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Author | Liao, Z.; Gauquelin, N.; Green, R.J.; Müller-Caspary, K.; Lobato, I.; Li, L.; Van Aert, S.; Verbeeck, J.; Huijben, M.; Grisolia, M.N.; Rouco, V.; El Hage, R.; Villegas, J.E.; Mercy, A.; Bibes, M.; Ghosez, P.; Sawatzky, G.A.; Rijnders, G.; Koster, G. | ||||
Title | Metal–insulator-transition engineering by modulation tilt-control in perovskite nickelates for room temperature optical switching | Type | A1 Journal article | ||
Year | 2018 | Publication | America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 115 | Issue | 38 | Pages | 9515-9520 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | In transition metal perovskites ABO3 the physical properties are largely driven by the rotations of the BO6 octahedra, which can be tuned in thin films through strain and dimensionality control. However, both approaches have fundamental and practical limitations due to discrete and indirect variations in bond angles, bond lengths and film symmetry by using commercially available substrates. Here, we introduce modulation tilt control as a new approach to tune the ground state of perovskite oxide thin films by acting explicitly on the oxygen octahedra rotation modes, i.e. directly on the bond angles. By intercalating the prototype SmNiO3 target material with a tilt-control layer, we cause the system to change the natural amplitude of a given rotation mode without affecting the interactions. In contrast to strain and dimensionality engineering, our method enables a continuous fine-tuning of the materials properties. This is achieved through two independent adjustable parameters: the nature of the tilt-control material (through its symmetry, elastic constants and oxygen rotation angles) and the relative thicknesses of the target and tilt-control materials. As a result, a magnetic and electronic phase diagram can be obtained, normally only accessible by A-site element substitution, within the single SmNiO3 compound. With this unique approach, we successfully adjusted the metal-insulator transition (MIT) to room temperature to fulfill the desired conditions for optical switching applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000447224900057 | Publication Date | 2018-09-05 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.661 | Times cited | 50 | Open Access | OpenAccess |
Notes | We would like to acknowledge Prof. Z. Zhong for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010-246102 IFOX. J.V., S.V.A, N.G. and K.M.C. acknowledge funding from FWO projects G.0044.13N, G.0374.13N, G. 0368.15N, and G.0369.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G. and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483- ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. MB acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC CoG grant MINT #615759. A.M. and Ph.G. were supported by the ARC project AIMED and F.R.S-FNRS PDR project HiT4FiT and acknowledge access to Céci computing facilities funded by F.R.S-FNRS (Grant No 2.5020.1), Tier-1 supercomputer of the Fédération Wallonie-Bruxelles funded by the Walloon Region (Grant No 1117545) and HPC resources from the PRACE project Megapasta. | Approved | Most recent IF: 9.661 | ||
Call Number | EMAT @ emat @c:irua:154784UA @ admin @ c:irua:154784 | Serial | 5059 | ||
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Author | Krehl, J.; Guzzinati, G.; Schultz, J.; Potapov, P.; Pohl, D.; Martin, J.; Verbeeck, J.; Fery, A.; Büchner, B.; Lubk, A. | ||||
Title | Spectral field mapping in plasmonic nanostructures with nanometer resolution | Type | A1 Journal article | ||
Year | 2018 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 9 | Issue | 1 | Pages | 4207 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Plasmonic nanostructures and -devices are rapidly transforming light manipulation technology by allowing to modify and enhance optical fields on sub-wavelength scales. Advances in this field rely heavily on the development of new characterization methods for the fundamental nanoscale interactions. However, the direct and quantitative mapping of transient electric and magnetic fields characterizing the plasmonic coupling has been proven elusive to date. Here we demonstrate how to directly measure the inelastic momentum transfer of surface plasmon modes via the energy-loss filtered deflection of a focused electron beam in a transmission electron microscope. By scanning the beam over the sample we obtain a spatially and spectrally resolved deflection map and we further show how this deflection is related quantitatively to the spectral component of the induced electric and magnetic fields pertaining to the mode. In some regards this technique is an extension to the established differential phase contrast into the dynamic regime. | ||||
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Language | Wos | 000447074200005 | Publication Date | 2018-10-11 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 15 | Open Access | OpenAccess |
Notes | G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoke-Vlaanderen (FWO). A.L. and J.K. have received funding from the European Research Council (ERC) under the Horizon 2020 research and innovation program of the European Union (grant agreement no. 715620). | Approved | Most recent IF: 12.124 | ||
Call Number | EMAT @ emat @c:irua:154355 | Serial | 5058 | ||
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Author | Godet, M.; Vergès-Belmin, V.; Gauquelin, N.; Saheb, M.; Monnier, J.; Leroy, E.; Bourgon, J.; Verbeeck, J.; Andraud, C. | ||||
Title | Nanoscale investigation by TEM and STEM-EELS of the laser induced yellowing | Type | A1 Journal article | ||
Year | 2018 | Publication | Micron | Abbreviated Journal | Micron |
Volume | 115 | Issue | Pages | 25-31 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nd-YAG QS laser cleaning of soiled stone at 1064 nm can sometimes result in a more yellow appearance compared to other cleaning techniques. Especially in France, this yellowing effect is still considered as a major aesthetic issue by the architects and conservators. One explanation states that the yellowing is linked to the formation of iron-rich nanophase(s) through the laser beam interaction with black crusts that would re-deposit on the cleaned substrate after irradiation. To characterize these nanophases, a model crust containing hematite was elaborated and laser irradiated using a Nd-YAG QS laser. The color of the sample shifted instantaneously from red to a bright yellow and numerous particles were ablated in a visible smoke. Transmission electron microscopy (TEM) was used to examine the morphology and the crystallinity of the neo-formed compounds, both on the surface of the samples and in the ablated materials. In addition, an investigation of the chemical and structural properties of the nanophases was conducted by X-ray dispersive energy (EDX) and electron energy loss (EELS) spectroscopies. It was found that both the surface of the sample and the ablated materials are covered by crystallized nano-spheres and nano-residues, all containing iron and oxygen, sometimes along with calcium and sulfur. In particular an interfacial area containing the four elements was evidenced between some nanostructures and the substrate. Magnetite Fe3O4 was also identified at the nanoscale. This study demonstrates that the laser yellowing of a model crust is linked to the presence of iron-rich nanophases including CaxFeySzOδ nanostructures and magnetite Fe3O4 at the surface after irradiation. | ||||
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Language | Wos | 000449125600004 | Publication Date | 2018-08-18 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0968-4328 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.98 | Times cited | 9 | Open Access | Not_Open_Access: Available from 19.08.2020 |
Notes | The authors wish to thank Valérie Lalanne for the sample preparation for TEM and Stijn Van den Broeck for the FIB cut elaboration. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative–I3). | Approved | Most recent IF: 1.98 | ||
Call Number | EMAT @ emat @c:irua:154356UA @ admin @ c:irua:154356 | Serial | 5056 | ||
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Author | Fatermans, J.; Van Aert, S.; den Dekker, A.J. | ||||
Title | The maximum a posteriori probability rule for atom column detection from HAADF STEM images | Type | A1 Journal article | ||
