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Author | Engelmann; Bogaerts, A.; Neyts, E.C. | ||||
Title | Thermodynamics at the nanoscale: phase diagrams of nickel-carbon nanoclusters and equilibrium constants for phase transitions | Type | A1 Journal article | ||
Year | 2014 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 6 | Issue | 20 | Pages | 11981-11987 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Using reactive molecular dynamics simulations, the melting behavior of nickel-carbon nanoclusters is examined. The phase diagrams of icosahedral and Wulff polyhedron clusters are determined using both the Lindemann index and the potential energy. Formulae are derived for calculating the equilibrium constants and the solid and liquid fractions during a phase transition, allowing more rational determination of the melting temperature with respect to the arbitrary Lindemann value. These results give more insight into the properties of nickel-carbon nanoclusters in general and can specifically be very useful for a better understanding of the synthesis of carbon nanotubes using the catalytic chemical vapor deposition method. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000343000800049 | Publication Date | 2014-07-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364;2040-3372; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
7.367 | Times cited | 20 | Open Access | |
Notes | Approved | Most recent IF: 7.367; 2014 IF: 7.394 | |||
Call Number | UA @ lucian @ c:irua:121106 | Serial | 3637 | ||
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Author | Khalilov, U.; Bogaerts, A.; Xu, B.; Kato, T.; Kaneko, T.; Neyts, E.C. | ||||
Title | How the alignment of adsorbed ortho H pairs determines the onset of selective carbon nanotube etching | Type | A1 Journal article | ||
Year | 2017 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 9 | Issue | 9 | Pages | 1653-1661 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Unlocking the enormous technological potential of carbon nanotubes strongly depends on our ability to specifically produce metallic or semiconducting tubes. While selective etching of both has already been demonstrated, the underlying reasons, however, remain elusive as yet. We here present computational and experimental evidence on the operative mechanisms at the atomic scale. We demonstrate that during the adsorption of H atoms and their coalescence, the adsorbed ortho hydrogen pairs on single-walled carbon nanotubes induce higher shear stresses than axial stresses, leading to the elongation of HC–CH bonds as a function of their alignment with the tube chirality vector, which we denote as the γ-angle. As a result, the C–C cleavage occurs more rapidly in nanotubes containing ortho H-pairs with a small γ-angle. This phenomenon can explain the selective etching of small-diameter semiconductor nanotubes with a similar curvature. Both theoretical and experimental results strongly indicate the important role of the γ-angle in the selective etching mechanisms of carbon nanotubes, in addition to the nanotube curvature and metallicity effects and lead us to clearly understand the onset of selective synthesis/removal of CNT-based materials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000395422800036 | Publication Date | 2016-12-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
7.367 | Times cited | 6 | Open Access | OpenAccess |
Notes | U. K. gratefully acknowledges financial support from the Fund of Scientific Research Flanders (FWO), Belgium (Grant No. 12M1315N). This work was also supported in part by Grant-in- Aid for Young Scientists A (Grant No. 25706028), Grant-in-Aid for Scientific Research on Innovative Areas (Grant No. 26107502) from JSPS KAKENHI. This work was carried out in part 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. The authors also thank Prof. A. C. T. van Duin for sharing the ReaxFF code and J. Razzokov for his assistance to perform the DFT calculations. | Approved | Most recent IF: 7.367 | ||
Call Number | PLASMANT @ plasmant @ c:irua:140091 | Serial | 4417 | ||
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Author | Khalilov, U.; Uljayev, U.; Mehmonov, K.; Nematollahi, P.; Yusupov, M.; Neyts, E.C.; Neyts, E.C. | ||||
Title | Can endohedral transition metals enhance hydrogen storage in carbon nanotubes? | Type | A1 Journal article | ||
Year | 2024 | Publication | International journal of hydrogen energy | Abbreviated Journal | |
Volume | 55 | Issue | Pages | 640-610 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Modelling and Simulation in Chemistry (MOSAIC); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The safe and efficient use of hydrogen energy, which is in high demand worldwide today, requires efficient hydrogen storage. Despite significant advances in hydrogen storage using carbon-based nanomaterials, including carbon nanotubes (CNTs), efforts to substantially increase the storage capacity remain less effective. In this work, we demonstrate the effect of endohedral transition metal atoms on the hydrogen storage capacity of CNTs using reactive molecular dynamics simulations. We find that an increase in the volume fraction of endohedral nickel atoms leads to an increase in the concentration of physisorbed hydrogen molecules around single-walled CNTs (SWNTs) by approximately 1.6 times compared to pure SWNTs. The obtained results provide insight into the underlying mechanisms of how endohedral transition metal atoms enhance the hydrogen storage ability of SWNTs under nearly ambient conditions. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001142427400001 | Publication Date | 2023-11-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0360-3199 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
