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Author De wael, A.
Title Model-based quantitative scanning transmission electron microscopy for measuring dynamic structural changes at the atomic scale Type Doctoral thesis
Year 2021 Publication Abbreviated Journal
Volume Issue Pages xiv, 146 p.
Keywords Doctoral thesis; Electron microscopy for materials research (EMAT)
Abstract Nanomaterialen kunnen uiterst interessante eigenschappen vertonen voor een verscheidenheid aan veelbelovende toepassingen, gaande van zonnecrème tot batterijen voor elektrische auto’s. Een nanometer is een miljard keer kleiner dan een meter. Op deze schaal kunnen de materiaaleigenschappen volledig verschillen van bulkmaterialen op grotere schaal. Bovendien hangen de eigenschappen van nanomaterialen sterk af van hun exacte grootte en vorm. Kleine verschillen in de posities van de atomen, in de grootte-orde van een picometer (nog eens duizend maal kleiner dan een nanometer), kunnen de fysische eigenschappen al drastisch beïnvloeden. Daarom is een betrouwbare kwantificering van de atomaire structuur van kritisch belang om de evolutie naar materiaalontwerp mogelijk te maken en inzicht te verwerven in de relatie tussen de fysische eigenschappen en de structuur van nanomaterialen. Daarnaast kan de atomaire structuur van nanomaterialen ook veranderen in de loop van de tijd ten gevolge van verschillende fysische processen. Het onderzoek dat in deze thesis gepresenteerd wordt, maakt het mogelijk om de dynamische structuurveranderingen van nanomaterialen betrouwbaar te kwantificeren op atomaire schaal door gebruik te maken van raster transmissie elektronenmicroscopie (STEM). Ik heb dit gerealiseerd door methodes te ontwikkelen waarmee ik het aantal atomen “achter elkaar” kan tellen in elke atoomkolom van een nanomateriaal, en dit op basis van beelden opgenomen met een elektronenmicroscoop. Een belangrijk verschil met telmethodes voor de analyse van een enkel beeld is het schatten van de kans dat een atoomkolom atomen zal verliezen of bijkrijgen van het ene naar het andere beeld in de tijdreeks. Deze kwantitatieve methode kan het ontrafelen van de tijdsafhankelijke structuur-eigenschappen relatie van een nanomateriaal mogelijk maken, wat uiteindelijk kan leiden tot efficiënter design en productie van nanomaterialen voor innovatieve toepassingen.
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Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:179514 Serial 6870
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Author Safdel, A.; Zarei-Hanzaki, A.; Abedi, H.R.; Pourbabak, S.; Schryvers, D.; Basu, R.
Title Asymmetrical superelastic behavior of thermomechanically processed semi-equiatomic NiTi alloy in tensile and compressive modes of deformation Type A1 Journal article
Year 2021 Publication Journal Of Alloys And Compounds Abbreviated Journal J Alloy Compd
Volume 878 Issue Pages 160443
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In the present work two different cold working and annealing schemes were utilized, and the asymmetric superelastic response of thermomechanically processed materials were then assessed through cyclic tensile and compressive modes of deformation. The values of transformation stress, transformation strain, and pseudoelastic strain were measured for each treated and solutionized specimens and the asymmetric response was compared. In the solution annealed state, the difference of these parameters at different deformation modes was negligible due to the weak texture of the material, while for thermomechanically treated ones, development of specific deformation and recrystallization texture components was identified to be one of the underlying reasons of intensified asymmetry. The evolved substructure during the thermomechanical processing also played a substantial role in determining the asymmetric response. The presence of fine grains and dense dislocation substructure could hinder the movement of the transformation front, thus limiting the range of transformation. In tensile mode, the transformation stress was lower, but higher transformation strain was achieved, which was discussed relying on the slip activity in specified oriented grains. The lower transformation strain in compression mode led to lower pseudoelastic strain due to the narrow transformation range which finally degraded superelastic response of the material. (C) 2021 Elsevier B.V. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000660477400005 Publication Date 2021-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-8388 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.133 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.133
Call Number (up) UA @ admin @ c:irua:179564 Serial 6855
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Author Feng, H.L.; Kang, C.-J.; Manuel, P.; Orlandi, F.; Su, Y.; Chen, J.; Tsujimoto, Y.; Hadermann, J.; Kotliar, G.; Yamaura, K.; McCabe, E.E.; Greenblatt, M.
Title Antiferromagnetic order breaks inversion symmetry in a metallic double perovskite, Pb₂NiOsO₆ Type A1 Journal article
Year 2021 Publication Chemistry Of Materials Abbreviated Journal Chem Mater
Volume 33 Issue 11 Pages 4188-4195
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A polycrystalline sample of Pb2NiOsO6 was synthesized under high-pressure (6 GPa) and high-temperature (1575 K) conditions. Pb2NiOsO6 crystallizes in a monoclinic double perovskite structure with a centrosymmetric space group P2(1)/n at room temperature. Pb2NiOsO6 is metallic down to 2 K and shows a single antiferromagnetic (AFM) transition at T-N = 58 K. Pb2NiOsO6 is a new example of a metallic and AFM oxide with three-dimensional connectivity. Neutron powder diffraction and first-principles calculation studies indicate that both Ni and Os moments are ordered below T-N and the AFM magnetic order breaks inversion symmetry. This loss of inversion symmetry driven by AFM order is unusual in metallic systems, and the 3d-Sd double-perovskite oxides represent a new class of noncentrosymmetric AFM metallic oxides.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000661521800032 Publication Date 2021-05-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756; 1520-5002 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 9.466
Call Number (up) UA @ admin @ c:irua:179679 Serial 6854
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Author Coeck, R.; Meeprasert, J.; Li, G.; Altantzis, T.; Bals, S.; Pidko, E.A.; De Vos, D.E.
