Records |
Author |
Yao, X. |
Title |
An advanced TEM study on quantification of Ni4Ti3 precipitates in low temperature aged Ni-Ti shape memory alloy |
Type |
Doctoral thesis |
Year |
2019 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
149 p. |
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:164987 |
Serial |
6284 |
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Author |
Choukroun, D.; Daems, N.; Kenis, T.; Van Everbroeck, T.; Hereijgers, J.; Altantzis, T.; Bals, S.; Cool, P.; Breugelmans, T. |
Title |
Bifunctional nickel-nitrogen-doped-carbon-supported copper electrocatalyst for CO2 reduction |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
Volume |
124 |
Issue |
124 |
Pages |
1369-1381 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
Bifunctionality is a key feature of many industrial catalysts, supported metal clusters and particles in particular, and the development of such catalysts for the CO2 reduction reaction (CO2RR) to hydrocarbons and alcohols is gaining traction in light of recent advancements in the field. Carbon-supported Cu nanoparticles are suitable candidates for integration in the state-of-the-art reaction interfaces, and here, we propose, synthesize, and evaluate a bifunctional Ni–N-doped-C-supported Cu electrocatalyst, in which the support possesses active sites for selective CO2 conversion to CO and Cu nanoparticles catalyze either the direct CO2 or CO reduction to hydrocarbons. In this work, we introduce the scientific rationale behind the concept, its applicability, and the challenges with regard to the catalyst. From the practical aspect, the deposition of Cu nanoparticles onto carbon black and Ni–N–C supports via an ammonia-driven deposition precipitation method is reported and explored in more detail using X-ray diffraction, thermogravimetric analysis, and hydrogen temperature-programmed reduction. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDXS) give further evidence of the presence of Cu-containing nanoparticles on the Ni–N–C supports while revealing an additional relationship between the nanoparticle’s composition and the electrode’s electrocatalytic performance. Compared to the benchmark carbon black-supported Cu catalysts, Ni–N–C-supported Cu delivers up to a 2-fold increase in the partial C2H4 current density at −1.05 VRHE (C1/C2 = 0.67) and a concomitant 10-fold increase of the CO partial current density. The enhanced ethylene production metrics, obtained by virtue of the higher intrinsic activity of the Ni–N–C support, point out toward a synergistic action between the two catalytic functionalities. |
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Wos |
000508467700015 |
Publication Date |
2020-01-07 |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
1932-7447; 1932-7455 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.7 |
Times cited |
24 |
Open Access |
OpenAccess |
Notes |
; N.D. acknowledges sponsoring from the research foundation of Flanders (FWO) in the frame of a postdoctoral grant (12Y3919N N.D.). J.H. greatly acknowledges the Research Foundation Flanders (FWO) for support through a postdoctoral fellowship (28761). T.V.E. and P.C. acknowledge financial support from the EU-Partial-PGMs project (H2020NMP-686086). The authors also acknowledge financial support from the university research fund (BOF-GOA PS ID No. 33928). ; |
Approved |
Most recent IF: 3.7; 2020 IF: 4.536 |
Call Number |
UA @ admin @ c:irua:165326 |
Serial |
6286 |
Permanent link to this record |
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Author |
Callaert, C. |
Title |
Characterization of defects, modulations and surface layers in topological insulators and structurally related compounds |
Type |
Doctoral thesis |
Year |
2020 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
180 p. |
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:165867 |
Serial |
6288 |
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Author |
Wang, Z.; Wang, Y.B.; Yin, J.; Tovari, E.; Yang, Y.; Lin, L.; Holwill, M.; Birkbeck, J.; Perello, D.J.; Xu, S.; Zultak, J.; Gorbachev, R.V.; Kretinin, A.V.; Taniguchi, T.; Watanabe, K.; Morozov, S.V.; Andelkovic, M.; Milovanović, S.P.; Covaci, L.; Peeters, F.M.; Mishchenko, A.; Geim, A.K.; Novoselov, K.S.; Fal'ko, V.I.; Knothe, A.; Woods, C.R. |
Title |
Composite super-moiré lattices in double-aligned graphene heterostructures = Composite super-moire lattices in double-aligned graphene heterostructures |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Science Advances |
Abbreviated Journal |
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Volume |
5 |
Issue |
12 |
Pages |
eaay8897 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
When two-dimensional (2D) atomic crystals are brought into close proximity to form a van der Waals heterostructure, neighbouring crystals may influence each other's properties. Of particular interest is when the two crystals closely match and a moire pattern forms, resulting in modified electronic and excitonic spectra, crystal reconstruction, and more. Thus, moire patterns are a viable tool for controlling the properties of 2D materials. However, the difference in periodicity of the two crystals limits the reconstruction and, thus, is a barrier to the low-energy regime. Here, we present a route to spectrum reconstruction at all energies. By using graphene which is aligned to two hexagonal boron nitride layers, one can make electrons scatter in the differential moire pattern which results in spectral changes at arbitrarily low energies. Further, we demonstrate that the strength of this potential relies crucially on the atomic reconstruction of graphene within the differential moire super cell. |
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Place of Publication |
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Wos |
000505069600089 |
Publication Date |
2019-12-21 |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
2375-2548 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
71 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:165754 |
Serial |
6289 |
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Author |
Sandfeld, S.; Samaee, V.; Idrissi, H.; Groten, J.; Pardoen, T.; Schwaiger, R.; Schryvers, D. |
Title |
Datasets for the analysis of dislocations at grain boundaries and during vein formation in cyclically deformed Ni micropillars |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Data in Brief |
Abbreviated Journal |
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Volume |
27 |
Issue |
27 |
Pages |
104724 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The dataset together with the corresponding Python scripts and Jupyter notebooks presented in this article are supplementary data for the work presented in Samaee et al., 2019 [1]. The data itself consists of two parts: the simulation data that was used in [1] to analyze the effect of a particular grain boundary on curved dislocations and the precession electron diffraction (PED) strain maps together with post-processed data for analyzing details of the observed dislocation vein structures. Additionally, the complete stress tensor components, which are not shown in [1], have also been included. The data sets are accompanied by Python code explaining the file formats and showing how to post-process the data. (c) 2019 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). |
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Wos |
000501988200181 |
Publication Date |
2019-11-03 |
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Series Issue |
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Edition |
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ISSN |
2352-3409 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:165092 |
Serial |
6292 |
Permanent link to this record |
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Author |
Smith, J.D.; Bladt, E.; Burkhart, J.A.C.; Winckelmans, N.; Koczkur, K.M.; Ashberry, H.M.; Bals, S.; Skrabalak, S.E. |
Title |
Defect-directed growth of symmetrically branched metal nanocrystals |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Angewandte Chemie-International Edition |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
59 |
Issue |
59 |
Pages |
