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Author Neyts, E.C.; Ostrikov, K.K.; Sunkara, M.K.; Bogaerts, A.
Title Plasma Catalysis: Synergistic Effects at the Nanoscale Type A1 Journal article
Year 2015 Publication Chemical reviews Abbreviated Journal Chem Rev
Volume 115 Issue 115 Pages 13408-13446
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Thermal-catalytic gas processing is integral to many current industrial processes. Ever-increasing demands on conversion and energy efficiencies are a strong driving force for the development of alternative approaches. Similarly, synthesis of several functional materials (such as nanowires and nanotubes) demands special processing conditions. Plasma catalysis provides such an alternative, where the catalytic process is complemented by the use of plasmas that activate the source gas. This combination is often observed to result in a synergy between plasma and catalyst. This Review introduces the current state-of-the-art in plasma catalysis, including numerous examples where plasma catalysis has demonstrated its benefits or shows future potential, including CO2 conversion, hydrocarbon reforming, synthesis of nanomaterials, ammonia production, and abatement of toxic waste gases. The underlying mechanisms governing these applications, as resulting from the interaction between the plasma and the catalyst, render the process highly complex, and little is known about the factors leading to the often-observed synergy. This Review critically examines the catalytic mechanisms relevant to each specific application.
Address Department of Chemistry, Research Group PLASMANT, Universiteit Antwerpen , Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000367563000006 Publication Date 2015-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2665 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 47.928 Times cited 204 Open Access
Notes ECN and AB gratefully acknowledge financial support from the Fund of Scientific Research Flanders (FWO), Belgium, Grant Number G.0217.14N. KO acknowledges partial support by the Australian Research Council and CSIRO’s OCE Science Leaders Program. MKS acknowledges partial support from US National Science Foundation through grants DMS 1125909 and EPSCoR 1355448 and also PhD students Babajide Ajayi, Apolo Nambo and Maria Carreon for their help. Approved Most recent IF: 47.928; 2015 IF: 46.568
Call Number c:irua:130001 Serial 3993
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Author Snoeckx, R.; Bogaerts, A.
Title Plasma technology – a novel solution for CO2conversion? Type A1 Journal article
Year 2017 Publication Chemical Society reviews Abbreviated Journal Chem Soc Rev
Volume 46 Issue 19 Pages 5805-5863
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract CO2 conversion into value-added chemicals and fuels is considered as one of the great challenges of the 21st century. Due to the limitations of the traditional thermal approaches, several novel technologies are being developed. One promising approach in this field, which has received little attention to date, is plasma

technology. Its advantages include mild operating conditions, easy upscaling, and gas activation by energetic electrons instead of heat. This allows thermodynamically difficult reactions, such as CO2 splitting and the dry reformation of methane, to occur with reasonable energy cost. In this review, after exploring the traditional thermal approaches, we have provided a brief overview of the fierce competition between various novel approaches in a quest to find the most effective and efficient CO2 conversion technology. This is needed to critically assess whether plasma technology can be successful in an already crowded arena. The following questions need to be answered in this regard: are there key advantages to using plasma technology over other novel approaches, and if so, what is the flip side to the use of this technology? Can plasma technology be successful on its own, or can synergies be achieved by combining it with other technologies? To answer

these specific questions and to evaluate the potentials and limitations of plasma technology in general, this review presents the current state-of-the-art and a critical assessment of plasma-based CO2 conversion, as well as the future challenges for its practical implementation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000412141600006 Publication Date 2017-08-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0306-0012 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 38.618 Times cited 168 Open Access OpenAccess
Notes We would like to thank W. Wang (University of Antwerp) for providing the data on the thermal equilibrium conversions. Furthermore, we acknowledge financial support from the IAP/7 (Inter-university Attraction Pole) programme ‘PSI-Physical Chemistry of Plasma-Surface Interactions’ by the Belgian Federal Office for Science Policy (BELSPO), the Methusalem financing of the University of Antwerp, the Fund for Scientific Research Flanders (FWO; Grant no. G.0383.16N, G.0254.14N and G.0217.14N), the TOP research project of the Research Fund of the University of Antwerp (grant ID. 32249). Approved Most recent IF: 38.618
Call Number PLASMANT @ plasmant @c:irua:145921 Serial 4709
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Author Ovsyannikov, S.V.; Bykov, M.; Bykova, E.; Kozlenko, D.P.; Tsirlin, A.A.; Karkin, A.E.; Shchennikov, V.V.; Kichanov, S.E.; Gou, H.; Abakumov, A.M.; Egoavil, R.; Verbeeck, J.; McCammon, C.; Dyadkin, V.; Chernyshov, D.; van Smaalen, S.; Dubrovinsky, L.S.
Title Charge-ordering transition in iron oxide Fe4O5 involving competing dimer and trimer formation Type A1 Journal article
Year 2016 Publication Nature chemistry Abbreviated Journal Nat Chem
Volume 8 Issue 8 Pages 501-508
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Phase transitions that occur in materials, driven, for instance, by changes in temperature or pressure, can dramatically change the materials' properties. Discovering new types of transitions and understanding their mechanisms is important not only from a fundamental perspective, but also for practical applications. Here we investigate a recently discovered Fe4O5 that adopts an orthorhombic CaFe3O5-type crystal structure that features linear chains of Fe ions. On cooling below approximately 150 K, Fe4O5 undergoes an unusual charge-ordering transition that involves competing dimeric and trimeric ordering within the chains of Fe ions. This transition is concurrent with a significant increase in electrical resistivity. Magnetic-susceptibility measurements and neutron diffraction establish the formation of a collinear antiferromagnetic order above room temperature and a spin canting at 85 K that gives rise to spontaneous magnetization. We discuss possible mechanisms of this transition and compare it with the trimeronic charge ordering observed in magnetite below the Verwey transition temperature.
Address Bayerisches Geoinstitut, Universitat Bayreuth, Universitatsstrasse 30, D-95447, Bayreuth, Germany
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000374534100019 Publication Date 2016-04-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1755-4330 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 25.87 Times cited 51 Open Access
Notes S.V.O. acknowledges the financial support of the Deutsche Forschungsgemeinschaft (DFG) under project OV-110/1-3. A.E.K. and V.V.S. acknowledge the support of the Russian Foundation for Basic Research (Project 14–02–00622a). H.G. acknowledges the support from the Alexander von Humboldt (AvH) Foundation and the National Natural Science Foundation of China (No. 51201148). A.M.A., R.E. and J.V. acknowledge financial support from the European Commission (EC) under the Seventh Framework Programme (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483- ESTEEM2. R.E. acknowledges support from the EC under FP7 Grant No. 246102 IFOX. A.M.A. acknowledges funding from the Russian Science Foundation (Grant No. 14-13- 00680). A.A.T. acknowledges funding and from the Federal Ministry for Education and Research through the Sofja Kovalevkaya Award of the AvH Foundation. Funding from the Fund for Scientific Research Flanders under FWO Project G.0044.13N is acknowledged. M.B. and S.v.S. acknowledge support from the DFG under Project Sm55/15-2. We acknowledge the European Synchrotron Radiation Facility for the provision of synchrotron radiation facilities.; esteem2jra2; esteem2jra3 Approved Most recent IF: 25.87
Call Number c:irua:133593 c:irua:133593UA @ admin @ c:irua:133593 Serial 4068
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Author O'Sullivan, M.; Hadermann, J.; Dyer, M.S.; Turner, S.; Alaria, J.; Manning, T.D.; Abakumov, A.M.; Claridge, J.B.; Rosseinsky, M.J.
Title Interface control by chemical and dimensional matching in an oxide heterostructure Type A1 Journal article
Year 2016 Publication Nature chemistry Abbreviated Journal Nat Chem
Volume 8 Issue 8 Pages 347-353
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Interfaces between different materials underpin both new scientific phenomena, such as the emergent behaviour at oxide interfaces, and key technologies, such as that of the transistor. Control of the interfaces between materials with the same crystal structures but different chemical compositions is possible in many materials classes, but less progress has been made for oxide materials with different crystal structures. We show that dynamical self-organization during growth can create a coherent interface between the perovskite and fluorite oxide structures, which are based on different structural motifs, if an appropriate choice of cations is made to enable this restructuring. The integration of calculation with experimental observation reveals that the interface differs from both the bulk components and identifies the chemical bonding requirements to connect distinct oxide structures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000372505500013 Publication Date 2016-02-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1755-4330; 1755-4349 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 25.87 Times cited 28 Open Access
Notes Approved Most recent IF: 25.87
Call Number UA @ lucian @ c:irua:133189 Serial 4199
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Author Zhou, Y.; Che, F.; Liu, M.; Zou, C.; Liang, Z.; De Luna, P.; Yuan, H.; Li, J.; Wang, Z.; Xie, H.; Li, H.; Chen, P.; Bladt, E.; Quintero-Bermudez, R.; Sham, T.-K.; Bals, S.; Hofkens, J.; Sinton, D.; Chen, G.; Sargent, E.H.
Title Dopant-induced electron localization drives CO2 reduction to C2 hydrocarbons Type A1 Journal article
Year 2018 Publication Nature chemistry Abbreviated Journal Nat Chem
Volume 10 Issue 10 Pages 974-980
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The electrochemical reduction of CO2 to multi-carbon products has attracted much attention because it provides an avenue to the synthesis of value-added carbon-based fuels and feedstocks using renewable electricity. Unfortunately, the efficiency of CO2 conversion to C-2 products remains below that necessary for its implementation at scale. Modifying the local electronic structure of copper with positive valence sites has been predicted to boost conversion to C-2 products. Here, we use boron to tune the ratio of Cu delta+ to Cu-0 active sites and improve both stability and C-2-product generation. Simulations show that the ability to tune the average oxidation state of copper enables control over CO adsorption and dimerization, and makes it possible to implement a preference for the electrosynthesis of C-2 products. We report experimentally a C-2 Faradaic efficiency of 79 +/- 2% on boron-doped copper catalysts and further show that boron doping leads to catalysts that are stable for in excess of similar to 40 hours while electrochemically reducing CO2 to multi-carbon hydrocarbons.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000442395200013 Publication Date 2018-07-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1755-4330; 1755-4349 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 25.87 Times cited 700 Open Access OpenAccess
Notes ; This work was supported financially by funding from TOTAL S.A., the Ontario Research Fund: Research Excellence Program, the Natural Sciences and Engineering Research Council of Canada, the CIFAR Bio-Inspired Solar Energy programme, a University of Toronto Connaught grant, the Ministry of Science, Natural Science Foundation of China (21471040, 21271055 and 21501035), the Innovation-Driven Plan in Central South University project (2017CX003), a project from State Key Laboratory of Powder Metallurgy in Central South University, the Thousand Youth Talents Plan of China and Hundred Youth Talents Program of Hunan and the China Scholarship Council programme. This work benefited from the soft X-ray microcharacterization beamline at CLS, sector 20BM at the APS and the Ontario Centre for the Characterisation of Advanced Materials at the University of Toronto. H.Y. acknowledges financial support from the Research Foundation-Flanders (FWO postdoctoral fellowship). C.Z. acknowledges support from the International Academic Exchange Fund for Joint PhD Students from Tianjin University. P.D.L. acknowledges financial support from the Natural Sciences and Engineering Research Council in the form of the Canada Graduate Scholarship-Doctoral award. S.B. and E.B. acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). The authors thank B. Zhang, N. Wang, C. T. Dinh, T. Zhuang, J. Li and Y. Zhao for fruitful discussions, as well as Y. Hu and Q. Xiao from CLS, and Z. Finfrock and M. Ward from APS for their help during the course of study. Computations were performed on the SOSCIP Consortium's Blue Gene/Q computing platform. SOSCIP is funded by the Federal Economic Development Agency of Southern Ontario, the Province of Ontario, IBM Canada, Ontario Centres of Excellence, Mitacs and 15 Ontario academic member institutions. ; ecas_sara Approved Most recent IF: 25.87
Call Number UA @ lucian @ c:irua:153693UA @ admin @ c:irua:153693 Serial 5091
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Author Kelly, S.; Verheyen, C.; Cowley, A.; Bogaerts, A.
Title Producing oxygen and fertilizer with the Martian atmosphere by using microwave plasma Type A1 Journal article
Year 2022 Publication Chem Abbreviated Journal Chem
Volume 8 Issue 10 Pages 2797-2816
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We explorethepotentialofmicrowave(MW)-plasma-based in situ

