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| Author | Kandemir, A.; Peeters, F.M.; Sahin, H. | ||||
| Title | Monitoring the effect of asymmetrical vertical strain on Janus single layers of MoSSe via spectrum | Type | A1 Journal article | ||
| Year | 2018 | Publication | The journal of chemical physics | Abbreviated Journal | J Chem Phys |
| Volume | 149 | Issue | 8 | Pages | 084707 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Using first principles calculations, we study the structural and phononic properties of the recently synthesized Janus type single layers of molybdenum dichalcogenides. The Janus MoSSe single layer possesses 2H crystal structure with two different chalcogenide sides that lead to out-of-plane anisotropy. By virtue of the asymmetric structure of the ultra-thin Janus type crystal, we induced the out-of-plane anisotropy to show the distinctive vertical pressure effect on the vibrational properties of the Janus material. It is proposed that for the corresponding Raman active optical mode of the Janus structure, the phase modulation and the magnitude ratio of the strained atom and its first neighbor atom adjust the distinctive change in the eigen-frequencies and Raman activity. Moreover, a strong variation in the Raman activity of the Janus structure is obtained under bivertical and univertical strains. Not only eigen-frequency shifts but also Raman activities of the optical modes of the Janus structure exhibit distinguishable features. This study reveals that the vertical anisotropic feature of the Janus structure under Raman measurement allows us to distinguish which side of the Janus crystal interacts with the externals (substrate, functional adlayers, or dopants). Published by AIP Publishing. | ||||
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| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos  |
000444035800044 | Publication Date | 2018-08-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-9606 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.965 | Times cited | 11 | Open Access | |
| Notes | ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from TUBITAK under Project No. 117F095. F.M.P. was supported by the FLAG-ERA-TRANS<INF>2D</INF>TMD. ; | Approved | Most recent IF: 2.965 | ||
| Call Number | UA @ lucian @ c:irua:153711UA @ admin @ c:irua:153711 | Serial | 5115 | ||
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| Author | Verlackt, C.C.W.; Van Boxem, W.; Bogaerts, A. | ||||
| Title | Transport and accumulation of plasma generated species in aqueous solution | Type | A1 Journal article | ||
| Year | 2018 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 20 | Issue | 10 | Pages | 6845-6859 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | The interaction between cold atmospheric pressure plasma and liquids is receiving increasing attention for various applications. In particular, the use of plasma-treated liquids (PTL) for biomedical applications is of growing importance, in particular for sterilization and cancer treatment. However, insight into the underlying mechanisms of plasma–liquid interactions is still scarce. Here, we present a 2D fluid dynamics model for the interaction between a plasma jet and liquid water. Our results indicate that the formed reactive species originate from either the gas phase (with further solvation) or are formed at the liquid interface. A clear increase in the aqueous density of H2O2, HNO2/NO2- and NO3- is observed as a function of time, while the densities of O3, HO2/O2- and ONOOH/ONOO- are found to quickly reach a maximum due to chemical reactions in solution. The trends observed in our model correlate well with experimental observations from the literature. |
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| Language | Wos |
000429286100009 | Publication Date | 2018-02-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 35 | Open Access | OpenAccess |
| Notes | The authors thank Petr Luke`s (Institute of Plasma Physics AS CR, Czech Republic) and Yury Gorbanev (UAntwerp, group PLASMANT) for the fruitful discussions regarding the chemistry in the model and the plasma–liquid interactions. | Approved | Most recent IF: 4.123 | ||
| Call Number | PLASMANT @ plasmant @c:irua:149557 | Serial | 4908 | ||
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| Author | Bal, K.M.; Neyts, E.C. | ||||
| Title | Modelling molecular adsorption on charged or polarized surfaces: a critical flaw in common approaches | Type | A1 Journal article | ||
| Year | 2018 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 20 | Issue | 13 | Pages | 8456-8459 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | A number of recent computational material design studies based on density functional theory (DFT) calculations have put forward a new class of materials with electrically switchable chemical characteristics that can be exploited in the development of tunable gas storage and electrocatalytic applications. We find systematic flaws in almost every computational study of gas adsorption on polarized or charged surfaces, stemming from an improper and unreproducible treatment of periodicity, leading to very large errors of up to 3 eV in some cases. Two simple corrective procedures that lead to consistent results are proposed, constituting a crucial course correction to the research in the field. | ||||
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| Language | Wos |
000428779700007 | Publication Date | 2018-03-12 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 8 | Open Access | OpenAccess |
| Notes | K. M. B. is funded as PhD fellow (aspirant) of the FWO-Flanders (Research Foundation – Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government – department EWI. | Approved | Most recent IF: 4.123 | ||
| Call Number | PLASMANT @ plasmant @c:irua:150357 | Serial | 4916 | ||
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| Author | Gorbanev, Y.; Verlackt, C.C.W.; Tinck, S.; Tuenter, E.; Foubert, K.; Cos, P.; Bogaerts, A. | ||||
| Title | Combining experimental and modelling approaches to study the sources of reactive species induced in water by the COST RF plasma jet | Type | A1 Journal article | ||
| Year | 2018 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 20 | Issue | 4 | Pages | 2797-2808 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | The vast biomedical potential of cold atmospheric pressure plasmas (CAPs) is governed by the formation of reactive species. These biologically active species are formed upon the interaction of CAPs with the surroundings. In biological milieu, water plays an essential role. The development of biomedical CAPs thus requires understanding of the sources of the reactive species in aqueous media exposed to the plasma. This is especially important in case of the COST RF plasma jet, which is developed as a reference microplasma system. In this work, we investigated the formation of the OH radicals, H atoms and H2O2 in aqueous solutions exposed to the COST plasma jet. This was done by combining experimental and modelling approaches. The liquid phase species were analysed using UV-Vis spectroscopy and spin trapping with hydrogen isotopes and electron paramagnetic resonance (EPR) spectroscopy. The discrimination between the species formed from the liquid phase and the gas phase molecules was performed by EPR and 1H-NMR analyses of the liquid samples. The concentrations of the reactive species in the gas phase plasma were obtained using a zero-dimensional (0D) chemical kinetics computational model. A three-dimensional (3D) fluid dynamics model was developed to provide information on the induced humidity in the plasma effluent. The comparison of the experimentally obtained trends for the formation of the species as a function of the feed gas and effluent humidity with the modelling results suggest that all reactive species detected in our system are mostly formed in the gas phase plasma inside the COST jet, with minor amounts arising from the plasma effluent humidity. | ||||
