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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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| 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 | Nematollahi, P.; Ma, H.; Schneider, W.F.; Neyts, E.C. | ||||
| Title | DFT and microkinetic comparison of ru-doped porphyrin-like graphene and nanotubes toward catalytic formic acid decomposition and formation | Type | A1 Journal article | ||
| Year | 2021 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 125 | Issue | 34 | Pages | 18673-18683 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Immobilization of single metal atoms on a solid host opens numerous possibilities for catalyst designs. If that host is a two-dimensional sheet, sheet curvature becomes a design parameter potentially complementary to host and metal composition. Here, we use a combination of density functional theory calculations and microkinetic modeling to compare the mechanisms and kinetics of formic acid decomposition and formation, chosen for their relevance as a potential hydrogen storage medium, over single Ru atoms anchored to pyridinic nitrogen in a planar graphene flake (RuN4-G) and curved carbon nanotube (RuN4-CNT). Activation barriers are lowered and the predicted turnover frequencies are increased over RuN4-CNT relative to RuN4-CNT. The results highlight the potential of curvature control as a means to achieve high performance and robust catalysts. | ||||
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| Language | Wos | 000693413400013 | Publication Date | 2021-08-22 | |
| 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 | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 4.536 | |||
| Call Number | UA @ admin @ c:irua:181538 | Serial | 7805 | ||
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| Author | van ‘t Veer, K.; Engelmann, Y.; Reniers, F.; Bogaerts, A. | ||||
| Title | Plasma-Catalytic Ammonia Synthesis in a DBD Plasma: Role of Microdischarges and Their Afterglows | Type | A1 Journal article | ||
| Year | 2020 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 124 | Issue | 42 | Pages | 22871-22883 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Movement Antwerp (MOVANT) | ||||
| Abstract | Plasma-catalytic ammonia synthesis is receiving ever increasing attention, especially in packed bed dielectric barrier discharge (DBD) reactors. The latter typically operate in the filamentary regime when used for gas conversion applications. While DBDs are in principle well understood and already applied in the industry, the incorporation of packing materials and catalytic surfaces considerably adds to the complexity of the plasma physics and chemistry governing the ammonia formation. We employ a plasma kinetics model to gain insights into the ammonia formation mechanisms, paying special attention to the role of filamentary microdischarges and their afterglows. During the microdischarges, the synthesized ammonia is actually decomposed, but the radicals created upon electron impact dissociation of N2 and H2 and the subsequent catalytic reactions cause a net ammonia gain in the afterglows of the microdischarges. Under our plasma conditions, electron impact dissociation of N2 in the gas phase followed by the adsorption of N atoms is identified as a rate-limiting step, instead of dissociative adsorption of N2 on the catalyst surface. Both elementary Eley−Rideal and Langmuir−Hinshelwood reaction steps can be found important in plasma-catalytic NH3 synthesis. | ||||
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| Language | Wos | 000585970300002 | Publication Date | 2020-10-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.7 | Times cited | Open Access | OpenAccess | |
| Notes | Fonds Wetenschappelijk Onderzoek, 30505023 GoF9618n ; Fonds De La Recherche Scientifique – FNRS, 30505023 GoF9618n ; H2020 European Research Council, 810182 ;This research was supported by the Excellence of Science FWOFNRS project (FWO grant ID GoF9618n, EOS ID 30505023) and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no 810182-SCOPE ERC Synergy project). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. The authors would also like to thank Järi Van den Hoek and Dr. Yury Gorbanev for providing the experimentally measured electrical characteristics and Dr. Fatme Jardali for creating the TOC graphics. | Approved | Most recent IF: 3.7; 2020 IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:173587 | Serial | 6428 | ||
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| Author | Michiels, R.; Engelmann, Y.; Bogaerts, A. | ||||
| Title | Plasma Catalysis for CO2Hydrogenation: Unlocking New Pathways toward CH3OH | Type | A1 Journal article | ||
| Year | 2020 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 124 | Issue | 47 | Pages | 25859-25872 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Movement Antwerp (MOVANT) | ||||
