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Author Van Duppen, B.; Tomadin, A.; Grigorenko, A.N.; Polini, M.
Title Current-induced birefringent absorption and non-reciprocal plasmons in graphene Type A1 Journal article
Year 2016 Publication 2D materials Abbreviated Journal 2D Mater
Volume 3 Issue 3 Pages 015011
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present extensive calculations of the optical and plasmonic properties of a graphene sheet carrying a dc current. By calculating analytically the density-density response function of current-carrying states at finite temperature, we demonstrate that an applied dc current modifies the Pauli blocking mechanism and that absorption acquires a birefringent character with respect to the angle between the in-plane light polarization and current flow. Employing the random phase approximation at finite temperature, we show that graphene plasmons display a degree of non-reciprocity and collimation that can be tuned with the applied current. We discuss the possibility to measure these effects.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000373936300031 Publication Date 2016-02-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-1583 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 6.937 Times cited 5 Open Access
Notes This work was supported by the EC under the Graphene Flagship program (contract no. CNECT- ICT-604391) and MIUR through the program ‘Pro- getti Premiali 2012’ – Project ‘ABNANOTECH’. B.V. D. wishes to thank the Scuola Normale Superiore (Pisa, Italy) for the kind hospitality while this work was carried out and Research Foundation Flanders (FWO- Vl) for a PhD Fellowship. Approved Most recent IF: 6.937
Call Number c:irua:131900 c:irua:131900 Serial 4017
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Author Schryvers, D.; Ma, Y.
Title In-situ TEM study of the Ni5Al3 to B2 + L12 decomposition in Ni65Al35 Type A1 Journal article
Year 1995 Publication Materials letters Abbreviated Journal Mater Lett
Volume 23 Issue Pages 105-111
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Homogenised and quenched Ni65Al35 samples were heated and studied in situ in a CM20 electron microscope up to 900 degrees C. The Ni5Al3 phase first forming around 550 degrees C in the quenched L1(0) microtwinned martensite starts to decompose around 800 degrees C yielding B2 precipitates in a twinned L1(2) matrix. The latter twinning is a remainder of the microtwinning in the original room temperature martensite. Also the crystallographic relations between precipitates and matrix can be traced back to the original formation of twinned martensite plates within the austenite. Some aspects of the dynamics of the process are discussed on the basis of snap shots and video recordings.
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Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1995QW53500020 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-577X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.489 Times cited 5 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:13166 Serial 1585
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Author Ozaydin, H.D.; Sahin, H.; Kang, J.; Peeters, F.M.; Senger, R.T.
Title Electronic and magnetic properties of 1T-TiSe2 nanoribbons Type A1 Journal article
Year 2015 Publication 2D materials Abbreviated Journal 2D Mater
Volume 2 Issue 2 Pages 044002
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Motivated by the recent synthesis of single layer TiSe2, we used state-of-the-art density functional theory calculations, to investigate the structural and electronic properties of zigzag and armchair-edged nanoribbons (NRs) of this material. Our analysis reveals that, differing from ribbons of other ultra-thin materials such as graphene, TiSe2 NRs have some distinctive properties. The electronic band gap of the NRs decreases exponentially with the width and vanishes for ribbons wider than 20 angstrom. For ultranarrow zigzag-edged NRs we find odd-even oscillations in the band gap width, although their band structures show similar features. Moreover, our detailed magnetic-ground-state analysis reveals that zigzag and armchair edged ribbons have non-magnetic ground states. Passivating the dangling bonds with hydrogen at the edges of the structures influences the band dispersion. Our results shed light on the characteristic properties of T phase NRs of similar crystal structures.
Address
Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000368936600005 Publication Date 2015-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-1583 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 6.937 Times cited 20 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 ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus Short Marie Curie Fellowship. HDO, HS and RTS acknowledge the support from TUBITAK through project 114F397. ; Approved Most recent IF: 6.937; 2015 IF: NA
Call Number UA @ lucian @ c:irua:131602 Serial 4169
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Author Fedotov, S.S.; Khasanova, N.R.; Samarin, A.S.; Drozhzhin, O.A.; Batuk, D.; Karakulina, O.M.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V.
