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Author |
Verdierre, G.; Gauquelin, N.; Jannis, D.; Birkhölzer, Y.A.; Mallik, S.; Verbeeck, J.; Bibes, M.; Koster, G. |
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Title |
Epitaxial growth of the candidate ferroelectric Rashba material SrBiO3by pulsed laser deposition |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
APL materials |
Abbreviated Journal |
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Volume |
11 |
Issue |
3 |
Pages |
031109 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Among oxides, bismuthates have been gaining much interest due to their unique features. In addition to their superconducting properties, they show potential for applications as topological insulators and as possible spin-to-charge converters. After being first investigated in their bulk form in the 1980s, bismuthates have been successfully grown as thin films. However, most efforts have focused on BaBiO<sub>3</sub>, with SrBiO<sub>3</sub>receiving only little attention. Here, we report the growth of epitaxial films of SrBiO<sub>3</sub>on both TiO<sub>2</sub>-terminated SrTiO<sub>3</sub>and NdO-terminated NdScO<sub>3</sub>substrates by pulsed laser deposition. SrBiO<sub>3</sub>has a pseudocubic lattice constant of ∼4.25 Å and grows relaxed on NdScO<sub>3</sub>. Counter-intuitively, it grows with a slight tensile strain on SrTiO<sub>3</sub>despite a large lattice mismatch, which should induce compressive strain. High-resolution transmission electron microscopy reveals that this occurs as a consequence of structural domain matching, with blocks of 10 SrBiO<sub>3</sub>unit planes matching blocks of 11 SrTiO<sub>3</sub>unit planes. This work provides a framework for the synthesis of high quality perovskite bismuthates films and for the understanding of their interface interactions with homostructural substrates. |
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Wos |
000953363800004 |
Publication Date |
2023-03-01 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2166-532X |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
6.1 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
This work received support from the ERC Advanced grant (Grant No. 833973) “FRESCO” and funding from the European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No. 823717—ESTEEM3, Van Gogh travel grant, Nuffic, The Netherlands (CF No. 42582SB).; esteem3reported; esteem3TA |
Approved |
Most recent IF: 6.1; 2023 IF: 4.335 |
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Call Number  |
EMAT @ emat @c:irua:196135 |
Serial |
7377 |
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| Permanent link to this record |
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Author |
Kavak, S.; Kadu, A.A.; Claes, N.; Sánchez-Iglesias, A.; Liz-Marzán, L.M.; Batenburg, K.J.; Bals, S. |
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Title |
Quantitative 3D Investigation of Nanoparticle Assemblies by Volumetric Segmentation of Electron Tomography Data Sets |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
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Volume |
127 |
Issue |
20 |
Pages |
9725-9734 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Morphological characterization of nanoparticle assemblies and hybrid nanomaterials is critical in determining their structure-property relationships as well as in the development of structures with desired properties. Electron tomography has become a widely utilized technique for the three-dimensional characterization of nanoparticle assemblies. However, the extraction of quantitative morphological parameters from the reconstructed volume can be a complex and labor-intensive task. In this study, we aim to overcome this challenge by automating the volumetric segmentation process applied to three-dimensional reconstructions of nanoparticle assemblies. The key to enabling automated characterization is to assess the performance of different volumetric segmentation methods in accurately extracting predefined quantitative descriptors for morphological characterization. In our methodology, we compare the quantitative descriptors obtained through manual segmentation with those obtained through automated segmentation methods, to evaluate their accuracy and effectiveness. To show generality, our study focuses on the characterization of assemblies of CdSe/CdS quantum dots, gold nanospheres and CdSe/CdS encapsulated in polymeric micelles, and silica-coated gold nanorods decorated with both CdSe/CdS or PbS quantum dots. We use two unsupervised segmentation algorithms: the watershed transform and the spherical Hough transform. Our results demonstrate that the choice of automated segmentation method is crucial for accurately extracting the predefined quantitative descriptors. Specifically, the spherical Hough transform exhibits superior performance in accurately extracting quantitative descriptors, such as particle size and interparticle distance, thereby allowing for an objective, efficient, and reliable volumetric segmentation of complex nanoparticle assemblies. |
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Wos |
000991752700001 |
Publication Date |
2023-05-25 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
Fonds Wetenschappelijk Onderzoek, 1181122N ; Horizon 2020 Framework Programme, 861950 ; H2020 European Research Council, 815128 ; |
Approved |
Most recent IF: 3.7; 2023 IF: 4.536 |
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Call Number |
EMAT @ emat @c:irua:196971 |
Serial |
8793 |
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| Permanent link to this record |
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Author |
Samal, D.; Gauquelin, N.; Takamura, Y.; Lobato, I.; Arenholz, E.; Van Aert, S.; Huijben, M.; Zhong, Z.; Verbeeck, J.; Van Tendeloo, G.; Koster, G. |
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Title |
Unusual structural rearrangement and superconductivity in infinite layer cuprate superlattices |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
7 |
Issue |
5 |
Pages |
054803 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
001041792100007 |
Publication Date |
2023-05-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Air Force Office of Scientific Research; European Office of Aerospace Research and Development, FA8655-10-1-3077 ; Office of Science, DE-AC02-05CH11231 ; National Science Foundation, DMR-1745450 ; Seventh Framework Programme, 278510 ; Bijzonder Onderzoeksfonds UGent; |
Approved |
Most recent IF: 3.4; 2023 IF: NA |
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Call Number |
EMAT @ emat @c:irua:196973 |
Serial |
8790 |
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| Permanent link to this record |
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Author |
Vlasov, E.; Skorikov, A.; Sánchez-Iglesias, A.; Liz-Marzán, L.M.; Verbeeck, J.; Bals, S. |
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Title |
Secondary electron induced current in scanning transmission electron microscopy: an alternative way to visualize the morphology of nanoparticles |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
ACS materials letters |
Abbreviated Journal |
ACS Materials Lett. |
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Volume |
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Issue |
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Pages |
1916-1921 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Electron tomography (ET) is a powerful tool to determine the three-dimensional (3D) structure of nanomaterials in a transmission electron microscope. However, the acquisition of a conventional tilt series for ET is a time-consuming process and can therefore not provide 3D structural information in a time-efficient manner. Here, we propose surface-sensitive secondary electron (SE) imaging as an alternative to ET for the investigation of the morphology of nanomaterials. We use the SE electron beam induced current (SEEBIC) technique that maps the electrical current arising from holes generated by the emission of SEs from the sample. SEEBIC imaging can provide valuable information on the sample morphology with high spatial resolution and significantly shorter throughput times compared with ET. In addition, we discuss the contrast formation mechanisms that aid in the interpretation of SEEBIC data. |
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Wos |
001006191600001 |
Publication Date |
2023-06-12 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2639-4979 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
The funding for this project was provided by European Research Council (ERC Consolidator Grant 815128, REALNANO). J.V. acknowledges the eBEAM project, which is supported by the European Union’s Horizon 2020 research and innovation program under grant agreement no. 101017720 (FET-Proactive EBEAM). L.M.L.-M. acknowledges funding from MCIN/AEI/10.13039/501100011033 (grant # PID2020-117779RB-I00). |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @c:irua:197004 |
Serial |
8795 |
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Author |
Saniz, R.; Baldinozzi, G.; Arts, I.; Lamoen, D.; Leinders, G.; Verwerft, M. |