| Abstract | We developed a microkinetic model to reveal the effects of plasma-generated radicals, intermediates, and vibrationally excited species on the catalytic hydrogenation of CO2 to CH3OH on a Cu(111) surface. As a benchmark, we first present the mechanisms of thermal catalytic CH3OH formation. Our model predicts that the reverse water-gas shift reaction followed by CO hydrogenation, together with the formate path, mainly contribute to CH3OH formation in thermal catalysis. Adding plasma-generated radicals and intermediates results in a higher CH3OH turnover frequency (TOF) by six to seven orders of magnitude, showing the potential of plasma-catalytic CO2 hydrogenation into CH3OH, in accordance with the literature. In addition, CO2 vibrational excitation further increases the CH3OH TOF, but the effect is limited due to relatively low vibrational temperatures under typical plasma catalysis conditions. The predicted increase in CH3OH formation by plasma catalysis is mainly attributed to the increased importance of the formate path. In addition, the conversion of plasma-generated CO to HCO* and subsequent HCOO* or H2CO* formation contribute to CH3OH formation. Both pathways bypass the HCOO* formation from CO2, which is the main bottleneck in the process. Hence, our model points toward the important role of CO, but also O, OH, and H radicals, as they influence the reactions that consume CO2 and CO. In addition, our model reveals that the H pressure should not be smaller than ca. half of the O pressure in the plasma as this would cause O* poisoning, which would result in very small product TOFs. Thus, plasma conditions should be targeted with a high CO and H content as this is favorable for CH3OH formation, while the O content should be minimized. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000595545800023 | Publication Date | 2020-11-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.7 | Times cited | Open Access | Not_Open_Access: Available from 15.07.2021 | |
| Notes | Universiteit Antwerpen; Fonds Wetenschappelijk Onderzoek, 1114921N ; H2020 European Research Council, 810182 ; We acknowledge the financial support from the Fund for Scientific Research (FWO-Vlaanderen; grant ID 1114921N) and from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 810182 − SCOPE ERC Synergy project) as well as from the DOC-PRO3 and the TOPBOF projects of the University of Antwerp. | Approved | Most recent IF: 3.7; 2020 IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:173864 | Serial | 6443 | ||
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| Author | Loenders, B.; Engelmann, Y.; Bogaerts, A. | ||||
| Title | Plasma-Catalytic Partial Oxidation of Methane on Pt(111): A Microkinetic Study on the Role of Different Plasma Species | Type | A1 Journal article | ||
| Year | 2021 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 125 | Issue | 5 | Pages | 2966-2983 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Movement Antwerp (MOVANT) | ||||
| Abstract | We use microkinetic modeling to examine the potential of plasma-catalytic partial oxidation (POX) of CH4 as a promising new approach to produce oxygenates. We study how different plasma species affect POX of CH4 on the Pt(111) surface, and we discuss the associated kinetic and mechanistic changes. We discuss the effect of vibrationally excited CH4 and O2, as well as plasma-generated radicals and stable intermediates. Our results show that vibrational excitation enhances the turnover frequency (TOF) of catalytic CH4 dissociation and has good potential for improving the selectivities toward CH3OH, HCOOH, and C2 hydrocarbons. Nevertheless, when also considering plasma-generated radicals, we find that these species mainly govern the surface chemistry. Additionally, we find that plasma-generated radicals and stable intermediates enhance the TOFs of COx and oxygenates, increase the selectivity toward oxygenates, and make the formation of HCOOH more significant on Pt(111). We also briefly illustrate the potential impact of Eley−Rideal reactions that involve plasma-generated radicals. Finally, we reveal how various radicals affect the catalyst surface chemistry and we link this to the formation of different products. This allows us to make suggestions on how the plasma composition should be altered to improve the formation of desired products. | ||||
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| Language | Wos | 000619760700017 | Publication Date | 2021-02-11 | |
| 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 | Open Access | OpenAccess | |
