadermann, J.; Van Tendeloo, G.; Foix, D.; Fauth, F.; Abakumov, A.M.; Tarascon, J.-M. |
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Title |
β-Na1.7IrO3: A Tridimensional Na-Ion Insertion Material with a Redox Active Oxygen Network |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
30 |
Issue |
10 |
Pages |
3285-3293 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The revival of the Na-ion battery concept has prompted an intense search for new high capacity Na-based positive electrodes. Recently, emphasis has been placed on manipulating Na-based layered compounds to trigger the participation of the anionic network. We further explored this direction and show the feasibility of achieving anionic-redox activity in three-dimensional Na-based compounds. A new 3D β-Na1.7IrO3 phase was synthesized in a two-step process, which involves first the electrochemical removal of Li from β-Li2IrO3 to produce β-IrO3, which is subsequently reduced by electrochemical Na insertion. We show that β-Na1.7IrO3 can reversibly uptake nearly 1.3 Na+ per formula unit through an uneven voltage profile characterized by the presence of four plateaus related to structural transitions. Surprisingly, the β-Na1.7IrO3 phase was found to be stable up to 600 °C, while it could not be directly synthesized via conventional synthetic methods. Although these Na-based iridate phases are of limited practical interest, they help to understand how introducing highly polarizable guest ions (Na+) into host rocksalt-derived oxide structures affects the anionic redox mechanism. |
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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 |
000433403800014 |
Publication Date |
2018-05-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
OpenAccess |
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Notes |
The authors thank A. Perez for fruitful discussions and his valuable help in synchrotron XRD experiment and Matthieu Courty for carrying out the DSC measurements. The authors also greatly thank Matthieu Saubanère and Marie-Liesse Doublet for valuable discussions on theoretical aspects of this work. This work is based on experiments performed on the Materials Science and Powder Diffraction Beamline at ALBA synchrotron (Proposal 2016091814), Cerdanyola del Vallès, E- 08290 Barcelona, Spain. J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014)/ERC Grant- Project 670116-ARPEMA. G.R. acknowledges funding from ANR DeliRedox. O.M.K., J.H., and A.M.A. are grateful to FWO Vlaanderen for financial support under Grant G040116N. |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
EMAT @ emat @c:irua:152048 |
Serial |
4996 |
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| Permanent link to this record |
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Author |
Peters, J.L.; Altantzis, T.; Lobato, I.; Jazi, M.A.; van Overbeek, C.; Bals, S.; Vanmaekelbergh, D.; Sinai, S.B. |
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Title |
Mono- and Multilayer Silicene-Type Honeycomb Lattices by Oriented Attachment of PbSe Nanocrystals: Synthesis, Structural Characterization, and Analysis of the Disorder |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
30 |
Issue |
30 |
Pages |
4831-4837 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nanocrystal (NC) solids are commonly prepared from nonpolar organic NC suspensions. In many cases, the capping on the NC surface is preserved and forms a barrier between the NCs. More recently, superstructures with crystalline connections between the NCs, implying the removal of the capping, have been reported, too. Here, we present large-scale uniform superstructures of attached PbSe NCs with a silicene-type honeycomb geometry, resulting from solvent evaporation under nearly reversible conditions. We also prepared multilayered silicene honeycomb structures by using larger amounts of PbSe NCs. We show that the two-dimensional silicene superstructures can be seen as a crystallographic slice from a 3-D simple cubic structure. We describe the disorder in the silicene lattices in terms of the nanocrystals position and their atomic alignment. The silicene honeycomb sheets are large enough to be used in transistors and optoelectronic devices. |
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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 |
000440105500042 |
Publication Date |
2018-07-24 |
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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 |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
33 |
Open Access |
OpenAccess |
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Notes |
The authors acknowledge funding from the European Commission (Grant EUSMI 731019). S.B. acknowledges funding from the European Research Council (Grant 335078 COLOURATOM). T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO). The authors acknowledge financial support from the European Commission under the Horizon 2020 Programme by means of the Grant Agreement No. 731019 EUSMI. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ecas_sara |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
EMAT @ emat @c:irua:152997UA @ admin @ c:irua:152997 |
Serial |
5011 |
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| Permanent link to this record |
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Author |
Grimaud, A.; Iadecola, A.; Batuk, D.; Saubanere, M.; Abakumov, A.M.; Freeland, J.W.; Cabana, J.; Li, H.; Doublet, M.-L.; Rousse, G.; Tarascon, J.-M. |
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Title |
Chemical activity of the peroxide/oxide redox couple : case study of Ba5Ru2O11 in aqueous and organic solvents |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
30 |
Issue |
11 |
Pages |
3882-3893 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The finding that triggering the redox activity of oxygen ions within the lattice of transition metal oxides can boost the performances of materials used in energy storage and conversion devices such as Li-ion batteries or oxygen evolution electrocatalysts has recently spurred intensive and innovative research in the field of energy. While experimental and theoretical efforts have been critical in understanding the role of oxygen nonbonding states in the redox activity of oxygen ions, a clear picture of the redox chemistry of the oxygen species formed upon this oxidation process is still missing. This can be, in part, explained by the complexity in stabilizing and studying these species once electrochemically formed. In this work, we alleviate this difficulty by studying the phase Ba5Ru2O11, which contains peroxide O-2(2-) groups, as oxygen evolution reaction electrocatalyst and Li-ion battery material. Combining physical characterization and electrochemical measurements, we demonstrate that peroxide groups can easily be oxidized at relatively low potential, leading to the formation of gaseous dioxygen and to the instability of the oxide. Furthermore, we demonstrate that, owing to the stabilization at high energy of peroxide, the high-lying energy of the empty sigma* antibonding O-O states limits the reversibility of the electrochemical reactions when the O-2(2-)/O2- redox couple is used as redox center for Li-ion battery materials or as OER redox active sites. Overall, this work suggests that the formation of true peroxide O-2(2-) states are detrimental for transition metal oxides used as OER catalysts and Li-ion battery materials. Rather, oxygen species with O-O bond order lower than 1 would be preferred for these applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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Language |
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Wos |
000435416600038 |
Publication Date |
2018-05-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
2 |
Open Access |
Not_Open_Access |
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Notes |
; We thank S. Belin of the ROCK beamline (financed by the French National Research Agency (ANR) as a part of the “Investissements d'Avenir” program, reference: ANR-10-EQPX-45; proposal no. 20160095) of synchrotron SOLEIL for her assistance during XAS measurements. Authors would also like to thank V. Nassif for her assistance on the D1B beamline. A.G, G.R, and J.-M.T. acknowledge funding from the European Research Council (ERC) (FP/2014)/ERC Grant Project 670116-ARPEMA. ; |
Approved |
Most recent IF: 9.466 |
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Call Number |
UA @ lucian @ c:irua:151980 |
Serial |
5016 |
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Author |
Deshmukh, S.; Sankaran, K.J.; Srinivasu, K.; Korneychuk, S.; Banerjee, D.; Barman, A.; Bhattacharya, G.; Phase, D.M.; Gupta, M.; Verbeeck, J.; Leou, K.C.; Lin, I.N.; Haenen, K.; Roy, S.S. |
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Title |
Local probing of the enhanced field electron emission of vertically aligned nitrogen-doped diamond nanorods and their plasma illumination properties |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Diamond and related materials |
Abbreviated Journal |
Diam Relat Mater |
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Volume |
83 |
Issue |
83 |
Pages |