943-950 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Branched plasmonic nanocrystals (NCs) have attracted much attention due to electric field enhancements at their tips. Seeded growth provides routes to NCs with defined branching patterns and, in turn, near-field distributions with defined symmetries. Here, a systematic analysis was undertaken in which seeds containing different distributions of planar defects were used to grow branched NCs in order to understand how their distributions direct the branching. Characterization of the products by multimode electron tomography and analysis of the NC morphologies at different overgrowth stages indicate that the branching patterns are directed by the seed defects, with the emergence of branches from the seed faces consistent with minimizing volumetric strain energy at the expense of surface energy. These results contrast with growth of branched NCs from single-crystalline seeds and provide a new platform for the synthesis of symmetrically branched plasmonic NCs. |
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 |
000498760200001 |
Publication Date |
2019-11-13 |
Series Editor |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
16.6 |
Times cited |
23 |
Open Access |
OpenAccess |
Notes |
; The authors thank Samantha Harvey for her initial observations of branched structures, Alexander Chen for his help with SAED, the staff of the Nanoscale Characterization Facility (Dr. Yi Yi), Electron Microscopy Center (Dr. David Morgan and Dr. Barry Stein), and Molecular Structure Center at Indiana University. J.S. recognizes a fellowship provided by the Indiana Space Grant Consortium. E.B. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). This project has received funding to S.E.S. from the U.S. National Science Foundation (award numbers: 1602476 and 1904499) and Research Corporation for Scientific Advancement (2017 Frontiers in Research Excellence and Discovery Award) as well as to S.B. from the European Union's Horizon 2020 research and innovation program under grant agreement No 731019 (EUSMI) and No 815128 (REALNANO). ; sygma |
Approved |
Most recent IF: 16.6; 2020 IF: 11.994 |
Call Number |
UA @ admin @ c:irua:165124 |
Serial |
6293 |
Permanent link to this record |
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Author |
Weng, Y.; Ding, L.; Zhang, Z.; Jia, Z.; Wen, B.; Liu, Y.; Muraishi, S.; Li, Y.; Liu, Q. |
Title |
Effect of Ag addition on the precipitation evolution and interfacial segregation for Al-Mg-Si alloy |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
Volume |
180 |
Issue |
180 |
Pages |
301-316 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The effect of Ag addition on the precipitation evolution and interfacial segregation for Al-Mg-Si alloys was systematically investigated by atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), atom probe tomography (APT) and density functional theory (DFT) calculation. At the early aging stage, Ag atoms could enter clusters and refine the distribution of these clusters. Then, Ag atoms preferentially segregate at the GP zone/alpha-Al and beta ''/alpha-Al interfaces at the peak aging stage by the replacement of Al atoms in FCC matrix. With prolonging aging time, Ag atoms generally incorporate into the interior of beta '' precipitate, facilitating the formation of QP lattice (a hexagonal network of Si atomic columns) and the local symmetry substructures, Ag sub-unit (1) and Ag sub-unit (2). At the over-aged stage, the Ag sub-unit (1) and Ag sub-unit (2) could transform to the beta'(Ag) (i.e. beta'(Ag1) and beta'(Ag2).) and Q'(Ag) unit cells, respectively. All the precipitates at the over-aging stage have a composite and disordered structure due to the coexistence of different unit cells (beta'(Ag1), beta'(Ag2), Q'(Ag) and beta') and the non-periodic arrangement of Ag atoms within the precipitate. In the equilibrium stage, the incorporated Ag atoms in the precipitates release into the alpha-Al matrix as solute atoms or form Ag particles. In general, Ag atoms undergo a process of “segregate at the precipitate/matrix interface -> incorporate into the interior of precipitate -> release into the alpha-Al matrix” during the precipitation for Al-Mg-Si-Ag alloys. Besides, Ag segregation is found at the interfaces of almost all metastable phases (including GP zone, beta '', beta'/beta'(Ag) phase) in Al-Mg-Si-Ag alloys. The Ag segregation at the beta'/alpha-Al interface could increase the length/diameter ratio of beta' phase and thus promote the additional strengthening potential of these alloys. These findings provide a new route for precipitation hardening by promoting the nucleation and morphology evolution of precipitates. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Place of Publication |
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Wos |
000495519100028 |
Publication Date |
2019-09-12 |
Series Editor |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
1359-6454 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.301 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 5.301 |
Call Number |
UA @ admin @ c:irua:164641 |
Serial |
6295 |
Permanent link to this record |
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Author |
Susi, T.; Madsen, J.; Ludacka, U.; Mortensen, J.J.; Pennycook, T.J.; Lee, Z.; Kotakoski, J.; Kaiser, U.; Meyer, J.C. |
Title |
Efficient first principles simulation of electron scattering factors for transmission electron microscopy |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
197 |
Issue |
197 |
Pages |
16-22 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Electron microscopy is a powerful tool for studying the properties of materials down to their atomic structure. In many cases, the quantitative interpretation of images requires simulations based on atomistic structure models. These typically use the independent atom approximation that neglects bonding effects, which may, however, be measurable and of physical interest. Since all electrons and the nuclear cores contribute to the scattering potential, simulations that go beyond this approximation have relied on computationally highly demanding all-electron calculations. Here, we describe a new method to generate ab initio electrostatic potentials when describing the core electrons by projector functions. Combined with an interface to quantitative image simulations, this implementation enables an easy and fast means to model electron scattering. We compare simulated transmission electron microscopy images and diffraction patterns to experimental data, showing an accuracy equivalent to earlier all-electron calculations at a much lower computational cost. |
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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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Wos |
000456311700003 |
Publication Date |
2018-11-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
0304-3991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843 |
Call Number |
UA @ admin @ c:irua:165938 |
Serial |
6296 |
Permanent link to this record |
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Author |
Spreitzer, M.; Klement, D.; Egoavil, R.; Verbeeck, J.; Kovac, J.; Zaloznik, A.; Koster, G.; Van Tendeloo, G.; Suvorov, D.; Rijnders, G. |
Title |
Growth mechanism of epitaxial SrTiO3 on a (1 x 2) + (2 x 1) reconstructed Sr(1/2 ML)/Si(001) surface |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Materials Chemistry C |
Abbreviated Journal |
J Mater Chem C |
Volume |
8 |
Issue |
2 |
Pages |
518-527 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Sub-monolayer control over the growth at silicon-oxide interfaces is a prerequisite for epitaxial integration of complex oxides with the Si platform, enriching it with a variety of functionalities. However, the control over this integration is hindered by the intense reaction of the constituents. The most suitable buffer material for Si passivation is metallic strontium. When it is overgrown with a layer of SrTiO3 (STO) it can serve as a pseudo-substrate for the integration with functional oxides. In our study we determined a mechanism for epitaxial integration of STO with a (1 x 2) + (2 x 1) reconstructed Sr(1/2 ML)/Si(001) surface using all-pulsed laser deposition (PLD) technology. A detailed analysis of the initial deposition parameters was performed, which enabled us to develop a complete protocol for integration, taking into account the peculiarities of the PLD growth, STO critical thickness, and process thermal budget, in order to kinetically trap the reaction between STO and Si and thus to minimize the thickness of the interface layer. The as-prepared oxide layer exhibits STO(001)8Si(001) out-of-plane and STO[110]8Si[100] in-plane orientation and together with recent advances in large-scale PLD tools these results represent a new technological solution for the implementation of oxide electronics on demand. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000506852400036 |
Publication Date |
