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Author | Khalilov, U.; Pourtois, G.; van Duin, A.C.T.; Neyts, E.C. | ||||
Title | Self-limiting oxidation in small-diameter Si nanowires | Type | A1 Journal article | ||
Year | 2012 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 24 | Issue | 11 | Pages | 2141-2147 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Recently, core shell silicon nanowires (Si-NWs) have been envisaged to be used for field-effect transistors and photovoltaic applications. In spite of the constant downsizing of such devices, the formation of ultrasmall diameter core shell Si-NWs currently remains entirely unexplored. We report here on the modeling of the formation of such core shell Si-NWs using a dry thermal oxidation of 2 nm diameter (100) Si nanowires at 300 and 1273 K, by means of reactive molecular dynamics simulations using the ReaxFF potential. Two different oxidation mechanisms are discussed, namely a self-limiting process that occurs at low temperature (300 K), resulting in a Si core I ultrathin SiO2 silica shell nanowire, and a complete oxidation process that takes place at a higher temperature (1273 K), resulting in the formation of an ultrathin SiO2 silica nanowire. The oxidation kinetics of both cases and the resulting structures are analyzed in detail. Our results demonstrate that precise control over the Si-core radius of such NWs and the SiOx (x <= 2.0) oxide shell is possible by controlling the growth temperature used during the oxidation process. | ||||
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Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000305092600021 | Publication Date | 2012-05-18 | |
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ISSN | 0897-4756;1520-5002; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 45 | Open Access | |
Notes | Approved | Most recent IF: 9.466; 2012 IF: 8.238 | |||
Call Number | UA @ lucian @ c:irua:99079 | Serial | 2976 | ||
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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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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 | Jafarzadeh, A.; Bal, K.M.; Bogaerts, A.; Neyts, E.C. | ||||
Title | CO2 activation on TiO2-supported Cu5 and Ni5 nanoclusters : effect of plasma-induced surface charging | 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 | 11 | Pages | 6516-6525 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Surface charging is an often overlooked factor in many plasma-surface interactions and in particular in plasma catalysis. In this study, we investigate the effect of excess electrons induced by a plasma on the adsorption properties of CO2 on titania-supported Cu-5 and Ni-5 clusters using spin-polarized and dispersion-corrected density functional theory calculations. The effect of excess electrons on the adsorption of Ni and Cu pentamers as well as on CO2 adsorption on a pristine anatase TiO2(101) slab is studied. Our results indicate that adding plasma-induced excess electrons to the system leads to further stabilization of the bent CO2 structure. Also, dissociation of CO2 on charged clusters is energetically more favorable than on neutral clusters. We hypothesize that surface charge is a plausible cause for the synergistic effects sometimes observed in plasma catalysis. | ||||
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Language | Wos | 000462260700024 | Publication Date | 2019-02-21 | |
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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 | 4 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 4.536 | |||
Call Number | UA @ admin @ c:irua:159422 | Serial | 5281 | ||
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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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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 | Neyts, E.C.; Ostrikov, K.K.; Sunkara, M.K.; Bogaerts, A. | ||||
Title | Plasma Catalysis: Synergistic Effects at the Nanoscale | Type | A1 Journal article | ||
Year | 2015 | Publication | Chemical reviews | Abbreviated Journal | Chem Rev |
Volume | 115 | Issue | 115 | Pages | 13408-13446 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Thermal-catalytic gas processing is integral to many current industrial processes. Ever-increasing demands on conversion and energy efficiencies are a strong driving force for the development of alternative approaches. Similarly, synthesis of several functional materials (such as nanowires and nanotubes) demands special processing conditions. Plasma catalysis provides such an alternative, where the catalytic process is complemented by the use of plasmas that activate the source gas. This combination is often observed to result in a synergy between plasma and catalyst. This Review introduces the current state-of-the-art in plasma catalysis, including numerous examples where plasma catalysis has demonstrated its benefits or shows future potential, including CO2 conversion, hydrocarbon reforming, synthesis of nanomaterials, ammonia production, and abatement of toxic waste gases. The underlying mechanisms governing these applications, as resulting from the interaction between the plasma and the catalyst, render the process highly complex, and little is known about the factors leading to the often-observed synergy. This Review critically examines the catalytic mechanisms relevant to each specific application. | ||||
