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Author Tinck, S.; Bogaerts, A.
Title Computational study of the CF4 /CHF3 / H2 /Cl2 /O2 /HBr gas phase plasma chemistry Type A1 Journal article
Year 2016 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 49 Issue 49 Pages 195203
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A modelling study is performed of high-density low-pressure inductively coupled CF4/CHF3/H2/Cl2/O2/HBr plasmas under different gas mixing ratios. A reaction set describing the complete plasma chemistry is presented and discussed. The gas fraction of each component in this mixture is varied to investigate the sensitivity of the plasma properties, like electron density, plasma potential and species densities, towards the gas mixing ratios. This research is of great interest for microelectronics applications because these gases are often combined in two (or more)-component mixtures, and mixing gases or changing the fraction of a gas can sometimes yield unwanted reaction products or unexpected changes in the overall plasma properties due to the increased chemical complexity of the system. Increasing the CF4 fraction produces more F atoms for chemical etching as expected, but also more prominently lowers the density of Cl atoms, resulting in an actual drop in the etch rate under certain conditions. Furthermore, CF4 decreases the free electron density when mixed with Cl2. However, depending on the other gas components, CF4 gas can also sometimes enhance free electron density. This is the case when HBr is added to the mixture. The addition of H2 to the gas mixture will lower the sputtering process, not only due to the lower overall positive ion density at higher H2 fractions, but also because more H+, H2 + and H3 + are present and they have very low sputter yields. In contrast, a larger Cl2 fraction results in more chemical etching but also in less physical sputtering due to a smaller abundance of positive ions. Increasing the O2 fraction in the plasma will always lower the etch rate due to more oxidation of the wafer surface and due to a lower plasma density. However, it is also observed that the density of F atoms can actually increase with rising O2 gas fraction. This is relevant to note because the exact balance between fluorination and oxidation is important for fine-tuning the overall etch rate and for control of the sidewall profile. Finally, HBr is often used as a chemical etcher, but when mixed with F- or Cl-containing gases, HBr creates the same diluting effects as Ar or He, because a

higher fraction results in less chemical etching but more (physical) sputtering.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000375255500017 Publication Date 2016-04-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 5 Open Access
Notes We acknowledge the Fund for Scientific Research Flanders (FWO) for financial support of this work. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 2.588
Call Number c:irua:132890 Serial 4062
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Author Tinck, S.; Bogaerts, A.
Title Role of vibrationally excited HBr in a HBr/He inductively coupled plasma used for etching of silicon Type A1 Journal article
Year 2016 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 49 Issue 49 Pages 245204
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this work, the role of vibrationally excited HBr (HBr(vib)) is computationally investigated for a HBr/He inductively coupled plasma applied for Si etching. It is found that at least 50% of all dissociations of HBr occur through HBr(vib). This additional dissociation pathway through HBr(vib) makes the plasma significantly more atomic. It also results in a slightly higher electron temperature (i.e. about 0.2 eV higher compared to simulation results where HBr(vib) is not included), as well as a higher gas temperature (i.e. about 50 K higher than without including HBr(vib)), due to the enhanced Franck–Condon heating through HBr(vib) dissociation,