Year | 2019 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 201 | Issue | Pages | 81-91 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | Recently, the maximum a posteriori (MAP) probability rule has been proposed as an objective and quantitative method to detect atom columns and even single atoms from high-resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images. The method combines statistical parameter estimation and model-order selection using a Bayesian framework and has been shown to be especially useful for the analysis of the structure of beam-sensitive nanomaterials. In order to avoid beam damage, images of such materials are usually acquired using a limited incoming electron dose resulting in a low contrast-to-noise ratio (CNR) which makes visual inspection unreliable. This creates a need for an objective and quantitative approach. The present paper describes the methodology of the MAP probability rule, gives its step-by-step derivation and discusses its algorithmic implementation for atom column detection. In addition, simulation results are presented showing that the performance of the MAP probability rule to detect the correct number of atomic columns from HAADF STEM images is superior to that of other model-order selection criteria, including the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC). Moreover, the MAP probability rule is used as a tool to evaluate the relation between STEM image quality measures and atom detectability resulting in the introduction of the so-called integrated CNR (ICNR) as a new image quality measure that better correlates with atom detectability than conventional measures such as signal-to-noise ratio (SNR) and CNR. | ||||
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Language | Wos | 000466343800009 | Publication Date | 2019-02-04 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 1 | Open Access | OpenAccess |
Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (No. W.O.010.16N, No. G.0368.15N, No. G.0502.18N). This project has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (Grant Agreement No. 770887). | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157176 | Serial | 5153 | ||
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Author | Bercx, M.; Partoens, B.; Lamoen, D. | ||||
Title | Quantitative modeling of secondary electron emission from slow-ion bombardment on semiconductors | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 99 | Issue | 8 | Pages | 085413 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | When slow ions incident on a surface are neutralized, the excess potential energy is passed on to an electron inside the surface, leading to emission of secondary electrons. The microscopic description of this process, as well as the calculation of the secondary electron yield, is a challenging problem due to its complexity as well as its sensitivity to surface properties. One of the first quantitative descriptions was articulated in the 1950s by Hagstrum, who based his calculation on a parametrization of the density of states of the material. In this paper, we present a model for calculating the secondary electron yield, derived from Hagstrum’s initial approach. We use first-principles density functional theory calculations to acquire the necessary input and introduce the concept of electron cascades to Hagstrum’s model in order to improve the calculated spectra, as well as remove its reliance on fitting parameters. We apply our model to He+ and Ne+ ions incident on Ge(111) and Si(111) and obtain yield spectra that match closely to the experimental results of Hagstrum. |
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Language | Wos | 000458367800010 | Publication Date | 2019-02-11 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 5 | Open Access | OpenAccess |
Notes | We would like to thank Prof. D. Depla for the useful discussions on the secondary electron yield. Furthermore, we acknowledge financial support of FWO-Vlaanderen through project G.0216.14N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWOVlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 3.836 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157174 | Serial | 5154 | ||
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Author | Van Aert, S.; De Backer, A.; Jones, L.; Martinez, G.T.; Béché, A.; Nellist, P.D. | ||||
Title | Control of Knock-On Damage for 3D Atomic Scale Quantification of Nanostructures: Making Every Electron Count in Scanning Transmission Electron Microscopy | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 122 | Issue | 6 | Pages | 066101 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Understanding nanostructures down to the atomic level is the key to optimizing the design of advancedmaterials with revolutionary novel properties. This requires characterization methods capable of quantifying the three-dimensional (3D) atomic structure with the highest possible precision. A successful approach to reach this goal is to count the number of atoms in each atomic column from 2D annular dark field scanning transmission electron microscopy images. To count atoms with single atom sensitivity, a minimum electron dose has been shown to be necessary, while on the other hand beam damage, induced by the high energy electrons, puts a limit on the tolerable dose. An important challenge is therefore to develop experimental strategies to optimize the electron dose by balancing atom-counting fidelity vs the risk of knock-on damage. To achieve this goal, a statistical framework combined with physics-based modeling of the dose-dependent processes is here proposed and experimentally verified. This model enables an investigator to theoretically predict, in advance of an experimental measurement, the optimal electron dose resulting in an unambiguous quantification of nanostructures in their native state with the highest attainable precision. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000458824200008 | Publication Date | 2019-02-13 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 3 | Open Access | OpenAccess |
Notes | This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (WO.010.16N, G.0934.17N, G.0502.18N, G.0267.18N), and a grant to A. D. B. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement No. 312483— ESTEEM2 (Integrated Infrastructure Initiative-I3) and the UK EPSRC (Grant No. EP/M010708/1). | Approved | Most recent IF: 8.462 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157175 | Serial | 5156 | ||
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Author | Müller-Caspary, K.; Grieb, T.; Müßener, J.; Gauquelin, N.; Hille, P.; Schörmann, J.; Verbeeck, J.; Van Aert, S.; Eickhoff, M.; Rosenauer, A. | ||||
Title | Electrical Polarization in AlN/GaN Nanodisks Measured by Momentum-Resolved 4D Scanning Transmission Electron Microscopy | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 122 | Issue | 10 | Pages | 106102 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report the mapping of polarization-induced internal electric fields in AlN/GaN nanowire heterostructures at unit cell resolution as a key for the correlation of optical and structural phenomena in semiconductor optoelectronics. Momentum-resolved aberration-corrected scanning transmission electron microscopy is employed as a new imaging mode that simultaneously provides four-dimensional data in real and reciprocal space. We demonstrate how internal mesoscale and atomic electric fields can be separated in an experiment, which is verified by comprehensive dynamical simulations of multiple electron scattering. A mean difference of 5.3 +- 1.5 MV/cm is found for the polarization-induced electric fields in AlN and GaN, being in accordance with dedicated simulations and photoluminescence measurements in previous publications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000461067700007 | Publication Date | 2019-03-11 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 26 | Open Access | OpenAccess |
Notes | The authors gratefully acknowledge the help of Natalie Claes for analyzing the EDX data. K. M.-C. acknowledges funding from the Initiative and Network Fund of the Helmholtz Association within the Helmholtz Young Investigator Group moreSTEM under Contract No. VHNG- 1317 at Forschungszentrum Jülich in Germany. The direct electron detector (Medipix3, Quantum Detectors) was funded by the Hercules fund from the Flemish Government. N. G. and J. V. acknowledge funding from the Geconcentreerde Onderzoekacties project Solarpaint of the University of Antwerp. T. G. and A. R. acknowledge support from the Deutsche Forschungsgemeinschaft (Germany) under Contract No. RO2057/8-3. This work also received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme (Contract No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0368.15N).; Helmholtz Association, VH-NG-1317 ; Forschungszentrum Jülich; Flemish Government; Universiteit Antwerpen; Deutsche Forschungsgemeinschaft, RO2057/8-3 ; H2020 European Research Council, 770887 ; Fonds Wetenschappelijk Onderzoek, G.0368.15N ; | Approved | Most recent IF: 8.462 | ||
Call Number | UA @ lucian @UA @ admin @ c:irua:158120 | Serial | 5157 | ||
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Author | Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q. | ||||
Title | Study of the Q′ (Q)-phase precipitation in Al–Mg–Si–Cu alloys by quantification of atomic-resolution transmission electron microscopy images and atom probe tomography | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of materials science | Abbreviated Journal | J Mater Sci |
