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Author Aussems, D.U.B.; Bal, K. M.; Morgan, T.W.; van de Sanden, M.C.M.; Neyts, E.C.
Title Atomistic simulations of graphite etching at realistic time scales Type A1 Journal article
Year 2017 Publication Chemical science Abbreviated Journal Chem Sci
Volume 8 Issue 10 Pages 7160-7168
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Hydrogen–graphite interactions are relevant to a wide variety of applications, ranging from astrophysics to fusion devices and nano-electronics. In order to shed light on these interactions, atomistic simulation using Molecular Dynamics (MD) has been shown to be an invaluable tool. It suffers, however, from severe timescale

limitations. In this work we apply the recently developed Collective Variable-Driven Hyperdynamics (CVHD) method to hydrogen etching of graphite for varying inter-impact times up to a realistic value of 1 ms, which corresponds to a flux of 1020 m2 s1. The results show that the erosion yield, hydrogen surface coverage and species distribution are significantly affected by the time between impacts. This can be explained by the higher probability of C–C bond breaking due to the prolonged exposure to thermal stress and the subsequent transition from ion- to thermal-induced etching. This latter regime of thermal-induced etching – chemical erosion – is here accessed for the first time using atomistic simulations. In conclusion, this study demonstrates that accounting for long time-scales significantly affects ion bombardment simulations and should not be neglected in a wide range of conditions, in contrast to what is typically assumed.
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Language Wos 000411730500055 Publication Date 2017-08-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-6520 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.668 Times cited 3 Open Access OpenAccess
Notes DIFFER is part of the Netherlands Organisation for Scientic Research (NWO). K. M. B. is funded as a PhD fellow (aspirant) of the FWO-Flanders (Fund for Scientic Research-Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI. Approved Most recent IF: 8.668
Call Number PLASMANT @ plasmant @c:irua:145519 Serial 4707
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Author Bal, K.M.; Huygh, S.; Bogaerts, A.; Neyts, E.C.
Title Effect of plasma-induced surface charging on catalytic processes: application to CO2activation Type A1 Journal article
Year 2018 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 27 Issue 2 Pages 024001
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Understanding the nature and effect of the multitude of plasma–surface interactions in plasma catalysis is a crucial requirement for further process development and improvement. A particularly intriguing and rather unique property of a plasma-catalytic setup is the ability of the plasma to modify the electronic structure, and hence chemical properties, of the catalyst through charging, i.e. the absorption of excess electrons. In this work, we develop a quantum chemical model based on density functional theory to study excess negative surface charges in a heterogeneous catalyst exposed to a plasma. This method is specifically applied to investigate plasma-catalytic CO2 activation on supported M/Al2O3 (M=Ti, Ni, Cu) single atom catalysts. We find that (1) the presence of a negative surface charge dramatically improves the reductive power of the catalyst, strongly promoting the splitting of CO2 to CO and oxygen, and (2) the relative activity of the investigated transition metals is also changed upon charging, suggesting that controlled surface charging is a powerful additional parameter to tune catalyst activity and selectivity. These results strongly point to plasma-induced surface charging of the catalyst as an important factor contributing to the plasma-catalyst synergistic effects frequently reported for plasma catalysis.
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Language Wos 000424520100001 Publication Date 2018-02-07
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 19 Open Access OpenAccess
Notes KMB is funded as PhD fellow (aspirant) of the FWO-Flanders (Research Foundation—Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government— department EWI. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:149285 Serial 4813
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Author Bogaerts, A.; Neyts, E.C.
Title Plasma Technology: An Emerging Technology for Energy Storage Type A1 Journal article
Year 2018 Publication ACS energy letters Abbreviated Journal Acs Energy Lett
Volume 3 Issue 4 Pages 1013-1027
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma technology is gaining increasing interest for gas conversion applications, such as CO2 conversion into value-added chemicals or renewable fuels, and N2 fixation from the air, to be used for the production of small building blocks for, e.g., mineral fertilizers. Plasma is generated by electric power and can easily be switched on/off, making it, in principle, suitable for using intermittent renewable electricity. In this Perspective article, we explain why plasma might be promising for this application. We briefly present the most common types of plasma reactors with their characteristic features, illustrating why some plasma types exhibit better energy efficiency than others. We also highlight current research in the fields of CO2 conversion (including the combined conversion of CO2 with CH4, H2O, or H2) as well as N2 fixation (for NH3 or NOx synthesis). Finally, we discuss the major limitations and steps to be taken for further improvement.
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Publisher Place of Publication Editor
Language Wos 000430369600035 Publication Date 2018-04-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2380-8195 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 56 Open Access OpenAccess
Notes Universiteit Antwerpen, TOP research project 32249 ; Fonds Wetenschappelijk Onderzoek, G.0217.14N G.0254.14N G.0383.16N ; Approved Most recent IF: NA
Call Number PLASMANT @ plasmant @c:irua:150358 Serial 4919
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Author Razzokov, J.; Yusupov, M.; Vanuytsel, S.; Neyts, E.C.; Bogaerts, A.
Title Phosphatidylserine flip-flop induced by oxidation of the plasma membrane: a better insight by atomic scale modeling Type A1 Journal article
Year 2017 Publication Plasma processes and polymers Abbreviated Journal Plasma Process Polym
Volume 14 Issue 10 Pages 1700013
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We perform molecular dynamics simulations to study the flip-flop motion of phosphatidylserine (PS) across the plasma membrane upon increasing oxidation degree of the membrane. Our computational results show that an increase of the oxidation degree in the lipids leads to a decrease of the free energy barrier for translocation of PS through the membrane. In other words, oxidation of the lipids facilitates PS flip-flop motion across the membrane, because in native phospholipid bilayers this is only a “rare event” due to the high energy barriers for the translocation of PS. The present study provides an atomic-scale insight into the mechanisms of the PS flip-flop upon oxidation of lipids, as produced for example by cold atmospheric plasma, in living cells.
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Publisher Place of Publication Editor
Language Wos 000413045800010 Publication Date 2017-04-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1612-8850 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.846 Times cited 9 Open Access Not_Open_Access
Notes Fonds Wetenschappelijk Onderzoek, 1200216N ; Approved Most recent IF: 2.846
Call Number PLASMANT @ plasmant @c:irua:149567 Serial 4910
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Author Bal, K.M.; Neyts, E.C.
Title Modelling molecular adsorption on charged or polarized surfaces: a critical flaw in common approaches Type A1 Journal article
Year 2018 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 20 Issue 13 Pages 8456-8459
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A number of recent computational material design studies based on density functional theory (DFT) calculations have put forward a new class of materials with electrically switchable chemical characteristics that can be exploited in the development of tunable gas storage and electrocatalytic applications. We find systematic flaws in almost every computational study of gas adsorption on polarized or charged surfaces, stemming from an improper and unreproducible treatment of periodicity, leading to very large errors of up to 3 eV in some cases. Two simple corrective procedures that lead to consistent results are proposed, constituting a crucial course correction to the research in the field.