118-125 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A detailed conductive atomic force microscopic investigation is carried out to directly image the electron emission behavior for nitrogen-doped diamond nanorods (N-DNRs). Localized emission measurements illustrate uniform distribution of high-density electron emission sites from N-DNRs. Emission sites coupled to nano graphitic phases at the grain boundaries facilitate electron transport and thereby enhance field electron emission from N-DNRs, resulting in a device operation at low turn-on fields of 6.23 V/mu m, a high current density of 1.94 mA/cm(2) (at an applied field of 11.8 V/mu m) and a large field enhancement factor of 3320 with a long lifetime stability of 980 min. Moreover, using N-DNRs as cathodes, a microplasma device that can ignite a plasma at a low threshold field of 390 V/mm achieving a high plasma illumination current density of 3.95 mA/cm2 at an applied voltage of 550 V and a plasma life-time stability for a duration of 433 min was demonstrated. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000430767200017 |
Publication Date |
2018-02-07 |
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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 |
0925-9635 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.561 |
Times cited |
9 |
Open Access |
Not_Open_Access |
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Notes |
; S. Deshmulch, D. Banerjee and G. Bhattacharya are indebted to Shiv Nadar University for providing Ph.D. scholarships. K.J. Sankaran and K. Haenen like to thank the financial support of the Research Foundation Flanders (FWO) via Research Grant 12I8416N and Research Project 1519817N, and the Methusalem “NANO” network. K.J. Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). The Qu-Ant-EM microscope used for the TEM experiments was partly funded by the Hercules fund from the Flemish Government. S. Korneychuk and J. Verbeeck acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. ; |
Approved |
Most recent IF: 2.561 |
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Call Number |
UA @ lucian @ c:irua:151609UA @ admin @ c:irua:151609 |
Serial |
5030 |
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Author |
Quintanilla, M.; Zhang, Y.; Liz-Marzan, L.M. |
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Title |
Subtissue plasmonic heating monitored with CaF2:Nd3+,Y3+ nanothermometers in the second biological window |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
30 |
Issue |
8 |
Pages |
2819-2828 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Measuring temperature in biological environments is an ambitious goal toward supporting medical treatment and diagnosis. Minimally invasive techniques based on optical probes require very specific properties that are difficult to combine within a single material. These include high chemical stability in aqueous environments, optical signal stability, low toxicity, high emission intensity, and, essential, working at wavelengths within the biological transparency windows so as to minimize invasiveness while maximizing penetration depth. We propose CaF2:Nd3+,Y3+ as a candidate for thermometry based on an intraband ratiometric approach, fully working within the biological windows (excitation at 808 nm; emission around 1050 nm). We optimized the thermal probes through the addition of Y3+ as a dopant to improve both emission intensity and thermal sensitivity. To define the conditions under which the proposed technique can be applied, gold nanorods were used to optically generate subtissue hot areas, while the resulting temperature variation was monitored with the new nanothermometers. |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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Language |
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Wos |
000431088400038 |
Publication Date |
2018-03-27 |
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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 |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
28 |
Open Access |
Not_Open_Access |
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Notes |
; The authors would like to thank Dr. Guillermo Gonzalez Rubio for the kind support with the synthesis of gold nanorods. M.Q and L.M.L.-M. acknowledge financial support from the European Commission under the Marie Sklodowska-Curie program (H2020-MSCA-IF-2014_659021 – PHELLINI). Y.Z. acknowledges financial support from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 665501 through a FWO [PEGASUS]^2 Marie Sklodowska-Curie fellowship (12U4917N). ; |
Approved |
Most recent IF: 9.466 |
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Call Number |
UA @ lucian @ c:irua:151576 |
Serial |
5042 |
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Author |
Gkanatsiou, A.; Lioutas, C.B.; Frangis, N.; Polychroniadis, E.K.; Prystawko, P.; Leszczynski, M.; Altantzis, T.; Van Tendeloo, G. |
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Title |
Influence of 4H-SiC substrate miscut on the epitaxy and microstructure of AlGaN/GaN heterostructures |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Materials science in semiconductor processing |
Abbreviated Journal |
Mat Sci Semicon Proc |
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Volume |
91 |
Issue |
|
Pages |
159-166 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
AlGaN/GaN heterostructures were grown on “on-axis” and 2° off (0001) 4H-SiC substrates by metalorganic vapor phase epitaxy (MOVPE). Structural characterization was performed by transmission electron microscopy. The dislocation density, being greater in the on-axis case, is gradually reduced in the GaN layer and is forming
dislocation loops in the lower region. Steps aligned along [11̅00] in the off-axis case give rise to simultaneous defect formation. In the on-axis case, an almost zero density of steps is observed, with the main origin of defects probably being the orientation mismatch at the grain boundaries between the small not fully coalesced AlN grains. V-shaped formations are observed in the AlN nucleation layer, but are more frequent in the off-axis case, probably enhanced by the presence of steps. These V-shaped formations are completely overgrown by the GaN layer, during the subsequent deposition, presenting AlGaN areas in the walls of the defect, indicating an interdiffusion between the layers. Finally, at the AlGaN/GaN heterostructure surface in the on-axis case, V-shapes are observed, with the AlN spacer and AlGaN (21% Al) thickness on relaxed GaN exceeding the critical thickness for relaxation. On the other hand, no relaxation in the form of V-shape creation is observed in the off-axis case, probably due to the smaller AlGaN thickness (less than 21% Al). The AlN spacer layer, grown in between the heterostructure, presents a uniform thickness and clear interfaces. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000454537700022 |
Publication Date |
2018-11-26 |
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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 |
1369-8001 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.359 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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| |
Notes |
Funding: This work was supported by the IKY Fellowships of Excellence for Postgraduate Studies in Greece-SIEMENS Program; the Greek General Secretariat for Research and Technology, contract SAE 013/8–2009SE 01380012; and the JU ENIAC Project LAST POWER Large Area silicon carbide Substrates and heteroepitaxial GaN for POWER device applications [grant number 120218]. Also part of the research leading to these results has received funding from the European Union Seventh Framework Program under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative–I3). T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a post-doctoral grant. |
Approved |
Most recent IF: 2.359 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:156200 |
Serial |
5149 |
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| Permanent link to this record |
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| |
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Author |
Van Tendeloo, L.; Wangermez, W.; Vandekerkhove, A.; Willhammar, T.; Bals, S.; Maes, A.; Martens, J.A.; Kirschhock, C.E.A.; Breynaert, E. |
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| |
Title |
Postsynthetic high-alumina zeolite crystal engineering in organic free hyper-alkaline media |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
29 |
Issue |
29 |
Pages |
629-638 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Postsynthetic modification of high -alumina zeolites in hyper alkaline media can be tailored toward alteration of framework topology, crystal size and morphology, or desired Si/A1 ratio. FAU, EMT, MAZ, KFI, HEU, and LTA starting materials were treated with 1.2 M MOH (M = Na, K, RE, or Cs), leading to systematic ordered porosity or fully transformed frameworks with new topology and adjustable Si/Al ratio. In addition to the versatility of this tool for zeolite crystal engineering, these alterations improve understanding of the crystal chemistry. Such knowledge can guide further development in zeolite crystal engineering. Postsynthetic alteration also provides insight on the long-term stability of aluminosilicate zeolites that are used as a sorption sink in concrete -based waste disposal facilities in harsh alkaline conditions. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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| |
Language |
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Wos |
