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Author |
Baskurt, M.; Eren, I.; Yagmurcukardes, M.; Sahin, H. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Vanadium dopant- and strain-dependent magnetic properties of single-layer VI₃ |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Applied Surface Science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
508 |
Issue |
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Pages |
144937-6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Motivated by the recent synthesis of two-dimensional VI3 [Kong et al. Adv. Mater. 31, 1808074 (2019)], we investigate the effect of V doping on the magnetic and electronic properties of monolayer VI3 by means of first-principles calculations. The dynamically stable semiconducting ferromagnetic (FM) and antiferromagnetic (AFM) phases of monolayer VI3 are found to display distinctive vibrational features that the magnetic state can be distinguished by Raman spectroscopy. In order to clarify the effect of experimentally observed excessive V atoms, the magnetic and electronic properties of the V-doped VI3 structures are analyzed. Our findings indicate that partially doped VI3 structures display FM ground state while the fully-doped structure exhibits AFM ground state. The fully-doped monolayer VI3 is found to be a semiconductor with a relatively larger band gap than its pristine structure. In addition, strain-dependent electronic and magnetic properties of fully- and partially-doped VI3 structures reveal that pristine monolayer displays a FM-to-AFM phase transition with robust semiconducting nature for 5% of compressive strain, while fully-doped monolayer VI3 structure possesses AFM-to-FM semiconducting transition at tensile strains larger than 4%. In contrast, the partially-doped VI3 monolayers are found to display robust FM ground state under biaxial strain. Its dopant and strain tunable electronic and magnetic nature makes monolayer VI3 a promising material for applications in nanoscale spintronic devices. |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000516818700040 |
Publication Date |
2019-12-24 |
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Series Volume |
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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 |
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Impact Factor |
6.7 |
Times cited |
10 |
Open Access |
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Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. Acknowledges financial support from the TUBITAK under the project number 117F095. H.S. acknowledges support from Turkish Academy of Sciences under the GEBIP program. This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; |
Approved |
Most recent IF: 6.7; 2020 IF: 3.387 |
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Call Number |
UA @ admin @ c:irua:168595 |
Serial |
6652 |
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Permanent link to this record |
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Author |
Bafekry, A.; Akgenc, B.; Shayesteh, S.F.; Mortazavi, B. |
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Title |
Tunable electronic and magnetic properties of graphene/carbon-nitride van der Waals heterostructures |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Applied Surface Science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
505 |
Issue |
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Pages |
144450-144459 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this paper, we explore the electronic properties of C3N, C3N4 and C4N3 and graphene (Gr) van der Waals heterostructures by conducing extensive first-principles calculations. The acquired results show that these heterostructures can show diverse electronic properties, such as the metal (Gr on C3N), semiconductor with narrow band gap (Gr on C3N4) and ferromagnetic-metal (Gr on C4N3). We furthermore explored the effect of vacancies, atom substitution, topological, antisite and Stone-Wales defects on the structural and electronic properties of considered heterostructures. Our results show that the vacancy defects introduce localized states near the Fermi level and create a local magnetic moment. The Gr/C3N heterostructures with the single and double vacancy defects exhibit a ferromagnetic-metal, while Stone-Wales defects show an indirect semiconductor with the band gap of 0.2 eV. The effects of adsorption and insertion of O, C, Be, Cr, Fe and Co atoms on the electronic properties of Gr/C3N have been also elaborately studied. Our results highlight that the electronic and magnetic properties of garphene/carbon-nitride lateral heterostructures can be effectively modified by point defects and impurities. |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000510846500052 |
Publication Date |
2019-11-18 |
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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 |
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Impact Factor |
6.7 |
Times cited |
26 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 6.7; 2020 IF: 3.387 |
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Call Number |
UA @ admin @ c:irua:167732 |
Serial |
6638 |
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Permanent link to this record |
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Author |
Sozen, Y.; Eren, I.; Ozen, S.; Yagmurcukardes, M.; Sahin, H. |
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Title |