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Language Wos 000428779700007 Publication Date 2018-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 8 Open Access OpenAccess
Notes K. M. B. is funded as PhD fellow (aspirant) of the FWO-Flanders (Research Foundation – Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government – department EWI. Approved Most recent IF: 4.123
Call Number PLASMANT @ plasmant @c:irua:150357 Serial 4916
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Author Heyne, M.H.; de Marneffe, J.-F.; Nuytten, T.; Meersschaut, J.; Conard, T.; Caymax, M.; Radu, I.; Delabie, A.; Neyts, E.C.; De Gendt, S.
Title The conversion mechanism of amorphous silicon to stoichiometric WS2 Type A1 Journal article
Year 2018 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
Volume 6 Issue 15 Pages 4122-4130
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The deposition of ultra-thin tungsten films and their related 2D chalcogen compounds on large area dielectric substrates by gas phase reactions is challenging. The lack of nucleation sites complicates the adsorption of W-related precursors and subsequent sulfurization usually requires high temperatures. We propose here a technique in which a thin solid amorphous silicon film is used as reductant for the gas phase precursor WF6 leading to the conversion to metallic W. The selectivity of the W conversion towards the underlying dielectric surfaces is demonstrated. The role of the Si surface preparation, the conversion temperature, and Si thickness on the formation process is investigated. Further, the in situ conversion of the metallic tungsten into thin stoichiometric WS2 is achieved by a cyclic approach based on WF6 and H2S pulses at the moderate temperature of 450 1C, which is much lower than usual oxide sulfurization processes.
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Publisher Place of Publication Editor
Language Wos 000430538000036 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.256 Times cited 4 Open Access OpenAccess
Notes This work was supported throughout a strategic fundamental research grant for M. H. by the agency Flanders innovation & entrepreneurship (VLAIO). Approved Most recent IF: 5.256
Call Number PLASMANT @ plasmant @c:irua:150968 Serial 4921
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Author Aussems, D.U.B.; Bal, K.M.; Morgan, T.W.; van de Sanden, M.C.M.; Neyts, E.C.
Title Mechanisms of elementary hydrogen ion-surface interactions during multilayer graphene etching at high surface temperature as a function of flux Type A1 Journal article
Year 2018 Publication Carbon Abbreviated Journal Carbon
Volume 137 Issue Pages 527-532
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In order to optimize the plasma-synthesis and modification process of carbon nanomaterials for applications such as nanoelectronics and energy storage, a deeper understanding of fundamental hydrogengraphite/graphene interactions is required. Atomistic simulations by Molecular Dynamics have proven to be indispensable to illuminate these phenomena. However, severe time-scale limitations restrict them to very fast processes such as reflection, while slow thermal processes such as surface diffusion and molecular desorption are commonly inaccessible. In this work, we could however reach these thermal processes for the first time at time-scales and surface temperatures (1000 K) similar to high-flux plasma exposure experiments during the simulation of multilayer graphene etching by 5 eV H ions. This was achieved by applying the Collective Variable-Driven Hyperdynamics biasing technique, which extended the inter-impact time over a range of six orders of magnitude, down to a more realistic ion-flux of 1023m2s1. The results show that this not only causes a strong shift from predominant ion-to thermally induced interactions, but also significantly affects the hydrogen uptake and surface evolution. This study thus elucidates H ion-graphite/graphene interaction mechanisms and stresses the importance of including long time-scales in atomistic simulations at high surface temperatures to understand the dynamics of the ion-surface system.
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Publisher Place of Publication Editor
Language Wos 000440661700056 Publication Date 2018-05-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited 4 Open Access Not_Open_Access: Available from 25.05.2020
Notes DIFFER is part of the Netherlands Organisation for Scientific Research (NWO). K.M.B. is funded as PhD fellow (aspirant) of the FWO-Flanders (Fund for Scientific Research-Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government e department EWI. Approved Most recent IF: 6.337
Call Number PLASMANT @ plasmant @c:irua:152172 Serial 4993
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Author Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A.
Title Enhancement of plasma generation in catalyst pores with different shapes Type A1 Journal article
Year 2018 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 27 Issue 5 Pages 055008
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma generation inside catalyst pores is of utmost importance for plasma catalysis, as the existence of plasma species inside the pores affects the active surface area of the catalyst available to the plasma species for catalytic reactions. In this paper, the electric field enhancement, and thus the plasma production inside catalyst pores with different pore shapes is studied with a two-dimensional fluid model. The results indicate that the electric field will be significantly enhanced near tip-like structures. In a conical pore with small opening, the strongest electric field appears at the opening and bottom corners of the pore, giving rise to a prominent ionization rate throughout the pore. For a cylindrical pore, the electric field is only enhanced at the bottom corners of the pore, with lower absolute value, and thus the ionization rate inside the pore is only slightly enhanced. Finally, in a conical pore with large opening, the electric field is characterized by a maximum at the bottom of the pore, yielding a similar behavior for the ionization rate. These results demonstrate that the shape of the pore has a significantly influence on the electric field enhancement, and thus modifies the plasma properties.
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Publisher Place of Publication Editor
Language Wos 000432351700002 Publication Date 2018-05-15
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 11 Open Access OpenAccess
Notes This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant No. G.0217.14N) and the Fundamental Research Funds for the Central Universities (Grant No. DUT17LK52). Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:151546 Serial 4998
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Author Huygh, S.; Bogaerts, A.; Bal, K.M.; Neyts, E.C.
Title High Coke Resistance of a TiO2Anatase (001) Catalyst Surface during Dry Reforming of Methane Type A1 Journal Article
Year 2018 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume 122 Issue 17 Pages 9389-9396
Keywords A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract The resistance of a TiO2 anatase (001) surface to coke formation was studied in the context of dry reforming of methane using density functional theory (DFT) calculations. As carbon atoms act as precursors for coke formation, the resistance to coke formation can be measured by the carbon coverage of the surface. This is related to the stability of different CHx (x = 0−3) species and their rate of hydrogenation and dehydrogenation on the TiO2 surface. Therefore, we studied the reaction mechanisms and their corresponding rates as a function of the temperature for the dehydrogenation of the species on the surface. We found that the stabilities of C and CH are significantly lower than those of CH3 and CH2. The hydrogenation rates of the different species are significantly higher than the dehydrogenation rates in a temperature range of 300−1000 K. Furthermore, we found that dehydrogenation of CH3, CH2, and CH will only occur at appreciable rates starting from 600, 900, and 900 K, respectively. On the basis of these results, it is clear that the anatase (001) surface has a high coke resistance, and it is thus not likely that the surface will become poisoned by coke during dry reforming of methane. As the rate limiting step in dry reforming is the dissociative adsorption of CH4, we studied an alternative approach to thermal catalysis. We found that the temperature threshold for dry reforming is at least 700 K. This threshold temperature may be lowered by the use of plasma-catalysis, where the appreciable rates of adsorption of plasma-generated CHx radicals result in bypassing the rate limiting step of the reaction.