Title AVPO4F (A = Li, K): A 4 V Cathode Material for High-Power Rechargeable Batteries Type A1 Journal article
Year 2016 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 28 Issue 28 Pages 411-415
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A novel potassium-based fluoride-phosphate, KVPO4F, with a KTiOPO4 (KTP) type structure is synthesized and characterized. About 85% of potassium has been electrochemically extracted on oxidation producing a cathode material with attractive performance for Li-ion batteries. The material operates at the electrode potential near 4V vs Li/Li+ exhibiting a sloping voltage profile, extremely low polarization, small volume change of about 2% and excellent rate capability, maintaining more than 75% of the initial capacity at 40C discharge rate without significant fading.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368949900002 Publication Date 2016-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 46 Open Access
Notes The authors kindly thank Dr. S. N. Putilin for XRD measurements, Dr. O. A. Shlyakhtin for the assistance in cryochemical synthesis, Ph.D. students A. A. Sadovnikov and E. A. Karpukhina for SEM imaging and FTIR spectra respectively. The work was partly supported by Russian Science Foundation (grant 16-19-00190), Skoltech Center for Electrochemical Energy Storage and Moscow State University Devel-opment Program up to 2020. J. Hadermann, O.M. Karakulina and A.M. Abakumov acknowledge support from FWO under grant G040116N. Approved Most recent IF: 9.466
Call Number c:irua:131583 Serial 4001
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Author Cabral, L.R.E.; de Aquino, B.R.C.H.T.; de Souza Silva, C.C.; Milošević, M.V.; Peeters, F.M.
Title Two-shell vortex and antivortex dynamics in a Corbino superconducting disk Type A1 Journal article
Year 2016 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 93 Issue 93 Pages 014515
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We examine theoretically the dynamics of two vortex shells in pinning-free superconducting thin disks in the Corbino geometry. In the first considered case, the inner shell is composed of vortices and the outer one of antivortices, corresponding to a state induced by the stray field of an off-plane magnetic dipole placed on top of the superconductor. In the second considered case, both shells comprise vortices induced by a homogeneous external field. We derive the equation of motion for each shell within the Bardeen-Stephen model and study the dynamics analytically by assuming both shells are rigid and commensurate. In both cases, two distinct regimes for vortex shell motion are identified: For low applied currents the entire configuration rotates rigidly, while above a threshold current the shells decouple from each other and rotate at different angular velocities. Analytical expressions for the decoupling current, the recombination time in the decoupled phases, as well as the voltage-current characteristics are presented. Our analytical results are in excellent agreement with numerical molecular dynamics simulations of the full many-vortex problem.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000368481600003 Publication Date 2016-01-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 7 Open Access
Notes ; This work was supported by the Brazilian Science Agencies CAPES, CNPq, and FACEPE under Grants No. APQ-1381-1.05/12, No. APQ 2017-1.05/12, and No. APQ-0598/1.05-08 and by EU-COST Action No. MP1201 and the Research Foundation-Flanders (FWO). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:131541 Serial 4270
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Author Brito, B.G.A.; Candido, L.; Hai, G.-Q.; Peeters, F.M.
Title Quantum effects in a free-standing graphene lattice : path-integral against classical Monte Carlo simulations Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 195416
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In order to study quantum effects in a two-dimensional crystal lattice of a free-standing monolayer graphene, we have performed both path-integral Monte Carlo (PIMC) and classical Monte Carlo (MC) simulations for temperatures up to 2000 K. The REBO potential is used for the interatomic interaction. The total energy, interatomic distance, root-mean-square displacement of the atom vibrations, and the free energy of the graphene layer are calculated. The obtained lattice vibrational energy per atom from the classical MC simulation is very close to the energy of a three-dimensional harmonic oscillator 3k(B)T. The PIMC simulation shows that quantum effects due to zero-point vibrations are significant for temperatures T < 1000 K. The quantum contribution to the lattice vibrational energy becomes larger than that of the classical lattice for T < 400 K. The lattice expansion due to the zero-point motion causes an increase of 0.53% in the lattice parameter. A minimum in the lattice parameter appears at T similar or equal to 500 K. Quantum effects on the atomic vibration amplitude of the graphene lattice and its free energy are investigated.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000368095400004 Publication Date 2015-11-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 22 Open Access
Notes ; This research was supported by the Brazilian agencies FAPESP, FAPEG, and CNPq, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:131144 Serial 4232
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Author Tahir, M.; Vasilopoulos, P.; Peeters, F.M.