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| Language | Wos |
000423505500066 | Publication Date | 2018-01-05 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 23 | Open Access | OpenAccess |
| Notes | We are grateful to Volker Schulz-von der Gathen (Experimental Physics II: Application Oriented Plasma Physics, Ruhr-Universita¨t Bochum, Germany) for providing the COST RF plasma jet. We thank our colleagues at the University of Antwerp: Gilles Van Loon (Mechanical Workshop), Karen Leyssens (Research group PLASMANT), and Sylvia Dewilde (Department of Biomedical Sciences) for their help with the equipment. This work was funded by the European Marie Sklodowska-Curie Individual Fellowship ‘LTPAM’ within Horizon2020 (grant no. 657304). Stefan Tinck thanks the Fund for Scientific Research – Flanders (FWO) for supporting his work (grant no. 0880.212.840). | Approved | Most recent IF: 4.123 | ||
| Call Number | PLASMANT @ plasmant @c:irua:148365 | Serial | 4808 | ||
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| Author | Sanchez-Barriga, J.; Ogorodnikov, I.I.; Kuznetsov, M.V.; Volykhov, A.A.; Matsui, F.; Callaert, C.; Hadermann, J.; Verbitskiy, N.I.; Koch, R.J.; Varykhalov, A.; Rader, O.; Yashina, L.V. | ||||
| Title | Observation of hidden atomic order at the interface between Fe and topological insulator Bi2Te3 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 19 | Issue | 45 | Pages | 30520-30532 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | <script type='text/javascript'>document.write(unpmarked('To realize spintronic devices based on topological insulators (TIs), well-defined interfaces between magnetic metals and TIs are required. Here, we characterize atomically precisely the interface between the 3d transition metal Fe and the TI Bi2Te3 at different stages of its formation. Using photoelectron diffraction and holography, we show that after deposition of up to 3 monolayers Fe on Bi2Te3 at room temperature, the Fe atoms are ordered at the interface despite the surface disorder revealed by our scanning-tunneling microscopy images. We find that Fe occupies two different sites: a hollow adatom deeply relaxed into the Bi2Te3 quintuple layers and an interstitial atom between the third (Te) and fourth (Bi) atomic layers. For both sites, our core-level photoemission spectra and density-functional theory calculations demonstrate simultaneous chemical bonding of Fe to both Te and Bi atoms. We further show that upon deposition of Fe up to a thickness of 20 nm, the Fe atoms penetrate deeper into the bulk forming a 2-5 nm interface layer containing FeTe. In addition, excessive Bi is pushed down into the bulk of Bi2Te3 leading to the formation of septuple layers of Bi3Te4 within a distance of similar to 25 nm from the interface. Controlling the magnetic properties of the complex interface structures revealed by our work will be of critical importance when optimizing the efficiency of spin injection in TI-based devices.')); | ||||
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| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000416054400023 | Publication Date | 2017-10-24 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076; 1463-9084 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 4 | Open Access | OpenAccess |
| Notes | ; The authors acknowledge financial support within the bilateral program “Russian-German Laboratory at BESSY II” and thank Helmholtz Zentrum Berlin for granting access to the beamlines RGBL, UE112-PGM2a and U49-PGM1. The Supercomputing Center of Lomonosov Moscow State University is gratefully acknowledged for granting access to the “Lomonosov” supercomputer. The work was partially supported by DFG priority program SPP 1666, Impuls- und Vernetzungsfonds der Helmholtz-Gemeinschaft (Grant No. HRJRG-408) and Russian Foundation for Basic Research (Grants No. 13-02-91327 and No. 16-29-06410). C. C. acknowledges support from the University of Antwerp through the BOF grant 31445. The authors thank Dr Vera Neudachina, Daria Tsukanova, Dr Elmar Kataev and Dr Maria Batuk for their support during the XPS and TEM experiments. ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ lucian @ c:irua:147659 | Serial | 4888 | ||
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| Author | Momot, A.; Amini, M.N.; Reekmans, G.; Lamoen, D.; Partoens, B.; Slocombe, D.R.; Elen, K.; Adriaensens, P.; Hardy, A.; Van Bael, M.K. | ||||
| Title | A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 19 | Issue | 40 | Pages | 27866-27877 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | A combined experimental and first-principles study is performed to study the origin of conductivity in ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR) and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide evidence for the fact that the formed complex of AlZn and Zni corresponds to the origin of the Knight shifted peak (KS) we observe in 27Al NMR. As far as we know, the role of this complex has not been discussed in the literature to date. However, our first-principles calculations show that such a complex is indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly also form Zn clusters, leading to the observed increased conductivity. |
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| Language | Wos |
000413290500073 | Publication Date | 2017-10-09 | |
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| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 26 | Open Access | OpenAccess |
| Notes | We want to thank the Interuniversity Attraction Poles Programme (P7/05) initiated by the Belgian Science Policy Office (BELSPO) for the financial support. We also acknowledge the Research Foundation Flanders (FWO-Vlaanderen) for support via the MULTIMAR WOG project and under project No. G018914. The computational parts were carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules foundation and the Flemish Government (EWI Department). | Approved | Most recent IF: 4.123 | ||
| Call Number | EMAT @ emat @c:irua:146878 | Serial | 4760 | ||
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| Author | Dabaghmanesh, S.; Neek-Amal, M.; Partoens, B.; Neyts, E.C. | ||||
| Title | The formation of Cr2O3 nanoclusters over graphene sheet and carbon nanotubes | Type | A1 Journal article | ||
| Year | 2017 | Publication | Chemical physics letters | Abbreviated Journal | Chem Phys Lett |
| Volume | 687 | Issue | Pages | 188-193 | |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos |
000412453700030 | Publication Date | 2017-09-06 | |
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| ISSN | 0009-2614 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.815 | Times cited | 2 | Open Access | Not_Open_Access: Available from 01.11.2019 |
| Notes | ; This work was supported by SIM vzw, Technologiepark 935, BE-9052 Zwijnaarde, Belgium, within the InterPoCo project of the H-INT-S horizontal program. The computational resources and services used in this work were provided by the Vlaams Supercomputer Centrum (VSC) and the HPC infrastructure of the University of Antwerp. ; | Approved | Most recent IF: 1.815 | ||
| Call Number | UA @ lucian @ c:irua:146646 | Serial | 4795 | ||