000392891700021 |
Publication Date |
2016-12-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
16 |
Open Access |
OpenAccess |
|
| |
Notes |
; This work was supported by long-term structural funding by the Flemish Government (Methusalem grant of Prof. J. Martens) and by ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and Fissile Materials, as part of the program on surface disposal of Belgian Category A waste. The Belgian government is acknowledged for financing the interuniversity poles of attraction (IAP-PAI). S.B. acknowledges financial support from European Research Council (ERC Advanced Grant No. 24691-COUNTATOMS, ERC Starting Grant No. 335078-COLOURATOMS). ; Ecas_Sara |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
UA @ lucian @ c:irua:152674UA @ admin @ c:irua:152674 |
Serial |
5145 |
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| Permanent link to this record |
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| |
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Author |
Korneychuk, S.; Guzzinati, G.; Verbeeck, J. |
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| |
Title |
Measurement of the Indirect Band Gap of Diamond with EELS in STEM |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
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| |
Volume |
215 |
Issue |
22 |
Pages |
1800318 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
In this work, a simple method to measure the indirect band gap of diamond with electron energy loss spectroscopy (EELS) in transmission electron microscopy (TEM) is showed. The authors discuss the momentum space resolution achievable with EELS and the possibility of deliberately selecting specific transitions of interest. Based on a simple 2 parabolic band model of the band structure, the authors extend our predictions from the direct band gap case discussed in previous work, to the case of an indirect band gap. Finally, the authors point out the emerging possibility to partly reconstruct the band structure with EELS exploiting our simplified model of inelastic scattering and support it with experiments on diamond. |
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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 |
000450818100004 |
Publication Date |
2018-07-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1862-6300 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.775 |
Times cited |
6 |
Open Access |
Not_Open_Access |
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| |
Notes |
S.K. and J.V. acknowledge funding from the “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint” of the University of Antwerp. Financial support via the Methusalem “NANO” network is acknowledged. G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint”; Methusalem “NANO” network; Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO); Hercules fund from the Flemish Government; |
Approved |
Most recent IF: 1.775 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:155402 |
Serial |
5138 |
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| Permanent link to this record |
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Author |
Leus, K.; Folens, K.; Nicomel, N.R.; Perez, J.P.H.; Filippousi, M.; Meledina, M.; Dirtu, M.M.; Turner, S.; Van Tendeloo, G.; Garcia, Y.; Du Laing, G.; Van Der Voort, P. |
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| |
Title |
Removal of arsenic and mercury species from water by covalent triazine framework encapsulated \gamma-Fe2O3 nanoparticles |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
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| |
Volume |
353 |
Issue |
353 |
Pages |
312-319 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The covalent triazine framework, CTF-1, served as host material for the in situ synthesis of Fe2O3 nanoparticles. The composite material consisted of 20 +/- 2 m% iron, mainly in gamma-Fe2O3 phase. The resulting gamma-Fe2O3@CTF-1 was examined for the adsorption of As-III, As-V and H-II from synthetic solutions and real surface-, ground- and wastewater. The material shows excellent removal efficiencies, independent from the presence of Ca2+, Mg2+ or natural organic matter and only limited dependency on the presence of phosphate ions. Its adsorption capacity towards arsenite (198.0 mg g(-1)), arsenate (102.3 mg g(-1)) and divalent mercury (165.8 mg g(-1)) belongs amongst the best-known adsorbents, including many other iron-based materials. Regeneration of the adsorbent can be achieved for use over multiple cycles without a decrease in performance by elution at 70 degrees C with 0.1 M NaOH, followed by a stirring step in a 5 m% H2O2 solution for As or 0.1 M thiourea and 0.001 M HCl for Hg. In highly contaminated water (100 mu gL(-1)), the adsorbent polishes the water quality to well below the current WHO limits. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000438002800035 |
Publication Date |
2018-04-16 |
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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 |
0304-3894 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
6.065 |
Times cited |
22 |
Open Access |
OpenAccess |
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| |
Notes |
; Karen Leus acknowledges financial support from Ghent University. Nina Ricci Nicomel and Jeffrey Paulo H. Perez thank the funding of the VLIR-UOS. Marinela M. Dirtu acknowledges F.R.S.-FNRS for a Charge de recherches position. Stuart Turner gratefully acknowledges the FWO Vlaanderen for a post-doctoral scholarship. The Titan microscope used for this investigation was partially funded by the Hercules foundation of the Flemish government. This work was supported by the Belgian IAP-PAI network. ; |
Approved |
Most recent IF: 6.065 |
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| |
Call Number |
UA @ lucian @ c:irua:152430 |
Serial |
5124 |
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| Permanent link to this record |
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| |
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Author |
Tessier, M.D.; Baquero, E.A.; Dupont, D.; Grigel, V.; Bladt, E.; Bals, S.; Coppel, Y.; Hens, Z.; Nayral, C.; Delpech, F. |
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| |
Title |
Interfacial oxidation and photoluminescence of InP-Based core/shell quantum dots |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
30 |
Issue |
30 |
Pages |
6877-6883 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Indium phosphide colloidal quantum dots (QDs) are emerging as an efficient cadmium-free alternative for optoelectronic applications. Recently, syntheses based on easy-to-implement aminophosphine precursors have been developed. We show by solid-state nuclear magnetic resonance spectroscopy that this new approach allows oxide-free indium phosphide core or core/shell quantum dots to be made. Importantly, the oxide-free core/shell interface does not help in achieving higher luminescence efficiencies. We demonstrate that in the case of InP/ZnS and InP/ZnSe QDs, a more pronounced oxidation concurs with a higher photoluminescence efficiency. This study suggests that a II-VI shell on a III-V core generates an interface prone to defects. The most efficient InP/ZnS or InP/ZnSe QDs are therefore made with an oxide buffer layer between the core and the shell: it passivates these interface defects but also results in a somewhat broader emission line width. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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| |
Language |
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Wos |
000447237800031 |
Publication Date |
2018-09-12 |
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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 |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
74 |
Open Access |
OpenAccess |
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| |
Notes |
; The authors thank L. Biadala and C. Delerue for fruitful discussion. Z.H. acknowledges support by the European Commission via the Marie-Sklodowska Curie action Phonsi (H2020-MSCA-ITN-642656), by Research Foundation Flanders (Project 17006602), and by Ghent University (GOA No. 01G01513). Z.H., M.D.T., and D.D. acknowledge the Strategisch Initiatief Materialen in Vlaanderen of Agentschap Innoveren en Ondernemen (SIM VLAIO), vzw (SBO-QDOCCO, ICON-QUALIDI). This work was supported by the Universite Paul Sabatier, the Region Midi-Pyrenees, the CNRS, the Institut National des Sciences Appliquees of Toulouse, and the Agence Nationale pour la Recherche (Project ANR-13-IS10-0004-01). E.A.B. is grateful to Marie Curie Actions and Campus France for a PRESTIGE postdoc fellowship (FP7 /2007-2013) under REA Grant Agreement PCOFUND-GA-2013-609102. E.B. acknowledges financial support from Research Foundation Flanders (FWO). ; |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
UA @ lucian @ c:irua:154732UA @ admin @ c:irua:154732 |
Serial |
5109 |
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| Permanent link to this record |
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Author |
Morozov, V.; Deyneko, D.; Basoyich, O.; Khaikina, E.G.; Spassky, D.; Morozov, A.; Chernyshev, V.; Abakumov, A.; Hadermann, J. |
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| |
Title |
Incommensurately modulated structures and luminescence properties of the AgxSm(2-x)/3WO4 (x=0.286, 0.2) scheelites as thermographic phosphors |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
