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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.
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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 UA @ admin @ c:irua:181233 Serial (down) 6878
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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.
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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 UA @ admin @ c:irua:181610 Serial (down) 6877
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Author Bartholomeeusen, E.; De Cremer, G.; Kennes, K.; Hammond, C.; Hermans, I.; Lu, J.-B.; Schryvers, D.; Jacobs, P.A.; Roeffaers, M.B.J.; Hofkens, J.; Sels, B.F.; Coutino-Gonzalez, E.
Title Optical encoding of luminescent carbon nanodots in confined spaces Type A1 Journal article
Year 2021 Publication Chemical Communications Abbreviated Journal Chem Commun
Volume 57 Issue 90 Pages 11952-11955
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Stable emissive carbon nanodots were generated in zeolite crystals using near infrared photon irradiation gradually converting the occluded organic template, originally used to synthesize the zeolite crystals, into discrete luminescent species consisting of nano-sized carbogenic fluorophores, as ascertained using Raman microscopy, and steady-state and time-resolved spectroscopic techniques. Photoactivation in a confocal laser fluorescence microscope allows 3D resolved writing of luminescent carbon nanodot patterns inside zeolites providing a cost-effective and non-toxic alternative to previously reported metal-based nanoclusters confined in zeolites, and opens up opportunities in bio-labelling and sensing applications.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000711122000001 Publication Date 2021-10-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-7345; 1364-548x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 6.319
Call Number UA @ admin @ c:irua:184147 Serial (down) 6876
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Author Marteleur, M.; Idrissi, H.; Amin-Ahmadi, B.; Prima, F.; Schryvers, D.; Jacques, P.J.
Title On the nucleation mechanism of {112} < 111 > mechanical twins in as-quenched beta metastable Ti-12 wt.% Mo alloy Type A1 Journal article
Year 2019 Publication Materialia Abbreviated Journal
Volume 7 Issue Pages Unsp 100418
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Recently developed beta-metastable Ti grades take advantage of the simultaneous activation of TRIP and TWIP effects for enhancing their work hardening rate. However, the role of each plasticity mechanism on the macroscopic mechanical response is still unclear. In this work, the nucleation mechanism of the first activated plasticity mechanism, namely {112} < 111 > twinning, was investigated. Firstly, post-mortem TEM analysis showed that twins nucleate on pre-existing microstructural defects such as thermal jogs with the zonal dislocation mechanism. The precipitation of the omega phase on twin boundaries has been observed, as well as the emission of numerous dislocations from super-jogs present in these twin boundaries. It is also shown that {112} < 111 > twins act as effective dislocation sources for the subsequent plasticity mechanisms such as beta -> alpha '' martensitic transformation and {332} < 111 > twinning. Secondly, in situ TEM tensile testing of the investigated Ti grade highlighted the primary role of the initial defect configuration present in the microstructure. It is shown that twins cannot nucleate without the presence of specific defects allowing the triggering of the dislocation decomposition needed for the twinning mechanism highlighted in investigated bulk samples.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000537131000052 Publication Date 2019-07-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2589-1529 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:170326 Serial (down) 6875
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Author Neelisetty, K.K.; Kumar C.N., S.; Kashiwar, A.; Scherer, T.; Chakravadhanula, V.S.K.; Kuebel, C.
Title Novel thin film lift-off process for in situ TEM tensile characterization Type A1 Journal article
Year 2021 Publication Microscopy And Microanalysis Abbreviated Journal Microsc Microanal
Volume 27 Issue S1 Pages 216-217
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2021-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276 ISBN Additional Links UA library record
Impact Factor 1.891 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 1.891
Call Number UA @ admin @ c:irua:183617 Serial (down) 6873
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Author Jannis, D.
Title Novel detection schemes for transmission electron microscopy Type Doctoral thesis
Year 2021 Publication Abbreviated Journal
Volume Issue Pages iv, 208 p.
Keywords Doctoral thesis; Electron microscopy for materials research (EMAT)
Abstract Electron microscopy is an excellent tool which provides resolution down to the atomic scale with up to pm precision in locating atoms. The characterization of materials in these length scales is of utmost importance to answer questions in biology, chemistry and material science. The successful implementation of aberration-corrected microscopes made atomic resolution imaging relatively easy, this could give the impression that the development of novel electron microscopy techniques would stagnate and only the application of these instruments as giant magnifying tools would continue. This is of course not true and a multitude of problems still exist in electron microscopy. Two of such issues are discussed below. One of the biggest problems in electron microscopy is the presence of beam damage which occurs due the fact that the highly energetic incoming electrons have sufficient kinetic energy to change the structure of the material. The amount of damage induced depends on the dose, hence minimizing this dose during an experiment is beneficial. This minimizing of the total dose comes at the expense of more noise due to the counting nature of the electrons. For this reason, the implementation of four dimensional scanning transmission electron microscopy (4D STEM) experiments has