Title Quantum magnetotransport properties of a MoS2 monolayer Type A1 Journal article
Year 2016 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 93 Issue 93 Pages 035406
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study transport properties of a MoS2 monolayer in the presence of a perpendicular magnetic field B. We derive and discuss its band structure and take into account spin and valley Zeeman effects. Compared to a conventional two-dimensional electron gas, these effects lead to new quantum Hall plateaus and new peaks in the longitudinal resistivity as functions of the magnetic field. The field B leads to a significant enhancement of the spin splitting in the conduction band, to a beating of the Shubnikov-de Haas (SdH) oscillations in the low-field regime, and to their splitting in the high-field regime. The Zeeman fields suppress significantly the beating of the SdH oscillations in the low-field regime and strongly enhance their splitting at high fields. The spin and valley polarizations show a similar beating pattern at low fields and are clearly separated at high fields in which they attain a value higher than 90%.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000367663500003 Publication Date 2016-01-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 42 Open Access
Notes ; This work was supported by the Canadian NSERC Grant No. OGP0121756 (M.T., P.V.) and by the Flemish Science Foundation (FWO-Vl) (F.M.P.). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:131093 Serial 4233
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Author Khalilov, U.; Yusupov, M.; Bogaerts, A.; Neyts, E.C.
Title Selective Plasma Oxidation of Ultrasmall Si Nanowires Type A1 Journal article
Year 2016 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 120 Issue 120 Pages 472-477
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Device performance of Si|SiOx core-shell based nanowires critically depends on the exact control over the oxide thickness. Low-temperature plasma oxidation is a highly promising alternative to thermal oxidation allowing for improved control over the oxidation process, in particular for ultrasmall Si nanowires. We here elucidate the room temperature plasma oxidation mechanisms of ultrasmall Si nanowires using hybrid molecular dynamics / force-bias Monte Carlo simulations. We demonstrate how the oxidation and concurrent water formation mechanisms are a function of the oxidizing plasma species and we demonstrate how the resulting core-shell oxide thickness can be controlled through these species. A new mechanism of water formation is discussed in detail. The results provide a detailed atomic level explanation of the oxidation process of highly curved Si surfaces. These results point out a route toward plasma-based formation of ultrathin core-shell Si|SiOx nanowires at room temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368562200057 Publication Date 2015-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 3 Open Access
Notes U.K. and M.Y. gratefully acknowledge financial support from the Research Foundation – Flanders (FWO), Grants 12M1315N and 1200216N. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. We thank Prof. A. C. T. van Duin for sharing the ReaxFF code. Approved Most recent IF: 4.536
Call Number c:irua:130677 Serial 4002
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Author Pouyet, E.; Cotte, M.; Fayard, B.; Salome, M.; Meirer, F.; Mehta, A.; Uffelman, E.S.; Hull, A.; Vanmeert, F.; Kieffer, J.; Burghammer, M.; Janssens, K.; Sette, F.; Mass, J.
Title 2D X-ray and FTIR micro-analysis of the degradation of cadmium yellow pigment in paintings of Henri Matisse Type A1 Journal article
Year 2015 Publication Applied physics A : materials science & processing Abbreviated Journal
Volume 121 Issue 3 Pages 967-980
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The chemical and physical alterations of cadmium yellow (CdS) paints in Henri Matisse's The Joy of Life (1905-1906, The Barnes Foundation) have been recognized since 2006, when a survey by portable X-ray fluorescence identified this pigment in all altered regions of the monumental painting. This alteration is visible as fading, discoloration, chalking, flaking, and spalling of several regions of light to medium yellow paint. Since that time, synchrotron radiation-based techniques including elemental and spectroscopic imaging, as well as X-ray scattering have been employed to locate and identify the alteration products observed in this and related works by Henri Matisse. This information is necessary to formulate one or multiple mechanisms for degradation of Matisse's paints from this period, and thus ensure proper environmental conditions for the storage and the display of his works. This paper focuses on 2D full-field X-ray Near Edge Structure imaging, 2D micro-X-ray Diffraction, X-ray Fluorescence, and Fourier Transform Infra-red imaging of the altered paint layers to address one of the long-standing questions about cadmium yellow alteration-the roles of cadmium carbonates and cadmium sulphates found in the altered paint layers. These compounds have often been assumed to be photo-oxidation products, but could also be residual starting reagents from an indirect wet process synthesis of CdS. The data presented here allow identifying and mapping the location of cadmium carbonates, cadmium chlorides, cadmium oxalates, cadmium sulphates, and cadmium sulphides in thin sections of altered cadmium yellow paints from The Joy of Life and Matisse's Flower Piece (1906, The Barnes Foundation). Distribution of various cadmium compounds confirms that cadmium carbonates and sulphates are photo-degradation products in The Joy of Life, whereas in Flower Piece, cadmium carbonates appear to have been a [(partially) unreacted] starting reagent for the yellow paint, a role previously suggested in other altered yellow paints.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000364914100017 Publication Date 2015-06-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396; 1432-0630 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:130290 Serial 7382
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Author Trentelman, K.; Janssens, K.; van der Snickt, G.; Szafran, Y.; Woollett, A.T.; Dik, J.