2019-10-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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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 |
Impact Factor |
6.4 |
Times cited |
12 |
Open Access |
OpenAccess |
Notes |
; The research was financially supported by the Slovenian Research Agency (Project No. P2-0091, J2-9237) and Ministry of Education, Science and Sport of the Republic of Slovenia (SIOX projects). This work was also funded by the European Union Council under the 7th Framework Program grant no. NMP3-LA-2010-246102 IFOX. J. V. and G. V. T. acknowledge funding from the Fund for Scientific Research Flanders under project no. G.0044.13N. ; |
Approved |
Most recent IF: 6.4; 2020 IF: 5.256 |
Call Number |
UA @ admin @ c:irua:165672 |
Serial |
6298 |
Permanent link to this record |
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Author |
Pennycook, T.J.; Martinez, G.T.; Nellist, P.D.; Meyer, J.C. |
Title |
High dose efficiency atomic resolution imaging via electron ptychography |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
196 |
Issue |
196 |
Pages |
131-135 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Radiation damage places a fundamental limitation on the ability of microscopy to resolve many types of materials at high resolution. Here we evaluate the dose efficiency of phase contrast imaging with electron ptychography. The method is found to be far more resilient to temporal incoherence than conventional and spherical aberration optimized phase contrast imaging, resulting in significantly greater clarity at a given dose. This robustness is explained by the presence of achromatic lines in the four dimensional ptychographic dataset. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Wos |
000451180800018 |
Publication Date |
2018-10-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
0304-3991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843 |
Call Number |
UA @ admin @ c:irua:165939 |
Serial |
6301 |
Permanent link to this record |
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Author |
Wu, Y.; Chen, G.; Yu, J.; Wang, D.; Ma, C.; Li, C.; Pennycook, S.J.; Yan, Y.; Wei, S.-H. |
Title |
Hole-induced spontaneous mutual annihilation of dislocation pairs |
Type |
A1 Journal article |
Year |
2019 |
Publication |
The journal of physical chemistry letters |
Abbreviated Journal |
J Phys Chem Lett |
Volume |
10 |
Issue |
23 |
Pages |
7421-7425 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Dislocations are always observed during crystal growth, and it is usually desirable to reduce the dislocation density in high-quality crystals. Here, the annihilation process of the 30 degrees Shockley partial dislocation pairs in CdTe is studied by first-principles calculations. We found that the dislocations can glide relatively easily due to the weak local bonding. Our systematic study of the slipping mechanism of the dislocations suggests that the energy barrier for the annihilation process is low. Band structure calculations reveal that the band bending caused by the charge transfer between the two dislocation cores depends on the core-core distance. A simple linear model is proposed to describe the mechanism of formation of the dislocation pair. More importantly, we demonstrate that hole injection can affect the core structure, increase the mobility, and eventually trigger a spontaneous mutual annihilation, which could be employed as a possible facile way to reduce the dislocation density. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000501622700017 |
Publication Date |
2019-11-17 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
1948-7185 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
9.353 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 9.353 |
Call Number |
UA @ admin @ c:irua:165068 |
Serial |
6302 |
Permanent link to this record |
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Author |
Morozov, V.A.; Posokhova, S.M.; Deyneko, D., V; Savina, A.A.; Morozov, A., V; Tyablikov, O.A.; Redkin, B.S.; Spassky, D.A.; Hadermann, J.; Lazoryak, B., I |
Title |
Influence of annealing conditions on the structure and luminescence properties of KGd1-xEux(MoO4)2(0\leq x\leq1) |
Type |
A1 Journal article |
Year |
2019 |
Publication |
CrystEngComm |
Abbreviated Journal |
Crystengcomm |
Volume |
21 |
Issue |
42 |
Pages |
6460-6471 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This study describes the influence of annealing temperature on the structure and luminescence properties of KGd1-xEux(MoO4)(2) (0 <= x <= 1). Compounds with the general formula (A ', A '')(n)[(W, Mo)O-4](m) are investigated as luminescent materials for photonic applications such as phosphor-converted LEDs (light-emitting diodes). Herein, the KGd0.8Eu0.2(MoO4)(2) light-rose crystal was grown by the Czochralski technique. Moreover, three polymorphs of KGd1-xEux(MoO4)(2) were present in the 923-1223 K range of annealing temperatures under ambient pressure: a triclinic alpha-phase, a disproportionately modulated monoclinic beta-phase and an orthorhombic gamma-phase with a KY(MoO4)(2)-type structure. The different behaviors of KGd(MoO4)(2) and KEu(MoO4)(2) were revealed by DSC studies. The number and the character of phase transitions for KGd1-xEux(MoO4)(2) depended on the elemental composition. The formation of a continuous range of solid solutions with the triclinic alpha-KEu(MoO4)(2)-type structure and ordering of K+ and Eu3+/Gd3+ cations were observed only for alpha-KGd1-xEux(MoO4)(2) (0 <= x <= 1) prepared at 923 K. The structures of gamma-KGd1-xEux(MoO4)(2) (x = 0 and 0.2) were studied using electron diffraction and refined using the powder X-ray diffraction data. The luminescence properties of KGd1-xEux(MoO4)(2) prepared at different annealing temperatures were studied and related to their different structures. The maxima of the D-5(0) -> F-7(2) integral emission intensities were found under excitation at lambda(ex) = 300 nm and lambda(ex) = 395 nm for triclinic scheelite-type alpha-KGd0.6Eu0.4(MoO4)(2) and monoclinic scheelite-type beta-KGd0.4Eu0.6(MoO4)(2) prepared at 1173 K, respectively. The latter shows the brightest red light emission among the KGd1-xEux(MoO4)(2) phosphors. The maximum and integral emission intensity of beta-KGd0.4Eu0.6(MoO4)(2) in the D-5(0) -> F-7(2) transition region is similar to 20% higher than that of the commercially used red phosphor Gd2O2S:Eu3+. Thus, beta-KGd0.4Eu0.6(MoO4)(2) is very attractive for application as a near-UV convertible red-emitting phosphor for LEDs. |
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 |
000493072200015 |
Publication Date |
2019-09-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
1466-8033 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.474 |
Times cited |
|
Open Access |
|
Notes |
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Approved |
Most recent IF: 3.474 |
Call Number |
UA @ admin @ c:irua:164603 |
Serial |
6304 |
Permanent link to this record |
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Author |
Pourbabak, S. |
Title |
Influence of nano and microstructural features and defects in finegrained NiTi on the thermal and mechanical reversibility of the martensitic transformation |
Type |
Doctoral thesis |
Year |
2020 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
166 p. |
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
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Publication Date |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:165919 |
Serial |
6305 |
Permanent link to this record |
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Author |
Du, K.; Zhang, M.; Dai, C.; Zhou, Z.N.; Xie, Y.W.; Ren, Z.H.; Tian, H.; Chen, L.Q.; Van Tendeloo, G.; Zhang, Z. |
Title |
Manipulating topological transformations of polar structures through real-time observation of the dynamic polarization evolution |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
10 |
Issue |
10 |
Pages |
4864 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Topological structures based on controllable ferroelectric or ferromagnetic domain configurations offer the opportunity to develop microelectronic devices such as high-density memories. Despite the increasing experimental and theoretical insights into various domain structures (such as polar spirals, polar wave, polar vortex) over the past decade, manipulating the topological transformations of polar structures and comprehensively understanding its underlying mechanism remains lacking. By conducting an in-situ non-contact bias technique, here we systematically investigate the real-time topological transformations of polar structures in PbTiO3/SrTiO3 multilayers at an atomic level. The procedure of vortex pair splitting and the transformation from polar vortex to polar wave and out-of-plane polarization are observed step by step. Furthermore, the redistribution of charge in various topological structures has been demonstrated under an external bias. This provides new insights for the symbiosis of polar and charge and offers an opportunity for a new generation of microelectronic devices. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000492835100002 |