Title Gold and silver-catalyzed reductive amination of aromatic carboxylic acids to benzylic amines Type A1 Journal article
Year 2021 Publication Acs Catalysis Abbreviated Journal Acs Catal
Volume 11 Issue 13 Pages 7672-7684
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract The reductive amination of benzoic acid and its derivatives would be an effective addition to current synthesis methods for benzylamine. However, with current technology it is very difficult to keep the aromaticity intact when starting from benzoic acid, and salt wastes are often generated in the process. Here, we report a heterogeneous catalytic system for such a reductive amination, requiring solely H-2 and NH3 as the reactants. The Ag/TiO2 or Au/TiO2 catalysts can be used multiple times, and very little noble metal is required, only 0.025 mol % Au. The catalysts are bifunctional: the support catalyzes the dehydration of both the ammonium carboxylate to the amide and of the amide to the nitrile, while the sites at the metal-support interface promote the hydrogenation of the in situ generated nitrile. Yields of up to 92% benzylamine were obtained.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000670659900005 Publication Date 2021-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2155-5435 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 10.614 Times cited 16 Open Access OpenAccess
Notes R.C. thanks the FWO for his SB PhD fellowship. D.E.D.V. acknowledges FWO for research project funding, as well as KU Leuven for funding in the Metusalem program Casas. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO). T.A. acknowledges funding from the University of Antwerp Research fund (BOF). E.A.P. acknowledges the support from the European Research Council (ERC Consolidator grant #725686 DeliCAT). J.M. acknowledges financial support through the Royal Thai Government Scholarship. DFT calculations on SURFsara supercomputer facilities were performed with support from the Netherlands Organization for Scientific Research (NWO).; sygmaSB Approved Most recent IF: 10.614
Call Number (up) UA @ admin @ c:irua:179851 Serial 6840
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Author Choukroun, D.; Pacquets, L.; Li, C.; Hoekx, S.; Arnouts, S.; Baert, K.; Hauffman, T.; Bals, S.; Breugelmans, T.
Title Mapping composition–selectivity relationships of supported sub-10 nm Cu–Ag nanocrystals for high-rate CO₂ electroreduction Type A1 Journal article
Year 2021 Publication Acs Nano Abbreviated Journal Acs Nano
Volume 15 Issue 9 Pages 14858-14872
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Colloidal Cu–Ag nanocrystals measuring less than 10 nm across are promising candidates for integration in hybrid CO2 reduction reaction (CO2RR) interfaces, especially in the context of tandem catalysis and selective multicarbon (C2–C3) product formation. In this work, we vary the synthetic-ligand/copper molar ratio from 0.1 to 1.0 and the silver/copper atomic ratio from 0 to 0.7 and study the variations in the nanocrystals’ size distribution, morphology and reactivity at rates of ≥100 mA cm–2 in a gas-fed recycle electrolyzer operating under neutral to mildly basic conditions (0.1–1.0 M KHCO3). High-resolution electron microscopy and spectroscopy are used in order to characterize the morphology of sub-10 nm Cu–Ag nanodimers and core–shells and to elucidate trends in Ag coverage and surface composition. It is shown that Cu–Ag nanocrystals can be densely dispersed onto a carbon black support without the need for immediate ligand removal or binder addition, which considerably facilitates their application. Although CO2RR product distribution remains an intricate function of time, (kinetic) overpotential and processing conditions, we nevertheless conclude that the ratio of oxygenates to hydrocarbons (which depends primarily on the initial dispersion of the nanocrystals and their composition) rises 3-fold at moderate Ag atom % relative to Cu NCs-based electrodes. Finally, the merits of this particular Cu–Ag/C system and the recycling reactor employed are utilized to obtain maximum C2–C3 partial current densities of 92–140 mA cm–2 at −1.15 VRHE and liquid product concentrations in excess of 0.05 wt % in 1 M KHCO3 after short electrolysis periods.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000703553600082 Publication Date 2021-08-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 25 Open Access OpenAccess
Notes D.C. acknowledges Thomas Kenis for configuring the analytical instrumentation (HPLC/GC-FID/ICP-MS), Hannelore Andries for assistance with ICP-MS measurements, and Dr. Saeid Pourbabak and Dr. Tine Derez for assistance with Cu sputtering. L.P. was supported by Research Foundation of Flanders (FWO 1S56920N). S.B. acknowledges financial support from ERC Consolidator grant number 815128 REALNANO. S.B. and T.B. acknowledge financial support from the university research fund (BOF-GOA-PS ID no. 33928).; sygmaSB Approved Most recent IF: 13.942
Call Number (up) UA @ admin @ c:irua:180305 Serial 6844
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Author Peng, X.; Peng, H.; Zhao, K.; Zhang, Y.; Xia, F.; Lyu, J.; Van Tendeloo, G.; Sun, C.; Wu, J.
Title Direct visualization of atomic-scale heterogeneous structure dynamics in MnO₂ nanowires Type A1 Journal article
Year 2021 Publication Acs Applied Materials & Interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 13 Issue 28 Pages 33644-33651
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Manganese oxides are attracting great interest owing to their rich polymorphism and multiple valent states, which give rise to a wide range of applications in catalysis, capacitors, ion batteries, and so forth. Most of their functionalities are connected to transitions among the various polymorphisms and Mn valences. However, their atomic-scale dynamics is still a great challenge. Herein, we discovered a strong heterogeneity in the crystalline structure and defects, as well as in the Mn valence state. The transitions are studied by in situ transmission electron microscopy (TEM), and they involve a complex ordering of [MnO6] octahedra as the basic building tunnels. MnO2 nanowires synthesized using solution-based hydrothermal methods usually exhibit a large number of multiple polymorphism impurities with different tunnel sizes. Upon heating, MnO2 nanowires undergo a series of stoichiometric polymorphism changes, followed by oxygen release toward an oxygen-deficient spinel and rock-salt phase. The impurity polymorphism exhibits an abnormally high stability with interesting small-large-small tunnel size transition, which is attributed to a preferential stabilizer (K+) concentration, as well as a strong competition of kinetics and thermodynamics. Our results unveil the complicated intergrowth of polymorphism impurities in MnO2, which provide insights into the heterogeneous kinetics, thermodynamics, and transport properties of the tunnel-based building blocks.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000677540900101 Publication Date 2021-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 7.504
Call Number (up) UA @ admin @ c:irua:180450 Serial 6861
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Author Gonzalez-Nelson, A.; Mula, S.; Simenas, M.; Balciunas, S.; Altenhof, A.R.; Vojvodin, C.S.; Canossa, S.; Banys, J.; Schurko, R.W.; Coudert, F.-X.; van der Veen, M.A.
Title Emergence of coupled rotor dynamics in metal-organic frameworks via tuned steric interactions Type A1 Journal article
Year 2021 Publication Journal Of The American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 143 Issue 31 Pages 12053-12062
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The organic components in metal-organic frameworks (MOFs) are unique: they are embedded in a crystalline lattice, yet, as they are separated from each other by tunable free space, a large variety of dynamic behavior can emerge. These rotational dynamics of the organic linkers are especially important due to their influence over properties such as gas adsorption and kinetics of guest release. To fully exploit linker rotation, such as in the form of molecular machines, it is necessary to engineer correlated linker dynamics to achieve their cooperative functional motion. Here, we show that for MIL-53, a topology with closely spaced rotors, the phenylene functionalization allows researchers to tune the rotors' steric environment, shifting linker rotation from completely static to rapid motions at frequencies above 100 MHz. For steric interactions that start to inhibit independent rotor motion, we identify for the first time the emergence of coupled rotation modes in linker dynamics. These findings pave the way for function-specific engineering of gear-like cooperative motion in MOFs.