Interaction of Ge with single layer GaAs : from Ge-island nucleation to formation of novel stable monolayers |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Applied Surface Science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
505 |
Issue |
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Pages |
144218-7 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this study, reactivity of single-layer GaAs against Ge atoms is studied by means of ab initio density functional theory calculations. Firstly, it is shown that Ge atoms interact quite strongly with the GaAs layer which allows the formation of Ge islands while it hinders the growth of detached germanene monolayers. It is also predicted that adsorption of Ge atoms on GaAs single-layer lead to formation of two novel stable single-layer crystal structures, namely 1H-GaGeAs and 1H(A)-GaGeAs. Both the total energy optimizations and the calculated vibrational spectra indicate the dynamical stability of both single layer structures. Moreover, although both structures crystallize in 1H phase, 1H-GaGeAs and 1H(A)-GaGeAs exhibit distinctive vibrational features in their Raman spectra which is quite important for distinguishing the structures. In contrast to the semiconducting nature of single-layer GaAs, both polytypes of GaGeAs exhibit metallic behavior confirmed by the electronic band dispersions. Furthermore, the linear-elastic constants, in-plane stiffness and Poisson ratio, reveal the ultrasoft nature of the GaAs and GaGeAs structures and the rigidity of GaAs is found to be slightly enhanced via Ge adsorption. With their stable, ultra-thin and metallic properties, predicted single-layer GaGeAs structures can be promising candidates for nanoscale electronic and mechanical applications. |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000510846500026 |
Publication Date |
2019-11-02 |
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ISSN |
0169-4332 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
6.7 |
Times cited |
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Open Access |
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Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid eInfrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under the project number 117F095. H.S. acknowledges support from Turkish Academy of Sciences under the GEBIP program. This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; |
Approved |
Most recent IF: 6.7; 2020 IF: 3.387 |
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Call Number |
UA @ admin @ c:irua:167733 |
Serial |
6548 |
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Permanent link to this record |
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Author |
Nematollahi, P.; Neyts, E.C. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Direct methane conversion to methanol on M and MN4 embedded graphene (M = Ni and Si): a comparative DFT study |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
496 |
Issue |
496 |
Pages |
143618 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The ever increasing global production and dispersion of methane requires novel chemistry to transform it into easily condensable energy carriers that can be integrated into the chemical infrastructure. In this context, single atom catalysts have attracted considerable interest due to their outstanding catalytic activity. We here use density functional theory (DFT) computations to compare the reaction and activation energies of M and MN4 embedded graphene (M = Ni and Si) on the methane-to-methanol conversion near room temperature. Thermodynamically, conversion of methane to methanol is energetically favorable at ambient conditions. Both singlet and triplet spin state of the studied systems are considered in all of the calculations. The DFT results show that the barriers are significantly lower when the complexes are in the triplet state than in the singlet state. In particular, Si-G with the preferred spin multiplicity of triplet seems to be viable catalysts for methane oxidation thanks to the corresponding lower energy barriers and higher stability of the obtained configurations. Our results provide insights into the nature of methane conversion and may serve as guidance for fabricating cost-effective graphene-based single atom catalysts. |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000488957400004 |
Publication Date |
2019-08-12 |
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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 |
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Impact Factor |
3.387 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.387 |
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Call Number |
UA @ admin @ c:irua:163695 |
Serial |
6294 |
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Permanent link to this record |
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Author |
Sathiyamoorthy, S.; Girijakumari, G.; Kannan, P.; Venugopal, K.; Thiruvottriyur Shanmugam, S.; Veluswamy, P.; De Wael, K.; Ikeda, H. |
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Title |
Tailoring the functional properties of polyurethane foam with dispersions of carbon nanofiber for power generator applications |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
449 |
Issue |
449 |
Pages |
507-513 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