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Publisher Place of Publication Editor
Language Wos 000431723700014 Publication Date 2018-05-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 1 Open Access OpenAccess
Notes Federaal Wetenschapsbeleid, IAP/7 ; Fonds Wetenschappelijk Onderzoek, G.0217.14N ; Onderzoeksfonds, Universiteit Antwerpen, 32249 ; Approved Most recent IF: 4.536
Call Number PLASMANT @ plasmant @c:irua:151529c:irua:152816 Serial 5000
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Author Amini, M.N.; Altantzis, T.; Lobato, I.; Grzelczak, M.; Sánchez-Iglesias, A.; Van Aert, S.; Liz-Marzán, L.M.; Partoens, B.; Bals, S.; Neyts, E.C.
Title Understanding the Effect of Iodide Ions on the Morphology of Gold Nanorods Type A1 Journal article
Year 2018 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char
Volume 35 Issue 35 Pages 1800051
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The presence of iodide ions during the growth of gold nanorods strongly affects the shape of the final products, which is proposed to be due to selective iodide adsorption on certain crystallographic facets. Therefore, a detailed structural and morphological characterization of the starting rods is crucial toward understanding this effect. Electron tomography is used to determine the crystallographic indices of the lateral facets of gold nanorods, as well as those present at the tips. Based on this information, density functional theory calculations are used to determine the surface and interface energies of the observed facets and provide insight into the relationship between the amount of iodide ions in the growth solution and the final morphology of anisotropic gold nanoparticles.
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Language Wos 000441893400002 Publication Date 2018-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0934-0866 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.474 Times cited 6 Open Access OpenAccess
Notes This work was supported by the European Research Council (grant 335078 COLOURATOM to S.B.). T.A., S.V.A. S.B. and E.C.N., acknowledge funding from the Research Foundation Flanders (FWO, Belgium), through project funding (G.0218.14N and G.0369.15N) and a postdoctoral grant to T.A. L.M.L.-M. and M.G. acknowledge funding from the Spanish Ministerio de Economía y Competitividad (grant MAT2013-46101-R). Mozhgan N. Amini and Thomas Altantzis contributed equally to this work. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ecas_sara Approved Most recent IF: 4.474
Call Number EMAT @ emat @c:irua:152998UA @ admin @ c:irua:152998 Serial 5010
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Author Bal, K.M.; Neyts, E.C.
Title Overcoming Old Scaling Relations and Establishing New Correlations in Catalytic Surface Chemistry: Combined Effect of Charging and Doping Type A1 Journal article
Year 2019 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 123 Issue 10 Pages 6141-6147
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Optimization of catalytic materials for a given application is greatly constrained by linear scaling relations. Recently, however, it has been demonstrated that it is possible to reversibly modulate the chemisorption of molecules on nanomaterials by charging (i.e., injection or removal of electrons) and hence reversibly and selectively modify catalytic activity beyond structure−activity correlations. The fundamental physical relation between the properties of the material, the charging process, and the chemisorption energy, however, remains unclear, and a systematic exploration and optimization of charge-switchable sorbent materials is not yet possible. Using hybrid DFT calculations of CO2 chemisorption on hexagonal boron nitride nanosheets with several types of defects and dopants, we here reveal the existence of fundamental correlations between the electron affinity of a material and charge-induced chemisorption, show how defect engineering can be used to modulate the strength and efficiency of the adsorption process, and demonstrate that excess electrons stabilize many topological defects. We then show how these insights could be exploited in the development of new electrocatalytic materials and the synthesis of doped nanomaterials. Moreover, we demonstrate that calculated chemical properties of charged materials are highly sensitive to the employed computational methodology because of the self-interaction error, which underlines the theoretical challenge posed by such systems.
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Publisher Place of Publication Editor
Language Wos 000461537400035 Publication Date 2019-03-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 5 Open Access Not_Open_Access: Available from 21.02.2020
Notes Fonds Wetenschappelijk Onderzoek, 11V8915N ; Approved Most recent IF: 4.536
Call Number PLASMANT @ plasmant @UA @ admin @ c:irua:158117 Serial 5160
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Author Khalilov, U.; Vets, C.; Neyts, E.C.
Title Molecular evidence for feedstock-dependent nucleation mechanisms of CNTs Type A1 Journal article
Year 2019 Publication Nanoscale Horizons Abbreviated Journal Nanoscale Horiz.
Volume 4 Issue 3 Pages 674-682
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Atomic scale simulations have been shown to be a powerful tool for elucidating the growth mechanisms of carbon nanotubes. The growth picture is however not entirely clear yet due to the gap between current simulations and real experiments. We here simulate for the first time the nucleation and subsequent growth of single-wall carbon nanotubes (SWNTs) from oxygen-containing hydrocarbon feedstocks using the hybrid Molecular Dynamics/Monte Carlo technique. The underlying nucleation mechanisms of Ni-catalysed SWNT growth are discussed in detail. Specifically, we find that as a function of the feedstock, different carbon fractions may emerge as the main growth species, due to a competition between the feedstock decomposition, its rehydroxylation and its contribution to etching of the growing SWNT. This study provides a further understanding of the feedstock effects in SWNT growth in comparison with available experimental evidence as well as with<italic>ab initio</italic>and other simulation data, thereby reducing the simulation–experiment gap.
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Publisher Place of Publication Editor
Language Wos 000471816500011 Publication Date 2019-01-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2055-6756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 1 Open Access Not_Open_Access: Available from 03.01.2020
Notes Fonds Wetenschappelijk Onderzoek, 12M1318N 1S22516N ; The authors gratefully acknowledge financial support from the Research Foundation Flanders (FWO), Belgium (Grant numbers 12M1318N and 1S22516N). The work was carried out in part using the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Centre VSC, funded by FWO and the Flemish Government (Department EWI). We thank Prof. A. C. T. van Duin for sharing the reax-code and forcefield parameters. Approved Most recent IF: NA
Call Number PLASMANT @ plasmant @UA @ admin @ c:irua:159658 Serial 5169
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Author Khalilov, U.; Vets, C.; Neyts, E.C.
Title Catalyzed growth of encapsulated carbyne Type A1 Journal article
Year 2019 Publication Carbon Abbreviated Journal Carbon
Volume 153 Issue Pages 1-5
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Carbyne is a novel material of current interest in nanotechnology. As is typically the case for nanomaterials, the growth process determines the resulting properties. While endohedral carbyne has been successfully synthesized, its catalyst and feedstock-dependent growth mechanism is still elusive. We here study the nucleation and growth mechanism of different carbon chains in a Ni-containing double walled carbon nanotube using classical molecular dynamics simulations and first-principles calculations. We find that the understanding the competitive role of the metal catalyst and the hydrocarbon is important to control the growth of 1-dimensional carbon chains, including Ni or H-terminated carbyne. Also, we find that the electronic property of the Ni-terminated carbyne can be tuned by steering the H concentration along the chain. These results suggest catalyst-containing carbon nanotubes as a possible synthesis route for carbyne formation.