at the conditions investigated. Most importantly, the calculated etch rate with HBr(vib) included in the model is a factor 3 higher than in the case without HBr(vib), due to the higher fluxes of etching species (i.e. H and Br), while the chemical composition of the wafer surface shows no significant difference. Our calculations clearly show the importance of including HBr(vib) for accurate modeling of HBr-containing plasmas.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000377427100020 Publication Date 2016-05-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited Open Access
Notes The Fund for Scientific Research Flanders (FWO) is acknowledged for financial support of this work (Grant no. 0880.212.840). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Prof. Mark Kushner is also gratefully acknowledged for the useful discussions and for providing the HPEM code. Approved Most recent IF: 2.588
Call Number c:irua:133457 Serial 4072
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Author Tinck, S.; Tillocher, T.; Dussart, R.; Neyts, E.C.; Bogaerts, A.
Title Elucidating the effects of gas flow rate on an SF6inductively coupled plasma and on the silicon etch rate, by a combined experimental and theoretical investigation Type A1 Journal article
Year 2016 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 49 Issue 49 Pages 385201
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Experiments show that the etch rate of Si with SF6 inductively coupled plasma (ICP) is significantly influenced by the absolute gas flow rate in the range of 50–600 sccm, with a maximum at around 200 sccm. Therefore, we numerically investigate the effects of the gas flow rate on the bulk plasma properties and on the etch rate, to obtain more insight in the underlying reasons of this effect. A hybrid Monte Carlo—fluid model is applied to simulate an SF6 ICP. It is found that the etch rate is influenced by two simultaneous effects: (i) the residence time of the gas and (ii) the temperature profile of the plasma in the ICP volume, resulting indeed in a maximum etch rate at 200 sccm.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384095900011 Publication Date 2016-08-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 1 Open Access
Notes We are very grateful to Mark Kushner for providing the computational model. The Fund for Scientific Research Flanders (FWO; grant no. 0880.212.840) is acknowledged for financial support of this work. The work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 2.588
Call Number c:irua:134867 Serial 4108
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Author Bogaerts, A.; Khosravian, N.; Van der Paal, J.; Verlackt, C.C.W.; Yusupov, M.; Kamaraj, B.; Neyts, E.C.
Title Multi-level molecular modelling for plasma medicine Type A1 Journal article
Year 2016 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 49 Issue 49 Pages 054002
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Modelling at the molecular or atomic scale can be very useful for obtaining a better insight in plasma medicine. This paper gives an overview of different atomic/molecular scale modelling approaches that can be used to study the direct interaction of plasma species with biomolecules or the consequences of these interactions for the biomolecules on a somewhat longer time-scale. These approaches include density functional theory (DFT), density functional based tight binding (DFTB), classical reactive and non-reactive molecular dynamics (MD) and united-atom or coarse-grained MD, as well as hybrid quantum mechanics/molecular mechanics (QM/MM) methods. Specific examples will be given for three important types of biomolecules, present in human cells, i.e. proteins, DNA and phospholipids found in the cell membrane. The results show that each of these modelling approaches has its specific strengths and limitations, and is particularly useful for certain applications. A multi-level approach is therefore most suitable for obtaining a global picture of the plasma–biomolecule interactions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368944100003 Publication Date 2015-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 11 Open Access
Notes This work is financially supported by the Fund for Scientific Research Flanders (FWO) and the Francqui Foundation. The calculations were carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. Approved Most recent IF: 2.588
Call Number c:irua:131571 Serial 3985
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Author Kapra, A.V.; Vodolazov, D.Y.; Misko, V.R.
Title Vortex transport in a channel with periodic constrictions Type A1 Journal article
Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 26 Issue 9 Pages 095010-95011
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By numerically solving the time-dependent Ginzburg-Landau equations in a type-II superconductor, characterized by a critical temperature T-c1, and the coherence length xi(1), with a channel formed by overlapping rhombuses (diamond-like channel) made of another type-II superconductor, characterized, in general, by different T-c2 and xi(2), we investigate the dynamics of driven vortex matter for varying parameters of the channel: the width of the neck connecting the diamond cells, the cell geometry, and the ratio between the coherence lengths in the bank and the channel. We analyzed samples with periodic boundary conditions (which we call 'infinite' samples) and finite-size samples (with boundaries for vortex entry/exit), and we found that by tuning the channel parameters, one can manipulate the vortex dynamics, e.g., change the transition from flux-pinned to flux-flow regime and tune the slope of the IV-curves. In addition, we analyzed the effect of interstitial vortices on these characteristics. The critical current of this device was studied as a function of the applied magnetic field, j(c)(H). The function j(c)(H) reveals a striking commensurability peak, in agreement with recent experimental observations. The obtained results suggest that the diamond channel, which combines the properties of pinning arrays and flux-guiding channels, can be a promising candidate for potential use in devices controlling magnetic flux motion.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000323073800016 Publication Date 2013-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 2 Open Access
Notes ; This work was supported by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.878; 2013 IF: 2.796
Call Number UA @ lucian @ c:irua:110737 Serial 3898
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Author Cayado, P.; De Keukeleere, K.; Garzón, A.; Perez-Mirabet, L.; Meledin, A.; De Roo, J.; Vallés, F.; Mundet, B.; Rijckaert, H.; Pollefeyt, G.; Coll, M.; Ricart, S.; Palau, A.; Gázquez, J.; Ros, J.; Van Tendeloo, G.; Van Driessche, I.; Puig, T.; Obradors, X.
Title Epitaxial YBa2Cu3O7−xnanocomposite thin films from colloidal solutions Type A1 Journal article
Year 2015 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 28 Issue 28 Pages 124007
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A methodology of general validity to prepare epitaxial nanocomposite films based on the use of colloidal solutions containing different crystalline preformed oxide nanoparticles ( ex situ nanocomposites) is reported. The trifluoroacetate (TFA) metal–organic chemical solution deposition route is used with alcoholic solvents to grow epitaxial YBa 2 Cu 3 O 7 (YBCO) films. For this reason stabilizing oxide nanoparticles in polar solvents is a challenging goal. We have used scalable nanoparticle synthetic methodologies such as thermal and microwave-assisted solvothermal techniques to prepare CeO 2 and ZrO 2 nanoparticles. We show that stable and homogeneous colloidal solutions with these nanoparticles can be reached using benzyl alcohol, triethyleneglycol, nonanoic acid, trifluoroacetic acid or decanoic acid as protecting ligands, thereby allowing subsequent mixing with alcoholic TFA solutions. An elaborate YBCO film growth analysis of these nanocomposites allows the identification of the different relevant growth phenomena, e.g. nanoparticles pushing towards the film surface, nanoparticle reactivity, coarsening and nanoparticle accumulation at the substrate interface. Upon mitigation of these effects, YBCO nanocomposite films with high self-field critical currents ( J c ∼ 3–4 MA cm −2 at 77 K) were reached, indicating no current limitation effects associated with epitaxy perturbation, while smoothed magnetic field dependences of the critical currents at high magnetic fields and decreased effective anisotropic pinning behavior confirm the effectiveness of the novel developed approach to enhance vortex pinning. In conclusion, a novel low cost solution-derived route to high current nanocomposite superconducting films and coated conductors has been developed with very promising features.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000366288100009 Publication Date 2015-11-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 32 Open Access
Notes All authors acknowledge the EU (EU-FP7 NMP-LA-2012-280432 EUROTAPES project). ICMAB acknowledges MINECO (MAT2014-51778-C2-1-R) and Generalitat de Catalunya (2014SGR 753 and Xarmae). UGhent acknowledges the Special Research Fund (BOF), the Research Foundation Flanders (FWO) and the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT). TEM microscopy work was conducted in the Catalan Institute of Nanoscience and Nanotechnology (ICN2). The authors acknowledge the ICN2 Electron Microscopy Division for offering access to their instruments and expertise. Part of the STEM microscopy work was conducted in 'Laboratorio de Microscopias Avanzadas' at the Instituto de Nanociencia de Aragon—Universidad de Zaragoza. The authors acknowledge the LMA-INA for offering access to their instruments and expertise. JG and MC also acknowledge the Ramon y Cajal program (RYC-2012-11709 and RYC-2013-12448 respectively). Approved Most recent IF: 2.878; 2015 IF: 2.325
Call Number c:irua:129593 Serial 3966
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Author Berdiyorov, G.; Harrabi, K.; Maneval, J.P.; Peeters, F.M.
Title Effect of pinning on the response of superconducting strips to an external pulsed current Type A1 Journal article
Year 2015 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 28 Issue 28 Pages 025004
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the anisotropic time-dependent Ginzburg-Landau theory we study the effect of ordered and disordered pinning on the time response of superconducting strips to an external current that switched on abruptly. The pinning centers result in a considerable delay of the response time of the system to such abrupt switching on of the current, whereas the output voltage is always larger when pinning is present. The resistive state in both cases are characterized either by dynamically stable phase-slip centers/lines or expanding in-time hot-spots, which are the main mechanisms for dissipation in current-carrying superconductors. We find that hot-spots are always initiated by the phase-slip state. However, the range of the applied current for the phase-slip state increases significantly when pinning is introduced. Qualitative changes are observed in the dynamics of the superconducting condensate in the presence of pinning.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000351046300010 Publication Date 2014-12-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 19 Open Access