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Publisher Place of Publication Editor
Language Wos 000684581100022 Publication Date 2021-07-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 13.858
Call Number (up) UA @ admin @ c:irua:180504 Serial 6867
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Author Dey, A.; Ye, J.; De, A.; Debroye, E.; Ha, S.K.; Bladt, E.; Kshirsagar, A.S.; Wang, Z.; Yin, J.; Wang, Y.; Quan, L.N.; Yan, F.; Gao, M.; Li, X.; Shamsi, J.; Debnath, T.; Cao, M.; Scheel, M.A.; Kumar, S.; Steele, J.A.; Gerhard, M.; Chouhan, L.; Xu, K.; Wu, X.-gang; Li, Y.; Zhang, Y.; Dutta, A.; Han, C.; Vincon, I.; Rogach, A.L.; Nag, A.; Samanta, A.; Korgel, B.A.; Shih, C.-J.; Gamelin, D.R.; Son, D.H.; Zeng, H.; Zhong, H.; Sun, H.; Demir, H.V.; Scheblykin, I.G.; Mora-Sero, I.; Stolarczyk, J.K.; Zhang, J.Z.; Feldmann, J.; Hofkens, J.; Luther, J.M.; Perez-Prieto, J.; Li, L.; Manna, L.; Bodnarchuk, M., I; Kovalenko, M., V; Roeffaers, M.B.J.; Pradhan, N.; Mohammed, O.F.; Bakr, O.M.; Yang, P.; Muller-Buschbaum, P.; Kamat, P., V; Bao, Q.; Zhang, Q.; Krahne, R.; Galian, R.E.; Stranks, S.D.; Bals, S.; Biju, V.; Tisdale, W.A.; Yan, Y.; Hoye, R.L.Z.; Polavarapu, L.
Title State of the art and prospects for Halide Perovskite Nanocrystals Type A1 Journal article
Year 2021 Publication Acs Nano Abbreviated Journal Acs Nano
Volume 15 Issue 7 Pages 10775-10981
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Metal-halide perovskites have rapidly emerged as one of the most promising materials of the 21st century, with many exciting properties and great potential for a broad range of applications, from photovoltaics to optoelectronics and photocatalysis. The ease with which metal-halide perovskites can be synthesized in the form of brightly luminescent colloidal nanocrystals, as well as their tunable and intriguing optical and electronic properties, has attracted researchers from different disciplines of science and technology. In the last few years, there has been a significant progress in the shape-controlled synthesis of perovskite nanocrystals and understanding of their properties and applications. In this comprehensive review, researchers having expertise in different fields (chemistry, physics, and device engineering) of metal-halide perovskite nanocrystals have joined together to provide a state of the art overview and future prospects of metal-halide perovskite nanocrystal research.
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Language Wos 000679406500006 Publication Date 2021-06-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 538 Open Access OpenAccess
Notes E.D. and J.H. acknowledge financial support from the Research FoundationFlanders (FWO Grant Nos. S002019N, G.0B39.15, G.0B49.15, G.0962.13, G098319N, and ZW15_09-GOH6316), the Research Foundation Flanders postdoctoral fellowships to J.A.S. and E.D. (FWO Grant Nos. 12Y7218N and 12O3719N, respectively), Approved Most recent IF: 13.942
Call Number (up) UA @ admin @ c:irua:180553 Serial 6846
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Author Abakumov, A.M.; Li, C.; Boev, A.; Aksyonov, D.A.; Savina, A.A.; Abakumova, T.A.; Van Tendeloo, G.; Bals, S.
Title Grain boundaries as a diffusion-limiting factor in lithium-rich NMC cathodes for high-energy lithium-ion batteries Type A1 Journal article
Year 2021 Publication ACS applied energy materials Abbreviated Journal
Volume 4 Issue 7 Pages 6777-6786
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract High-energy lithium-rich layered transition metal oxides are capable of delivering record electrochemical capacity and energy density as positive electrodes for Li-ion batteries. Their electrochemical behavior is extremely complex due to sophisticated interplay between crystal structure, electronic structure, and defect structure. Here we unravel an extra level of this complexity by revealing that the most typical representative Li1.2Ni0.13Mn0.54Co0.13O2 material, prepared by a conventional coprecipitation technique with Na2CO3 as a precipitating agent, contains abundant coherent (001) grain boundaries with a Na-enriched P2-structured block due to segregation of the residual sodium traces. The trigonal prismatic oxygen coordination of Na triggers multiple nanoscale twinning, giving rise to incoherent (104) boundaries. The cationic layers at the (001) grain boundaries are filled with transition metal cations being Mn-depleted and Co-enriched; this makes them virtually not permeable for the Li+ cations, and therefore they negatively influence the Li diffusion in and out of the spherical agglomerates. These results demonstrate that besides the mechanisms intrinsic to the crystal and electronic structure of Li-rich cathodes, their rate capability might also be depreciated by peculiar microstructural aspects. Dedicated engineering of grain boundaries opens a way for improving inherently sluggish kinetics of these materials.
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Language Wos 000678382900042 Publication Date 2021-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2574-0962 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access OpenAccess
Notes We thank Dr. M. V. Berekchiian (MSU) for assisting in ICPMS measurements. We acknowledge Russian Science Foundation (Grant 20-43-01012) and Research Foundation Flanders (FWO Vlaanderen, Project No. G0F1320N) for financial support. Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:180556 Serial 6841
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Author Skorikov, A.; Heyvaert, W.; Albrecht, W.; Pelt, D.M.; Bals, S.
Title EMAT Simulated 3D Nanoparticle Structures Dataset Type Dataset
Year 2021 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; Electron microscopy for materials research (EMAT)
Abstract This dataset contains 1000 simulated nanoparticle-like 3D structures and noisy EDX-like elemental maps based on them. These data are intended to be used for quantitative analysis of data processing methods in (EDX) tomography of nanoparticles and training the data-driven approaches for these tasks. The dataset is structured as follows: voxel_data/clean 3D voxel grid representation of the simulated nanoparticles. Voxel intensities are adjusted so that the total intensity equals 103. All 3D structures have unique identifiers in 0..999 range. The data derived from a 3D structure preserves this unique identifier. sinograms/clean Tilt series of projection images obtained from the corresponding 3D structures over an angular range of -75..75 degrees with a tilt step of 10 degrees to simulate a typical tilt series used in EDX tomography. Total intensity in each projection image equals 103. sinograms/noisy Tilt series of projection images corrupted with Poisson noise and an additional spatially uniform background noise. projections/clean Projection images extracted from the clean tilt series at 0 degrees tilt angle. projections/noisy Projection images extracted from the noisy tilt series at 0 degrees tilt angle. images/clean Visualizations of the clean projections as PNG images with the intensity range adjusted to 0..255 images/noisy Visualizations of the noisy projections as PNG images with the intensity range adjusted to 0..255
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Language Wos Publication Date
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ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:180615 Serial 6838
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Author Guzzinati, G.; Das, P.P.; Zompra, A., A.; Nicopoulos, S.; Verbeeck, J.