utilizationoftheMartianatmospherewithafocusonthenovelpos-

sibilityoffixingN2 forfertilizerproduction. Conversioninasimulant

plasma (i.e., 96% CO2, 2% N2, and 2% Ar),performedunderen-

ergyconditionssimilartothoseoftheMarsOxygen In Situ Resource

UtilizationExperiment(MOXIE),currentlyonboardNASA’sPerse-

verancerover,demonstratesthatO/O2 formedthroughCO2 dissociation

facilitatesthefixationoftheN2 fractionviaoxidationtoNOx.

PromisingproductionratesforO2, CO,andNOx of 47.0,76.1,and

1.25g/h,respectively,arerecordedwithcorrespondingenergy

costs of0.021,0.013,and0.79kWh/g,respectively.Notably,O2

productionratesare 30 timeshigherthanthosedemonstrated

by MOXIE,whiletheNOx production raterepresentsan 7% fixa-

tionoftheN2 fraction presentintheMartian atmosphere.MW-

plasma-basedconversionthereforeshowsgreatpotentialasan in

situ resourceutilization(ISRU)technologyonMarsinthatitsimulta-

neouslyfixesN2 and producesO2.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000875346600005 Publication Date 2022-08-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2451-9294 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 23.5 Times cited Open Access OpenAccess
Notes the Euro- pean 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), and the Excellence of Science FWO-FNRS project (FWO grant no. GoF9618n and EOS no. 30505023). C.V. was supported by a FWO aspirant PhD fellowship (grant no. 1184820N). The calculations were per- formed with the Turing HPC infrastructure at the CalcUA core facility of the Univer- siteit Antwerpen (Uantwerpen), a division of the Flemish Supercomputer Centre VSC, funded by the Hercules Foundation, the Flemish government (department EWI), and Uantwerpen. Approved Most recent IF: 23.5
Call Number PLASMANT @ plasmant @c:irua:192174 Serial 7243
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Author Khalilov, U.; Bogaerts, A.; Neyts, E.C.
Title Toward the Understanding of Selective Si Nano-Oxidation by Atomic Scale Simulations Type A1 Journal article
Year 2017 Publication Accounts of chemical research Abbreviated Journal Accounts Chem Res
Volume 50 Issue 50 Pages 796-804
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The continuous miniaturization of nanodevices, such as transistors, solar cells, and optical fibers, requires the controlled synthesis of (ultra)thin gate oxides (<10 nm), including Si gate-oxide (SiO2) with high quality at the atomic scale. Traditional thermal growth of SiO2 on planar Si surfaces, however, does not allow one to obtain such ultrathin oxide due to either the high oxygen diffusivity at high temperature or the very low sticking ability of incident oxygen at low temperature. Two recent techniques, both operative at low (room) temperature, have been put forward to overcome these obstacles: (i) hyperthermal oxidation of planar Si surfaces and (ii) thermal or plasma-assisted oxidation of nonplanar Si surfaces, including Si nanowires (SiNWs). These nanooxidation processes are, however, often difficult to study experimentally, due to the key intermediate processes taking place on the nanosecond time scale.

In this Account, these Si nano-oxidation techniques are discussed from a computational point of view and compared to both hyperthermal and thermal oxidation experiments, as well as to well-known models of thermal oxidation, including the Deal−Grove, Cabrera−Mott, and Kao models and several alternative mechanisms. In our studies, we use reactive molecular dynamics (MD) and hybrid MD/Monte Carlo simulation techniques, applying the Reax force field. The incident energy of oxygen species is chosen in the range of 1−5 eV in hyperthermal oxidation of planar Si surfaces in order to prevent energy-induced damage. It turns out that hyperthermal growth allows for two growth modes, where the ultrathin oxide thickness depends on either (1) only the kinetic energy of the incident oxygen species at a growth temperature below Ttrans = 600 K, or (2) both the incident energy and the growth temperature at a growth temperature above Ttrans. These modes are specific to such ultrathin oxides, and are not observed in traditional thermal oxidation, nor theoretically considered by already existing models. In the case of thermal or plasma-assisted oxidation of small Si nanowires, on the other hand, the thickness of the ultrathin oxide is a function of the growth temperature and the nanowire diameter. Below Ttrans, which varies with the nanowire diameter, partially oxidized SiNW are formed, whereas complete oxidation to a SiO2 nanowire occurs only above Ttrans. In both nano-oxidation processes at lower temperature (T < Ttrans), final sandwich c-Si|SiOx|a-SiO2 structures are obtained due to a competition between overcoming the energy barrier to penetrate into Si subsurface layers and the compressive stress (∼2−3 GPa) at the Si crystal/oxide interface. The overall atomic-simulation results strongly indicate that the thickness of the intermediate SiOx (x < 2) region is very limited (∼0.5 nm) and constant irrespective of oxidation parameters. Thus, control over the ultrathin SiO2 thickness with good quality is indeed possible by accurately tuning the oxidant energy, oxidation temperature and surface curvature.