30 |
Issue |
14 |
Pages |
4788-4798 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Ag+ for Sm3+ substitution in the scheelite-type AgxSm(2-x)/3 square(1-2x)/3WO4 tungstates has been investigated for its influence on the cation-vacancy ordering and luminescence properties. A solid state method was used to synthesize the x = 0.286 and x = 0.2 compounds, which exhibited (3 + 1)D incommensurately modulated structures in the transmission electron microscopy study. Their structures were refined using high resolution synchrotron powder X-ray diffraction data. Under near-ultraviolet light, both compounds show the characteristic emission lines for (4)G(5/2) -> H-6(J) (J = 5/2, 7/2, 9/2, and 11/2) transitions of the Sm3+ ions in the range 550-720 nm, with the J = 9/2 transition at the similar to 648 nm region being dominant for all photoluminescence spectra. The intensities of the (4)G(5/2) -> H-6(9/2) and (4)G(5/2) -> H-6(7/2) bands have different temperature dependencies. The emission intensity ratios (R) for these bands vary reproducibly with temperature, allowing the use of these materials as thermographic phosphors. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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Language |
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Wos |
000440105500037 |
Publication Date |
2018-06-21 |
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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 |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
2 |
Open Access |
Not_Open_Access |
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| |
Notes |
; This research was supported by FWO (Project G039211N), Flanders Research Foundation. The research was carried out within the state assignment of FASO of Russia (Themes No. 0339-2016-0007). V.M. thanks the Russian Foundation for Basic Research (Grant 18-03-00611) for financial support. E.G.K. and O.B. acknowledge financial support from the Russian Foundation for Basic Research (Grant 16-03-00510). D.D. thanks the Foundation of the Russian Federation President (Grant MK-3502.2018.5) for financial support. We are grateful to the ESRF for granting the beamtime. V.C. is grateful for the financial support of the Russian Ministry of Science and Education (Project No. RFMEFI61616X0069). We are grateful to the ESRF for the access to ID22 station (experiment MA-3313). ; |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
UA @ lucian @ c:irua:153156 |
Serial |
5107 |
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| Permanent link to this record |
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Author |
Volykhov, A.A.; Sanchez-Barriga, J.; Batuk, M.; Callaert, C.; Hadermann, J.; Sirotina, A.P.; Neudachina, V.S.; Belova, A.I.; Vladimirova, N.V.; Tamm, M.E.; Khmelevsky, N.O.; Escudero, C.; Perez-Dieste, V.; Knop-Gericke, A.; Yashina, L.V. |
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| |
Title |
Can surface reactivity of mixed crystals be predicted from their counterparts? A case study of (Bi1-xSbx)2Te3 topological insulators |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
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Volume |
6 |
Issue |
33 |
Pages |
8941-8949 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The behavior of ternary mixed crystals or solid solutions and its correlation with the properties of their binary constituents is of fundamental interest. Due to their unique potential for application in future information technology, mixed crystals of topological insulators with the spin-locked, gapless states on their surfaces attract huge attention of physicists, chemists and material scientists. (Bi1-xSbx)(2)Te-3 solid solutions are among the best candidates for spintronic applications since the bulk carrier concentration can be tuned by varying x to obtain truly bulk-insulating samples, where the topological surface states largely contribute to the transport and the realization of the surface quantum Hall effect. As this ternary compound will be evidently used in the form of thin-film devices its chemical stability is an important practical issue. Based on the atomic resolution HAADF-TEM and EDX data together with the XPS results obtained both ex situ and in situ, we propose an atomistic picture of the mixed crystal reactivity compared to that of its binary constituents. We find that the surface reactivity is determined by the probability of oxygen attack on the Te-Sb bonds, which is directly proportional to the number of Te atoms bonded to at least one Sb atom. The oxidation mechanism includes formation of an amorphous antimony oxide at the very surface due to Sb diffusion from the first two quintuple layers, electron tunneling from the Fermi level of the crystal to oxygen, oxygen ion diffusion to the crystal, and finally, slow Te oxidation to the +4 oxidation state. The oxide layer thickness is limited by the electron transport, and the overall process resembles the Cabrera-Mott mechanism in metals. These observations are critical not only for current understanding of the chemical reactivity of complex crystals, but also to improve the performance of future spintronic devices based on topological materials. |
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Corporate Author |
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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 |
000443279300007 |
Publication Date |
2018-07-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2050-7526; 2050-7534 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.256 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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| |
Notes |
; The authors acknowledge financial support within the bilateral program "Russian-German Laboratory at BESSY II''. We thank Helmholtz-Zentrum Berlin for granting access to the beamlines RGBL, UE112-PGM2a and ISISS. Support of ALBA staff during measurements at the CIRCE beamline is gratefully acknowledged. We thank Dr Ivan Bobrikov for support in the XRD measurements and Daria Tsukanova for the participation in crystal preparation and XPS measurements. A. Volykhov thanks RSF (grant 18-73-00248) for financial support. A. I. Belova acknowledges support from the G-RISC Centre of Excellence. The work was supported by Helmholtz Gemeinschaft (Grant No. HRJRG-408) and RFBR (grant 14-03-31518). J. H. and C. C. acknowledge support from the University of Antwerp through the BOF grant 31445. ; |
Approved |
Most recent IF: 5.256 |
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| |
Call Number |
UA @ lucian @ c:irua:153647 |
Serial |
5080 |
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| Permanent link to this record |
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Author |
Guzzinati, G.; Altantzis, T.; Batuk, M.; De Backer, A.; Lumbeeck, G.; Samaee, V.; Batuk, D.; Idrissi, H.; Hadermann, J.; Van Aert, S.; Schryvers, D.; Verbeeck, J.; Bals, S. |
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Title |
Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Materials |
Abbreviated Journal |
Materials |
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| |
Volume |
11 |
Issue |
11 |
Pages |
1304 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science. |
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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 |
000444112800041 |
Publication Date |
2018-07-28 |
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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 |
1996-1944 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.654 |
Times cited |
15 |
Open Access |
OpenAccess |
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Notes |
Fonds Wetenschappelijk Onderzoek, G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N AUHA13009 ; European Research Council, COLOURATOM 335078 ; Universiteit Antwerpen, GOA Solarpaint ; G. Guzzinati, T. Altantzis and A. De Backer have been supported by postdoctoral fellowship grants from the Research Foundation Flanders (FWO). Funding was also received from the European Research Council (starting grant no. COLOURATOM 335078), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 770887), the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N, G.0401.16N) and from the University of Antwerp through GOA project Solarpaint. Funding for the TopSPIN precession system under grant AUHA13009, as well as for the Qu-Ant-EM microscope, is acknowledged from the HERCULES Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (F.R.S.-FNRS). (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; |
Approved |
Most recent IF: 2.654 |
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| |
Call Number |
EMAT @ emat @c:irua:153737UA @ admin @ c:irua:153737 |
Serial |
5064 |
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| Permanent link to this record |
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Author |
Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q. |
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Title |
Study of the Q′ (Q)-phase precipitation in Al–Mg–Si–Cu alloys by quantification of atomic-resolution transmission electron microscopy images and atom probe tomography |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of materials science |
Abbreviated Journal |
J Mater Sci |
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| |
Volume |
54 |
Issue |
10 |
Pages |