7.2 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 7.2; 2024 IF: 3.582 | |||
Call Number | UA @ admin @ c:irua:202315 | Serial | 9006 | ||
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Author | Heyne, M.H.; Marinov, D.; Braithwaite, N.; Goodyear, A.; de Marneffe, J.-F.; Cooke, M.; Radu, I.; Neyts, E.C.; De Gendt, S. | ||||
Title | A route towards the fabrication of 2D heterostructures using atomic layer etching combined with selective conversion | Type | A1 Journal article | ||
Year | 2019 | Publication | 2D materials | Abbreviated Journal | 2D Mater |
Volume | 6 | Issue | 3 | Pages | 035030 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Heterostructures of low-dimensional semiconducting materials, such as transition metal dichalcogenides (MX2), are promising building blocks for future electronic and optoelectronic devices. The patterning of one MX2 material on top of another one is challenging due to their structural similarity. This prevents an intrinsic etch stop when conventional anisotropic dry etching processes are used. An alternative approach consist in a two-step process, where a sacrificial silicon layer is pre-patterned with a low damage plasma process, stopping on the underlying MoS2 film. The pre-patterned layer is used as sacrificial template for the formation of the top WS2 film. This study describes the optimization of a cyclic Ar/Cl-2 atomic layer etch process applied to etch silicon on top of MoS2, with minimal damage, followed by a selective conversion of the patterned Si into WS2. The impact of the Si atomic layer etch towards the MoS2 is evaluated: in the ion energy range used for this study, MoS2 removal occurs in the over-etch step over 1-2 layers, leading to the appearance of MoOx but without significant lattice distortions to the remaining layers. The combination of Si atomic layer etch, on top of MoS2, and subsequent Si-to-WS2 selective conversion, allows to create a WS2/MoS2 heterostructure, with clear Raman signals and horizontal lattice alignment. These results demonstrate a scalable, transfer free method to achieve horizontally individually patterned heterostacks and open the route towards wafer-level processing of 2D materials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000468335500004 | Publication Date | 2019-04-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2053-1583 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
6.937 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 6.937 | |||
Call Number | UA @ admin @ c:irua:160229 | Serial | 5266 | ||
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Author | Faraji, F.; Neek-Amal, M.; Neyts, E.C.; Peeters, F.M. | ||||
Title | Indentation of graphene nano-bubbles | Type | A1 Journal article | ||
Year | 2022 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 14 | Issue | 15 | Pages | 5876-5883 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Molecular dynamics simulations are used to investigate the effect of an AFM tip when indenting graphene nano bubbles filled by a noble gas (i.e. He, Ne and Ar) up to the breaking point. The failure points resemble those of viral shells as described by the Foppl-von Karman (FvK) dimensionless number defined in the context of elasticity theory of thin shells. At room temperature, He gas inside the bubbles is found to be in the liquid state while Ne and Ar atoms are in the solid state although the pressure inside the nano bubble is below the melting pressure of the bulk. The trapped gases are under higher hydrostatic pressure at low temperatures than at room temperature. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000776763000001 | Publication Date | 2022-03-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364; 2040-3372 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
6.7 | Times cited | 2 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 6.7 | |||
Call Number | UA @ admin @ c:irua:187924 | Serial | 7171 | ||
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Author | Neyts, E.C.; Bogaerts, A. | ||||
Title | Formation of endohedral Ni@C60 and exohedral NiC60 metallofullerene complexes by simulated ion implantation | Type | A1 Journal article | ||
Year | 2009 | Publication | Carbon | Abbreviated Journal | Carbon |
Volume | 47 | Issue | 4 | Pages | 1028-1033 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The interaction of thermal and hyperthermal Ni ions with gas-phase C60 fullerene was investigated at two temperatures with classical molecular dynamics simulations using a recently developed interatomic many-body potential. The interaction between Ni and C60 is characterized in terms of the NiC60 binding sites, complex formation, and the collision and temperature induced deformation of the C60 cage structure. The simulations show how ion implantation theoretically allows the synthesis of both endohedral Ni@C60 and exohedral NiC60 metallofullerene complexes. | ||||