Volume | 54 | Issue | 10 | Pages | 7943-7952 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The precipitation mechanism of the Q phase in Al-Mg-Si-Cu alloys has long been the subject of ambiguity and debate since its metastable phase (Q 0) has the same crystal structure and similar lattice parameters as its equilibrium counterparts. In the present work, the evolution of the Q 0 (Q) phase during aging is studied by combination of quantitative atomic-resolution scanning transmission electron microscopy and atom probe tomography. It was found that the transformation from the Q 0 to the Q phase involves changes of the occupancy of Al atoms in atomic columns of the Q 0 (Q) phase. The Al atoms incorporated in the Cu, Si and Mg columns are gradually released into the Al matrix, while mixing between Cu and Si atoms occurs in the Si columns. This transformation process is mainly attributed to the low lattice misfit of the equilibrium Q phase. Besides, the formation of various compositions of the Q phase is due to the different occupancy in the atomic columns of the Q phase. The occupancy changes in the columns of the Q phase are kinetically controlled and are strongly influenced by the alloy composition and aging temperature. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000460069500043 | Publication Date | 2019-02-14 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0022-2461 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.599 | Times cited | 1 | Open Access | Not_Open_Access |
Notes | Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing, cstc2017zdcy-zdzxX0006 ; Fundamental Research Funds for the Central Universities of China, 2018CDGFCL0002 106112017CDJQJ308822 ; Belgian National Fund for Scientific Research; the National Natural Science Foundation of China, 51871035 ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant No. cstc2017zdcyzdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDGFCL0002), the National Natural Science Foundation of China (Grant No. 51871035) and the Foundation for Innovative Research Groups J Mater Sci National Natural Science Foundation of China (Grant No. 51421001). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). | Approved | Most recent IF: 2.599 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:158112 | Serial | 5158 | ||
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Author | Miotti Bettanini, A.; Ding, L.; Mithieux, J.-D.; Parrens, C.; Idrissi, H.; Schryvers, D.; Delannay, L.; Pardoen, T.; Jacques, P.J. | ||||
Title | Influence of M23C6 dissolution on the kinetics of ferrite to austenite transformation in Fe-11Cr-0.06C stainless steel | Type | A1 Journal article | ||
Year | 2019 | Publication | Materials & design | Abbreviated Journal | Mater Design |
Volume | 162 | Issue | Pages | 362-374 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The design of high-strength martensitic stainless steels requires an accurate control over the stability of undesired phases, like carbides and ferrite, which can hamper strength and ductility. Here, the ferrite to austenite transformation in Fe-11Cr-0.06C has been studied with a combined experimental-modelling approach. Experimental observations of the austenization process indicate that austenite growth proceeds in multiple steps, each one characterized by a different transformation rate. DICTRA based modelling reveals that the dissolution of the M23C6 Cr-rich carbides leads to Cr partitioning between austenite and parent phases, which controls the rate of transformation through (i) a soft-impingement effect and (ii) consequent stabilization of the ferrite, which remains untransformed inside chromium-enriched-zones even after prolonged austenization stage. Slow heating rate and smaller initial particle sizes allow the design of ferrite-free microstructure. | ||||
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Language | Wos | 000454128400036 | Publication Date | 2018-12-06 | |
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ISSN | 0264-1275 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.364 | Times cited | 3 | Open Access | OpenAccess |
Notes | The authors thank Professor Anne-Francoise Gourgues-Lorenzon and Helene Godin, Ecole Nationale Superiore des Mines de Paris (MINES ParisTech) for their fruitful discussions. AMB thanks Stijn Van den broek (Universiteit Antwerpen) for the skillful preparation of TEM samples with FIB. The financial support of CBMM (Companhia Brasileira de Metalurgia e Mineracao) is gratefully acknowledged. L. Delannay is mandated by the FNRS-Belgium. Computational resources have been provided by the supercomputing facilities of the UCLouvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en Federation Wallonie Bruxelles (CÉCI) funded by the Fond de la Recherche Scientifique de Belgique (F.R.S.-FNRS) under convention 2.5020.11.; Cbmm; F.r.s.-fnrs, 2.5020.11 ; | Approved | Most recent IF: 4.364 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:156721 | Serial | 5161 | ||
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Author | Cautaerts, N.; Delville, R.; Schryvers, D. | ||||
Title | ALPHABETA: a dedicated open-source tool for calculating TEM stage tilt angles | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of microscopy | Abbreviated Journal | J Microsc-Oxford |
Volume | 273 | Issue | 3 | Pages | 189-198 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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Language | Wos | 000458426100004 | Publication Date | 2018-12-24 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0022-2720 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.692 | Times cited | 2 | Open Access | Not_Open_Access |
Notes | ENGIE Ph.D. sponsorship, 2015-AC-007 – BSUEZ6900 ; | Approved | Most recent IF: 1.692 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157474 | Serial | 5163 | ||
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Author | Charalampopoulou, E.; Delville, R.; Verwerft, M.; Lambrinou, K.; Schryvers, D. | ||||
Title | Transmission electron microscopy study of complex oxide scales on DIN 1.4970 steel exposed to liquid Pb-Bi eutectic | Type | A1 Journal article | ||
Year | 2019 | Publication | Corrosion science | Abbreviated Journal | Corrosion Science |
Volume | 147 | Issue | Pages | 22-31 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The deployment of Gen-IV lead-cooled fast reactors requires a good compatibility between the selected structural/cladding steels and the inherently corrosive heavy liquid metal coolant. An effective liquid metal corrosion mitigation strategy involves the in-situ steel passivation in contact with the oxygen-containing Pb-alloy coolant. Transmission electron microscopy was used in this work to study the multi-layered oxide scales forming on an austenitic stainless steel fuel cladding exposed to oxygen-containing (CO ≈ 10−6 mass%) static liquid leadbismuth eutectic (LBE) for 1000 h between 400 and 500 °C. The oxide scale constituents were analyzed, including the intertwined phases comprising the innermost biphasic layer. | ||||
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Language | Wos | 000456902100003 | Publication Date | 2018-10-31 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0010938X | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 5 | Open Access | OpenAccess | |
Notes | The authors would like to thank J. Joris for the technical support during corrosion testing and J. Lim for the manufacturing and calibration of the oxygen sensors and oxygen pumps used in this work. E. Charalampopoulou personally thanks H. Heidari, S. Pourbabak, A. Orekhov (EMAT) and N. Cautaerts (EMAT, SCK•CEN), for their valuable help with the training of the FEI Tecnai Osiris S/TEM and Jeol 3000 S/ TEM, respectively, as well as S. Van den Broeck (EMAT), J. Pakarinen (SCK•CEN) and W. Van Renterghem (SCK•CEN) for FIB sample preparation. Moreover, the authors gratefully acknowledge the funding provided in the framework of the ongoing development of the MYRRHA irradiation facility. The research leading to these results falls within the framework of the European Energy Research Alliance Joint Programme on Nuclear Materials (EERA JPNM). | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157541 | Serial | 5164 | ||
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Author | Scarabelli, L.; Schumacher, M.; Jimenez de Aberasturi, D.; Merkl, J.‐P.; Henriksen‐Lacey, M.; Milagres de Oliveira, T.; Janschel, M.; Schmidtke, C.; Bals, S.; Weller, H.; Liz‐Marzán, L.M. | ||||
Title | Encapsulation of Noble Metal Nanoparticles through Seeded Emulsion Polymerization as Highly Stable Plasmonic Systems | Type | A1 Journal article | ||
Year | 2019 | Publication | Advanced functional materials | Abbreviated Journal | Adv Funct Mater |