7943-7952 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The precipitation mechanism of the Q phase in Al-Mg-Si-Cu alloys has long been the subject of ambiguity and debate since its metastable phase (Q 0) has the same crystal structure and similar lattice parameters as its equilibrium counterparts. In the present work, the evolution of the Q 0 (Q) phase during aging is studied by combination of quantitative atomic-resolution scanning transmission electron microscopy and atom probe tomography. It was found that the transformation from the Q 0 to the Q phase involves changes of the occupancy of Al atoms in atomic columns of the Q 0 (Q) phase. The Al atoms incorporated in the Cu, Si and Mg columns are gradually released into the Al matrix, while mixing between Cu and Si atoms occurs in the Si columns. This transformation process is mainly attributed to the low lattice misfit of the equilibrium Q phase. Besides, the formation of various compositions of the Q phase is due to the different occupancy in the atomic columns of the Q phase. The occupancy changes in the columns of the Q phase are kinetically controlled and are strongly influenced by the alloy composition and aging temperature. |
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Wos |
000460069500043 |
Publication Date |
2019-02-14 |
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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 |
0022-2461 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.599 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing, cstc2017zdcy-zdzxX0006 ; Fundamental Research Funds for the Central Universities of China, 2018CDGFCL0002 106112017CDJQJ308822 ; Belgian National Fund for Scientific Research; the National Natural Science Foundation of China, 51871035 ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant No. cstc2017zdcyzdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDGFCL0002), the National Natural Science Foundation of China (Grant No. 51871035) and the Foundation for Innovative Research Groups J Mater Sci National Natural Science Foundation of China (Grant No. 51421001). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). |
Approved |
Most recent IF: 2.599 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:158112 |
Serial |
5158 |
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| Permanent link to this record |
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Author |
Miotti Bettanini, A.; Ding, L.; Mithieux, J.-D.; Parrens, C.; Idrissi, H.; Schryvers, D.; Delannay, L.; Pardoen, T.; Jacques, P.J. |
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Title |
Influence of M23C6 dissolution on the kinetics of ferrite to austenite transformation in Fe-11Cr-0.06C stainless steel |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Materials & design |
Abbreviated Journal |
Mater Design |
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Volume |
162 |
Issue |
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Pages |
362-374 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The design of high-strength martensitic stainless steels requires an accurate control over the stability of undesired phases, like carbides and ferrite, which can hamper strength and ductility. Here, the ferrite to austenite transformation in Fe-11Cr-0.06C has been studied with a combined experimental-modelling approach. Experimental observations of the austenization process indicate that austenite growth proceeds in multiple steps, each one characterized by a different transformation rate. DICTRA based modelling reveals that the dissolution of the M23C6 Cr-rich carbides leads to Cr partitioning between austenite and parent phases, which controls the rate of transformation through (i) a soft-impingement effect and (ii) consequent stabilization of the ferrite, which remains untransformed inside chromium-enriched-zones even after prolonged austenization stage. Slow heating rate and smaller initial particle sizes allow the design of ferrite-free microstructure. |
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Wos |
000454128400036 |
Publication Date |
2018-12-06 |
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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 |
0264-1275 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.364 |
Times cited |
3 |
Open Access |
OpenAccess |
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Notes |
The authors thank Professor Anne-Francoise Gourgues-Lorenzon and Helene Godin, Ecole Nationale Superiore des Mines de Paris (MINES ParisTech) for their fruitful discussions. AMB thanks Stijn Van den broek (Universiteit Antwerpen) for the skillful preparation of TEM samples with FIB. The financial support of CBMM (Companhia Brasileira de Metalurgia e Mineracao) is gratefully acknowledged. L. Delannay is mandated by the FNRS-Belgium. Computational resources have been provided by the supercomputing facilities of the UCLouvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en Federation Wallonie Bruxelles (CÉCI) funded by the Fond de la Recherche Scientifique de Belgique (F.R.S.-FNRS) under convention 2.5020.11.; Cbmm; F.r.s.-fnrs, 2.5020.11 ; |
Approved |
Most recent IF: 4.364 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:156721 |
Serial |
5161 |
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| Permanent link to this record |
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Author |
Scarabelli, L.; Schumacher, M.; Jimenez de Aberasturi, D.; Merkl, J.‐P.; Henriksen‐Lacey, M.; Milagres de Oliveira, T.; Janschel, M.; Schmidtke, C.; Bals, S.; Weller, H.; Liz‐Marzán, L.M. |
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Title |
Encapsulation of Noble Metal Nanoparticles through Seeded Emulsion Polymerization as Highly Stable Plasmonic Systems |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
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Volume |
29 |
Issue |
29 |
Pages |
1809071 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The implementation of plasmonic nanoparticles in vivo remains hindered by important limitations such as biocompatibility, solubility in biological fluids, and physiological stability. A general and versatile protocol is presented, based on seeded emulsion polymerization, for the controlled encapsulation of gold and silver nanoparticles. This procedure enables the encapsulation of single nanoparticles as well as nanoparticle clusters inside a protecting polymer shell. Specifically, the efficient coating of nanoparticles of both metals is demonstrated, with final dimensions ranging between 50 and 200 nm, i.e., sizes of interest for bio-applications. Such hybrid nanocomposites display extraordinary stability in high ionic strength and oxidizing environments, along with high cellular uptake, and low cytotoxicity. Overall, the prepared nanostructures are promising candidates for plasmonic applications under biologically relevant conditions. |
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Wos |
000467109100024 |
Publication Date |
2019-02-11 |
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Series Editor |
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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 |
1616-301X |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.124 |
Times cited |
19 |
Open Access |
OpenAccess |
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Notes |
L.S. and M.S. contributed equally to this work. This work was supported by the Spanish MINECO (Grant MAT2017-86659-R), by the German Research Foundation (DFG, Grant LA 2901/1-1) and by the European Research Council (Grant 335078 COLOURATOM to S.B). The authors acknowledge funding from the European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M). L.S. acknowledges funding from the American-Italian Cancer Foundation through a Post-Doctoral Research Fellowship. D.J.d.A. thanks MINECO for a Juan de la Cierva fellowship (IJCI-2015-24264). J.P.M. was financed by Verband der Chemischen Industrie e.V. (VCI). The authors thank Dr. Artur Feld, Dr. Andreas Kornowski and Stefan Werner (Institute of Physical Chemistry, University of Hamburg) for their support. |
Approved |
Most recent IF: 12.124 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:160710 |
Serial |
5190 |
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Author |
Montero-Sistiaga, M.L.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D.; Vanmeensel, K. |
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Title |
Microstructure and mechanical properties of Hastelloy X produced by HP-SLM (high power selective laser melting) |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Materials & design |
Abbreviated Journal |
Mater Design |
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Volume |
165 |
Issue |
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Pages |
107598 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In order to increase the production rate during selective laser melting (SLM), a high power laser with a large beam diameter is used to build fully dense Hastelloy X parts. Compared to SLM with a low power and small diameter beam, the productivity was increased from 6 mm3/s to 16 mm3/s, i.e. 2.6 times faster. Besides the productivity benefit, the influence of the use of a high power laser on the rapid solidification microstructure and concomitant material properties is highlighted. The current paper compares the microstructure and tensile properties of Hastelloy X built with low and high power lasers. The use of a high power laser results in wider and shallower melt pools inducing an enhanced morphological and crystallographic texture along the building direction (BD). In addition, the increased heat input results in coarser sub-grains or high density dislocation walls for samples processed with a high power laser. Additionally, the influence of hot isostatic pressing (HIP) as a post-processing technique was evaluated. After HIP, the tensile fracture strain increased as compared to the strain in the as-built state and helped in obtaining competitive mechanical properties as compared to conventionally processed Hastelloy X parts. |