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Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000264252900012 | Publication Date | 2008-12-25 | |
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 | 15 | Open Access | |
Notes | Approved | Most recent IF: 6.337; 2009 IF: 4.504 | |||
Call Number | UA @ lucian @ c:irua:76434 | Serial | 1260 | ||
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Author | Neyts, E.C.; Bogaerts, A. | ||||
Title | Ion irradiation for improved graphene network formation in carbon nanotube growth | Type | A1 Journal article | ||
Year | 2014 | Publication | Carbon | Abbreviated Journal | Carbon |
Volume | 77 | Issue | Pages | 790-795 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Ion irradiation of carbon nanotubes very often leads to defect formation. However, we have recently shown that Ar ion irradiation in a limited energy window of 1025 eV may enhance the initial cap nucleation process, when the carbon network is in contact with the metal nanocatalyst. Here, we employ reactive molecular dynamics simulations to demonstrate that ion irradiation in a higher energy window of 1035 eV may also heal network defects after the nucleation stage through a non-metal-mediated mechanism, when the carbon network is no longer in contact with the metal nanocatalyst. The results demonstrate the possibility of beneficially utilizing ions in e.g. plasma-enhanced chemical vapour deposition of carbon nanotubes. | ||||
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Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000340689400083 | Publication Date | 2014-06-11 | |
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 | 7 | Open Access | |
Notes | Approved | Most recent IF: 6.337; 2014 IF: 6.196 | |||
Call Number | UA @ lucian @ c:irua:118062 | Serial | 1745 | ||
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Author | Shariat, M.; Hosseini, S.I.; Shokri, B.; Neyts, E.C. | ||||
Title | Plasma enhanced growth of single walled carbon nanotubes at low temperature : a reactive molecular dynamics simulation | Type | A1 Journal article | ||
Year | 2013 | Publication | Carbon | Abbreviated Journal | Carbon |
Volume | 65 | Issue | Pages | 269-276 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Low-temperature growth of carbon nanotubes (CNTs) has been claimed to provide a route towards chiral-selective growth, enabling a host of applications. In this contribution, we employ reactive molecular dynamics simulations to demonstrate how plasma-based deposition allows such low-temperature growth. We first show how ion bombardment during the growth affects the carbon dissolution and precipitation process. We then continue to demonstrate how a narrow ion energy window allows CNT growth at 500 K. Finally, we also show how CNTs in contrast cannot be grown in thermal CVD at this low temperature, but only at high temperature, in agreement with experimental data. (C) 2013 Elsevier Ltd. All rights reserved. | ||||
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Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000326773200031 | Publication Date | 2013-08-23 | |
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 | 21 | Open Access | |
Notes | Approved | Most recent IF: 6.337; 2013 IF: 6.160 | |||
Call Number | UA @ lucian @ c:irua:112697 | Serial | 2635 | ||
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Author | Khalilov, U.; Bogaerts, A.; Neyts, E.C. | ||||
Title | Atomic-scale mechanisms of plasma-assisted elimination of nascent base-grown carbon nanotubes | Type | A1 Journal article | ||
Year | 2017 | Publication | Carbon | Abbreviated Journal | Carbon |
Volume | 118 | Issue | 118 | Pages | 452-457 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Selective etching allows for obtaining carbon nanotubes with a specific chirality. While plasma-assisted etching has already been used to separate metallic tubes from their semiconducting counterparts, little is known about the nanoscale mechanisms of the etching process. We combine (reactive) molecular dynamics (MD) and force-bias Monte Carlo (tfMC) simulations to study H-etching of CNTs. In particular, during the hydrogenation and subsequent etching of both the carbon cap and the tube, they sequentially transform to different carbon nanostructures, including carbon nanosheet, nanowall, and polyyne chains, before they are completely removed from the surface of a substrate-bound Ni-nanocluster.We also found that onset of the etching process is different in the cases of the cap and the tube, although the overall etching scenario is similar in both cases. The entire hydrogenation/etching process for both cases is analysed in detail, comparing with available theoretical and experimental evidences. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000401120800053 | Publication Date | 2017-03-26 | |
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 | 2 | Open Access | OpenAccess |