To produce effective thermoelectric nanocomposites, carbon nanofibers (CNF) incorporated polyurethane (PU) foams with nanocomposites are prepared via in-situ polymerization method to create a synergy that would produce a high thermopower. The formation mechanism of foams, the reaction kinetics, and the physical properties such as density and water absorption studied before and after CNF incorporation. The microscopy images showed a uniform dispersion of CNF in the PU matrix of the prepared foams. Spectroscopic studies such as X-ray photoelectron and laser Raman spectroscopy suggested the existence of a tight intermolecular binding interaction between the carbon nanofibers and the PU matrix in the prepared composite foams. It found that the thermopower is directly dependent on the concentration of carbon nanofiber since, with rising concentration of 1%3%, the coefficient values increased from 1.2 μV/K to 11.9 μV/K respectively, a value higher than that of earlier report. This unique nanocomposite offers a new opportunity to recycle waste heat in portable/wearable electronics and other applications, which will broaden the development of low weight and mechanical flexibility. |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000438025400064 |
Publication Date |
2018-02-06 |
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ISSN |
0169-4332 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.387 |
Times cited |
4 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.387 |
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Call Number |
UA @ admin @ c:irua:151287 |
Serial |
5868 |
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Permanent link to this record |
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Author |
Nematollahi, P.; Esrafili, M.D.; Neyts, E.C. |
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Title |
The role of healed N-vacancy defective BC2N sheet and nanotube by NO molecule in oxidation of NO and CO gas molecules |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Surface science : a journal devoted to the physics and chemistry of interfaces |
Abbreviated Journal |
Surf Sci |
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Volume |
672-673 |
Issue |
672-673 |
Pages |
39-46 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this study, the healing of N-vacancy boron carbonitride nanosheet (NV-BC2NNS) and nanotube (NV-BC2NNT) by NO molecule is studied by means of density functional theory calculations. Two different N-vacancies are considered in each of these structures in which the vacancy site is surrounded by either three B-atoms (NB) or by two B- and one C-atom (NBC). By means of the healed BC2NNS and BC2NNT as a support, the removal of two toxic gas molecules (NO and CO) are applicable. It should be noted that the obtained energy barriers of both healing and oxidizing processes are significantly lower than those of graphene, carbon nanotubes or boron nitride nanostructures. Also, at the end of the oxidation process, the pure BC2NNS or BC2NNT is obtained without any additional defects. Therefore, by using this method, we can considerably purify the defective BC2NNS/BC2NNT. Moreover, according to the thermochemistry calculations we can further confirm that the healing process of the NV-BC2NNS and NV-BC2NNT by NO are feasible at room temperature. So, we can claim that this study could be very helpful in both purifying the defective BC2NNS/BC2NNT while in the same effort removing toxic NO and CO gases. |
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Place of Publication |
Amsterdam |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000432614700007 |
Publication Date |
2018-03-08 |
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Edition |
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ISSN |
0039-6028 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.062 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 2.062 |
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Call Number |
UA @ lucian @ c:irua:151478 |
Serial |
5044 |
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Permanent link to this record |
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Author |
Nematollahi, P.; Neyts, E.C. |
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Title |
A comparative DFT study on CO oxidation reaction over Si-doped BC2N nanosheet and nanotube |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
439 |
Issue |
439 |
Pages |
934-945 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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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. |
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Place of Publication |
Amsterdam |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000427457100112 |
Publication Date |
2018-01-08 |
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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 |
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Impact Factor |
3.387 |
Times cited |
8 |
Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 3.387 |
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Call Number |
UA @ lucian @ c:irua:150745 |
Serial |
4960 |
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Permanent link to this record |
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Author |
Aydin, H.; Bacaksiz, C.; Yagmurcukardes, N.; Karakaya, C.; Mermer, O.; Can, M.; Senger, R.T.; Sahin, H.; Selamet, Y. |
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Title |
Experimental and computational investigation of graphene/SAMs/n-Si Schottky diodes |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Applied Surface Science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
428 |
Issue |
428 |
Pages |