Publication Date |
2019-10-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
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Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:164681 |
Serial |
6307 |
Permanent link to this record |
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Author |
Lumbeeck, G. |
Title |
Mechanisms of nano-plasticity in as-deposited and hydrided nanocrystalline Pd and Ni thin films |
Type |
Doctoral thesis |
Year |
2019 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
|
Pages |
130 p. |
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
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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 ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
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Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:164918 |
Serial |
6309 |
Permanent link to this record |
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Author |
Sirotina, A.P.; Callaert, C.; Volykhov, A.A.; Frolov, A.S.; Sanchez-Barriga, J.; Knop-Gericke, A.; Hadermann, J.; Yashina, L.V. |
Title |
Mechanistic studies of gas reactions with multicomponent solids : what can we learn by combining NAP XPS and atomic resolution STEM/EDX? |
Type |
A1 Journal article |
Year |
2019 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
123 |
Issue |
43 |
Pages |
26201-26210 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Rapid development of experimental techniques has enabled real time studies of solid gas reactions at the level reaching the atomic scale. In the present paper, we focus on a combination of atomic resolution STEM/EDX, which visualizes the reaction zone, and near ambient pressure (NAP) XPS, which collects information for a surface layer of variable thickness under reaction conditions. We compare the behavior of two affined topological insulators, Bi2Te3 and Sb2Te3. We used a simple reaction with molecular oxygen occurring at 298 K, which is of practical importance to avoid material degradation. Despite certain limitations, a combination of in situ XPS and ex situ cross-sectional STEM/EDX allowed us to obtain a self-consistent picture of the solid gas reaction mechanism for oxidation of Sb2Te3 and Bi2Te3 crystals, which includes component redistribution between the oxide and the subsurface layer and Te segregation with formation of a thin ordered layer at the interface. The process is multistep in case of both compounds. At the very beginning of the oxidation process the reactivity is determined by the energy benefit of the corresponding element oxygen bond formation. Further in the oxidation process, the behavior of these two compounds becomes similar and features component redistribution between the oxide and the subsurface layer. |
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 |
000493865700019 |
Publication Date |
2019-10-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
|
ISSN |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
|
Open Access |
|
Notes |
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Approved |
Most recent IF: 4.536 |
Call Number |
UA @ admin @ c:irua:164664 |
Serial |
6310 |
Permanent link to this record |
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Author |
Daems, N.; De Mot, B.; Choukroun, D.; Van Daele, K.; Li, C.; Hubin, A.; Bals, S.; Hereijgers, J.; Breugelmans, T. |
Title |
Nickel-containing N-doped carbon as effective electrocatalysts for the reduction of CO2 to CO in a continuous-flow electrolyzer |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Sustainable energy & fuels |
Abbreviated Journal |
|
Volume |
4 |
Issue |
4 |
Pages |
1296-1311 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
Nickel-containing N-doped carbons were synthesized for the electrochemical reduction of CO2 to CO, which is a promising approach to reduce the atmospheric CO2 levels and its negative impact on the environment. Unfortunately, poor performance (activity, selectivity and/or stability) is still a major hurdle for the economical implementation of this type of materials. The electrocatalysts were prepared through an easily up-scalable and easily tunable method based on the pyrolysis of Ni-containing N-doped carbons. Ni–N–AC–B1 synthesized with a high relative amount of nitrogen and nickel with respect to carbon, was identified as the most promising candidate for this reaction based on its partial CO current density (4.2 mA cm−2), its overpotential (0.57 V) and its faradaic efficiency to CO (>99%). This results in unprecedented values for the current density per g active sites (690 A g−1 active sites). Combined with its decent stability and its high performance in an actual electrolyzer setup, this makes it a promising candidate for the electrochemical reduction of CO2 to CO on a larger scale. Finally, the evaluation of this kind of material in a flow-cell setup has been limited and to the best of our knowledge never included an evaluation of several crucial parameters (e.g. electrolyte type, anode composition and membrane type) and is an essential investigation in the move towards up-scaling and ultimately industrial application of this technique. This study resulted in an optimal cell configuration, consisting of Pt as an anode, Fumatech® as the membrane and 1 M KHCO3 and 2 M KOH as catholyte and anolyte, respectively. In conclusion, this research offers a unique combination of electrocatalyst development and reactor optimization. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000518690900030 |
Publication Date |
2019-12-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
14 |
Open Access |
OpenAccess |
Notes |
; The authors acknowledge sponsoring from the research foundation of Flanders (FWO) in the frame of a post-doctoral grant (12Y3919N – ND). J. Hereijgers was supported through a postdoctoral fellowship (28761) of the Research Foundation Flanders (FWO). This project was co-funded by the Interreg 2 Seas-Program 2014-2020, co-.nanced by the European Fund for Regional Development in the frame of subsidiary contract nr 2S03-019. This work was further performed in the framework of the Catalisti cluster SBO project CO2PERATE (“All renewable CCU based on formic acid integrated in an industrial microgrid”), with the.nancial support of VLAIO (Flemish Agency for Innovation and Entrepreneurship). This project.nally received funding from the European Research Council (ERC Consolidator Grant 815128, REALNANO). We thank Karen Leyssens for helping with the N<INF>2</INF> physisorption measurements and Kitty Baert (VUB) for analyzing the samples with XPS and Raman. ; sygma |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:165482 |
Serial |
6311 |
Permanent link to this record |
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Author |
Jin, B.; Liang, F.; Hu, Z.-Y.; Wei, P.; Liu, K.; Hu, X.; Van Tendeloo, G.; Lin, Z.; Li, H.; Zhou, X.; Xiong, Q.; Zhai, T. |
Title |
Nonlayered CdSe flakes homojunctions |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
30 |
Issue |
30 |
Pages |
1908902 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
2D homojunctions have stimulated extensive attention because of their perfect thermal and lattice matches, as well as their tunable band structures in 2D morphology, which provide fascinating opportunities for novel electronics and optoelectronics. Recently, 2D nonlayered materials have attracted the attention of researchers owing to their superior functional applications and diverse portfolio of the 2D family. Therefore, 2D nonlayered homojunctions would open the door to a rich spectrum of exotic 2D materials. However, they are not investigated due to their extremely difficult synthesis methods. Herein, nonlayered CdSe flakes homojunctions are obtained via self-limited growth with InCl3 as a passivation agent. Interestingly, two pieces of vertical wurtzite-zinc blende (WZ-ZB) homojunctions epitaxially integrate into WZ/ZB lateral junctions. These homojunctions show a divergent second-harmonic generation intensity, strongly correlated to the multiple twinned ZB phase, as identified by aberration-corrected scanning transmission electron microscopy and theoretical calculations. Impressively, the photodetector based on this WZ/ZB CdSe homojunction shows excellent performances, integrating a high photoswitching ratio (3.4 x 10(5)) and photoresponsivity (3.7 x 10(3) A W-1), suggesting promising potential for applications in electronics and optoelectronics. |