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Publisher Place of Publication Editor
Language Wos 000485054200001 Publication Date 2019-07-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited Open Access Not_Open_Access
Notes Fund of Scientific Research Flanders (FWO), Belgium, 12M1318N 1S22516N ; Flemish Supercomputer Centre VSC; Hercules Foundation; Flemish Government; University of Antwerp; The authors gratefully acknowledge the financial support from the Fund of Scientific Research Flanders (FWO), Belgium, Grant numbers 12M1318N and 1S22516N. 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 Centre VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 6.337
Call Number PLASMANT @ plasmant @c:irua:160695 Serial 5187
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Author Bal, K.M.; Bogaerts, A.; Neyts, E.C.
Title Ensemble-Based Molecular Simulation of Chemical Reactions under Vibrational Nonequilibrium Type A1 Journal article
Year 2020 Publication Journal Of Physical Chemistry Letters Abbreviated Journal J Phys Chem Lett
Volume 11 Issue 2 Pages 401-406
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We present an approach to incorporate the effect of vibrational nonequilibrium in molecular dynamics (MD) simulations. A perturbed canonical ensemble, in which selected modes are excited to higher temperature while all others remain equilibrated at low temperature, is simulated by applying a specifically tailored bias potential. Our method can be readily applied to any (classical or quantum mechanical) MD setup at virtually no additional computational cost and allows the study of reactions of vibrationally excited molecules in nonequilibrium environments such as plasmas. In combination with enhanced sampling methods, the vibrational efficacy and mode selectivity of vibrationally stimulated reactions can then be quantified in terms of chemically relevant observables, such as reaction rates and apparent free energy barriers. We first validate our method for the prototypical hydrogen exchange reaction and then show how it can capture the effect of vibrational excitation on a symmetric SN2 reaction and radical addition on CO2.
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Publisher Place of Publication Editor
Language Wos 000508473400008 Publication Date 2020-01-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1948-7185 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.7 Times cited Open Access
Notes Universiteit Antwerpen; Fonds Wetenschappelijk Onderzoek, 12ZI420N ; Departement Economie, Wetenschap en Innovatie van de Vlaamse Overheid; K.M.B. was funded as a junior postdoctoral fellow of the FWO (Research Foundation − Flanders), Grant 12ZI420N, and through a TOP-BOF research project of the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government− department EWI. Approved Most recent IF: 5.7; 2020 IF: 9.353
Call Number PLASMANT @ plasmant @c:irua:165587 Serial 5442
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Author Fukuhara, S.; Bal, K.M.; Neyts, E.C.; Shibuta, Y.
Title Accelerated molecular dynamics simulation of large systems with parallel collective variable-driven hyperdynamics Type A1 Journal article
Year 2020 Publication Computational Materials Science Abbreviated Journal Comp Mater Sci
Volume 177 Issue Pages 109581
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The limitation in time and length scale is a major issue of molecular dynamics (MD) simulation. Although several methods have been developed to extend the MD time scale, their performance usually deteriorates with increasing system size. Therefore, an acceleration method which is applicable to large systems is required to bridge the gap between the MD simulations and target phenomena. In this study, an accelerated MD method for large system is developed based on the collective variable-driven hyperdynamics (CVHD) method [K.M. Bal and E.C. Neyts, 2015]. The key idea is to run CVHD in parallel with rate control and accelerate multiple possible events simultaneously. Using this novel method, carbon diffusion in bcc-iron bicrystal with grain boundary is examined as an application for practical materials. Carbon atoms reaching at the grain boundary are trapped whereas carbon atoms in the bulk region diffuse randomly, and both dynamic regimes can be simultaneously accelerated with the parallel CVHD technique.
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Publisher Place of Publication Editor
Language Wos 000519576300001 Publication Date 2020-02-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-0256 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.3 Times cited Open Access
Notes JSPS, J22727 ; Japan Society for the Promotion of Science; This work was supported by Grant-in-Aid for Scientific Research (B) (No.19H02415) and Grant-in-Aid for JSPS Research Fellow (No.18J22727) from Japan Society for the Promotion of Science (JSPS), Japan. S.F. was supported by JSPS through the Program for Leading Graduate Schools (MERIT). Data availability The data required to reproduce these findings are available from the corresponding authors upon reasonable request. Approved Most recent IF: 3.3; 2020 IF: 2.292
Call Number PLASMANT @ plasmant @c:irua:166773 Serial 6333
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Author Jafarzadeh, A.; Bal, K.M.; Bogaerts, A.; Neyts, E.C.
Title Activation of CO2on Copper Surfaces: The Synergy between Electric Field, Surface Morphology, and Excess Electrons Type A1 Journal article
Year 2020 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume 124 Issue 12 Pages 6747-6755
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this work, we use density functional theory calculations to study the combined effect of external electric fields, surface morphology, and surface charge on CO2 activation over Cu(111), Cu(211), Cu(110), and Cu(001) surfaces. We observe that the binding energy of the CO2 molecule on Cu surfaces increases significantly upon increasing the applied electric field strength. In addition, rougher surfaces respond more effectively to the presence of the external electric field toward facilitating the formation of a carbonate-like CO2 structure and the transformation of the most stable adsorption mode from physisorption to chemisorption. The presence of surface charges further strengthens the electric field effect and consequently causes an improved bending of the CO2 molecule and C−O bond length elongation. On the other hand, a net charge in the absence of an externally applied electric field shows only a marginal effect on CO2 binding. The chemisorbed CO2 is more stable and further activated when the effects of an external electric field, rough surface, and surface charge are combined. These results can help to elucidate the underlying factors that control CO2 activation in heterogeneous and plasma catalysis, as well as in electrochemical processes.
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Publisher Place of Publication Editor
Language Wos 000526396900030 Publication Date 2020-03-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited Open Access
Notes Bijzonder Onderzoeksfonds, 32249 ; The financial support from the TOP research project of the Research Fund of the University of Antwerp (grant ID: 32249) is highly acknowledged by the authors. The computational resources used in this study were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Governmentdepartment EWI. Approved Most recent IF: 3.7; 2020 IF: 4.536
Call Number PLASMANT @ plasmant @c:irua:168606 Serial 6361
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Author Engelmann, Y.; Mehta, P.; Neyts, E.C.; Schneider, W.F.; Bogaerts, A.