reduced the total dose needed per acquisition. However, the current cameras used to measure the diffraction patterns are still two orders of magnitude slower than to the conventional STEM methods. Improving the acquisition speed would make the 4D STEM technique more feasible and is of utmost importance for the beam sensitive materials since less dose is used during the acquisition. In TEM there is not only the possibility to perform imaging experiments but also spectroscopic measurements. There are two frequently used methods: electron energy-loss spectroscopy (EELS) and energy dispersive x-ray spectroscopy (EDX). EELS measures the energy-loss spectrum of the incoming electron which gives information on the available excitations in the material providing elemental sensitivity. In EDX, the characteristic x-rays, arising from the decay of an atom which is initially excited due to the incoming electrons, are detected providing similar elemental analysis. Both methods are able to provide comparable elemental information where in certain circumstances one outperforms the other. However, both methods have a detection limit of approximately 100-1000 ppm which is not sufficient for some materials. In this thesis, two novel techniques which can make significant progress for the two problems discussed above.
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Publisher Place of Publication Editor
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 UA @ admin @ c:irua:182404 Serial (down) 6872
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Author Gorji, S.; Kashiwar, A.; Mantha, L.S.; Kruk, R.; Witte, R.; Marek, P.; Hahn, H.; Kübel, C.; Scherer, T.
Title Nanowire facilitated transfer of sensitive TEM samples in a FIB Type A1 Journal article
Year 2020 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 219 Issue Pages 113075
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We introduce a facile approach to transfer thin films and other mechanically sensitive TEM samples inside a FIB with minimal introduction of stress and bending. The method is making use of a pre-synthetized flexible freestanding Ag nanowire attached to the tip of a typical tungsten micromanipulator inside the FIB. The main advantages of this approach are the significantly reduced stress-induced bending during transfer and attachment of the TEM sample, the very short time required to attach and cut the nanowire, the operation at very low dose and ion current, and only using the e-beam for Pt deposition during the transfer of sensitive TEM samples. This results in a reduced sample preparation time and reduced exposure to the ion beam or e-beam for Pt deposition during the sample preparation and thus also reduced contamination and beam damage. The method was applied to a number of thin films and different TEM samples in order to illustrate the advantageous benefits of the concept. In particular, the technique has been successfully tested for the transfer of a thin film onto a MEMS heating chip for in situ TEM experiments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-07-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991 ISBN Additional Links UA library record
Impact Factor 2.2 Times cited Open Access
Notes Approved Most recent IF: 2.2; 2020 IF: 2.843
Call Number UA @ admin @ c:irua:183618 Serial (down) 6871
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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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Corporate Author Thesis
Publisher Place of Publication Editor
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 UA @ admin @ c:irua:179514 Serial (down) 6870
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Author Sanchez-Iglesias, A.; Jenkinson, K.; Bals, S.; Liz-Marzan, L.M.
Title Kinetic regulation of the synthesis of pentatwinned gold nanorods below room temperature Type A1 Journal article
Year 2021 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume 125 Issue 43 Pages 23937-23944
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The synthesis of gold nanorods requires the presence of symmetry-breaking and shape-directing additives, among which bromide ions and quaternary ammonium surfactants have been reported as essential. As a result, hexadecyltrimethylammonium bromide (CTAB) has been selected as the most efficient surfactant to direct anisotropic growth. One of the difficulties arising from this selection is the low solubility of CTAB in water at room temperature, and therefore the seeded growth of gold nanorods is usually performed at 25 degrees C or above, which has restricted so far the analysis of kinetic effects derived from lower temperatures. We report a systematic study of the synthesis of gold nanorods from pentatwinned seeds using hexadecyltrimethylammonium chloride (CTAC) as the principal surfactant and a low concentration of bromide as shape-directing agent. Under these conditions, the synthesis can be performed at temperatures as low as 8 degrees C, and the corresponding kinetic effects can be studied, resulting in temperature-controlled aspect ratio tunability.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000716453300038 Publication Date 2021-10-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 6 Open Access OpenAccess
Notes realnano; sygmaSB; This work was supported by the National Science Foundation (NSF) under award NSF CHE-1808502 (P.C. and I.J.). This work made use of the EPIC facility of Northwestern University's NUANCE Center, which has received support from the SHyNE Resource (NSF ECCS-2025633), the IIN, and Northwestern's MRSEC program (NSF DMR-1720139). D.A E. and S.B. acknowledge funding from the European Research Council under the European Union's Horizon 2020 research and innovation program (ERC Consolidator Grants No. 815128 REALNANO and Grant Agreement No. 731019 EUSMI). Approved Most recent IF: 4.536
Call Number UA @ admin @ c:irua:184104 Serial (down) 6868
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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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Corporate Author Thesis
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 UA @ admin @ c:irua:180504 Serial (down) 6867
Permanent link to this record
 