Notes | U. K. gratefully acknowledges financial support from the Research Foundation – Flanders (FWO), Belgium (Grant No. 12M1315N). 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 Universiteit Antwerpen. The authors also thank Prof. A. C. T. van Duin for sharing the ReaxFF code. | Approved | Most recent IF: 6.337 | ||
Call Number | PLASMANT @ plasmant @ c:irua:141915 | Serial | 4531 | ||
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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 | 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 | 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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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 | 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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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 | Kovács, A.; Yusupov, M.; Cornet, I.; Billen, P.; Neyts, E.C. | ||||
Title | Effect of natural deep eutectic solvents of non-eutectic compositions on enzyme stability | Type | A1 Journal article | ||
Year | 2022 | Publication | Journal Of Molecular Liquids | Abbreviated Journal | J Mol Liq |
Volume | 366 | Issue | Pages | 120180-17 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Biochemical Wastewater Valorization & Engineering (BioWaVE); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) | ||||
Abstract | Natural deep eutectic solvents (NADES) represent a green alternative to common organic solvents in the biochemical industry due to their benign behavior and tailorable properties, in particular as media for enzymatic reactions. However, to fully exploit their potential in enzymatic reactions, there is a need for a more fundamental understanding of how these neoteric solvents influence the course of these reac-tions. Thus, the aim of this study is to investigate the influence of NADES with various molar composi-tions on the stability and structure of enzymes, applying molecular dynamics simulations. This can help to better understand the effect of individual compounds of NADES, in addition to eutectic mixtures. More specifically, we simulate the behavior of Candida antarctica lipase B (CALB) enzyme in NADES com-posed of choline chloride with either urea, ethylene glycol or glycerol. Hereto, we monitor the NADES microstructure, the general stability of the enzyme and changes in the structure of its active sites and sur-face residues. Our simulations show that none of the studied NADES systems significantly disrupt the microstructure of the solvent or the stability of the CALB enzyme within the time scales of the simula-tions. The enzyme preserves its initial structure, size and intra-chain hydrogen bonds in all investigated compositions and, for the first time reported, also in NADES with increased hydrogen bond donating com-pound ratios. As the main novelty, our results indicate that, in addition to the composition, the molar ratio can be an additional variable to fine-tune the physicochemical properties of NADES without altering the enzyme characteristics. These findings could facilitate the development and application of task -tailored NADES media for biocatalytic processes. (c) 2022 Elsevier B.V. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000865431800010 | Publication Date | 2022-08-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0167-7322 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor ![]() |
6 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 6 | |||
Call Number | UA @ admin @ c:irua:191538 | Serial | 7265 | ||
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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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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2024-05-24 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 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 | 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 | 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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Corporate Author | Thesis | ||||
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 | Nematollahi, P.; Neyts, E.C. | ||||
Title | Direct oxidation of methane to methanol on Co embedded N-doped graphene: Comparing the role of N₂O and O₂ as oxidants | Type | A1 Journal article | ||
Year | 2020 | Publication | Applied Catalysis A-General | Abbreviated Journal | Appl Catal A-Gen |
Volume | 602 | Issue | Pages | 117716-10 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this work, the effects of N-doping into the Co-doped single vacancy (Co-SV-G) and di-vacancy graphene flake (Co-dV-G) are investigated and compared toward direct oxidation of methane to methanol (DOMM) employing two different oxidants (N2O and O-2) using density functional theory (DFT) calculation. We found that DOMM on CoN3-G utilizing the N2O molecule as oxygen-donor proceeds via a two-step reaction with low activation energies. In addition, we found that although CoN3-G might be a good catalyst for methane conversion, it can also catalyze the oxidation of methanol to CO2 and H2O due to the required low activation barriers. Moreover, the adsorption behaviors of CHx (x = 0-4) species and dehydrogenation of CHx (x = 1-4) species on CoN3-G are investigated. We concluded that CoN3-G can be used as an efficient catalyst for DOMM and N-2O reduction at ambient conditions which may serve as a guide for fabricating effective C/N catalysts in energy-related devices. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000554006800046 | Publication Date | 2020-06-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0926-860x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