Notes ; This work was supported by EU Marie Curie (Project No: 253057), the Flemish Science Foundation (FWO-Vl) and King Fahd University of Petroleum and Minerals, Saudi Arabia, under the IN131034 DSR project. ; Approved Most recent IF: 2.878; 2015 IF: 2.325
Call Number c:irua:125491 Serial 829
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Author Meledin, A.; Turner, S.; Cayado, P.; Mundet, B.; Solano, E.; Ricart, S.; Ros, J.; Puig, T.; Obradors, X.; Van Tendeloo, G.
Title Unique nanostructural features in Fe, Mn-doped YBCO thin films Type A1 Journal article
Year 2016 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 29 Issue 29 Pages 125009
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An attempt to grow a thin epitaxial composite film of YBa2Cu3O7−δ (YBCO) with spinel MnFe2O4 (MFO) nanoparticles on a LAO substrate using the CSD approach resulted in a decomposition of the spinel and various doping modes of YBCO with the Fe and Mn cations. These nanostructural effects lead to a lowering of T c and a slight J c increase in field. Using a combination of advanced transmission electron microscopy (TEM) techniques such as atomic resolution high-angle annular dark field scanning TEM, energy dispersive x-ray spectroscopy and electron energy-loss spectroscopy we have been able to decipher and characterize the effects of the Fe and Mn doping on the film architecture. The YBaCuFeO5 anion-deficient double perovskite phase was detected in the form of 3D inclusions as well as epitaxially grown lamellas within the YBCO matrix. These nano-inclusions play a positive role as pinning centers responsible for the J c/J sf (H) dependency smoothening at high magnetic fields in the YBCO-MFO films with respect to the pristine YBCO films.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000387680100001 Publication Date 2016-10-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 6 Open Access
Notes The authors gratefully acknowledge Prof. Dr. A. Abakumov and Dr. J. Gazquez for discussions and corrections. Part of this work was performed within the framework of the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280432), funded by the European Union. ICMAB research was financed by the Ministry of Economy and Competitiveness, and FEDER funds under the projects MAT2011-28874-C02-01, MAT2014-51778-C2-1-R, ENE2014-56109-C3-3-R and Consolider Nanoselect CSD2007-00041, and by Generalitat de Catalunya (2009 SGR 770, 2015 SGR 753 and Xarmae). ICMAB acknowledges support from Severo Ochoa Program (MINECO, Grant SEV-2015-0496). Approved Most recent IF: 2.878
Call Number EMAT @ emat @ c:irua:136444 Serial 4295
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Author Nistor, L.C.; Nistor, S.V.; Dinca, G.; Georgeoni, P.; van Landuyt, J.; Manfredotti, C.; Vittone, E.
Title Microstructure and spectroscopy studies on cubic boron nitride synthesized under high-pressure conditions Type A1 Journal article
Year 2002 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 14 Issue 44 Pages 10983-10988
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High-resolution electron microscopy (HREM) studies of the microstructure and specific defects in hexagonal boron nitride (h-BN) precursors and cubic boron nitride (c-BN) crystals made under high-pressure high-temperature conditions revealed the presence of half-nanotubes at the edges of the h-BN particles. Their sp(3) bonding tendency could strongly influence the nucleation rates of c-BN. The atomic resolution at extended dislocations was insufficient to allow us to determine the stacking fault energy in the c-BN crystals. Its mean value of 191 +/- 15 mJ m(-2) is of the same order of magnitude as that of diamond. High-frequency (94 GHz) electron paramagnetic resonance studies on c-BN single crystals have produced new data on the D1 centres associated with the boron species. Ion-beam-induced luminescence measurements have indicated that c-BN is a very interesting luminescent material, which is characterized by four luminescence bands and exhibits a better resistance to ionizing radiation than CVD diamond.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000179541700114 Publication Date 2002-10-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 7 Open Access
Notes Approved Most recent IF: 2.649; 2002 IF: 1.775
Call Number UA @ lucian @ c:irua:103328 Serial 2061
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Author Simoen, E.; Loo, R.; Claeys, C.; de Gryse, O.; Clauws, P.; van Landuyt, J.; Lebedev, O.
Title Optical spectroscopy of oxygen precipitates in heavily doped p-type silicon Type A1 Journal article
Year 2002 Publication Journal of physics : condensed matter T2 – Conference on Extended Defects in Semiconductors (EDS 2002), JUN 01-06, 2002, BOLOGNA, ITALY Abbreviated Journal J Phys-Condens Mat
Volume 14 Issue 48 Pages 13185-13193
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Results are presented on the photoluminescence (PL) characterization of heavily doped p(+) Czochralski silicon, which has been subjected to a two-step, oxygen precipitation heat treatment. It will be shown that the presence of oxygen precipitates gives rise to the D1, D2 and D5 lines, where the energy of the D1 line shifts to lower values for a stronger degree of precipitation. The occurrence of these PL features is also a function of the boron concentration in the p(+) material. The PL results are compared with Fourier transform infrared absorption data and with transmission electron microscope, results. From this, it is concluded that PL has a good potential for use in the assessment of oxygen precipitation in heavily doped silicon.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000180091100068 Publication Date 2002-11-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 3 Open Access
Notes Approved Most recent IF: 2.649; 2002 IF: 1.775
Call Number UA @ lucian @ c:irua:103326 Serial 2477
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Author Borza, S.; Peeters, F.M.; Vasilopoulos, P.; Papp, G.
Title Electric-field manipulation of spin states in confined non-magnetic/magnetic heterostructures Type A1 Journal article
Year 2007 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 19 Issue 17 Pages 176221,1-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000246556400033 Publication Date 2007-04-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 4 Open Access
Notes Approved Most recent IF: 2.649; 2007 IF: 1.886
Call Number UA @ lucian @ c:irua:64758 Serial 885
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Author Xu, W.; Peeters, F.M.; Devreese, J.T.
Title Normal and hot electro-phonon resonance effect in a quasi-two-dimensional semiconductor system Type A1 Journal article
Year 1993 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 5 Issue 15 Pages 2307-2320
Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Abstract The electro-phonon resonance effect is a consequence of a resonant interaction between two electric subbands mediated by an optical phonon. It occurs in a quasi-two-dimensional electron system each time the energy difference between two electric subbands equals the energy of a Lo phonon. We study the influence of this effect on the electron mobility by using the momentum balance equation. The temperature and electron density dependences of the resonances are studied in the linear and non-linear response regimes.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1993KX70100004 Publication Date 2002-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.346 Times cited 18 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:102984 Serial 2367
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Author Spadaro, M.C.; Luches, P.; Bertoni, G.; Grillo, V.; Turner, S.; Van Tendeloo, G.; Valeri, S.; D'Addato, S.
Title Influence of defect distribution on the reducibility of CeO2-x nanoparticles Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 27 Issue 27 Pages 425705
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ceria nanoparticles (NPs) are fundamental in heterogeneous catalysis because of their ability to store or release oxygen depending on the ambient conditions. Their oxygen storage capacity is strictly related to the exposed planes, crystallinity, density and distribution of defects. In this work a study of ceria NPs produced with a ligand-free, physical synthesis method is presented. The NP films were grown by a magnetron sputtering based gas aggregation source and studied by high resolution- and scanning-transmission electron microscopy and x-ray photoelectron spectroscopy. In particular, the influence of the oxidation procedure on the NP reducibility has been investigated. The different reducibility has been correlated to the exposed planes, crystallinity and density and distribution of structural defects. The results obtained in this work represent a basis to obtain cerium oxide NP with desired oxygen transport properties.
Address Dipartimento FIM, Universita di Modena e Reggio Emilia, via G. Campi 213/a, I-41125 Modena, Italy. CNR-NANO, via G. Campi 213/a, I-41125 Modena, Italy
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000385483900004 Publication Date 2016-09-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 11 Open Access
Notes The authors gratefully acknowledge financial support by the Italian MIUR under grant FIRB RBAP115AYN (Oxides at the nanoscale: multifunctionality and applications). The activity is performed within the COST Action CM1104 'Reducible oxide chemistry, structure and functions'. The research leading to these results has received funding also from the European Union Seventh Framework Programme under Grant Agreement 312483—ESTEEM2 (Integrated Infrastructure Initiative–I3).; esteem2_ta Approved Most recent IF: 3.44
Call Number EMAT @ emat @ c:irua:135424 Serial 4130
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Author Kozák, T.; Bogaerts, A.
Title Evaluation of the energy efficiency of CO2 conversion in microwave discharges using a reaction kinetics model Type A1 Journal article
Year 2015 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 24 Issue 24 Pages 015024
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We use a zero-dimensional reaction kinetics model to simulate CO2 conversion in microwave discharges where the excitation of the vibrational levels plays a significant role in the dissociation kinetics. The model includes a description of the CO2 vibrational kinetics, taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is used to simulate a general tubular microwave reactor, where a stream of CO2 flows through a plasma column generated by microwave radiation. We study the effects of the internal plasma parameters, namely the reduced electric field, electron density and the total specific energy input, on the CO2 conversion and its energy efficiency. We report the highest energy efficiency (up to 30%) for a specific energy input in the range 0.41.0 eV/molecule and a reduced electric field in the range 50100 Td and for high values of the electron density (an ionization degree greater than 10−5). The energy efficiency is mainly limited by the VT relaxation which contributes dominantly to the vibrational energy losses and also contributes significantly to the heating of the reacting gas. The model analysis provides useful insight into the potential and limitations of CO2 conversion in microwave discharges.