Title Rembrandt's An Old Man in Military Costume: the underlying image re-examined Type A1 Journal article
Year 2015 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
Volume 121 Issue 3 Pages 801-811
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The painting An Old Man in Military Costume in the J. Paul Getty Museum, by Rembrandt Harmensz van Rijn, was studied using two complementary, element-specific imaging techniques-neutron activation autoradiography (NAAR) and macro-X-ray fluorescence (MA-XRF) mapping-to reveal the second, hidden painting. NAAR provided a strong image of the face and cloak of the underlying figure, along with an indication of the chemical composition. The single-element distribution maps produced by MA-XRF mapping provided additional details into the shape of the underlying image and the composition of the pigments used. The underlying figure's face is richer in mercury, indicative of the pigment vermilion, than the face of the figure on the surface. Likewise, the cloak of the underlying figure is richer in copper than the surface figure though the identity of the copper-containing pigment cannot be determined from these data. The use of iron earth pigments, specifically Si-rich umbers, is indicated through the complementary information provided by the NAAR and MA-XRF maps. These data are used to create a false color digital reconstruction, yielding the most detailed representation of the underlying painting to date.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000364914100003 Publication Date 2015-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.455 Times cited 22 Open Access
Notes ; The authors gratefully acknowledge the assistance of all those who aided in the examination of this painting over the decades, that has culminated in the work presented here. Particular thanks go to Mark Leonard (former head of Paintings Conservation at the J. Paul Getty Museum) and Henry Prask (NIST) for carrying out the NAAR analysis; John Twilley (former GCI Scientist) for early investigations; Andrea Sartorius (former JPGM Paintings intern) for creating a mock-up painting used in earlier phases of this work; Peter Reishig (former GCI intern) for compiling the NAAR data; Catherine Patterson, Lynn Lee, and David Carson (GCI Science) and Gene Karraker (JPGM Paintings Conservation) for helping with the setup and operation of the M6 Jetstream; and Giacomo Chiari (former head of GCI Science) for performing the XRD analysis. Koen Janssens and Geert van der Snickt acknowledge the Fund Inbev-Baillet Latour for financial support. Joris Dik acknowledges the help of the Netherlands Organization for Scientific Research (NWO) in the form of a VIDI grant in the Innovational Research Incentive Scheme. ; Approved Most recent IF: 1.455; 2015 IF: 1.704
Call Number UA @ admin @ c:irua:130289 Serial 5812
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Author Kang, J.; Horzum, S.; Peeters, F.M.
Title Heterostructures of graphene and nitrogenated holey graphene: Moire pattern and Dirac ring Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 195419
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Nitrogenated holey graphene (NHG) is a recently synthesized two-dimensional material. In this paper the structural and electronic properties of heterostructures of graphene and NHG are investigated using first-principles and tight-binding calculations. Due to the lattice mismatch between NHG and graphene, the formation of a moire pattern is preferred in the graphene/NHG heterostructure, instead of a lattice-coherent structure. In moire-patterned graphene/NHG, the band gap opening at the K point is negligible, and the linear band dispersion of graphene survives. Applying an electric field modifies the coupling strength between the two atomic layers. The Fermi velocity upsilon(F) is reduced as compared to the one of pristine graphene, and its magnitude depends on the twist angle theta between graphene and NHG: For theta = 0 degrees, upsilon(F) is 30% of that of graphene, and it increases rapidly to a value of 80% with increasing theta. The heterostructure exhibits electron-hole asymmetry in upsilon(F), which is large for small theta. In NHG encapsulated between two graphene layers, a “Dirac ring” appears around the K point. Its presence is robust with respect to the relative stacking of the two graphene layers. These findings can be useful for future applications of graphene/NHG heterostructures.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000364998000006 Publication Date 2015-11-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 33 Open Access
Notes Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:130266 Serial 4189
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Author Missault, N.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.; Van Duppen, B.