| Notes | Universiteit Antwerpen; Fonds Wetenschappelijk Onderzoek, S001619N ; H2020 European Research Council, 810182 ; We thank Tom Butterworth for the interesting discussions regarding the calculation of the vibrational populations of methane and for taking the time to share his thoughts and experiences on the matter. This research is supported by the FWO-SBO project PLASMACATDesign (grant number S001619N). We also acknowledge financial support from the TOP-BOF project of the University of Antwerp and from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Program (grant agreement no. 810182SCOPE ERC Synergy project). The 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), and the University of Antwerp. | Approved | Most recent IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:175873 | Serial | 6672 | ||
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| Author | Borah, R.; Verbruggen, S.W. | ||||
| Title | Coupled plasmon modes in 2D gold nanoparticle clusters and their effect on local temperature control | 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 | 50 | Pages | 30594-30603 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | Assemblies of closely separated gold nanoparticles exhibit a strong collective plasmonic response due to coupling of the plasmon modes of the individual nanostructures. In the context of self-assembly of nanoparticles, close-packed two-dimensional (2D) clusters of spherical nanoparticles present an important composite system that promises numerous applications. The present study probes the collective plasmonic characteristics and resulting photothermal behavior of close-packed 2D Au nanoparticle clusters to delineate the effects of the cluster size, interparticle distance, and particle size. Smaller nanoparticles (20 and 40 nm in diameter) that exhibit low individual scattering and high absorption were considered for their relevance to photothermal applications. In contrast to typical literature studies, the present study compares the optical response of clusters of different sizes ranging from a single nanoparticle up to large assemblies of 61 nanoparticles. Increasing the cluster size induces significant changes to the spectral position and optophysical characteristics. Based on the model outcome, an optimal cluster size for maximum absorption per nanoparticle is also determined for enhanced photothermal effects. The effect of the particle size and interparticle distance is investigated to elucidate the nature of interaction in terms of near-field and far-field coupling. The photothermal effect resulting from absorption is compared for different cluster sizes and interparticle distances considering a homogeneous water medium. A strong dependence of the steady-state temperature of the nanoparticles on the cluster size, particle position in the cluster, incident light polarization, and interparticle distance provides new physical insight into the local temperature control of plasmonic nanostructures. | ||||
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| Language | Wos | 000503919500061 | Publication Date | 2019-11-20 | |
| 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 | Open Access | ||
| Notes | Approved | Most recent IF: 4.536 | |||
| Call Number | UA @ admin @ c:irua:164530 | Serial | 5938 | ||
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| Author | Verbruggen, S.W.; Keulemans, M.; Martens, J.A.; Lenaerts, S. | ||||
| Title | Predicting the surface plasmon resonance wavelength of gold-silver alloy nanoparticles | Type | A1 Journal article | ||
| Year | 2013 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
| Volume | 117 | Issue | 37 | Pages | 19142-19145 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | Gold-silver alloy nanoparticles display surface plasmon resonance (SPR) over a broad range of the UV-vis spectrum. We propose a model to predict the SPR wavelength of gold-silver alloy colloids based on the combined effect of alloy composition and particle size. The SPR wavelength is derived from extinction spectra simulated using available experimental dielectric constant data and accounts for particle size by applying Mie theory. Comparison of calculated values with experimental data evidences the accuracy of the model. The new SPR wavelength estimation tool will be of particular interest for developing dedicated bimetallic plasmonic nanostructures. | ||||
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| Language | Wos | 000330162600042 | Publication Date | 2013-08-27 | |
| 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 | 51 | Open Access | |
| Notes | ; S.W.V. acknowledges the Research Foundation of Flanders (FWO) for financial support. JAM. acknowledges the Flemish government for long-term structural funding (Methusalem). ; | Approved | Most recent IF: 4.536; 2013 IF: 4.835 | ||
| Call Number | UA @ admin @ c:irua:114837 | Serial | 5985 | ||
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| Author | Borah, R.; Verbruggen, S.W. | ||||