Address
Corporate Author Thesis
Publisher Institute of Physics Place of Publication Bristol Editor
Language Wos 000348298200025 Publication Date 2014-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252;1361-6595; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 100 Open Access
Notes Approved Most recent IF: 3.302; 2015 IF: 3.591
Call Number c:irua:122243 Serial 1087
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Author Kolev, S.; Bogaerts, A.
Title A 2D model for a gliding arc discharge Type A1 Journal article
Year 2015 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 24 Issue 24 Pages 015025
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this study we report on a 2D fluid model of a gliding arc discharge in argon. Despite the 3D nature of the discharge, 2D models are found to be capable of providing very useful information about the operation of the discharge. We employ two modelsan axisymmetric and a Cartesian one. We show that for the considered experiment and the conditions of a low current arc (around 30 mA) in argon, there is no significant heating of the cathode surface and the discharge is sustained by field electron emission from the cathode accompanied by the formation of a cathode spot. The obtained discharge power and voltage are relatively sensitive to the surface properties and particularly to the surface roughness, causing effectively an amplification of the normal electric field. The arc body and anode region are not influenced by this and depend mainly on the current value. The gliding of the arc is modelled by means of a 2D Cartesian model. The arcelectrode contact points are analysed and the gliding mechanism along the electrode surface is discussed. Following experimental observations, the cathode spot is simulated as jumping from one point to another. A complete arc cycle is modelled from initial ignition to arc decay. The results show that there is no interaction between the successive gliding arcs.
Address
Corporate Author Thesis
Publisher Institute of Physics Place of Publication Bristol Editor
Language Wos 000348298200026 Publication Date 2014-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252;1361-6595; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 34 Open Access
Notes Approved Most recent IF: 3.302; 2015 IF: 3.591
Call Number c:irua:122538 c:irua:122538 c:irua:122538 c:irua:122538 Serial 3
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Author Peerenboom, K.; Parente, A.; Kozák, T.; Bogaerts, A.; Degrez, G.
Title Dimension reduction of non-equilibrium plasma kinetic models using principal component analysis Type A1 Journal article
Year 2015 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 24 Issue 24 Pages 025004
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The chemical complexity of non-equilibrium plasmas poses a challenge for plasma modeling because of the computational load. This paper presents a dimension reduction method for such chemically complex plasmas based on principal component analysis (PCA). PCA is used to identify a low-dimensional manifold in chemical state space that is described by a small number of parameters: the principal components. Reduction is obtained since continuity equations only need to be solved for these principal components and not for all the species. Application of the presented method to a CO2 plasma model including state-to-state vibrational kinetics of CO2 and CO demonstrates the potential of the PCA method for dimension reduction. A manifold described by only two principal components is able to predict the CO2 to CO conversion at varying ionization degrees very accurately.
Address
Corporate Author Thesis
Publisher Institute of Physics Place of Publication Bristol Editor
Language Wos 000356816200008 Publication Date 2015-01-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252;1361-6595; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 11 Open Access
Notes Approved Most recent IF: 3.302; 2015 IF: 3.591
Call Number c:irua:123534 Serial 704
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Author Kolev, S.; Bogaerts, A.
Title Similarities and differences between gliding glow and gliding arc discharges Type A1 Journal article
Year 2015 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 24 Issue 24 Pages 065023
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this work we have analyzed the properties of a gliding dc discharge in argon at atmospheric pressure. Despite the usual designation of these discharges as ‘gliding arc discharges’, it was found previously that they operate in two different regimes—glow and arc. Here we analyze the differences in both regimes by means of two dimensional fluid modeling. In order to address different aspects of the discharge operation, we use two models—Cartesian and axisymmetric in a cylindrical coordinate system. The obtained results show that the two types of discharges produce a similar plasma column for a similar discharge current. However, the different mechanisms of plasma channel attachment to the cathode could produce certain differences in the plasma parameters (i.e. arc elongation), and this can affect gas treatments applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368117100028 Publication Date 2015-11-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252;1361-6595; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 12 Open Access
Notes This work is financially supported by the Methusalem financing and by the IAP/7 (Inter-university Attraction Pole) program ‘Physical Chemistry of Plasma-Surface Interactions’ from the Belgian Federal Office for Science Policy (BELSPO). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen Approved Most recent IF: 3.302; 2015 IF: 3.591
Call Number c:irua:129214 Serial 3952
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Author Van Laer, K.; Bogaerts, A.
Title Fluid modelling of a packed bed dielectric barrier discharge plasma reactor Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 015002
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A packed bed dielectric barrier discharge plasma reactor is computationally studied with a fluid model. Two different complementary axisymmetric 2D geometries are used to mimic the intrinsic 3D problem. It is found that a packing enhances the electric field strength and electron temperature at the contact points of the dielectric material due to polarization of the beads by the applied potential. As a result, these contact points prove to be of direct importance to initiate the plasma. At low applied potential, the discharge stays at the contact points, and shows the properties of a Townsend discharge. When a high enough potential is applied, the plasma will be able to travel through the gaps in between the beads from wall to wall, forming a kind of glow discharge. Therefore, the inclusion of a so-called ‘channel of voids’ is indispensable in any type of packed bed modelling.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000370974800009 Publication Date 2015-12-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 50 Open Access
Notes The authors gratefully thank St Kolev for the many interesting discussions and the useful advise in setting up the models. This research was carried out in the framework of the network on Physical Chemistry of Plasma-Surface Interactions— Interuniversity Attraction Poles, phase VII (http://psi-iap7.ulb. ac.be/), and supported by the Belgian Science Policy Office (BELSPO). K Van Laer is indebted to the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT Flanders) for financial support. Approved Most recent IF: 3.302
Call Number c:irua:129802 Serial 3982
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Author Belov, I.; Paulussen, S.; Bogaerts, A.
Title Appearance of a conductive carbonaceous coating in a CO2dielectric barrier discharge and its influence on the electrical properties and the conversion efficiency Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 015023
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract This work examines the properties of a dielectric barrier discharge (DBD) reactor, built for CO2 decomposition, by means of electrical characterization, optical emission spectroscopy and gas chromatography. The discharge, formed in an electronegative gas (such as CO2, but also O2), exhibits clearly different electrical characteristics, depending on the surface conductivity of the reactor walls. An asymmetric current waveform is observed in the metaldielectric (MD) configuration, with sparse high-current pulses in the positive half-cycle (HC) and a more uniform regime in the negative HC. This indicates that the discharge is operating in two alternating regimes with rather different properties. At high CO2 conversion regimes, a conductive coating is deposited on the dielectric. This so-called coated MD configuration yields a symmetric current waveform, with current peaks in both the positive and negative HCs. In a double-dielectric (DD) configuration, the current waveform is also symmetric, but without current peaks in both the positive and negative HC. Finally, the DD configuration with conductive coating on the inner surface of the outer dielectric, i.e. so-called coated DD, yields again an asymmetric current waveform, with current peaks in the negative HC. These different electrical characteristics are related to the presence of the conductive coating on the dielectric wall of the reactor and can be explained by an increase of the local barrier capacitance available for charge transfer. The different discharge regimes affect the CO2 conversion, more specifically, the CO2 conversion is lowest in the clean DD configuration. It is somewhat higher in the coated DD configuration, and still higher in the MD configuration. The clean and coated MD configuration, however, gave similar CO2 conversion. These results indicate that the conductivity of the dielectric reactor walls can highly promote the development of the high-amplitude discharge current pulses and subsequently the CO2 conversion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000370974800030 Publication Date 2016-01-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 25 Open Access
Notes The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7-PEOPLE-2013-ITN) under Grant Agreement № 606889 (RAPID—Reactive Atmospheric Plasma processIng—eDucation network). Approved Most recent IF: 3.302
Call Number c:irua:130790 Serial 4006
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Author Ozkan, A.; Dufour, T.; Silva, T.; Britun, N.; Snyders, R.; Bogaerts, A.; Reniers, F.
Title The influence of power and frequency on the filamentary behavior of a flowing DBD—application to the splitting of CO2 Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 025013
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this experimental study, a flowing dielectric barrier discharge operating at atmospheric pressure is used for the splitting of CO2 into O2 and CO. The influence of the applied frequency and plasma power on the microdischarge properties is investigated to understand their role on the CO2 conversion. Electrical measurements are carried out to explain the conversion trends and to characterize the microdischarges through their number, their lifetime,

