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Author | Vandemeulebroucke, D.; Batuk, M.; Hajizadeh, A.; Wastiaux, M.; Roussel, P.; Hadermann, J. | ||||
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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Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
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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English | Wos | 001174840900001 | Publication Date | 2024-02-20 |
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ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 8.6 | Times cited | Open Access | Not_Open_Access | |
Notes | Universiteit Antwerpen, BOF TOP 38689 ; Fonds Wetenschappelijk Onderzoek, I003218N ; European Commission NanED, 956099 ; | Approved | Most recent IF: 8.6; 2024 IF: 9.466 | ||
Call Number | EMAT @ emat @c:irua:204354 | Serial | 8997 | ||
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Author | Heirman, P.; Verloy, R.; Baroen, J.; Privat-Maldonado, A.; Smits, E.; Bogaerts, A. | ||||
Title | Liquid treatment with a plasma jet surrounded by a gas shield: effect of the treated substrate and gas shield geometry on the plasma effluent conditions | Type | A1 Journal article | ||
Year | 2024 | Publication | Journal of physics: D: applied physics | Abbreviated Journal | J. Phys. D: Appl. Phys. |
Volume | 57 | Issue | 11 | Pages | 115204 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Center for Oncological Research (CORE) | ||||
Abstract | The treatment of a well plate by an atmospheric pressure plasma jet is common for<italic>in vitro</italic>plasma medicine research. Here, reactive species are largely produced through the mixing of the jet effluent with the surrounding atmosphere. This mixing can be influenced not only by the ambient conditions, but also by the geometry of the treated well. To limit this influence and control the atmosphere, a shielding gas is sometimes applied. However, the interplay between the gas shield and the well geometry has not been investigated. In this work, we developed a 2D-axisymmetric computational fluid dynamics model of the kINPen plasma jet, to study the mixing of the jet effluent with the surrounding atmosphere, with and without gas shield. Our computational and experimental results show that the choice of well type can have a significant influence on the effluent conditions, as well as on the effectiveness of the gas shield. Furthermore, the geometry of the shielding gas device can substantially influence the mixing as well. Our results provide a deeper understanding of how the choice of setup geometry can influence the plasma treatment, even when all other operating parameters are unchanged. | ||||
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Wos | 001127372200001 | Publication Date | 2024-03-15 | |
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ISSN | 0022-3727 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.4 | Times cited | Open Access | Not_Open_Access | |
Notes | Fund for Scientific Research Flanders, 1100421N ; | Approved | Most recent IF: 3.4; 2024 IF: 2.588 | ||
Call Number | PLASMANT @ plasmant @c:irua:201999 | Serial | 8977 | ||
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Author | Kelly, S.; Mercer, E.; Gorbanev, Y.; Fedirchyk, I.; Verheyen, C.; Werner, K.; Pullumbi, P.; Cowley, A.; Bogaerts, A. | ||||
Title | Plasma-based conversion of martian atmosphere into life-sustaining chemicals: The benefits of utilizing martian ambient pressure | Type | A1 Journal article | ||
Year | 2024 | Publication | Journal of CO2 utilization | Abbreviated Journal | Journal of CO2 Utilization |
Volume | 80 | Issue | Pages | 102668 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We explored the potential of plasma-based In-Situ Resource Utilization (ISRU) for Mars through the conversion of Martian atmosphere (~96% CO2, 2% N2, and 2% Ar) into life-sustaining chemicals. As the Martian surface pressure is about 1% of the Earth’s surface pressure, it is an ideal environment for plasma-based gas conversion using microwave reactors. At 1000 W and 10 Ln/min (normal liters per minute), we produced ~76 g/h of O2 and ~3 g/h of NOx using a 2.45 GHz waveguided reactor at 25 mbar, which is ~3.5 times Mars ambient pressure. The energy cost required to produce O2 was ~0.013 kWh/g, which is very promising compared to recently concluded MOXIE experiments on the Mars surface. This marks a crucial step towards realizing the extension of human exploration. | ||||
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Wos | 001156084300001 | Publication Date | 2024-01-09 | |
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ISSN | 2212-9820 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 7.7 | Times cited | Open Access | Not_Open_Access | |
Notes | We acknowledge financial support by a European Space Agency (ESA) Open Science Innovation Platform study (contract no. 4000137001/21/NL/GLC/ov), the European Marie Skłodowska-Curie Individual Fellowship ‘‘PENFIX’’ within Horizon 2020 (grant no. 838181), the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Program (grant no. 810182; SCOPE ERC Synergy project), the Excellence of Science FWOFNRS PLASyntH2 project (FWO grant no. G0I1822N and EOS no. 4000751) and the Methusalem project of the University of Antwerp. | Approved | Most recent IF: 7.7; 2024 IF: 4.292 | ||
Call Number | PLASMANT @ plasmant @c:irua:202389 | Serial | 8986 | ||
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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. | ||||
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 |
Volume | 185 | Issue | Pages | 186-206 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
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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Wos | 001154261100001 | Publication Date | 2023-12-24 | |
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ISSN | 1005-0302 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 10.9 | Times cited | Open Access | Not_Open_Access | |
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 | ||
Call Number | EMAT @ emat @c:irua:202392 | Serial | 8981 | ||
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Author | Hofer, C.; Gao, C.; Chennit, T.; Yuan, B.; Pennycook, T.J. | ||||
Title | Phase offset method of ptychographic contrast reversal correction | Type | A1 Journal article | ||
Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | Issue | Pages | 113922 | ||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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Wos | 001164447000001 | Publication Date | 2024-01-08 | |
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ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 2.2 | Times cited | Open Access | Not_Open_Access | |
Notes | FWO, G013122N ; Horizon 2020 Framework Programme; European Research Council, 802123-HDEM ; European Research Council; | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:202379 | Serial | 8988 | ||
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Author | Bissonnette-Dulude, J.; Heirman, P.; Coulombe, S.; Bogaerts, A.; Gervais, T.; Reuter, S. | ||||
Title | Coupling the COST reference plasma jet to a microfluidic device: a computational study | Type | A1 Journal article | ||