Address | Department of Chemistry, Research Group PLASMANT, Universiteit Antwerpen , Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium | ||||
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Language | English | Wos | 000367563000006 | Publication Date | 2015-11-30 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2665 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 47.928 | Times cited | 204 | Open Access | |
Notes | ECN and AB gratefully acknowledge financial support from the Fund of Scientific Research Flanders (FWO), Belgium, Grant Number G.0217.14N. KO acknowledges partial support by the Australian Research Council and CSIRO’s OCE Science Leaders Program. MKS acknowledges partial support from US National Science Foundation through grants DMS 1125909 and EPSCoR 1355448 and also PhD students Babajide Ajayi, Apolo Nambo and Maria Carreon for their help. | Approved | Most recent IF: 47.928; 2015 IF: 46.568 | ||
Call Number | c:irua:130001 | Serial | 3993 | ||
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Author | 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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Language | Wos | 000401120800053 | Publication Date | 2017-03-26 | |
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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 | 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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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 | Kato, T.; Neyts, E.C.; Abiko, Y.; Akama, T.; Hatakeyama, R.; Kaneko, T. | ||||
Title | Kinetics of energy selective Cs encapsulation in single-walled carbon nanotubes for damage-free and position-selective doping | 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 | 11903-11908 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | A method has been developed for damage-free cesium (Cs) encapsulation within single-walled carbon nanotubes (SWNTs) with fine position selectivity. Precise energy tuning of Cs-ion irradiation revealed that there is a clear energy window (2060 eV) for the efficient encapsulation of Cs through the hexagonal network of SWNT sidewalls without causing significant damage. This minimum energy threshold of Cs-ion encapsulation (∼20 eV) matches well with the value obtained by ab initio simulation (∼22 eV). Furthermore, position-selective Cs encapsulation was carried out, resulting in the successful formation of pn-junction SWNT thin films with excellent environmental stability. | ||||
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Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000355495600072 | Publication Date | 2015-05-06 | |
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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 | 3 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2015 IF: 4.772 | |||
Call Number | c:irua:125928 | Serial | 1760 | ||
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Author | Yusupov, M.; Neyts, E.C.; Verlackt, C.C.; Khalilov, U.; van Duin, A.C.T.; Bogaerts, A. | ||||
Title | Inactivation of the endotoxic biomolecule lipid A by oxygen plasma species : a reactive molecular dynamics study | Type | A1 Journal article | ||
Year | 2015 | Publication | Plasma processes and polymers | Abbreviated Journal | Plasma Process Polym |
Volume | 12 | Issue | 12 | Pages | 162-171 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Reactive molecular dynamics simulations are performed to study the interaction of reactive oxygen species, such as OH, HO2 and H2O2, with the endotoxic biomolecule lipid A of the gram-negative bacterium Escherichia coli. It is found that the aforementioned plasma species can destroy the lipid A, which consequently results in reducing its toxic activity. All bond dissociation events are initiated by hydrogen-abstraction reactions. However, the mechanisms behind these dissociations are dependent on the impinging plasma species, i.e. a clear difference is observed in the mechanisms upon impact of HO2 radicals and H2O2 molecules on one hand and OH radicals on the other hand. Our simulation results are in good agreement with experimental observations. | ||||
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Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000350275400005 | Publication Date | 2014-09-17 | |
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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 | 18 | Open Access | |
Notes | Approved | Most recent IF: 2.846; 2015 IF: 2.453 | |||
Call Number | c:irua:123540 | Serial | 1589 | ||
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Author | Bogaerts, A.; Yusupov, M.; Van der Paal, J.; Verlackt, C.C.W.; Neyts, E.C. | ||||
Title | Reactive molecular dynamics simulations for a better insight in plasma medicine | Type | A1 Journal article | ||
Year | 2014 | Publication | Plasma processes and polymers | Abbreviated Journal | Plasma Process Polym |
Volume | 11 | Issue | 12 | Pages | 1156-1168 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this review paper, we present several examples of reactive molecular dynamics simulations, which contribute to a better understanding of the underlying mechanisms in plasma medicine on the atomic scale. This includes the interaction of important reactive oxygen plasma species with the outer cell wall of both gram-positive and gram-negative bacteria, and with lipids present in human skin. Moreover, as most biomolecules are surrounded by a liquid biofilm, the behavior of these plasma species in a liquid (water) layer is presented as well. Finally, a perspective for future atomic scale modeling studies is given, in the field of plasma medicine in general, and for cancer treatment in particular. | ||||