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| Author | Dabaghmanesh, S.; Sarmadian, N.; Neyts, E.C.; Partoens, B. | ||||
| Title | A first principles study of p-type defects in LaCrO3 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 19 | Issue | 34 | Pages | 22870-22876 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Recently, Sr-doped LaCrO3 has been experimentally introduced as a new p-type transparent conducting oxide. It is demonstrated that substituting Sr for La results in inducing p-type conductivity in LaCrO3. Performing first principles calculations we study the electronic structure and formation energy of various point defects in LaCrO3. Our results for the formation energies show that in addition to Sr, two more divalent defects, Ca and Ba, substituting for La in LaCrO3, behave as shallow acceptors in line with previous experimental reports. We further demonstrate that under oxygen-poor growth conditions, these shallow acceptors will be compensated by intrinsic donor-like defects (an oxygen vacancy and Cr on an oxygen site), but in the oxygen-rich growth regime the shallow acceptors have the lowest formation energies between all considered defects and will lead to p-type conductivity. | ||||
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| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000408671600026 | Publication Date | 2017-08-01 | |
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| ISSN | 1463-9076; 1463-9084 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 16 | Open Access | OpenAccess |
| Notes | ; This work was supported by SIM vzw, Technologiepark 935, BE-9052 Zwijnaarde, Belgium, within the InterPoCo project of the H-INT-S horizontal program. The computational resources and services were provided by the Flemish Supercomputer Center and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government. ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ lucian @ c:irua:145621 | Serial | 4735 | ||
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| 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. | ||||
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000406334300034 | Publication Date | 2017-06-22 | |
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| ISSN | 1463-9076 | ISBN | 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 | ||
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| Author | Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. | ||||
| Title | Structural and electronic properties of defects at grain boundaries in CuInSe2 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 19 | Issue | 19 | Pages | 14770-14780 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported. |
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000403327200059 | Publication Date | 2017-05-12 | |
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| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 12 | Open Access | OpenAccess |
| Notes | We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 4.123 | ||
| Call Number | EMAT @ emat @ c:irua:143869 | Serial | 4577 | ||
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| Author | Loreto, S.; Cuypers, B.; Brokken, J.; Van Doorslaer, S.; De Wael, K.; Meynen, V. | ||||
| Title | The effect of the buffer solution on the adsorption and stability of horse heart myoglobin on commercial mesoporous titanium dioxide : a matter of the right choice | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 19 | Issue | 21 | Pages | 13503-13514 |
| Keywords | A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | Despite the numerous studies on the adsorption of different proteins onto mesoporous titanium dioxide and indications on the important role of buffer solutions in bioactivity, a systematic study on the impact of the buffer on the protein incorporation into porous substrates is still lacking. We here studied the interaction between a commercial mesoporous TiO2 and three of the most used buffers for protein incorporation, i.e. HEPES, Tris and phosphate buffer. In addition, this paper analyzes the adsorption of horse heart myoglobin (hhMb) onto commercial mesoporous TiO2 as a model system to test the influence of buffers on the protein incorporation behavior in mesoporous TiO2. N2 sorption analysis, FT-IR and TGA/DTG measurements were used to evaluate the interaction between the buffers and the TiO2 surface, and the effect of such an interaction on hhMb adsorption. Cyclic voltammetry (CV) and electron paramagnetic resonance (EPR) were used to detect changes in the microenvironment surrounding the heme. The three buffers show a completely different interaction with the TiO2 surface, which drastically affects the adsorption of myoglobin as well as its structure and electrochemical activity. Therefore, special attention is required while choosing the buffer medium to avoid misguided evaluation of protein adsorption on mesoporous TiO2. | ||||
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000402488300013 | Publication Date | 2017-04-27 | |
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| ISSN | 1463-9076; 1463-9084 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 2 | Open Access | |
| Notes | ; We are grateful to Gert Nuyts for performing the XRF measurements, and Dr Stanislav Trashin for his assistance during the electrochemical experiments. This work is supported by the Research Foundation – Flanders (FWO) (grant G.0687.13) and the University of Antwerp (BOF project). ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ admin @ c:irua:143514 | Serial | 5582 | ||
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| Author | Matsubara, M.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
| Title | Doping anatase TiO2with group V-b and VI-b transition metal atoms: a hybrid functional first-principles study | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 19 | Issue | 19 | Pages | 1945-1952 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | We investigate the role of transition metal atoms of group V-b (V, Nb, Ta) and VI-b (Cr, Mo, W) as n- or p-type dopants in anatase TiO$2$ using thermodynamic principles and density functional theory with the Heyd-Scuseria-Ernzerhof HSE06 hybrid functional. The HSE06 functional provides a realistic value for the band gap, which ensures a correct classification of dopants as shallow or deep donors or acceptors. Defect formation energies and thermodynamic transition levels are calculated taking into account the constraints imposed by the stability of TiO$2$ and the solubility limit of the impurities. Nb, Ta, W and Mo are identified as shallow donors. Although W provides two electrons, Nb and Ta show a considerable lower formation energy, in particular under O-poor conditions. Mo donates in principle one electron, but under specific conditions can turn into a double donor. V impurities are deep donors and Cr shows up as an amphoteric defect, thereby acting as an electron trapping center in n-type TiO$_2$ especially under O-rich conditions. A comparison with the available experimental data yields excellent agreement. |
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| Language | Wos |
000394426400027 | Publication Date | 2016-12-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 19 | Open Access | OpenAccess |
| Notes | We gratefully acknowledge financial support from the IWTVlaanderenthrough projects G.0191.08 and G.0150.13, and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, which is funded by the Hercules foundation. M. M. acknowledges financial support from the GOA project ‘‘XANES meets ELNES’’ of the University of Antwerp. | Approved | Most recent IF: 4.123 | ||