their intensity and the induced electrical charge. Their influence on the gas and electrode temperatures is also evidenced through optical emission spectroscopy and infrared imaging. It is shown that, in our configuration, the conversion depends mostly on the charge delivered in the plasma and not on the effective plasma voltage when the applied power is modified. Similarly, at constant total current, a better conversion is observed at low frequencies, where a less filamentary discharge regime with a higher effective plasma voltage than that at a higher

frequency is obtained.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000372337900015 Publication Date 2016-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 40 Open Access
Notes The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A Ozkan would like to thank the financial support given by ‘Fonds David et Alice Van Buuren’. N Britun is a postdoctoral researcher of the F.R.S.-FNRS, Belgium. Approved Most recent IF: 3.302
Call Number c:irua:131904 Serial 4021
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Author Trenchev, G.; Kolev, S.; Bogaerts, A.
Title A 3D model of a reverse vortex flow gliding arc reactor Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 035014
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this computational study, a gliding arc plasma reactor with a reverse-vortex flow stabilization is modelled for the first time by a fluid plasma description. The plasma reactor operates with argon gas at atmospheric pressure. The gas flow is simulated using the k-ε Reynolds-averaged Navier–Stokes turbulent model. A quasi-neutral fluid plasma model is used for computing the plasma properties. The plasma arc movement in the reactor is observed, and the results for the gas flow, electrical characteristics, plasma density, electron temperature, and gas temperature are analyzed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000376557400022 Publication Date 2016-04-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 20 Open Access
Notes This research was carried out in the framework of the network on Physical Chemistry of Plasma–Surface Interactions— Interuniversity Attraction Poles, phase VII (http://psi-iap7.ulb. ac.be/), and supported by the Belgian Science Policy Office (BELSPO), and it was also funded by the Fund for Scientific Research Flanders (FWO). Grant number: 11U5316N. Approved Most recent IF: 3.302
Call Number c:irua:132888 c:irua:132888 Serial 4063
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Author Ozkan, A.; Dufour, T.; Bogaerts, A.; Reniers, F.
Title How do the barrier thickness and dielectric material influence the filamentary mode and CO2conversion in a flowing DBD? Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 045016
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Dielectric barrier discharges (DBDs) are commonly used to generate cold plasmas at