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Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000346034700007 | Publication Date | 2014-09-29 | |
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ISSN | 1612-8850; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.846 | Times cited | 22 | Open Access | |
Notes | Approved | Most recent IF: 2.846; 2014 IF: 2.453 | |||
Call Number | UA @ lucian @ c:irua:121269 | Serial | 2822 | ||
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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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Language | Wos | 000526396900030 | Publication Date | 2020-03-26 | |
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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 Governmentdepartment 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 | Khalilov, U.; Yusupov, M.; Bogaerts, A.; Neyts, E.C. | ||||
Title | Selective Plasma Oxidation of Ultrasmall Si Nanowires | Type | A1 Journal article | ||
Year | 2016 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 120 | Issue | 120 | Pages | 472-477 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Device performance of Si|SiOx core-shell based nanowires critically depends on the exact control over the oxide thickness. Low-temperature plasma oxidation is a highly promising alternative to thermal oxidation allowing for improved control over the oxidation process, in particular for ultrasmall Si nanowires. We here elucidate the room temperature plasma oxidation mechanisms of ultrasmall Si nanowires using hybrid molecular dynamics / force-bias Monte Carlo simulations. We demonstrate how the oxidation and concurrent water formation mechanisms are a function of the oxidizing plasma species and we demonstrate how the resulting core-shell oxide thickness can be controlled through these species. A new mechanism of water formation is discussed in detail. The results provide a detailed atomic level explanation of the oxidation process of highly curved Si surfaces. These results point out a route toward plasma-based formation of ultrathin core-shell Si|SiOx nanowires at room temperature. | ||||
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Language | Wos | 000368562200057 | Publication Date | 2015-12-21 | |
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ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 3 | Open Access | |
Notes | U.K. and M.Y. gratefully acknowledge financial support from the Research Foundation – Flanders (FWO), Grants 12M1315N and 1200216N. 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. We thank Prof. A. C. T. van Duin for sharing the ReaxFF code. | Approved | Most recent IF: 4.536 | ||
Call Number | c:irua:130677 | Serial | 4002 | ||
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Author | Huygh, S.; Bogaerts, A.; Neyts, E.C. | ||||
Title | How Oxygen Vacancies Activate CO2 Dissociation on TiO2 Anatase (001) | Type | A1 Journal article | ||
Year | 2016 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 120 | Issue | 120 | Pages | 21659-21669 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The adsorption, dissociation, and diffusion of CO2 on the anatase (001) surface was studied using DFT by means of the generalized gradient approximation using the Perdew−Burcke−Ernzerhof (PBE)-functional and applying corrections for long-range dispersion interactions. Different stable adsorption configurations were identified for the fully oxidized surface. The most stable adsorption configuration is the monodentated carbonate-like structure. Small energy barriers were identified for the conversion of a physisorbed to a chemisorbed configuration. CO2 dissociation is found to be unfeasible on the stoichiometric surface. The introduction of oxygen vacancy defects gives rise to new highly stable adsorption configurations with a stronger activation of the C−O bonds. This leads to the possibility of exothermic dissociation of CO2 with barriers up to 22.2 kcal/mol, corresponding to chemical lifetimes of less than 4 s at 300 K. These reactions cause a CO molecule to be formed, which will easily desorb, and the reduced surface to become oxidized. It is clear that oxygen vacancy defects play a key role in the catalytic activity of an anatase (001) surface. Oxygen vacancies play an important role in the dissociation of CO2 on the anatase (001) surface, and will play a significant role in complex problems, such as the catalytic conversion of CO2 to value-added chemicals. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000384626800055 | Publication Date | 2016-09-02 | |
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ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 49 | Open Access | |
Notes | Stijn Huygh is funded as an aspirant of the Research Foundation Flanders (FWO, project number 11C0115N). This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the UAntwerpen. | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @ c:irua:136164 | Serial | 4291 | ||