5.5 | Times cited | Open Access | ||
Notes | ; This work was performed with the financial support from the Doctoral Fund of the Antwerp University (NO. BOFLP33099). All the simulations are performed on resources provided by the high-performance computing center of Antwerp University. ; | Approved | Most recent IF: 5.5; 2020 IF: 4.339 | ||
Call Number | UA @ admin @ c:irua:171219 | Serial | 6485 | ||
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Author | Heyne, M.H.; Chiappe, D.; Meersschaut, J.; Nuytten, T.; Conard, T.; Bender, H.; Huyghebaert, C.; Radu, I.P.; Caymax, M.; de Marneffe, J.F.; Neyts, E.C.; De Gendt, S.; | ||||
Title | Multilayer MoS2 growth by metal and metal oxide sulfurization | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of materials chemistry C : materials for optical and electronic devices | Abbreviated Journal | J Mater Chem C |
Volume | 4 | Issue | 4 | Pages | 1295-1304 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We investigated the deposition of MoS2 multilayers on large area substrates. The pre-deposition of metal or metal oxide with subsequent sulfurization is a promising technique to achieve layered films. We distinguish a different reaction behavior in metal oxide and metallic films and investigate the effect of the temperature, the H2S/H-2 gas mixture composition, and the role of the underlying substrate on the material quality. The results of the experiments suggest a MoS2 growth mechanism consisting of two subsequent process steps. At first, the reaction of the sulfur precursor with the metal or metal oxide occurs, requiring higher temperatures in the case of metallic film compared to metal oxide. At this stage, the basal planes assemble towards the diffusion direction of the reaction educts and products. After the sulfurization reaction, the material recrystallizes and the basal planes rearrange parallel to the substrate to minimize the surface energy. Therefore, substrates with low roughness show basal plane assembly parallel to the substrate. These results indicate that the substrate character has a significant impact on the assembly of low dimensional MoS2 films. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000370723300020 | Publication Date | 2016-01-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2050-7526; 2050-7534 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
5.256 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 5.256 | |||
Call Number | UA @ lucian @ c:irua:132327 | Serial | 4211 | ||
Permanent link to this record | |||||
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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Corporate Author | Thesis | ||||
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 | Neyts, E.C.; Thijsse, B.J.; Mees, M.J.; Bal, K.M.; Pourtois, G. | ||||
Title | Establishing uniform acceptance in force biased Monte Carlo simulations | Type | A1 Journal article | ||
Year | 2012 | Publication | Journal of chemical theory and computation | Abbreviated Journal | J Chem Theory Comput |
Volume | 8 | Issue | 6 | Pages | 1865-1869 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Uniform acceptance force biased Monte Carlo (UFMC) simulations have previously been shown to be a powerful tool to simulate atomic scale processes, enabling one to follow the dynamical path during the simulation. In this contribution, we present a simple proof to demonstrate that this uniform acceptance still complies with the condition of detailed balance, on the condition that the characteristic parameter lambda = 1/2 and that the maximum allowed step size is chosen to be sufficiently small. Furthermore, the relation to Metropolis Monte Carlo (MMC) is also established, and it is shown that UFMC reduces to MMC by choosing the characteristic parameter lambda = 0 [Rao, M. et al. Mol. Phys. 1979, 37, 1773]. Finally, a simple example compares the UFMC and MMC methods. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000305092400002 | Publication Date | 2012-05-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1549-9618;1549-9626; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
5.245 | Times cited | 20 | Open Access | |
Notes | Approved | Most recent IF: 5.245; 2012 IF: 5.389 | |||
Call Number | UA @ lucian @ c:irua:99090 | Serial | 1082 | ||
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Author | Bal, K.M.; Neyts, E.C. | ||||
Title | Merging Metadynamics into Hyperdynamics: Accelerated Molecular Simulations Reaching Time Scales from Microseconds to Seconds | Type | A1 Journal article | ||
Year | 2015 | Publication | Journal of chemical theory and computation | Abbreviated Journal | J Chem Theory Comput |