Volume | 29 | Issue | 29 | Pages | 1809071 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The implementation of plasmonic nanoparticles in vivo remains hindered by important limitations such as biocompatibility, solubility in biological fluids, and physiological stability. A general and versatile protocol is presented, based on seeded emulsion polymerization, for the controlled encapsulation of gold and silver nanoparticles. This procedure enables the encapsulation of single nanoparticles as well as nanoparticle clusters inside a protecting polymer shell. Specifically, the efficient coating of nanoparticles of both metals is demonstrated, with final dimensions ranging between 50 and 200 nm, i.e., sizes of interest for bio-applications. Such hybrid nanocomposites display extraordinary stability in high ionic strength and oxidizing environments, along with high cellular uptake, and low cytotoxicity. Overall, the prepared nanostructures are promising candidates for plasmonic applications under biologically relevant conditions. | ||||
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Language | Wos | 000467109100024 | Publication Date | 2019-02-11 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 1616-301X | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 19 | Open Access | OpenAccess |
Notes | L.S. and M.S. contributed equally to this work. This work was supported by the Spanish MINECO (Grant MAT2017-86659-R), by the German Research Foundation (DFG, Grant LA 2901/1-1) and by the European Research Council (Grant 335078 COLOURATOM to S.B). The authors acknowledge funding from the European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M). L.S. acknowledges funding from the American-Italian Cancer Foundation through a Post-Doctoral Research Fellowship. D.J.d.A. thanks MINECO for a Juan de la Cierva fellowship (IJCI-2015-24264). J.P.M. was financed by Verband der Chemischen Industrie e.V. (VCI). The authors thank Dr. Artur Feld, Dr. Andreas Kornowski and Stefan Werner (Institute of Physical Chemistry, University of Hamburg) for their support. | Approved | Most recent IF: 12.124 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:160710 | Serial | 5190 | ||
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Author | Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. | ||||
Title | Spectroscopic coincidence experiments in transmission electron microscopy | Type | A1 Journal article | ||
Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 114 | Issue | 14 | Pages | 143101 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We demonstrate the feasibility of coincidence measurements on a conventional transmission electron microscope, revealing the temporal correlation between electron energy loss spectroscopy (EELS) and energy dispersive X-ray (EDX) spectroscopy events. We make use of a delay line detector with ps-range time resolution attached to a modified EELS spectrometer. We demonstrate that coincidence between both events, related to the excitation and deexcitation of atoms in a crystal, provides added information not present in the individual EELS or EDX spectra. In particular, the method provides EELS with a significantly suppressed or even removed background, overcoming the many difficulties with conventional parametric background fitting as it uses no assumptions on the shape of the background, requires no user input and does not suffer from counting noise originating from the background signal. This is highly attractive, especially when low concentrations of elements need to be detected in a matrix of other elements. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000464450200022 | Publication Date | 2019-04-08 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 18 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G093417 ; Horizon 2020 Framework Programme, 823717 ESTEEM3 ; Helmholtz Association, VH-NG-1327 ; | Approved | Most recent IF: 3.411 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159155 | Serial | 5168 | ||
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Author | Saniz, R.; Sarmadian, N.; Partoens, B.; Batuk, M.; Hadermann, J.; Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Lamoen, D. | ||||
Title | First-principles study of CO and OH adsorption on in-doped ZnO surfaces | Type | A1 Journal article | ||
Year | 2019 | Publication | The journal of physics and chemistry of solids | Abbreviated Journal | J Phys Chem Solids |
Volume | 132 | Issue | Pages | 172-181 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We present a first-principles computational study of CO and OH adsorption on non-polar ZnO (10¯10) surfaces doped with indium. The calculations were performed using a model ZnO slab. The position of the In dopants was varied from deep bulk-like layers to the surface layers. It was established that the preferential location of the In atoms is at the surface by examining the dependence of the defect formation energy as well as the surface energy on In location. The adsorption sites on the surface of ZnO and the energy of adsorption of CO molecules and OH-species were determined in connection to In doping. It was found that OH has higher bonding energy to the surface than CO. The presence of In atoms at the surface of ZnO is favorable for CO adsorption, resulting in an elongation of the C-O bond and in charge transfer to the surface. The effect of CO and OH adsorption on the electronic and conduction properties of surfaces was assessed. We conclude that In-doped ZnO surfaces should present a higher electronic response upon adsorption of CO. |
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Language | Wos | 000472124700023 | Publication Date | 2019-04-25 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0022-3697 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.059 | Times cited | 7 | Open Access | Not_Open_Access: Available from 26.04.2021 |
Notes | FWO-Vlaanderen, G0D6515N ; ERA.Net RUS Plus, 096 ; VSC; HPC infrastructure of the University of Antwerp; FWO-Vlaanderen; Flemish Government-department EWI; | Approved | Most recent IF: 2.059 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159656 | Serial | 5170 | ||
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Author | Vanrompay, H.; Béché, A.; Verbeeck, J.; Bals, S. | ||||
Title | Experimental Evaluation of Undersampling Schemes for Electron Tomography of Nanoparticles | Type | A1 Journal article | ||
Year | 2019 | Publication | Particle and particle systems characterization | Abbreviated Journal | Part Part Syst Char |
Volume | 36 | Issue | 36 | Pages | 1900096 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | One of the emerging challenges in the field of 3D characterization of nanoparticles by electron tomography is to avoid degradation and deformation of the samples during the acquisition of a tilt series. In order to reduce the required electron dose, various undersampling approaches have been proposed. These methods include lowering the number of 2D projection images, reducing the probe current during the acquisition, and scanning a smaller number of pixels in the 2D images. A comparison is made between these approaches based on tilt series acquired for a gold nanoparticle. | ||||
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Language | Wos | 000477679400014 | Publication Date | 2019-05-29 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0934-0866 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.474 | Times cited | 12 | Open Access | Not_Open_Access |
Notes | H.V. acknowledges financial support by the Research Foundation Flanders (FWO Grant No. 1S32617N). A.B. and J.V. acknowledge FWO project 6093417N “Compressed sensing enabling low dose imaging in STEM.” The authors thank G. González-Rubio, A. Sánchez-Iglesias, and L.M. Liz-Marzán for provision of the samples. | Approved | Most recent IF: 4.474 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159986 | Serial | 5175 | ||
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Author | Montero-Sistiaga, M.L.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D.; Vanmeensel, K. | ||||
Title | Microstructure and mechanical properties of Hastelloy X produced by HP-SLM (high power selective laser melting) | Type | A1 Journal article | ||
Year | 2019 | Publication | Materials & design | Abbreviated Journal | Mater Design |
Volume | 165 | Issue | Pages | 107598 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In order to increase the production rate during selective laser melting (SLM), a high power laser with a large beam diameter is used to build fully dense Hastelloy X parts. Compared to SLM with a low power and small diameter beam, the productivity was increased from 6 mm3/s to 16 mm3/s, i.e. 2.6 times faster. Besides the productivity benefit, the influence of the use of a high power laser on the rapid solidification microstructure and concomitant material properties is highlighted. The current paper compares the microstructure and tensile properties of Hastelloy X built with low and high power lasers. The use of a high power laser results in wider and shallower melt pools inducing an enhanced morphological and crystallographic texture along the building direction (BD). In addition, the increased heat input results in coarser sub-grains or high density dislocation walls for samples processed with a high power laser. Additionally, the influence of hot isostatic pressing (HIP) as a post-processing technique was evaluated. After HIP, the tensile fracture strain increased as compared to the strain in the as-built state and helped in obtaining competitive mechanical properties as compared to conventionally processed Hastelloy X parts. | ||||