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Author | Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A. | ||||
Title | Influence of the Material Dielectric Constant on Plasma Generation inside Catalyst Pores | Type | A1 Journal article | ||
Year | 2016 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 120 | Issue | 120 | Pages | 25923-25934 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma catalysis is gaining increasing interest for various environmental applications, but the crucial question is whether plasma can be created inside catalyst pores and under which conditions. In practice, various catalytic support materials are used, with various dielectric constants. We investigate here the influence of the dielectric constant on the plasma properties inside catalyst pores and in the sheath in front of the pores, for various pore sizes. The calculations are performed by a two-dimensional fluid model for an atmospheric pressure dielectric barrier discharge in helium. The electron impact ionization rate, electron temperature, electron and ion density, as well as the potential distribution and surface charge density, are analyzed for a better understanding of the discharge behavior inside catalyst pores. The results indicate that, in a 100 μm pore, the electron impact ionization in the pore, which is characteristic for the plasma generation inside the pore, is greatly enhanced for dielectric constants below 300. Smaller pore sizes only yield enhanced ionization for smaller dielectric constants, i.e., up to εr = 200, 150, and 50 for pore sizes of 50, 30, and 10 μm. Thus, the most common catalyst supports, i.e., Al2O3 and SiO2, which have dielectric constants around εr = 8−11 and 4.2, respectively, should allow more easily that microdischarges can be formed inside catalyst pores, even for smaller pore sizes. On the other hand, ferroelectric materials with dielectric constants above 300 never seem to yield plasma enhancement inside catalyst pores, not even for 100 μm pore sizes. Furthermore, it is clear that the dielectric constant of the material has a large effect on the extent of plasma enhancement inside the catalyst pores, especially in the range between εr = 4 and εr = 200. The obtained results are explained in detail based on the surface charge density at the pore walls, and the potential distribution and electron temperature inside and above the pores. The results obtained with this model are important for plasma catalysis, as the production plasma species in catalyst pores might affect the catalyst properties, and thus improve the applications of plasma catalysis. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000388429100029 | Publication Date | 2016-11-17 | |
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 | 34 | Open Access | |
Notes | This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant G.0217.14N), the National Natural Science Foundation of China (Grant 11405019), and the China Postdoctoral Science Foundation (Grant 2015T80244). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the University of Antwerp. | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @ c:irua:138602 | Serial | 4319 | ||
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Author | Verlackt, C.C.W.; Van Boxem, W.; Dewaele, D.; Lemière, F.; Sobott, F.; Benedikt, J.; Neyts, E.C.; Bogaerts, A. | ||||
Title | Mechanisms of Peptide Oxidation by Hydroxyl Radicals: Insight at the Molecular Scale | Type | A1 Journal article | ||
Year | 2017 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 121 | Issue | 121 | Pages | 5787-5799 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Molecular dynamics (MD) simulations were performed to provide atomic scale insight in the initial interaction between hydroxyl radicals (OH) and peptide systems in solution. These OH radicals are representative reactive oxygen species produced by cold atmospheric plasmas. The use of plasma for biomedical applications is gaining increasing interest, but the fundamental mechanisms behind the plasma modifications still remain largely elusive. This study helps to gain more insight in the underlying mechanisms of plasma medicine but is also more generally applicable to peptide oxidation, of interest for other applications. Combining both reactive and nonreactive MD simulations, we are able to elucidate the reactivity of the amino acids inside the peptide systems and their effect on their structure up to 1 μs. Additionally, experiments were performed, treating the simulated peptides with a plasma jet. The computational results presented here correlate well with the obtained experimental data and highlight the importance of the chemical environment for the reactivity of the individual amino acids, so that specific amino acids are attacked in higher numbers than expected. Furthermore, the long time scale simulations suggest that a single oxidation has an effect on the 3D conformation due to an increase in hydrophilicity and intra- and intermolecular interactions. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000396969900037 | Publication Date | 2017-03-16 | |
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 | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G012413N ; | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @ c:irua:142202 | Serial | 4537 | ||
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Author | Mees, M.J.; Pourtois, G.; Neyts, E.C.; Thijsse, B.J.; Stesmans, A. | ||||