In general, we discuss and put in perspective these two oxidation mechanisms for obtaining controllable ultrathin gate-oxide films, offering a new route toward the fabrication of nanodevices via selective nano-oxidation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000399859800016 Publication Date 2017-04-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0001-4842 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 20.268 Times cited 5 Open Access OpenAccess
Notes Fonds Wetenschappelijk Onderzoek, 12M1315N ; Approved Most recent IF: 20.268
Call Number PLASMANT @ plasmant @ c:irua:142638 Serial 4561
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Author Janssens, K.; Dik, J.; Cotte, M.; Susini, J.
Title Photon-based techniques for nondestructive subsurface analysis of painted cultural heritage artifacts Type A1 Journal article
Year 2010 Publication Accounts of chemical research Abbreviated Journal Accounts Chem Res
Volume 43 Issue 6 Pages 814-825
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Often, just micrometers below a paintings surface lies a wealth of information, both with Old Masters such as Peter Paul Rubens and Rembrandt van Rijn and with more recent artists of great renown such as Vincent Van Gogh and James Ensor. Subsurface layers may include underdrawing, underpainting, and alterations, and in a growing number of cases conservators have discovered abandoned compositions on paintings, illustrating artists practice of reusing a canvas or panel. The standard methods for studying the inner structure of cultural heritage (CH) artifacts are infrared reflectography and X-ray radiography, techniques that are optionally complemented with the microscopic analysis of cross-sectioned samples. These methods have limitations, but recently, a number of fundamentally new approaches for fully imaging the buildup of hidden paint layers and other complex three-dimensional (3D) substructures have been put into practice. In this Account, we discuss these developments and their recent practical application with CH artifacts. We begin with a tabular summary of 14 IR- and X-ray-based imaging methods and then continue with a discussion of each technique, illustrating CH applications with specific case studies. X-ray-based tomographic and laminographic techniques can be used to generate 3D renditions of artifacts of varying dimensions. These methods are proving invaluable for exploring inner structures, identifying the conservation state, and postulating the original manufacturing technology of metallic and other sculptures. In the analysis of paint layers, terahertz time-domain spectroscopy (THz-TDS) can highlight interfaces between layers in a stratigraphic buildup, whereas macrosopic scanning X-ray fluorescence (MA-XRF) has been employed to measure the distribution of pigments within these layers. This combination of innovative methods provides topographic and color information about the micrometer depth scale, allowing us to look into paintings in an entirely new manner. Over the past five years, several new variants of traditional IR- and X-ray-based imaging methods have been implemented by conservators and museums, and the first reports have begun to emerge in the primary research literature. Applying these state-of-the-art techniques in a complementary fashion affords a more comprehensive view of paintings and other artworks.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278842500013 Publication Date 2010-05-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0001-4842 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 20.268 Times cited 78 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of FWO (Brussels, Belgium) projects nr. G.0704.08 and G.0179.09 and from the UA-BOF GOA programme. ; Approved Most recent IF: 20.268; 2010 IF: 21.852
Call Number UA @ admin @ c:irua:83983 Serial 5772
Permanent link to this record
 
 
Author Cotte, M.; Susini, J.; Dik, J.; Janssens, K.
Title Synchrotron-based X-ray absorption spectroscopy for art conservation: looking back and looking forward Type A1 Journal article
Year 2010 Publication Accounts of chemical research Abbreviated Journal Accounts Chem Res
Volume 43 Issue 6 Pages 705-714
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract A variety of analytical techniques augmented by the use of synchrotron radiation (SR), such as X-ray fluorescence (SR-XRF) and X-ray diffraction (SR-XRD), are now readily available, and they differ little, conceptually, from their common laboratory counterparts. Because of numerous advantages afforded by SR-based techniques over benchtop versions, however, SR methods have become popular with archaeologists, art historians, curators, and other researchers in the field of cultural heritage (CH). Although the CH community now commonly uses both SR-XRF and SR-XRD, the use of synchrotron-based X-ray absorption spectroscopy (SR-XAS) techniques remains marginal, mostly because CH specialists rarely interact with SR physicists. In this Account, we examine the basic principles and capabilities of XAS techniques in art preservation. XAS techniques offer a combination of features particularly well-suited for the chemical analysis of works of art. The methods are noninvasive, have low detection limits, afford high lateral resolution, and provide exceptional chemical sensitivity. These characteristics are highly desirable for the chemical characterization of precious, heterogeneous, and complex materials. In particular, the chemical mapping capability, with high spatial resolution that provides information about local composition and chemical states, even for trace elements, is a unique asset. The chemistry involved in both the objects history (that is, during fabrication) and future (that is, during preservation and restoration treatments) can be addressed by XAS. On the one hand, many studies seek to explain optical effects occurring in historical glasses or ceramics by probing the molecular environment of relevant chromophores. Hence, XAS can provide insight into craft skills that were mastered years, decades, or centuries ago but were lost over the course of time. On the other hand, XAS can also be used to characterize unwanted reactions, which are then considered alteration phenomena and can dramatically alter the objects original visual properties. In such cases, the bulk elemental composition is usually unchanged. Hence, monitoring oxidation state (or, more generally, other chemical modifications) can be of great importance. Recent applications of XAS in art conservation are reviewed and new trends are discussed, highlighting the value (and future possibilities) of XAS, which remains, given its potential, underutilized in the CH community.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278842500003 Publication Date 2010-01-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0001-4842 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 20.268 Times cited 74 Open Access
Notes ; ; Approved Most recent IF: 20.268; 2010 IF: 21.852
Call Number UA @ admin @ c:irua:83982 Serial 5861
Permanent link to this record
 