Volume | 11 | Issue | 11 | Pages | 4545-4554 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The hyperdynamics method is a powerful tool to simulate slow processes at the atomic level. However, the construction of an optimal hyperdynamics potential is a task that is far from trivial. Here, we propose a generally applicable implementation of the hyperdynamics algorithm, borrowing two concepts from metadynamics. First, the use of a collective variable (CV) to represent the accelerated dynamics gives the method a very large flexibility and simplicity. Second, a metadynamics procedure can be used to construct a suitable history-dependent bias potential on-the-fly, effectively turning the algorithm into a self-learning accelerated molecular dynamics method. This collective variable-driven hyperdynamics (CVHD) method has a modular design: both the local system properties on which the bias is based, as well as the characteristics of the biasing method itself, can be chosen to match the needs of the considered system. As a result, system-specific details are abstracted from the biasing algorithm itself, making it extremely versatile and transparent. The method is tested on three model systems: diffusion on the Cu(001) surface and nickel-catalyzed methane decomposition, as examples of reactive processes with a bond-length-based CV, and the folding of a long polymer-like chain, using a set of dihedral angles as a CV. Boost factors up to 109, corresponding to a time scale of seconds, could be obtained while still accurately reproducing correct dynamics. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000362921700004 | Publication Date | 2015-09-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1549-9618 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
5.245 | Times cited | 41 | Open Access | |
Notes | K.M.B. is funded as Ph.D. fellow (aspirant) of the FWOFlanders (Fund for Scientific Research-Flanders), Grant No. 11 V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), funded by the Hercules Foundation and the Flemish Government−Department EWI. | Approved | Most recent IF: 5.245; 2015 IF: 5.498 | ||
Call Number | c:irua:128183 | Serial | 3991 | ||
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Author | Yusupov, M.; Van der Paal, J.; Neyts, E.C.; Bogaerts, A. | ||||
Title | Synergistic effect of electric field and lipid oxidation on the permeability of cell membranes | Type | A1 Journal article | ||
Year | 2017 | Publication | Biochimica et biophysica acta : G : general subjects | Abbreviated Journal | Bba-Gen Subjects |
Volume | 1861 | Issue | 1861 | Pages | 839-847 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Background: Strong electric fields are knownto affect cell membrane permeability,which can be applied for therapeutic purposes, e.g., in cancer therapy. A synergistic enhancement of this effect may be accomplished by the presence of reactive oxygen species (ROS), as generated in cold atmospheric plasmas. Little is known about the synergy between lipid oxidation by ROS and the electric field, nor on howthis affects the cell membrane permeability. Method: We here conduct molecular dynamics simulations to elucidate the dynamics of the permeation process under the influence of combined lipid oxidation and electroporation. A phospholipid bilayer (PLB), consisting of di-oleoyl-phosphatidylcholine molecules covered with water layers, is used as a model system for the plasma membrane. Results and conclusions:Weshow howoxidation of the lipids in the PLB leads to an increase of the permeability of the bilayer to ROS, although the permeation free energy barriers still remain relatively high. More importantly, oxidation of the lipids results in a drop of the electric field threshold needed for pore formation (i.e., electroporation) in the PLB. The created pores in the membrane facilitate the penetration of reactive plasma species deep into the cell interior, eventually causing oxidative damage. General significance: This study is of particular interest for plasma medicine, as plasma generates both ROS and electric fields, but it is also of more general interest for applications where strong electric fields and ROS both come into play. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000397366200012 | Publication Date | 2017-01-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-4165 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.702 | Times cited | Open Access | OpenAccess | |
Notes | This work is financially supported by the Fund for Scientific Research Flanders (FWO; grant numbers: 1200216N and 11U5416N). The work was carried out 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 Flem | Approved | Most recent IF: 4.702 | ||
Call Number | PLASMANT @ plasmant @ c:irua:140095 | Serial | 4413 | ||
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Author | Brault, P.; Neyts, E.C. | ||||
Title | Molecular dynamics simulations of supported metal nanocatalyst formation by plasma sputtering | Type | A1 Journal article | ||
Year | 2015 | Publication | Catalysis today | Abbreviated Journal | Catal Today |