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Title |
Charge order, frustration relief, and spin-orbit coupling in U3O8 |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
7 |
Issue |
5 |
Pages |
054410 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Research efforts on the description of the low-temperature magnetic order and electronic properties of U3O8 have been inconclusive so far. Reinterpreting neutron scattering results, we use group representation theory to show that the ground state presents collinear out-of-plane magnetic moments, with antiferromagnetic coupling both in-layer and between layers. Charge order relieves the initial geometric frustration, generating a slightly distorted honeycomb sublattice with Néel-type order. The precise knowledge of the characteristics of this magnetic ground state is then used to explain the fine features of the band gap. In this system, spin-orbit coupling (SOC) is of critical importance, as it strongly affects the electronic structure, narrowing the gap by ∼38%, compared to calculations neglecting SOC. The predicted electronic structure actually explains the salient features of recent optical absorption measurements, further demonstrating the excellent agreement between the calculated ground state properties and experiment. |
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Wos |
001041429800007 |
Publication Date |
2023-05-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Financial support for this research was partly provided by the Energy Transition Fund of the Belgian FPS Economy (Project SF-CORMOD Spent Fuel CORrosion MODeling).Fonds Wetenschappelijk Onderzoek; Vlaams Supercomputer Centrum; Universiteit Antwerpen; Vlaamse regering; |
Approved |
Most recent IF: 3.4; 2023 IF: NA |
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Call Number |
EMAT @ emat @c:irua:197043 |
Serial |
8796 |
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Author |
Carrasco, S.; Orcajo, G.; Martínez, F.; Imaz, I.; Kavak, S.; Arenas-Esteban, D.; Maspoch, D.; Bals, S.; Calleja, G.; Horcajada, P. |
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Title |
Hf/porphyrin-based metal-organic framework PCN-224 for CO2 cycloaddition with epoxides |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Materials Today Advances |
Abbreviated Journal |
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Volume |
19 |
Issue |
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Pages |
100390 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Herein, we describe for the first time the synthesis of the highly porous Hf-tetracarboxylate porphyrin-based metal-organic framework (MOF) (Hf)PCN-224(M) (M = H2, Co2+). (Hf)PCN-224(H2) was easily and efficiently prepared following a simple microwave-assisted procedure with good yields (56–67%; space-time yields: 1100–1270 kg m−3·day−1), high crystallinity and phase purity by using trifluoromethanesulfonic acid and benzoic acid as modulators in less than 30 min. By simply introducing a preliminary step (10 min), 5,10,15,20-(tetra-4-carboxyphenyl)porphyrin linker (TCPP) was quantitatively metalated with Co2+ without additional purification and/or time consuming protection/deprotection steps to further obtain (Hf)PCN-224(Co). (Hf)PCN-224(Co) was then tested as catalyst in CO2 cycloaddition reaction with different epoxides to yield cyclic carbonates, showing the best catalytic performance described to date compared to other PCNs, under mild conditions (1 bar CO2, room temperature, 18–24 h). Twelve epoxides were tested, obtaining from moderate to excellent conversions (35–96%). Moreover, this reaction was gram scaled-up (x50) without significant loss of yield to cyclic carbonates. (Hf)PCN-224(Co) maintained its integrity and crystallinity even after 8 consecutive runs, and poisoning was efficiently reverted by a simple thermal treatment (175 °C, 6 h), fully recovering the initial catalytic activity. |
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Wos |
001025764000001 |
Publication Date |
2023-06-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2590-0498 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
S.C. acknowledges the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie (MSCA-COFUND) grant agreement No 754382 (GOT Energy Talent). S.C. and P.H. acknowledge “Comunidad de Madrid” and European Regional Development Fund-FEDER 2014-2020-OE REACT-UE 1 for their financial support to VIRMOF-CM project associated to R&D projects in response to COVID-19. The authors acknowledge H2020-MSCA-ITN-2019 HeatNMof (ref. 860942), the M-ERA-NET C-MOF-cell (grant PCI2020-111998 funded by MCIN/AEI /10.13039/501100011033 and European Union NextGenerationEU/PRTR) project, and Retos Investigación MOFSEIDON (grant PID2019-104228RB-I00 funded by MCIN/AEI/10.13039/501100011033) project. This work has been also supported by the Regional Government of Madrid (Project ACES2030-CM, S2018/EMT-4319) and the Universidad Rey Juan Carlos IMPULSO Project (grant MATER M − 3000). S.K acknowledges the Flemish Fund for Scientific Research (FWO Vlaanderen) through a PhD research grant (1181122 N). |
Approved |
Most recent IF: 10; 2023 IF: NA |
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Call Number |
EMAT @ emat @c:irua:197198 |
Serial |
8800 |
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Author |
Sa, J.; Hu, N.; Heyvaert, W.; Van Gordon, K.; Li, H.; Wang, L.; Bals, S.; Liz-Marzán, L.M.; Ni, W. |
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Title |
Spontaneous Chirality Evolved at the Au–Ag Interface in Plasmonic Nanorods |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem. Mater. |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Chiral ligands are considered a required ingredient during the synthesis of dissymmetric plasmonic metal nanocrystals. The mechanism behind the generation of chiral structures involves the formation of high Miller index chiral facets, induced by the adsorption of such chiral ligands. We found however that, chirality can also evolve spontaneously, without the involvement of any chiral ligands, during the co-deposition of Au and Ag on Au nanorods. When using a specific Au/Ag ratio, phase segregation of the two metals leads to an interface within the obtained AuAg shell, which can be exposed by removing the Ag component via oxidative etching. Although a close-to-racemic mixture of chiral Au nanorods with right and left handedness is found in solution, electron tomography analysis evidences left- and righthanded helicities, both at the Au-Ag interface and at the exposed surface of Au NRs after Ag etching. The helicity profile of the NRs indicates dominating inclination angles in a range from 30° to 60°. Single-particle optical characterization also reveals random handedness in the plasmonic response of individual nanorods. We hypothesize that, the origin of chirality is related with symmetry breaking during the co-deposition of Au and Ag, through an initial perturbation in a small region on the Au-Ag interface that eventually leads to chiral segregation throughout the nanocrystal. |
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Wos |
001052093300001 |
Publication Date |
2023-08-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
8.6 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
The authors acknowledge the financial support from the National Natural Science Foundation of China (grant 22074102). LMLM acknowledges funding from 26 MCIN/AEI/10.13039/501100011033 and “ESF Investing in your future” (Grant PID2020- 117779RB-I00). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3.; Ministerio de Ciencia e Innovaci?n, PID2020-117779RB-I00 ; H2020 Research Infrastructures, 823717 ; European Social Fund, PID2020-117779RB-I00 ; National Natural Science Foundation of China, 22074102 ; |
Approved |
Most recent IF: 8.6; 2023 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:198151 |
Serial |
8810 |
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Author |
Paulus, A.; Hendrickx, M.; Mayda, S.; Batuk, M.; Reekmans, G.; von Holst, M.; Elen, K.; Abakumov, A.M.; Adriaensens, P.; Lamoen, D.; Partoens, B.; Hadermann, J.; Van Bael, M.K.; Hardy, A. |
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Title |
Understanding the Activation of Anionic Redox Chemistry in Ti4+-Substituted Li2MnO3as a Cathode Material for Li-Ion Batteries |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
ACS Appl. Energy Mater. |
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Volume |
6 |
Issue |
13 |
Pages |