1010-1017 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We have investigated the effect of two different self-assembled monolayers (SAMs) on electrical characteristics of bilayer graphene (BLG)/n-Si Schottky diodes. Novel 4“bis(diphenylamino)-1, 1':3”-terpheny1-5' carboxylic acids (TPA) and 4,4-di-9H-carbazol-9-y1-1,1':3'1'-terpheny1-5' carboxylic acid (CAR) aromatic SAMs have been used to modify n-Si surfaces. Cyclic voltammetry (CV) and Kelvin probe force microscopy (KPFM) results have been evaluated to verify the modification of n-Si surface. The current-voltage (I-V) characteristics of bare and SAMs modified devices show rectification behaviour verifying a Schottky junction at the interface. The ideality factors (n) from ln(I)-V dependences were determined as 2.13,1.96 and 2.07 for BLG/n-Si, BLG/TPA/n-Si and BLG/CAR/n-Si Schottky diodes, respectively. In addition, Schottky barrier height (SBH) and series resistance (Rs) of SAMs modified diodes were decreased compared to bare diode due to the formation of a compatible interface between graphene and Si as well as n-n interaction between aromatic SAMs and graphene. The CAR-based device exhibits better diode characteristic compared to the TPA-based device. Computational simulations show that the BLG/CAR system exhibits smaller energy-level-differences than the BLG/TPA, which supports the experimental findings of a lower Schottky barrier and series resistance in BLG/CAR diode. (C) 2017 Elsevier B.V. All rights reserved. |
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Place of Publication |
Amsterdam |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000415227000128 |
Publication Date |
2017-09-29 |
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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 |
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Impact Factor |
3.387 |
Times cited |
2 |
Open Access |
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Notes |
; This work was supported by TUBITAK (The Scientific and Technical Research Council of Turkey) with project number 112T946. We also thank AQuReC (Applied Quantum Research Center) for Raman measurements. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Bilim Akademisi The Science Academy, Turkey under the BAGEP program. ; |
Approved |
Most recent IF: 3.387 |
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Call Number |
UA @ lucian @ c:irua:154608UA @ admin @ c:irua:154608 |
Serial |
5101 |
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Permanent link to this record |
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Author |
Scalise, E.; Cinquanta, E.; Houssa, M.; van den Broek, B.; Chiappe, D.; Grazianetti, C.; Pourtois, G.; Ealet, B.; Molle, A.; Fanciulli, M.; Afanas’ev, V.V.; Stesmans, A.; |
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Title |
Vibrational properties of epitaxial silicene layers on (111) Ag |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
291 |
Issue |
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Pages |
113-117 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The electronic and vibrational properties of three different reconstructions of silicene on Ag(1 1 1) are calculated and compared to experimental results. The 2D epitaxial silicon layers, namely the (4 x 4), (root 13 x root 13) and (2 root 3 x 2 root 3) phases, exhibit different electronic and vibrational properties. Few peaks in the experimental Raman spectrum are identified and attributed to the vibrational modes of the silicene layers. The position and behavior of the Raman peaks with respect to the excitation energy are shown to be a fundamental tool to investigate and discern different phases of silicene on Ag( 1 1 1). (C) 2013 Elsevier B.V. All rights reserved. |
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Place of Publication |
Amsterdam |
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Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000329327700025 |
Publication Date |
2013-09-01 |
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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 |
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Impact Factor |
3.387 |
Times cited |
36 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.387; 2014 IF: 2.711 |
|
|
Call Number |
UA @ lucian @ c:irua:113767 |
Serial |
3843 |
|
Permanent link to this record |
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Author |
van den Broek, B.; Houssa, M.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
First-principles electronic functionalization of silicene and germanene by adatom chemisorption |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
|
|
Volume |
291 |
Issue |
|
Pages |
104-108 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
This study presents first-principles results on the electronic functionalization of silicene and germanene monolayers by means of chemisorption of adatom species H, Li, F, Sc, Ti, V. Three general adatom-monolayer configurations are considered, each having its distinct effect on the electronic structure, yielding metallic or semiconducting dispersions depending on the adatom species and configuration. The induced bandgap is a (in)direct F gap ranging from 0.2 to 2.3 eV for both silicene and germanene. In general the alternating configuration was found to be the most energetically stable. The boatlike and chairlike conformers are degenerate with the former having anisotropic effective carrier masses. The top configuration leads to the planar monolayer and predominately to a gapped dispersion. The hollow configuration with V adatoms retains the Dirac cone, but with strong orbital planar hybridization at the Fermi level. We also observe a planar surface state the Fermi level for the latter systems. (C) 2013 Elsevier B.V. All rights reserved. |