| Title | Silver–Gold Bimetallic Alloy versus Core–Shell Nanoparticles: Implications for Plasmonic Enhancement and Photothermal Applications | Type | A1 Journal article | ||
| Year | 2020 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | Issue | Pages | acs.jpcc.0c02630 | ||
| Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | Bimetallic plasmonic nanoparticles enable tuning of the optical response and chemical stability by variation of the composition. The present numerical simulation study compares Ag–Au alloy, Ag@Au core–shell, and Au@Ag core–shell bimetallic plasmonic nanoparticles of both spherical and anisotropic (nanotriangle and nanorods) shapes. By studying both spherical and anisotropic (with LSPR in the near-infrared region) shapes, cases with and without interband transitions of Au can be decoupled. Explicit comparisons are facilitated by numerical models supported by careful validation and examination of optical constants of Au–Ag alloys reported in the literature. Although both Au–Ag core–shell and alloy nanoparticles exhibit an intermediary optical response between that of pure Ag and Au nanoparticles, there are noticeable differences in the spectral characteristics. Also, the effect of the bimetallic constitution in anisotropic nanoparticles is starkly different from that in spherical nanoparticles due to the absence of Au interband transitions in the former case. In general, the improved chemical stability of Ag nanoparticles by incorporation of Au comes with a cost of reduction in plasmonic enhancement, also applicable to anisotropic nanoparticles with a weaker effect. A photothermal heat transfer study confirms that increased absorption by the incorporation of Au in spherical Ag nanoparticles also results in an increased steady-state temperature. On the other hand, anisotropic nanoparticles are inherently better absorbers and hence better photothermal sources, and their photothermal properties are apparently not strongly affected by the incorporation of one metal in the other. This study of the optical/spectral and photothermal characteristics of bimetallic Au–Ag alloy versus core–shell nanoparticles provides detailed physical insight for development of new taylor-made plasmonic nanostructures. | ||||
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| Language | Wos | 000538758700039 | Publication Date | 2020-05-19 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.7 | Times cited | Open Access | ||
| Notes | Universiteit Antwerpen, DOCPRO4 Rituraj Borah ; | Approved | Most recent IF: 3.7; 2020 IF: 4.536 | ||
| Call Number | DuEL @ duel @c:irua:169223 | Serial | 6367 | ||
| Permanent link to this record | |||||
| Author | Borah, R.; Verbruggen, S.W. | ||||
| Title | Silver–Gold Bimetallic Alloy versus Core–Shell Nanoparticles: Implications for Plasmonic Enhancement and Photothermal Applications | Type | A1 Journal article | ||
| Year | 2020 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | Issue | Pages | acs.jpcc.0c02630 | ||
| Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | Bimetallic plasmonic nanoparticles enable tuning of the optical response and chemical stability by variation of the composition. The present numerical simulation study compares Ag–Au alloy, Ag@Au core–shell, and Au@Ag core–shell bimetallic plasmonic nanoparticles of both spherical and anisotropic (nanotriangle and nanorods) shapes. By studying both spherical and anisotropic (with LSPR in the near-infrared region) shapes, cases with and without interband transitions of Au can be decoupled. Explicit comparisons are facilitated by numerical models supported by careful validation and examination of optical constants of Au–Ag alloys reported in the literature. Although both Au–Ag core–shell and alloy nanoparticles exhibit an intermediary optical response between that of pure Ag and Au nanoparticles, there are noticeable differences in the spectral characteristics. Also, the effect of the bimetallic constitution in anisotropic nanoparticles is starkly different from that in spherical nanoparticles due to the absence of Au interband transitions in the former case. In general, the improved chemical stability of Ag nanoparticles by incorporation of Au comes with a cost of reduction in plasmonic enhancement, also applicable to anisotropic nanoparticles with a weaker effect. A photothermal heat transfer study confirms that increased absorption by the incorporation of Au in spherical Ag nanoparticles also results in an increased steady-state temperature. On the other hand, anisotropic nanoparticles are inherently better absorbers and hence better photothermal sources, and their photothermal properties are apparently not strongly affected by the incorporation of one metal in the other. This study of the optical/spectral and photothermal characteristics of bimetallic Au–Ag alloy versus core–shell nanoparticles provides detailed physical insight for development of new taylor-made plasmonic nanostructures. | ||||