6956-6971 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Layered Li-rich oxides, demonstrating both cationic and anionic redox chemistry being used as positive electrodes for Li-ion batteries,have raised interest due to their high specific discharge capacities exceeding 250 mAh/g. However, irreversible structural transformations triggered by anionic redox chemistry result in pronounced voltagefade (i.e., lowering the specific energy by a gradual decay of discharge potential) upon extended galvanostatic cycling. Activating or suppressing oxygen anionic redox through structural stabilization induced by redox-inactivecation substitution is a well-known strategy. However, less emphasishas been put on the correlation between substitution degree and theactivation/suppression of the anionic redox. In this work, Ti4+-substituted Li2MnO3 was synthesizedvia a facile solution-gel method. Ti4+ is selected as adopant as it contains no partially filled d-orbitals. Our study revealedthat the layered “honeycomb-ordered” C2/m structure is preserved when increasing the Ticontent to x = 0.2 in the Li2Mn1-x Ti (x) O-3 solidsolution, as shown by electron diffraction and aberration-correctedscanning transmission electron microscopy. Galvanostatic cycling hintsat a delayed oxygen release, due to an improved reversibility of theanionic redox, during the first 10 charge-discharge cyclesfor the x = 0.2 composition compared to the parentmaterial (x = 0), followed by pronounced oxygen redoxactivity afterward. The latter originates from a low activation energybarrier toward O-O dimer formation and Mn migration in Li2Mn0.8Ti0.2O3, as deducedfrom first-principles molecular dynamics (MD) simulations for the“charged” state. Upon lowering the Ti substitution to x = 0.05, the structural stability was drastically improvedbased on our MD analysis, stressing the importance of carefully optimizingthe substitution degree to achieve the best electrochemical performance. |
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Wos |
001018266700001 |
Publication Date |
2023-07-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2574-0962 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.4 |
Times cited |
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Open Access |
Not_Open_Access: Available from 24.12.2023 |
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Notes |
Universiteit Hasselt, AUHL/15/2 – GOH3816N ; Russian Science Foundation, 20-43-01012 ; Fonds Wetenschappelijk Onderzoek, AUHL/15/2 – GOH3816N G040116N ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 6.4; 2023 IF: NA |
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Call Number |
EMAT @ emat @c:irua:198160 |
Serial |
8809 |
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Author |
Bhatia, H.; Keshavarz, M.; Martin, C.; Van Gaal, L.; Zhang, Y.; de Coen, B.; Schrenker, N.J.; Valli, D.; Ottesen, M.; Bremholm, M.; Van de Vondel, J.; Bals, S.; Hofkens, J.; Debroye, E. |
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Title |
Achieving High Moisture Tolerance in Pseudohalide Perovskite Nanocrystals for Light-Emitting Diode Application |
Type |
A1 Journal Article |
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Year |
2023 |
Publication |
ACS Applied Optical Materials |
Abbreviated Journal |
ACS Appl. Opt. Mater. |
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Volume |
1 |
Issue |
6 |
Pages |
1184-1191 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
The addition of potassium thiocyanate (KSCN) to the FAPbBr3 structure and subsequent post-treatment of nanocrystals (NCs) lead to high quantum confinement, resulting in a photoluminescent quantum yield (PLQY) approaching unity and microsecond decay times. This synergistic approach demonstrated exceptional stability under humid conditions, retaining 70% of the PLQY for over a month, while the untreated NCs degrade within 24 h. Additionally, the devices incorporating the post-treated NCs displayed 1.5% external quantum efficiency (EQE), a 5-fold improvement over untreated devices. These results provide promising opportunities for the use of perovskites in moisture-stable optoelectronics. |
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Wos |
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Publication Date |
2023-06-23 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2771-9855 |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
OpenAccess |
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Notes |
Hercules Foundation, HER/11/14 ; European Commission; Ministerio de Ciencia e Innovaci?n, PID2021-128761OA-C22 ; European Regional Development Fund; Vlaamse regering, CASAS2 Meth/15/04 ; Fonds Wetenschappelijk Onderzoek, 1238622N 1514220N 1S45223N G.0B39.15 G.0B49.15 G098319N S002019N ZW15_09-GOH6316 ; Onderzoeksraad, KU Leuven, C14/19/079 db/21/006/bm iBOF-21-085 STG/21/010 ; Junta de Comunidades de Castilla-La Mancha, SBPLY/21/180501/000127 ; H2020 European Research Council, 642196 815128 ; |
Approved |
Most recent IF: NA |
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| |
Call Number |
EMAT @ emat @c:irua:201011 |
Serial |
8975 |
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| Permanent link to this record |
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Author |
Ding, L.; Zhao, M.; Ehlers, F.J.H.; Jia, Z.; Zhang, Z.; Weng, Y.; Schryvers, D.; Liu, Q.; Idrissi, H. |
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Title |
“Branched” structural transformation of the L12-Al3Zr phase manipulated by Cu substitution/segregation in the Al-Cu-Zr alloy system |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Journal of materials science & technology |
Abbreviated Journal |
Journal of Materials Science & Technology |
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| |
Volume |
185 |
Issue |
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Pages |
186-206 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The effect of Cu on the evolution of the Al3Zr phase in an Al-Cu-Zr cast alloy during solution treatment at 500 °C has been thoroughly studied by combining atomic resolution high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy and first-principles cal- culations. The heat treatment initially produces a pure L12-Al3Zr microstructure, allowing for about 13 % Cu to be incorporated in the dispersoid. Cu incorporation increases the energy barrier for anti-phase boundary (APB) activation, thus stabilizing the L12 structure. Additional heating leads to a Cu-induced “branched”path for the L12 structural transformation, with the latter process accelerated once the first APB has been created. Cu atoms may either (i) be repelled by the APBs, promoting the transformation to a Cu-poor D023 phase, or (ii) they may segregate at one Al-Zr layer adjacent to the APB, promoting a transformation to a new thermodynamically favored phase, Al4CuZr, formed when these segregation layers are periodically arranged. Theoretical studies suggest that the branching of the L12 transformation path is linked to the speed at which an APB is created, with Cu attraction triggered by a comparatively slow process. This unexpected transformation behavior of the L12-Al3Zr phase opens a new path to understanding, and potentially regulating the Al3Zr dispersoid evolution for high temperature applications. |
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Place of Publication |
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Language |
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Wos |
001154261100001 |
Publication Date |
2023-12-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1005-0302 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
10.9 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
This work was supported by the National Key Research and Development Program (No. 2020YFA0405900), the National Natural Science Foundation of China (Grant No. 52371111 and U2141215 ), the Natural Science Foundation of Jiangsu Province (No. BE2022159 ). We are grateful to the High Performance Computing Center of Nanjing Tech University for supporting the computational resources. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR- FNRS). |
Approved |
Most recent IF: 10.9; 2024 IF: 2.764 |
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| |
Call Number |
EMAT @ emat @c:irua:202392 |
Serial |
8981 |
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| Permanent link to this record |
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Author |
Lobato, I.; Friedrich, T.; Van Aert, S. |
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Title |
Deep convolutional neural networks to restore single-shot electron microscopy images |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
N P J Computational Materials |
Abbreviated Journal |
npj Comput Mater |
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Volume |
10 |
Issue |
1 |
Pages |
10 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Advanced electron microscopy techniques, including scanning electron microscopes (SEM), scanning transmission electron microscopes (STEM), and transmission electron microscopes (TEM), have revolutionized imaging capabilities. However, achieving high-quality experimental images remains a challenge due to various distortions stemming from the instrumentation and external factors. These distortions, introduced at different stages of imaging, hinder the extraction of reliable quantitative insights. In this paper, we will discuss the main sources of distortion in TEM and S(T)EM images, develop models to describe them, and propose a method to correct these distortions using a convolutional neural network. We validate the effectiveness of our method on a range of simulated and experimental images, demonstrating its ability to significantly enhance the signal-to-noise ratio. This improvement leads to a more reliable extraction of quantitative structural information from the images. In summary, our findings offer a robust framework to enhance the quality of electron microscopy images, which in turn supports progress in structural analysis and quantification in materials science and biology. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001138183000001 |