 
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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Corporate Author Thesis
Publisher Place of Publication Editor
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 UA @ admin @ c:irua:180654 Serial (down) 6866
Permanent link to this record
 
 
Author Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J.
Title Electron Bessel beam diffraction patterns, line scan of Si/SiGe multilayer Type Dataset
Year 2019 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT)
Abstract
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Publisher Place of Publication Editor
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 no
Call Number UA @ admin @ c:irua:169114 Serial (down) 6865
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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.
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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 UA @ admin @ c:irua:181656 Serial (down) 6864
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Author Haug, C.; Ruebeling, F.; Kashiwar, A.; Gumbsch, P.; Kübel, C.; Greiner, C.
Title Early deformation mechanisms in the shear affected region underneath a copper sliding contact Type A1 Journal article
Year 2020 Publication Nature Communications Abbreviated Journal Nat Commun
Volume 11 Issue 1 Pages 839-8
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Dislocation mediated plastic deformation decisively influences the friction coefficient and the microstructural changes at many metal sliding interfaces during tribological loading. This work explores the initiation of a tribologically induced microstructure in the vicinity of a copper twin boundary. Two distinct horizontal dislocation traces lines (DTL) are observed in their interaction with the twin boundary beneath the sliding interface. DTL formation seems unaffected by the presence of the twin boundary but the twin boundary acts as an indicator of the occurring deformation mechanisms. Three concurrent elementary processes can be identified: simple shear of the subsurface area in sliding direction, localized shear at the primary DTL and crystal rotation in the layers above and between the DTLs around axes parallel to the transverse direction. Crystal orientation analysis demonstrates a strong compatibility of these proposed processes. Quantitatively separating these different deformation mechanisms is crucial for future predictive modeling of tribological contacts.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-02-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record
Impact Factor 16.6 Times cited Open Access
Notes Approved Most recent IF: 16.6; 2020 IF: 12.124
Call Number UA @ admin @ c:irua:183619 Serial (down) 6863
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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 UA @ admin @ c:irua:180450 Serial (down) 6861
Permanent link to this record
 
 
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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
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 UA @ admin @ c:irua:181137 Serial (down) 6860
Permanent link to this record
 
 
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 UA @ admin @ c:irua:181617 Serial (down) 6859
Permanent link to this record
 
 
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
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-4248 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:180862 Serial (down) 6858
Permanent link to this record
 