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Language | Wos | 000458259300020 | Publication Date | 2019-01-09 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0264-1275 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.364 | Times cited | 15 | Open Access | OpenAccess |
Notes | This research was supported by the ENGIE Research and Technology Division. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine. S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. | Approved | Most recent IF: 4.364 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157469 | Serial | 5176 | ||
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Author | Pourbabak, S.; Orekhov, A.; Samaee, V.; Verlinden, B.; Van Humbeeck, J.; Schryvers, D. | ||||
Title | In-Situ TEM Stress Induced Martensitic Transformation in Ni50.8Ti49.2 Microwires | Type | A1 Journal article | ||
Year | 2019 | Publication | Shape memory and superelasticity | Abbreviated Journal | Shap. Mem. Superelasticity |
Volume | 5 | Issue | 2 | Pages | 154-162 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In-situ transmission electron microscopy tensile straining is used to study the stress induced martensitic transformation in Ni50.8Ti49.2. Two microwire samples with different heat treatment are investigated from which one single crystal and three polycrystalline TEM specimens, the latter with micro- and nano-size grains, have been produced. The measured Young’s modulus for all TEM specimens is around 70 GPa, considerably higher than the averaged 55 GPa of the original microwire sample. The height of the superelastic stress plateau shows an inverse relationship with the specimen thickness for the polycrystalline specimens. Martensite starts nucleating within the elastic region of the stress–strain curve and on the edges of the specimens while also grain boundaries act as nucleation sites in the polycrystalline specimens. When a martensite plate reaches a grain boundary in the polycrystalline specimen, it initiates the transformation in the neighboring grain at the other side of the grain boundary. In later stages martensite plates coalesce at higher loads in the stress plateau. In highly strained specimens, residual martensite remains after release. | ||||
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Language | Wos | 000472940200002 | Publication Date | 2019-05-20 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2199-384X | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | Not_Open_Access | ||
Notes | Saeid Pourbabak likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. This work was also made possible through the AUHA13009 Grant “TopSPIN for TEM nanostatistics” of the Flemish HERCULES foundation. | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159989 | Serial | 5177 | ||
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Author | Pourbabak, S.; Montero-Sistiaga, M.L.; Schryvers, D.; Van Humbeeck, J.; Vanmeensel, K. | ||||
Title | Microscopic investigation of as built and hot isostatic pressed Hastelloy X processed by Selective Laser Melting | Type | A1 Journal article | ||
Year | 2019 | Publication | Materials characterization | Abbreviated Journal | Mater Charact |
Volume | 153 | Issue | Pages | 366-371 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Microstructural characteristics of Hastelloy X produced by Selective Laser Melting have been investigated by various microscopic techniques in the as built (AB) condition and after hot isostatic pressing (HIP). At sub-grain level the AB material consists of columnar high density dislocation cells while the HIP sample consists of columnar sub-grains with lower dislocation density that originate from the original dislocation cells, contradicting existing models. The sub-grains contain nanoscale precipitates enriched in Al, Ti, Cr and O, located at sub-grain boundaries in the AB condition and within the grains after HIP. At some grain boundaries, micrometer sized chromium carbides are detected after HIP. Micro hardness within the grains was found to decrease after HIP, which was attributed to the decrease in dislocation density due to recovery annealing. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000472696900040 | Publication Date | 2019-05-21 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 1044-5803 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.714 | Times cited | 2 | Open Access | Not_Open_Access |
Notes | S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine and financial support. This work was also made possible through the AUHA13009 grant “TopSPIN for TEM nanostatistics” of the Flemish HERCULES foundation. | Approved | Most recent IF: 2.714 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159974 | Serial | 5178 | ||
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Author | Bercx, M.; Slap, L.; Partoens, B.; Lamoen, D. | ||||
Title | First-Principles Investigation of the Stability of the Oxygen Framework of Li-Rich Battery Cathodes | Type | A1 Journal article | ||
Year | 2019 | Publication | MRS advances | Abbreviated Journal | MRS Adv. |
Volume | 4 | Issue | 14 | Pages | 813-820 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Lithium-rich layered oxides such as Li<sub>2</sub>MnO<sub>3</sub>have shown great potential as cathodes in Li-ion batteries, mainly because of their large capacities. However, these materials still suffer from structural degradation as the battery is cycled, reducing the average voltage and capacity of the cell. The voltage fade is believed to be related to the migration of transition metals into the lithium layer, linked to the formation of O-O dimers with a short bond length, which in turn is driven by the presence of oxygen holes due to the participation of oxygen in the redox process. We investigate the formation of O-O dimers for partially charged O1-Li<sub>2</sub>MnO<sub>3</sub>using a first-principles density functional theory approach by calculating the reaction energy and kinetic barriers for dimer formation. Next, we perform similar calculations for partially charged O1-Li<sub>2</sub>IrO<sub>3</sub>, a Li-rich material for which the voltage fade was not observed during cycling. When we compare the stability of the oxygen framework, we conclude that the formation of O-O dimers is both thermodynamically and kinetically viable for O1-Li<sub>0.5</sub>MnO<sub>3</sub>. For O1-Li<sub>0.5</sub>IrO<sub>3</sub>, we observe that the oxygen lattice is much more stable, either returning to its original state when perturbed, or resulting in a structure with an O-O dimer that is much higher in energy. This can be explained by the mixed redox process for Li<sub>2</sub>IrO<sub>3</sub>, which is also shown from the calculated magnetic moments. The lack of O-O dimer formation in O1-Li<sub>0.5</sub>IrO<sub>3</sub>provides valuable insight as to why Li<sub>2</sub>IrO<sub>3</sub>does not demonstrate a voltage fade as the battery is cycled, which can be used to design Li-rich battery cathodes with an improved cycling performance. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000466846700004 | Publication Date | 2019-02-21 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2059-8521 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 3 | Open Access | Not_Open_Access: Available from 22.02.2020 | |
Notes | We acknowledge the financial support of FWO-Vlaanderen through project G040116N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:160121 | Serial | 5179 | ||
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Author | Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J. | ||||
Title | Electron Bessel beam diffraction for precise and accurate nanoscale strain mapping | Type | A1 Journal article | ||
Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 114 | Issue | 24 | Pages | 243501 |
Keywords | A1 Journal article; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT) | ||||
Abstract | Strain has a strong effect on the properties of materials and the performance of electronic devices. Their ever shrinking size translates into a constant demand for accurate and precise measurement methods with a very high spatial resolution. In this regard, transmission electron microscopes are key instruments thanks to their ability to map strain with a subnanometer resolution. Here, we present a method to measure strain at the nanometer scale based on the diffraction of electron Bessel beams. We demonstrate that our method offers a strain sensitivity better than 2.5 × 10−4 and an accuracy of 1.5 × 10−3, competing with, or outperforming, the best existing methods with a simple and easy to use experimental setup. | ||||