 
Author Albrecht, W.; Van Aert, S.; Bals, S.
Title Three-Dimensional Nanoparticle Transformations Captured by an Electron Microscope Type A1 Journal article
Year 2021 Publication Accounts Of Chemical Research Abbreviated Journal Accounts Chem Res
Volume 54 Issue 5 Pages 1189-1199
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000626269900011 Publication Date 2021-03-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0001-4842 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 20.268 Times cited 12 Open Access OpenAccess
Notes The authors acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ERC Consolidator Grants No. 815128–REALNANO and No. 770887–PICOMETRICS), the Research Foundation Flanders (FWO, G.0267.18N), and the European Commission (EUSMI). The authors furthermore acknowledge funding from the European Union’s Horizon 2020 research and innovation program, ESTEEM3. The authors also acknowledge contributions from all co-workers that have contributed over the years: Thomas Altantzis, Annick De Backer, Joost Batenburg and co-workers, Armand Béché, Eva Bladt, Lewys Jones and co-workers, Luis Liz-Marzán and co-workers, Ivan Lobato, Thais Milagres de Oliveira, Peter Nellist and co-workers, Hugo Pérez Garza and co-workers, Alexander Skorikov, Sara Skrabalak and co-workers, Sandra Van Aert, Alfons van Blaaderen and co-workers, Hans Vanrompay, Staf Van Tendeloo, and Johan Verbeeck.; sygmaSB; Approved Most recent IF: 20.268
Call Number EMAT @ emat @c:irua:177644 Serial 6752
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Author Mosquera, J.; Wang, D.; Bals, S.; Liz-Marzan, L.M.
Title Surfactant layers on gold nanorods Type A1 Journal article
Year 2023 Publication Accounts of chemical research Abbreviated Journal
Volume 56 Issue 10 Pages 1204-1212
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Gold nanorods (Au NRs) are an exceptionally promising tool in nanotechnology due to three key factors: (i) their strong interaction with electromagnetic radiation, stemming from their plasmonic nature, (ii) the ease with which the resonance frequency of their longitudinal plasmon mode can be tuned from the visible to the near-infrared region of the electromagnetic spect r u m based on their aspect ratio, and (iii) their simple and cost-effective preparation through seed-mediated chemical growth. In this synthetic method, surfactants play a critical role in controlling the size, shape, and colloidal stabi l i t y of Au NRs. For example, surfactants can stabilize specific crystallographic facets during the formation of Au NRs, leading to t h e formation of NRs with specific morphologies. The process of surfactant adsorption onto the NR surface may result in various assemblies of surfactant molecules, such as spherical micelles, elongated micelles, or bilayers. Again, the assembly mode is critical toward determining the further availabi l i t y of the Au NR surface to the surrounding medium. Despite its importance and a great deal of research effort, the interaction between Au NPs and surfactants remains insufficiently understood, because the assembly process is influenced by numerous factors, including the chemical nature of the surfactant, the surface morphology of Au NPs, and solution parameters. Therefore, gaining a more comprehensive understanding of these interactions is essential to unlock the full potential of the seed-mediated growth method and the applications of plasmonic NPs. A plethora of characterization techniques have been applied to reach such an understanding , but many open questions remain. In this Account, we review the current knowledge on the interactions between surfactants and Au NRs. We briefly introduce the state-of-the-art methods for synthesizing Au NRs and highlight the crucial role of cationic surfactants during this process. The self-assembly and organization of surfactants on the Au NR surface is then discussed to better understand their role in seed-mediated growth. Subsequently, we provide examples and elucidate how chemical additives can be used to modulate micellar assemblies, in turn allowing for a finer control over the growth of Au NRs, including chiral NRs. Next, we review the main experimental characterization and computational modeling techniques that have been applied to shed light on the arrangement of surfactants on Au NRs and summarize the advantages and disadvantages for each technique. The Account ends with a “Conclusions and Outlook” section, outlining promising future research directions and developments that we consider are sti l l required, mostly related to the application of electron microscopy in liquid and in 3D. Finally, we remark on the potential of exploiting machine learning techniques to predict synthetic routes for NPs with predefined structures and properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000986447000001 Publication Date 2023-05-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0001-4842 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 18.3 Times cited 8 Open Access OpenAccess
Notes The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.; ERC AdG No. 787510, 4DbioSERS to L.M.L.-M.) , from MCIN/AEI/10.13039/501100011033 and “ESF Investing in your future” (Grant PID2020-117779RB-I00 to L.M.L.-M. and Grants RYC2019-027842-I , PID2020-117885GA-I00 to J.M.) , and by Guangdong Provincial Key Laboratory of Optical Information Materials and Technology (No. 2017B030301007) , National Center for International Research on Green Optoelectronics (No. 2016B01018) , MOE Interna-tional Laboratory for Optical Information Technologies, and the 111 projects. Approved Most recent IF: 18.3; 2023 IF: 20.268
Call Number UA @ admin @ c:irua:196768 Serial 8940
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Author Smith, J.D.; Bladt, E.; Burkhart, J.A.C.; Winckelmans, N.; Koczkur, K.M.; Ashberry, H.M.; Bals, S.; Skrabalak, S.E.
Title Defect-directed growth of symmetrically branched metal nanocrystals Type A1 Journal article
Year 2020 Publication Angewandte Chemie-International Edition Abbreviated Journal Angew Chem Int Edit
Volume 59 Issue 59 Pages 943-950
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Branched plasmonic nanocrystals (NCs) have attracted much attention due to electric field enhancements at their tips. Seeded growth provides routes to NCs with defined branching patterns and, in turn, near-field distributions with defined symmetries. Here, a systematic analysis was undertaken in which seeds containing different distributions of planar defects were used to grow branched NCs in order to understand how their distributions direct the branching. Characterization of the products by multimode electron tomography and analysis of the NC morphologies at different overgrowth stages indicate that the branching patterns are directed by the seed defects, with the emergence of branches from the seed faces consistent with minimizing volumetric strain energy at the expense of surface energy. These results contrast with growth of branched NCs from single-crystalline seeds and provide a new platform for the synthesis of symmetrically branched plasmonic NCs.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000498760200001 Publication Date 2019-11-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 16.6 Times cited 23 Open Access OpenAccess
Notes ; The authors thank Samantha Harvey for her initial observations of branched structures, Alexander Chen for his help with SAED, the staff of the Nanoscale Characterization Facility (Dr. Yi Yi), Electron Microscopy Center (Dr. David Morgan and Dr. Barry Stein), and Molecular Structure Center at Indiana University. J.S. recognizes a fellowship provided by the Indiana Space Grant Consortium. E.B. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). This project has received funding to S.E.S. from the U.S. National Science Foundation (award numbers: 1602476 and 1904499) and Research Corporation for Scientific Advancement (2017 Frontiers in Research Excellence and Discovery Award) as well as to S.B. from the European Union's Horizon 2020 research and innovation program under grant agreement No 731019 (EUSMI) and No 815128 (REALNANO). ; sygma Approved Most recent IF: 16.6; 2020 IF: 11.994
Call Number UA @ admin @ c:irua:165124 Serial 6293
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Author Paul, S.; Bladt, E.; Richter, A.F.; Döblinger, M.; Tong, Y.; Huang, H.; Dey, A.; Bals, S.; Debnath, T.; Polavarapu, L.; Feldmann, J.
Title Manganese‐Doping‐Induced Quantum Confinement within Host Perovskite Nanocrystals through Ruddlesden–Popper Defects Type A1 Journal article
Year 2020 Publication Angewandte Chemie-International Edition Abbreviated Journal Angew Chem Int Edit
Volume 59 Issue 17 Pages 6794-6799
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The concept of doping Mn2+ ions into II–VI semiconductor nanocrystals (NCs) was recently extended to perovskite NCs. To date, most studies on Mn2+ doped NCs focus on enhancing the emission related to the Mn2+ dopant via an energy transfer mechanism. Herein, we found that the doping of Mn2+ ions into CsPbCl3 NCs not only results in a Mn2+‐related orange emission, but also strongly influences the excitonic properties of the host NCs. We observe for the first time that Mn2+ doping leads to the formation of Ruddlesden–Popper (R.P.) defects and thus induces quantum confinement within the host NCs. We find that a slight doping with Mn2+ ions improves the size distribution of the NCs, which results in a prominent excitonic peak. However, with increasing the Mn2+ concentration, the number of R.P. planes increases leading to smaller single‐crystal domains. The thus enhanced confinement and crystal inhomogeneity cause a gradual blue shift and broadening of the excitonic transition, respectively.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000525279800024 Publication Date 2020-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 16.6 Times cited 64 Open Access OpenAccess