Year | 2024 | Publication | Plasma sources science and technology | Abbreviated Journal | Plasma Sources Sci. Technol. |
Volume | 33 | Issue | 1 | Pages | 015001 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The use of microfluidic devices in the field of plasma-liquid interaction can unlock unique possibilities to investigate the effects of plasma-generated reactive species for environmental and biomedical applications. So far, very little simulation work has been performed on microfluidic devices in contact with a plasma source. We report on the modelling and computational simulation of physical and chemical processes taking place in a novel plasma-microfluidic platform. The main production and transport pathways of reactive species both in plasma and liquid are modelled by a novel modelling approach that combines 0D chemical kinetics and 2D transport mechanisms. This combined approach, applicable to systems where the transport of chemical species occurs in unidirectional flows at high Péclet numbers, decreases calculation times considerably compared to regular 2D simulations. It takes advantage of the low computational time of the 0D reaction models while providing spatial information through multiple plug-flow simulations to yield a quasi-2D model. The gas and liquid flow profiles are simulated entirely in 2D, together with the chemical reactions and transport of key chemical species. The model correctly predicts increased transport of hydrogen peroxide into the liquid when the microfluidic opening is placed inside the plasma effluent region, as opposed to inside the plasma region itself. Furthermore, the modelled hydrogen peroxide production and transport in the microfluidic liquid differs by less than 50% compared with experimental results. To explain this discrepancy, the limits of the 0D–2D combined approach are discussed. | ||||
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Wos | 001136607100001 | Publication Date | 2024-01-01 | |
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ISSN | 0963-0252 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.8 | Times cited | Open Access | Not_Open_Access | |
Notes | Natural Sciences and Engineering Research Council of Canada, RGPIN-06820 ; FWO, 1100421N ; McGill University, the TransMedTech Institute; | Approved | Most recent IF: 3.8; 2024 IF: 3.302 | ||
Call Number | PLASMANT @ plasmant @c:irua:202783 | Serial | 8990 | ||
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Author | Mary Joy, R.; Pobedinskas, P.; Baule, N.; Bai, S.; Jannis, D.; Gauquelin, N.; Pinault-Thaury, M.-A.; Jomard, F.; Sankaran, K.J.; Rouzbahani, R.; Lloret, F.; Desta, D.; D’Haen, J.; Verbeeck, J.; Becker, M.F.; Haenen, K. | ||||
Title | The effect of microstructure and film composition on the mechanical properties of linear antenna CVD diamond thin films | Type | A1 Journal article | ||
Year | 2024 | Publication | Acta materialia | Abbreviated Journal | Acta Materialia |
Volume | 264 | Issue | Pages | 119548 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | This study reports the impact of film microstructure and composition on the Young’s modulus and residual stress in nanocrystalline diamond (NCD) thin films ( thick) grown on silicon substrates using a linear antenna microwave plasma-enhanced chemical vapor deposition (CVD) system. Combining laser acoustic wave spectroscopy to determine the elastic properties with simple wafer curvature measurements, a straightforward method to determine the intrinsic stress in NCD films is presented. Two deposition parameters are varied: (1) the substrate temperature from 400 °C to 900 °C, and (2) the [P]/[C] ratio from 0 ppm to 8090 ppm in the H2/CH4/CO2/PH3 diamond CVD plasma. The introduction of PH3 induces a transition in the morphology of the diamond film, shifting from NCD with larger grains to ultra-NCD with a smaller grain size, concurrently resulting in a decrease in Young’s modulus. Results show that the highest Young’s modulus of (113050) GPa for the undoped NCD deposited at 800 °C is comparable to single crystal diamond, indicating that NCD with excellent mechanical properties is achievable with our process for thin diamond films. Based on the film stress results, we propose the origins of tensile intrinsic stress in the diamond films. In NCD, the tensile intrinsic stress is attributed to larger grain size, while in ultra-NCD films the tensile intrinsic stress is due to grain boundaries and impurities. | ||||
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Wos | 001126632800001 | Publication Date | 2023-11-23 | |
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ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.4 | Times cited | Open Access | Not_Open_Access | |
Notes | This work was financially supported by the Special Research Fund (BOF) via Methusalem NANO network, the Research Foundation – Flanders (FWO) via Project G0D4920N, and the CORNET project nr 263-EN “ULTRAHARD: Ultrahard optical diamond coatings” (2020–2021). | Approved | Most recent IF: 9.4; 2024 IF: 5.301 | ||
Call Number | EMAT @ emat @c:irua:202169 | Serial | 8989 | ||
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Author | Manaigo, F.; Rouwenhorst, K.; Bogaerts, A.; Snyders, R. | ||||
Title | Feasibility study of a small-scale fertilizer production facility based on plasma nitrogen fixation | Type | A1 Journal Article | ||
Year | 2024 | Publication | Energy Conversion and Management | Abbreviated Journal | Energy Conversion and Management |
Volume | 302 | Issue | Pages | 118124 | |
Keywords | A1 Journal Article; Plasma-based nitrogen fixation Haber-Bosch Feasibility study Fertilizer production; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
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Wos | 001171038200001 | Publication Date | 2024-01-25 | |
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ISSN | 0196-8904 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 10.4 | Times cited | Open Access | Not_Open_Access | |
Notes | This research is supported by the FNRS-FWO project ‘‘NITROPLASM’’, EOS O005118F. The authors thank Dr. L. Hollevoet (KU Leuven) for the draft reviewing and for providing additional information on the lean NO???? trap. | Approved | Most recent IF: 10.4; 2024 IF: 5.589 | ||
Call Number | PLASMANT @ plasmant @c:irua:204351 | Serial | 8992 | ||
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Author | Wang, K.; Ceulemans, S.; Zhang, H.; Tsonev, I.; Zhang, Y.; Long, Y.; Fang, M.; Li, X.; Yan, J.; Bogaerts, A. | ||||
Title | Inhibiting recombination to improve the performance of plasma-based CO2 conversion | Type | A1 Journal Article | ||
Year | 2024 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chemical Engineering Journal |
Volume | 481 | Issue | Pages | 148684 | |