 
Author Villarreal, R.; Lin, P.-C.; Faraji, F.; Hassani, N.; Bana, H.; Zarkua, Z.; Nair, M.N.; Tsai, H.-C.; Auge, M.; Junge, F.; Hofsaess, H.C.; De Gendt, S.; De Feyter, S.; Brems, S.; Ahlgren, E.H.; Neyts, E.C.; Covaci, L.; Peeters, F.M.; Neek-Amal, M.; Pereira, L.M.C.
Title Breakdown of universal scaling for nanometer-sized bubbles in graphene Type A1 Journal article
Year 2021 Publication Nano Letters Abbreviated Journal Nano Lett
Volume 21 Issue 19 Pages 8103-8110
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We report the formation of nanobubbles on graphene with a radius of the order of 1 nm, using ultralow energy implantation of noble gas ions (He, Ne, Ar) into graphene grown on a Pt(111) surface. We show that the universal scaling of the aspect ratio, which has previously been established for larger bubbles, breaks down when the bubble radius approaches 1 nm, resulting in much larger aspect ratios. Moreover, we observe that the bubble stability and aspect ratio depend on the substrate onto which the graphene is grown (bubbles are stable for Pt but not for Cu) and trapped element. We interpret these dependencies in terms of the atomic compressibility of the noble gas as well as of the adhesion energies between graphene, the substrate, and trapped atoms.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000709549100026 Publication Date 2021-09-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 12 Open Access OpenAccess
Notes Approved Most recent IF: 12.712
Call Number UA @ admin @ c:irua:184137 Serial (down) 6857
Permanent link to this record
 
 
Author Mahadi, A.H.; Ye, L.; Fairclough, S.M.; Qu, J.; Wu, S.; Chen, W.; Papaioannou, E.; Ray, B.; Pennycook, T.J.; Haigh, S.J.; Young, N.P.; Tedsree, K.; Metcalfe, I.S.; Tsang, S.C.E.
Title Beyond surface redox and oxygen mobility at pd-polar ceria (100) interface : underlying principle for strong metal-support interactions in green catalysis Type A1 Journal article
Year 2020 Publication Applied Catalysis B-Environmental Abbreviated Journal Appl Catal B-Environ
Volume 270 Issue Pages 118843
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract When ceria is used as a support for many redox catalysis involved in green catalysis, it is well-known that the overlying noble metal can gain access to a significant quantity of oxygen atoms with high mobility and fast reduction and oxidation properties under mild conditions. However, it is as yet unclear what the underlying principle and the nature of the ceria surface involved are. By using two tailored morphologies of ceria nanocrystals, namely cubes and rods, it is demonstrated from Scanning Transmission Electron Microscopy with Electron Energy Loss Spectroscopy (STEM-EELS) mapping and Pulse Isotopic Exchange (PIE) that ceria nano-cubes terminated with a polar surface (100) can give access to more than the top most layer of surface oxygen atoms. Also, they give higher oxygen mobility than ceria nanorods with a non-polar facet of (110). A new insight for the possible additional role of polar ceria surface plays in the oxygen mobility is obtained from Density Functional Theory (DFT) calculations which suggest that the (100) surface sites that has more than half-filled O on same plane can drive oxygen atoms to oxidise adsorbate(s) on Pd due to the strong electrostatic repulsion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000526110500007 Publication Date 2020-03-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0926-3373 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 22.1 Times cited Open Access
Notes Approved Most recent IF: 22.1; 2020 IF: 9.446
Call Number UA @ admin @ c:irua:183959 Serial (down) 6856
Permanent link to this record
 
 
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.
Address
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 UA @ admin @ c:irua:179564 Serial (down) 6855
Permanent link to this record
 
 
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.
Address
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 UA @ admin @ c:irua:179679 Serial (down) 6854
Permanent link to this record
 
 
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 UA @ admin @ c:irua:181658 Serial (down) 6853
Permanent link to this record
 
 
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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
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 UA @ admin @ c:irua:180973 Serial (down) 6852
Permanent link to this record
 
 
Author Zhang, Z.; Bourgeois, L.; Zhang, Y.; Rosalie, J.M.; Medhekar, N.
Title Advanced imaging and simulations of precipitate interfaces in aluminium alloys and their role in phase transformations Type P1 Proceeding
Year 2020 Publication MATEC web of conferences T2 – 17th International Conference on Aluminium Alloys (ICAA), October 26-29, 2020 Abbreviated Journal
Volume Issue Pages 09003
Keywords P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Precipitation is accompanied by the formation and migration of heterophase interfaces. Using the combined approach of advanced imaging and atomistic simulations, we studied the precipitate-matrix interfaces in various aluminium alloy systems, aiming to resolve their detailed atomic structures and illuminate their role in phase transformations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000652552200053 Publication Date 2020-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume 326 Series Issue Edition
ISSN 2261-236x; 2274-7214 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:179147 Serial (down) 6851
Permanent link to this record
 