Publication Date |
2024-01-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2057-3960 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
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Notes |
This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S.V.A.). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N, G0A7723N and EOS 40007495). S.V.A. acknowledges funding from the University of Antwerp Research Fund (BOF). The authors thank Lukas Grünewald for data acquisition and support for Fig. 7. |
Approved |
Most recent IF: NA |
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| |
Call Number |
EMAT @ emat @c:irua:202714 |
Serial |
8994 |
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Author |
Vandemeulebroucke, D.; Batuk, M.; Hajizadeh, A.; Wastiaux, M.; Roussel, P.; Hadermann, J. |
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Title |
Incommensurate Modulations and Perovskite Growth in LaxSr2–xMnO4−δAffecting Solid Oxide Fuel Cell Conductivity |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Chemistry of Materials |
Abbreviated Journal |
Chem. Mater. |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Ruddlesden-Popper La????Sr2−????MnO4−???? materials are interesting symmetric solid oxide
fuel cell electrodes due to their good redox stability, mixed ionic and electronic conducting behavior and thermal expansion that matches well with common electrolytes. In reducing environments – as at a solid oxide fuel cell anode – the x = 0.5 member, i.e. La0.5Sr1.5MnO4−????, has a much higher total conductivity than compounds with a different La/Sr ratio, although all those compositions have the same K2NiF4-type I4/mmm structure. The origin for this conductivity difference is not yet known in literature. Now, a combination of in-situ and ex-situ 3D electron diffraction, high-resolution imaging, energy-dispersive X-ray analysis and electron energy-loss spectroscopy uncovered clear differences between x=0.25 and x=0.5 in the pristine structure, as well as in the transformations upon high-temperature reduction. In La0.5Sr1.5MnO4−????, Ruddlesden-Popper n=2 layer defects and an amorphous surface layer are present, but not in La0.25Sr1.75MnO4−????. After annealing at 700°C in 5% H2/Ar, La0.25Sr1.75MnO4−???? transforms to a tetragonal 2D incommensurately modulated structure with modulation vectors ⃗????1 = 0.2848(1) · (⃗????* +⃗????*) and ⃗????2 =0.2848(1) · (⃗????* – ⃗????*), whereas La0.5Sr1.5MnO4−???? only partially transforms to an orthorhombic 1D incommensurately modulated structure,
with ⃗???? = 0.318(2) · ⃗????*. Perovskite domains grow at the crystal edge at 700°C in 5%
H2 or vacuum, due to the higher La concentration on the surface compared to the bulk, which leads to a different thermodynamic equilibrium. Since it is known that a lower degree of oxygen vacancy ordering and a higher amount of perovskite blocks enhance oxygen mobility, those differences in defect structure and structural transformation upon reduction, might all contribute to the higher conductivity of La0.5Sr1.5MnO4−???? in solid oxide fuel cell anode conditions compared to other La/Sr ratios. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
001174840900001 |
Publication Date |
2024-02-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
8.6 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
Universiteit Antwerpen, BOF TOP 38689 ; Fonds Wetenschappelijk Onderzoek, I003218N ; European Commission NanED, 956099 ; |
Approved |
Most recent IF: 8.6; 2024 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:204354 |
Serial |
8997 |
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| Permanent link to this record |
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Author |
Grünewald, L.; Chezganov, D.; De Meyer, R.; Orekhov, A.; Van Aert, S.; Bogaerts, A.; Bals, S.; Verbeeck, J. |
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Title |
In Situ Plasma Studies Using a Direct Current Microplasma in a Scanning Electron Microscope |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Advanced Materials Technologies |
Abbreviated Journal |
Adv Materials Technologies |
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Volume |
|
Issue |
|
Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Microplasmas can be used for a wide range of technological applications and to improve the understanding of fundamental physics. Scanning electron microscopy, on the other hand, provides insights into the sample morphology and chemistry of materials from the mm‐ down to the nm‐scale. Combining both would provide direct insight into plasma‐sample interactions in real‐time and at high spatial resolution. Up till now, very few attempts in this direction have been made, and significant challenges remain. This work presents a stable direct current glow discharge microplasma setup built inside a scanning electron microscope. The experimental setup is capable of real‐time in situ imaging of the sample evolution during plasma operation and it demonstrates localized sputtering and sample oxidation. Further, the experimental parameters such as varying gas mixtures, electrode polarity, and field strength are explored and experimental<italic>V</italic>–<italic>I</italic>curves under various conditions are provided. These results demonstrate the capabilities of this setup in potential investigations of plasma physics, plasma‐surface interactions, and materials science and its practical applications. The presented setup shows the potential to have several technological applications, for example, to locally modify the sample surface (e.g., local oxidation and ion implantation for nanotechnology applications) on the µm‐scale. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
001168639900001 |
Publication Date |
2024-02-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2365-709X |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
6.8 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
L.G., S.B., and J.V. acknowledge support from the iBOF-21-085 PERsist research fund. D.C., S.V.A., and J.V. acknowledge funding from a TOPBOF project of the University of Antwerp (FFB 170366). R.D.M., A.B., and J.V. acknowledge funding from the Methusalem project of the University of Antwerp (FFB 15001A, FFB 15001C). A.O. and J.V. acknowledge funding from the Research Foundation Flanders (FWO, Belgium) project SBO S000121N. |
Approved |
Most recent IF: 6.8; 2024 IF: NA |
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Call Number |
EMAT @ emat @c:irua:204363 |
Serial |
8995 |
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Author |
Ignatova, K.; Vlasov, E.; Seddon, S.D.; Gauquelin, N.; Verbeeck, J.; Wermeille, D.; Bals, S.; Hase, T.P.A.; Arnalds, U.B. |
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Title |
Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
APL Materials |
Abbreviated Journal |
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| |
Volume |
12 |
Issue |
4 |
Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
We present an investigation of the microstructure changes in V2O3 as it goes through its inherent structural phase transition. Using V2O3 films with a well-defined crystal structure deposited by reactive magnetron sputtering on r-plane Al2O3 substrates, we study the phase coexistence region and its impact on the surface roughness of the films and the magnetic properties of overlying Ni magnetic layers in V2O3/Ni hybrid magnetic heterostructures. The simultaneous presence of two phases in V2O3 during its structural phase transition was identified with high resolution x-ray diffraction and led to an increase in surface roughness observed using x-ray reflectivity. The roughness reaches its maximum at the midpoint of the transition. In V2O3/Ni hybrid heterostructures, we find a concomitant increase in the coercivity of the magnetic layer correlated with the increased roughness of the V2O3 surface. The chemical homogeneity of the V2O3 is confirmed through transmission electron microscopy analysis. High-angle annular dark field imaging and electron energy loss spectroscopy reveal an atomically flat interface between Al2O3 and V2O3, as well as a sharp interface between V2O3 and Ni. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001202661800003 |
Publication Date |
2024-04-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2166-532X |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
6.1 |
Times cited |
|
Open Access |
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| |
Notes |
This work was supported by the funding from the University of Iceland Research Fund, the Icelandic Research Fund Grant No. 207111. Instrumentation funding from the Icelandic Infrastructure Fund is acknowledged. This work was based on experiments per- formed at the BM28 (XMaS) beamline at the European Synchrotron Radiation Facility, Grenoble, France. XMaS is a National Research Facility funded by the UK EPSRC and managed by the Universi- ties of Liverpool and Warwick. This project has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717—ESTEEM3. |