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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 |
000508624800001 |
Publication Date |
2020-01-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
|
ISSN |
1616-301x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19 |
Times cited |
8 |
Open Access |
Not_Open_Access |
Notes |
; This work was supported by the National Natural Science Foundation of China (Grant Nos. 21825103, 51727809, and 51802103), the Hubei Provincial Natural Science Foundation of China (2019CFA002), and the Fundamental Research Funds for the Central Universities (HUST: 2019kfyXMBZ018; WUT: 2019III012GX). Here the authors also thank the support from Analytical and Testing Center in HUST and the State Key Laboratory of Silicate Materials for Architectures in WUT. ; |
Approved |
Most recent IF: 19; 2020 IF: 12.124 |
Call Number |
UA @ admin @ c:irua:165654 |
Serial |
6314 |
Permanent link to this record |
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Author |
Wang, J.; Nguyen, M.D.; Gauquelin, N.; Verbeeck, J.; Do, M.T.; Koster, G.; Rijnders, G.; Houwman, E. |
Title |
On the importance of the work function and electron carrier density of oxide electrodes for the functional properties of ferroelectric capacitors |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physica Status Solidi-Rapid Research Letters |
Abbreviated Journal |
Phys Status Solidi-R |
Volume |
14 |
Issue |
14 |
Pages |
1900520 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
It is important to understand the effect of the interfaces between the oxide electrode layers and the ferroelectric layer on the polarization response for optimizing the device performance of all-oxide ferroelectric devices. Herein, the effects of the oxide La0.07Ba0.93SnO3 (LBSO) as an electrode material in an PbZr0.52Ti0.48O3 (PZT) ferroelectric capacitor are compared with those of the more commonly used SrRuO3 (SRO) electrode. SRO (top)/PZT/SRO (bottom), SRO/PZT/LBSO, and SRO/PZT/2 nm SRO/LBSO devices are fabricated. Only marginal differences in crystalline properties, determined by X-ray diffraction and scanning transmission electron microscopy, are found. High-quality polarization loops are obtained, but with a much larger coercive field for the SRO/PZT/LBSO device. In contrast to the SRO/PZT/SRO device, the polarization decreases strongly with increasing field cycling. This fatigue problem can be remedied by inserting a 2 nm SRO layer between PZT and LBSO. It is argued that strongly increased charge injection into the PZT occurs at the bottom interface, because of the low PZT/LBSO interfacial barrier and the much lower carrier density in LBSO, as compared with that in SRO, causing a low dielectric constant, depleted layer in LBSO. The charge injection creates a trapped space charge in the PZT, causing the difference in fatigue behavior. |
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 |
000506195600001 |
Publication Date |
2019-12-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
1862-6254 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.8 |
Times cited |
6 |
Open Access |
OpenAccess |
Notes |
; This work was supported by Nederlandse Organisatie voor Wetenschappelijk Onderzoek through grant no.13HTSM01. ; |
Approved |
Most recent IF: 2.8; 2020 IF: 3.032 |
Call Number |
UA @ admin @ c:irua:165681 |
Serial |
6316 |
Permanent link to this record |
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|
Author |
Guzzinati, G.; Béché, A.; McGrouther, D.; Verbeeck, J. |
Title |
Prospects for out-of-plane magnetic field measurements through interference of electron vortex modes in the TEM |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal of optics |
Abbreviated Journal |
J Optics-Uk |
Volume |
21 |
Issue |
12 |
Pages |
124002 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Magnetic field mapping in transmission electron microscopy is commonplace, but all conventional methods provide only a projection of the components of the magnetic induction perpendicular to the electron trajectory. Recent experimental advances with electron vortices have shown that it is possible to map the out of plane magnetic induction in a TEM setup via interferometry with a specifically prepared electron vortex state carrying high orbital angular momentum (OAM). The method relies on the Aharonov?Bohm phase shift that the electron undergoes when going through a longitudinal field. Here we show how the same effect naturally occurs for any electron wave function, which can always be described as a superposition of OAM modes. This leads to a clear connection between the occurrence of high-OAM partial waves and the amount of azimuthal rotation in the far field angular distribution of the beam. We show that out of plane magnetic field measurement can thus be obtained with a much simpler setup consisting of a ring-like aperture with azimuthal spokes. We demonstrate the experimental setup and explore the achievable sensitivity of the magnetic field measurement. |
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 |
000499367800001 |
Publication Date |
2019-10-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
2040-8978 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.741 |
Times cited |
3 |
Open Access |
|
Notes |
The authors thank V Grillo and T Harvey for interesting and fruitful discussion. GG acknowledges support from a postdoctoral fellow-ship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. AB acknowledges funding from FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy'). DM gratefully acknowledges funding of the FEBID capability through joint funding by University of Glasgow & EPSRC through a Strategic Equipment Grant (EP/P001483/1). |
Approved |
Most recent IF: 1.741 |
Call Number |
UA @ admin @ c:irua:165116 |
Serial |
6319 |
Permanent link to this record |
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Author |
Leuthner, G.T.; Hummel, S.; Mangler, C.; Pennycook, T.J.; Susi, T.; Meyer, J.C.; Kotakoski, J. |
Title |
Scanning transmission electron microscopy under controlled low-pressure atmospheres |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
203 |
Issue |
203 |
Pages |
76-81 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Transmission electron microscopy (TEM) is carried out in vacuum to minimize the interaction of the imaging electrons with gas molecules while passing through the microscope column. Nevertheless, in typical devices, the pressure remains at 10(-7) mbar or above, providing a large number of gas molecules for the electron beam to crack, which can lead to structural changes in the sample. Here, we describe experiments carried out in a modified scanning TEM (STEM) instrument, based on the Nion UltraSTEM 100. In this instrument, the base pressure at the sample is around 2 x 10(-10 )mbar, and can be varied up to 10(-6) mbar through introduction of gases directly into the objective area while maintaining atomic resolution imaging conditions. We show that air leaked into the microscope column during the experiment is efficient in cleaning graphene samples from contamination, but ineffective in damaging the pristine lattice. Our experiments also show that exposure to O(2 )and H2O lead to a similar result, oxygen providing an etching effect nearly twice as efficient as water, presumably due to the two 0 atoms per molecule. H(2 )and N-2 environments have no influence on etching. These results show that the residual gas environment in typical TEM instruments can have a large influence on the observations, and show that chemical etching of carbon-based structures can be effectively carried out with oxygen. |
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 |
000465021000010 |
Publication Date |
2019-02-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.843 |
Call Number |
UA @ admin @ c:irua:165937 |
Serial |
6321 |
Permanent link to this record |
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Author |
Hinterding, S.O.M.; Berends, A.C.; Kurttepeli, M.; Moret, M.-E.; Meeldijk, J.D.; Bals, S.; van der Stam, W.; de Donega, C.M. |
Title |
Tailoring Cu+ for Ga3+ cation exchange in Cu2-xS and CuInS2 nanocrystals by controlling the Ga precursor chemistry |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
13 |
Issue |
13 |
Pages |