 
Author Madsen, J.; Pennycook, T.J.; Susi, T.
Title ab initio description of bonding for transmission electron microscopy Type A1 Journal article
Year 2021 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 231 Issue Pages
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The simulation of transmission electron microscopy (TEM) images or diffraction patterns is often required to interpret their contrast and extract specimen features. This is especially true for high-resolution phase-contrast imaging of materials, but electron scattering simulations based on atomistic models are widely used in materials science and structural biology. Since electron scattering is dominated by the nuclear cores, the scattering potential is typically described by the widely applied independent atom model. This approximation is fast and fairly accurate, especially for scanning TEM (STEM) annular dark-field contrast, but it completely neglects valence bonding and its effect on the transmitting electrons. However, an emerging trend in electron microscopy is to use new instrumentation and methods to extract the maximum amount of information from each electron. This is evident in the increasing popularity of techniques such as 4D-STEM combined with ptychography in materials science, and cryogenic microcrystal electron diffraction in structural biology, where subtle differences in the scattering potential may be both measurable and contain additional insights. Thus, there is increasing interest in electron scattering simulations based on electrostatic potentials obtained from first principles, mainly via density functional theory, which was previously mainly required for holography. In this Review, we discuss the motivation and basis for these developments, survey the pioneering work that has been published thus far, and give our outlook for the future. We argue that a physically better justified ab initio description of the scattering potential is both useful and viable for an increasing number of systems, and we expect such simulations to steadily gain in popularity and importance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000744190300006 Publication Date 2021-03-18
Series Editor Series Title Abbreviated Series Title
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 Open Access OpenAccess
Notes Approved Most recent IF: 2.843
Call Number UA @ admin @ c:irua:183955 Serial (down) 6850
Permanent link to this record
 
 
Author Shi, R.; Choudhuri, D.; Kashiwar, A.; Dasari, S.; Wang, Y.; Banerjee, R.; Banerjee, D.
Title α phase growth and branching in titanium alloys Type A1 Journal article
Year 2021 Publication Philosophical magazine Abbreviated Journal Philos Mag
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The morphology and spatial distribution of alpha (α) precipitates have been mapped as a function of Mo content in Ti-Mo binary alloys employing a combinatorial approach. Heat-treatments were carried out on compositionally graded Ti-xMo samples processed using a rapid throughput laser engineered net shape (LENS) process. The composition space spans 1.5 at% to 6 at% Mo with ageing at 750°C, 650°C and 600°C following a β solution treatment. Three distinct regimes of α morphology and distribution were observed. These are colony-dominated microstructures originating from grain boundary α allotriomorphs, bundles of intragranular α laths, and homogeneously distributed individual fine-scale α laths. Branching of the α precipitates was observed in all these domains in a manner reminiscent of solid-state dendritic growth. The phenomenon is particularly apparent at low volume fractions of α. Similar features are present in a wide variety of alloy compositions. 3-dimensional features of such branched structures have been analysed. Simulation of the branching process by phase field methods incorporating anisotropy in the α/β interface energy and elasticity suggests that it can be initiated at growth ledges present at broad faces of the α laths, driven by the enhancement of the diffusion flux at these steps. The dependence of branching on various parameters such as supersaturation and diffusivity, and microstructural features like ledge height and distribution and the presence of adjacent α variants has been evaluated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000722082700001 Publication Date 2021-11-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1478-6435 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.505 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 1.505
Call Number UA @ admin @ c:irua:183616 Serial (down) 6849
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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 UA @ admin @ c:irua:181261 Serial (down) 6848
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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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
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 UA @ admin @ c:irua:182261 Serial (down) 6847
Permanent link to this record
 
 
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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
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 UA @ admin @ c:irua:180553 Serial (down) 6846
Permanent link to this record