| Call Number | EMAT @ emat @ c:irua:140835 | Serial | 4421 | ||
| Permanent link to this record | |||||
| Author | Iyikanat, F.; Senger, R.T.; Peeters, F.M.; Sahin, H. | ||||
| Title | Quantum-Transport Characteristics of a p-n Junction on Single-Layer TiS3 | Type | A1 Journal article | ||
| Year | 2016 | Publication | ChemPhysChem : a European journal of chemical physics and physical chemistry | Abbreviated Journal | Chemphyschem |
| Volume | 17 | Issue | 17 | Pages | 3985-3991 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | By using density functional theory and non-equilibrium Green's function-based methods, we investigated the electronic and transport properties of a TiS3 monolayer p-n junction. We constructed a lateral p-n junction on a TiS3 monolayer using Li and F adatoms. An applied bias voltage caused significant variability in the electronic and transport properties of the TiS3 p-n junction. In addition, the spin-dependent current-volt-age characteristics of the constructed TiS3 p-n junction were analyzed. Important device characteristics were found, such as negative differential resistance and rectifying diode behaviors for spin-polarized currents in the TiS3 p-n junction. These prominent conduction properties of the TiS3 p-n junction offer remarkable opportunities for the design of nanoelectronic devices based on a recently synthesized single-layered material. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Weinheim | Editor | ||
| Language | Wos |
000389534800018 | Publication Date | 2016-09-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1439-4235 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.075 | Times cited | 12 | Open Access | |
| Notes | ; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and the Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). FI, HS, and RTS acknowledge the support from TUBITAK Project No 114F397. H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. ; | Approved | Most recent IF: 3.075 | ||
| Call Number | UA @ lucian @ c:irua:140245 | Serial | 4458 | ||
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| Author | Dabaghmanesh, S.; Neyts, E.C.; Partoens, B. | ||||
| Title | van der Waals density functionals applied to corundum-type sesquioxides : bulk properties and adsorption of CH3 and C6H6 on (0001) surfaces | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 23139-23146 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | van der Waals (vdW) forces play an important role in the adsorption of molecules on the surface of solids. However, the choice of the most suitable vdW functional for different systems is an essential problem which must be addressed for different systems. The lack of a systematic study on the performance of the vdW functionals in the bulk and adsorption properties of metal-oxides motivated us to examine different vdW approaches and compute the bulk and molecular adsorption properties of alpha-Cr2O3, alpha-Fe2O3, and alpha-Al2O3. For the bulk properties, we compared our results for the heat of formation, cohesive energy, lattice parameters and bond distances between the different vdW functionals and available experimental data. Next we studied the adsorption of benzene and CH3 molecules on top of different oxide surfaces. We employed different approximations to exchange and correlation within DFT, namely, the Perdew-Burke-Ernzerhof (PBE) GGA, (PBE)+U, and vdW density functionals [ DFT(vdW-DF/DF2/optPBE/optB86b/optB88)+U] as well as DFT-D2/D3(+U) methods of Grimme for the bulk calculations and optB86b-vdW(+U) and DFT-D2(+U) for the adsorption energy calculations. Our results highlight the importance of vdW interactions not only in the adsorption of molecules, but importantly also for the bulk properties. Although the vdW contribution in the adsorption of CH3 (as a chemisorption interaction) is less important compared to the adsorption of benzene (as a physisorption interaction), this contribution is not negligible. Also adsorption of benzene on ferryl/chromyl terminated surfaces shows an important chemisorption contribution in which the vdW interactions become less significant. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000382109300040 | Publication Date | 2016-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076; 1463-9084 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 6 | Open Access | |
| Notes | ; This work was supported by the Strategic Initiative Materials in Flanders (SIM). The computational resources and services used in this work were provided by the Vlaams Supercomputer Centrum (VSC) and the HPC infrastructure of the University of Antwerp. ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ lucian @ c:irua:135701 | Serial | 4311 | ||
| Permanent link to this record | |||||
| Author | Bercx, M.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
| Title | First-principles analysis of the spectroscopic limited maximum efficiency of photovoltaic absorber layers for CuAu-like chalcogenides and silicon | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 20542-20549 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | Chalcopyrite semiconductors are of considerable interest for application as absorber layers in thin-film photovoltaic cells. When growing films of these compounds, however, they are often found to contain CuAu-like domains, a metastable phase of chalcopyrite. It has been reported that for CuInS2, the presence of the CuAu-like phase improves the short circuit current of the chalcopyrite-based photovoltaic cell. We investigate the thermodynamic stability of both phases for a selected list of I-III-VI2 materials using a first-principles density functional theory approach. For the CuIn-VI2 compounds, the difference in formation energy between the chalcopyrite and CuAu-like phase is found to be close to 2 meV per atom, indicating a high likelihood of the presence of CuAu-like domains. Next, we calculate the spectroscopic limited maximum efficiency (SLME) of the CuAu-like phase and compare the results with those of the corresponding chalcopyrite phase. We identify several candidates with a high efficiency, such as CuAu-like CuInS2, for which we obtain an SLME of 29% at a thickness of 500 nm. We observe that the SLME can have values above the Shockley-Queisser (SQ) limit, and show that this can occur because the SQ limit assumes the absorptivity to be a step function, thus overestimating the radiative recombination in the detailed balance approach. This means that it is possible to find higher theoretical efficiencies within this framework simply by calculating the J-V characteristic with an absorption spectrum. Finally, we expand our SLME analysis to indirect band gap absorbers by studying silicon, and find that the SLME quickly overestimates the reverse saturation current of indirect band gap materials, drastically lowering their calculated efficiency. | ||||
| Address | EMAT & CMT groups, Department of Physics, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171, 2020 Antwerp, Belgium. marnik.bercx@uantwerpen.be | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Wos |
000381428600058 | Publication Date | 2016-07-08 |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 34 | Open Access | |
| Notes | We acknowledge financial support of FWO-Vlaanderen through projects G.0150.13N and G.0216.14N and ERA-NET RUS Plus/FWO, Grant G0D6515N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO FWOVlaanderen. | Approved | Most recent IF: 4.123 | ||
| Call Number | c:irua:135091 | Serial | 4112 | ||
| Permanent link to this record | |||||