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Wos |
000458259300020 |
Publication Date |
2019-01-09 |
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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 |
0264-1275 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.364 |
Times cited |
15 |
Open Access |
OpenAccess |
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Notes |
This research was supported by the ENGIE Research and Technology Division. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine. S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. |
Approved |
Most recent IF: 4.364 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:157469 |
Serial |
5176 |
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Author |
Yin, C.; Krishnan, D.; Gauquelin, N.; Verbeeck, J.; Aarts, J. |
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Title |
Controlling the interfacial conductance in LaAlO3/SrTiO3 in 90 degrees off-axis sputter deposition |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
3 |
Issue |
3 |
Pages |
034002 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the fabrication of conducting interfaces between LaAlO3 and SrTiO3 by 90 degrees off-axis sputtering in an Ar atmosphere. At a growth pressure of 0.04 mbar the interface is metallic, with a carrier density of the order of 1 x 10(13) cm(-2) at 3 K. By increasing the growth pressure, we observe an increase of the out-of-plane lattice constants of the LaAlO3 films while the in-plane lattice constants do not change. Also, the low-temperature sheet resistance increases with increasing growth pressure, leading to an insulating interface when the growth pressure reaches 0.10 mbar. We attribute the structural variations to an increase of the La/Al ratio, which also explains the transition from metallic behavior to insulating behavior of the interfaces. Our research shows that the control which is furnished by the Ar pressure makes sputtering as versatile a process as pulsed laser deposition, and emphasizes the key role of the cation stoichiometry of LaAlO3 in the formation of the conducting interface. |
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Wos |
000461077100002 |
Publication Date |
2019-03-12 |
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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 |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.926 |
Times cited |
4 |
Open Access |
Not_Open_Access |
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Notes |
; We thank Nikita Lebedev, Aymen Ben Hamida, and Prateek Kumar for useful discussions and Giordano Mattoni, Jun Wang, Vincent Joly, and Hozanna Miro for their technical assistance. We also thank Jean-Marc Triscone and his group for sharing their design of the sputtering system with us. This work is part of the FOM research programme DESCO with Project No. 149, which is (partly) financed by the Netherlands Organisation for Scientific Research (NWO). C.Y. is supported by China Scholarship Council (CSC) with Grant No. 201508110214. N.G., D.K., and J.V. acknowledge financial support from the GOA project “Solarpaint” of the University of Antwerp. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:158547 |
Serial |
5243 |
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Author |
Akkerman, Q.A.; Bladt, E.; Petralanda, U.; Dang, Z.; Sartori, E.; Baranov, D.; Abdelhady, A.L.; Infante, I.; Bals, S.; Manna, L. |
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Title |
Fully inorganic Ruddlesden-Popper double CI-I and triple CI-Br-I lead halide perovskite nanocrystals |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
31 |
Issue |
31 |
Pages |
2182-2190 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The vast majority of lead halide perovskite (LHP) nanocrystals (NCs) are currently based on either a single halide composition (CsPbCl3, CsPbBr3, and CsPbI3) or an alloyed mixture of bromide with either Cl- or I- [i.e., CsPb(Br:Cl)(3) or CsPb(Br:I)(3)]. In this work, we present the synthesis as well as a detailed optical and structural study of two halide alloying cases that have not previously been reported for LHP NCs: Cs2PbI2Cl2 NCs and triple halide CsPb(Cl:Br:I)(3) NCs. In the case of Cs2PbI2Cl2, we observe for the first time NCs with a fully inorganic Ruddlesden-Popper phase (RPP) crystal structure. Unlike the well-explored organic-inorganic RPP, here, the RPP formation is triggered by the size difference between the halide ions. These NCs exhibit a strong excitonic absorption, albeit with a weak photoluminescence quantum yield (PLQY). In the case of the triple halide CsPb(Cl:Br:I)(3) composition, the NCs comprise a CsPbBr2Cl perovskite crystal lattice with only a small amount of incorporated iodide, which segregates at RPP planes' interfaces within the CsPb(Cl:Br:I)(3) NCs. Supported by density functional theory calculations and postsynthetic surface treatments to enhance the PLQY, we show that the combination of iodide segregation and defective RPP interfaces are most likely linked to the strong PL quenching observed in these nanostructures. In summary, this work demonstrates the limits of halide alloying in LHP NCs because a mixture that contains halide ions of very different sizes leads to the formation of defective RPP interfaces and a severe quenching of LHP NC's optical properties. |
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Place of Publication |
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Wos |
000462950400038 |
Publication Date |
2019-03-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
58 |
Open Access |
OpenAccess |
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Notes |
; Q.A.A. and L.M. acknowledge funding from the European Union Seventh Framework Programme under grant agreement no. 614897 (ERC Consolidator Grant “TRANS-NANO”). The work of D.B. was supported by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 794560. E.B. and S.B. acknowledge funding from the Research Foundation Flanders (G.038116N, G.03691, and funding of a postdoctoral grant to E.B.). I.I. acknowledges The Netherlands Organization of Scientific Research (NWO) for financial support through the Innovational Research Incentive (Vidi) Scheme (grant no. 723.013.002). The computational work was carried out on the Dutch national e-infrastructure with the support of the SURF Cooperative. ; |
Approved |
Most recent IF: 9.466 |
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Call Number |
UA @ admin @ c:irua:159414 |
Serial |
5250 |
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Author |
Zhang, G.; Zhou, Y.; Korneychuk, S.; Samuely, T.; Liu, L.; May, P.W.; Xu, Z.; Onufriienko, O.; Zhang, X.; Verbeeck, J.; Samuely, P.; Moshchalkov, V.V.; Yang, Z.; Rubahn, H.-G. |
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Title |
Superconductor-insulator transition driven by pressure-tuned intergrain coupling in nanodiamond films |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
3 |
Issue |
3 |
Pages |
034801 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the pressure-driven superconductor-insulator transition in heavily boron-doped nanodiamond films. By systematically increasing the pressure, we suppress the Josephson coupling between the superconducting nanodiamond grains. The diminished intergrain coupling gives rise to an overall insulating state in the films, which is interpreted in the framework of a parallel-series circuit model to be the result of bosonic insulators with preserved localized intragrain superconducting order parameters. Our investigation opens up perspectives for the application of high pressure in research on quantum confinement and coherence. Our data unveil the percolative nature of the electrical transport in nanodiamond films, and highlight the essential role of grain boundaries in determining the electronic properties of this material. |
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Wos |
000460684600002 |
Publication Date |
2019-03-05 |
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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 |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.926 |
Times cited |
5 |
Open Access |
Not_Open_Access |
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Notes |
; Y.Z. and Z.Y. acknowledge support from the National Key Research and Development Program of China (Grants No. 2018YFA0305700 and No. 2016YFA0401804), the National Natural Science Foundation of China (Grants No. 11574323, No. 11704387, and No. U1632275), the Natural Science Foundation of Anhui Province (Grants No. 1708085QA19 and No. 1808085MA06), and the Director's Fund of Hefei Institutes of Physical Science, Chinese Academy of Sciences (YZJJ201621). J.V. and S.K. acknowledge funding from the GOA project “Solarpaint” of the University of Antwerp, and thank the FWO (Research Foundation-Flanders) for financial support under Contract No. G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. T.S., O.O., and P.S. are supported by APVV-0036-11, APVV-0605-14, VEGA 1/0409/15, VEGA 2/0149/16, and EU ERDF-ITMS 26220120005. L.L. acknowledges the financial support of a FWO postdoctoral research fellowship (12V4419N) and the KU Leuven C1 project OPTIPROBE (C14/16/ 063). ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:158561 |