Title Electron energy loss spectra of several organic compounds Type Dataset
Year 2020 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; Electron microscopy for materials research (EMAT)
Abstract We placed crystals of different compounds to explore the possibility of fingerprinting them through EELS. Here are representative datasets of 7 different compounds: b-cyclodextrin hexacarboxy cyclohexane tannin TH-15 peptide TH-27 peptide two different forms of piroxicam The datasets were collected at EMAT, using a monochromated FEI Titan3 TEM, within the scope of an EUSMI request. More information as well as analysis methodologies adopted for the data are detailed in the paper: Das et al. “Reliable Characterization of Organic & Pharmaceutical Compounds with High Resolution Monochromated EEL Spectroscopy”, Polymers 2020, 12(7), 1434.
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Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:180654 Serial 6866
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Author Samaeeaghmiyoni, V.; Cordier, P.; Demouchy, S.; Bollinger, C.; Gasc, J.; Mussi, A.; Schryvers, D.; Idrissi, H.
Title Research data supporting for Stress-induced amorphization triggers deformation in the lithospheric mantle Type Dataset
Year 2020 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; Electron microscopy for materials research (EMAT)
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Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:180668 Serial 6881
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Author Vervaet, B.A.; Nast, C.C.; Jayasumana, C.; Schreurs, G.; Roels, F.; Herath, C.; Kojc, N.; Samaee, V.; Rodrigo, S.; Gowrishankar, R.
Title Chronic interstitial nephritis in agricultural communities : a toxin-induced proximal tubular nephropathy Type A1 Journal article
Year 2020 Publication European Medical Journal : Nephrology Abbreviated Journal
Volume 8 Issue 1 Pages 40-42
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Pathophysiology
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Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
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ISSN 2053-4248 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:180862 Serial 6858
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Author Velazco Torrejón, A.
Title Alternative scan strategies for high resolution STEM imaging Type Doctoral thesis
Year 2021 Publication Abbreviated Journal
Volume Issue Pages 131 p.
Keywords Doctoral thesis; Electron microscopy for materials research (EMAT)
Abstract Currently, a large variety of materials are studied by transmission electron microscopy (TEM) as it offers the possibility to perform structural and elemental analysis at a local scale. Relatively recent advances in aberration correctors and electron sources allow the instrument to achieve atomic resolution. Along with these advances, a state-of-the-art technology has been reached in TEM. However, the instrument is far from being perfect and imperfections or external sources can make the interpretation of information troublesome. Environmental factors such as acoustic and mechanical vibrations, temperature fluctuations, etc., can induce sample drift and create image distortions. These distortions are enhanced in scanning operation because of the serial acquisition of the information, which are more apparent at atomic resolution as small field of views are imaged. In addition, scanning distortions are induced due to the finite time response of the scan coils. These types of distortions would reduce precision in atomic-scale strain analysis, for instance, in semiconductors. Most of the efforts to correct these distortions are focused on data processing techniques post-acquisition. Another limitation in TEM is beam damage effects. Beam damage arises because of the energy transferred to the sample in electron-sample interactions. In scanning TEM, at atomic resolution, the increased electron charge density (electron dose) carried on a sub-Å size electron probe may aggravate beam damage effects. Soft materials such as zeolites, organic, biological materials, etc., can be destroyed under irradiation limiting the amount of information that can be acquired. Current efforts to circumvent beam damage are mostly based on low electron dose acquisitions and data processing methods to maximize the signal at low dose conditions. In this thesis, a different approach is given to address drift and scanning distortions, as well as beam damage effects. Novel scan strategies are proposed for that purpose, which are shown to substantially overcome these issues compared to the standard scan method in TEM.
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ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:180973 Serial 6852
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Author Roegiers, J.
Title Development of combined photocatalytic and active carbon fiber technology for indoor air purification based on Multiphysics models Type Doctoral thesis
Year 2021 Publication Abbreviated Journal
Volume Issue Pages XXX, 197 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract Exposure to volatile organic compounds (VOCs) remains a major public health concern. Indoor VOC concentrations typically far exceed outdoor levels due to a variety of emission sources and the stringent insulation measures that are imposed today. Many attempts have been made to use photocatalysis for indoor air purification. In an ideal situation, photocatalysis is capable of complete mineralization of VOCs to H2O and CO2, without any byproduct formation. Moreover, the process can take place at standard atmospheric conditions, i.e. ambient temperature and atmospheric pressure. However, successful exploitation is still impeded due to low conversion efficiency, significant pressure loss (and hence a high energy consumption) and byproduct formation. In the first part of this thesis an attempt was made to tackles these problems by designing a novel type of photocatalytic (PCO) reactor. The PCO device consists of a cylindrical vessel filled with TiO2-coated glass tubes and equipped with UV fluorescence lamps. It was investigated in terms of fluid dynamics, coating properties, UV-light distribution and photocatalytic activity. Experimental data was later used to develop and calibrate a Multiphysics model. The model proved to be a useful tool for designing and upscaling the PCO reactor. Consequently, an optimized prototype reactor was constructed and tested according the CEN-EN-16846-1 standard for VOC removal. Although the prototype showed promising results for lab-scale conditions, it struggled with byproduct formation when purifying ppb-level VOCs. In the second part of this thesis, activated carbon adsorption was investigated in order to combine it with photocatalysis. Activated carbon fiber was opted for its fast kinetics, high adsorption capacity and thermo-electrical regeneration. The filter was studied in detail regarding the adsorption of polar and apolar VOCs at indoor air concentration levels and regeneration capabilities. Experimental data was used to develop a Multiphysics model for activated carbon adsorption as well. Consequently, a novel type of ACF filter was developed using the Multiphysics model, which was equipped with electrodes in the tips of the pleats for effective thermal regeneration. In the last part, the combination of both ACF and PCO was studied using a realistic case study. Based on the Multiphysics model, the feasibility of a so-called hybrid air purification device could be investigated. The Multiphysics model shows promising results for this hybrid PCO-ACF system and hence, a demo setup was constructed for future research.