Title Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 195423
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study ballistic transport of Dirac fermions in silicene through arrays of barriers, of width d, in the presence of an exchange field M and a tunable potential of height U or depth-U. The spin-and valley-resolved conductances as functions of U or M, exhibit resonances away from the Dirac point (DP) and close to it a pronounced dip that becomes a gap when a critical electric field E-z is applied. This gap widens by increasing the number of barriers and can be used to realize electric field-controlled switching of the current. The spin p(s) and valley p(v) polarizations of the current near the DP increase with Ez or M and can reach 100% for certain of their values. These field ranges widen significantly by increasing the number of barriers. Also, ps and pv oscillate nearly periodically with the separation between barriers or wells and can be inverted by reversing M.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000364998100006 Publication Date 2015-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 54 Open Access
Notes ; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.) and by the Flemish Science Foundation (FWO-Vl) with a Ph.D. research grant (B.V.D.). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:130264 Serial 4247
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Author Van Aelst, J.; Verboekend, D.; Philippaerts, A.; Nuttens, N.; Kurttepeli, M.; Gobechiya, E.; Haouas, M.; Sree, S.P.; Denayer, J.F.M.; Martens, J.A.; Kirschhock, C.E.A.; Taulelle, F.; Bals, S.; Baron, G.V.; Jacobs, P.A.; Sels, B.F.
Title Catalyst design by NH4OH treatment of USY zeolite Type A1 Journal article
Year 2015 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 25 Issue 25 Pages 7130-7144
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Hierarchical zeolites are a class of superior catalysts which couples the intrinsic zeolitic properties to enhanced accessibility and intracrystalline mass transport to and from the active sites. The design of hierarchical USY (Ultra-Stable Y) catalysts is achieved using a sustainable postsynthetic room temperature treatment with mildly alkaline NH4OH ( 0.02(M)) solutions. Starting from a commercial dealuminated USY zeolite (Si/Al = 47), a hierarchical material is obtained by selective and tuneable creation of interconnected and accessible small mesopores (2- 6 nm). In addition, the treatment immediately yields the NH4+ form without the need for additional ion exchange. After NH4OH modification, the crystal morphology is retained, whereas the microporosity and relative crystallinity are decreased. The gradual formation of dense amorphous phases throughout the crystal without significant framework atom leaching rationalizes the very high material yields (>90%). The superior catalytic performance of the developed hierarchical zeolites is demonstrated in the acid-catalyzed isomerization of alpha-pinene and the metal-catalyzed conjugation of safflower oil. Significant improvements in activity and selectivity are attained, as well as a lowered susceptibility to deactivation. The catalytic performance is intimately related to the introduced mesopores, hence enhanced mass transport capacity, and the retained intrinsic zeolitic properties.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000366503700003 Publication Date 2015-10-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 64 Open Access OpenAccess
Notes ; The authors thank Dr. M. Thommes and Dr. K. Cychosz for numerous and helpful discussions on the correct evaluation of the Ar isotherms. I. Cuppens is acknowledged for ICP-AES analyses. Research was funded through a PhD grant to J.V.A. of the Agency for Innovation by Science and Technology in Flanders (IWT). D.V. and A.P. acknowledge F.W.O.-Vlaanderen (Research Foundation Flanders) for a postdoctoral fellowship. N.N. thanks the KU Leuven for financial support (FLOF). E.G., C.K., and J.M. acknowledge the long-term structural funding by the Flemish Government (Methusalem). S.B. acknowledges the European Research Council for funding under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement No. 335078-COLOURATOMS. The authors are grateful for financial support by the Belgian government through Interuniversity Attraction Poles (IAP-PAI). They also thank Oleon NV for supplying safflower oil. ; ecas_Sara Approved Most recent IF: 12.124; 2015 IF: 11.805
Call Number UA @ lucian @ c:irua:130214 Serial 4147
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Author Dell'Anna, L.; Perali, A.; Covaci, L.; Neilson, D.