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| Language | Wos | 000538758700039 | Publication Date | 2020-05-19 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.7 | Times cited | Open Access | ||
| Notes | Universiteit Antwerpen, DOCPRO4 Rituraj Borah ; | Approved | Most recent IF: 3.7; 2020 IF: 4.536 | ||
| Call Number | DuEL @ duel @c:irua:169223 | Serial | 6368 | ||
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| Author | Wendelen, W.; Dzhurakhalov, A.A.; Peeters, F.M.; Bogaerts, A. | ||||
| Title | Combined molecular dynamics: continuum study of phase transitions in bulk metals under ultrashort pulsed laser irradiation | Type | A1 Journal article | ||
| Year | 2010 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
| Volume | 114 | Issue | 12 | Pages | 5652-5660 |
| Keywords |
A1 Journal article; Integrated Molecular Plant Physiology Research (IMPRES); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | The phase transition processes induced by ultrashort, 100 fs pulsed laser irradiation of Au, Cu, and Ni are studied by means of a combined atomistic-continuum approach. A moderately low absorbed laser fluence range, from 200 to 600 J/m2 is considered to study phase transitions by means of a local and a nonlocal order parameter. At low laser fluences, the occurrence of layer-by-layer evaporation has been observed, which suggests a direct solid to vapor transition. The calculated amount of molten material remains very limited under the conditions studied, especially for Ni. Therefore, our results show that a kinetic equation that describes a direct solid to vapor transition might be the best approach to model laser-induced phase transitions by continuum models. Furthermore, the results provide more insight into the applicability of analytical superheating theories that were implemented in continuum models and help the understanding of nonequilibrium phase transitions. | ||||
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| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000275855600044 | Publication Date | 2010-01-26 | |
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| ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 2 | Open Access | |
| Notes | ; A.D. gratefully acknowledges Professor M. Hot (ULB, Brussels) for the basic MD-code that was modified further for the laser-induced melting processes. W.W, and A.D. are thankful to Professor L.V. Zhigilei for useful discussions and advices. The calculations were performed on the CALCUA computing facility of the University of Antwerp. This work was supported by the Belgian Science Policy (IAP). ; | Approved | Most recent IF: 4.536; 2010 IF: 4.524 | ||
| Call Number | UA @ lucian @ c:irua:81391 | Serial | 402 | ||
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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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| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000297947700050 | Publication Date | 2011-11-16 | |
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| 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 | 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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| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000288401200060 | Publication Date | 2011-03-02 | |
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| 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 | Delabie, A.; Sioncke, S.; Rip, J.; van Elshocht, S.; Caymax, M.; Pourtois, G.; Pierloot, K. | ||||
| Title | Mechanisms for the trimethylaluminum reaction in aluminum oxide atomic layer deposition on sulfur passivated germanium | 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 | 35 | Pages | 17523-17532 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Germanium combined with high-κ dielectrics is investigated for the next generations of CMOS devices. Therefore, we study reaction mechanisms for Al2O3 atomic layer deposition on sulfur passivated Ge using calculations based on density functional theory and total reflection X-ray fluorescence (TXRF). TXRF indicates 6 S/nm2 and 4 Al/nm2 after the first TMA/H2O reaction cycle, and growth inhibition from the second reaction cycle on. Calculations are performed on molecular clusters representing −GeSH surface sites. The calculations confirm that the TMA reaction does not affect the S content. On fully SH-terminated Ge, TMA favorably reacts with up to three −GeSH sites, resulting in a near tetrahedral Al coordination. Electron deficient structures with a GeS site shared between two Al atoms are proposed. The impact of the cluster size on the structures and reaction energetics is systematically investigated. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000294386000037 | Publication Date | 2011-08-01 | |