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Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:181137 Serial 6860
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Author Pedrazo Tardajos, A.
Title Advanced graphene supports for 3D in situ transmission electron microscopy Type Doctoral thesis
Year 2021 Publication Abbreviated Journal
Volume Issue Pages 247 p.
Keywords Doctoral thesis; Electron microscopy for materials research (EMAT)
Abstract Transmission electron microscopy (TEM) is an ideal tool to investigate nanomaterials. The information from TEM experiments allows us to link the structure and composition of nanomaterials to their intrinsic physical properties. However, despite the significant evolution of the TEM field during the last two decades, major progress is still possible through the development of optimal TEM techniques and supports. The results presented in this thesis focus on the optimization of sample supports and their application. Among the different options, graphene has previously been reported as useful sample support for electron microscopy due to its unparalleled properties, for example, it is the thinnest known support and provides a protective effect to the sample under investigation. Unfortunately, commercial graphene grids show poor quality, in terms of intactness and cleanness, inhibiting their wide application within the field. Therefore, this thesis focuses on the application of optimized graphene TEM grids, obtained by transferring high quality graphene using an advanced procedure. This improvement on the transfer has enabled the visualization of materials with low contrast and high sensitivity towards the electron beam, such as surface ligands capping gold nanoparticles or metal halide perovskites. Furthermore, the implemented protocol is not only of interest for conventional TEM grids but also a major benefit for in situ TEM studies, where the sample is investigated in real time under certain stimuli. Hence, the same graphene transfer technology can be also applied to advanced in situ MEMS holders dedicated for both heating and gas experiments, where the thickness and insulating nature of the silicon nitride (Si3N4) support may hamper some applications. By engineering periodic arrays of holes in their Si3N4 membrane by focused ion beam, onto which the graphene is transferred, it has been possible to get proof-of-concept 3D in situ investigations of heat-induced morphological and compositional transformations of complex nanosystems. As an example, it has enabled the investigation of the possible phase-transition of metal halide perovskites upon heating using 2D and 3D structural characterization. Moreover, it has allowed the study of in situ three-dimensional nanoparticle dynamics during gas phase catalysis as well as the first steps that would lead towards the design and creation of the first Graphene Gas Cell. Consequently, implementation of the advanced graphene transfer technology described in this thesis is envisaged to impact a broad range of future experiments.
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Corporate Author Thesis
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Language Wos Publication Date
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Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:181143 Serial 6836
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Author Bae, J.; Cichocka, M.O.; Zhang, Y.; Bacsik, Z.; Bals, S.; Zou, X.; Willhammar, T.; Hong, S.B.
Title Phase transformation behavior of a two-dimensional zeolite Type A1 Journal article
Year 2019 Publication Angewandte Chemie: international edition in English Abbreviated Journal
Volume 58 Issue 30 Pages 10230-10235
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Understanding the molecular-level mechanisms of phase transformation in solids is of fundamental interest for functional materials such as zeolites. Two-dimensional (2D) zeolites, when used as shape-selective catalysts, can offer improved access to the catalytically active sites and a shortened diffusion length in comparison with their 3D analogues. However, few materials are known to maintain both their intralayer microporosity and structure during calcination for organic structure-directing agent (SDA) removal. Herein we report that PST-9, a new 2D zeolite which has been synthesized via the multiple inorganic cation approach and fulfills the requirements for true layered zeolites, can be transformed into the small-pore zeolite EU-12 under its crystallization conditions through the single-layer folding process, but not through the traditional dissolution/recrystallization route. We also show that zeolite crystal growth pathway can differ according to the type of organic SDAs employed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000476452700030 Publication Date 2019-05-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access OpenAccess
Notes We acknowledge financial support from National Creative Research Initiative Program (2012R1A3A-2048833) through the National Research Foundation of Korea, the National Research Council of Science & Technology (CRC-14-1-KRICT) grant by the Korea government (MSIP), the Swedish Research Council (2017-04321), and the Knut and Alice Wallenberg Foundation (KAW) through the project grant 3DEM-NATUR (2012.0112). T.W. acknowledges an international postdoc grant from the Swedish Research Council (2014-06948). Approved no
Call Number (up) UA @ admin @ c:irua:181233 Serial 6878
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Author Bouwmeester, R.L.; de Hond, K.; Gauquelin, N.; Verbeeck, J.; Koster, G.; Brinkman, A.
Title Stabilization of the perovskite phase in the Y-Bi-O system by using a BaBiO₃ buffer layer Type A1 Journal article
Year 2019 Publication Physica status solidi: rapid research letters Abbreviated Journal
Volume 13 Issue 7 Pages 1800679
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A topological insulating phase has theoretically been predicted for the thermodynamically unstable perovskite phase of YBiO3. Here, it is shown that the crystal structure of the Y-Bi-O system can be controlled by using a BaBiO3 buffer layer. The BaBiO3 film overcomes the large lattice mismatch of 12% with the SrTiO3 substrate by forming a rocksalt structure in between the two perovskite structures. Depositing an YBiO3 film directly on a SrTiO3 substrate gives a fluorite structure. However, when the Y-Bi-O system is deposited on top of the buffer layer with the correct crystal phase and comparable lattice constant, a single oriented perovskite structure with the expected lattice constants is observed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000477671800005 Publication Date 2019-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6254 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 11 Open Access
Notes The work at the University of Twente is financially supported by NWO through a VICI grant. N.G. and J.V. acknowledge financial support from the GOA project “Solarpaint” of the University of Antwerp. The microscope used for this experiment has been partially financed by the Hercules Fund from the Flemish Government. L. Ding is acknowledge for his help with the GPA analysis. Approved no
Call Number (up) UA @ admin @ c:irua:181236 Serial 6889
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Author Ma, R.; He, Y.; Feng, J.; Hu, Z.-Y.; Van Tendeloo, G.; Li, D.