12880-12893 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Nanoscale cation exchange (CE) has resulted in colloidal nanomaterials that are unattainable by direct synthesis methods. Aliovalent CE is complex and synthetically challenging because the exchange of an unequal number of host and guest cations is required to maintain charge balance. An approach to control aliovalent CE reactions is the use of a single reactant to both supply the guest cation and extract the host cation. Here, we study the application of GaCl3-L complexes [L = trioctylphosphine (TOP), triphenylphosphite (TPP), diphenylphosphine (DPP)] as reactants in the exchange of Cu+ for Ga3+ in Cu2-xS nanocrystals. We find that noncomplexed GaCl3 etches the nanocrystals by S2- extraction, whereas GaCl3-TOP is unreactive. Successful exchange of Cu+ for Ga3+ is only possible when GaCl3 is complexed with either TPP or DPP. This is attributed to the pivotal role of the Cu2-xS-GaCl3-L activated complex that forms at the surface of the nanocrystal at the onset of the CE reaction, which must be such that simultaneous Ga3+ insertion and Cu+ extraction can occur. This requisite is only met if GaCl3 is bound to a phosphine ligand, with a moderate bond strength, to allow facile dissociation of the complex at the nanocrystal surface. The general validity of this mechanism is demonstrated by using GaCl3-DPP to convert CuInS2 into (Cu,Ga,In)S-2 nanocrystals, which increases the photoluminescence quantum yield 10 -fold, while blue -shifting the photoluminescence into the NIR biological window. This highlights the general applicability of the mechanistic insights provided by our work. |
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 |
000500650000061 |
Publication Date |
2019-10-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
|
ISSN |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
27 |
Open Access |
OpenAccess |
Notes |
; S.O.M.H., W.v.d.S., A.C.B., and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under Grant Nos. ECHO.712.012.0001 and ECHO.712.014.001. S.B. acknowledges financial support from the European Research Council (ERC Consolidator Grant No. 815128-REALNANO). S.O.M.H. is supported by The Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation Programme funded by the Ministry of Education, Culture and Science of the government of The Netherlands. DFT calculations were carried out on the Dutch national e-infrastructure with the support of SURF Cooperative. This work was sponsored by NWO Physical Sciences for the use of supercomputer facilities. The authors thank Jessi van der Hoeven for EDS and TEM measurements. ; sygma |
Approved |
Most recent IF: 13.942 |
Call Number |
UA @ admin @ c:irua:165149 |
Serial |
6324 |
Permanent link to this record |
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Author |
Tran Phong Le, P.; Hofhuis, K.; Rana, A.; Huijben, M.; Hilgenkamp, H.; Rijnders, G.A.J.H.M.; ten Elshof, J.E.; Koster, G.; Gauquelin, N.; Lumbeeck, G.; Schuessler-Langeheine, C.; Popescu, H.; Fortuna, F.; Smit, S.; Verbeek, X.H.; Araizi-Kanoutas, G.; Mishra, S.; Vaskivskyi, I.; Duerr, H.A.; Golden, M.S. |
Title |
Tailoring vanadium dioxide film orientation using nanosheets : a combined microscopy, diffraction, transport, and soft X-ray in transmission study |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
30 |
Issue |
1 |
Pages |
1900028 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Vanadium dioxide (VO2) is a much-discussed material for oxide electronics and neuromorphic computing applications. Here, heteroepitaxy of VO2 is realized on top of oxide nanosheets that cover either the amorphous silicon dioxide surfaces of Si substrates or X-ray transparent silicon nitride membranes. The out-of-plane orientation of the VO2 thin films is controlled at will between (011)(M1)/(110)(R) and (-402)(M1)/(002)(R) by coating the bulk substrates with Ti0.87O2 and NbWO6 nanosheets, respectively, prior to VO2 growth. Temperature-dependent X-ray diffraction and automated crystal orientation mapping in microprobe transmission electron microscope mode (ACOM-TEM) characterize the high phase purity, the crystallographic and orientational properties of the VO2 films. Transport measurements and soft X-ray absorption in transmission are used to probe the VO2 metal-insulator transition, showing results of a quality equal to those from epitaxial films on bulk single-crystal substrates. Successful local manipulation of two different VO2 orientations on a single substrate is demonstrated using VO2 grown on lithographically patterned lines of Ti0.87O2 and NbWO6 nanosheets investigated by electron backscatter diffraction. Finally, the excellent suitability of these nanosheet-templated VO2 films for advanced lensless imaging of the metal-insulator transition using coherent soft X-rays is discussed. |
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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 |
000505545800010 |
Publication Date |
2019-10-31 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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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 |
Impact Factor |
19 |
Times cited |
1 |
Open Access |
OpenAccess |
Notes |
P.T.P.L. and K.H. contributed equally to this work. The authors thank Mark A. Smithers for performing high-resolution scanning electron microscopy and electron backscattering diffraction. The authors also thank Dr. Nicolas Jaouen for his contribution to the soft X-ray imaging experiments. This work is part of the DESCO research program of the Foundation for Fundamental Research on Matter (FOM), which is part of the Netherlands Organisation for Scientific Research (NWO). P.T.P.L. acknowledges the NWO/CW ECHO grant ECHO.15.CM2.043. N.G. acknowledges funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and the FLAG-ERA JTC 2017 project GRAPH-EYE. G.L. acknowledges financial support from the Flemish Research Fund (FWO) under project G.0365.15N. I.V. acknowledges support by the U.S. Department of Energy, Office of Science under Award Number 0000231415. |
Approved |
Most recent IF: 19; 2020 IF: 12.124 |
Call Number |
UA @ admin @ c:irua:165705 |
Serial |
6325 |
Permanent link to this record |
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Author |
Tang, Z.; Liu, P.; Cao, H.; Bals, S.; Heeres, H.J.; Pescarmona, P.P. |
Title |
Pr/ZrO2 prepared by atomic trapping : an efficient catalyst for the conversion of glycerol to lactic acid with concomitant transfer hydrogenation of cyclohexene |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
Volume |
9 |
Issue |
9 |
Pages |
9953-9963 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A series of heterogeneous catalysts consisting of highly dispersed Pt nanoparticles supported on nanosized ZrO2 (20 to 60 nm) was synthesized and investigated for the one-pot transfer hydrogenation between glycerol and cyclohexene to produce lactic acid and cyclohexane, without any additional H-2. Different preparation methods were screened, by varying the calcination and reduction procedures with the purpose of optimizing the dispersion of Pt species (i.e., as single-atom sites or extra-fine Pt nanoparticles) on the ZrO2 support. The Pt/ZrO2 catalysts were characterized by means of transmission electron microscopy techniques (HAADF-STEM, TEM), elemental analysis (ICP-OES, EDX mapping), N-2-physisorption, H-2 temperature-programmed-reduction (H-2-TPR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Based on this combination of techniques it was possible to correlate the temperature of the calcination and reduction treatments with the nature of the Pt species. The best catalyst consisted of subnanometer Pt clusters (<1 nm) and atomically dispersed Pt (as Pt2+ and Pt4+) on the ZrO2 support, which were converted into extra-fine Pt nanoparticles (average size = 1.4 nm) upon reduction. These nanoparticles acted as catalytic species for the transfer hydrogenation of glycerol with cyclohexene, which gave an unsurpassed 95% yield of lactic acid salt at 96% glycerol conversion (aqueous glycerol solution, NaOH as promoter, 160 degrees C, 4.5 h, at 20 bar N-2). This is the highest yield and selectivity of lactic acid (salt) reported in the literature so far. Reusability experiments showed a partial and gradual loss of activity of the Pt/ZrO2 catalyst, which was attributed to the experimentally observed aggregation of Pt nanoparticles. |
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 |
000494549700025 |
Publication Date |
2019-09-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
|
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.614 |
Times cited |
46 |
Open Access |
OpenAccess |
Notes |