| Author | Nikolaev, A.V.; Lamoen, D.; Partoens, B. | ||||
| Title | Extension of the basis set of linearized augmented plane wave (LAPW) method by using supplemented tight binding basis functions | Type | A1 Journal article | ||
| Year | 2016 | Publication | The journal of chemical physics | Abbreviated Journal | J Chem Phys |
| Volume | 145 | Issue | 145 | Pages | 014101 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | In order to increase the accuracy of the linearized augmented plane wave (LAPW) method, we present a new approach where the plane wave basis function is augmented by two different atomic radial components constructed at two different linearization energies corresponding to two different electron bands (or energy windows). We demonstrate that this case can be reduced to the standard treatment within the LAPW paradigm where the usual basis set is enriched by the basis functions of the tight binding type, which go to zero with zero derivative at the sphere boundary. We show that the task is closely related with the problem of extended core states which is currently solved by applying the LAPW method with local orbitals (LAPW+LO). In comparison with LAPW+LO, the number of supplemented basis functions in our approach is doubled, which opens up a new channel for the extension of the LAPW and LAPW+LO basis sets. The appearance of new supplemented basis functions absent in the LAPW+LO treatment is closely related with the existence of the ul-component in the canonical LAPW method. We discuss properties of additional tight binding basis functions and apply the extended basis set for computation of electron energy bands of lanthanum (face and body centered structures) and hexagonal close packed lattice of cadmium. We demonstrate that the new treatment gives lower total energies in comparison with both canonical LAPW and LAPW+LO, with the energy difference more pronounced for intermediate and poor LAPW basis sets. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos |
000379584700003 | Publication Date | 2016-07-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-9606 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.965 | Times cited | 11 | Open Access | |
| Notes | A.V.N. acknowledges useful discussions with B. Verberck, E. V. Tkalya, and A. V. Bibikov. | Approved | Most recent IF: 2.965 | ||
| Call Number | c:irua:134290 | Serial | 4099 | ||
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| Author | Aierken, Y.; Leenaerts, O.; Peeters, F.M. | ||||
| Title | A first-principles study of stable few-layer penta-silicene | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 18486-18492 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Recently penta-graphene was proposed as a stable two-dimensional carbon allotrope consisting of a single layer of interconnected carbon pentagons [Zhang et al., PNAS, 2015, 112, 2372]. Its silicon counterpart, penta-silicene, however, is not stable. In this work, we show that multilayers of penta-silicene form stable materials with semiconducting or metallic properties, depending on the stacking mode. We demonstrate their dynamic stability through their phonon spectrum and using molecular dynamics. A particular type of bilayer penta-silicene is found to have lower energy than all of the known hexagonal silicene bilayers and forms therefore the most stable bilayer silicon material predicted so far. The electronic and mechanical properties of these new silicon allotropes are studied in detail and their behavior under strain is investigated. We demonstrate that strain can be used to tune its band gap. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000379486200077 | Publication Date | 2016-06-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 42 | Open Access | |
| Notes | ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ lucian @ c:irua:134942 | Serial | 4132 | ||
| Permanent link to this record | |||||
| Author | Aierken, Y.; Çakir, D.; Peeters, F.M. | ||||
| Title | Strain enhancement of acoustic phonon limited mobility in monolayer TiS3 | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 14434-14441 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Strain engineering is an effective way to tune the intrinsic properties of a material. Here, we show by using first-principles calculations that both uniaxial and biaxial tensile strain applied to monolayer TiS3 are able to significantly modify its intrinsic mobility. From the elastic modulus and the phonon dispersion relation we determine the tensile strain range where structure dynamical stability of the monolayer is guaranteed. Within this region, we find more than one order of enhancement of the acoustic phonon limited mobility at 300 K (100 K), i.e. from 1.71 x 10(4) (5.13 x 10(4)) cm(2) V-1 s(-1) to 5.53 x 10(6) (1.66 x 10(6)) cm(2) V-1 s(-1). The degree of anisotropy in both mobility and effective mass can be tuned by using tensile strain. Furthermore, we can either increase or decrease the band gap of TiS3 monolayer by applying strain along different crystal directions. This property allows us to use TiS3 not only in electronic but also in optical applications. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000378102700036 | Publication Date | 2016-05-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 24 | Open Access | |
| Notes | ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-V1). Computational resources were provided by HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation and the Flemish Government-department EWI. ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ lucian @ c:irua:134628 | Serial | 4250 | ||
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| Author | Filez, M.; Redekop, E.A.; Galvita, V.V.; Poelman, H.; Meledina, M.; Turner, S.; Van Tendeloo, G.; Bell, A.T.; Marin, G.B. | ||||
| Title | The role of hydrogen during Pt-Ga nanocatalyst formation | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 3234-3243 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Hydrogen plays an essential role during the in situ assembly of tailored catalytic materials, and serves as key ingredient in multifarious chemical reactions promoted by these catalysts. Despite intensive debate for several decades, the existence and nature of hydrogen-involved mechanisms – such as hydrogen-spillover, surface migration – have not been unambiguously proven and elucidated up to date. Here, Pt-Ga alloy formation is used as a probe reaction to study the behavior and atomic transport of H and Ga, starting from Pt nanoparticles on hydrotalcite-derived Mg(Ga)(Al)Ox supports. In situ XANES spectroscopy, time-resolved TAP kinetic experiments, HAADF-STEM imaging and EDX mapping are combined to probe Pt, Ga and H in a series of H2 reduction experiments up to 650 degrees C. Mg(Ga)(Al)Ox by itself dissociates hydrogen, but these dissociated hydrogen species do not induce significant reduction of Ga3+ cations in the support. Only in the presence of Pt, partial reduction of Ga3+ into Gadelta+ is observed, suggesting that different reaction mechanisms dominate for Pt- and Mg(Ga)(Al)Ox-dissociated hydrogen species. This partial reduction of Ga3+ is made possible by Pt-dissociated H species which spillover onto non-reducible Mg(Al)Ox or partially reducible Mg(Ga)(Al)Ox and undergo long-range transport over the support surface. Moderately mobile Gadelta+Ox migrates towards Pt clusters, where Gadelta+ is only fully reduced to Ga0 on condition of immediate stabilization inside Pt-Ga alloyed nanoparticles. | ||||