Title A facile synthesis of Ag@PdAg core-shell architecture for efficient purification of ethene feedstock Type A1 Journal article
Year 2019 Publication Journal of catalysis Abbreviated Journal
Volume 369 Issue Pages 440-449
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Precise control of elemental configurations within multimetallic nanoparticles could enable access to functional nanomaterials with significant performance benefits. Here, we present a one-pot synthesis of supported Ag@PdAg core-shell catalyst with an ordered PdAg alloy shell and an Ag core. Both the relative reduction potential and ratio of metal precursors are essential for this synthesis strategy. The distinguished properties of Ag@PdAg, particularly the electronic structure, indicates the existence of electron modification not only between Pd and Ag on PdAg shell, but between Ag core and alloy shell. The Ag@PdAg catalyst displays 97% ethene yield in the partial hydrogenation of acetylene, which is 2.0 and 8.1 times that of over PdAg alloy and pure Pd catalysts, and this is the most selective catalyst reported to data under industrial evaluation conditions. Moreover, this core-shell structure exhibits preferable stability with comparison to PdAg alloy catalyst. The facile synthesis of core-shell architecture with alloy shell structure provides a new platform for efficient catalytic transfer of chemical resource. (C) 2018 Elsevier Inc. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000460711700045 Publication Date 2018-12-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9517 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number (up) UA @ admin @ c:irua:181261 Serial 6848
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Author Liang, Q.; Yang, D.; Xia, F.; Bai, H.; Peng, H.; Yu, R.; Yan, Y.; He, D.; Cao, S.; Van Tendeloo, G.; Li, G.; Zhang, Q.; Tang, X.; Wu, J.
Title Phase-transformation-induced giant deformation in thermoelectric Ag₂Se semiconductor Type A1 Journal article
Year 2021 Publication Advanced Functional Materials Abbreviated Journal Adv Funct Mater
Volume Issue Pages 2106938
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In most semiconducting metal chalcogenides, a large deformation is usually accompanied by a phase transformation, while the deformation mechanism remains largely unexplored. Herein, a phase-transformation-induced deformation in Ag2Se is investigated by in situ transmission electron microscopy, and a new ordered high-temperature phase (named as alpha '-Ag2Se) is identified. The Se-Se bonds are folded when the Ag+-ion vacancies are ordered and become stretched when these vacancies are disordered. Such a stretch/fold of the Se-Se bonds enables a fast and large deformation occurring during the phase transition. Meanwhile, the different Se-Se bonding states in alpha-, alpha '-, beta-Ag2Se phases lead to the formation of a large number of nanoslabs and the high concentration of dislocations at the interface, which flexibly accommodate the strain caused by the phase transformation. This study reveals the atomic mechanism of the deformation in Ag2Se inorganic semiconductors during the phase transition, which also provides inspiration for understanding the phase transition process in other functional materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000695142800001 Publication Date 2021-09-13
Series Editor Series Title Abbreviated Series Title
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 Open Access Not_Open_Access
Notes Approved Most recent IF: 12.124
Call Number (up) UA @ admin @ c:irua:181527 Serial 6879
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Author Penders, A.; Konstantinovic, M.J.; Van Renterghem, W.; Bosch, R.W.; Schryvers, D.
Title TEM investigation of SCC crack tips in high Si stainless steel tapered specimens Type A1 Journal article
Year 2021 Publication Corrosion Engineering Science And Technology Abbreviated Journal Corros Eng Sci Techn
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The stress corrosion cracking (SCC) mechanism is investigated in high Si duplex stainless steel in a simulated PWR environment based on TEM analysis of FIB-extracted SCC crack tips. The microstructural investigation in the near vicinity of SCC crack tips illustrates a strain-rate dependence in SCC mechanisms. Detailed analysis of the crack tip morphology, that includes crack tip oxidation and surrounding deformation field, indicates the existence of an interplay between corrosion- and deformation-driven failure as a function of the strain rate. Slow strain-rate crack tips exhibit a narrow cleavage failure which can be linked to the film-induced failure mechanism, while rounded shaped crack tips for faster strain rates could be related to the strain-induced failure. As a result, two nominal strain-rate-dependent failure regimes dominated either by corrosion or deformation-driven cracking mechanisms can be distinguished.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000695956400001 Publication Date 2021-09-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1478-422x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.879 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 0.879
Call Number (up) UA @ admin @ c:irua:181533 Serial 6892
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Author Salzmann, B.B.V.; Vliem, J.F.; Maaskant, D.N.; Post, L.C.; Li, C.; Bals, S.; Vanmaekelbergh, D.
Title From CdSe nanoplatelets to quantum rings by thermochemical edge reconfiguration Type A1 Journal article
Year 2021 Publication Chemistry Of Materials Abbreviated Journal Chem Mater
Volume 33 Issue 17 Pages 6853-6859
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The variation in the shape of colloidal semiconductor nanocrystals (NCs) remains intriguing. This interest goes beyond crystallography as the shape of the NC determines its energy levels and optoelectronic properties. While thermodynamic arguments point to a few or just a single shape(s), terminated by the most stable crystal facets, a remarkable variation in NC shape has been reported for many different compounds. For instance, for the well-studied case of CdSe, close-to-spherical quantum dots, rods, two-dimensional nanoplatelets, and quantum rings have been reported. Here, we report how two-dimensional CdSe nanoplatelets reshape into quantum rings. We monitor the reshaping in real time by combining atomically resolved structural characterization with optical absorption and photoluminescence spectroscopy. We observe that CdSe units leave the vertical sides of the edges and recrystallize on the top and bottom edges of the nanoplatelets, resulting in a thickening of the rims. The formation of a central hole, rendering the shape into a ring, only occurs at a more elevated temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000696553600024 Publication Date 2021-08-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756; 1520-5002 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 7 Open Access OpenAccess
Notes Hans Meeldijk is kindly acknowledged for helping with electron microscopy at Utrecht University. B.B.V.S. and D.V. acknowledge the Dutch NWO for financial support via the TOP-ECHO grant no. 715.016.002. D.V. acknowledges financial support from the European ERC Council, ERC Advanced grant 692691 “First Step”. D.V. and L.C.P. acknowledge the Dutch NWO for financial support via the TOP-ECHO grant nr. 718.015.002. S.B acknowledges financial support from the European ERC Council, ERC Consolidator grant 815128. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 731019 (EUSMI). Realnano; sygmaSB Approved Most recent IF: 9.466
Call Number (up) UA @ admin @ c:irua:181550 Serial 6839
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Author Lavor, I.R.; da Costa, D.R.; Covaci, L.; Milošević, M.V.; Peeters, F.M.; Chaves, A.