Keywords | A1 Journal Article; Plasma-based CO2 splitting Recombination reactions In-situ gas sampling Fluid dynamics modeling Kinetics modeling Afterglow quenching; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | Warm plasma offers a promising route for CO2 splitting into valuable CO, yet recombination reactions of CO with oxygen, forming again CO2, have recently emerged as critical limitation. This study combines experiments and fluid dynamics + chemical kinetics modelling to comprehensively analyse the recombination reactions upon CO2 splitting in an atmospheric plasmatron. We introduce an innovative in-situ gas sampling technique, enabling 2D spatial mapping of gas product compositions and temperatures, experimentally confirming for the first time the substantial limiting effect of CO recombination reactions in the afterglow region. Our results show that the CO mole fraction at a 5 L/min flow rate drops significantly from 11.9 % at a vertical distance of z = 20 mm in the afterglow region to 8.6 % at z = 40 mm. We constructed a comprehensive 2D model that allows for spatial reaction rates analysis incorporating crucial reactions, and we validated it to kinetically elucidate this phenomenon. CO2 +M⇌O+CO+M and CO2 +O⇌CO+O2 are the dominant reactions, with the forward reactions prevailing in the plasma region and the backward reactions becoming prominent in the afterglow region. These results allow us to propose an afterglow quenching strategy for performance enhancement, which is further demonstrated through a meticulously developed plasmatron reactor with two-stage cooling. Our approach substantially increases the CO2 conversion (e.g., from 6.6 % to 19.5 % at 3 L/min flow rate) and energy efficiency (from 13.5 % to 28.5 %, again at 3 L/min) and significantly shortens the startup time (from ~ 150 s to 25 s). Our study underscores the critical role of inhibiting recombination reactions in plasma-based CO2 conversion and offers new avenues for performance enhancement. | ||||
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Wos | 001168999200001 | Publication Date | 2024-01-10 | |
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ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 15.1 | Times cited | Open Access | Not_Open_Access | |
Notes | Key Research and Development Program of Zhejiang Province, 2023C03129 ; Vlaamse regering; European Research Council; National Natural Science Foundation of China, 51976191 52276214 ; Horizon 2020 Framework Programme; Fonds De La Recherche Scientifique – FNRS; Fonds Wetenschappelijk Onderzoek, 1101524N ; Vlaams Supercomputer Centrum; Horizon 2020, 101081162 810182 ; European Research Council; | Approved | Most recent IF: 15.1; 2024 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:204352 | Serial | 8993 | ||
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Author | Lobato, I.; Friedrich, T.; Van Aert, S. | ||||
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 |
Volume | 10 | Issue | 1 | Pages | 10 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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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Wos | 001138183000001 | Publication Date | 2024-01-09 | |
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ISSN | 2057-3960 | ISBN | Additional Links | UA library record; WoS full record | |
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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 | ||
Call Number | EMAT @ emat @c:irua:202714 | Serial | 8994 | ||
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Author | Morais, E.; Bogaerts, A. | ||||
Title | Modelling the dynamics of hydrogen synthesis from methane in nanosecond‐pulsed plasmas | Type | A1 Journal article | ||
Year | 2024 | Publication | Plasma processes and polymers | Abbreviated Journal | Plasma Processes & Polymers |
Volume | 21 | Issue | 1 | Pages | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | A chemical kinetics model was developed to characterise the gas‐phase dynamics of H<sub>2</sub>production in nanosecond‐pulsed CH<sub>4</sub>plasmas. Pulsed behaviour was observed in the calculated electric field, electron temperature and species densities at all pressures. The model agrees reasonably with experimental results, showing CH<sub>4</sub>conversion at 30% and C<sub>2</sub>H<sub>2</sub>and H<sub>2</sub>as major products. The underlying mechanisms in CH<sub>4</sub>dissociation and H<sub>2</sub>formation were analysed, highlighting the large contribution of vibrationally excited CH<sub>4</sub>and H<sub>2</sub>to coupling energy from the plasma into gas‐phase heating, and revealing that H<sub>2</sub>synthesis is not affected by applied pressure, with selectivity remaining unchanged at ~42% in the 1–5 bar range. | ||||
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Wos | 001091258700001 | Publication Date | 2023-10-27 | |
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ISSN | 1612-8850 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.5 | Times cited | Open Access | Not_Open_Access | |
Notes | We gratefully acknowledge financial support by the Flemish Government through the Moonshot cSBO project “Power‐to‐Olefins” (P2O; HBC.2020.2620) and funding from the Independent Research Fund Denmark (project nr. 0217‐00231B). | Approved | Most recent IF: 3.5; 2024 IF: 2.846 | ||
Call Number | PLASMANT @ plasmant @c:irua:201192 | Serial | 8983 | ||
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Author | Şentürk, DG.; Yu, CP.; De Backer, A.; Van Aert, S. | ||||
Title | Atom counting from a combination of two ADF STEM images | Type | A1 Journal article | ||
Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 255 | Issue | Pages | 113859 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | To understand the structure–property relationship of nanostructures, reliably quantifying parameters, such as the number of atoms along the projection direction, is important. Advanced statistical methodologies have made it possible to count the number of atoms for monotype crystalline nanoparticles from a single ADF STEM image. Recent developments enable one to simultaneously acquire multiple ADF STEM images. Here, we present an extended statistics-based method for atom counting from a combination of multiple statistically independent ADF STEM images reconstructed from non-overlapping annular detector collection regions which improves the accuracy and allows one to retrieve precise atom-counts, especially for images acquired with low electron doses and multiple element structures. | ||||
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Wos | 001089064200001 | Publication Date | 2023-09-23 | |
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ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N, G0A7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:201008 | Serial | 8964 | ||
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Author | Meng, S.; Li, S.; Sun, S.; Bogaerts, A.; Liu, Y.; Yi, Y. | ||||
Title | NH3 decomposition for H2 production by thermal and plasma catalysis using bimetallic catalysts | Type | A1 Journal article | ||
Year | 2024 | Publication | Chemical engineering science | Abbreviated Journal | Chemical Engineering Science |
Volume | 283 | Issue | Pages | 119449 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma catalysis has emerged as a promising approach for driving thermodynamically unfavorable chemical reactions. Nevertheless, comprehending the mechanisms involved remains a challenge, leading to uncertainty about whether the optimal catalyst in plasma catalysis aligns with that in thermal catalysis. In this research, we explore this question by studying monometallic catalysts (Fe, Co, Ni and Mo) and bimetallic catalysts (Fe-Co, Mo- Co, Fe-Ni and Mo-Ni) in both thermal catalytic and plasma catalytic NH3 decomposition. Our findings reveal that the Fe-Co bimetallic catalyst exhibits the highest activity in thermal catalysis, the Fe-Ni bimetallic catalyst outperforms others in plasma catalysis, indicating a discrepancy between the optimal catalysts for the two catalytic modes in NH3 decomposition. Comprehensive catalyst characterization, kinetic analysis, temperature program surface reaction experiments and plasma diagnosis are employed to discuss the key factors influencing NH3 decomposition performance. |