Title Predicted Influence of Plasma Activation on Nonoxidative Coupling of Methane on Transition Metal Catalysts Type A1 Journal article
Year 2020 Publication Acs Sustainable Chemistry & Engineering Abbreviated Journal Acs Sustain Chem Eng
Volume 8 Issue 15 Pages 6043-6054
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Movement Antwerp (MOVANT)
Abstract The combination of catalysis and nonthermal plasma holds promise for enabling difficult chemical conversions. The possible synergy between both depends strongly on the nature of the reactive plasma species and the catalyst material. In this paper, we show how vibrationally excited species and plasma-generated radicals interact with transition metal catalysts and how changing the catalyst material can improve the conversion rates and product selectivity. We developed a microkinetic model to investigate the impact of vibrational excitations and plasma-generated radicals on the nonoxidative coupling of methane over transition metal surfaces. We predict a significant increase in ethylene formation for vibrationally excited methane. Plasma-generated radicals have a stronger impact on the turnover frequencies with high selectivity toward ethylene on noble catalysts and mixed selectivity on non-noble catalysts. In general, we show how the optimal catalyst material depends on the desired products as well as the plasma conditions.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000526884000025 Publication Date 2020-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2168-0485 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.4 Times cited Open Access
Notes Herculesstichting; University of Notre Dame; Universiteit Antwerpen; Division of Engineering Education and Centers, EEC-1647722 ; We would like to thank Tom Butterworth for his work on methane vibrational distribution functions (VDF) and for sharing his thoughts and experiences on this matter, specifically regarding the VDF of the degenerate modes of methane. We ACS Sustainable Chemistry & Engineering pubs.acs.org/journal/ascecg Research Article https://dx.doi.org/10.1021/acssuschemeng.0c00906 ACS Sustainable Chem. Eng. 2020, 8, 6043−6054 6052 also acknowledge financial support from the DOC-PRO3 and the TOP-BOF projects of the University of Antwerp. 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. Support for W.F.S. was provided by the National Science Foundation under cooperative agreement no. EEC-1647722, an Engineering Research Center for the Innovative and Strategic Transformation of Alkane Resources (CISTAR). P.M. acknowledges support through the Eilers Graduate Fellowship of the University of Notre Dame. Approved Most recent IF: 8.4; 2020 IF: 5.951
Call Number PLASMANT @ plasmant @c:irua:169228 Serial 6366
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Author Khalilov, U.; Neyts, E.C.
Title Mechanisms of selective nanocarbon synthesis inside carbon nanotubes Type A1 Journal article
Year 2021 Publication Carbon Abbreviated Journal Carbon
Volume 171 Issue Pages 72-78
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The possibility of confinement effects inside a carbon nanotube provides new application opportunities, e.g., growth of novel carbon nanostructures. However, the understanding the precise role of catalystfeedstock in the nanostructure synthesis is still elusive. In our simulation-based study, we investigate the Ni-catalyzed growth mechanism of encapsulated carbon nanostructures, viz. double-wall carbon nanotube and graphene nanoribbon, from carbon and hydrocarbon growth precursors, respectively. Specifically, we find that the tube and ribbon growth is determined by a catalyst-vs-feedstock competition effect. We compare our results, i.e., growth mechanism and structure morphology with all available theoretical and experimental data. Our calculations show that all encapsulated nanostructures contain metal (catalyst) atoms and such structures are less stable than their pure counterparts. Therefore, we study the purification mechanism of these structures. In general, this study opens a possible route to the controllable synthesis of tubular and planar carbon nanostructures for today’s nanotechnology.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000598371500009 Publication Date 2020-09-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record
Impact Factor 6.337 Times cited Open Access OpenAccess
Notes Fund of Scientific Research Flanders, 12M1318N ; Universiteit Antwerpen; Flemish Supercomputer Centre; Hercules Foundation; Flemish Government; The authors gratefully acknowledge the financial support from the Fund of Scientific Research Flanders (FWO), Belgium, Grant number 12M1318N. The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Centre (VSC), funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA, Belgium. Approved Most recent IF: 6.337
Call Number PLASMANT @ plasmant @c:irua:172459 Serial 6414
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Author Bal, K.M.; Fukuhara, S.; Shibuta, Y.; Neyts, E.C.
Title Free energy barriers from biased molecular dynamics simulations Type A1 Journal article
Year 2020 Publication Journal Of Chemical Physics Abbreviated Journal J Chem Phys
Volume 153 Issue 11 Pages 114118
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Atomistic simulation methods for the quantification of free energies are in wide use. These methods operate by sampling the probability density of a system along a small set of suitable collective variables (CVs), which is, in turn, expressed in the form of a free energy surface (FES). This definition of the FES can capture the relative stability of metastable states but not that of the transition state because the barrier height is not invariant to the choice of CVs. Free energy barriers therefore cannot be consistently computed from the FES. Here, we present a simple approach to calculate the gauge correction necessary to eliminate this inconsistency. Using our procedure, the standard FES as well as its gauge-corrected counterpart can be obtained by reweighing the same simulated trajectory at little additional cost. We apply the method to a number of systems—a particle solvated in a Lennard-Jones fluid, a Diels–Alder reaction, and crystallization of liquid sodium—to demonstrate its ability to produce consistent free energy barriers that correctly capture the kinetics of chemical or physical transformations, and discuss the additional demands it puts on the chosen CVs. Because the FES can be converged at relatively short (sub-ns) time scales, a free energy-based description of reaction kinetics is a particularly attractive option to study chemical processes at more expensive quantum mechanical levels of theory.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000574665600004 Publication Date 2020-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.4 Times cited Open Access
Notes Japan Society for the Promotion of Science, 19H02415 18J22727 ; Fonds Wetenschappelijk Onderzoek, 12ZI420N ; This work was supported, in part, by a Grant-in-Aid for Scientific Research (B) (Grant No. 19H02415) and Grant-in-Aid for a JSPS Research Fellow (Grant No. 18J22727) from the Japan Society for the Promotion of Science (JSPS), Japan. K.M.B. was funded as a junior postdoctoral fellow of the FWO (Research Foundation – Flanders), Grant No. 12ZI420N. S.F. was supported by JSPS through the Program for Leading Graduate Schools (MERIT). The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government. The authors are grateful to Pablo Piaggi for making the pair entropy CV code publicly available. Approved Most recent IF: 4.4; 2020 IF: 2.965
Call Number PLASMANT @ plasmant @c:irua:172456 Serial 6420
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Author Fukuhara, S.; Bal, K.M.; Neyts, E.C.; Shibuta, Y.
Title Entropic and enthalpic factors determining the thermodynamics and kinetics of carbon segregation from transition metal nanoparticles Type A1 Journal article
Year 2021 Publication Carbon Abbreviated Journal Carbon
Volume 171 Issue Pages 806-813
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The free energy surface (FES) for carbon segregation from nickel nanoparticles is obtained from advanced molecular dynamics simulations. A suitable reaction coordinate is developed that can distinguish dissolved carbon atoms from segregated dimers, chains and junctions on the nanoparticle surface. Because of the typically long segregation time scale (up to ms), metadynamics simulations along the developed reaction coordinate are used to construct FES over a wide range of temperatures and carbon concentrations. The FES revealed the relative stability of different stages in the segregation process, and free energy barriers and rates of the individual steps could then be calculated and decomposed into enthalpic and entropic contributions. As the carbon concentration in the nickel nanoparticle increases, segregated carbon becomes more stable in terms of both enthalpy and entropy. The activation free energy of the reaction also decreases with the increase of carbon concentration, which can be mainly attributed to entropic effects. These insights and the methodology developed to obtain them improve our understanding of carbon segregation process across materials science in general, and the nucleation and growth of carbon nanotube in particular.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000598371500084 Publication Date 2020-09-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited Open Access OpenAccess
Notes Scientific Research, 19H02415 ; JSPS, 18J22727 ; Japan Society for the Promotion of Science; JSPS; JSPS; FWO; Research Foundation; Flanders, 12ZI420N ; This work was supported by Grant-in-Aid for Scientific Research (B) (No.19H02415) and Grant-in-Aid for JSPS Research Fellow (No.18J22727) from Japan Society for the Promotion of Science (JSPS), Japan. S.F. was supported by JSPS through the Program for 812 Approved Most recent IF: 6.337
Call Number PLASMANT @ plasmant @c:irua:172452 Serial 6421
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Author Marinov, D.; de Marneffe, J.-F.; Smets, Q.; Arutchelvan, G.; Bal, K.M.; Voronina, E.; Rakhimova, T.; Mankelevich, Y.; El Kazzi, S.; Nalin Mehta, A.; Wyndaele, P.-J.; Heyne, M.H.; Zhang, J.; With, P.C.; Banerjee, S.; Neyts, E.C.; Asselberghs, I.; Lin, D.; De Gendt, S.