Title Zitterbewegung of moiré excitons in twisted MoS₂/WSe₂ heterobilayers Type A1 Journal article
Year 2021 Publication Physical review letters Abbreviated Journal
Volume 127 Issue 10 Pages 106801
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract The moire pattern observed in stacked noncommensurate crystal lattices, such as heterobilayers of transition metal dichalcogenides, produces a periodic modulation of their band gap. Excitons subjected to this potential landscape exhibit a band structure that gives rise to a quasiparticle dubbed the moire exciton. In the case of MoS2/WSe2 heterobilayers, the moire trapping potential has honeycomb symmetry and, consequently, the moire exciton band structure is the same as that of a Dirac-Weyl fermion, whose mass can be further tuned down to zero with a perpendicularly applied field. Here we show that, analogously to other Dirac-like particles, the moire exciton exhibits a trembling motion, also known as Zitterbewegung, whose long timescales are compatible with current experimental techniques for exciton dynamics. This promotes the study of the dynamics of moire excitons in van der Waals heterostructures as an advantageous solid-state platform to probe Zitterbewegung, broadly tunable by gating and interlayer twist angle.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000692200800020 Publication Date 2021-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1079-7114 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:181599 Serial 6896
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Author Psilodimitrakopoulos, S.; Orekhov, A.; Mouchliadis, L.; Jannis, D.; Maragkakis, G.M.; Kourmoulakis, G.; Gauquelin, N.; Kioseoglou, G.; Verbeeck, J.; Stratakis, E.
Title Optical versus electron diffraction imaging of Twist-angle in 2D transition metal dichalcogenide bilayers Type A1 Journal article
Year 2021 Publication npj 2D Materials and Applications Abbreviated Journal
Volume 5 Issue 1 Pages 77
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Atomically thin two-dimensional (2D) materials can be vertically stacked with van der Waals bonds, which enable interlayer coupling. In the particular case of transition metal dichalcogenide (TMD) bilayers, the relative direction between the two monolayers, coined as twist-angle, modifies the crystal symmetry and creates a superlattice with exciting properties. Here, we demonstrate an all-optical method for pixel-by-pixel mapping of the twist-angle with a resolution of 0.55(degrees), via polarization-resolved second harmonic generation (P-SHG) microscopy and we compare it with four-dimensional scanning transmission electron microscopy (4D STEM). It is found that the twist-angle imaging of WS2 bilayers, using the P-SHG technique is in excellent agreement with that obtained using electron diffraction. The main advantages of the optical approach are that the characterization is performed on the same substrate that the device is created on and that it is three orders of magnitude faster than the 4D STEM. We envisage that the optical P-SHG imaging could become the gold standard for the quality examination of TMD superlattice-based devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000694849200001 Publication Date 2021-09-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-7132 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access OpenAccess
Notes This research has been co-financed by the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call European R & T Cooperation-Grant Act of Hellenic Institutions that have successfully participated in Joint Calls for Proposals of European Networks ERA NETS (National project code: GRAPH-EYE T8 Epsilon Rho Alpha 2-00009 and European code: 26632, FLAGERA). L.M., G.Ko. and G.Ki. acknowledge funding by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant” (Project No: HFRI-FM17-3034). GKi, S.P. and G.M.M. acknowledge funding from a research co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme “Human Resources Development, Education and Lifelong Learning 2014-2020” in the context of the project “Crystal quality control of two-dimensional materials and their heterostructures via imaging of their non-linear optical properties” (MIS 5050340)“. J.V acknowledges funding from FWO G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund, EU. J.V. and N.G. acknowledge funding from the European Union under the Horizon 2020 programme within a contract for Integrating Activities for Advanced Communities No 823717-ESTEEM3. J.V. N.G. and A.O. acknowledge funding through a GOA project ”Solarpaint" of the University of Antwerp. Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:181610 Serial 6877
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Author Kadu, A.; van Leeuwen, T.; Batenburg, K.J.
Title CoShaRP : a convex program for single-shot tomographic shape sensing Type A1 Journal article
Year 2021 Publication Inverse Problems Abbreviated Journal Inverse Probl
Volume 37 Issue 10 Pages 105005
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We introduce single-shot x-ray tomography that aims to estimate the target image from a single cone-beam projection measurement. This linear inverse problem is extremely under-determined since the measurements are far fewer than the number of unknowns. Moreover, it is more challenging than conventional tomography, where a sufficiently large number of projection angles forms the measurements, allowing for a simple inversion process. However, single-shot tomography becomes less severe if the target image is only composed of known shapes. This paper restricts analysis to target image function that can be decomposed into known compactly supported non-negative-valued functions termed shapes. Hence, the shape prior transforms a linear ill-posed image estimation problem to a non-linear problem of estimating the roto-translations of the shapes. We circumvent the non-linearity by using a dictionary of possible roto-translations of the shapes. We propose a convex program CoShaRP, to recover the dictionary coefficients successfully. CoShaRP relies on simplex-type constraints and can be solved quickly using a primal-dual algorithm. The numerical experiments show that CoShaRP recovers shape stably from moderately noisy measurements.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000691743700001 Publication Date 2021-07-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0266-5611 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.62 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 1.62
Call Number (up) UA @ admin @ c:irua:181617 Serial 6859
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Author Barbiellini, B.; Kuriplach, J.; Saniz, R.
Title Study of rechargeable batteries using advanced spectroscopic and computational techniques Type Editorial
Year 2021 Publication Condensed Matter Abbreviated Journal
Volume 6 Issue 3 Pages 26
Keywords Editorial; Electron microscopy for materials research (EMAT)
Abstract Improving the efficiency and longevity of energy storage systems based on Li- and Na-ion rechargeable batteries presents a major challenge. The main problems are essentially capacity loss and limited cyclability. These effects are due to a hierarchy of factors spanning various length and time scales, interconnected in a complex manner. As a consequence, and in spite of several decades of research, a proper understanding of the ageing process has remained somewhat elusive. In recent years, however, combinations of advanced spectroscopy techniques and first-principles simulations have been applied with success to tackle this problem. In this Special Issue, we are pleased to present a selection of articles that, by precisely applying these methods, unravel key aspects of the reduction-oxidation reaction and intercalation processes. Furthermore, the approaches presented provide improvements to standard diagnostic and characterisation techniques, enabling the detection of possible Li-ion flow bottlenecks causing the degradation of capacity and cyclability.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000699368400001 Publication Date 2021-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2410-3896 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:181630 Serial 6890
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Author Golovachev, I.B.; Mychinko, M.Y.; Volkova, N.E.; Gavrilova, L.Y.; Raveau, B.; Maignan, A.; Cherepanov, V.A.
Title Effect of cobalt content on the properties of quintuple perovskites Sm₂Ba₃Fe₅-xCoxO₁₅-δ Type A1 Journal article
Year 2021 Publication Journal Of Solid State Chemistry Abbreviated Journal J Solid State Chem
Volume 301 Issue Pages 122324
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Quintuple perovskites Sm2Ba3Fe5-xCoxO15-delta = 0.5, 1.0 and 1.5) have been prepared by glycerin-nitrate tech- nique in air. The phase purity was confirmed by XRD. Partial substitution of Co for Fe decreases the oxygen content and thus the mean oxidation state of 3d-metals. It also slightly decreases the thermal expansion coefficient of oxides. Positive value of the Seebeck coefficient confirmed p-type conductivity, though the thermopower decreases as the Co content increases. The temperature dependence of electrical conductivity reveals a maximum at 550-750 degrees C.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000684543700028 Publication Date 2021-06-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 2.299
Call Number (up) UA @ admin @ c:irua:181656 Serial 6864
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Author Wang, X.; Yao, X.; Schryvers, D.; Verlinden, B.; Wang, G.; Zhao, G.; Van Humbeeck, J.; Kustov, S.