Zhenchen Tang acknowledges the financial support from the China Scholarship Council for his Ph.D. grant. All the authors are grateful for the technical support from Erwin Wilbers, Anne Appeldoorn, and Marcel de Vries, the TEM support from Dr. Marc Stuart, and the ICP-OES support from Johannes van der Velde. Pei Liu and Sara Bals acknowledge financial support from the European Commission under the Horizon 2020 Programme by means of grant agreement No. 731019 EUSMI. |
Approved |
Most recent IF: 10.614 |
Call Number |
UA @ admin @ c:irua:164643 |
Serial |
6326 |
Permanent link to this record |
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Author |
Pittarello, L.; Mckibbin, S.; Yamaguchi, A.; Ji, G.; Schryvers, D.; Debaille, V.; Claeys, P. |
Title |
Two generations of exsolution lamellae in pyroxene from Asuka 09545 : Clues to the thermal evolution of silicates in mesosiderite |
Type |
A1 Journal article |
Year |
2019 |
Publication |
The American mineralogist |
Abbreviated Journal |
Am Mineral |
Volume |
104 |
Issue |
11 |
Pages |
1663-1672 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Mesosiderite meteorites consist of a mixture of crustal basaltic or gabbroic material and metal. Their formation process is still debated due to their unexpected combination of crust and core materials, possibly derived from the same planetesimal parent body, and lacking an intervening mantle component. Mesosiderites have experienced an extremely slow cooling rate from ca. 550 degrees C, as recorded in the metal (0.25-0.5 degrees C/Ma). Here we present a detailed investigation of exsolution features in pyroxene from the Antarctic mesosiderite Asuka (A) 09545. Geothermobarometry calculations, lattice parameters, lamellae orientation, and the presence of clinoenstatite as the host were used in an attempt to constrain the evolution of pyroxene from 1150 to 570 degrees C and the formation of two generations of exsolution lamellae. After pigeonite crystallization at ca. 1150 degrees C, the first exsolution process generated the thick augite lamellae along (100) in the temperature interval 1000-900 degrees C. By further cooling, a second order of exsolution lamellae formed within augite along (001), consisting of monoclinic low-Ca pyroxene, equilibrated in the temperature range 900-800 degrees C. The last process, occurring in the 600-500 degrees C temperature range, was likely the inversion of high to low pigeonite in the host crystal, lacking evidence for nucleation of orthopyroxene. The formation of two generations of exsolution lamellae, as well as of likely metastable pigeonite, suggest non-equilibrium conditions. Cooling was sufficiently slow to allow the formation of the lamellae, their preservation, and the transition from high to low pigeonite. In addition, the preservation of such fine-grained lamellae limits long-lasting, impact reheating to a peak temperature lower than 570 degrees C. These features, including the presence of monoclinic low-Ca pyroxene as the host, are reported in only a few mesosiderites. This suggests a possibly different origin and thermal history from most mesosiderites and that the crystallography (i.e., space group) of low-Ca pyroxene could be used as parameter to distinguish mesosiderite populations based on their cooling history. |
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 |
000494707400014 |
Publication Date |
2019-08-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
|
ISSN |
0003-004x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.021 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.021 |
Call Number |
UA @ admin @ c:irua:164645 |
Serial |
6331 |
Permanent link to this record |
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Author |
González-Rubio, G.; Milagres de Oliveira, T.; Albrecht, W.; Díaz-Núñez, P.; Castro-Palacio, J.C.; Prada, A.; González, R.I.; Scarabelli, L.; Bañares, L.; Rivera, A.; Liz-Marzán, L.M.; Peña-Rodríguez, O.; Bals, S.; Guerrero-Martínez, A. |
Title |
Formation of Hollow Gold Nanocrystals by Nanosecond Laser Irradiation |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Physical Chemistry Letters |
Abbreviated Journal |
J Phys Chem Lett |
Volume |
11 |
Issue |
11 |
Pages |
670-677 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The irradiation of spherical gold nanoparticles (AuNPs) with nanosecond laser pulses induces shape transformations yielding nanocrystals with an inner cavity. The concentration of the stabilizing surfactant, the use of moderate pulse fluences, and the size of the irradiated AuNPs determine the efficiency of the process and the nature of the void. Hollow nanocrystals are obtained when molecules from the surrounding medium (e.g., water and organic matter derived from the surfactant) are trapped during laser pulse irradiation. These experimental observations suggest the existence of a subtle balance between the heating and cooling processes experienced by the nanocrystals, which induce their expansion and subsequent recrystallization keeping exogenous matter inside. The described approach provides valuable insight into the mechanism of interaction of pulsed nanosecond laser with AuNPs, along with interesting prospects for the development of hollow plasmonic nanoparticles with potential applications related to gas and liquid storage at the nanoscale. |
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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 |
000512223400012 |
Publication Date |
2020-02-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
1948-7185 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.7 |
Times cited |
15 |
Open Access |
OpenAccess |
Notes |
This work has been funded by the Spanish Ministry of Science, Innovation and Universities (MICIU) (Grants RTI2018-095844-B-I00, PGC2018-096444-B-I00, ENE2015-70300-C3-3, and MAT2017-86659-R), the EUROfusion Consortium (Grant ENR-IFE19.CCFE-01) and the Madrid Regional Government (Grants P2018/NMT-4389 and P2018/EMT-4437). This project has received funding from the European Commission (grant 731019, EUSMI & grant 823717, ESTEEM3). The publication is based also upon work from COST Action TUMIEE (CA17126). The facilities provided by the Center for Ultrafast Lasers at Complutense University of Madrid are gratefully acknowledged. The authors also acknowledge the computer resources and technical assistance provided by the Centro de Supercomputacion y Visualizacion de Madrid (CeSViMa). L.M.L.-M. acknowledges the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant MDM-2017-0720). This project has also received funding from the European Research Council (ERC Consolidator Grant 815128, REALNANO). W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (Grant 797153, SOPMEN). A.P. and R.I.G. acknowledge the support of FONDECYT under Grants 3190123 and 11180557 and Financiamiento Basal para Centros Cientificos y Tecnologicos de Excelencia FB-0807. This research was partially supported by the supercomputing infrastructure of the NLHPC (ECM-02).; sygma; esteem3JRA; esteem3reported |
Approved |
Most recent IF: 5.7; 2020 IF: 9.353 |
Call Number |
EMAT @ emat @c:irua:166504 |
Serial |
6334 |
Permanent link to this record |
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Author |
Smith, J.D.; Bladt, E.; Burkhart, J.A.C.; Winckelmans, N.; Koczkur, K.M.; Ashberry, H.M.; Bals, S.; Skrabalak, S.E. |
Title |
Defect‐Directed Growth of Symmetrically Branched Metal Nanocrystals |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Angewandte Chemie (International ed. Print) |
Abbreviated Journal |
Angew. Chem. |
Volume |
132 |
Issue |
132 |
Pages |
953-960 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Branched plasmonic nanocrystals (NCs) have attracted much attention due to electric field enhancements at their tips. Seeded growth provides routes to NCs with defined branching patterns and, in turn, near‐field distributions with defined symmetries. Here, a systematic analysis was undertaken in which seeds containing different distributions of planar defects were used to grow branched NCs in order to understand how their distributions direct the branching. Characterization of the products by multimode electron tomography and analysis of the NC morphologies at different overgrowth stages indicate that the branching patterns are directed by the seed defects, with the emergence of branches from the seed faces consistent with minimizing volumetric strain energy at the expense of surface energy. These results contrast with growth of branched NCs from single‐crystalline seeds and provide a new platform for the synthesis of symmetrically branched plasmonic NCs. |