Title Reactive plasma cleaning and restoration of transition metal dichalcogenide monolayers Type A1 Journal article
Year 2021 Publication npj 2D Materials and Applications Abbreviated Journal npj 2D Mater Appl
Volume 5 Issue 1 Pages 17
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The cleaning of two-dimensional (2D) materials is an essential step in the fabrication of future devices, leveraging their unique physical, optical, and chemical properties. Part of these emerging 2D materials are transition metal dichalcogenides (TMDs). So far there is limited understanding of the cleaning of “monolayer” TMD materials. In this study, we report on the use of downstream H<sub>2</sub>plasma to clean the surface of monolayer WS<sub>2</sub>grown by MOCVD. We demonstrate that high-temperature processing is essential, allowing to maximize the removal rate of polymers and to mitigate damage caused to the WS<sub>2</sub>in the form of sulfur vacancies. We show that low temperature in situ carbonyl sulfide (OCS) soak is an efficient way to resulfurize the material, besides high-temperature H<sub>2</sub>S annealing. The cleaning processes and mechanisms elucidated in this work are tested on back-gated field-effect transistors, confirming that transport properties of WS<sub>2</sub>devices can be maintained by the combination of H<sub>2</sub>plasma cleaning and OCS restoration. The low-damage plasma cleaning based on H<sub>2</sub>and OCS is very reproducible, fast (completed in a few minutes) and uses a 300 mm industrial plasma etch system qualified for standard semiconductor pilot production. This process is, therefore, expected to enable the industrial scale-up of 2D-based devices, co-integrated with silicon technology.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000613258900001 Publication Date 2021-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-7132 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Daniil Marinov has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 752164. Ekaterina Voronina, Yuri Mankelevitch, and Tatyana Rakhimova are thankful to the Russian Science Foundation (RSF) for financial support (Grant No. 16-12-10361). This study was carried out using the equipment of the shared research facilities of high-performance computing resources at Lomonosov Moscow State University and the computational resources and services of the HPC core facility CalcUA of the University of Antwerp, and VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government. Patrick With gratefully acknowledges imec’s CTO office for financial support during his stay at imec. The authors thank Mr. Surajit Sutar (imec) for his help during sample electrical characterization, and Patrick Verdonck for lab processing. Jean-François de Marneffe thank Prof. Simone Napolitano from the Free University of Brussels for useful discussions on irreversibly adsorbed polymer layers, and Cédric Huyghebaert (imec) for his continuous support in the framework of the Graphene FET Flagship core project. All authors acknowledge the support of imec’s pilot line and materials characterization and analysis (MCA) group, namely Jonathan Ludwig, Stefanie Sergeant, Thomas Nuytten, Olivier Richard, and Thierry Conard. Finally, Daniil Marinov thank Mikhail Krishtab (imec/KU Leuven) for his help in selecting the optimal plasma etch system for this work. Part of this project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 649953. Approved Most recent IF: NA
Call Number PLASMANT @ plasmant @c:irua:175871 Serial 6671
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Author Yi, Y.; Wang, X.; Jafarzadeh, A.; Wang, L.; Liu, P.; He, B.; Yan, J.; Zhang, R.; Zhang, H.; Liu, X.; Guo, H.; Neyts, E.C.; Bogaerts, A.
Title Plasma-Catalytic Ammonia Reforming of Methane over Cu-Based Catalysts for the Production of HCN and H2at Reduced Temperature Type A1 Journal article
Year 2021 Publication Acs Catalysis Abbreviated Journal Acs Catal
Volume 11 Issue 3 Pages 1765-1773
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Industrial production of HCN from NH3 and CH4 not only uses precious Pt or Pt−Rh catalysts but also requires extremely high temperatures (∼1600 K). From an energetic, operational, and safety perspective, a drastic decrease in temperature is highly desirable. Here, we report ammonia reforming of methane for the production of HCN and H2 at 673 K by the combination of CH4/NH3 plasma and a supported Cu/silicalite-1 catalyst. 30% CH4 conversion has been achieved with 79% HCN selectivity. Catalyst characterization and plasma diagnostics reveal that the excellent reaction performance is attributed to metallic Cu active sites. In addition, we propose a possible reaction pathway, viz. E-R reactions with N, NH, NH2, and CH radicals produced in the plasma, for the production of HCN, based on density functional theory calculations. Importantly, the Cu/silicalite-1 catalyst costs less than 5% of the commercial Pt mesh catalyst.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000618540300057 Publication Date 2021-02-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2155-5435 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 10.614 Times cited Open Access OpenAccess
Notes Universiteit Antwerpen, 32249 ; China Postdoctoral Science Foundation, 2015M580220 2016T90217 ; PetroChina Innovation Foundation, 2018D-5007-0501 ; National Natural Science Foundation of China, 21503032 ; We acknowledge financial support from the National Natural Science Foundation of China [21503032], the China Postdoctoral Science Foundation [grant numbers 2015M580220 and 2016T90217, 2016], the PetroChina Innovation Foundation [2018D-5007-0501], and the TOP research project of the Research Fund of the University of Antwerp [grant ID 32249]. Approved Most recent IF: 10.614
Call Number PLASMANT @ plasmant @c:irua:175880 Serial 6675
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Author Berdiyorov, G.R.; Khalilov, U.; Hamoudi, H.; Neyts, E.C.
Title Effect of chemical modification on electronic transport properties of carbyne Type A1 Journal article
Year 2021 Publication Journal Of Computational Electronics Abbreviated Journal J Comput Electron
Volume Issue Pages
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Using density functional theory in combination with the Green’s functional formalism, we study the effect of surface functionalization on the electronic transport properties of 1D carbon allotrope—carbyne. We found that both hydrogenation and fluorination result in structural changes and semiconducting to metallic transition. Consequently, the current in the functionalization systems increases significantly due to strong delocalization of electronic states along the carbon chain. We also study the electronic transport in partially hydrogenated carbyne and interface structures consisting of pristine and functionalized carbyne. In the latter case, current rectification is obtained in the system with rectification ratio up to 50%. These findings can be useful for developing carbyne-based structures with tunable electronic transport properties.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000617664900001 Publication Date 2021-02-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1569-8025 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.526 Times cited Open Access OpenAccess
Notes Computational resources were provided by the research computing facilities of Qatar Environment and Energy Research Institute. Calculations are also conducted using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Centre VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. U. Khalilov gratefully acknowledges financial support from the Fund of Scientific Research Flanders (FWO), Belgium, Grant number 12M1315N. Approved Most recent IF: 1.526
Call Number PLASMANT @ plasmant @c:irua:176169 Serial 6708
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Author Izadi, M.E.; Bal, K.M.; Maghari, A.; Neyts, E.C.