Title Anomalous stress-strain behavior of NiTi shape memory alloy close to the border of superelastic window Type A1 Journal article
Year 2021 Publication Scripta Materialia Abbreviated Journal Scripta Mater
Volume 204 Issue Pages 114135
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In this work, we report an anomalous phenomenon on superelastic cycling of NiTi shape memory alloys when deforming at the temperature close to the border of superelastic window. New unexpected effects are found-(i) critical stress for inducing martensite transformation during the second loading cycle is higher than that of the first cycle; ( ii ) the plateau stress of the second cycle decreases to the original level when the strain overcomes the limit of the first cycle; ( iii ) transition from good superelasticity in the first cycle to fully irreversible strain in the second. We propose that defects generated during the first superelastic cycle close to the border of superelastic window impede following stress-induced martensitic transformations, leading to the increase of critical stress beyond yield stress of the B2 matrix, and thus functional fatigue of NiTi alloys. (c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000690441400007 Publication Date 2021-07-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6462 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.747 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.747
Call Number (up) UA @ admin @ c:irua:181658 Serial 6853
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Author Wang, D.; van der Wee, E.B.; Zanaga, D.; Altantzis, T.; Wu, Y.; Dasgupta, T.; Dijkstra, M.; Murray, C.B.; Bals, S.; van Blaaderen, A.
Title Quantitative 3D real-space analysis of Laves phase supraparticles Type A1 Journal article
Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun
Volume 12 Issue 1 Pages 3980
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract 3D real-space analysis of thick nanoparticle crystals is non-trivial. Here, the authors demonstrate the structural analysis of a bulk-like Laves phase by imaging an off-stoichiometric binary mixture of hard-sphere-like nanoparticles in spherical confinement by electron tomography, enabling defect analysis on the single-particle level. Assembling binary mixtures of nanoparticles into crystals, gives rise to collective properties depending on the crystal structure and the individual properties of both species. However, quantitative 3D real-space analysis of binary colloidal crystals with a thickness of more than 10 layers of particles has rarely been performed. Here we demonstrate that an excess of one species in the binary nanoparticle mixture suppresses the formation of icosahedral order in the self-assembly in droplets, allowing the study of bulk-like binary crystal structures with a spherical morphology also called supraparticles. As example of the approach, we show single-particle level analysis of over 50 layers of Laves phase binary crystals of hard-sphere-like nanoparticles using electron tomography. We observe a crystalline lattice composed of a random mixture of the Laves phases. The number ratio of the binary species in the crystal lattice matches that of a perfect Laves crystal. Our methodology can be applied to study the structure of a broad range of binary crystals, giving insights into the structure formation mechanisms and structure-property relations of nanomaterials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000687320200032 Publication Date 2021-06-25
Series Editor Series Title Abbreviated Series Title
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 10 Open Access OpenAccess
Notes M. Hermes is sincerely thanked for providing interactive views of the structures in this work. The authors thank I. Lobato, S. Dussi, L. Filion, E. Boattini, S. Paliwal, B. van der Meer and X. Xie for fruitful discussions. D.W., E.B.v.d.W. and A.v.B. acknowledge partial financial support from the European Research Council under the European Union’s Seventh Framework Program (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. T.D. and M.D. acknowledge financial support from the Industrial Partnership Program, “Computational Sciences for Energy Research” (Grant no. 13CSER025), of the Netherlands Organization for Scientific Research (NWO), which was co-financed by Shell Global Solutions International B.V. S.B. acknowledges financial support from ERC Consolidator Grant No. 815128 REALNANO. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). C.B.M and Y.W. acknowledge support for materials synthesis from the Office of Naval Research Multidisciplinary University Research Initiative Award ONR N00014-18-1-2497. The authors acknowledge EM Square center at Utrecht University for the access to the microscopes.; sygmaSB Approved Most recent IF: 12.124
Call Number (up) UA @ admin @ c:irua:181662 Serial 6845
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Author Prabhakara, V.
Title Strain measurement for semiconductor applications with Raman spectroscopy and Transmission electron microscopy Type Doctoral thesis
Year 2021 Publication Abbreviated Journal
Volume Issue Pages 149 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Scaling down the size of transistors has been a trend for several decades which has led to improved transistor performance, increased transistor density and hence the overall computation power of IC chips. The trend slowed in recent years due to reliability and power consumption issues at the nanoscale. Hence strain is introduced into transistor channels that has beneficial effects on improving the mobility of charge carriers, providing an alternative pathway for enhancing transistor performance. Therefore, monitoring strain is vital for the semiconductor industry. With the recent trend of decreasing device dimensions (FinFETS ~ 10-20nm) and strain modulation being used throughout, industry needs a reliable and fast method as quality control or defect characterisation. Such a universal strain measurement method does not exist, and one relies on a combination of quantitative in-line methods and complex off-line approaches. In this thesis, I investigated TEM and Raman spectroscopy-based methodologies for strain measurement. In terms of TEM methodologies, advancements are made for the STEM moiré imaging, targeting strain spatial resolution enhancement. I introduce advanced quadrature demodulation and phase stepping interferometry applied to STEM moiré that greatly enhances the spatial resolution while providing enhanced field of view and sensitivity for strain measurement. We introduce ways to reduce scan distortions in strain maps using an alternative scan strategy called “Block scanning” and the non-linear regression applied for strain extraction. Prospects for 3D strain analysis using high-resolution tomography is also investigated which gives direct access for the full second order strain tensors calculation. Finally, we compare strain measurements from TEM techniques with inline techniques like Raman spectroscopy. Raman stress measurement involves sensitive identification of the TO and LO phonon peaks. Raman spectrum of strained Ge transistor channel consists of strongly overlapping peaks within the spectral resolution of the spectrometer. Hence, the process of deconvolution of the two peaks is rather challenging. Hence, we explore new polarisation geometries like radially polarised incoming light which was shown to ease the deconvolution problem resulting in improved precision for Raman stress–strain measurements.
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Notes Approved Most recent IF: NA
Call Number (up) UA @ admin @ c:irua:182261 Serial 6847
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