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Language | Wos | 000472599100019 | Publication Date | 2019-06-17 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 17 | Open Access | OpenAccess |
Notes | Deutsche Forschungsgemeinschaft, RO2057/12-2 ; Fonds Wetenschappelijk Onderzoek, G.0934.17N ; | Approved | Most recent IF: 3.411 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:160119 | Serial | 5181 | ||
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Author | Asapu, R.; Claes, N.; Ciocarlan, R.-G.; Minjauw, M.; Detavernier, C.; Cool, P.; Bals, S.; Verbruggen, S.W. | ||||
Title | Electron Transfer and Near-Field Mechanisms in Plasmonic Gold-Nanoparticle-Modified TiO2Photocatalytic Systems | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS applied nano materials | Abbreviated Journal | ACS Appl. Nano Mater. |
Volume | 2 | Issue | 2 | Pages | 4067-4074 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | The major mechanism responsible for plasmonic enhancement of titanium dioxide photocatalysis using gold nanoparticles is still under contention. This work introduces an experimental strategy to disentangle the significance of the charge transfer and near-field mechanisms in plasmonic photocatalysis. By controlling the thickness and conductive nature of a nanoparticle shell that acts as a spacer layer separating the plasmonic metal core from the TiO2 surface, field enhancement or charge transfer effects can be selectively repressed or evoked. Layer-by-layer and in situ polymerization methods are used to synthesize gold core–polymer shell nanoparticles with shell thickness control up to the sub-nanometer level. Detailed optical and electrical characterization supported by near-field simulation models corroborate the trends in photocatalytic activity of the different systems. This approach mainly points at an important contribution of the enhanced near field. | ||||
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Language | Wos | 000477917700006 | Publication Date | 2019-05-31 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2574-0970 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 32 | Open Access | OpenAccess | |
Notes | This work was supported by Research Foundation Flanders (FWO). P.C. and R-G.C. acknowledge financial support from FWO (Project No. G038215N). N.C. and S.B. acknowledge financial support from the European Research Council (ERC Starting Grant No. 335078-COLOURATOM). | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:160579 | Serial | 5184 | ||
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Author | He, L.; Wang, H.; Chen, L.; Wang, X.; Xie, H.; Jiang, C.; Li, C.; Elibol, K.; Meyer, J.; Watanabe, K.; Taniguchi, T.; Wu, Z.; Wang, W.; Ni, Z.; Miao, X.; Zhang, C.; Zhang, D.; Wang, H.; Xie, X. | ||||
Title | Isolating hydrogen in hexagonal boron nitride bubbles by a plasma treatment | Type | A1 Journal article | ||
Year | 2019 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 10 | Issue | 1 | Pages | 2815 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Atomically thin hexagonal boron nitride (h-BN) is often regarded as an elastic film that is impermeable to gases. The high stabilities in thermal and chemical properties allow h-BN to serve as a gas barrier under extreme conditions. Here, we demonstrate the isolation of hydrogen in bubbles of h-BN via plasma treatment. Detailed characterizations reveal that the substrates do not show chemical change after treatment. The bubbles are found to withstand thermal treatment in air, even at 800°C. Scanning transmission electron microscopy investigation shows that the h-BN multilayer has a unique aligned porous stacking nature, which is essential for the character of being transparent to atomic hydrogen but impermeable to hydrogen molecules. In addition, we successfully demonstrated the extraction of hydrogen gases from gaseous compounds or mixtures containing hydrogen element. The successful production of hydrogen bubbles on h-BN flakes has potential for further application in nano/ micro-electromechanical systems and hydrogen storage. | ||||
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Language | Wos | 000473002500004 | Publication Date | 2019-06-27 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 8 | Open Access | Not_Open_Access |
Notes | The work was partially supported by the National Key R&D program (Grant No. 2017YFF0206106), the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB30000000), the National Science Foundation of China (Grant Nos. 51772317, 51302096), the Science and Technology Commission of Shanghai Municipality (Grant No. 16ZR1442700), the Hubei Provincial Natural Science Foundation of China (Grant No. ZRMS2017000370), and the Fundamental Research Funds of Wuhan City (No. 2016060101010075). K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan and JSPS KAKENHI Grant Numbers JP15K21722. C.L. acknowledges support from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grants No. 656378—Interfacial Reactions. L.H. acknowledges financial support from the program of China Scholarships Council (No. 201706160037). H.W. and D.Z. thank Y. Gu, Y. Ma, X. Chen (Shanghai Institute of Technical Physics, Chinese Academy of Sciences) for FTIR spectra measurement. L.C. and L.H. thank Q. Liu and Z. Liu (Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences) for measurement in XPS spectra and mass spectra. | Approved | Most recent IF: 12.124 | ||
Call Number | EMAT @ emat @c:irua:160714 | Serial | 5191 | ||
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Author | Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Batuk, M.; Hadermann, J.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
Title | Effect of zinc oxide modification by indium oxide on microstructure, adsorbed surface species, and sensitivity to CO | Type | A1 Journal article | ||
Year | 2019 | Publication | Frontiers in materials | Abbreviated Journal | |
Volume | 6 | Issue | 6 | Pages | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Additives in semiconductor metal oxides are commonly used to improve sensing behavior of gas sensors. Due to complicated effects of additives on the materials microstructure, adsorption sites and reactivity to target gases the sensing mechanism with modified metal oxides is a matter of thorough research. Herein, we establish the promoting effect of nanocrystalline zinc oxide modification by 1-7 at.% of indium on the sensitivity to CO gas due to improved nanostructure dispersion and concentration of active sites. The sensing materials were synthesized via an aqueous coprecipitation route. Materials composition, particle size and BET area were evaluated using X-ray diffraction, nitrogen adsorption isotherms, high-resolution electron microscopy techniques and EDX-mapping. Surface species of chemisorbed oxygen, OH-groups, and acid sites were characterized by probe molecule techniques and infrared spectroscopy. It was found that particle size of zinc oxide decreased and the BET area increased with the amount of indium oxide. The additive was observed as amorphous indium oxide segregated on agglomerated ZnO nanocrystals. The measured concentration of surface species was higher on In2O3-modified zinc oxide. With the increase of indium oxide content, the sensor response of ZnO/In2O3 to CO was improved. Using in situ infrared spectroscopy, it was shown that oxidation of CO molecules was enhanced on the modified zinc oxide surface. The effect of modifier was attributed to promotion of surface OH-groups and enhancement of CO oxidation on the segregated indium ions, as suggested by DFT in previous work. | ||||
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Language | Wos | 000461540600001 | Publication Date | 2019-03-15 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2296-8016 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 11 | Open Access | OpenAccess | |
Notes | ; Research was supported by the grant from Russian Science Foundation (project No. 18-73-00071). ; | Approved | Most recent IF: NA | ||
Call Number | UA @ admin @ c:irua:158540 | Serial | 5205 | ||
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Author | Kim, Y.; Che, F.; Jo, J.W.; Choi, J.; de Arquer, F.P.G.; Voznyy, O.; Sun, B.; Kim, J.; Choi, M.-J.; Quintero-Bermudez, R.; Fan, F.; Tan, C.S.; Bladt, E.; Walters, G.; Proppe, A.H.; Zou, C.; Yuan, H.; Bals, S.; Hofkens, J.; Roeffaers, M.B.J.; Hoogland, S.; Sargent, E.H. | ||||
Title | A Facet-Specific Quantum Dot Passivation Strategy for Colloid Management and Efficient Infrared Photovoltaics | Type | A1 Journal article | ||
Year | 2019 | Publication | Advanced materials | Abbreviated Journal | Adv Mater |