Title Reaction mechanisms of C(3PJ) and C+(2PJ) with benzene in the interstellar medium from quantum mechanical molecular dynamics simulations Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 7 Pages 4205-4216
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract While spectroscopic data on small hydrocarbons in interstellar media in combination with crossed molecular beam (CMB) experiments have provided a wealth of information on astrochemically relevant species, much of the underlying mechanistic pathways of their formation remain elusive. Therefore, in this work, the chemical reaction mechanisms of C(<sup>3</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>and C<sup>+</sup>(<sup>2</sup>P) + C<sub>6</sub>H<sub>6</sub>systems using the quantum mechanical molecular dynamics (QMMD) technique at the PBE0-D3(BJ) level of theory is investigated, mimicking a CMB experiment. Both the dynamics of the reactions as well as the electronic structure for the purpose of the reaction network are evaluated. The method is validated for the first reaction by comparison to the available experimental data. The reaction scheme for the C(<sup>3</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>system covers the literature data,<italic>e.g.</italic>the major products are the 1,2-didehydrocycloheptatrienyl radical (C<sub>7</sub>H<sub>5</sub>) and benzocyclopropenyl radical (C<sub>6</sub>H<sub>5</sub>–CH), and it reveals the existence of less common pathways for the first time. The chemistry of the C<sup>+</sup>(<sup>2</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>system is found to be much richer, and we have found that this is because of more exothermic reactions in this system in comparison to those in the C(<sup>3</sup>P<sub>J</sub>) + C<sub>6</sub>H<sub>6</sub>system. Moreover, using the QMMD simulation, a number of reaction paths have been revealed that produce three distinct classes of reaction products with different ring sizes. All in all, at all the collision energies and orientations, the major product is the heptagon molecular ion for the ionic system. It is also revealed that the collision orientation has a dominant effect on the reaction products in both systems, while the collision energy mostly affects the charged system. These simulations both prove the applicability of this approach to simulate crossed molecular beams, and provide fundamental information on reactions relevant for the interstellar medium.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000621595300016 Publication Date 2021-01-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited Open Access OpenAccess
Notes Fonds Wetenschappelijk Onderzoek, 12ZI420N ; Ministry of Science Research and Technology; Universiteit Antwerpen; The financial support from the Iran Ministry of Science, Research and Technology and PLASMANT Research Group University of Antwerp is highly acknowledged by the authors. K.M.B. was funded as a junior postdoctoral fellow of the FWO (Research Foundation – Flanders), Grant 12ZI420N. The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government. Approved Most recent IF: 4.123
Call Number PLASMANT @ plasmant @c:irua:176672 Serial 6742
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Author Bal, K.M.; Neyts, E.C.
Title Quantifying the impact of vibrational nonequilibrium in plasma catalysis: insights from a molecular dynamics model of dissociative chemisorption Type A1 Journal Article;plasma catalysis
Year 2021 Publication Journal Of Physics D-Applied Physics Abbreviated Journal J Phys D Appl Phys
Volume 54 Issue 39 Pages 394004
Keywords A1 Journal Article;plasma catalysis; vibrational nonequilibrium; dissociative chemisorption; free energy barriers; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract The rate, selectivity and efficiency of plasma-based conversion processes is strongly affected by nonequilibrium phenomena. High concentrations of vibrationally excited molecules are such a plasma-induced effect. It is frequently assumed that vibrationally excited molecules are important in plasma catalysis because their presence lowers the apparent activation energy of dissociative chemisorption reactions and thus increases the conversion rate. A detailed atomic-level understanding of vibrationally stimulated catalytic reactions in the context of plasma catalysis is however lacking. Here, we couple a recently developed statistical model of a plasma-induced vibrational nonequilibrium to molecular dynamics simulations, enhanced sampling methods, and machine learning techniques. We quantify the impact of a vibrational nonequilibrium on the dissociative chemisorption barrier of H2 and CH4 on nickel catalysts over a wide range of vibrational temperatures. We investigate the effect of surface structure and compare the role of different vibrational modes of methane in the dissociation process. For low vibrational temperatures, very high vibrational efficacies are found, and energy in bend vibrations appears to dominate the dissociation of methane. The relative impact of vibrational nonequilibrium is much higher on terrace sites than on surface steps. We then show how our simulations can help to interpret recent experimental results, and suggest new paths to a better understanding of plasma catalysis.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000674464100001 Publication Date 2021-09-30
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 OpenAccess
Notes Fonds Wetenschappelijk Onderzoek, 12ZI420N ; K M B was funded as a junior postdoctoral fellow of the FWO (Research Foundation—Flanders), Grant 12ZI420N. The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government. HLDA calculations were performed with a script provided by G Piccini. Approved Most recent IF: 2.588
Call Number PLASMANT @ plasmant @c:irua:179830 Serial 6808
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Author Engelmann, Y.; van ’t Veer, K.; Gorbanev, Y.; Neyts, E.C.; Schneider, W.F.; Bogaerts, A.