Approved |
Most recent IF: 6.1; 2024 IF: 4.335 |
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Call Number |
EMAT @ emat @c:irua:205569 |
Serial |
9120 |
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| Permanent link to this record |
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Author |
Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. |
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Title |
Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion |
Type |
A1 Journal Article |
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Year |
2024 |
Publication |
Advanced Materials |
Abbreviated Journal |
Advanced Materials |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001206226700001 |
Publication Date |
2024-04-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0935-9648 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
29.4 |
Times cited |
|
Open Access |
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| |
Notes |
PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWO- Vlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWO- Vlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. |
Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
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Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9118 |
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| Permanent link to this record |
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Author |
Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. |
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Title |
Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Advanced Materials |
Abbreviated Journal |
Advanced Materials |
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Volume |
|
Issue |
|
Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
| |
Abstract |
A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001206226700001 |
Publication Date |
2024-04-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0935-9648 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
29.4 |
Times cited |
|
Open Access |
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| |
Notes |
PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWOVlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWOVlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. |
Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
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Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9130 |
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Author |
Korneychuk, S.; Guzzinati, G.; Verbeeck, J. |
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Title |
Measurement of the Indirect Band Gap of Diamond with EELS in STEM |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
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Volume |
215 |
Issue |
22 |
Pages |
1800318 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In this work, a simple method to measure the indirect band gap of diamond with electron energy loss spectroscopy (EELS) in transmission electron microscopy (TEM) is showed. The authors discuss the momentum space resolution achievable with EELS and the possibility of deliberately selecting specific transitions of interest. Based on a simple 2 parabolic band model of the band structure, the authors extend our predictions from the direct band gap case discussed in previous work, to the case of an indirect band gap. Finally, the authors point out the emerging possibility to partly reconstruct the band structure with EELS exploiting our simplified model of inelastic scattering and support it with experiments on diamond. |
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Address |
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Corporate Author |
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Wos |
000450818100004 |
Publication Date |
2018-07-30 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1862-6300 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.775 |
Times cited |
6 |
Open Access |
Not_Open_Access |
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| |
Notes |
S.K. and J.V. acknowledge funding from the “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint” of the University of Antwerp. Financial support via the Methusalem “NANO” network is acknowledged. G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint”; Methusalem “NANO” network; Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO); Hercules fund from the Flemish Government; |
Approved |
Most recent IF: 1.775 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:155402 |
Serial |
5138 |
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| Permanent link to this record |
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Author |
Gkanatsiou, A.; Lioutas, C.B.; Frangis, N.; Polychroniadis, E.K.; Prystawko, P.; Leszczynski, M.; Altantzis, T.; Van Tendeloo, G. |
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Title |
Influence of 4H-SiC substrate miscut on the epitaxy and microstructure of AlGaN/GaN heterostructures |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Materials science in semiconductor processing |
Abbreviated Journal |
Mat Sci Semicon Proc |
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| |
Volume |
91 |
Issue |
|
Pages |
159-166 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
AlGaN/GaN heterostructures were grown on “on-axis” and 2° off (0001) 4H-SiC substrates by metalorganic vapor phase epitaxy (MOVPE). Structural characterization was performed by transmission electron microscopy. The dislocation density, being greater in the on-axis case, is gradually reduced in the GaN layer and is forming
dislocation loops in the lower region. Steps aligned along [11̅00] in the off-axis case give rise to simultaneous defect formation. In the on-axis case, an almost zero density of steps is observed, with the main origin of defects probably being the orientation mismatch at the grain boundaries between the small not fully coalesced AlN grains. V-shaped formations are observed in the AlN nucleation layer, but are more frequent in the off-axis case, probably enhanced by the presence of steps. These V-shaped formations are completely overgrown by the GaN layer, during the subsequent deposition, presenting AlGaN areas in the walls of the defect, indicating an interdiffusion between the layers. Finally, at the AlGaN/GaN heterostructure surface in the on-axis case, V-shapes are observed, with the AlN spacer and AlGaN (21% Al) thickness on relaxed GaN exceeding the critical thickness for relaxation. On the other hand, no relaxation in the form of V-shape creation is observed in the off-axis case, probably due to the smaller AlGaN thickness (less than 21% Al). The AlN spacer layer, grown in between the heterostructure, presents a uniform thickness and clear interfaces. |
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Wos |
000454537700022 |
Publication Date |
2018-11-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1369-8001 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.359 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
Funding: This work was supported by the IKY Fellowships of Excellence for Postgraduate Studies in Greece-SIEMENS Program; the Greek General Secretariat for Research and Technology, contract SAE 013/8–2009SE 01380012; and the JU ENIAC Project LAST POWER Large Area silicon carbide Substrates and heteroepitaxial GaN for POWER device applications [grant number 120218]. Also part of the research leading to these results has received funding from the European Union Seventh Framework Program under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative–I3). T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a post-doctoral grant. |
Approved |
Most recent IF: 2.359 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:156200 |
Serial |
5149 |
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| Permanent link to this record |
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Author |
Miotti Bettanini, A.; Ding, L.; Mithieux, J.-D.; Parrens, C.; Idrissi, H.; Schryvers, D.; Delannay, L.; Pardoen, T.; Jacques, P.J. |
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Title |
Influence of M23C6 dissolution on the kinetics of ferrite to austenite transformation in Fe-11Cr-0.06C stainless steel |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Materials & design |
Abbreviated Journal |
Mater Design |
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| |
Volume |
162 |
Issue |
|
Pages |
362-374 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The design of high-strength martensitic stainless steels requires an accurate control over the stability of undesired phases, like carbides and ferrite, which can hamper strength and ductility. Here, the ferrite to austenite transformation in Fe-11Cr-0.06C has been studied with a combined experimental-modelling approach. Experimental observations of the austenization process indicate that austenite growth proceeds in multiple steps, each one characterized by a different transformation rate. DICTRA based modelling reveals that the dissolution of the M23C6 Cr-rich carbides leads to Cr partitioning between austenite and parent phases, which controls the rate of transformation through (i) a soft-impingement effect and (ii) consequent stabilization of the ferrite, which remains untransformed inside chromium-enriched-zones even after prolonged austenization stage. Slow heating rate and smaller initial particle sizes allow the design of ferrite-free microstructure. |
