| Records |
| Author |
Shirazi, M.; Bogaerts, A.; Neyts, E.C. |
Title  |
A DFT study of H-dissolution into the bulk of a crystalline Ni(111) surface: a chemical identifier for the reaction kinetics |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
19 |
Issue |
19 |
Pages |
19150-19158 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
In this study, we investigated the diffusion of H-atoms to the subsurface and their further diffusion into the bulk of a Ni(111) crystal by means of density functional theory calculations in the context of thermal and plasma-assisted catalysis. The H-atoms at the surface can originate from the dissociative adsorption of H2 or CH4 molecules, determining the surface H-coverage. When a threshold H-coverage is passed, corresponding to 1.00 ML for the crystalline Ni(111) surface, the surface-bound H-atoms start to diffuse to the subsurface. A similar threshold coverage is observed for the interstitial H-coverage. Once the interstitial sites are filled up with a coverage above 1.00 ML of H, dissolution of interstitial H-atoms to the layer below the interstitial sites will be initiated. Hence, by applying a high pressure or inducing a reactive plasma and high temperature, increasing the H-flux to the surface, a large amount of hydrogen can diffuse in a crystalline metal like Ni and can be absorbed. The formation of metal hydride may modify the entire reaction kinetics of the system. Equivalently, the H-atoms in the bulk can easily go back to the surface and release a large amount of heat. In a plasma process, H-atoms are formed in the plasma, and therefore the energy barrier for dissociative adsorption is dismissed, thus allowing achievement of the threshold coverage without applying a high pressure as in a thermal process. As a result, depending on the crystal plane and type of metal, a large number of H-atoms can be dissolved (absorbed) in the metal catalyst, explaining the high efficiency of plasma-assisted catalytic reactions. Here, the mechanism of H-dissolution is established as a chemical identifier for the investigation of the reaction kinetics of a chemical process. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000406334300034 |
Publication Date |
2017-06-22 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.123 |
Times cited |
10 |
Open Access |
OpenAccess |
| Notes |
Financial support from the Reactive Atmospheric Plasma processIng – eDucation (RAPID) network, through the EU 7th Framework Programme (grant agreement no. 606889), is gratefully acknowledged. The calculations were performed 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 Universiteit Antwerpen. |
Approved |
Most recent IF: 4.123 |
| Call Number |
PLASMANT @ plasmant @ c:irua:144794 |
Serial |
4633 |
| Permanent link to this record |
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| Author |
Hoon Park, J.; Kumar, N.; Hoon Park, D.; Yusupov, M.; Neyts, E.C.; Verlackt, C.C.W.; Bogaerts, A.; Ho Kang, M.; Sup Uhm, H.; Ha Choi, E.; Attri, P.; |
| Title |
A comparative study for the inactivation of multidrug resistance bacteria using dielectric barrier discharge and nano-second pulsed plasma |
Type |
A1 Journal article |
| Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
5 |
Issue |
5 |
Pages |
13849 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Bacteria can be inactivated through various physical and chemical means, and these have always been the focus of extensive research. To further improve the methodology for these ends, two types of plasma systems were investigated: nano-second pulsed plasma (NPP) as liquid discharge plasma and an Argon gas-feeding dielectric barrier discharge (Ar-DBD) as a form of surface plasma. To understand the sterilizing action of these two different plasma sources, we performed experiments with Staphylococcus aureus (S. aureus) bacteria (wild type) and multidrug resistant bacteria (Penicillum-resistant, Methicillin-resistant and Gentamicin-resistant). We observed that both plasma sources can inactivate both the wild type and multidrug-resistant bacteria to a good extent. Moreover, we observed a change in the surface morphology, gene expression and β-lactamase activity. Furthermore, we used X-ray photoelectron spectroscopy to investigate the variation in functional groups (C-H/C-C, C-OH and C=O) of the peptidoglycan (PG) resulting from exposure to plasma species. To obtain atomic scale insight in the plasma-cell interactions and support our experimental observations, we have performed molecular dynamics simulations to study the effects of plasma species, such as OH, H2O2, O, O3, as well as O2 and H2O, on the dissociation/formation of above mentioned functional groups in PG. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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| Language |
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Wos |
000360909000001 |
Publication Date |
2015-09-09 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2045-2322; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.259 |
Times cited |
32 |
Open Access |
|
| Notes |
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Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
| Call Number |
c:irua:127410 |
Serial |
419 |
| Permanent link to this record |
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| Author |
Nematollahi, P.; Neyts, E.C. |
| Title |
A comparative DFT study on CO oxidation reaction over Si-doped BC2N nanosheet and nanotube |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
| Volume |
439 |
Issue |
439 |
Pages |
934-945 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
In this study, we performed density functional theory (DFT) calculations to investigate different reaction mechanisms of CO oxidation catalyzed by the Si atom embedded defective BC2N nanostructures as well as the analysis of the structural and electronic properties. The structures of all the complexes are optimized and characterized by frequency calculations at the M062X/6-31G* computational level. Also, The electronic structures and thermodynamic parameters of adsorbed CO and O-2 molecules over Si-doped BC2N nanostructures are examined in detail. Moreover, to investigate the curvature effect on the CO oxidation reaction, all the adsorption and CO oxidation reactions on a finite-sized armchair (6,6) Si-BC2NNT are also studied. Our results indicate that there can be two possible pathways for the CO oxidation with O-2 molecule: O-2(g) + CO(g) -> O-2(ads) + CO(ads) -> CO2(g) + O-(ads) and O-(ads) + CO(g) -> CO2(g). The first reaction proceeds via the Langmuir-Hinshelwood (LH) mechanism while the second goes through the Eley-Rideal (ER) mechanism. On the other hand, by increasing the tube diameter, the energy barrier increases due to the strong adsorption energy of the O-2 molecule which is related to its dissociation over the tube surface. Our calculations indicate that the two step energy barrier of the oxidation reaction over Si-BC2NNS is less than that over the Si-BC2NNT. Hence, Si-BC2NNS may serve as an efficient and highly activated substrate to CO oxidation rather than (4,4) Si-BC2NNT. (C) 2018 Elsevier B.V. All rights reserved. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Amsterdam |
Editor |
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| Language |
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Wos |
000427457100112 |
Publication Date |
2018-01-08 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0169-4332 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.387 |
Times cited |
8 |
Open Access |
Not_Open_Access |
| Notes |
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Approved |
Most recent IF: 3.387 |
| Call Number |
UA @ lucian @ c:irua:150745 |
Serial |
4960 |
| Permanent link to this record |