| Address | Laboratory for Chemical Technology (LCT), Ghent University, Technologiepark 914, B-9052 Ghent, Belgium. hilde.poelman@ugent.be | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Wos |
000369506000106 | Publication Date | 2016-01-04 |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 10 | Open Access | |
| Notes | This work was supported by the Fund for Scientific Research Flanders (FWO: G.0209.11), the ‘Long Term Structural Methusalem Funding by the Flemish Government’, the IAP 7/05 Interuniversity Attraction Poles Programme – Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of beam time at the DUBBLE beam line of the ESRF and travel costs and a postdoctoral fellowship for S.T. The authors acknowledge the assistance from D. Banerjee (XAS campaign 26-01-979) at DUBBLE. E. A. Redekop acknowledges the Marie Curie International Incoming Fellowship granted by the European Commission (Grant Agreement No. 301703). The authors also express their gratitude to V. Bliznuk for acquisition of the TEM images. | Approved | Most recent IF: 4.123 | ||
| Call Number | c:irua:132315 | Serial | 4000 | ||
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| Author | Yagmurcukardes, M.; Horzum, S.; Torun, E.; Peeters, F.M.; Senger, R.T. | ||||
| Title | Nitrogenated, phosphorated and arsenicated monolayer holey graphenes | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 3144-3150 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Motivated by a recent experiment that reported the synthesis of a new 2D material nitrogenated holey graphene (C2N) [Mahmood et al., Nat. Commun., 2015, 6, 6486], the electronic, magnetic, and mechanical properties of nitrogenated (C2N), phosphorated (C2P) and arsenicated (C2As) monolayer holey graphene structures are investigated using first-principles calculations. Our total energy calculations indicate that, similar to the C2N monolayer, the formation of the other two holey structures are also energetically feasible. Calculated cohesive energies for each monolayer show a decreasing trend going from the C2N to C2As structure. Remarkably, all the holey monolayers considered are direct band gap semiconductors. Regarding the mechanical properties (in-plane stiffness and Poisson ratio), we find that C2N has the highest in-plane stiffness and the largest Poisson ratio among the three monolayers. In addition, our calculations reveal that for the C2N, C2P and C2As monolayers, creation of N and P defects changes the semiconducting behavior to a metallic ground state while the inclusion of double H impurities in all holey structures results in magnetic ground states. As an alternative to the experimentally synthesized C2N, C2P and C2As are mechanically stable and flexible semiconductors which are important for potential applications in optoelectronics. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000369506000095 | Publication Date | 2015-12-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 36 | Open Access | |
| Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ lucian @ c:irua:132313 | Serial | 4214 | ||
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| Author | Ali, S.; Myasnichenko, V.S.; Neyts, E.C. | ||||
| Title | Size-dependent strain and surface energies of gold nanoclusters | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 792-800 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Gold nanocluster properties exhibit unique size-dependence. In this contribution, we employ reactive molecular dynamics simulations to calculate the size- and temperature-dependent surface energies, strain energies and atomic displacements for icosahedral, cuboctahedral, truncated octahedral and decahedral Au-nanoclusters. The calculations demonstrate that the surface energy decreases with increasing cluster size at 0 K but increases with size at higher temperatures. The calculated melting curves as a function of cluster size demonstrate the Gibbs-Thomson effect. Atomic displacements and strain are found to strongly depend on the cluster size and both are found to increase with increasing cluster size. These results are of importance for understanding the size-and temperature-dependent surface processes on gold nanoclusters. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000369480600017 | Publication Date | 2015-11-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 37 | Open Access | |
| Notes | Approved | Most recent IF: 4.123 | |||
| Call Number | UA @ lucian @ c:irua:131626 | Serial | 4243 | ||
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| Author | Calizzi, M.; Venturi, F.; Ponthieu, M.; Cuevas, F.; Morandi, V.; Perkisas, T.; Bals, S.; Pasquini, L. | ||||
| Title | Gas-phase synthesis of Mg-Ti nanoparticles for solid-state hydrogen storage | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 18 | Issue | 18 | Pages | 141-148 |
| Keywords | A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) | ||||
| Abstract | Mg-Ti nanostructured samples with different Ti contents were prepared via compaction of nanoparticles grown by inert gas condensation with independent Mg and Ti vapour sources. The growth set-up offered the option to perform in situ hydrogen absorption before compaction. Structural and morphological characterisation was carried out by X-ray diffraction, energy dispersive spectroscopy and electron microscopy. The formation of an extended metastable solid solution of Ti in hcp Mg was detected up to 15 at% Ti in the as-grown nanoparticles, while after in situ hydrogen absorption, phase separation between MgH2 and TiH2 was observed. At a Ti content of 22 at%, a metastable Mg-Ti-H fcc phase was observed after in situ hydrogen absorption. The co-evaporation of Mg and Ti inhibited nanoparticle coalescence and crystallite growth in comparison with the evaporation of Mg only. In situ hydrogen absorption was beneficial to subsequent hydrogen behaviour, studied by high pressure differential scanning calorimetry and isothermal kinetics. A transformed fraction of 90% was reached within 100 s at 300 degrees C during both hydrogen absorption and desorption. The enthalpy of hydride formation was not observed to differ from bulk MgH2. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000368755500014 | Publication Date | 2015-11-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 31 | Open Access | Not_Open_Access |
| Notes | ; Part of this work was supported by the COST Action MP1103 “Nanostructured materials for solid-state hydrogen storage”. ; | Approved | Most recent IF: 4.123 | ||
| Call Number | UA @ lucian @ c:irua:131589 | Serial | 4184 | ||
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| Author | Kang, J.; Sahin, H.; Peeters, F.M. | ||||
| Title | Mechanical properties of monolayer sulphides : a comparative study between MoS2, HfS2 and TiS3 | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 17 | Issue | 17 | Pages | 27742-27749 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The in-plane stiffness (C), Poisson's ratio (nu), Young's modulus and ultimate strength (sigma) along two different crystallographic orientations are calculated for the single layer crystals: MoS2, HfS2 and TiS3 in 1H, 1T and monoclinic phases. We find that MoS2 and HfS2 have isotropic in-plane stiffnesses of 124.24 N m(-1) and 79.86 N m(-1), respectively. While for TiS3 the in-plane stiffness is highly anisotropic due to its monoclinic structure, with C-x = 83.33 N m(-1) and C-y = 133.56 N m(-1) (x and y are parallel to its longer and shorter in-plane lattice vectors.). HfS2 which is in the 1T phase has the smallest anisotropy in its ultimate strength, whereas TiS3 in the monoclinic phase has the largest. Along the armchair direction MoS2 has the largest sigma of 23.48 GPa, whereas along y TiS3 has the largest sigma of 18.32 GPa. We have further analyzed the band gap response of these materials under uniaxial tensile strain, and find that they exhibit different behavior. Along both armchair and zigzag directions, the band gap of MoS2 (HfS2) decreases (increases) as strain increases, and the response is almost isotropic. For TiS3, the band gap decreases when strain is along x, while if strain is along y, the band gap increases first and then decreases beyond a threshold strain value. The different characteristics observed in these sulphides with different structures shed light on the relationship between the structure and properties, which is useful for applications in nanotechnology. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000363193800055 | Publication Date | 2015-09-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 83 | Open Access | |
| Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Super-computer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. ; | Approved | Most recent IF: 4.123; 2015 IF: 4.493 | ||
| Call Number | UA @ lucian @ c:irua:129478 | Serial | 4204 | ||
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| Author | Çakir, D.; Peeters, F.M. | ||||
| Title | Fluorographane : a promising material for bipolar doping of MoS2 | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 17 | Issue | 17 | Pages | 27636-27641 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Using first principles calculations we investigate the structural and electronic properties of interfaces between fluorographane and MoS2. Unsymmetrical functionalization of graphene with H and F results in an intrinsic dipole moment perpendicular to the plane of the buckled graphene skeleton. Depending on the orientation of this dipole moment, the electronic properties of a physically absorbed MoS2 monolayer can be switched from n-to p-type or vice versa. We show that one can realize vanishing n-type/p-type Schottky barrier heights when contacting MoS2 to fluorographane. By applying a perpendicular electric field, the size of the Schottky barrier and the degree of doping can be tuned. Our calculations indicate that a fluorographane monolayer is a promising candidate for bipolar doping of MoS2, which is vital in the design of novel technological applications based on two-dimensional materials. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000363193800043 | Publication Date | 2015-09-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 7 | Open Access | |
| Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. ; | Approved | Most recent IF: 4.123; 2015 IF: 4.493 | ||
| Call Number | UA @ lucian @ c:irua:129477 | Serial | 4182 | ||
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| Author | Çakir, D.; Kecik, D.; Sahin, H.; Durgun, E.; Peeters, F.M. | ||||
| Title | Realization of a p-n junction in a single layer boron-phosphide | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 17 | Issue | 17 | Pages | 13013-13020 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Two-dimensional (2D) materials have attracted growing interest due to their potential use in the next generation of nanoelectronic and optoelectronic applications. On the basis of first-principles calculations based on density functional theory, we first investigate the electronic and mechanical properties of single layer boron phosphide (h-BP). Our calculations show that h-BP is a mechanically stable 2D material with a direct band gap of 0.9 eV at the K-point, promising for both electronic and optoelectronic applications. We next investigate the electron transport properties of a p-n junction constructed from single layer boron phosphide (h-BP) using the non-equilibrium Green's function formalism. The n-and p-type doping of BP are achieved by substitutional doping of B with C and P with Si, respectively. C(Si) substitutional doping creates donor (acceptor) states close to the conduction (valence) band edge of BP, which are essential to construct an efficient p-n junction. By modifying the structure and doping concentration, it is possible to tune the electronic and transport properties of the p-n junction which exhibits not only diode characteristics with a large current rectification but also negative differential resistance (NDR). The degree of NDR can be easily tuned via device engineering. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000354195300065 | Publication Date | 2015-04-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076;1463-9084; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 104 | Open Access | |
| Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem foundation of the Flemish government and the Bilateral program FWO-TUBITAK (under the Project No. 113T050) between Flanders and Turkey. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. D.C. is supported by a FWO Pegasus-short Marie Curie Fellowship. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship. E.D. acknowledges support from Bilim Akademisi – The Science Academy, Turkey under the BAGEP program. ; | Approved | Most recent IF: 4.123; 2015 IF: 4.493 | ||
| Call Number | c:irua:126394 | Serial | 2835 | ||
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| Author | Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. | ||||
| Title | The role of the VZn-NO-H complex in the p-type conductivity in ZnO | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 17 | Issue | 17 | Pages | 5485-5489 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000349616400080 | Publication Date | 2015-01-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076;1463-9084; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 20 | Open Access | |
| Notes | FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules | Approved | Most recent IF: 4.123; 2015 IF: 4.493 | ||
| Call Number | c:irua:123218 | Serial | 3592 | ||
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| Author | Euan-Diaz, E.; Herrera-Velarde, S.; Misko, V.R.; Peeters, F.M.; Castaneda-Priego, R. | ||||
| Title | Structural transitions and long-time self-diffusion of interacting colloids confined by a parabolic potential | Type | A1 Journal article | ||
| Year | 2015 | Publication | The journal of chemical physics | Abbreviated Journal | J Chem Phys |
| Volume | 142 | Issue | 142 | Pages | 024902 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We report on the ordering and dynamics of interacting colloidal particles confined by a parabolic potential. By means of Brownian dynamics simulations, we find that by varying the magnitude of the trap stiffness, it is possible to control the dimension of the system and, thus, explore both the structural transitions and the long-time self-diffusion coefficient as a function of the degree of confinement. We particularly study the structural ordering in the directions perpendicular and parallel to the confinement. Further analysis of the local distribution of the first-neighbors layer allows us to identify the different structural phases induced by the parabolic potential. These results are summarized in a structural state diagram that describes the way in which the colloidal suspension undergoes a structural re-ordering while increasing the confinement. To fully understand the particle dynamics, we take into account hydrodynamic interactions between colloids; the parabolic potential constricts the available space for the colloids, but it does not act on the solvent. Our findings show a non-linear behavior of the long-time self-diffusion coefficient that is associated to the structural transitions induced by the external field. (C) 2015 AIP Publishing LLC. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos |
000348129700053 | Publication Date | 2015-01-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-9606;1089-7690; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.965 | Times cited | 7 | Open Access | |
| Notes | ; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), PIFI 3.4 – PROMEP, and CONACyT (Grant Nos. 61418/2007, 102339/2008, Ph.D. scholarship 230171/2010). R.C.-P. also acknowledges financial support provided by the Marcos Moshinsky fellowship 2013-2014. The authors also thank to the General Coordination of Information and Communications Technologies (CGSTIC) at Cinvestav for providing HPC resources on the Hybrid Cluster Super-computer Xiuhcoatl, which have contributed partially to the research results reported in this paper. ; | Approved | Most recent IF: 2.965; 2015 IF: 2.952 | ||
| Call Number | c:irua:123832 | Serial | 3267 | ||
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| Author | Bal, K.M.; Neyts, E.C. | ||||
| Title | On the time scale associated with Monte Carlo simulations | Type | A1 Journal article | ||
| Year | 2014 | Publication | The journal of chemical physics | Abbreviated Journal | J Chem Phys |
| Volume | 141 | Issue | 20 | Pages | 204104 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Uniform-acceptance force-bias Monte Carlo (fbMC) methods have been shown to be a powerful technique to access longer timescales in atomistic simulations allowing, for example, phase transitions and growth. Recently, a new fbMC method, the time-stamped force-bias Monte Carlo (tfMC) method, was derived with inclusion of an estimated effective timescale; this timescale, however, does not seem able to explain some of the successes the method. In this contribution, we therefore explicitly quantify the effective timescale tfMC is able to access for a variety of systems, namely a simple single-particle, one-dimensional model system, the Lennard-Jones liquid, an adatom on the Cu(100) surface, a silicon crystal with point defects and a highly defected graphene sheet, in order to gain new insights into the mechanisms by which tfMC operates. It is found that considerable boosts, up to three orders of magnitude compared to molecular dynamics, can be achieved for solid state systems by lowering of the apparent activation barrier of occurring processes, while not requiring any system-specific input or modifications of the method. We furthermore address the pitfalls of using the method as a replacement or complement of molecular dynamics simulations, its ability to explicitly describe correct dynamics and reaction mechanisms, and the association of timescales to MC simulations in general. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos |
000345641400005 | Publication Date | 2014-11-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-9606;1089-7690; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.965 | Times cited | 26 | Open Access | |
| Notes | Approved | Most recent IF: 2.965; 2014 IF: 2.952 | |||
| Call Number | UA @ lucian @ c:irua:120667 | Serial | 2459 | ||
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| Author | Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
| Title | Native point defects in CuIn1-xGaxSe2 : hybrid density functional calculations predict the origin of p- and n-type conductivity | Type | A1 Journal article | ||
| Year | 2014 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 16 | Issue | 40 | Pages | 22299-22308 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | We have performed a first-principles study of the p- and n-type conductivity in CuIn1−xGaxSe2 due to native point defects, based on the HSE06 hybrid functional. Band alignment shows that the band gap becomes larger with x due to the increasing conduction band minimum, rendering it hard to establish n-type conductivity in CuGaSe2. From the defect formation energies, we find that In/GaCu is a shallow donor, while VCu, VIn/Ga and CuIn/Ga act as shallow acceptors. Using the total charge neutrality of ionized defects and intrinsic charge carriers to determine the Fermi level, we show that under In-rich growth conditions InCu causes strongly n-type conductivity in CuInSe2. Under increasingly In-poor growth conditions, the conductivity type in CuInSe2 alters to p-type and compensation of the acceptors by InCu reduces, as also observed in photoluminescence experiments. In CuGaSe2, the native acceptors pin the Fermi level far away from the conduction band minimum, thus inhibiting n-type conductivity. On the other hand, CuGaSe2 shows strong p-type conductivity under a wide range of Ga-poor growth conditions. Maximal p-type conductivity in CuIn1−xGaxSe2 is reached under In/Ga-poor growth conditions, in agreement with charge concentration measurements on samples with In/Ga-poor stoichiometry, and is primarily due to the dominant acceptor CuIn/Ga. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos |
000343072800042 | Publication Date | 2014-09-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076;1463-9084; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 43 | Open Access | |
| Notes | ; We gratefully acknowledge financial support from the science fund FWO-Flanders through project G.0150.13. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules foundation and the Flemish Government (EWI Department). We also like to thank Prof. S. Siebentritt of the University of Luxembourg for a presentation of her work on GIGS during a visit to our research group and for helpful discussions of our results. ; | Approved | Most recent IF: 4.123; 2014 IF: 4.493 | ||
| Call Number | UA @ lucian @ c:irua:120465 | Serial | 2284 | ||
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| Author | Proost, J.; Blaffart, F.; Turner, S.; Idrissi, H. | ||||
| Title | On the Origin of Damped Electrochemical Oscillations at Silicon Anodes (Revisited) | Type | A1 Journal article | ||
| Year | 2014 | Publication | ChemPhysChem : a European journal of chemical physics and physical chemistry | Abbreviated Journal | Chemphyschem |
| Volume | 15 | Issue | 14 | Pages | 3116-3124 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Electrochemical oscillations accompanying the formation of anodic silica have been shown in the past to be correlated with rather abrupt changes in the mechanical stress state of the silica film, commonly associated with some kind of fracture or porosification of the oxide. To advance the understanding on the origin of such oscillations in fluoride-free electrolytes, we have revisited a seminal experiment reported by Lehmann almost two decades ago. We thereby demonstrate that the oscillations are not stress-induced, and do not originate from a morphological transformation of the oxide in the course of anodisation. Alternatively, the mechanical features accompanying the oscillations can be explained by a partial relaxation of the field-induced electrostrictive stress. Furthermore, our observations suggest that the oscillation mechanism more likely results from a periodic depolarisation of the anodic silica. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Weinheim | Editor | ||
| Language | Wos |
000342770500029 | Publication Date | 2014-08-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1439-4235; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.075 | Times cited | 5 | Open Access | |
| Notes | Approved | Most recent IF: 3.075; 2014 IF: 3.419 | |||
| Call Number | UA @ lucian @ c:irua:121086 | Serial | 2444 | ||
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