atmospheric pressure. Whatever their configuration (tubular or planar), the presence of a dielectric barrier is mandatory to prevent too much charge build up in the plasma and the formation of a thermal arc. In this article, the role of the barrier thickness (2.0, 2.4 and 2.8 mm) and of the kind of dielectric material (alumina, mullite, pyrex, quartz) is investigated on the filamentary behavior in the plasma and on the CO2 conversion in a tubular flowing DBD, by means of mass spectrometry measurements correlated with electrical characterization and IR imaging. Increasing the barrier thickness decreases the capacitance, while preserving the electrical charge. As a result, the voltage over the dielectric increases and a larger number of microdischarges is generated, which enhances the CO2 conversion. Furthermore, changing the dielectric material of the barrier, while keeping the same geometry and dimensions, also affects the CO2 conversion. The highest CO2 conversion and energy efficiency are obtained for quartz and alumina, thus not following the trend of the relative permittivity. From the

electrical characterization, we clearly demonstrate that the most important parameters are the somewhat higher effective plasma voltage (yielding a somewhat higher electric field and electron energy in the plasma) for quartz, as well as the higher plasma current (and thus larger electron density) and the larger number of microdischarge filaments (mainly for alumina, but also for quartz). The latter could be correlated to the higher surface roughness for alumina and to the higher voltage over the dielectric for quartz.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000380380200030 Publication Date 2016-06-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 24 Open Access
Notes The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A. Ozkan would like to thank the financial support given by ‘Fonds David et Alice Van Buuren’. Approved Most recent IF: 3.302
Call Number c:irua:134396 Serial 4100
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Author Berthelot, A.; Bogaerts, A.
Title Modeling of plasma-based CO2conversion: lumping of the vibrational levels Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 045022
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Although CO2 conversion by plasma technology is gaining increasing interest, the

underlying mechanisms for an energy-efficient process are still far from understood. In this work, a reduced non-equilibrium CO2 plasma chemistry set, based on level lumping of the vibrational levels, is proposed and the reliability of this level-lumping method is tested by a self-consistent zero-dimensional code. A severe reduction of the number of equations to be solved is achieved, which is crucial to be able to model non-equilibrium CO2 plasmas by 2-dimensional models. Typical conditions of pressure and power used in a microwave plasma for CO2 conversion are investigated. Several different sets, using different numbers of lumped groups, are considered. The lumped models with 1, 2 or 3 groups are able to reproduce the gas temperature, electron density and electron temperature profiles, as calculated by the full model treating all individual excited levels, in the entire pressure range investigated. Furthermore, a 3-groups model is also able to reproduce the shape of the vibrational distribution function (VDF) and gives the most reliable prediction of the CO2 conversion. A strong influence of the vibrational excitation on the plasma characteristics is observed. Finally, the limitations of the lumped-levels method are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000380380200036 Publication Date 2016-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 33 Open Access
Notes This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 606889 and it was also carried out in the framework of the network on Physical Chemistry of Plasma-Surface Interactions—Interuniversity Attraction Poles, phase VII (PSI-IAP7) supported by the Belgian Science Policy Office (BELSPO). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. Approved Most recent IF: 3.302
Call Number c:irua:134397 Serial 4101
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Author Bruggeman, P.J.; Kushner, M.J.; Locke, B.R.; Gardeniers, J.G.E.; Graham, W.G.; Graves, D.B.; Hofman-Caris, R.C.H.M.; Maric, D.; Reid, J.P.; Ceriani, E.; Fernandez Rivas, D.; Foster, J.E.; Garrick, S.C.; Gorbanev, Y.; Hamaguchi, S.; Iza, F.; Jablonowski, H.; Klimova, E.; Kolb, J.; Krcma, F.; Lukes, P.; Machala, Z.; Marinov, I.; Mariotti, D.; Mededovic Thagard, S.; Minakata, D.; Neyts, E.C.; Pawlat, J.; Petrovic, Z.L.; Pflieger, R.; Reuter, S.; Schram, D.C.; Schröter, S.; Shiraiwa, M.; Tarabová, B.; Tsai, P.A.; Verlet, J.R.R.; von Woedtke, T.; Wilson, K.R.; Yasui, K.; Zvereva, G.
Title Plasma–liquid interactions: a review and roadmap Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 5 Pages 053002
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma–liquid interactions represent a growing interdisciplinary area of research involving plasma science, fluid dynamics, heat and mass transfer, photolysis, multiphase chemistry and aerosol science. This review provides an assessment of the state-of-the-art of this multidisciplinary area and identifies the key research challenges. The developments in diagnostics, modeling and further extensions of cross section and reaction rate databases that are necessary to address these challenges are discussed. The review focusses on nonequilibrium plasmas.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384715400001 Publication Date 2016-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 460 Open Access
Notes This manuscript originated from discussions at the Lorentz Center Workshop ‘Gas/Plasma–Liquid Interface: Transport, Chemistry and Fundamental Data’ that took place at the Lorentz Center, Leiden University in the Netherlands from August 4, through August 8, 2014, and follow-up discussions since the workshop. All authors acknowledge the support of the Lorentz Center, the COST action TD1208 (Electrical Discharges with Liquids for Future Applications) and the Royal Dutch Academy of Sciences for their financial support. PJB, MJK, DBG and JEF acknowledge the support of the ‘Center on Control of Plasma Kinetics’ of the United States Department of Energy Office of Fusion Energy Science (DE-SC0001319). In addition, PJB and BRL acknowledge the support of the National Science Foundation (PHY 1500135 and CBET 1236225, respectively). In addition the enormous help of Mrs. Victoria Piorek (University of Minnesota) in the formatting of the final document including the references is gratefully acknowledged. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @ c:irua:144654 Serial 4628
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Author Ozkan, A.; Dufour, T.; Silva, T.; Britun, N.; Snyders, R.; Reniers, F.; Bogaerts, A.
Title DBD in burst mode: solution for more efficient CO2conversion? Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 055005
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract CO2 conversion into value-added products has gained significant interest over the few last years, as the greenhouse gas concentrations constantly increase due to anthropogenic activities. Here we report on experiments for CO2 conversion by means of a cold atmospheric plasma using a cylindrical flowing dielectric barrier discharge (DBD) reactor. A detailed comparison of this DBD ignited in a so-called burst mode (i.e. where an AC voltage is applied during a limited amount of time) and pure AC mode is carried out to evaluate their effect on the conversion of CO2 as well as on the energy efficiency. Decreasing the duty cycle in the burst mode from 100% (i.e. corresponding to pure AC mode) to 40% leads to a rise in the