| 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 | 9 | Open Access | |
| Notes | Approved | Most recent IF: 4.536; 2011 IF: 4.805 | |||
| Call Number | UA @ lucian @ c:irua:91714 | Serial | 1980 | ||
| Permanent link to this record | |||||
| Author | Neyts, E.C.; Bogaerts, A. | ||||
| Title | Numerical study of the size-dependent melting mechanisms of nickel nanoclusters | Type | A1 Journal article | ||
| Year | 2009 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
| Volume | 113 | Issue | 7 | Pages | 2771-2776 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Molecular dynamics simulations were used to investigate the size-dependent melting mechanism of nickel nanoclusters of various sizes. The melting process was monitored by the caloric curve, the overall cluster Lindemann index, and the atomic Lindemann index. Size-dependent melting temperatures were determined, and the correct linear dependence on inverse diameter was recovered. We found that the melting mechanism gradually changes from dynamic coexistence melting to surface melting with increasing cluster size. These findings are of importance in better understanding carbon nanotube growth by catalytic chemical vapor deposition as the phase state of the catalyst nanoparticle codetermines the growth mechanism. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | Publication Date | 0000-00-00 | ||
| 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 | Open Access | ||
| Notes | Approved | Most recent IF: 4.536; 2009 IF: 4.224 | |||
| Call Number | UA @ lucian @ c:irua:76495 | Serial | 2410 | ||
| Permanent link to this record | |||||
| Author | Kolev, I.; Bogaerts, A. | ||||
| Title | Numerical study of the sputtering in a dc magnetron | Type | A1 Journal article | ||
| Year | 2009 | Publication | Journal of vacuum science and technology: A: vacuum surfaces and films | Abbreviated Journal | J Phys Chem C |
| Volume | 27 | Issue | 1 | Pages | 20-28 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Molecular dynamics simulations were used to investigate the size-dependent melting mechanism of nickel nanoclusters of various sizes. The melting process was monitored by the caloric curve, the overall cluster Lindemann index, and the atomic Lindemann index. Size-dependent melting temperatures were determined, and the correct linear dependence on inverse diameter was recovered. We found that the melting mechanism gradually changes from dynamic coexistence melting to surface melting with increasing cluster size. These findings are of importance in better understanding carbon nanotube growth by catalytic chemical vapor deposition as the phase state of the catalyst nanoparticle codetermines the growth mechanism. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000263299600018 | Publication Date | 2009-02-03 | |
| 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 | 66 | Open Access | |
| Notes | Approved | Most recent IF: 4.536; 2009 IF: 4.224 | |||
| Call Number | UA @ lucian @ c:irua:71634 | Serial | 2411 | ||
| Permanent link to this record | |||||
| Author | Nourbakhsh, A.; Cantoro, M.; Klekachev, A.V.; Pourtois, G.; Vosch, T.; Hofkens, J.; van der Veen, M.H.; Heyns, M.M.; de Gendt, S.; Sels, B.F. | ||||
| Title | Single layer vs bilayer graphene : a comparative study of the effects of oxygen plasma treatment on their electronic and optical properties | 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 | 33 | Pages | 16619-16624 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | This contribution presents the effects of a mild O2 plasma treatment on the structural, optical, and electrical properties of single-layer (SLG) and bilayer graphene (BLG). Unexpectedly, we observe only photoluminescence in the SLG parts of a graphene flake composed of regions of various thickness upon O2 plasma treatment, whereas the BLG and few-layer graphene (FLG) parts remain optically unchanged. Confirmed with X-ray photoelectron spectroscopy (XPS) that O2 plasma induces epoxide and hydroxyl-like groups in graphene, density functional theory (DFT) calculations are carried out on representative epoxidized and hydroxylated SLG and BLG models to predict density of states (DOS) and band structures. Sufficiently oxidized SLG shows a bandgap and thus loss of semimetallic behavior, while oxidized BLG maintains its semimetallic behavior even at high oxygen density in agreement with the results of the photoluminescence spectroscopy (PL) experiments. DFT calculations confirm that the Fermi velocity in epoxidized BLG is remarkably comparable with that of pristine SLG, pointing to a similarity of electronic band structure. The similarity is also experimentally demonstrated by the electrical characterization of a plasma-treated BLG-FET. As expected from the electronegative oxygen adatoms in the graphene, epoxidized BLG presents conductive features typical of hole doping. Moreover, the electrical characteristics suggest band structures closely related to that of epoxidized graphene while deviating from that of hydroxylated graphene. Finally, upon O2 plasma treatment of BLG, the four-component 2D peak around 2700 cm1 in the Raman spectrum evolves into a single Lorentzian line, very like the 2D peak of pristine SLG. Summarizing, the data in this contribution recommend that a controlled O2 plasma treatment, which is compatible with CMOS process flow in contrast to wet chemical oxidation methods, provides an efficient and valuable technique to exploit the transport properties of the bottom layer of BLG. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000294077000047 | Publication Date | 2011-06-24 | |
| 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 | 46 | Open Access | |
| Notes | Approved | Most recent IF: 4.536; 2011 IF: 4.805 | |||
| Call Number | UA @ lucian @ c:irua:91715 | Serial | 3024 | ||
| Permanent link to this record | |||||
| 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 | ||
| Permanent link to this record | |||||
| Author | Berthelot, A.; Bogaerts, A. | ||||
| Title | Modeling of CO2Splitting in a Microwave Plasma: How to Improve the Conversion and Energy Efficiency | 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 | 8236-8251 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Microwave plasmas are one of the most promising techniques for CO2 conversion into value-added chemicals and fuels since they are very energy efficient. Nevertheless, experiments show that this high energy efficiency is only reached at low pressures and significantly drops toward atmospheric pressure, which is a clear limitation for industrial applications. In this paper, we use a zerodimensional reaction kinetics model to simulate a CO2 microwave plasma in a pressure range from 50 mbar to 1 bar, in order to evaluate the reasons for this decrease in energy efficiency at atmospheric pressure. The code includes a detailed description of the vibrational kinetics of CO2, CO, and O2 as well as the energy exchanges between them because the vibrational kinetics is known to be crucial for energy efficient CO2 splitting. First, we use a self-consistent gas temperature calculation in order to assess the key performance indicators for CO2 splitting, i.e., the CO2 conversion and corresponding energy efficiency. Our results indicate that lower pressures and higher power densities lead to more vibrational excitation, which is beneficial for the conversion. We also demonstrate the key role of the gas temperature. The model predicts the highest conversion and energy efficiencies at pressures around 300 mbar, which is in agreement with experiments from the literature. We also show the beneficial aspect of fast gas cooling in the afterglow at high pressure. In a second step, we study in more detail the effects of pressure, gas temperature, and power density on the vibrational distribution function and on the dissociation and recombination mechanisms of CO2, which define the CO2 splitting efficiency. This study allows us to identify the limiting factors of CO2 conversion and to propose potential solutions to improve the process. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000400039300002 | Publication Date | 2017-04-20 | |
| 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 | 47 | Open Access | OpenAccess |
| Notes | Federaal Wetenschapsbeleid; | Approved | Most recent IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @ c:irua:142809 | Serial | 4567 | ||
| Permanent link to this record | |||||
| Author | Trenchev, G.; Kolev, S.; Wang, W.; Ramakers, M.; Bogaerts, A. | ||||
| Title | CO2Conversion in a Gliding Arc Plasmatron: Multidimensional Modeling for Improved Efficiency | 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 | 44 | Pages | 24470-24479 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | The gliding arc plasmatron (GAP) is a highly efficient atmospheric plasma source, which is very promising for CO2 conversion applications. To understand its operation principles and to improve its application, we present here comprehensive modeling results, obtained by means of computational fluid dynamics simulations and plasma modeling. Because of the complexity of the CO2 plasma, a full 3D plasma model would be computationally impractical. Therefore, we combine a 3D turbulent gas flow model with a 2D plasma and gas heating model in order to calculate the plasma parameters and CO2 conversion characteristics. In addition, a complete 3D gas flow and plasma model with simplified argon chemistry is used to evaluate the gliding arc evolution in space and time. The calculated values are compared with experimental data from literature as much as possible in order to validate the model. The insights obtained in this study are very helpful for improving the application of CO2 conversion, as they allow us to identify the limiting factors in the performance, based on which solutions can be provided on how to further improve the capabilities of CO2 conversion in the GAP. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000415140400014 | Publication Date | 2017-11-09 | |