Title | Uniform-acceptance force-bias Monte Carlo method with time scale to study solid-state diffusion | Type | A1 Journal article | ||
Year | 2012 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 85 | Issue | 13 | Pages | 134301-134301,9 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Monte Carlo (MC) methods have a long-standing history as partners of molecular dynamics (MD) to simulate the evolution of materials at the atomic scale. Among these techniques, the uniform-acceptance force-bias Monte Carlo (UFMC) method [ G. Dereli Mol. Simul. 8 351 (1992)] has recently attracted attention [ M. Timonova et al. Phys. Rev. B 81 144107 (2010)] thanks to its apparent capacity of being able to simulate physical processes in a reduced number of iterations compared to classical MD methods. The origin of this efficiency remains, however, unclear. In this work we derive a UFMC method starting from basic thermodynamic principles, which leads to an intuitive and unambiguous formalism. The approach includes a statistically relevant time step per Monte Carlo iteration, showing a significant speed-up compared to MD simulations. This time-stamped force-bias Monte Carlo (tfMC) formalism is tested on both simple one-dimensional and three-dimensional systems. Both test-cases give excellent results in agreement with analytical solutions and literature reports. The inclusion of a time scale, the simplicity of the method, and the enhancement of the time step compared to classical MD methods make this method very appealing for studying the dynamics of many-particle systems. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000302290500001 | Publication Date | 2012-04-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 31 | Open Access | |
Notes | Approved | Most recent IF: 3.836; 2012 IF: 3.767 | |||
Call Number | UA @ lucian @ c:irua:97160 | Serial | 3809 | ||
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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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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
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 | Gogoi, A.; Neyts, E.C.; Peeters, F.M. | ||||
Title | Reduction-enhanced water flux through layered graphene oxide (GO) membranes stabilized with H3O+ and OH- ions | Type | A1 Journal article | ||
Year | 2024 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | |
Volume | 26 | Issue | 13 | Pages | 10265-10272 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Modelling and Simulation in Chemistry (MOSAIC) | ||||
Abstract | Graphene oxide (GO) is one of the most promising candidates for next generation of atomically thin membranes. Nevertheless, one of the major issues for real world application of GO membranes is their undesirable swelling in an aqueous environment. Recently, we demonstrated that generation of H3O+ and OH- ions (e.g., with an external electric field) in the interlayer gallery could impart aqueous stability to the layered GO membranes (A. Gogoi, ACS Appl. Mater. Interfaces, 2022, 14, 34946). This, however, compromises the water flux through the membrane. In this study, we report on reducing the GO nanosheets as a solution to this issue. With the reduction of the GO nanosheets, the water flux through the layered GO membrane initially increases and then decreases again beyond a certain degree of reduction. Here, two key factors are at play. Firstly, the instability of the H-bond network between water molecules and the GO nanosheets, which increases the water flux. Secondly, the pore size reduction in the interlayer gallery of the membranes, which decreases the water flux. We also observe a significant improvement in the salt rejection of the membranes, due to the dissociation of water molecules in the interlayer gallery. In particular, for the case of 10% water dissociation, the water flux through the membranes can be enhanced without altering its selectivity. This is an encouraging observation as it breaks the traditional tradeoff between water flux and salt rejection of a membrane. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001186465400001 | Publication Date | 2024-03-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1463-9076; 1463-9084 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.3 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 3.3; 2024 IF: 4.123 | |||
Call Number | UA @ admin @ c:irua:204792 | Serial | 9168 | ||
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Author | Neyts, E.C.; Brault, P. | ||||
Title | Molecular Dynamics Simulations for Plasma-Surface Interactions: Molecular Dynamics Simulations… | Type | A1 Journal article | ||
Year | 2017 | Publication | Plasma processes and polymers | Abbreviated Journal | Plasma Process Polym |
Volume | 14 | Issue | 14 | Pages | 1600145 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma-surface interactions are in general highly complex due to the interplay of many concurrent processes. Molecular dynamics simulations provide insight in some of these processes, subject to the accessible time and length scales, and the availability of suitable force fields. In this introductory tutorial-style review, we aim to describe the current capabilities and limitations of molecular dynamics simulations in this field, restricting ourselves to low-temperature nonthermal plasmas. Attention is paid to the simulation of the various fundamental processes occurring, including sputtering, etching, implantation, and deposition, as well as to what extent the basic plasma components can be accounted for, including ground state and excited species, electric fields, ions, photons, and electrons. A number of examples is provided, giving an bird’s eye overview of the current state of the field. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000393184600009 | Publication Date | 2016-09-07 | |