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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 ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000329327700023 |
Publication Date |
2013-09-17 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
32 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2014 IF: 2.711 |
|
|
Call Number |
UA @ lucian @ c:irua:113766 |
Serial |
1208 |
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Permanent link to this record |
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Author |
Houssa, M.; van den Broek, B.; Scalise, E.; Ealet, B.; Pourtois, G.; Chiappe, D.; Cinquanta, E.; Grazianetti, C.; Fanciulli, M.; Molle, A.; Afanas’ev, V.V.; Stesmans, A.; |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Theoretical aspects of graphene-like group IV semiconductors |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
|
|
Volume |
291 |
Issue |
|
Pages |
98-103 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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|
Abstract |
Silicene and germanene are the silicon and germanium counterparts of graphene, respectively. Recent experimental works have reported the growth of silicene on (1 1 1)Ag surfaces with different atomic configurations, depending on the growth temperature and surface coverage. We first theoretically study the structural and electronic properties of silicene on (1 1 1) Ag surfaces, focusing on the (4 x 4) silicene/Ag structure. Due to symmetry breaking in the silicene layer (nonequivalent number of top and bottom Si atoms), the corrugated silicene layer, with the Ag substrate removed, is predicted to be semiconducting, with a computed energy bandgap of about 0.3 eV. However, the hybridization between the Si 3p orbitals and the Ag 5s orbital in the silicene/(1 1 1)Ag slab model leads to an overall metallic system, with a distribution of local electronic density of states, which is related to the slightly disordered structure of the silicene layer on the (1 1 1)Ag surface. We next study the interaction of silicene and germanene with different hexagonal non-metallic substrates, namely ZnS and ZnSe. On reconstructed (0 0 0 1)ZnS or ZnSe surfaces, which should be more energetically stable for very thin layers, silicene and germanene are found to be semiconducting. Remarkably, the nature and magnitude of their energy bandgap can be controlled by an out-of-plane electric field, an important finding for the potential use of these materials in nanoelectronic devices. (C) 2013 Elsevier B. V. All rights reserved. |
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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 ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000329327700022 |
Publication Date |
2013-09-18 |
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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 |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
20 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2014 IF: 2.711 |
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|
Call Number |
UA @ lucian @ c:irua:113765 |
Serial |
3603 |
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Permanent link to this record |
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Author |
Bittencourt, C.; Felten, A.; Douhard, B.; Colomer, J.-F.; Van Tendeloo, G.; Drube, W.; Ghijsen, J.; Pireaux, J.-J. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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|
Title |
Metallic nanoparticles on plasma treated carbon nanotubes : $Nano2hybrids$ |
Type |
A1 Journal article |
|
Year |
2007 |
Publication |
Surface science : a journal devoted to the physics and chemistry of interfaces
T2 – International Conference on NANO-Structures Self Assembling, JUL 02-06, 2006, Aix en Provence, FRANCE |
Abbreviated Journal |
Surf Sci |
|
|
Volume |
601 |
Issue |
13 |
Pages |
2800-2804 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Multi-wall carbon nanotubes (MWCNTs) were decorated with metal clusters by thermal evaporation. Transmission electron microscopy (TEM) shows that the nature and extent of metal coverage can be varied by plasma treating the MWCNT surface. The metal clusters on oxygen plasma treated arc-discharge MWCNTs have a more dense distribution than the clusters evaporated on as-synthesized are-discharge MWCNTs. In contrast, the plasma treatment did not affect the cluster distribution on CVD MWCNTs. Analyses of the valence band and the core levels by X-ray photoelectron spectroscopy suggest poor charge transfer between gold clusters and MWCNTs; on the contrary suggest good charge transfer between Ni clusters and MWCNTs. (c) 2007 Elsevier B. V. All rights reserved. |
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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 ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000248030100055 |
Publication Date |
2006-12-21 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0039-6028; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.062 |
Times cited |
44 |
Open Access |
|
|
|
Notes |
Pai-V 1 |
Approved |
Most recent IF: 2.062; 2007 IF: 1.855 |
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|
Call Number |
UA @ lucian @ c:irua:102663 |
Serial |
2011 |
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Permanent link to this record |
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Author |
Aichele, T.; Robin, I.-C.; Bougerol, C.; André, R.; Tatarenko, S.; Van Tendeloo, G. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