Title Plasma Catalysis for Ammonia Synthesis: A Microkinetic Modeling Study on the Contributions of Eley–Rideal Reactions Type A1 Journal Article;Plasma catalysis
Year 2021 Publication Acs Sustainable Chemistry & Engineering Abbreviated Journal Acs Sustain Chem Eng
Volume 9 Issue 39 Pages 13151-13163
Keywords A1 Journal Article;Plasma catalysis; Eley−Rideal reactions; Volcano plots; Vibrational excitation; Radical reactions; Dielectric barrier discharge; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract Plasma catalysis is an emerging new technology for the electrification and downscaling of NH3 synthesis. Increasing attention is being paid to the optimization of plasma catalysis with respect to the plasma conditions, the catalyst material, and their mutual interaction. In this work we use microkinetic models to study how the total conversion process is impacted by the combination of different plasma conditions and transition metal catalysts. We study how plasma-generated radicals and vibrationally excited N2 (present in a dielectric barrier discharge plasma) interact with the catalyst and impact the NH3 turnover frequencies (TOFs). Both filamentary and uniform plasmas are studied, based on plasma chemistry models that provided plasma phase speciation and vibrational distribution functions. The Langmuir−Hinshelwood reaction rate coefficients (i.e., adsorption reactions and subsequent reactions among adsorbates) are determined using conventional scaling relations. An additional set of Eley−Rideal reactions (i.e., direct reactions of plasma radicals with adsorbates) was added and a sensitivity analysis on the assumed reaction rate coefficients was performed. We first show the impact of different vibrational distribution functions on the catalytic dissociation of N2 and subsequent production of NH3, and we gradually include more radical reactions, to illustrate the contribution of these species and their corresponding reaction pathways. Analysis over a large range of catalysts indicates that different transition metals (metals such as Rh, Ni, Pt, and Pd) optimize the NH3TOFs depending on the population of the vibrational levels of N2. At higher concentrations of plasma-generated radicals, the NH3 TOFs become less dependent on the catalyst material, due to radical adsorptions on the more noble catalysts and Eley−Rideal reactions on the less noble catalysts.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000705367800004 Publication Date 2021-10-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2168-0485 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.951 Times cited Open Access OpenAccess
Notes Basic Energy Sciences, DE-SC0021107 ; Vlaamse regering, HBC.2019.0108 ; H2020 European Research Council, 810182 ; Methusalem project – University of Antwerp; Excellence of science FWO-FNRS, GoF9618n ; TOP-BOF – University of Antwerp; DOCPRO3 – University of Antwerp; We acknowledge the financial support from the DOC-PRO3, the TOP-BOF, and the Methusalem project of the University of Antwerp, as well as from the European Research Council (ERC) (grant agreement No, 810182−SCOPE ERC Synergy project), under the European Union’s Horizon 2020 research and innovation programme, the Flemish Government through the Moonshot cSBO project P2C (HBC.2019.0108), and the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023). Calculations were carried out 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), 13162 Approved Most recent IF: 5.951
Call Number PLASMANT @ plasmant @c:irua:182482 Serial 6811
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Author Bogaerts, A.; Neyts, E.C.; Guaitella, O.; Murphy, A.B.
Title Foundations of plasma catalysis for environmental applications Type A1 Journal article
Year 2022 Publication Plasma Sources Science & Technology Abbreviated Journal Plasma Sources Sci T
Volume Issue Pages
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma catalysis is gaining increasing interest for various applications, but the underlying mechanisms are still far from understood. Hence, more fundamental research is needed to understand these mechanisms. This can be obtained by both modelling and experiments. This foundations paper describes the fundamental insights in plasma catalysis, as well as efforts to gain more insights by modelling and experiments. Furthermore, it discusses the state-of-the-art of the major plasma catalysis applications, as well as successes and challenges of technology transfer of these applications.
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Publisher Place of Publication Editor
Language Wos 000804396200001 Publication Date 2022-03-21
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 3.8 Times cited Open Access OpenAccess
Notes H2020 Marie Skłodowska-Curie Actions, 823745 ; H2020 European Research Council, 810182 ; We acknowldege financial support from 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). Approved Most recent IF: 3.8
Call Number PLASMANT @ plasmant @c:irua:188539 Serial 7070
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Author Nematollahi, P.; Barbiellini, B.; Bansil, A.; Lamoen, D.; Qingying, J.; Mukerjee, S.; Neyts, E.C.
Title Identification of a Robust and Durable FeN4CxCatalyst for ORR in PEM Fuel Cells and the Role of the Fifth Ligand Type A1 Journal article
Year 2022 Publication ACS catalysis Abbreviated Journal Acs Catal
Volume Issue Pages 7541-7549
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Although recent studies have advanced the understanding of pyrolyzed

Fe−N−C materials as oxygen reduction reaction (ORR) catalysts, the atomic and

electronic structures of the active sites and their detailed reaction mechanisms still remain unknown. Here, based on first-principles density functional theory (DFT) computations, we discuss the electronic structures of three FeN4 catalytic centers with different local topologies of the surrounding C atoms with a focus on unraveling the mechanism of their ORR activity in acidic electrolytes. Our study brings back a forgotten, synthesized pyridinic Fe−N coordinate to the community’s attention, demonstrating that this catalyst can exhibit excellent activity for promoting direct four-electron ORR through the addition of a fifth ligand such as −NH2, −OH, and −SO4. We also identify sites with good stability properties through the combined use of our DFT calculations and Mössbauer spectroscopy data.
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Language Wos 000823193100001 Publication Date 2022-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2155-5435 ISBN Additional Links UA library record; WoS full record; WoS full record; WoS citing articles
Impact Factor 12.9 Times cited Open Access OpenAccess
Notes Basic Energy Sciences, DE-FG02-07ER46352 ; Fonds Wetenschappelijk Onderzoek, 1261721N ; Opetus- ja Kulttuuriministeri?; Department of Energy, DE-EE0008416 ; Approved Most recent IF: 12.9
Call Number EMAT @ emat @c:irua:189000 Serial 7073
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Author Faraji, F.; Neyts, E.C.; Milošević, M.V.; Peeters, F.M.
Title Comment on “Misinterpretation of the Shuttleworth equation” Type A1 Journal Article
Year 2024 Publication Scripta Materialia Abbreviated Journal Scripta Materialia
Volume 250 Issue Pages 116186
Keywords A1 Journal Article; CMT
Abstract
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Language Wos Publication Date 2024-05-24
Series Editor Series Title Abbreviated Series Title
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ISSN 1359-6462 ISBN Additional Links
Impact Factor 6 Times cited Open Access
Notes Research Foundation Flanders; Approved Most recent IF: 6; 2024 IF: 3.747
Call Number UA @ lucian @ CMT Serial 9116
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Author Faraji, F.; Neyts, E.C.; Milošević, M.V.; Peeters, F.M.
Title Capillary Condensation of Water in Graphene Nanocapillaries Type A1 Journal Article
Year 2024 Publication Nano Letters Abbreviated Journal Nano Lett.
Volume 24 Issue 18 Pages 5625-5630
Keywords A1 Journal Article; CMT
Abstract Recent experiments have revealed that the macroscopic Kelvin equation remains surprisingly accurate even for nanoscale capillaries. This phenomenon was so far explained by the oscillatory behavior of the solid−liquid interfacial free energy. We here demonstrate thermodynamic and capillarity inconsistencies with this explanation. After revising the Kelvin equation, we ascribe its validity at nanoscale confinement to the effect of disjoining pressure.

To substantiate our hypothesis, we employed molecular dynamics simulations to evaluate interfacial heat transfer and wetting properties. Our assessments unveil a breakdown in a previously established proportionality between the work of adhesion and the Kapitza conductance at capillary heights below 1.3 nm, where the dominance of the work of adhesion shifts primarily from energy to entropy. Alternatively, the peak density of the initial water layer can effectively probe the work of adhesion. Unlike under bulk conditions, high confinement renders the work of adhesion entropically unfavorable.
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Publisher Place of Publication Editor
Language Wos Publication Date 2024-05-08
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Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links
Impact Factor 10.8 Times cited Open Access
Notes This work was supported by Research Foundation-Flanders (FWO, project No. G099219N). The computational resources used in this work were provided by the HPC core facility CalcUA of the University of Antwerp, and the Flemish Supercomputer Center (VSC), funded by FWO and the Flemish Government. Approved Most recent IF: 10.8; 2024 IF: 12.712
Call Number UA @ lucian @ Serial 9123
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