| 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 | Open Access | OpenAccess | |
| Notes | H2020 Marie Sklodowska-Curie Actions, 657304 ; Fonds Wetenschappelijk Onderzoek, 11U5316N G038316N ; | Approved | Most recent IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:147193 | Serial | 4765 | ||
| Permanent link to this record | |||||
| Author | Huygh, S.; Bogaerts, A.; Bal, K.M.; Neyts, E.C. | ||||
| Title | High Coke Resistance of a TiO2Anatase (001) Catalyst Surface during Dry Reforming of Methane | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 122 | Issue | 17 | Pages | 9389-9396 |
| Keywords |
A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | The resistance of a TiO2 anatase (001) surface to coke formation was studied in the context of dry reforming of methane using density functional theory (DFT) calculations. As carbon atoms act as precursors for coke formation, the resistance to coke formation can be measured by the carbon coverage of the surface. This is related to the stability of different CHx (x = 0−3) species and their rate of hydrogenation and dehydrogenation on the TiO2 surface. Therefore, we studied the reaction mechanisms and their corresponding rates as a function of the temperature for the dehydrogenation of the species on the surface. We found that the stabilities of C and CH are significantly lower than those of CH3 and CH2. The hydrogenation rates of the different species are significantly higher than the dehydrogenation rates in a temperature range of 300−1000 K. Furthermore, we found that dehydrogenation of CH3, CH2, and CH will only occur at appreciable rates starting from 600, 900, and 900 K, respectively. On the basis of these results, it is clear that the anatase (001) surface has a high coke resistance, and it is thus not likely that the surface will become poisoned by coke during dry reforming of methane. As the rate limiting step in dry reforming is the dissociative adsorption of CH4, we studied an alternative approach to thermal catalysis. We found that the temperature threshold for dry reforming is at least 700 K. This threshold temperature may be lowered by the use of plasma-catalysis, where the appreciable rates of adsorption of plasma-generated CHx radicals result in bypassing the rate limiting step of the reaction. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000431723700014 | Publication Date | 2018-05-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 1 | Open Access | OpenAccess |
| Notes | Federaal Wetenschapsbeleid, IAP/7 ; Fonds Wetenschappelijk Onderzoek, G.0217.14N ; Onderzoeksfonds, Universiteit Antwerpen, 32249 ; | Approved | Most recent IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:151529c:irua:152816 | Serial | 5000 | ||
| Permanent link to this record | |||||
| Author | Vermeiren, V.; Bogaerts, A. | ||||
| Title | Supersonic Microwave Plasma: Potential and Limitations for Energy-Efficient CO2Conversion | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 122 | Issue | 45 | Pages | 25869-25881 |
| Keywords |
A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | Supersonic flows provide a high thermodynamic nonequilibrium, which is crucial for energy-efficient conversion of CO 2 in microwave plasmas and are therefore of great interest. However, the effect of the flow on the chemical reactions is poorly understood. In this work, we present a combined flow and plasma chemical kinetics model of a microwave CO 2 plasma in a Laval nozzle setup. The effects of the flow field on the different dissociation and recombination mechanisms, the vibrational distribution, and the vibrational transfer mechanism are discussed. In addition, the effect of experimental parameters, like position of power deposition, outlet pressure, and specific energy input, on the CO 2 conversion and energy efficiency is examined. The short residence time of the gas in the plasma region, the shockwave, and the maximum critical heat, and thus power, that can be added to the flow to avoid thermal choking are the main obstacles to reaching high energy efficiencies. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000451101400016 | Publication Date | 2018-11-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 5 | Open Access | Not_Open_Access |
| Notes | Fonds Wetenschappelijk Onderzoek, G.0383.16N ; | Approved | Most recent IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:155412 | Serial | 5070 | ||
| Permanent link to this record | |||||