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Place of Publication |
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Language |
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Wos |
000454128400036 |
Publication Date |
2018-12-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0264-1275 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.364 |
Times cited |
3 |
Open Access |
OpenAccess |
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| |
Notes |
The authors thank Professor Anne-Francoise Gourgues-Lorenzon and Helene Godin, Ecole Nationale Superiore des Mines de Paris (MINES ParisTech) for their fruitful discussions. AMB thanks Stijn Van den broek (Universiteit Antwerpen) for the skillful preparation of TEM samples with FIB. The financial support of CBMM (Companhia Brasileira de Metalurgia e Mineracao) is gratefully acknowledged. L. Delannay is mandated by the FNRS-Belgium. Computational resources have been provided by the supercomputing facilities of the UCLouvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en Federation Wallonie Bruxelles (CÉCI) funded by the Fond de la Recherche Scientifique de Belgique (F.R.S.-FNRS) under convention 2.5020.11.; Cbmm; F.r.s.-fnrs, 2.5020.11 ; |
Approved |
Most recent IF: 4.364 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:156721 |
Serial |
5161 |
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| Permanent link to this record |
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Author |
Montero-Sistiaga, M.L.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D.; Vanmeensel, K. |
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Title |
Microstructure and mechanical properties of Hastelloy X produced by HP-SLM (high power selective laser melting) |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Materials & design |
Abbreviated Journal |
Mater Design |
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| |
Volume |
165 |
Issue |
|
Pages |
107598 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
In order to increase the production rate during selective laser melting (SLM), a high power laser with a large beam diameter is used to build fully dense Hastelloy X parts. Compared to SLM with a low power and small diameter beam, the productivity was increased from 6 mm3/s to 16 mm3/s, i.e. 2.6 times faster. Besides the productivity benefit, the influence of the use of a high power laser on the rapid solidification microstructure and concomitant material properties is highlighted. The current paper compares the microstructure and tensile properties of Hastelloy X built with low and high power lasers. The use of a high power laser results in wider and shallower melt pools inducing an enhanced morphological and crystallographic texture along the building direction (BD). In addition, the increased heat input results in coarser sub-grains or high density dislocation walls for samples processed with a high power laser. Additionally, the influence of hot isostatic pressing (HIP) as a post-processing technique was evaluated. After HIP, the tensile fracture strain increased as compared to the strain in the as-built state and helped in obtaining competitive mechanical properties as compared to conventionally processed Hastelloy X parts. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000458259300020 |
Publication Date |
2019-01-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0264-1275 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.364 |
Times cited |
15 |
Open Access |
OpenAccess |
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| |
Notes |
This research was supported by the ENGIE Research and Technology Division. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine. S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. |
Approved |
Most recent IF: 4.364 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:157469 |
Serial |
5176 |
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| Permanent link to this record |
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Author |
Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q. |
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Title |
Study of the Q′ (Q)-phase precipitation in Al–Mg–Si–Cu alloys by quantification of atomic-resolution transmission electron microscopy images and atom probe tomography |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of materials science |
Abbreviated Journal |
J Mater Sci |
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Volume |
54 |
Issue |
10 |
Pages |
7943-7952 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The precipitation mechanism of the Q phase in Al-Mg-Si-Cu alloys has long been the subject of ambiguity and debate since its metastable phase (Q 0) has the same crystal structure and similar lattice parameters as its equilibrium counterparts. In the present work, the evolution of the Q 0 (Q) phase during aging is studied by combination of quantitative atomic-resolution scanning transmission electron microscopy and atom probe tomography. It was found that the transformation from the Q 0 to the Q phase involves changes of the occupancy of Al atoms in atomic columns of the Q 0 (Q) phase. The Al atoms incorporated in the Cu, Si and Mg columns are gradually released into the Al matrix, while mixing between Cu and Si atoms occurs in the Si columns. This transformation process is mainly attributed to the low lattice misfit of the equilibrium Q phase. Besides, the formation of various compositions of the Q phase is due to the different occupancy in the atomic columns of the Q phase. The occupancy changes in the columns of the Q phase are kinetically controlled and are strongly influenced by the alloy composition and aging temperature. |
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Place of Publication |
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Wos |
000460069500043 |
Publication Date |
2019-02-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-2461 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.599 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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| |
Notes |
Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing, cstc2017zdcy-zdzxX0006 ; Fundamental Research Funds for the Central Universities of China, 2018CDGFCL0002 106112017CDJQJ308822 ; Belgian National Fund for Scientific Research; the National Natural Science Foundation of China, 51871035 ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant No. cstc2017zdcyzdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDGFCL0002), the National Natural Science Foundation of China (Grant No. 51871035) and the Foundation for Innovative Research Groups J Mater Sci National Natural Science Foundation of China (Grant No. 51421001). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). |
Approved |
Most recent IF: 2.599 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:158112 |
Serial |
5158 |
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| Permanent link to this record |
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Author |
Pourbabak, S.; Montero-Sistiaga, M.L.; Schryvers, D.; Van Humbeeck, J.; Vanmeensel, K. |
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Title |
Microscopic investigation of as built and hot isostatic pressed Hastelloy X processed by Selective Laser Melting |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Materials characterization |
Abbreviated Journal |
Mater Charact |
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Volume |
153 |
Issue |
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Pages |
366-371 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Microstructural characteristics of Hastelloy X produced by Selective Laser Melting have been investigated by various microscopic techniques in the as built (AB) condition and after hot isostatic pressing (HIP). At sub-grain level the AB material consists of columnar high density dislocation cells while the HIP sample consists of columnar sub-grains with lower dislocation density that originate from the original dislocation cells, contradicting existing models. The sub-grains contain nanoscale precipitates enriched in Al, Ti, Cr and O, located at sub-grain boundaries in the AB condition and within the grains after HIP. At some grain boundaries, micrometer sized chromium carbides are detected after HIP. Micro hardness within the grains was found to decrease after HIP, which was attributed to the decrease in dislocation density due to recovery annealing. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000472696900040 |
Publication Date |
2019-05-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1044-5803 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.714 |
Times cited |