conversion from 16–26% and to a rise in the energy efficiency from 15 to 23%. Based on a detailed electrical analysis, we show that the conversion correlates with the features of the microfilaments. Moreover, the root-mean-square voltage in the burst mode remains constant as a function of the process time for the duty cycles <70%, while a higher duty cycle or the usual pure AC mode leads to a clear voltage decay by more than 500 V, over approximately 90 s, before reaching a steady state regime. The higher plasma voltage in the burst mode yields a higher electric field. This causes the increasing the electron energy, and therefore their

involvement in the CO2 dissociation process, which is an additional explanation for the higher CO2 conversion and energy efficiency in the burst mode.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000403945500005 Publication Date 2016-08-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 17 Open Access
Notes The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A. Ozkan would also like to thank financial support given by ‘Fonds David et Alice Van Buuren’. Approved Most recent IF: 3.302
Call Number c:irua:134841 Serial 4107
Permanent link to this record
 

 
Author Bogaerts, A.; Wang, W.; Berthelot, A.; Guerra, V.
Title Modeling plasma-based CO2conversion: crucial role of the dissociation cross section Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 055016
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma-based CO2 conversion is gaining increasing interest worldwide. A large research effort is devoted to improving the energy efficiency. For this purpose, it is very important to understand the underlying mechanisms of the CO2 conversion. The latter can be obtained by computer modeling, describing in detail the behavior of the various plasma species and all relevant chemical processes. However, the accuracy of the modeling results critically depends on the accuracy of the assumed input data, like cross sections. This is especially true for the cross section of electron impact dissociation, as the latter process is believed

to proceed through electron impact excitation, but it is not clear from the literature which excitation channels effectively lead to dissociation. Therefore, the present paper discusses the effect of different electron impact dissociation cross sections reported in the literature on the calculated CO2 conversion, for a dielectric barrier discharge (DBD) and a microwave (MW) plasma. Comparison is made to experimental data for the DBD case, to elucidate which cross section might be the most realistic. This comparison reveals that the cross sections proposed

by Itikawa and by Polak and Slovetsky both seem to underestimate the CO2 conversion. The cross sections recommended by Phelps with thresholds of 7 eV and 10.5 eV yield a CO2 conversion only slightly lower than the experimental data, but the sum of both cross sections overestimates the values, indicating that these cross sections represent dissociation, but most probably also include other (pure excitation) channels. Our calculations indicate that the choice of the electron impact dissociation cross section is crucial for the DBD, where this process is the dominant mechanism for CO2 conversion. In the MW plasma, it is only significant at pressures up to 100 mbar, while it is of minor importance for higher pressures, when dissociation proceeds mainly through collisions of CO2 with heavy particles.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384030600001 Publication Date 2016-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 57 Open Access
Notes The authors would like to thank R Snoeckx and S Heijkers for the interesting discussions. This research was supported by the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 606889, the European Marie Skłodowska-Curie Individual Fellowship project ‘GlidArc’ within Horizon2020, the FWO project (grant G.0383.16N), and the Network on Physical Chemistry of Plasma-Surface Interactions—Interuniversity Attraction Poles, phase VII (PSI-IAP7), supported by the Belgian Science Policy Office (BELSPO). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. VG was partially supported by the Portuguese FCT— Fundação para a Ci Approved Most recent IF: 3.302
Call Number c:irua:135070 Serial 4111
Permanent link to this record
 

 
Author Wang, W.; Bogaerts, A.
Title Effective ionisation coefficients and critical breakdown electric field of CO2at elevated temperature: effect of excited states and ion kinetics Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 055025
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Electrical breakdown by the application of an electric field occurs more easily in hot gases than in cold gases because of the extra electron-species interactions that occur as a result of dissociation, ionization and excitation at higher temperature. This paper discusses some overlooked physics and clarifies inaccuracies in the evaluation of the effective ionization coefficients and the critical reduced breakdown electric field of CO2 at elevated temperature, considering the influence of excited states and ion kinetics. The critical reduced breakdown electric field is obtained by balancing electron generation and loss mechanisms using the electron energy distribution function (EEDF) derived from the Boltzmann transport equation under the two-term approximation. The equilibrium compositions of the hot gas mixtures are determined based on Gibbs free energy minimization considering the ground states as well as vibrationally and electronically excited states as independent species, which follow a Boltzmann distribution with a fixed excitation temperature. The interaction cross sections between electrons and the excited species, not reported previously, are properly taken into account. Furthermore, the ion kinetics, including electron–ion recombination, associative electron detachment, charge transfer and ion conversion into stable negative ion clusters, are also considered. Our results indicate that the excited species lead to a greater population of high-energy electrons at higher gas temperature and this affects the Townsend rate coefficients (i.e. of electron impact ionization and attachment), but the critical reduced breakdown electric field strength of CO2 is only affected when also properly accounting for the ion kinetics. Indeed, the latter greatly influences the effective ionization coefficients and hence the critical reduced breakdown electric field at temperatures above 1500 K. The rapid increase of the dissociative electron attachment cross-section of molecular oxygen with rising vibrational quantum number leads to a larger electron loss rate and this enhances the critical reduced breakdown electric field strength in the temperature range where the concentration of molecular oxygen is relatively high. The results obtained in this work show reasonable agreement with experimental results from literature, and are important for the evaluation of the dielectric strength of CO2 in a highly reactive environment at elevated temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000385494000006 Publication Date 2016-09-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 3 Open Access
Notes Skłodowska-Curie Individual Fellowship ‘GlidArc’ within Horizon2020 (Grant No.657304) and the FWO project (grant G.0383.16N). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @ c:irua:135515 Serial 4281
Permanent link to this record
 