Serial |
5260 |
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| Permanent link to this record |
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Author |
Tan, X.; Stephens, P.W.; Hendrickx, M.; Hadermann, J.; Segre, C.U.; Croft, M.; Kang, C.-J.; Deng, Z.; Lapidus, S.H.; Kim, S.W.; Jin, C.; Kotliar, G.; Greenblatt, M. |
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Title |
Tetragonal Cs1.17In0.81Cl3 : a charge-ordered indium halide perovskite derivative |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
31 |
Issue |
6 |
Pages |
1981-1989 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Polycrystalline samples of Cs1.17In0.81Cl3 were prepared by annealing a mixture of CsCl, InCl, and InCl3, stoichiometric for the targeted CsInCl3. Synchrotron powder X-ray diffraction refinement and chemical analysis by energy dispersive X-ray indicated that Cs1.17In0.81Cl3, a tetragonal distorted perovskite derivative (I4/m), is the thermodynamically stable product. The refined unit cell parameters and space group were confirmed by electron diffraction. In the tetragonal structure, In+ and In3+ are located in four different crystallographic sites, consistent with their corresponding bond lengths. In1, In2, and In3 are octahedrally coordinated, whereas In4 is at the center of a pentagonal bipyramid of Cl because of the noncooperative octahedral tilting of In4Cl6. The charged-ordered In+ and In3+ were also confirmed by X-ray absorption and Raman spectroscopy. Cs1.17In0.81Cl3 is the first example of an inorganic halide double perovskite derivative with charged-ordered In+ and In3+. Band structure and optical conductivity calculations were carried out with both generalized gradient approximation (GGA) and modified Becke-Johnson (mBJ) approach; the GGA calculations estimated the band gap and optical band gap to be 2.27 eV and 2.4 eV, respectively. The large and indirect band gap suggests that Cs1.17In0.81Cl3 is not a good candidate for photovoltaic application. |
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Place of Publication |
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Language |
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Wos |
000462950400017 |
Publication Date |
2019-02-19 |
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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 |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
OpenAccess |
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Notes |
; M.G. and X.T. were supported by the Center for Computational Design of Functional Strongly Correlated Materials and Theoretical Spectroscopy under DOE Grant No. DE-FOA-0001276. M.G. also acknowledges support of NSF-DMR-1507252 grant. G.K. and C.-J.K. were supported by the Air Force Office of Scientific Research. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. The use of the Advanced Photon Source at the Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The works at IOPCAS were supported by NSF & MOST of China through research projects. ; |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
UA @ admin @ c:irua:159413 |
Serial |
5262 |
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| Permanent link to this record |
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Author |
Tan, X.; McCabe, E.E.; Orlandi, F.; Manuel, P.; Batuk, M.; Hadermann, J.; Deng, Z.; Jin, C.; Nowik, I.; Herber, R.; Segre, C.U.; Liu, S.; Croft, M.; Kang, C.-J.; Lapidus, S.; Frank, C.E.; Padmanabhan, H.; Gopalan, V.; Wu, M.; Li, M.-R.; Kotliar, G.; Walker, D.; Greenblatt, M. |
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Title |
MnFe0.5Ru0.5O3 : an above-room-temperature antiferromagnetic semiconductor |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
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Volume |
7 |
Issue |
3 |
Pages |
509-522 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A transition-metal-only MnFe0.5Ru0.5O3 polycrystalline oxide was prepared by a reaction of starting materials MnO, MnO2, Fe2O3, RuO2 at 6 GPa and 1873 K for 30 minutes. A combination of X-ray and neutron powder diffraction refinements indicated that MnFe0.5Ru0.5O3 adopts the corundum (alpha-Fe2O3) structure type with space group R (3) over barc, in which all metal ions are disordered. The centrosymmetric nature of the MnFe0.5Ru0.5O3 structure is corroborated by transmission electron microscopy, lack of optical second harmonic generation, X-ray absorption near edge spectroscopy, and Mossbauer spectroscopy. X-ray absorption near edge spectroscopy of MnFe0.5Ru0.5O3 showed the oxidation states of Mn, Fe, and Ru to be 2+/3+, 3+, and similar to 4+, respectively. Resistivity measurements revealed that MnFe0.5Ru0.5O3 is a semiconductor. Magnetic measurements and magnetic structure refinements indicated that MnFe0.5Ru0.5O3 orders antiferromagnetically around 400 K, with magnetic moments slightly canted away from the c axis. Fe-57 Mossbauer confirmed the magnetic ordering and Fe3+ (S = 5/2) magnetic hyperfine splitting. First principles calculations are provided to understand the electronic structure more thoroughly. A comparison of synthesis and properties of MnFe0.5Ru0.5O3 and related corundum Mn2BB'O-6 derivatives is discussed. |
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Wos |
000458780300004 |
Publication Date |
2018-11-27 |
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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 |
2050-7526; 2050-7534 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.256 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
; M. G. thanks the NSF-DMR-1507252 grant of the United States. X. T. was supported by the “Center for Computational Design of Functional Strongly Correlated Materials and Theoretical Spectroscopy'' under DOE Grant No. DE-FOA-0001276. G. K. and C. J. K. were supported by the Air Force Office of Scientific Research. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. EEM is grateful to the Leverhulme Trust (RPG-2017-362). M. R. Li and M. X. Wu are supported by the ”One Thousand Youth Talents'' Program of China. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Part of this research used the ISS, 8-ID and TES, 8-BM beamlines at the National Synchrotron Light Source II (NSLS-II), a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. Without the valuable aid/support of the NSLS-II staff scientists Eli Stavitski, Klaus Attenkofer, and Paul Northrup this phase of the work could not have been performed. The work at IOPCAS was supported by NSF & MOST of China through research projects. H. R. and V. G. acknowledge NSF-MRSEC Center for Nanoscale Science at Penn State through the grant number DMR-1420620. The authors would like to thank Ms Jean Hanley at Lamont-Doherty Earth Observatory in Columbia University for making the high-pressure assemblies. The authors acknowledge the science and technology facility council (STFC) UK for the provision of neutron beam time. The authors would like to thank Daniel Nye for help on the Rigaku SmartLab X-ray diffractometer instrument in the Materials Characterization Laboratory at the ISIS Neutron and Muon Source. ; |
Approved |
Most recent IF: 5.256 |
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Call Number |
UA @ admin @ c:irua:157564 |
Serial |
5264 |
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| Permanent link to this record |
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Author |
Choudhary, K.; Bercx, M.; Jiang, J.; Pachter, R.; Lamoen, D.; Tavazza, F. |
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Title |
Accelerated Discovery of Efficient Solar Cell Materials Using Quantum and Machine-Learning Methods |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
31 |
Issue |
15 |
Pages |
5900-5908 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Solar energy plays an important role in solving serious environmental
problems and meeting the high energy demand. However, the lack of suitable
materials hinders further progress of this technology. Here, we present the largest
inorganic solar cell material search till date using density functional theory (DFT) and
machine-learning approaches. We calculated the spectroscopic limited maximum
efficiency (SLME) using the Tran−Blaha-modified Becke−Johnson potential for 5097
nonmetallic materials and identified 1997 candidates with an SLME higher than 10%,
including 934 candidates with a suitable convex-hull stability and an effective carrier
mass. Screening for two-dimensional-layered cases, we found 58 potential materials
and performed G0W0 calculations on a subset to estimate the prediction uncertainty. As the above DFT methods are still computationally expensive, we developed a high accuracy machine-learning model to prescreen efficient materials and applied it to over a million materials. Our results provide a general framework and universal strategy for the design of high-efficiency solar
cell materials. The data and tools are publicly distributed at: https://www.ctcms.nist.gov/~knc6/JVASP.html, https://www.