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Wos | 001105312500001 | Publication Date | 2023-10-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2509 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.7 | Times cited | Open Access | Not_Open_Access | |
Notes | Universiteit Antwerpen, 32249 ; National Natural Science Foundation of China, 21503032 ; PetroChina Innovation Foundation, 2018D-5007-0501 ; | Approved | Most recent IF: 4.7; 2024 IF: 2.895 | ||
Call Number | PLASMANT @ plasmant @c:irua:201009 | Serial | 8967 | ||
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Author | Slaets, J.; Loenders, B.; Bogaerts, A. | ||||
Title | Plasma-based dry reforming of CH4: Plasma effects vs. thermal conversion | Type | A1 Journal article | ||
Year | 2024 | Publication | Fuel | Abbreviated Journal | Fuel |
Volume | 360 | Issue | Pages | 130650 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this work we evaluate the chemical kinetics of dry reforming of methane in warm plasmas (1000–4000 K) using modelling with a newly developed chemistry set, for a broad range of parameters (temperature, power density and CO2/CH4 ratio). We compare the model against thermodynamic equilibrium concentrations, serving as validation of the thermal chemical kinetics. Our model reveals that plasma-specific reactions (i.e., electron impact collisions) accelerate the kinetics compared to thermal conversion, rather than altering the overall kinetics pathways and intermediate products, for gas temperatures below 2000 K. For higher temperatures, the kinetics are dominated by heavy species collisions and are strictly thermal, with negligible influence of the electrons and ions on the overall kinetics. When studying the effects of different gas mixtures on the kinetics, we identify important intermediate species, side reactions and side products. The use of excess CO2 leads to H2O formation, at the expense of H2 formation, and the CO2 conversion itself is limited, only approaching full conversion near 4000 K. In contrast, full conversion of both reactants is only kinetically limited for mixtures with excess CH4, which also gives rise to the formation of C2H2, alongside syngas. Within the given parameter space, our model predicts the 30/70 ratio of CO2/CH4 to be the most optimal for syngas formation with a H2/CO ratio of 2. | ||||
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Wos | 001138077700001 | Publication Date | 2023-12-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0016-2361 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.4 | Times cited | Open Access | Not_Open_Access | |
Notes | This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 810182 – SCOPE ERC Synergy project), the Catalisti-ICON project BluePlasma (Project No. HBC.2022.0445), the FWO-SBO project PlasMaCatDESIGN (FWO Grant ID S001619N), the Independent Research Fund Denmark (Project No. 0217-00231B) and through long-term structural funding (Methusalem). The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government. We also thank Bart Wanten, Roel Michiels, Pepijn Heirman, Claudia Verheyen, dr. Senne Van Alphen, dr. Elise Vervloessem, dr. Kevin van ’t Veer, dr. Joshua Boothroyd, dr. Omar Biondo and dr. Eduardo Morais for their expertise and feedback regarding the kinetics scheme. | Approved | Most recent IF: 7.4; 2024 IF: 4.601 | ||
Call Number | PLASMANT @ plasmant @c:irua:201669 | Serial | 8973 | ||
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Author | Grünewald, L.; Chezganov, D.; De Meyer, R.; Orekhov, A.; Van Aert, S.; Bogaerts, A.; Bals, S.; Verbeeck, J. | ||||
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 |
Volume | Issue | Pages | |||
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
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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Wos | 001168639900001 | Publication Date | 2024-02-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2365-709X | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 6.8 | Times cited | Open Access | OpenAccess | |
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 | ||
Call Number | EMAT @ emat @c:irua:204363 | Serial | 8995 | ||
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Author | Şentürk, D.G.; De Backer, A.; Van Aert, S. | ||||
Title | Element specific atom counting for heterogeneous nanostructures: Combining multiple ADF STEM images for simultaneous thickness and composition determination | Type | A1 Journal Article | ||
Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 259 | Issue | Pages | 113941 | |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | In this paper, a methodology is presented to count the number of atoms in heterogeneous nanoparticles based on the combination of multiple annular dark field scanning transmission electron microscopy (ADF STEM) images. The different non-overlapping annular detector collection regions are selected based on the principles of optimal statistical experiment design for the atom-counting problem. To count the number of atoms, the total intensities of scattered electrons for each atomic column, the so-called scattering cross-sections, are simultaneously compared with simulated library values for the different detector regions by minimising the squared differences. The performance of the method is evaluated for simulated Ni@Pt and Au@Ag core-shell nanoparticles. Our approach turns out to be a dose efficient alternative for the investigation of beam-sensitive heterogeneous materials as compared to the combination of ADF STEM and energy dispersive X-ray spectroscopy. | ||||
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Wos | Publication Date | 2024-02-19 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record | |
Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0346.21N, GOA7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:204353 | Serial | 8996 | ||
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Author | Gerrits, N.; Jackson, B.; Bogaerts, A. | ||||
Title | Accurate Reaction Probabilities for Translational Energies on Both Sides of the Barrier of Dissociative Chemisorption on Metal Surfaces | Type | A1 Journal Article | ||
Year | 2024 | Publication | The Journal of Physical Chemistry Letters | Abbreviated Journal | J. Phys. Chem. Lett. |
Volume | 15 | Issue | 9 | Pages | 2566-2572 |
Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | Molecular dynamics simulations are essential for a better understanding of dissociative chemisorption on metal surfaces, which is often the rate-controlling step in heterogeneous and plasma catalysis. The workhorse quasi-classical trajectory approach ubiquitous in molecular dynamics is able to accurately predict reactivity only for high translational and low vibrational energies. In contrast, catalytically relevant conditions generally involve low translational and elevated vibrational energies. Existing quantum dynamics approaches are intractable or approximate as a result of the large number of degrees of freedom present in molecule−metal surface reactions. Here, we extend a ring polymer molecular dynamics approach to fully include, for the first time, the degrees of freedom of a moving metal surface. With this approach, experimental sticking probabilities for the dissociative chemisorption of methane on Pt(111) are reproduced for a large range of translational and vibrational energies by including nuclear quantum effects and employing full-dimensional simulations. | ||||
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Wos | 001177959900001 | Publication Date | 2024-03-07 | |
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ISSN | 1948-7185 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 5.7 | Times cited | Open Access | ||
Notes | Nick Gerrits has been financially supported through a Dutch Research Council (NWO) Rubicon grant (019.202EN.012). The computational resources and services used in this work were provided by the high performance computing (HPC) core facility CalcUA of the Universiteit Antwerpen and the Flemish Supercomputer Center (VSC) funded by the Research Foundation−Flanders (FWO) and the Flemish Government. The authors thank Mark Somers for useful discussions. | Approved | Most recent IF: 5.7; 2024 IF: 9.353 | ||
Call Number | PLASMANT @ plasmant @c:irua:204818 | Serial | 9114 | ||
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Author | De Meyer, R.; Gorbanev, Y.; Ciocarlan, R.-G.; Cool, P.; Bals, S.; Bogaerts, A. | ||||
Title | Importance of plasma discharge characteristics in plasma catalysis: Dry reforming of methane vs. ammonia synthesis | Type | A1 Journal Article | ||
Year | 2024 | Publication | Chemical Engineering Journal | Abbreviated Journal | Chemical Engineering Journal |
Volume | 488 | Issue | Pages | 150838 | |
Keywords | A1 Journal Article; Gas conversion Dry reforming of methane Ammonia Microdischarges Dielectric barrier discharge; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | Plasma catalysis is a rapidly growing field, often employing a packed-bed dielectric barrier discharge plasma reactor. Such dielectric barrier discharges are complex, especially when a packing material (e.g., a catalyst) is introduced in the discharge volume. Catalysts are known to affect the plasma discharge, though the underlying mechanisms influencing the plasma physics are not fully understood. Moreover, the effect of the catalysts on the plasma discharge and its subsequent effect on the overall performance is often overlooked. In this work, we deliberately design and synthesize catalysts to affect the plasma discharge in different ways. These Ni or Co alumina-based catalysts are used in plasma-catalytic dry reforming of methane and ammonia synthesis. Our work shows that introducing a metal to the dielectric packing can affect the plasma discharge, and that the distribution of the metal is crucial in this regard. Further, the altered discharge can greatly influence the overall performance. In an atmospheric pressure dielectric barrier discharge reactor, this apparently more uniform plasma yields a significantly better performance for ammonia synthesis compared to the more conventional filamentary discharge, while it underperforms in dry reforming of methane. This study stresses the importance of analyzing the plasma discharge in plasma catalysis experiments. We hope this work encourages a more critical view on the plasma discharge characteristics when studying various catalysts in a plasma reactor. | ||||
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Wos | Publication Date | 2024-03-30 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record | |
Impact Factor | 15.1 | Times cited | Open Access | ||
Notes | This research was supported through long-term structural funding (Methusalem FFB15001C) and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme with grant agreement No 810182 (SCOPE ERC Synergy project) and with grant agreement No 815128 (REALNANO). We acknowledge the practical contribution of Senne Van Doorslaer. | Approved | Most recent IF: 15.1; 2024 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:205154 | Serial | 9115 | ||
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Author | Faraji, F.; Neyts, E.C.; Milošević, M.V.; Peeters, F.M. | ||||
Title | Comment on “Misinterpretation of the Shuttleworth equation” | Type | A1 Journal Article | ||
Year | 2024 | Publication | Scripta Materialia | Abbreviated Journal | Scripta Materialia |
Volume | 250 | Issue | Pages | 116186 | |
Keywords | A1 Journal Article; CMT | ||||
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Wos | Publication Date | 2024-05-24 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-6462 | ISBN | Additional Links | ||
Impact Factor | 6 | Times cited | Open Access | ||
Notes | Research Foundation Flanders; | Approved | Most recent IF: 6; 2024 IF: 3.747 | ||
Call Number | UA @ lucian @ CMT | Serial | 9116 | ||
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Author | Gorbanev, Y.; Fedirchyk, I.; Bogaerts, A. | ||||
Title | Plasma catalysis in ammonia production and decomposition: Use it, or lose it? | Type | A1 Journal Article | ||
Year | 2024 | Publication | Current Opinion in Green and Sustainable Chemistry | Abbreviated Journal | Current Opinion in Green and Sustainable Chemistry |
Volume | 47 | Issue | Pages | 100916 | |
Keywords | A1 Journal Article; Plasma Nitrogen fixation Ammonia Plasma catalysis Production and decomposition; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | The combination of plasma with catalysis for the synthesis and decomposition of NH3 is an attractive route to the production of carbon-neutral fertiliser and energy carriers and its conversion into H2. Recent years have seen fast developments in the field of plasma-catalytic NH3 life cycle. This work summarises the most recent advances in plasma-catalytic and related NH3-focussed processes, identifies some of the most important discoveries, and addresses plausible strategies for future developments in plasma-based NH3 technology. | ||||
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Wos | Publication Date | 2024-03-29 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2452-2236 | ISBN | Additional Links | ||
Impact Factor | 9.3 | Times cited | Open Access | ||
Notes | The work was supported by the Fund for Scientific Research (FWO) Flanders Bioeconomy project (grant G0G2322N) funded by the European Union-NextGe- nerationEU, the HyPACT project funded by the Belgian Energy Transition Fund, and the MSCA4Ukraine project 1233629 funded by the European Union. | Approved | Most recent IF: 9.3; 2024 IF: NA | ||
Call Number | PLASMANT @ plasmant @ | Serial | 9117 | ||
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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. | ||||
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 |
Volume | Issue | Pages | |||
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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Wos | 001206226700001 | Publication Date | 2024-04-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0935-9648 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 29.4 | Times cited | Open Access | ||