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 |
000505279500063 |
Publication Date |
2020-01-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
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Edition |
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ISSN |
0044-8249 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
The authors thank Samantha Harvey for her initial observations of branched structures, Alexander Chen for his help with SAED, the staff of the Nanoscale Characterization Facility (Dr. Yi Yi),Electron Microscopy Center (Dr. David Morgan and Dr. Barry Stein), and Molecular Strucre Center at Indiana University. J.S. recognizes a fellowship provided by the Indiana Space Grant Consortium. E. B. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). This project has received funding from the National Science Foundation (award number: 1602476), Research Corporation for Scietific Advancement (2017 Frontiers in Research Excellence and Discovery Award), and the European Union’s Horizon 2020 research and innovation program under grant agreement No 731019 (EUSMI) and No 815128 (REALNANO).; sygma |
Approved |
Most recent IF: NA |
Call Number |
EMAT @ emat @c:irua:166581 |
Serial |
6336 |
Permanent link to this record |
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Author |
Saveleva, V.A.; Wang, L.; Kasian, O.; Batuk, M.; Hadermann, J.; Gallet, J.-j.; Bournel, F.; Alonso-Vante, N.; Ozouf, G.; Beauger, C.; Mayrhofer, K.J.J.; Cherevko, S.; Gago, A.S.; Friedrich, K.A.; Zafeiratos, S.; Savinova, E.R. |
Title |
Insight into the Mechanisms of High Activity and Stability of Iridium Supported on Antimony-Doped Tin Oxide Aerogel for Anodes of Proton Exchange Membrane Water Electrolyzers |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
Volume |
10 |
Issue |
4 |
Pages |
2508-2516 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The use of high amounts of iridium in industrial proton exchange membrane water electrolysers (PEMWE) could hinder their widespread use for the decarbonisation of society with hydrogen. Non-thermally oxidised Ir nanoparticles supported on antimony-doped tin oxide (SnO2:Sb, ATO) aerogel allow decreasing the use of the precious metal by more than 70 %, while enhancing the electro-catalytic activity and stability. To date the origin of these benefits remains unknown. Here we present clear evidence on the mechanisms that lead to the enhancement of the electrochemical properties of the catalyst. Operando near ambient pressure X-ray photoelectron spectroscopy on membrane electrode assemblies reveals a low degree of Ir oxidation, attributed to the oxygen spill-over from Ir to SnO2:Sb. Furthermore, the formation of highly unstable Ir(III) species is mitigated, while the decrease of Ir dissolution in Ir/SnO2:Sb is confirmed by inductively coupled plasma mass spectrometry (ICP-MS). The mechanisms that lead to the high activity and stability of Ir catalyst supported on SnO2:Sb aerogel for PEMWE are thus unveiled. |
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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 |
000516887400011 |
Publication Date |
2020-02-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
|
Edition |
|
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.9 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
The research leading to these results has received funding from the European Union’s Seventh Framework Program (FP7/2007-2013) for Fuel Cell and Hydrogen Joint Technology (FCH JU) Initiative under Grant No. 621237 (INSIDE). In addition, A.S.G. and C.B. thank the European Union’s Horizon 2020 research and innovation programme for funding the project PRETZEL under grant agreement No 779478 and it is supported by FCH JU. Solvay is acknowledged for providing Aquivion membrane and ionomer. |
Approved |
Most recent IF: 12.9; 2020 IF: 10.614 |
Call Number |
EMAT @ emat @c:irua:167147 |
Serial |
6341 |
Permanent link to this record |
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Author |
Ciocarlan, R.-G.; Seftel, E.M.; Gavrila, R.; Suchea, M.; Batuk, M.; Mertens, M.; Hadermann, J.; Cool, P. |
Title |
Spinel nanoparticles on stick-like Freudenbergite nanocomposites as effective smart-removal photocatalysts for the degradation of organic pollutants under visible light |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
Volume |
820 |
Issue |
|
Pages |
153403 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
A series of mixed nanocomposite materials was synthetized, containing a Ferrite phase type Zn1-xNixFe2O4 and a Freudenbergite phase type Na2Fe2Ti6O16, where x = 0; 0.2; 0.4; 0.6; 0.8; 1. The choice for this combination is based on the good adsorption properties of Freudenbergite for dye molecules, and the small bandgap energy of Ferrite spinel, allowing activation of the catalysts under visible light irradiation. A two steps synthesis protocol was used to obtain the smart-removal nanocomposites. Firstly, the spinel structure was obtained via the co-precipitation route followed by the addition of the Ti-source and formation of the Freudenbergite system. The role of cations on the formation mechanism and an interesting interchange of cations between spinel and Freudenbergite structures was clarified by a TEM study. Part of the Ti4+ penetrated the spinel structure and, at the same time, part of the Fe3+ formed the Freudenbergite system. The photocatalytic activity was studied under visible light, reaching for the best catalysts a 67% and 40% mineralization degree for methylene blue and rhodamine 6G respectively, after 6 h of irradiation. In the same conditions, the well-known commercial P25 (Degussa) managed to mineralize only 12% and 3% of methylene blue and rhodamine 6G, respectively. Due to the remarkable magnetic properties of Ferrites, a convenient recovery and reuse of the catalysts is possible after the photocatalytic tests. Based on the excellent catalytic performance of the nanocomposites under visible light and their ease of separation out of the solution after the catalytic reaction, the newly developed composite catalysts are considered very effective for wastewater treatment. |
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 |
000507854700130 |
Publication Date |
2019-12-15 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume ![sorted by Series Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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Series Issue |
|
Edition |
|
ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.2 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
The authors acknowledge the FWO-Flanders (project nr. G038215N) for financial support. |
Approved |
Most recent IF: 6.2; 2020 IF: 3.133 |
Call Number |
EMAT @ emat @c:irua:166447 |
Serial |
6342 |
Permanent link to this record |
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Author |
Rumyantseva, M.N.; Vladimirova, S.A.; Platonov, V.B.; Chizhov, A.S.; Batuk, M.; Hadermann, J.; Khmelevsky, N.O.; Gaskov, A.M. |
Title |
Sub-ppm H2S sensing by tubular ZnO-Co3O4 nanofibers |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Sensors And Actuators B-Chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
Volume |
307 |
Issue |
|
Pages |
127624 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Tubular ZnO – Co3O4 nanofibers were co-electrospun from polymer solution containing zinc and cobalt acetates. Phase composition, cobalt electronic state and element distribution in the fibers were investigated by XRD, SEM, HRTEM, HAADF-STEM with EDX mapping, and XPS. Bare ZnO has high selective sensitivity to NO and NO2, while ZnO-Co3O4 composites demonstrate selective sensitivity to H2S in dry and humid air. This effect is discussed in terms of transformation of cobalt oxides into cobalt sulfides and change in the acidity of ZnO oxide surface upon cobalt doping. Reduction in response and recovery time is attributed to the formation of a tubular structure facilitating gas transport through the sensitive layer. |
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Wos |
000508110400059 |
Publication Date |
2019-12-24 |
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0925-4005 |
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UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.401 |
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Not_Open_Access |
Notes |
This work was supported by RFBR grants No. 18-03-00091 and No. 18-03-00580. |
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Most recent IF: NA |
Call Number |
EMAT @ emat @c:irua:166449 |
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6343 |
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