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 | 13 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 2.846 | |||
Call Number | PLASMANT @ plasmant @ c:irua:141758 | Serial | 4488 | ||
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Author | Van de Sompel, P.; Khalilov, U.; Neyts, E.C. | ||||
Title | Contrasting H-etching to OH-etching in plasma-assisted nucleation of carbon nanotubes | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
Volume | 125 | Issue | 14 | Pages | 7849-7855 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | To gain full control over the growth of carbon nanotubes (CNTs) using plasma-enhanced chemical vapor deposition (PECVD), a thorough understanding of the underlying plasma-catalyst mechanisms is required. Oxygen-containing species are often used as or added to the growth precursor gas, but these species also yield various radicals and ions, which may simultaneously etch the CNT during the growth. At present, the effect of these reactive species on the growth onset has not yet been thoroughly investigated. We here report on the etching mechanism of incipient CNT structures from OH and O radicals as derived from combined (reactive) molecular dynamics (MD) and force-bias Monte Carlo (tfMC) simulations. Our results indicate that the oxygen-containing radicals initiate a dissociation process. In particular, we show how the oxygen species weaken the interaction between the CNT and the nanocluster. As a result of this weakened interaction, the CNT closes off and dissociates from the cluster in the form of a fullerene. Beyond the specific systems studied in this work, these results are generically important in the context of PECVD-based growth of CNTs using oxygen-containing precursors. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000641307100032 | Publication Date | 2021-04-06 | |
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 | |
Impact Factor | 4.536 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 4.536 | |||
Call Number | UA @ admin @ c:irua:178393 | Serial | 7729 | ||
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Author | Elliott, J.A.; Shibuta, Y.; Amara, H.; Bichara, C.; Neyts, E.C. | ||||
Title | Atomistic modelling of CVD synthesis of carbon nanotubes and graphene | Type | A1 Journal article | ||
Year | 2013 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 5 | Issue | 15 | Pages | 6662-6676 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We discuss the synthesis of carbon nanotubes (CNTs) and graphene by catalytic chemical vapour deposition (CCVD) and plasma-enhanced CVD (PECVD), summarising the state-of-the-art understanding of mechanisms controlling their growth rate, chiral angle, number of layers (walls), diameter, length and quality (defects), before presenting a new model for 2D nucleation of a graphene sheet from amorphous carbon on a nickel surface. Although many groups have modelled this process using a variety of techniques, we ask whether there are any complementary ideas emerging from the different proposed growth mechanisms, and whether different modelling techniques can give the same answers for a given mechanism. Subsequently, by comparing the results of tight-binding, semi-empirical molecular orbital theory and reactive bond order force field calculations, we demonstrate that graphene on crystalline Ni(111) is thermodynamically stable with respect to the corresponding amorphous metal and carbon structures. Finally, we show in principle how a complementary heterogeneous nucleation step may play a key role in the transformation from amorphous carbon to graphene on the metal surface. We conclude that achieving the conditions under which this complementary crystallisation process can occur may be a promising method to gain better control over the growth processes of both graphene from flat metal surfaces and CNTs from catalyst nanoparticles. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000321675600003 | Publication Date | 2013-06-06 | |
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 | 52 | Open Access | |
Notes | Approved | Most recent IF: 7.367; 2013 IF: 6.739 | |||
Call Number | UA @ lucian @ c:irua:109231 | Serial | 200 | ||
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Author | Khalilov, U.; Pourtois, G.; van Duin, A.C.T.; Neyts, E.C. | ||||
Title | Hyperthermal oxidation of Si(100)2x1 surfaces : effect of growth temperature | Type | A1 Journal article | ||
Year | 2012 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 116 | Issue | 15 | Pages | 8649-8656 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Using reactive molecular dynamics simulations based on the ReaxFF potential, we studied the growth mechanism of ultrathin silica (SiO2) layers during hyperthermal oxidation as a function of temperature in the range 100-1300 K. Oxidation of Si(100){2 x 1} surfaces by both atomic and molecular oxygen was investigated for hyperthermal impact energies in the range of 1 to 5 eV. Two different growth mechanisms are found, corresponding to a low temperature oxidation and a high temperature one. The transition temperature between these mechanisms is estimated to be about 700 K. Also, the initial step of the Si oxidation process is analyzed in detail. Where possible, we validated our results with experimental and ab initio data, and good agreement was obtained. 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 | 000302924900035 | Publication Date | 2012-03-26 | |