Notes Deutsche Forschungsgemeinschaft, EXC 2089/1-390776260 ; H2020 European Research Council, 815128-REALNANO ; Horizon 2020 Framework Programme, 839042 731019 ; Alexander von Humboldt-Stiftung; We acknowledge financial support by the Bavarian State Ministry of Science, Research, and Arts through the grant “Solar Technologies go Hybrid (SolTech)”, the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germanys Excellence Strategy—EXC 2089/1‐390776260 (“e‐conversion”), the Alexander von Humboldt Foundation (A.D. and T.D.), the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska‐Curie grant agreement No. 839042 (H.H.). E.B. acknowledges a postdoctoral grant 12T2719N from the Research Foundation Flanders (FWO, Belgium). E.B. and S.B. acknowledge the financial support from the European Research Council ERC Consolidator Grants #815128‐REALNANO. L.P. thanks the EU Infrastructure Project EUSMI (European Union's Horizon 2020, grant No 731019). We thank local research center “Center for NanoScience (CeNS)” for providing communicative networking structure. We acknowledge the funding of Nanosystems Initiative Munich (NIM) for color figures.; sygma Approved Most recent IF: 16.6; 2020 IF: 11.994
Call Number EMAT @ emat @c:irua:168535 Serial 6399
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Author Dooley, K.A.; Chieli, A.; Romani, A.; Legrand, S.; Miliani, C.; Janssens, K.; Delaney, J.K.
Title Molecular fluorescence imaging spectroscopy for mapping low concentrations of red lake pigments : Van Gogh's painting The Olive Orchard Type A1 Journal article
Year 2020 Publication Angewandte Chemie-International Edition Abbreviated Journal Angew Chem Int Edit
Volume Issue Pages
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Vincent van Gogh used fugitive red lake pigments that have faded in some paintings. Mapping their distribution is key to understanding how his paintings have changed with time. While red lake pigments can be identified from microsamples, in situ identification and mapping remain challenging. This paper explores the ability of molecular fluorescence imaging spectroscopy to identify and, more importantly, map residual non-degraded red lakes. The high sensitivity of this method enabled identification of the emission spectra of eosin (tetrabromine fluorescein) lake mixed with lead or zinc white at lower concentrations than elemental X-ray fluorescence (XRF) spectroscopy used on account of bromine. The molecular fluorescence mapping of residual eosin and two carmine red lakes in van Gogh's The Olive Orchard is demonstrated and compared with XRF imaging spectroscopy. The red lakes are consistent with the composition of paint tubes known to have been used by van Gogh.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000512477200001 Publication Date 2020-01-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 16.6 Times cited 2 Open Access
Notes ; We thank Damon Conover and Roxanne Radpour for help with the fluorescence self-absorption correction, and Ella Hendricks for discussions about van Gogh~s letters and materials. K.J. and S.L. thank the Research Council of the University of Antwerp for financial support (ID grant 25805 to S.L. and GOA project SolarPaint). Also FWO, Brussels provided financial support (grants G056619N and G054719N). The European research project IPERION-CH, funded by the European Commission, H2020-INFRAIA-2014-2015 (Grant agreement n. 654028) is also acknowledged. ; Approved Most recent IF: 16.6; 2020 IF: 11.994
Call Number UA @ admin @ c:irua:166490 Serial 6563
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Author Hollevoet, L.; Jardali, F.; Gorbanev, Y.; Creel, J.; Bogaerts, A.; Martens, J.A.
Title Towards green ammonia synthesis through plasma-driven nitrogen oxidation and catalytic reduction Type A1 Journal article
Year 2020 Publication Angewandte Chemie-International Edition Abbreviated Journal Angew Chem Int Edit
Volume Issue Pages
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Ammonia is an industrial large-volume chemical, with its main application in fertilizer production. It also attracts increasing attention as a green-energy vector. Over the past century, ammonia production has been dominated by the Haber-Bosch process, in which a mixture of nitrogen and hydrogen gas is converted to ammonia at high temperatures and pressures. Haber-Bosch processes with natural gas as the source of hydrogen are responsible for a significant share of the global CO(2)emissions. Processes involving plasma are currently being investigated as an alternative for decentralized ammonia production powered by renewable energy sources. In this work, we present the PNOCRA process (plasma nitrogen oxidation and catalytic reduction to ammonia), combining plasma-assisted nitrogen oxidation and lean NO(x)trap technology, adopted from diesel-engine exhaust gas aftertreatment technology. PNOCRA achieves an energy requirement of 4.6 MJ mol(-1)NH(3), which is more than four times less than the state-of-the-art plasma-enabled ammonia synthesis from N(2)and H(2)with reasonable yield (>1 %).
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000580489400001 Publication Date 2020-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 16.6 Times cited 1 Open Access
Notes ; We gratefully acknowledge the financial support by the Flemish Government through the Moonshot cSBO project P2C (HBC.2019.0108). J.A.M. and A.B. acknowledge the Flemish Government for long-term structural funding (Methusalem). ; Approved Most recent IF: 16.6; 2020 IF: 11.994
Call Number UA @ admin @ c:irua:173589 Serial 6634
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Author Otero-Martinez, C.; Imran, M.; Schrenker, N.J.; Ye, J.; Ji, K.; Rao, A.; Stranks, S.D.; Hoye, R.L.Z.; Bals, S.; Manna, L.; Perez-Juste, J.; Polavarapu, L.
Title Fast A-site cation cross-exchange at room temperature : single-to double- and triple-cation halide perovskite nanocrystals Type A1 Journal article
Year 2022 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 61 Issue 34 Pages e202205617-11
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report here fast A-site cation cross-exchange between APbX(3) perovskite nanocrystals (NCs) made of different A-cations (Cs (cesium), FA (formamidinium), and MA (methylammonium)) at room temperature. Surprisingly, the A-cation cross-exchange proceeds as fast as the halide (X=Cl, Br, or I) exchange with the help of free A-oleate complexes present in the freshly prepared colloidal perovskite NC solutions. This enabled the preparation of double (MACs, MAFA, CsFA)- and triple (MACsFA)-cation perovskite NCs with an optical band gap that is finely tunable by their A-site composition. The optical spectroscopy together with structural analysis using XRD and atomically resolved high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and integrated differential phase contrast (iDPC) STEM indicates the homogeneous distribution of different cations in the mixed perovskite NC lattice. Unlike halide ions, the A-cations do not phase-segregate under light illumination.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000823857300001 Publication Date 2022-06-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 16.6 Times cited 28 Open Access OpenAccess
Notes L.P. acknowledges the support from the Spanish Ministerio de Ciencia e Innovacion through Ramon y Cajal grant (RYC2018-026103-I) and the Spanish State Research Agency (Grant No. PID2020-117371RA-I00), the grant from the Xunta de Galicia (ED431F2021/05). N.J.S. acknowledges financial support from the Research Foundation-Flanders via a postdoctoral fellowship (FWO Grant No. 1238622N). S.B. thanks the financial support of the European Research Council (ERC-CoG-2019815128) and of the European Commission (EUSMI, Grant 731019). R.L.Z.H. thanks the Royal Academy of Engineering through the Research Fellowships scheme (No.: RF\201718\1701). S.D.S. and K.J. acknowledge the Royal Society for funding. S.D.S. acknowledges the Royal Society and Tata Group (UF150033). The work has received funding from the European Research Council under the European Union's Horizon 2020 research and innovation programme (HYPERION -grant agreement no. 756962). The authors acknowledge the Engineering and Physical Sciences Research Council (EPSRC) for funding (EP/R023980/1). M.I. and L.M. acknowledge financial support from the Italian Ministry of University and Research (MIUR) through the Flag-Era JTC2019 project “Solution-Processed Perovskite/Graphene Nanocomposites for Self-Powered Gas Sensors” (PeroGaS). The authors acknowledge the Universidade de Vigo/CISUG for open access funding. Approved Most recent IF: 16.6
Call Number UA @ admin @ c:irua:189675 Serial 7083
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Author Gonzalez, V.; Fazlic, I.; Cotte, M.; Vanmeert, F.; Gestels, A.; De Meyer, S.; Broers, F.; Hermans, J.; van Loon, A.; Janssens, K.; Noble, P.; Keune, K.
Title Lead(II) formate in Rembrandt's Night Watch : detection and distribution from the macro- to the micro-scale Type A1 Journal article
Year 2023 Publication Angewandte Chemie: international edition in English Abbreviated Journal
Volume Issue Pages 1-9
Keywords A1 Journal article; Art; Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract The Night Watch, painted in 1642 and on view in the Rijksmuseum in Amsterdam, is considered Rembrandt's most famous work. X-ray powder diffraction (XRPD) mapping at multiple length scales revealed the unusual presence of lead(II) formate, Pb(HCOO)(2), in several areas of the painting. Until now, this compound was never reported in historical oil paints. In order to get insights into this phenomenon, one possible chemical pathway was explored thanks to the preparation and micro-analysis of model oil paint media prepared by heating linseed oil and lead(II) oxide (PbO) drier as described in 17(th) century recipes. Synchrotron radiation based micro-XRPD (SR-mu-XRPD) and infrared microscopy were combined to identify and map at the micro-scale various neo-formed lead-based compounds in these model samples. Both lead(II) formate and lead(II) formate hydroxide Pb(HCOO)(OH) were detected and mapped, providing new clues regarding the reactivity of lead driers in oil matrices in historical paintings.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000920584500001 Publication Date 2023-01-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 16.6 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 16.6; 2023 IF: 11.994
Call Number UA @ admin @ c:irua:194279 Serial 7318
Permanent link to this record
 