Volume | 256 | Issue | 256 | Pages | 3-12 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Magnetron sputtering is a widely used physical vapor deposition technique for deposition and formation of nanocatalyst thin films and clusters. Nevertheless, so far only few studies investigated this formation process at the fundamental level. We here review atomic scale molecular dynamics simulations aimed at elucidating the nanocatalyst growth process through magnetron sputtering. We first introduce the basic magnetron sputtering background and machinery of molecular dynamics simulations, and then describe the studies conducted in this field so far. We also present a perspective view on how the field may be developed further. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000360085300002 | Publication Date | 2015-02-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0920-5861; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.636 | Times cited | 18 | Open Access | |
Notes | Approved | Most recent IF: 4.636; 2015 IF: 3.893 | |||
Call Number | c:irua:127408 | Serial | 2174 | ||
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Author | Neyts, E.C.; Ostrikov, K.(K.) | ||||
Title | Nanoscale thermodynamic aspects of plasma catalysis | Type | A1 Journal article | ||
Year | 2015 | Publication | Catalysis today | Abbreviated Journal | Catal Today |
Volume | 256 | Issue | 256 | Pages | 23-28 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma catalysis continues to gain increasing scientific interest, both in established fields like toxic waste abatement and emerging fields like greenhouse gas conversion into value-added chemicals. Attention is typically focused on the obtained conversion process selectivity, rates and energy efficiency. Much less attention is usually paid to the underlying mechanistic aspects of the processes that occur. In this contribution, we critically examine a number of fundamentally important nanoscale thermodynamic aspects of plasma catalysis, which are very relevant to these processes but so far have been overlooked or insufficiently covered in the plasma catalysis literature. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000360085300004 | Publication Date | 2015-03-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0920-5861; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.636 | Times cited | 14 | Open Access | |
Notes | Approved | Most recent IF: 4.636; 2015 IF: 3.893 | |||
Call Number | c:irua:127409 | Serial | 2274 | ||
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Author | Nozaki, T.; Neyts, E.C.; Sankaran, M.; Ostrikov, K.(K.); Liu, C.-J. | ||||
Title | Plasmas for enhanced catalytic processes (ISPCEM 2014) | Type | Editorial | ||
Year | 2015 | Publication | Catalysis today | Abbreviated Journal | Catal Today |
Volume | 256 | Issue | 256 | Pages | 1-2 |
Keywords | Editorial; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | |||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000360085300001 | Publication Date | 2015-08-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0920-5861; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.636 | Times cited | 2 | Open Access | |
Notes | Approved | Most recent IF: 4.636; 2015 IF: 3.893 | |||
Call Number | c:irua:127407 | Serial | 2641 | ||
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Author | Somers, W.; Bogaerts, A.; van Duin, A.C.T.; Huygh, S.; Bal, K.M.; Neyts, E.C. | ||||
Title | Temperature influence on the reactivity of plasma species on a nickel catalyst surface : an atomic scale study | Type | A1 Journal article | ||
Year | 2013 | Publication | Catalysis today | Abbreviated Journal | Catal Today |
Volume | 211 | Issue | Pages | 131-136 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In recent years, the potential use of hydrogen as a clean energy source has gained considerable attention. Especially H2 formation by Ni-catalyzed reforming of methane at elevated temperatures is an attractive process. However, a more fundamental knowledge at the atomic level is needed for a full comprehension of the reactions at the catalyst surface. In this contribution, we therefore investigate the H2 formation after CHx impacts on a Ni(1 1 1) surface in the temperature range 4001600 K, by means of reactive molecular dynamics (MD) simulations using the ReaxFF potential. While some H2 formation is already observed at the lower temperatures, substantial H2 formation is only obtained at elevated temperatures of 1400 K and above. At 1600 K, the H2 molecules are even the most frequently formed species. In direct correlation with the increasing dehydrogenation at elevated temperatures, an increased surface-to-subsurface C-diffusivity is observed as well. This study highlights the major importance of the temperature on the H2 formation. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000320697800020 | Publication Date | 2013-03-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0920-5861; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.636 | Times cited | 27 | Open Access | |
Notes | Approved | Most recent IF: 4.636; 2013 IF: 3.309 | |||
Call Number | UA @ lucian @ c:irua:108675 | Serial | 3500 | ||
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Author | Huygh, S.; Neyts, E.C. | ||||
Title | Adsorption of C and CHx radicals on anatase (001) and the influence of oxygen vacancies | Type | A1 Journal article | ||