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 | 32 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2012 IF: 4.814 | |||
Call Number | UA @ lucian @ c:irua:98259 | Serial | 1542 | ||
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Author | Neyts, E.C.; Khalilov, U.; Pourtois, G.; van Duin, A.C.T. | ||||
Title | Hyperthermal oxygen interacting with silicon surfaces : adsorption, implantation, and damage creation | 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 | 15 | Pages | 4818-4823 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Using reactive molecular dynamics simulations, we have investigated the effect of single-impact, low-energy (thermal-100 eV) bombardment of a Si(100){2 × 1} surface by atomic and molecular oxygen. Penetration probability distributions, as well as defect formation distributions, are presented as a function of the impact energy for both species. It is found that at low impact energy, defects are created chemically due to the chemisorption process in the top layers of the surface, while at high impact energy, additional defects are created by a knock-on displacement of Si. These results are of particular importance for understanding device performances of silica-based microelectronic and photovoltaic devices. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000288401200060 | Publication Date | 2011-03-02 | |
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 | 28 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2011 IF: 4.805 | |||
Call Number | UA @ lucian @ c:irua:89858 | Serial | 1543 | ||
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Author | Khalilov, U.; Bogaerts, A.; Neyts, E.C. | ||||
Title | Microscopic mechanisms of vertical graphene and carbon nanotube cap nucleation from hydrocarbon growth precursors | Type | A1 Journal article | ||
Year | 2014 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 6 | Issue | 15 | Pages | 9206-9214 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Controlling and steering the growth of single walled carbon nanotubes is often believed to require controlling of the nucleation stage. Yet, little is known about the microscopic mechanisms governing the nucleation from hydrocarbon molecules. Specifically, we address here the dehydrogenation of hydrocarbon molecules and the formation of all-carbon graphitic islands on metallic nanoclusters from hydrocarbon molecules under conditions typical for carbon nanotube growth. Employing reactive molecular dynamics simulations, we demonstrate for the first time that the formation of a graphitic network occurs through the intermediate formation of vertically oriented, not fully dehydrogenated graphitic islands. Upon dehydrogenation of these vertical graphenes, the islands curve over the surface, thereby forming a carbon network covering the nanoparticle. The results indicate that controlling the extent of dehydrogenation offers an additional parameter to control the nucleation of carbon nanotubes. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000339861500103 | Publication Date | 2014-05-27 | |
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 | 21 | Open Access | |
Notes | Approved | Most recent IF: 7.367; 2014 IF: 7.394 | |||
Call Number | UA @ lucian @ c:irua:117950 | Serial | 2027 | ||
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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 | 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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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 | Kovács, A.; Billen, P.; Cornet, I.; Wijnants, M.; Neyts, E.C. | ||||
Title | Modeling the physicochemical properties of natural deep eutectic solvents : a review | Type | A1 Journal article | ||
Year | 2020 | Publication | Chemsuschem | Abbreviated Journal | Chemsuschem |
Volume | 13 | Issue | 15 | Pages | 3789-3804 |
Keywords | A1 Journal article; Engineering sciences. Technology; Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Biochemical Wastewater Valorization & Engineering (BioWaVE) | ||||
Abstract | Natural deep eutectic solvents (NADES) are mixtures of naturally derived compounds with a significantly decreased melting point due to the specific interactions among the constituents. NADES have benign properties (low volatility, flammability, toxicity, cost) and tailorable physicochemical properties (by altering the type and molar ratio of constituents), hence they are often considered as a green alternative to common organic solvents. Modeling the relation between their composition and properties is crucial though, both for understanding and predicting their behavior. Several efforts were done to this end, yet this review aims at structuring the present knowledge as an outline for future research. First, we reviewed the key properties of NADES and relate them to their structure based on the available experimental data. Second, we reviewed available modeling methods applicable to NADES. At the molecular level, density