 
Author Liang, Z.; Batuk, M.; Orlandi, F.; Manuel, P.; Hadermann, J.; Hayward, M.A.
Title Disproportionation of Co2+ in the topochemically reduced oxide LaSrCoRuO₅ Type A1 Journal article
Year 2024 Publication Angewandte Chemie: international edition in English Abbreviated Journal
Volume 63 Issue 6 Pages e202313067-5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Complex transition-metal oxides exhibit a wide variety of chemical and physical properties which are a strong function the local electronic states of the transition-metal centres, as determined by a combination of metal oxidation state and local coordination environment. Topochemical reduction of the double perovskite oxide, LaSrCoRuO6, using Zr, yields LaSrCoRuO5. This reduced phase contains an ordered array of apex-linked square-based pyramidal Ru3+O5, square-planar Co1+O4 and octahedral Co3+O6 units, consistent with the coordination-geometry driven disproportionation of Co2+. Coordination-geometry driven disproportionation of d(7) transition-metal cations (e.g. Rh2+, Pd3+, Pt3+) is common in complex oxides containing 4d and 5d metals. However, the weak ligand field experienced by a 3d transition-metal such as cobalt leads to the expectation that d(7+) Co2+ should be stable to disproportionation in oxide environments, so the presence of Co1+O4 and Co3+O6 units in LaSrCoRuO5 is surprising. Low-temperature measurements indicate LaSrCoRuO5 adopts a ferromagnetically ordered state below 120 K due to couplings between S=(1)/(2) Ru3+ and S=1 Co1+.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001136579700001 Publication Date 2023-12-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record
Impact Factor (down) 16.6 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 16.6; 2024 IF: 11.994
Call Number UA @ admin @ c:irua:202801 Serial 9023
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Author Van Gordon, K.; Ni, B.; Girod, R.; Mychinko, M.; Bevilacqua, F.; Bals, S.; Liz‐Marzán, L.M.
Title Single Crystal and Pentatwinned Gold Nanorods Result in Chiral Nanocrystals with Reverse Handedness Type A1 Journal Article
Year 2024 Publication Angewandte Chemie International Edition Abbreviated Journal Angew Chem Int Ed
Volume Issue Pages
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract Handedness is an essential attribute of chiral nanocrystals, having a major influence on their properties. During chemical growth, the handedness of nanocrystals is usually tuned by selecting the corresponding enantiomer of chiral molecules involved in asymmetric growth, often known as chiral inducers. We report that, even using the same chiral inducer enantiomer, the handedness of chiral gold nanocrystals can be reversed by using Au nanorod seeds with either single crystalline or pentatwinned structure. This effect holds for chiral growth induced both by amino acids and by chiral micelles. Although it was challenging to discern the morphological handedness for<italic>L</italic>‐cystine‐directed particles, even using electron tomography, both cases showed circular dichroism bands of opposite sign, with nearly mirrored chiroptical signatures for chiral micelle‐directed growth, along with quasi‐helical wrinkles of inverted handedness. These results expand the chiral growth toolbox with an effect that might be exploited to yield a host of interesting morphologies with tunable optical properties.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-05-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851 ISBN Additional Links
Impact Factor (down) 16.6 Times cited Open Access
Notes Ana Sánchez-Iglesias is acknowledged for support in the synthesis of pentatwinned gold nanorods. The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.), from MCIN/AEI/10.13039/501100011033 (Grant PID2020- 117779RB-I00 to L.M.L.-M and FPI Fellowship PRE2021- 097588 to K.V.G.), and by KU Leuven (C14/22/085). This work has been funded by the European Union under Project 101131111—DELIGHT. Funding for open access charge: Universidade de Vigo/ CRUE-CISUG. Approved Most recent IF: 16.6; 2024 IF: 11.994
Call Number EMAT @ emat @ Serial 9129
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Author Zhou, R.; Zhou, R.; Xian, Y.; Fang, Z.; Lu, X.; Bazaka, K.; Bogaerts, A.; Ostrikov, K.(K.)
Title Plasma-enabled catalyst-free conversion of ethanol to hydrogen gas and carbon dots near room temperature Type A1 Journal article
Year 2020 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 382 Issue 382 Pages 122745
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Selective conversion of bio-renewable ethanol under mild conditions especially at room temperature remains a major challenge for sustainable production of hydrogen and valuable carbon-based materials. In this study, adaptive non-thermal plasma is applied to deliver pulsed energy to rapidly and selectively reform ethanol in the absence of a catalyst. Importantly, the carbon atoms in ethanol that would otherwise be released into the environment in the form of CO or CO2 are effectively captured in the form of carbon dots (CDs). Three modes of non-thermal spark plasma discharges, i.e. single spark mode (SSM), multiple spark mode (MSM) and gliding spark mode (GSM), provide additional flexibility in ethanol reforming by controlling the processes of energy transfer and distribution, thereby affecting the flow rate, gas content, and energy consumption in H-2 production. A favourable combination of low temperature (< 40 degrees C), attractive conversion rate (gas flow rate of similar to 120 mL/min), high hydrogen yield (H-2 content > 90%), low energy consumption (similar to 0.96 kWh/m(3) H-2) and the effective generation of photoluminescent CDs (which are applicable for bioimaging or biolabelling) in the MSM indicate that the proposed strategy may offer a new carbon-negative avenue for comprehensive utilization of alcohols and mitigating the increasingly severe energy and environmental issues.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000503381200200 Publication Date 2019-09-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947; 1873-3212 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited 20 Open Access
Notes ; ; Approved Most recent IF: 15.1; 2020 IF: 6.216
Call Number UA @ admin @ c:irua:165648 Serial 6318
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Author Andersen, Ja.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad.
Title Plasma-catalytic dry reforming of methane: Screening of catalytic materials in a coaxial packed-bed DBD reactor Type A1 Journal article
Year 2020 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 397 Issue Pages 125519
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The combination of catalysis with non-thermal plasma is a promising alternative to thermal catalysis. A dielectric-barrier discharge reactor was used to study plasma-catalytic dry reforming of methane at ambient pressure and temperature and a fixed plasma power of 45 W. The effect of different catalytic packing materials was evaluated in terms of conversion, product selectivity, and energy efficiency. The conversion of CO2 (~22%) and CH4 (~33%) were found to be similar in plasma-only and when introducing packing materials in plasma. The main reason is the shorter residence time of the gas due to packing geometry, when compared at identical flow rates. H2, CO, C2-C4 hydrocarbons, and oxygenates were identified in the product gas. High selectivity towards H2 and CO were found for all catalysts and plasma-only, with a H2/CO molar ratio of ~0.9. The lowest syngas selectivity was obtained with Cu/Al2O3 (~66%), which instead, had the highest alcohol selectivity (~3.6%).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000542296100011 Publication Date 2020-05-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access
Notes Department of Chemical and Biochemical Engineering, Technical University of Denmark; We thank Haldor Topsoe A/S for providing all the catalytic materials used and the Department of Chemical and Biochemical Engineering, Technical University of Denmark, for funding this project. Approved Most recent IF: 15.1; 2020 IF: 6.216
Call Number PLASMANT @ plasmant @c:irua:170613 Serial 6406
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Author Girard-Sahun, F.; Biondo, O.; Trenchev, G.; van Rooij, G.; Bogaerts, A.
Title Carbon bed post-plasma to enhance the CO2 conversion and remove O2 from the product stream Type A1 Journal article
Year 2022 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 442 Issue Pages 136268
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract CO2 conversion by plasma technology is gaining increasing interest. We present a carbon (charcoal) bed placed after a Gliding Arc Plasmatron (GAP) reactor, to enhance the CO2 conversion, promote O/O2 removal and in­ crease the CO fraction in the exhaust mixture. By means of an innovative (silo) system, the carbon is constantly supplied, to avoid carbon depletion upon reaction with O/O2. Using this carbon bed, the CO2 conversion is enhanced by almost a factor of two (from 7.6 to 12.6%), while the CO concentration even increases by a factor of three (from 7.2 to 21.9%), and O2 is completely removed from the exhaust mixture. Moreover, the energy ef­ ficiency of the conversion process drastically increases from 27.9 to 45.4%, and the energy cost significantly drops from 41.9 to 25.4 kJ.L− 1. We also present the temperature as a function of distance from the reactor outlet, as well as the CO2, CO and O2 concentrations and the temperature in the carbon bed as a function of time, which is important for understanding the underlying mechanisms. Indeed, these time-resolved measurements reveal that the initial enhancements in CO2 conversion and in CO concentration are not maintained in our current setup. Therefore, we present a model to study the gasification of carbon with different feed gases (i.e., O2, CO and CO2 separately), from which we can conclude that the oxygen coverage at the surface plays a key role in determining the product composition and the rate of carbon consumption. Indeed, our model insights indicate that the drop in CO2 conversion and in CO concentration after a few minutes is attributed to deactivation of the carbon bed, due to rapid formation of oxygen complexes at the surface.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000797716700002 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes Horizon 2020 Marie Skłodowska-Curie Actions; European Research Council; 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) and the European Union’s Horizon 2020 Research and Inno­vation programme under the Marie Sklodowska-Curie grant agreement No 813393 (PIONEER). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Approved Most recent IF: 15.1
Call Number PLASMANT @ plasmant @c:irua:188286 Serial 7052
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Author Girard-Sahun, F.; Biondo, O.; Trenchev, G.; van Rooij, G.; Bogaerts, A.
Title Carbon bed post-plasma to enhance the CO2 conversion and remove O2 from the product stream Type A1 Journal article
Year 2022 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 442 Issue Pages 136268
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract CO2 conversion by plasma technology is gaining increasing interest. We present a carbon (charcoal) bed placed after a Gliding Arc Plasmatron (GAP) reactor, to enhance the CO2 conversion, promote O/O2 removal and in­ crease the CO fraction in the exhaust mixture. By means of an innovative (silo) system, the carbon is constantly supplied, to avoid carbon depletion upon reaction with O/O2. Using this carbon bed, the CO2 conversion is enhanced by almost a factor of two (from 7.6 to 12.6%), while the CO concentration even increases by a factor of three (from 7.2 to 21.9%), and O2 is completely removed from the exhaust mixture. Moreover, the energy ef­ ficiency of the conversion process drastically increases from 27.9 to 45.4%, and the energy cost significantly drops from 41.9 to 25.4 kJ.L− 1. We also present the temperature as a function of distance from the reactor outlet, as well as the CO2, CO and O2 concentrations and the temperature in the carbon bed as a function of time, which is important for understanding the underlying mechanisms. Indeed, these time-resolved measurements reveal that the initial enhancements in CO2 conversion and in CO concentration are not maintained in our current setup. Therefore, we present a model to study the gasification of carbon with different feed gases (i.e., O2, CO and CO2 separately), from which we can conclude that the oxygen coverage at the surface plays a key role in determining the product composition and the rate of carbon consumption. Indeed, our model insights indicate that the drop in CO2 conversion and in CO concentration after a few minutes is attributed to deactivation of the carbon bed, due to rapid formation of oxygen complexes at the surface.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000797716700002 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes Horizon 2020 Marie Skłodowska-Curie Actions; European Research Council; 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) and the European Union’s Horizon 2020 Research and Inno­vation programme under the Marie Sklodowska-Curie grant agreement No 813393 (PIONEER). The calculations were performed 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. We also thank R. De Meyer, K. Leyssens and S. Defossé for performing the charcoal characterizations. Approved Most recent IF: 15.1