ctcms.nist.gov/jarvisml/, https://jarvis.nist.gov/, and https://github.com/usnistgov/jarvis. |
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Wos |
000480826900060 |
Publication Date |
2019-08-13 |
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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 |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:161814 |
Serial |
5291 |
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| Permanent link to this record |
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Author |
Keunecke, M.; Lyzwa, F.; Schwarzbach, D.; Roddatis, V.; Gauquelin, N.; Müller-Caspary, K.; Verbeeck, J.; Callori, S.J.; Klose, F.; Jungbauer, M.; Moshnyaga, V. |
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Title |
High-TCInterfacial Ferromagnetism in SrMnO3/LaMnO3Superlattices |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv. Funct. Mater. |
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Volume |
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Issue |
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Pages |
1808270 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Heterostructures of strongly correlated oxides demonstrate various intriguing and potentially useful interfacial phenomena. LaMnO3/SrMnO3 superlattices are presented showcasing a new high‐temperature ferromagnetic phase with Curie temperature, TC ≈360 K, caused by electron transfer from the surface of the LaMnO3 donor layer into the neighboring SrMnO3 acceptor layer. As a result, the SrMnO3 (top)/LaMnO3 (bottom) interface shows an enhancement of the magnetization as depth‐profiled by polarized neutron reflectometry. The length scale of charge transfer, λTF ≈2 unit cells, is obtained from in situ growth monitoring by optical ellipsometry, supported by optical simulations, and further confirmed by high resolution electron microscopy and spectroscopy. A model of the inhomogeneous distribution of electron density in LaMnO3/SrMnO3 layers along the growth direction is concluded to account for a complex interplay between ferromagnetic and antiferromagnetic layers in superlattices. |
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Editor |
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Wos |
000535358900008 |
Publication Date |
2019-02-10 |
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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 |
1616301X |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15.621 |
Times cited |
26 |
Open Access |
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Notes |
The authors thank EU FP7 Framework (Project IFOX) and DFG (SFB 1073, TP B04, A02, Z02) for the financial support. J.V., K.M.C and N.G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge ordering). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. The PNR experiment was funded by the Australian Nuclear Science and Technology Organization (proposal number P3985). |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:162108 |
Serial |
5294 |
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| Permanent link to this record |
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Author |
Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J. |
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Title |
Interstitial defects in the van der Waals gap of Bi2Se3 |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) |
Abbreviated Journal |
Acta Crystallogr B |
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Volume |
75 |
Issue |
4 |
Pages |
717-732 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Bi<sub>2</sub>Se<sub>3</sub>is a thermoelectric material and a topological insulator. It is slightly conducting in its bulk due to the presence of defects and by controlling the defects different physical properties can be fine tuned. However, studies of the defects in this material are often contradicting or inconclusive. Here, the defect structure of Bi<sub>2</sub>Se<sub>3</sub>is studied with a combination of techniques: high-resolution scanning transmission electron microscopy (HR-STEM), high-resolution energy-dispersive X-ray (HR-EDX) spectroscopy, precession electron diffraction tomography (PEDT), X-ray diffraction (XRD) and first-principles calculations using density functional theory (DFT). Based on these results, not only the observed defects are discussed, but also the discrepancies in results or possibilities across the techniques. STEM and EDX revealed interstitial defects with mainly Bi character in an octahedral coordination in the van der Waals gap, independent of the applied sample preparation method (focused ion beam milling or cryo-crushing). The inherent character of these defects is supported by their observation in the structure refinement of the EDT data. Moreover, the occupancy probability of the defects determined by EDT is inversely proportional to their corresponding DFT calculated formation energies. STEM also showed the migration of some atoms across and along the van der Waals gap. The kinetic barriers calculated using DFT suggest that some paths are possible at room temperature, while others are most probably beam induced. |
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Wos |
000480512600024 |
Publication Date |
2019-08-01 |
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Series Editor |
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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 |
2052-5206 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.032 |
Times cited |
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Open Access |
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Notes |
University of Antwerp, 31445 ; Acknowledgements We thank Artem M. Abakumov for providing the original Bi2Se3 sample and are also very grateful to Christophe Vandevelde for trying repeatedly to get good single crystal X-ray diffraction data out of each of our failed attempts at making an undeformed single crystal. The computational resources and services used in this work were 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-department EWI. |
Approved |
Most recent IF: 2.032 |
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Call Number |
EMAT @ emat @c:irua:161847 |
Serial |
5295 |
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Author |
Zeng, C.Y.; Cao, S.; Li, Y.Y.; Zhao, Z.X.; Yao, X.Y.; Ma, X.; Zhang, X.P. |
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Title |
A hidden single-stage martensitic transformation from B2 parent phase to B19 ' martensite phase in an aged Ni51Ti49 alloy |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Materials letters |
Abbreviated Journal |
Mater Lett |
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Volume |
253 |
Issue |
253 |
Pages |
99-101 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The aged Ni-rich NiTi shape memory alloys (SMAs) exhibit the multi-stage martensitic transformation (MMT), which has important influences on functional properties and practical applications of the NiTi SMAs. A hidden single-stage martensitic transformation from B2 parent phase to B19' martensite phase is found in an aged Ni51Ti49 alloy, which happens concurrently with a commonly observed two-stage martensitic transformation B2-R-B19' (R: martensite phase) and actually composes one stage of a multi-stage martensitic transformation (MMT) together with the two-stage one. B2-B19' martensitic transformation occurs in the NiTi matrix containing Ni4Ti3 precipitates with relatively large inter-particle space, while B2-R-B19' transformation takes place in the NiTi matrix with Ni4Ti3 precipitates having relatively small inter-particle space. (C) 2019 Elsevier B.V. All rights reserved. |
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Wos |
000482629500025 |
Publication Date |
2019-06-17 |
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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 |
0167-577x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.572 |
Times cited |
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Open Access |
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Notes |
; This work was supported by the Natural Science Foundation of Guangdong Province under Grant Nos. 2018B0303110012 and 2017A030313323, and the National Natural Science Foundation of China under Grant Nos. 51401081 and 51571092. ; |
Approved |
Most recent IF: 2.572 |
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Call Number |
UA @ admin @ c:irua:162764 |
Serial |
5381 |
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Author |
Chizhov, A.; Vasiliev, R.; Rumyantseva, M.; Krylov, I.; Drozdov, K.; Batuk, M.; Hadermann, J.; Abakumov, A.; Gaskov, A. |
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Title |
Light-activated sub-ppm NO2 detection by hybrid ZnO/QD nanomaterials vs. charge localization in core-shell QD |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Frontiers in materials |
Abbreviated Journal |
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Volume |
6 |
Issue |
6 |
Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
New hybrid materials-photosensitized nanocomposites containing nanocrystal heterostructures with spatial charge separation, show high response for practically important sub-ppm level NO2 detection at room temperature. Nanocomposites ZnO/CdSe, ZnO/(CdS@CdSe), and ZnO/(ZnSe@CdS) were obtained by the immobilization of nanocrystals-colloidal quantum dots (QDs), on the matrix of nanocrystalline ZnO. The formation of crystalline core-shell structure of QDs was confirmed by HAADF-STEM coupled with EELS mapping. Optical properties of photosensitizers have been investigated by optical absorption and luminescence spectroscopy combined with spectral dependences of photoconductivity, which proved different charge localization regimes. Photoelectrical and gas sensor properties of nanocomposites have been studied at room temperature under green light (max = 535 nm) illumination in the presence of 0.12-2 ppm NO2 in air. It has been demonstrated that sensitization with type II heterostructure ZnSe@CdS with staggered gap provides the rapid growth of effective photoresponse with the increase in the NO2 concentration in air and the highest sensor sensitivity toward NO2. We believe that the use of core-shell QDs with spatial charge separation opens new possibilities in the development of light-activated gas sensors working without thermal heating. |
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Place of Publication |
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Wos |
000487641600002 |
Publication Date |
2019-09-24 |
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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 |
2296-8016 |
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 |
1 |
Open Access |
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Notes |
; This work was financially supported by RFBR grant No. 1653-76001 (RFBR – ERA.Net FONSENS 096) and in part by a grant from the St. Petersburg State University – Event 3-2018 (id: 26520408). AC acknowledges support from the RFBR grant No. 18-33-01004. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:163776 |
Serial |
5390 |
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| Permanent link to this record |