functional theory and molecular dynamics allow interpreting density differences and vibrational spectra, and computation of interaction energies. Additionally, properties at the level of the bulk media can be explained and predicted by semi-empirical methods based on ab initio methods (COSMO-RS) and equation of state models (PC-SAFT). Finally, methods based on large datasets are discussed; models based on group contribution methods and machine learning. A combination of bulk media and dataset modeling allows qualitative prediction and interpretation of phase equilibria properties on the one hand, and quantitative prediction of melting point, density, viscosity, surface tension and refractive indices on the other hand. In our view, multiscale modeling, combining the molecular and macroscale methods, will strongly enhance the predictability of NADES properties and their interaction with solutes, yielding truly tailorable solvents to accommodate (bio)chemical reactions. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000541499100001 | Publication Date | 2020-05-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1864-5631 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.4 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 8.4; 2020 IF: 7.226 | |||
Call Number | UA @ admin @ c:irua:168851 | Serial | 6770 | ||
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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 | Grubova, I.Y.; Surmeneva, M.A.; Huygh, S.; Surmenev, R.A.; Neyts, E.C. | ||||
Title | Effects of silicon doping on strengthening adhesion at the interface of the hydroxyapatite-titanium biocomposite : a first-principles study | Type | A1 Journal article | ||
Year | 2019 | Publication | Computational materials science | Abbreviated Journal | Comp Mater Sci |
Volume | 159 | Issue | 159 | Pages | 228-234 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this paper we employ first-principles calculations to investigate the effect of substitutional Si doping in the amorphous calcium-phosphate (a-HAP) structure on the work of adhesion, integral charge transfer, charge density difference and theoretical tensile strengths between an a-HAP coating and amorphous titanium dioxide (a-TiO2) substrate systemically. Our calculations demonstrate that substitution of a P atom by a Si atom in a-HAP (a-Si-HAP) with the creation of OH-vacancies as charge compensation results in a significant increase of the bonding strength of the coating to the substrate. The work of adhesion of the optimized Si-doped interfaces reaches a value of up to -2.52 J m(-2), which is significantly higher than for the stoichiometric a-HAP/a-TiO2. Charge density difference analysis indicates that the dominant interactions at the interface have significant covalent character, and in particular two Ti-O and three Ca-O bonds are formed for a-Si-HAP/a-TiO2 and one Ti-O and three Ca-O bonds for a-HAP/a-TiO2. From the stress-strain curve, the Young's modulus of a-Si-HAP/a-TiO2 is calculated to be about 25% higher than that of the a-HAP/a-TiO2, and the yielding stress is about 2 times greater than that of the undoped model. Our calculations therefore demonstrate that the presence of Si in the a-HAP structure strongly alters not only the bioactivity and resorption rates, but also the mechanical properties of the a-HAP/a-TiO2 interface. The results presented here provide an important theoretical insight into the nature of the chemical bonding at the a-HAP/a-TiO2 interface, and are particularly significant for the practical medical applications of HAP-based biomaterials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000457856900023 | Publication Date | 2018-12-18 | |
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 | 2.292 | Times cited | 1 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 2.292 | |||
Call Number | UA @ admin @ c:irua:157480 | Serial | 5272 | ||
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Author | Neyts, E.C.; van Duin, A.C.T.; Bogaerts, A. | ||||
Title | Formation of single layer graphene on nickel under far-from-equilibrium high flux conditions | Type | A1 Journal article | ||
Year | 2013 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 5 | Issue | 16 | Pages | 7250-7255 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We investigate the theoretical possibility of single layer graphene formation on a nickel surface at different substrate temperatures under far-from-equilibrium high precursor flux conditions, employing state-of-the-art hybrid reactive molecular dynamics/uniform acceptance force bias Monte Carlo simulations. It is predicted that under these conditions, the formation of a single layer graphene-like film may proceed through a combined depositionsegregation mechanism on a nickel substrate, rather than by pure surface segregation as is typically observed for metals with high carbon solubility. At 900 K and above, nearly continuous graphene layers are obtained. These simulations suggest that single layer graphene deposition is theoretically possible on Ni under high flux conditions. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000322315600019 | Publication Date | 2013-04-26 | |
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 | 25 | Open Access | |
Notes | Approved | Most recent IF: 7.367; 2013 IF: 6.739 | |||
Call Number | UA @ lucian @ c:irua:109249 | Serial | 1264 | ||
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