Call Number PLASMANT @ plasmant @c:irua:188286 Serial 7053
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Author Van Alphen, S.; Ahmadi Eshtehardi, H.; O'Modhrain, C.; Bogaerts, J.; Van Poyer, H.; Creel, J.; Delplancke, M.-P.; Snyders, R.; Bogaerts, A.
Title Effusion nozzle for energy-efficient NOx production in a rotating gliding arc plasma reactor Type A1 Journal article
Year 2022 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 443 Issue Pages 136529
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma-based NOx production is of interest for sustainable N2 fixation, but more research is needed to improve its performance. One of the current limitations is recombination of NO back into N2 and O2 molecules immediately after the plasma reactor. Therefore, we developed a novel so-called “effusion nozzle”, to improve the perfor­mance of a rotating gliding arc plasma reactor for NOx production, but the same principle can also be applied to other plasma types. Experiments in a wide range of applied power, gas flow rates and N2/O2 ratios demonstrate an enhancement in NOx concentration by about 8%, and a reduction in energy cost by 22.5%. In absolute terms, we obtain NOx concentrations up to 5.9%, at an energy cost down to 2.1 MJ/mol, which are the best values reported to date in literature. In addition, we developed four complementary models to describe the gas flow, plasma temperature and plasma chemistry, aiming to reveal why the effusion nozzle yields better performance. Our simulations reveal that the effusion nozzle acts as very efficient heat sink, causing a fast drop in gas tem­perature when the gas molecules leave the plasma, hence limiting the recombination of NO back into N2 and O2. This yields an overall higher NOx concentration than without the effusion nozzle. This immediate quenching right at the end of the plasma makes our effusion nozzle superior to more conventional cooling options, like water cooling In addition, this higher NOx concentration can be obtained at a slightly lower power, because the effusion nozzle allows for the ignition and sustainment of the plasma at somewhat lower power. Hence, this also explains the lower energy cost. Overall, our experimental results and detailed modeling analysis will be useful to improve plasma-based NOx production in other plasma reactors as well.
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Publisher Place of Publication Editor
Language Wos 000800010600003 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
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ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project), and through long-term structural funding (Methusalem). The calculations were performed 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: 15.1
Call Number PLASMANT @ plasmant @c:irua:188283 Serial 7057
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Author Wang, Y.; Chen, Y.; Harding, J.; He, H.; Bogaerts, A.; Tu, X.
Title Catalyst-free single-step plasma reforming of CH4 and CO2 to higher value oxygenates under ambient conditions Type A1 Journal article
Year 2022 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 450 Issue Pages 137860
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Direct conversion of CH4 and CO2 to liquid fuels and chemicals under mild conditions is appealing for biogas conversion and utilization but challenging due to the inert nature of both gases. Herein, we report a promising plasma process for the catalyst-free single-step conversion of CH4 and CO2 into higher value oxygenates (i.e., methanol, acetic acid, ethanol, and acetone) at ambient pressure and room temperature using a water-cooled dielectric barrier discharge (DBD) reactor, with methanol being the main liquid product. The distribution of liquid products could be tailored by tuning the discharge power, reaction temperature and residence time. Lower discharge powers (10–15 W) and reaction temperatures (5–20 ◦ C) were favourable for the production of liquid products, achieving the highest methanol selectivity of 43% at 5 ◦ C and 15 W. A higher discharge power and reaction temperature, on the other hand, produced more gaseous products, particularly H2 (up to 26% selec­tivity) and CO (up to 33% selectivity). In addition, varying these process parameters (discharge power, reaction temperature and residence time) resulted in a simultaneous change in key discharge properties, such as mean electron energy (Ee), electron density (ne) and specific energy input (SEI), all of which are essential determiners of plasma chemical reactions. According to the results of artificial neural network (ANN) models, the relative importance of these process parameters and key discharge indicators on reaction performance follows the order: discharge power > reaction temperature > residence time, and SEI > ne > Ee, respectively. This work provides new insights into the contributions and tuning mechanism of multiple parameters for optimizing the reaction performance (e.g., liquid production) in the plasma gas conversion process.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000830813300004 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes This project received funding from the European Union’s Horizon 2020 research and innovation program under the Marie SklodowskaCurie grant agreement No. 813393. Approved Most recent IF: 15.1
Call Number PLASMANT @ plasmant @c:irua:189502 Serial 7100
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Author Lang, X.; Ouyang, Y.; Vandewalle, L.A.; Goshayeshi, B.; Chen, S.; Madanikashani, S.; Perreault, P.; Van Geem, K.M.; van Geem, K.M.
Title Gas-solid hydrodynamics in a stator-rotor vortex chamber reactor Type A1 Journal article
Year 2022 Publication Chemical engineering journal Abbreviated Journal Chem Eng J
Volume 446 Issue 5 Pages 137323-12
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The gas-solid vortex reactor (GSVR) has enormous process intensification potential. However the huge gas consumption can be a serious disadvantage for the GSVR in some applications such as fast pyrolysis. In this work, we demonstrate a recent novel design, where a stator-rotor vortex chamber (STARVOC) is driven by the fluid's kinetic energy, to decouple the solids bed rotation and gas. Gas-solid fluidization by using air and monosized aluminum balls was performed to investigate the hydrodynamics. A constructed fluidization flow regime map for a fixed solids loading of 100 g shows that the bed can only be fluidized for a rotation speed between 200 and 400 RPM. Below 200 RPM, particles settle down on the bottom plate and cannot form a stable bed due to inertia and friction. Above 400 RPM, the bed cannot be fluidized with superficial velocities up to 1.8 m/s (air flow rate of 90 Nm(3)/h). The bed thickness shows some non-uniformities, being smaller at the top of the bed than at the bottom counterpart. However by increasing the air flow rate or rotation speed the axial nonuniformity can be resolved. The bed pressure drop first increases with increasing gas flow rate and then levels off, showing similar characteristics as conventional fluidized beds. Theoretical pressure drops calculated from mathematical models such as Kao et al. model agree well with experimental measurements. Particle velocity discrepancies between the top and bottom particles reveal that the impact of gravity cannot be completely neglected. Design guidelines and possible applications for further development of STARVOC concept are proposed based on fundamental data provided in this work.
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Publisher Place of Publication Editor
Language Wos 000833418100006 Publication Date 2022-06-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947; 1873-3212 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 15.1
Call Number UA @ admin @ c:irua:189283 Serial 7167
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Author Wang, J.; Zhang, K.; Bogaerts, A.; Meynen, V.
Title 3D porous catalysts for plasma-catalytic dry reforming of methane : how does the pore size affect the plasma-catalytic performance? Type A1 Journal article
Year 2023 Publication Chemical engineering journal Abbreviated Journal
Volume 464 Issue Pages 142574-12
Keywords A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The effect of pore size on plasma catalysis is crucial but still unclear. Studies have shown plasma cannot enter micropores and mesopores, so catalysts for traditional thermocatalysis may not fit plasma catalysis. Here, 3D porous Cu and CuO with different pore sizes were prepared using uniform silica particles (10–2000 nm) as templates, and compared in plasma-catalytic dry reforming. In most cases, the smaller the pore size, the higher the conversion of CH4 and CO2. Large pores reachable by more electrons did not improve the reaction efficiency. We attribute this to the small surface area and large crystallite size, as indicated by N2-sorption, mercury intrusion and XRD. While the smaller pores might not be reachable by electrons, due to the sheath formed in front of them, as predicted by modeling, they can still be reached by radicals formed in the plasma, and ions can even be attracted into these pores. An exception are the samples synthesized from 1 μm silica, which show better performance. We believe this is due to the electric field enhancement for pore sizes close to the Debye length. The performances of CuO and Cu with different pore sizes can provide references for future research on oxide supports and metal components of plasma catalysts.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000966076400001 Publication Date 2023-03-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947; 1873-3212 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 15.1; 2023 IF: 6.216
Call Number UA @ admin @ c:irua:194862 Serial 7262
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Author Andersen, Ja.; Holm, Mc.; van 't Veer, K.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad.
Title Plasma-catalytic ammonia synthesis in a dielectric barrier discharge reactor: A combined experimental study and kinetic modeling Type A1 Journal article
Year 2023 Publication Chemical engineering journal Abbreviated Journal
Volume 457 Issue Pages 141294
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma-catalytic ammonia synthesis in a dielectric barrier discharge reactor has emerged as a possible route for electrification of nitrogen fixation. In this study, we use a combination of experiments and a plasma kinetic model to investigate the ammonia synthesis from N2 and H2, both with and without a solid packing material in the plasma zone. The effect of plasma power, feed flow rate, N2:H2 feed ratio, gas residence time, temperature, and packing material (MgAl2O4 alone or impregnated with Co or Ru) on the ammonia synthesis rate were examined in the experiments. The kinetic model was employed to improve our understanding of the ammonia formation pathways and identify possible changes in these pathways when altering the N2:H2 feed ratio. A higher NH3 synthesis rate was achieved when increasing the feed flow rate, as well as when increasing the gas tem-perature from 100 to 200 ◦C when a packing material was present in the plasma. At the elevated temperature of 200 ◦C, an optimum in the NH3 synthesis rate was observed at an equimolar feed ratio (N2:H2 =1:1) for the plasma alone and MgAl2O4, while a N2-rich feed was favored for Ru/MgAl2O4 and Co/MgAl2O4. The optimum in the synthesis rate with the N2-rich feed, where high energy electrons are more likely to collide with N2, suggests that the rate-limiting step is the dissociation of N2 in the gas phase. This is supported by the kinetic model when packing material was used. However, for the plasma alone, the model found that the N2 dissociation is only rate limiting in H2-rich feeds, whereas the limited access to H in N2-rich feeds makes the hydrogenation of N species limiting.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001058978000001 Publication Date 2023-01-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes We thank Topsoe A/S for providing the catalytic materials used in the study, the research group PLASMANT (University of Antwerp) for sharing their plasma kinetic model and allocating time on their cluster for the calculations, and the Department of Chemical and Biochemical Engineering (Technical University of Denmark) for funding the project. Approved Most recent IF: 15.1; 2023 IF: 6.216
Call Number PLASMANT @ plasmant @c:irua:195877 Serial 7234
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Author Morais, E.; Delikonstantis, E.; Scapinello, M.; Smith, G.; Stefanidis, G.D.; Bogaerts, A.
Title Methane coupling in nanosecond pulsed plasmas: Correlation between temperature and pressure and effects on product selectivity Type A1 Journal article
Year 2023 Publication Chemical engineering journal Abbreviated Journal
Volume 462 Issue Pages 142227
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We present a zero-dimensional kinetic model to characterise specifically the gas-phase dynamics of methane