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 | ||
Call Number | EMAT @ emat @c:irua:205967 | Serial | 9118 | ||
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Author | Esteban, D.A.; Chamocho, E.G.; Carretero González, J.; Urones Garrote, E.; Otero Díaz, L.C.; Brande, D.Á. | ||||
Title | Enhancing Electrochemical Properties of Walnut Shell Activated Carbon with Embedded MnO Clusters for Supercapacitor Applications | Type | A1 Journal Article | ||
Year | 2024 | Publication | Batteries & Supercaps | Abbreviated Journal | Batteries & Supercaps |
Volume | Issue | Pages | |||
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | Activated carbon (AC) materials from renewable sources are widely used in electrochemical applications due to their well‐known high surface area. However, their application as electrode material in double‐layer electrochemical devices may be limited due to their relatively low electrical conductivity and lightweight. To overcome these limitations, the incorporation of pseudocapacitance metal oxide nanoparticles is an optimum approach. These nanoparticles can provide a second energy storage mechanism to the composite, mitigating the loss of surface area associated with their incorporation. As a result, the composite material is endowed with increased conductivity and higher density, making it more suitable for practical implementation in real devices. In this study, we have incorporated a fine dispersion of 1 % of MnO clusters into a highly porous activated carbon synthesized from walnut shells (WAC). The high‐resolution electron microscopy studies, combined with their related analytical techniques, allow us to determine the presence of the cluster within the matrix carbon precisely. The resulting MnO@WAC composite demonstrated significantly improved capacitive behavior compared with the WAC material, with increased volumetric capacitance and higher charge retention at higher current densities. The composite‘s electrochemical performance suggests its potential as a promising electrode material for supercapacitors, addressing drawbacks associated with traditional AC materials. | ||||
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Wos | 001198179300001 | Publication Date | 2024-04-08 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2566-6223 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | Times cited | Open Access | |||
Notes | Grants PID2020-112848RB-C21 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union PRTR funding through projects are acknowledged. Access to the ICTS- CNME for TEM is also acknowledged. | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @c:irua:205463 | Serial | 9119 | ||
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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. | ||||
Title | Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures | Type | A1 Journal Article | ||
Year | 2024 | Publication | APL Materials | Abbreviated Journal | |
Volume | 12 | Issue | 4 | Pages | |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
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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Wos | 001202661800003 | Publication Date | 2024-04-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2166-532X | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 6.1 | Times cited | Open Access | ||
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 | ||
Call Number | EMAT @ emat @c:irua:205569 | Serial | 9120 | ||
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Author | Vlasov, E.; Heyvaert, W.; Ni, B.; Van Gordon, K.; Girod, R.; Verbeeck, J.; Liz-Marzán, L.M.; Bals, S. | ||||
Title | High-Throughput Morphological Chirality Quantification of Twisted and Wrinkled Gold Nanorods | Type | A1 Journal Article | ||
Year | 2024 | Publication | ACS Nano | Abbreviated Journal | ACS Nano |
Volume | Issue | Pages | |||
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | Chirality in gold nanostructures offers an exciting opportunity to tune their differential optical response to left- and right-handed circularly polarized light, as well as their interactions with biomolecules and living matter. However, tuning and understanding such interactions demands quantification of the structural features that are responsible for the chiral behavior. Electron tomography (ET) enables structural characterization at the single-particle level and has been used to quantify the helicity of complex chiral nanorods. However, the technique is time-consuming and consequently lacks statistical value. To address this issue, we introduce herein a high-throughput methodology that combines images acquired by secondary electron-based electron beam-induced current (SEEBIC) with quantitative image analysis. As a result, the geometric chirality of hundreds of nanoparticles can be quantified in less than 1 h. When combining the drastic gain in data collection efficiency of SEEBIC with a limited number of ET data sets, a better understanding of how the chiral structure of individual chiral nanoparticles translates into the ensemble chiroptical response can be reached. | ||||
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Wos | Publication Date | 2024-04-26 | ||
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ISSN | 1936-0851 | ISBN | Additional Links | ||
Impact Factor | 17.1 | Times cited | Open Access | ||
Notes | The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.) and from MCIN/AEI/10.13039/501100011033 (Grant PID2020-117779RB-I00 to L.M.L.-M and FPI Fellowship PRE2021-097588 to K.V.G.). Funded by the European Union under Project 101131111 − DELIGHT, JV acknowledges the eBEAM project supported by the European Union’s Horizon 2020 research and innovation program FETPROACT-EIC-07- 2020: emerging paradigms and communities. | Approved | Most recent IF: 17.1; 2024 IF: 13.942 | ||
Call Number | EMAT @ emat @ | Serial | 9121 | ||
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Author | Zhou, R.; Neek-Amal, M.; Peeters, F.M.; Bai, B.; Sun, C. | ||||
Title | Interlink between Abnormal Water Imbibition in Hydrophilic and Rapid Flow in Hydrophobic Nanochannels | Type | A1 Journal Article | ||
Year | 2024 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
Volume | 132 | Issue | 18 | Pages | 184001 |
Keywords | A1 Journal Article; CMT | ||||
Abstract | Nanoscale extension and refinement of the Lucas-Washburn model is presented with a detailed analysis of recent experimental data and extensive molecular dynamics simulations to investigate rapid water flow and water imbibition within nanocapillaries. Through a comparative analysis of capillary rise in hydrophilic nanochannels, an unexpected reversal of the anticipated trend, with an abnormal peak, of imbibition length below the size of 3 nm was discovered in hydrophilic nanochannels, surprisingly sharing the same physical origin as the well-known peak observed in flow rate within hydrophobic nanochannels. The extended imbibition model is applicable across diverse spatiotemporal scales and validated against simulation results and existing experimental data for both hydrophilic and hydrophobic | ||||
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Wos | Publication Date | 2024-04-30 | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007 | ISBN | Additional Links | ||