2 |
Open Access |
Not_Open_Access |
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| |
Notes |
S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine and financial support. This work was also made possible through the AUHA13009 grant “TopSPIN for TEM nanostatistics” of the Flemish HERCULES foundation. |
Approved |
Most recent IF: 2.714 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:159974 |
Serial |
5178 |
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Author |
Asapu, R.; Claes, N.; Ciocarlan, R.-G.; Minjauw, M.; Detavernier, C.; Cool, P.; Bals, S.; Verbruggen, S.W. |
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Title |
Electron Transfer and Near-Field Mechanisms in Plasmonic Gold-Nanoparticle-Modified TiO2Photocatalytic Systems |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
ACS applied nano materials |
Abbreviated Journal |
ACS Appl. Nano Mater. |
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Volume |
2 |
Issue |
2 |
Pages |
4067-4074 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL) |
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| |
Abstract |
The major mechanism responsible for plasmonic enhancement of titanium dioxide photocatalysis using gold nanoparticles is still under contention. This work introduces an experimental strategy to disentangle the significance of the charge transfer and near-field mechanisms in plasmonic photocatalysis. By controlling the thickness and conductive nature of a nanoparticle shell that acts as a spacer layer separating the plasmonic metal core from the TiO2 surface, field enhancement or charge transfer effects can be selectively repressed or evoked. Layer-by-layer and in situ polymerization methods are used to synthesize gold core–polymer shell nanoparticles with shell thickness control up to the sub-nanometer level. Detailed optical and electrical characterization supported by near-field simulation models corroborate the trends in photocatalytic activity of the different systems. This approach mainly points at an important contribution of the enhanced near field. |
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Corporate Author |
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Place of Publication |
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Wos |
000477917700006 |
Publication Date |
2019-05-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2574-0970 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
32 |
Open Access |
OpenAccess |
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Notes |
This work was supported by Research Foundation Flanders (FWO). P.C. and R-G.C. acknowledge financial support from FWO (Project No. G038215N). N.C. and S.B. acknowledge financial support from the European Research Council (ERC Starting Grant No. 335078-COLOURATOM). |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:160579 |
Serial |
5184 |
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| Permanent link to this record |
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Author |
Scarabelli, L.; Schumacher, M.; Jimenez de Aberasturi, D.; Merkl, J.‐P.; Henriksen‐Lacey, M.; Milagres de Oliveira, T.; Janschel, M.; Schmidtke, C.; Bals, S.; Weller, H.; Liz‐Marzán, L.M. |
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Title |
Encapsulation of Noble Metal Nanoparticles through Seeded Emulsion Polymerization as Highly Stable Plasmonic Systems |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
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Volume |
29 |
Issue |
29 |
Pages |
1809071 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The implementation of plasmonic nanoparticles in vivo remains hindered by important limitations such as biocompatibility, solubility in biological fluids, and physiological stability. A general and versatile protocol is presented, based on seeded emulsion polymerization, for the controlled encapsulation of gold and silver nanoparticles. This procedure enables the encapsulation of single nanoparticles as well as nanoparticle clusters inside a protecting polymer shell. Specifically, the efficient coating of nanoparticles of both metals is demonstrated, with final dimensions ranging between 50 and 200 nm, i.e., sizes of interest for bio-applications. Such hybrid nanocomposites display extraordinary stability in high ionic strength and oxidizing environments, along with high cellular uptake, and low cytotoxicity. Overall, the prepared nanostructures are promising candidates for plasmonic applications under biologically relevant conditions. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000467109100024 |
Publication Date |
2019-02-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.124 |
Times cited |
19 |
Open Access |
OpenAccess |
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| |
Notes |
L.S. and M.S. contributed equally to this work. This work was supported by the Spanish MINECO (Grant MAT2017-86659-R), by the German Research Foundation (DFG, Grant LA 2901/1-1) and by the European Research Council (Grant 335078 COLOURATOM to S.B). The authors acknowledge funding from the European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M). L.S. acknowledges funding from the American-Italian Cancer Foundation through a Post-Doctoral Research Fellowship. D.J.d.A. thanks MINECO for a Juan de la Cierva fellowship (IJCI-2015-24264). J.P.M. was financed by Verband der Chemischen Industrie e.V. (VCI). The authors thank Dr. Artur Feld, Dr. Andreas Kornowski and Stefan Werner (Institute of Physical Chemistry, University of Hamburg) for their support. |
Approved |
Most recent IF: 12.124 |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:160710 |
Serial |
5190 |
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Author |
Keunecke, M.; Lyzwa, F.; Schwarzbach, D.; Roddatis, V.; Gauquelin, N.; Müller-Caspary, K.; Verbeeck, J.; Callori, S.J.; Klose, F.; Jungbauer, M.; Moshnyaga, V. |
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Title |
High-TCInterfacial Ferromagnetism in SrMnO3/LaMnO3Superlattices |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv. Funct. Mater. |
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Volume |
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Issue |
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Pages |
1808270 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Heterostructures of strongly correlated oxides demonstrate various intriguing and potentially useful interfacial phenomena. LaMnO3/SrMnO3 superlattices are presented showcasing a new high‐temperature ferromagnetic phase with Curie temperature, TC ≈360 K, caused by electron transfer from the surface of the LaMnO3 donor layer into the neighboring SrMnO3 acceptor layer. As a result, the SrMnO3 (top)/LaMnO3 (bottom) interface shows an enhancement of the magnetization as depth‐profiled by polarized neutron reflectometry. The length scale of charge transfer, λTF ≈2 unit cells, is obtained from in situ growth monitoring by optical ellipsometry, supported by optical simulations, and further confirmed by high resolution electron microscopy and spectroscopy. A model of the inhomogeneous distribution of electron density in LaMnO3/SrMnO3 layers along the growth direction is concluded to account for a complex interplay between ferromagnetic and antiferromagnetic layers in superlattices. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000535358900008 |
Publication Date |
2019-02-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616301X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
15.621 |
Times cited |
26 |
Open Access |
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| |
Notes |
The authors thank EU FP7 Framework (Project IFOX) and DFG (SFB 1073, TP B04, A02, Z02) for the financial support. J.V., K.M.C and N.G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge ordering). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. The PNR experiment was funded by the Australian Nuclear Science and Technology Organization (proposal number P3985). |
Approved |
Most recent IF: NA |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:162108 |
Serial |
5294 |
|
| Permanent link to this record |
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Author |
Huygh, S.; Bogaerts, A.; Neyts, E.C. |
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| |
Title |
How Oxygen Vacancies Activate CO2 Dissociation on TiO2 Anatase (001) |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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| |
Volume |
120 |
Issue |
120 |
Pages |
21659-21669 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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| |
Abstract |
The adsorption, dissociation, and diffusion of CO2 on the anatase (001) surface was studied using DFT by means of the generalized gradient approximation using the Perdew−Burcke−Ernzerhof (PBE)-functional and applying corrections for long-range dispersion interactions. Different stable adsorption configurations were identified for the fully oxidized surface. The most stable adsorption configuration is the monodentated carbonate-like structure. Small energy barriers were identified for the conversion of a physisorbed to a chemisorbed configuration.