CdSe quantum dot formation induced by amorphous Se |
Type |
A1 Journal article |
|
Year |
2007 |
Publication |
Surface science : a journal devoted to the physics and chemistry of interfaces
T2 – International Conference on NANO-Structures Self Assembling, JUL 02-06, 2006, Aix en Provence, FRANCE |
Abbreviated Journal |
Surf Sci |
|
|
Volume |
601 |
Issue |
13 |
Pages |
2664-2666 |
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|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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|
Abstract |
The mechanism allowing the transition from a two-dimensional strained layer of CdSe on ZnSe to self-assembled islands induced by the use of amorphous selenium is still not fully understood. For a better understanding, atomic force microscopy and transmission electron microscopy studies were performed on CdSe films with a thickness close to that for quantum dot formation. Below this thickness, the sample surface results in undulations along the [110] crystal direction, while few quantum dots are situated in the wave valleys. Plan view transmission electron microscopy studies reveal a strong anisotropy of the islands and show that the Se desorption conditions are crucial. (C) 2006 Elsevier B.V. All rights reserved. |
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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 |
|
Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000248030100027 |
Publication Date |
2006-12-22 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0039-6028; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
2.062 |
Times cited |
|
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.062; 2007 IF: 1.855 |
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|
Call Number |
UA @ lucian @ c:irua:102668 |
Serial |
304 |
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Permanent link to this record |
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Author |
de Mondt, R.; Adriaensen, L.; Vangaever, F.; Lenaerts, J.; van Vaeck, L.; Gijbels, R. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Empirical evaluation of metal deposition for the analysis of organic compounds with static secondary ion mass spectrometry (S-SIMS) |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
|
|
Volume |
252 |
Issue |
19 |
Pages |
6652-6655 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
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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 |
|
Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000240609900063 |
Publication Date |
2006-05-05 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
9 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2006 IF: 1.436 |
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|
Call Number |
UA @ lucian @ c:irua:58812 |
Serial |
1034 |
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Permanent link to this record |
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Author |
Adriaensen, L.; Vangaever, F.; Lenaerts, J.; Gijbels, R. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
S-SIMS and MetA-SIMS study of organic additives in thin polymer coatings |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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|
Volume |
252 |
Issue |
19 |
Pages |
6628-6631 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
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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 ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000240609900057 |
Publication Date |
2006-06-20 |
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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 |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
3 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2006 IF: 1.436 |
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|
Call Number |
UA @ lucian @ c:irua:60083 |
Serial |
2937 |
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Permanent link to this record |
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Author |
Ignatova, V.A.; Conard, T.; Möller, W.; Vandervorst, W.; Gijbels, R. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Depth profiling of ZrO2/SiO2/Si stacks : a TOF-SIMS and computer simulation study |
Type |
A1 Journal article |
|
Year |
2004 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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|
Volume |
231/232 |
Issue |
|
Pages |
603-608 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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|
Abstract |
This study is dedicated to a better understanding of the processes occurring under ion bombardment of ultra-thin ZrO2/SiO2/Si gate dielectric stacks. Complex-shaped depth profiles were obtained by using TOF-SIMS with dual beam (500 eV for sputtering and 10 keV for analysis) Ar+ ions. The SIMS intensities of all the elements depend critically on the amount of oxygen at any moment of the sputtering process. Increased intensity is observed at the surface and at the ZrO2/SiO2 interface. A long tail of the Zr signal is present in the Si substrate, even after the second (SiO2/Si) interface, and a double bump structure in the Zr-90 and ZrO dimer is observed, which is more pronounced with increasing thickness of the interfacial SiO2 layer. Computer simulations using the dynamic Monte Carlo code (TRIDYN) are performed in order to distinguish the ion bombardment-induced effects from changes in the ionization degree. The original code is extended with simple models for the ionization mechanism and for the molecular yield during sputtering. Oxygen preferential sputtering at the surface and ballistic transport of Zr towards and through the interface are clearly demonstrated, but there is also evidence that due to recoil implantation oxygen gets piled-up near the ZrO2/SiO2 interface. (C) 2004 Elsevier B.V. All rights reserved. |