Impact Factor | 8.6 | Times cited | 1 | Open Access | |
Notes | We gratefully acknowledge the financial support pro- vided by the National Natural Science Foundation of China (Projects No. 52488201 and No. 52222606). Part of this project was supported by the Flemish Science Foundations (FWO-Vl) and the Iranian National Science Foundation (No. 4025061 and No. 4021261). | Approved | Most recent IF: 8.6; 2024 IF: 8.462 | ||
Call Number | UA @ lucian @ | Serial | 9122 | ||
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Author | Faraji, F.; Neyts, E.C.; Milošević, M.V.; Peeters, F.M. | ||||
Title | Capillary Condensation of Water in Graphene Nanocapillaries | Type | A1 Journal Article | ||
Year | 2024 | Publication | Nano Letters | Abbreviated Journal | Nano Lett. |
Volume | 24 | Issue | 18 | Pages | 5625-5630 |
Keywords | A1 Journal Article; CMT | ||||
Abstract | Recent experiments have revealed that the macroscopic Kelvin equation remains surprisingly accurate even for nanoscale capillaries. This phenomenon was so far explained by the oscillatory behavior of the solid−liquid interfacial free energy. We here demonstrate thermodynamic and capillarity inconsistencies with this explanation. After revising the Kelvin equation, we ascribe its validity at nanoscale confinement to the effect of disjoining pressure. To substantiate our hypothesis, we employed molecular dynamics simulations to evaluate interfacial heat transfer and wetting properties. Our assessments unveil a breakdown in a previously established proportionality between the work of adhesion and the Kapitza conductance at capillary heights below 1.3 nm, where the dominance of the work of adhesion shifts primarily from energy to entropy. Alternatively, the peak density of the initial water layer can effectively probe the work of adhesion. Unlike under bulk conditions, high confinement renders the work of adhesion entropically unfavorable. |
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Wos | Publication Date | 2024-05-08 | ||
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ISSN | 1530-6984 | ISBN | Additional Links | ||
Impact Factor | 10.8 | Times cited | Open Access | ||
Notes | This work was supported by Research Foundation-Flanders (FWO, project No. G099219N). The computational resources used in this work were provided by the HPC core facility CalcUA of the University of Antwerp, and the Flemish Supercomputer Center (VSC), funded by FWO and the Flemish Government. | Approved | Most recent IF: 10.8; 2024 IF: 12.712 | ||
Call Number | UA @ lucian @ | Serial | 9123 | ||
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Author | Cai, Y.; Mei, D.; Chen, Y.; Bogaerts, A.; Tu, X. | ||||
Title | Machine learning-driven optimization of plasma-catalytic dry reforming of methane | Type | A1 Journal Article | ||
Year | 2024 | Publication | Journal of Energy Chemistry | Abbreviated Journal | Journal of Energy Chemistry |
Volume | 96 | Issue | Pages | 153-163 | |
Keywords | A1 Journal Article; Plasma catalysis Machine learning Process optimization Dry reforming of methane Syngas production; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | This study investigates the dry reformation of methane (DRM) over Ni/Al2O3 catalysts in a dielectric barrier discharge (DBD) non-thermal plasma reactor. A novel hybrid machine learning (ML) model is developed to optimize the plasma-catalytic DRM reaction with limited experimental data. To address the non-linear and complex nature of the plasma-catalytic DRM process, the hybrid ML model integrates three well-established algorithms: regression trees, support vector regression, and artificial neural networks. A genetic algorithm (GA) is then used to optimize the hyperparameters of each algorithm within the hybrid ML model. The ML model achieved excellent agreement with the experimental data, demonstrating its efficacy in accurately predicting and optimizing the DRM process. The model was subsequently used to investigate the impact of various operating parameters on the plasma-catalytic DRM performance. We found that the optimal discharge power (20 W), CO2/CH4 molar ratio (1.5), and Ni loading (7.8 wt%) resulted in the maximum energy yield at a total flow rate of 51 mL/min. Furthermore, we investigated the relative significance of each operating parameter on the performance of the plasmacatalytic DRM process. The results show that the total flow rate had the greatest influence on the conversion, with a significance exceeding 35% for each output, while the Ni loading had the least impact on the overall reaction performance. This hybrid model demonstrates a remarkable ability to extract valuable insights from limited datasets, enabling the development and optimization of more efficient and selective plasma-catalytic chemical processes. | ||||
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Wos | Publication Date | 2024-04-25 | ||
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ISSN | 2095-4956 | ISBN | Additional Links | ||
Impact Factor | 13.1 | Times cited | Open Access | ||
Notes | This project received funding from the European Union’s Hori- zon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 813393. | Approved | Most recent IF: 13.1; 2024 IF: 2.594 | ||
Call Number | PLASMANT @ plasmant @ | Serial | 9124 | ||
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Author | Albrechts, M.; Tsonev, I.; Bogaerts, A. | ||||
Title | Investigation of O atom kinetics in O2plasma and its afterglow | Type | A1 Journal Article | ||
Year | 2024 | Publication | Plasma Sources Science and Technology | Abbreviated Journal | Plasma Sources Sci. Technol. |
Volume | 33 | Issue | 4 | Pages | 045017 |
Keywords | A1 Journal Article; oxygen plasma, pseudo-1D plug-flow kinetic model, O atoms, low-pressure validation, atmospheric pressure microwave torch; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | We have developed a comprehensive kinetic model to study the O atom kinetics in an O<sub>2</sub>plasma and its afterglow. By adopting a pseudo-1D plug-flow formalism within the kinetic model, our aim is to assess how far the O atoms travel in the plasma afterglow, evaluating its potential as a source of O atoms for post-plasma gas conversion applications. Since we could not find experimental data for pure O<sub>2</sub>plasma at atmospheric pressure, we first validated our model at low pressure (1–10 Torr) where very good experimental data are available. Good agreement between our model and experiments was achieved for the reduced electric field, gas temperature and the densities of the dominant neutral species, i.e. O<sub>2</sub>(a), O<sub>2</sub>(b) and O. Subsequently, we confirmed that the chemistry set is consistent with thermodynamic equilibrium calculations at atmospheric pressure. Finally, we investigated the O atom densities in the O<sub>2</sub>plasma and its afterglow, for which we considered a microwave O<sub>2</sub>plasma torch, operating at a pressure between 0.1 and 1 atm, for a flow rate of 20 slm and an specific energy input of 1656 kJ mol<sup>−1</sup>. Our results show that for both pressure conditions, a high dissociation degree of ca. 92% is reached within the discharge. However, the O atoms travel much further in the plasma afterglow for<italic>p</italic>= 0.1 atm (9.7 cm) than for<italic>p</italic>= 1 atm (1.4 cm), attributed to the longer lifetime (3.8 ms at 0.1 atm vs 1.8 ms at 1 atm) resulting from slower three-body recombination kinetics, as well as a higher volumetric flow rate. | ||||