Volume | 31 | Issue | 31 | Pages | 1805580 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Colloidal nanocrystals combine size- and facet-dependent properties with solution processing. They offer thus a compelling suite of materials for technological applications. Their size- and facet-tunable features are studied in synthesis; however, to exploit their features in optoelectronic devices, it will be essential to translate control over size and facets from the colloid all the way to the film. Larger-diameter colloidal quantum dots (CQDs) offer the attractive possibility of harvesting infrared (IR) solar energy beyond absorption of silicon photovoltaics. These CQDs exhibit facets (nonpolar (100)) undisplayed in small-diameter CQDs; and the materials chemistry of smaller nanocrystals fails consequently to translate to materials for the short-wavelength IR regime. A new colloidal management strategy targeting the passivation of both (100) and (111) facets is demonstrated using distinct choices of cations and anions. The approach leads to narrow-bandgap CQDs with impressive colloidal stability and photoluminescence quantum yield. Photophysical studies confirm a reduction both in Stokes shift (approximate to 47 meV) and Urbach tail (approximate to 29 meV). This approach provides a approximate to 50% increase in the power conversion efficiency of IR photovoltaics compared to controls, and a approximate to 70% external quantum efficiency at their excitonic peak. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000465600000001 | Publication Date | 2019-03-12 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0935-9648 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 19.791 | Times cited | 74 | Open Access | OpenAccess |
Notes | ; Y.K., F.C., J.W.J., and J.C. contributed equally. This work was supported by King Abdullah University of Science and Technology (KAUST, Office of Sponsored Research (OSR), Award No. OSR-2017-CPF-3325) and Ontario Research Fund-Research Excellence program (ORF7-Ministry of Research and Innovation, Ontario Research Fund-Research Excellence Round 7). E.B. gratefully acknowledges financial support by the Research Foundation-Flanders (FWO Vlaanderen). Y.K. received financial support from the DGIST R&D Programs of the Ministry of Science, ICT & Future Planning of Korea (18-ET-01). M.B.J.R. and J.H. acknowledge financial support from the Research Foundation-Flanders (FWO, grants nr ZW15_09-GOH6316 and G.098319N) and the Flemish government through long-term structural funding Methusalem (CASAS2, Meth/15/04). H.Y. acknowledges the Research Foundation-Flanders (FWO) for a postdoctoral fellowship. The authors thank L. Levina, R. Wolowiec, D. Kopilovic, and E. Palmiano for their technical help over the course of this research. ; | Approved | Most recent IF: 19.791 | ||
Call Number | UA @ admin @ c:irua:160392 | Serial | 5239 | ||
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Author | Yuan, S.; Pu, Z.; Zhou, H.; Yu, J.; Amiinu, I.S.; Zhu, J.; Liang, Q.; Yang, J.; He, D.; Hu, Z.; Van Tendeloo, G.; Mu, S. | ||||
Title | A universal synthesis strategy for single atom dispersed cobalt/metal clusters heterostructure boosting hydrogen evolution catalysis at all pH values | Type | A1 Journal article | ||
Year | 2019 | Publication | Nano energy | Abbreviated Journal | Nano Energy |
Volume | 59 | Issue | 59 | Pages | 472-480 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The development of a stable, efficient and economic catalyst for hydrogen evolution reaction (HER) of water splitting is one of the most hopeful approaches to confront the environmental and energy crisis. A two-step method is employed to obtain metal clusters (Ru, N, Pd etc.) combining single cobalt atoms anchored on nitrogen-doped carbon (Ru/Pt/Pd@Co-SAs/N-C). Based on the synergistic effect between Ru clusters and single cobalt atoms, Ru@Co-SAs/N-C exhibits an outstanding HER electrocatalytic activity. Specifically, Ru@Co-SAs/N-C only needs 7 mV overpotential at 10 mA cm(-2) in 1 M KOH solution, which is much better than commercial 20 wt% PVC (40 mV) catalyst. Density functional theory (DFT) calculations further reveal the synergy effect between surface Ru nanoclusters and Co-SAs/N-C toward hydrogen adsorption for HER. Additionally, Ru@CoSAs/N-C also exhibits excellent catalytic ability and durability under acidic and neutral media. The present study opens a new avenue towards the design of metal clusters/single cobalt atoms heterostructures with outstanding performance toward HER and beyond. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000463032200051 | Publication Date | 2019-02-25 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2211-2855 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.343 | Times cited | 33 | Open Access | Not_Open_Access: Available from 01.11.2019 |
Notes | ; S.Y., Z.P. and H.Z. contributed equally to this work. This work was financed by the National Natural Science Foundation of China (Grant No. 51372186, 51672204, 51701146) and the Fundamental Research Funds for the Central Universities (WUT: 2017III055, 2018III039GX, 2018IVA095). We express heartfelt thanks to Prof. Gaoke Zhang for the supply of computational resources in the School of Resources and Environmental Engineering, Wuhan University of Technology. ; | Approved | Most recent IF: 12.343 | ||
Call Number | UA @ admin @ c:irua:159330 | Serial | 5240 | ||
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Author | Becker, M.; Guzzinati, G.; Béché, A.; Verbeeck, J.; Batelaan, H. | ||||
Title | Asymmetry and non-dispersivity in the Aharonov-Bohm effect | Type | A1 Journal article | ||
Year | 2019 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 10 | Issue | 10 | Pages | 1700 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Decades ago, Aharonov and Bohm showed that electrons are affected by electromagnetic potentials in the absence of forces due to fields. Zeilinger's theorem describes this absence of classical force in quantum terms as the “dispersionless” nature of the Aharonov-Bohm effect. Shelankov predicted the presence of a quantum “force” for the same Aharonov-Bohm physical system as elucidated by Berry. Here, we report an experiment designed to test Shelankov's prediction and we provide a theoretical analysis that is intended to elucidate the relation between Shelankov's prediction and Zeilinger's theorem. The experiment consists of the Aharonov-Bohm physical system; free electrons pass a magnetized nanorod and far-field electron diffraction is observed. The diffraction pattern is asymmetric confirming one of Shelankov's predictions and giving indirect experimental evidence for the presence of a quantum “force”. Our theoretical analysis shows that Zeilinger's theorem and Shelankov's result are both special cases of one theorem. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000464338100011 | Publication Date | 2019-04-12 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 12 | Open Access | OpenAccess |
Notes | ; H.B. would like to thank Michael Berry for bringing the presence of a quantum “force” to our attention. A.B., G.G. and J.V. acknowledge support from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. G.G. acknowledges support from the Fonds Wetenschappelijk Onderzoek -Vlaanderen (FWO). M.B. and H.B. acknowledge support by the U.S. National Science Foundation under Grant No. 1602755. ; | Approved | Most recent IF: 12.124 | ||
Call Number | UA @ admin @ c:irua:159341 | Serial | 5241 | ||
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Author | Müller-Caspary, K.; Krause, F.F.; Winkler, F.; Béché, A.; Verbeeck, J.; Van Aert, S.; Rosenauer, A. | ||||
Title | Comparison of first moment STEM with conventional differential phase contrast and the dependence on electron dose | Type | A1 Journal article | ||
Year | 2019 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 203 | Issue | 203 | Pages | 95-104 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | This study addresses the comparison of scanning transmission electron microscopy (STEM) measurements of momentum transfers using the first moment approach and the established method that uses segmented annular detectors. Using an ultrafast pixelated detector to acquire four-dimensional, momentum-resolved STEM signals, both the first moment calculation and the calculation of the differential phase contrast (DPC) signals are done for the same experimental data. In particular, we investigate the ability to correct the segment-based signal to yield a suitable approximation of the first moment for cases beyond the weak phase object approximation. It is found that the measurement of momentum transfers using segmented detectors can approach the first moment measurement as close as 0.13 h/nm in terms of a root mean square (rms) difference in 10 nm thick SrTiO3 for a detector with 16 segments. This amounts to 35% of the rms of the momentum transfers. In addition, we present a statistical analysis of the precision of first moment STEM as a function of dose. For typical experimental settings with recent hardware such as a Medipix3 Merlin camera attached to a probe-corrected STEM, we find that the precision of the measurement of momentum transfers stagnates above certain doses. This means that other instabilities such as specimen drift or scan noise have to be taken into account seriously for measurements that target, e.g., the detection of bonding effects in the charge density. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000465021000013 | Publication Date | 2018-12-30 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 25 | Open Access | OpenAccess |