Year | 2015 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 119 | Issue | 119 | Pages | 4908-4921 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The adsorption of C and CHx radicals on anatase (001) was studied using DFT within the generalized gradient approximation using the Perde-Burke-Ernzerhof (PBE) functional. We have studied the influence of oxygen vacancies in and at the surface on the adsorption properties of the radicals. For the oxygen vacancies in anatase (001), the most stable vacancy is located at the surface. For this vacancy, the maximal adsorption strength of C and CH decreases compared to the adsorption on the stoichiometric surface, but it increases for CH2 and CH3. If an oxygen vacancy is present in the first subsurface layer, the maximal adsorption strength increases for C, CH, CH2, and CH3. When the vacancy is present in the next subsurface layer, we find that only the CH3 adsorption is enhanced, while the maximal adsorption energies for the other radical species decrease. Not only does the precise location of the oxygen vacancy determine the maximal adsorption interaction, it also influences the adsorption strengths of the radicals at different surface configurations. This determines the probability of finding a certain adsorption configuration at the surface, which in turn influences the possible surface reactions. We find that C preferentially adsorbs far away from the oxygen vacancy, while CH2 and CH3 adsorb preferentially at the oxygen vacancy site. A fraction of CH partially adsorbs at the oxygen vacancy, and another fraction adsorbs further away from the vacancy. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000350840700052 | Publication Date | 2015-02-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.536 | Times cited | 13 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2015 IF: 4.772 | |||
Call Number | c:irua:124909 | Serial | 63 | ||
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Author | Khalilov, U.; Neyts, E.C.; Pourtois, G.; van Duin, A.C.T. | ||||
Title | Can we control the thickness of ultrathin silica layers by hyperthermal silicon oxidation at room temperature? | Type | A1 Journal article | ||
Year | 2011 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 115 | Issue | 50 | Pages | 24839-24848 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Using reactive molecular dynamics simulations by means of the ReaxFF potential, we studied the growth mechanism of ultrathin silica (SiO2) layers during hyperthermal oxidation at room temperature. Oxidation of Si(100){2 × 1} surfaces by both atomic and molecular oxygen was investigated in the energy range 15 eV. The oxidation mechanism, which differs from thermal oxidation, is discussed. In the case of oxidation by molecular O2, silica is quickly formed and the thickness of the formed layers remains limited compared to oxidation by atomic oxygen. The Si/SiO2 interfaces are analyzed in terms of partial charges and angle distributions. The obtained structures of the ultrathin SiO2 films are amorphous, including some intrinsic defects. This study is important for the fabrication of silica-based devices in the micro- and nanoelectronics industry, and more specifically for the fabrication of metal oxide semiconductor devices. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000297947700050 | Publication Date | 2011-11-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.536 | Times cited | 36 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2011 IF: 4.805 | |||
Call Number | UA @ lucian @ c:irua:94303 | Serial | 273 | ||
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Author | Tinck, S.; Neyts, E.C.; Bogaerts, A. | ||||
Title | Fluorinesilicon surface reactions during cryogenic and near room temperature etching | Type | A1 Journal article | ||
Year | 2014 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 118 | Issue | 51 | Pages | 30315-30324 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Cyrogenic etching of silicon is envisaged to enable better control over plasma processing in the microelectronics industry, albeit little is known about the fundamental differences compared to the room temperature process. We here present molecular dynamics simulations carried out to obtain sticking probabilities, thermal desorption rates, surface diffusion speeds, and sputter yields of F, F2, Si, SiF, SiF2, SiF3, SiF4, and the corresponding ions on Si(100) and on SiF13 surfaces, both at cryogenic and near room temperature. The different surface behavior during conventional etching and cryoetching is discussed. F2 is found to be relatively reactive compared to other species like SiF03. Thermal desorption occurs at a significantly lower rate under cryogenic conditions, which results in an accumulation of physisorbed species. Moreover, ion incorporation is often observed for ions with energies of 30400 eV, which results in a relatively low net sputter yield. The obtained results suggest that the actual etching of Si, under both cryogenic and near room temperature conditions, is based on the complete conversion of the Si surface to physisorbed SiF4, followed by subsequent sputtering of these molecules, instead of direct sputtering of the SiF03 surface. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000347360200101 | Publication Date | 2014-11-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor ![]() |
4.536 | Times cited | 11 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2014 IF: 4.772 | |||
Call Number | UA @ lucian @ c:irua:122957 | Serial | 1239 | ||
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