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Wos | 001209453500001 | Publication Date | 2024-04-01 | |
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ISSN | 0963-0252 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.8 | Times cited | Open Access | ||
Notes | This research was supported by the Horizon Europe Framework Program ‘Research and Innovation Actions’ (RIA), Project CANMILK (Grant No. 101069491). | Approved | Most recent IF: 3.8; 2024 IF: 3.302 | ||
Call Number | PLASMANT @ plasmant @c:irua:205920 | Serial | 9125 | ||
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Author | Guerrero, R.M.; Lemir, I.D.; Carrasco, S.; Fernández-Ruiz, C.; Kavak, S.; Pizarro, P.; Serrano, D.P.; Bals, S.; Horcajada, P.; Pérez, Y. | ||||
Title | Scaling-Up Microwave-Assisted Synthesis of Highly Defective Pd@UiO-66-NH2Catalysts for Selective Olefin Hydrogenation under Ambient Conditions | Type | A1 Journal Article | ||
Year | 2024 | Publication | ACS Applied Materials & Interfaces | Abbreviated Journal | ACS Appl. Mater. Interfaces |
Volume | Issue | Pages | |||
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | The need to develop green and cost-effective industrial catalytic processes has led to growing interest in preparing more robust, efficient, and selective heterogeneous catalysts at a large scale. In this regard, microwave-assisted synthesis is a fast method for fabricating heterogeneous catalysts (including metal oxides, zeolites, metal–organic frameworks, and supported metal nanoparticles) with enhanced catalytic properties, enabling synthesis scale-up. Herein, the synthesis of nanosized UiO-66-NH2 was optimized via a microwave-assisted hydrothermal method to obtain defective matrices essential for the stabilization of metal nanoparticles, promoting catalytically active sites for hydrogenation reactions (760 kg·m–3·day–1 space time yield, STY). Then, this protocol was scaled up in a multimodal microwave reactor, reaching 86% yield (ca. 1 g, 1450 kg·m–3·day–1 STY) in only 30 min. Afterward, Pd nanoparticles were formed in situ decorating the nanoMOF by an effective and fast microwave-assisted hydrothermal method, resulting in the formation of Pd@UiO-66-NH2 composites. Both the localization and oxidation states of Pd nanoparticles (NPs) in the MOF were achieved using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray photoelectron spectroscopy (XPS), respectively. The optimal composite, loaded with 1.7 wt % Pd, exhibited an extraordinary catalytic activity (>95% yield, 100% selectivity) under mild conditions (1 bar H2, 25 °C, 1 h reaction time), not only in the selective hydrogenation of a variety of single alkenes (1-hexene, 1-octene, 1-tridecene, cyclohexene, and tetraphenyl ethylene) but also in the conversion of a complex mixture of alkenes (i.e., 1-hexene, 1-tridecene, and anethole). The results showed a powerful interaction and synergy between the active phase (Pd NPs) and the catalytic porous scaffold (UiO-66-NH2), which are essential for the selectivity and recyclability. | ||||
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Wos | Publication Date | 2024-04-26 | ||
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ISSN | 1944-8244 | ISBN | Additional Links | ||
Impact Factor | 9.5 | Times cited | Open Access | ||
Notes | The authors gratefully acknowledge financial support from “Comunidad de Madrid” and European Regional Development Fund-FEDER through the project HUB MADRID+CIRCULAR; the State Research Agency (MCIN/AEI /10.13039/501100011033) through the grant with reference number CEX2019-000931-M received in the 2019 call for “Severo Ochoa Centres of Excellence” and “María de Maeztu Units of Excellence” of the State Programme for Knowledge Generation and Scientific and Technological Strengthening of the R&D&I System; and MICIU through the project “NAPOLION” (PID2022-139956OB-I00). S.K. acknowledges the Flemish Fund for Scientific Research (FWO Vlaanderen) through a PhD research grant (1181124N). | Approved | Most recent IF: 9.5; 2024 IF: 7.504 | ||
Call Number | EMAT @ emat @ | Serial | 9126 | ||
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Author | Leinders, G.; Grendal, O.G.; Arts, I.; Bes, R.; Prozheev, I.; Orlat, S.; Fitch, A.; Kvashnina, K.; Verwerft, M. | ||||
Title | Refinement of the uranium dispersion corrections from anomalous diffraction | Type | A1 Journal Article | ||
Year | 2024 | Publication | Journal of Applied Crystallography | Abbreviated Journal | J Appl Cryst |
Volume | 57 | Issue | 2 | Pages | 284-295 |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | The evolution of the uranium chemical state in uranium compounds, principally in the oxides, is of concern in the context of nuclear fuel degradation under storage and repository conditions, and in accident scenarios. The U–O system shows complicated phase relations between single-valence uranium dioxide (UO<sub>2</sub>) and different mixed-valence compounds (<italic>e.g.</italic>U<sub>4</sub>O<sub>9</sub>, U<sub>3</sub>O<sub>7</sub>and U<sub>3</sub>O<sub>8</sub>). To try resolving the electronic structure associated with unique atomic positions, a combined application of diffraction and spectroscopic techniques, such as diffraction anomalous fine structure (DAFS), can be considered. Reported here is the application of two newly developed routines for assessing a DAFS data set, with the aim of refining the uranium X-ray dispersion corrections. High-resolution anomalous diffraction data were acquired from polycrystalline powder samples of UO<sub>2</sub>(containing tetravalent uranium) and potassium uranate (KUO<sub>3</sub>, containing pentavalent uranium) using synchrotron radiation in the vicinity of the U<italic>L</italic><sub>3</sub>edge (17.17 keV). Both routines are based on an iterative refinement of the dispersion corrections, but they differ in either using the intensity of a selection of reflections or doing a full-pattern (Rietveld method) refinement. The uranium dispersion corrections obtained using either method are in excellent agreement with each other, and they show in great detail the chemical shifts and differences in fine structure expected for tetravalent and pentavalent uranium. This approach may open new possibilities for the assessment of other, more complicated, materials such as mixed-valence compounds. Additionally, the DAFS methodology can offer a significant resource optimization because each data set contains both structural (diffraction) and chemical (spectroscopy) information, which can avoid the requirement to use multiple experimental stations at synchrotron sources. | ||||
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Wos | 001208800100008 | Publication Date | 2024-04-01 | |
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ISSN | 1600-5767 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 6.1 | Times cited | Open Access | ||
Notes | FPS Economy, SF-CORMOD; | Approved | Most recent IF: 6.1; 2024 IF: 2.495 | ||
Call Number | EMAT @ emat @c:irua:206011 | Serial | 9127 | ||
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