Notes | ; The direct electron detector (Medipix3 Merlin) was funded by the Hercules fund from the Flemish Government. K. Muller-Caspary acknowledges funding from the Initiative and Network Fund of the Helmholtz Association within the framework of the Helmholtz Young Investigator Group moreSTEM (VH-NG-1317) at Forschungszentrum Julich, Germany. F. F. Krause acknowledges funding from the Central Research Development Fund of the University of Bremen, Germany. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) and the Research Fund of the University of Antwerp. ; | Approved | Most recent IF: 2.843 | ||
Call Number | UA @ admin @ c:irua:160213 | Serial | 5242 | ||
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Author | Yin, C.; Krishnan, D.; Gauquelin, N.; Verbeeck, J.; Aarts, J. | ||||
Title | Controlling the interfacial conductance in LaAlO3/SrTiO3 in 90 degrees off-axis sputter deposition | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical review materials | Abbreviated Journal | |
Volume | 3 | Issue | 3 | Pages | 034002 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report on the fabrication of conducting interfaces between LaAlO3 and SrTiO3 by 90 degrees off-axis sputtering in an Ar atmosphere. At a growth pressure of 0.04 mbar the interface is metallic, with a carrier density of the order of 1 x 10(13) cm(-2) at 3 K. By increasing the growth pressure, we observe an increase of the out-of-plane lattice constants of the LaAlO3 films while the in-plane lattice constants do not change. Also, the low-temperature sheet resistance increases with increasing growth pressure, leading to an insulating interface when the growth pressure reaches 0.10 mbar. We attribute the structural variations to an increase of the La/Al ratio, which also explains the transition from metallic behavior to insulating behavior of the interfaces. Our research shows that the control which is furnished by the Ar pressure makes sputtering as versatile a process as pulsed laser deposition, and emphasizes the key role of the cation stoichiometry of LaAlO3 in the formation of the conducting interface. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000461077100002 | Publication Date | 2019-03-12 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 2475-9953 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.926 | Times cited | 4 | Open Access | Not_Open_Access |
Notes | ; We thank Nikita Lebedev, Aymen Ben Hamida, and Prateek Kumar for useful discussions and Giordano Mattoni, Jun Wang, Vincent Joly, and Hozanna Miro for their technical assistance. We also thank Jean-Marc Triscone and his group for sharing their design of the sputtering system with us. This work is part of the FOM research programme DESCO with Project No. 149, which is (partly) financed by the Netherlands Organisation for Scientific Research (NWO). C.Y. is supported by China Scholarship Council (CSC) with Grant No. 201508110214. N.G., D.K., and J.V. acknowledge financial support from the GOA project “Solarpaint” of the University of Antwerp. ; | Approved | Most recent IF: NA | ||
Call Number | UA @ admin @ c:irua:158547 | Serial | 5243 | ||
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Author | Mefford, J.T.; Kurilovich, A.A.; Saunders, J.; Hardin, W.G.; Abakumov, A.M.; Forslund, R.P.; Bonnefont, A.; Dai, S.; Johnston, K.P.; Stevenson, K.J. | ||||
Title | Decoupling the roles of carbon and metal oxides on the electrocatalytic reduction of oxygen on La1-xSrxCoO3-\delta perovskite composite electrodes | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 21 | Issue | 6 | Pages | 3327-3338 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Perovskite oxides are active room-temperature bifunctional oxygen electrocatalysts in alkaline media, capable of performing the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with lower combined overpotentials relative to their precious metal counterparts. However, their semiconducting nature necessitates the use of activated carbons as conductive supports to generate applicably relevant current densities. In efforts to advance the performance and theory of oxide electrocatalysts, the chemical and physical properties of the oxide material often take precedence over contributions from the conductive additive. In this work, we find that carbon plays an important synergistic role in improving the performance of La1-xSrxCoO3- (0 x 1) electrocatalysts through the activation of O-2 and spillover of radical oxygen intermediates, HO2- and O-2(-), which is further reduced through chemical decomposition of HO2- on the perovskite surface. Through a combination of thin-film rotating disk electrochemical characterization of the hydrogen peroxide intermediate reactions (hydrogen peroxide reduction reaction (HPRR), hydrogen peroxide oxidation reaction (HPOR)) and oxygen reduction reaction (ORR), surface chemical analysis, HR-TEM, and microkinetic modeling on La1-xSrxCoO3- (0 x 1)/carbon (with nitrogen and non-nitrogen doped carbons) composite electrocatalysts, we deconvolute the mechanistic aspects and contributions to reactivity of the oxide and carbon support. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000459584900049 | Publication Date | 2019-01-18 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 1463-9076; 1463-9084 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.123 | Times cited | 5 | Open Access | OpenAccess |
Notes | ; Financial support for this work was provided by the R. A. Welch Foundation (grants F-1529 and F-1319). S. D. was supported as part of the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences. ; | Approved | Most recent IF: 4.123 | ||
Call Number | UA @ admin @ c:irua:158625 | Serial | 5244 | ||
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Author | Gan, Y.; Christensen, D.V.; Zhang, Y.; Zhang, H.; Krishnan, D.; Zhong, Z.; Niu, W.; Carrad, D.J.; Norrman, K.; von Soosten, M.; Jespersen, T.S.; Shen, B.; Gauquelin, N.; Verbeeck, J.; Sun, J.; Pryds, N.; Chen, Y. | ||||
Title | Diluted oxide interfaces with tunable ground states | Type | A1 Journal article | ||
Year | 2019 | Publication | Advanced materials | Abbreviated Journal | Adv Mater |
Volume | 31 | Issue | 10 | Pages | 1805970 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The metallic interface between two oxide insulators, such as LaAlO3/SrTiO3 (LAO/STO), provides new opportunities for electronics and spintronics. However, due to the presence of multiple orbital populations, tailoring the interfacial properties such as the ground state and metal-insulator transitions remains challenging. Here, an unforeseen tunability of the phase diagram of LAO/STO is reported by alloying LAO with a ferromagnetic LaMnO3 insulator without forming lattice disorder and at the same time without changing the polarity of the system. By increasing the Mn-doping level, x, of LaAl1-xMnxO3/STO (0 <= x <= 1), the interface undergoes a Lifshitz transition at x = 0.225 across a critical carrier density of n(c) = 2.8 x 10(13) cm(-2), where a peak T-SC approximate to 255 mK of superconducting transition temperature is observed. Moreover, the LaAl1-xMnxO3 turns ferromagnetic at x >= 0.25. Remarkably, at x = 0.3, where the metallic interface is populated by only d(xy) electrons and just before it becomes insulating, a same device with both signatures of superconductivity and clear anomalous Hall effect (7.6 x 10(12) cm(-2) < n(s) <= 1.1 x 10(13) cm(-2)) is achieved reproducibly. This provides a unique and effective way to tailor oxide interfaces for designing on-demand electronic and spintronic devices. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000460329300004 | Publication Date | 2019-01-14 | |
Series Editor | Series Title | Abbreviated Series Title ![]() |
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Series Volume | Series Issue | Edition | |||
ISSN | 0935-9648 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 19.791 | Times cited | 31 | Open Access | Not_Open_Access |
Notes | ; The authors thank the technical help from J. Geyti. J.R.S. acknowledges the support of the National Basic Research of China (2016YFA0300701, 2018YFA0305704), the National Natural Science Foundation of China (11520101002), and the Key Program of the Chinese Academy of Sciences. N.G., D.K., and J.V. acknowledge funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp, Belgium. ; | Approved | Most recent IF: 19.791 | ||
Call Number | UA @ admin @ c:irua:158553 | Serial | 5245 | ||
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