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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 ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000222427700118 |
Publication Date |
2004-05-30 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
4 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2004 IF: 1.497 |
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|
Call Number |
UA @ lucian @ c:irua:51976 |
Serial |
651 |
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Permanent link to this record |
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|
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Author |
Adriaensen, L.; Vangaever, F.; Gijbels, R. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
A comparative study of carbocyanine dyes measured with TOF-SIMS and other mass spectrometric techniques |
Type |
A1 Journal article |
|
Year |
2004 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
231/232 |
Issue |
|
Pages |
348-352 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
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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 |
|
Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000222427700067 |
Publication Date |
2004-04-29 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2004 IF: 1.497 |
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|
Call Number |
UA @ lucian @ c:irua:46802 |
Serial |
420 |
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Permanent link to this record |
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Author |
Adriaensen, L.; Vangaever, F.; Gijbels, R. |
![find record details (via OpenURL) openurl](img/xref.gif)
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|
Title |
Organic SIMS: the influence of time on the ion yield enhancement by silver and gold deposition |
Type |
A1 Journal article |
|
Year |
2004 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
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|
Volume |
231/232 |
Issue |
|
Pages |
256-260 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
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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 ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000222427700049 |
Publication Date |
2004-04-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
10 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2004 IF: 1.497 |
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|
Call Number |
UA @ lucian @ c:irua:46804 |
Serial |
2510 |
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Permanent link to this record |
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Author |
Lenaerts, J.; Gijbels, R.; van Vaeck, L.; Verlinden, G.; Geuens, I. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Imaging TOF-SIMS for the surface analysis of silver halide microcrystals |
Type |
A1 Journal article |
|
Year |
2003 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
|
|
Volume |
203/204 |
Issue |
|
Pages |
614-619 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
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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 |
|
Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000180527300138 |
Publication Date |
2002-12-30 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2003 IF: 1.284 |
|
|
Call Number |
UA @ lucian @ c:irua:51974 |
Serial |
1556 |
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Permanent link to this record |
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Author |
de Witte, H.; Conard, T.; Vandervorst, W.; Gijbels, R. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Ion-bombardment artifact in TOF-SIMS analysis of ZrO2/SiO2/Si stacks |
Type |
A1 Journal article |
|
Year |
2003 |
Publication |
Applied surface science |
Abbreviated Journal |
Appl Surf Sci |
|
|
Volume |
203 |
Issue |
|
Pages |
523-526 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
We analyzed ultra-thin ZrO2/SiO2/Si gate dielectrics under post-deposition anneals in dry O-2 at temperatures from 500 to 700 degreesC. TOF-SIMS profiling of ZrO2/SiO2/Si stacks is hampered by many sputter induced artifacts. The depletion of oxygen leads to a decrease in SIMS intensities. However, preferential sputtering is accompanied by transport of the depleted species towards the surface. Due to recoil implantation oxygen gets piled-up near the ZrO2/SiO2 interface. Either normal or radiation-enhanced diffusion transports oxygen back to the surface. Simultaneously also segregation of zirconium towards and through the interface is observed, resulting in a large zirconium tail in the underlying silicon substrate. (C) 2002 Elsevier Science B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Elsevier science bv |
Place of Publication |
Amsterdam |
Editor |
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Language |
|
Wos ![sorted by Wos field, descending order (down)](img/sort_desc.gif) |
000180527300119 |
Publication Date |
2002-12-30 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0169-4332; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.387 |
Times cited |
15 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.387; 2003 IF: 1.284 |
|
|
Call Number |
UA @ lucian @ c:irua:51975 |
Serial |
1743 |
|
Permanent link to this record |