conversion in a nanosecond pulsed discharge (NPD) plasma reactor. The model includes a systematic approach to

capture the nanoscale power discharges and the rapid ensuing changes in electric field, gas and electron temperature,

as well as species densities. The effects of gas temperature and reactor pressure on gas conversion and

product selectivity are extensively investigated and validated against experimental work. We discuss the

important reaction pathways and provide an analysis of the dynamics of the heating and cooling mechanisms. H

radicals are found to be the most populous plasma species and they participate in hydrogenation and dehydrogenation

reactions, which are the dominant recombination reactions leading to C2H4 and C2H2 as main

products (depending on the pressure).
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000983631500001 Publication Date 2023-03-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes We gratefully acknowledge financial support by the Flemish Government through the Moonshot cSBO project “Power-to-Olefins” (P2O; HBC.2020.2620). Approved Most recent IF: 15.1; 2023 IF: 6.216
Call Number PLASMANT @ plasmant @c:irua:195881 Serial 7246
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Author Van Alphen, S.; Hecimovic, A.; Kiefer, C.K.; Fantz, U.; Snyders, R.; Bogaerts, A.
Title Modelling post-plasma quenching nozzles for improving the performance of CO2 microwave plasmas Type A1 Journal article
Year 2023 Publication Chemical engineering journal Abbreviated Journal
Volume 462 Issue Pages 142217
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Given the ecological problems associated to the CO2 emissions of fossil fuels, plasma technology has gained

interest for conversion of CO2 into value-added products. Microwave plasmas operating at atmospheric pressure

have proven to be especially interesting, due to the high gas temperatures inside the reactor (i.e. up to 6000 K)

allowing for efficient thermal dissociation of CO2 into CO and O2. However, the performance of these high

temperature plasmas is limited by recombination of CO back into CO2 once the gas cools down in the afterglow.

In this work, we computationally investigated several quenching nozzles, developed and experimentally tested

by Hecimovic et al., [1] for their ability to quickly cool the gas after the plasma, thereby quenching the CO

recombination reactions. Using a 3D computational fluid dynamics model and a quasi-1D chemical kinetics

model, we reveal that a reactor without nozzle lacks gas mixing between hot gas in the center and cold gas near

the reactor walls. Especially at low flow rates, where there is an inherent lack of convective cooling due to the

low gas flow velocity, the temperature in the afterglow remains high (between 2000 and 3000 K) for a relatively

long time (in the 0.1 s range). As shown by our quasi-1D chemical kinetics model, this results in a important loss

of CO due to recombination reactions. Attaching a nozzle in the effluent of the reactor induces fast gas quenching

right after the plasma. Indeed, it introduces (i) more convective cooling by forcing cool gas near the walls to mix

with hot gas in the center of the reactor, as well as (ii) more conductive cooling through the water-cooled walls of

the nozzle. Our model shows that gas quenching and the suppression of recombination reactions have more

impact at low flow rates, where recombination is the most limiting factor in the conversion process.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000962382600001 Publication Date 2023-03-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 15.1 Times cited Open Access OpenAccess
Notes This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project), and through long-term structural funding (Methusalem). The calculations were performed 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: 15.1; 2023 IF: 6.216
Call Number PLASMANT @ plasmant @c:irua:195889 Serial 7250
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