 
Author Wang, W.; Berthelot, A.; Kolev, S.; Tu, X.; Bogaerts, A.
Title CO2 conversion in a gliding arc plasma: 1D cylindrical discharge model Type A1 Journal article
Year 2016 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 25 Issue 25 Pages 065012
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract CO 2 conversion by a gliding arc plasma is gaining increasing interest, but the underlying mechanisms for an energy-efficient process are still far from understood. Indeed, the chemical complexity of the non-equilibrium plasma poses a challenge for plasma modeling due to the huge computational load. In this paper, a one-dimensional (1D) gliding arc model is developed in a cylindrical frame, with a detailed non-equilibrium CO 2 plasma chemistry set, including the CO 2 vibrational kinetics up to the dissociation limit. The model solves a set of time- dependent continuity equations based on the chemical reactions, as well as the electron energy balance equation, and it assumes quasi-neutrality in the plasma. The loss of plasma species and heat due to convection by the transverse gas flow is accounted for by using a characteristic frequency of convective cooling, which depends on the gliding arc radius, the relative velocity of the gas flow with respect to the arc and on the arc elongation rate. The calculated values for plasma density and plasma temperature within this work are comparable with experimental data on gliding arc plasma reactors in the literature. Our calculation results indicate that excitation to the vibrational levels promotes efficient dissociation in the gliding arc, and this is consistent with experimental investigations of the gliding arc based CO 2 conversion in the literature. Additionally, the dissociation of CO 2 through collisions with O atoms has the largest contribution to CO 2 splitting under the conditions studied. In addition to the above results, we also demonstrate that lumping the CO 2 vibrational states can bring a significant reduction of the computational load. The latter opens up the way for 2D or 3D models with an accurate description of the CO 2 vibrational kinetics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000386605100002 Publication Date 2016-10-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 3 Open Access
Notes This research was supported by the European Marie Skłodowska-Curie Individual Fellowship ‘GlidArc’ within Horizon2020 (Grant No. 657304) and by the FWO project (grant G.0383.16N). 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: 3.302
Call Number PLASMANT @ plasmant @ c:irua:135990 Serial 4286
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Author Sun, S.R.; Kolev, S.; Wang, H.X.; Bogaerts, A.
Title Coupled gas flow-plasma model for a gliding arc: investigations of the back-breakdown phenomenon and its effect on the gliding arc characteristics Type A1 Journal article
Year 2017 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 26 Issue 26 Pages 015003
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We present a 3D and 2D Cartesian quasi-neutral plasma model for a low current argon gliding arc discharge, including strong interactions between the gas flow and arc plasma column.

The 3D model is applied only for a short time of 0.2 ms due to its huge computational cost. It mainly serves to verify the reliability of the 2D model. As the results in 2D compare well with those in 3D, they can be used for a better understanding of the gliding arc basic characteristics. More specifically, we investigate the back-breakdown phenomenon induced by an artificially controlled plasma channel, and we discuss its effect on the gliding arc characteristics. The

back-breakdown phenomenon, or backward-jump motion of the arc, as observed in the experiments, results in a drop of the gas temperature, as well as in a delay of the arc velocity with respect to the gas flow velocity, allowing more gas to pass through the arc, and thus increasing the efficiency of the gliding arc for gas treatment applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000419253000001 Publication Date 2016-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 9 Open Access OpenAccess
Notes This work is financially supported by the Methusalem financing, by the Fund for Scientific Research Flanders (FWO) and by the IAP/7 (Inter-university Attraction Pole) program ‘Physical Chemistry of Plasma-Surface Interactions’ from the Belgian Federal Office for Science Policy (BELSPO). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. This work was also supported by the National Natural Science Foundation of China (Grant Nos. 11275021, 11575019). S R Sun thanks the financial support from the China Scholarship Council. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @ c:irua:138993 Serial 4337
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Author Kadu, A.; van Leeuwen, T.; Batenburg, K.J.
Title CoShaRP : a convex program for single-shot tomographic shape sensing Type A1 Journal article
Year 2021 Publication Inverse Problems Abbreviated Journal Inverse Probl
Volume 37 Issue 10 Pages 105005
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We introduce single-shot x-ray tomography that aims to estimate the target image from a single cone-beam projection measurement. This linear inverse problem is extremely under-determined since the measurements are far fewer than the number of unknowns. Moreover, it is more challenging than conventional tomography, where a sufficiently large number of projection angles forms the measurements, allowing for a simple inversion process. However, single-shot tomography becomes less severe if the target image is only composed of known shapes. This paper restricts analysis to target image function that can be decomposed into known compactly supported non-negative-valued functions termed shapes. Hence, the shape prior transforms a linear ill-posed image estimation problem to a non-linear problem of estimating the roto-translations of the shapes. We circumvent the non-linearity by using a dictionary of possible roto-translations of the shapes. We propose a convex program CoShaRP, to recover the dictionary coefficients successfully. CoShaRP relies on simplex-type constraints and can be solved quickly using a primal-dual algorithm. The numerical experiments show that CoShaRP recovers shape stably from moderately noisy measurements.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000691743700001 Publication Date 2021-07-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0266-5611 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.62 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 1.62
Call Number UA @ admin @ c:irua:181617 Serial 6859
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