CO2 dissociation is found to be unfeasible on the stoichiometric surface. The introduction of oxygen vacancy defects gives rise to new highly stable adsorption configurations with a stronger activation of the C−O bonds. This leads to the possibility of exothermic dissociation of CO2 with barriers up to 22.2 kcal/mol,
corresponding to chemical lifetimes of less than 4 s at 300 K. These reactions cause a CO molecule to be formed, which will easily desorb, and the reduced surface to become oxidized. It is clear that oxygen vacancy defects play a key role in the catalytic activity of an anatase (001) surface. Oxygen vacancies play an important role in the dissociation of CO2 on the anatase (001) surface, and will play a significant role in complex problems, such as the catalytic conversion of CO2 to value-added chemicals. |
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Wos |
000384626800055 |
Publication Date |
2016-09-02 |
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ISSN |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
49 |
Open Access |
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Notes |
Stijn Huygh is funded as an aspirant of the Research Foundation Flanders (FWO, project number 11C0115N). This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the UAntwerpen. |
Approved |
Most recent IF: 4.536 |
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Call Number |
PLASMANT @ plasmant @ c:irua:136164 |
Serial |
4291 |
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Author |
Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A. |
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Title |
Influence of the Material Dielectric Constant on Plasma Generation inside Catalyst Pores |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
120 |
Issue |
120 |
Pages |
25923-25934 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma catalysis is gaining increasing interest for various environmental applications, but the crucial question is whether plasma can be created inside catalyst pores and under which conditions. In practice, various catalytic support materials are used, with various dielectric constants. We investigate here the influence of the dielectric constant on the plasma properties inside catalyst pores and in the sheath in front of the pores, for various pore sizes. The calculations are performed by a two-dimensional fluid model for an atmospheric pressure dielectric barrier discharge in helium. The electron impact ionization rate, electron temperature, electron and ion density, as well as the potential distribution and surface charge density, are analyzed for a better understanding of the discharge behavior inside catalyst pores. The results indicate that, in a 100 μm pore, the electron impact ionization in the pore, which is characteristic for the plasma generation inside the pore, is greatly enhanced for dielectric constants below 300. Smaller pore sizes only yield enhanced ionization for smaller dielectric constants, i.e., up to εr = 200, 150, and 50 for pore sizes of 50, 30, and 10 μm. Thus, the most common catalyst supports, i.e., Al2O3 and SiO2, which have dielectric constants around εr = 8−11 and 4.2, respectively, should allow more easily that microdischarges can be formed inside catalyst pores, even for smaller pore sizes. On the other hand, ferroelectric materials with dielectric constants above 300 never seem to yield plasma enhancement inside catalyst pores, not even for 100 μm pore sizes. Furthermore, it is clear that the dielectric constant of the material has a large effect on the extent of plasma enhancement inside the catalyst pores, especially in the range between εr = 4 and εr = 200. The obtained results are explained in detail based on the surface charge density at the pore walls,
and the potential distribution and electron temperature inside and above the pores. The results obtained with this model are
important for plasma catalysis, as the production plasma species in catalyst pores might affect the catalyst properties, and thus
improve the applications of plasma catalysis. |
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Wos |
000388429100029 |
Publication Date |
2016-11-17 |
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Edition |
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ISSN |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
34 |
Open Access |
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Notes |
This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant G.0217.14N), the National Natural Science Foundation of China (Grant 11405019), and the China Postdoctoral Science Foundation (Grant 2015T80244). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the University of Antwerp. |
Approved |
Most recent IF: 4.536 |
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Call Number |
PLASMANT @ plasmant @ c:irua:138602 |
Serial |
4319 |
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Author |
De Bie, C.; van Dijk, J.; Bogaerts, A. |
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Title |
CO2Hydrogenation in a Dielectric Barrier Discharge Plasma Revealed |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
120 |
Issue |
120 |
Pages |
25210-25224 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The hydrogenation of carbon dioxide in a dielectric barrier discharge plasma is studied with a one-dimensional fluid model. The spatially averaged densities of the most important end products formed in the CO2/H2 mixture are determined as a function of the initial gas mixing ratio. CO and H2O are found to be present at the highest densities and to a lower content also CH4, C2H6, CH2O, CH3OH, O2, and some other higher hydrocarbons and oxygenates. The main underlying reaction
pathways for the conversion of the inlet gases and the formation of CO, CH4, CH2O, and CH3OH are pointed out for various gas mixing ratios. The CO2 conversion and the production of value added products is found to be quite low, also in comparison to a CO2/CH4 mixture, and this can be explained by the model. |
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Wos |
000387737900007 |
Publication Date |
2016-11-10 |
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Series Issue |
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Edition |
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ISSN |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
16 |
Open Access |
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Notes |
Federaal Wetenschapsbeleid; Fonds Wetenschappelijk Onderzoek; |
Approved |
Most recent IF: 4.536 |
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Call Number |
PLASMANT @ plasmant @ c:irua:140082 c:irua:139167 |
Serial |
4414 |
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Author |
Verlackt, C.C.W.; Van Boxem, W.; Dewaele, D.; Lemière, F.; Sobott, F.; Benedikt, J.; Neyts, E.C.; Bogaerts, A. |
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Title |
Mechanisms of Peptide Oxidation by Hydroxyl Radicals: Insight at the Molecular Scale |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
121 |
Issue |
121 |
Pages |
5787-5799 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Molecular dynamics (MD) simulations were performed to provide atomic scale insight in the initial interaction between hydroxyl radicals (OH) and peptide systems in solution. These OH radicals are representative reactive oxygen species produced by cold atmospheric plasmas. The use of plasma for biomedical applications is gaining increasing interest, but the fundamental mechanisms behind the plasma modifications still remain largely elusive. This study helps to gain more insight in the underlying mechanisms of plasma medicine but is also more generally applicable to peptide oxidation, of interest for other applications. Combining both reactive and nonreactive MD simulations, we are able to elucidate the reactivity of the amino acids inside the peptide systems and their effect on their structure up to 1 μs. Additionally, experiments were performed, treating the simulated peptides with a plasma jet. The computational results presented here correlate well with the obtained experimental data and highlight the importance of the chemical environment for the reactivity of the individual amino acids, so that specific amino acids are attacked in higher numbers than expected. Furthermore, the long time scale simulations suggest that a single oxidation has an effect on the 3D conformation due to an increase in hydrophilicity and intra- and intermolecular interactions. |
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Wos |
000396969900037 |
Publication Date |
2017-03-16 |
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Series Issue |
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Edition |
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ISSN |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
5 |
Open Access |
OpenAccess |
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Notes |
Fonds Wetenschappelijk Onderzoek, G012413N ; |
Approved |
Most recent IF: 4.536 |
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Call Number |
PLASMANT @ plasmant @ c:irua:142202 |
Serial |
4537 |
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Author |
Berthelot, A.; Bogaerts, A. |
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Title |
Modeling of CO2Splitting in a Microwave Plasma: How to Improve the Conversion and Energy Efficiency |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
121 |
Issue |
121 |
Pages |
8236-8251 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Microwave plasmas are one of the most promising techniques for CO2 conversion into value-added chemicals and fuels since they are very energy efficient. Nevertheless, experiments show that this high energy efficiency is only reached at low pressures and significantly drops toward atmospheric pressure, which is a clear limitation for industrial applications. In this paper, we use a zerodimensional reaction kinetics model to simulate a CO2 microwave plasma in a pressure range from 50 mbar to 1 bar, in order to evaluate the reasons for this decrease in energy efficiency at atmospheric pressure. The code includes a detailed description of the vibrational kinetics of CO2, CO, and O2 as well as the energy exchanges between them because the vibrational kinetics is known to be crucial for energy efficient CO2 splitting. First, we use a self-consistent gas temperature calculation in order to assess the key performance indicators for CO2 splitting, i.e., the CO2 conversion and corresponding energy efficiency. Our results indicate that lower pressures and higher power densities lead to more vibrational excitation, which is beneficial for the conversion. We also demonstrate the key role of the gas temperature. The model predicts the highest conversion and energy efficiencies at pressures around 300 mbar, which is in agreement with experiments from the literature. We also show the beneficial aspect of fast gas cooling in the afterglow at high pressure. In a second step, we study in more detail the effects of pressure, gas temperature, and power density on the vibrational distribution function and on the dissociation and recombination mechanisms of CO2, which define the CO2 splitting efficiency. This study allows us to identify the limiting factors of CO2 conversion and to propose potential solutions to improve the process. |
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Wos |
000400039300002 |
Publication Date |
2017-04-20 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
47 |
Open Access |
OpenAccess |
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Notes |
Federaal Wetenschapsbeleid; |
Approved |
Most recent IF: 4.536 |
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Call Number |
PLASMANT @ plasmant @ c:irua:142809 |
Serial |
4567 |
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