Title Using magnetic stripes to stabilize superfluidity in electron-hole double monolayer graphene Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 220502
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Experiments have confirmed that double monolayer graphene does not generate finite-temperature electron-hole superfluidity, because of very strong screening of the pairing attraction. The linear dispersing energy bands in monolayer graphene block any attempt to reduce the strength of the screening. We propose a hybrid device with two sheets of monolayer graphene in a modulated periodic perpendicular magnetic field. The field preserves the isotropic Dirac cones of the original monolayers but reduces the slope of the cones, making the monolayer Fermi velocity v(F) smaller. We demonstrate that with current experimental techniques, the reduction in vF can weaken the screening sufficiently to allow electron-hole superfluidity at measurable temperatures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000366500100004 Publication Date 2015-12-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 7 Open Access
Notes ; We thank M. Zarenia for useful discussions. L.D. acknowledges financial support from MIUR: FIRB 2012, Grant No. RBFR12NLNA_002, and PRIN, Grant No. 2010LLKJBX. A.P. and D.N. acknowledge financial support from University of Camerino FAR project CESEMN. L.C. acknowledges financial support from Flemish Science Foundation (FWO). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:130211 Serial 4069
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Author Sobrino Fernandez, M.M.; Neek-Amal, M.; Peeters, F.M.
Title AA-stacked bilayer square ice between graphene layers Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 245428
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Water confined between two graphene layers with a separation of a few A forms a layered two-dimensional ice structure. Using large scale molecular dynamics simulations with the adoptable ReaxFF interatomic potential we found that flat monolayer ice with a rhombic-square structure nucleates between the graphene layers which is nonpolar and nonferroelectric. We provide different energetic considerations and H-bonding results that explain the interlayer and intralayer properties of two-dimensional ice. The controversial AA stacking found experimentally [Algara-Siller et al., Nature (London) 519, 443 (2015)] is consistent with our minimum-energy crystal structure of bilayer ice. Furthermore, we predict that an odd number of layers of ice has the same lattice structure as monolayer ice, while an even number of ice layers exhibits the square ice AA stacking of bilayer ice.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000366731800004 Publication Date 2015-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 40 Open Access
Notes ; This work was supported by the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:130203 Serial 4127
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Author Muguerra, H.; Pescheux, A.-C.; Meledin, A.; Van Tendeloo, G.; Soubeyroux, J.-L.
Title A La2−xGdxZr2O7layer deposited by chemical solution: a promising seed layer for the fabrication of high Jcand low cost coated conductors Type A1 Journal article
Year 2015 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
Volume 3 Issue 3 Pages 11766-11772
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We deposited La2-xGdxZr2O7 seed layers by a chemical solution method on a Ni-5%W substrate to study the influence of these layers on the growth process of a 60 nm-thick La2Zr2O7 layer. We measured the performances of these new buffer layers integrated in a coated conductor with a 300 nm-thick Y0.5Gd0.5Ba2Cu3O7-x layer. For the seed layers{,} we considered two different gadolinium contents (x = 0.2 and x = 0.8) and three different thicknesses for these compositions (20 nm{,} 40 nm{,} and 60 nm). The most promising buffer layer stacks are those with 20 nm of the La1.8Gd0.2Zr2O7 layer or La1.2Gd0.8Zr2O7. Indeed the La2-xGdxZr2O7/La2Zr2O7 films are highly textured{,} similar to a 100 nm-thick La2Zr2O7 layer{,} but their roughness is four times lower. Moreover they contain less and smaller pores in the seed layer than a pure La2Zr2O7 layer. The surface of La2Zr2O7 is also homogenous and crystalline with an orientation deviation from the ideal ?011? (100) direction below 10[degree]. With the 20 nm La2-xGdxZr2O7 seed layers we obtain in the coated conductors an efficiently textured transfer with no gradual degradation from the substrate throughout the superconducting layer. The highest Tc and Jc values are achieved with the La1.8Gd0.2Zr2O7 layer and are{,} respectively{,} 91 K and 1.4 MA cm-2. This trend seems to be due to an improvement of the surface quality of the Ni5%W substrate by the addition of a thin seed layer. Our results offer the potential of the La2-xGdxZr2O7 seed layers as promising alternatives for the classic Ni-5%W/LZO/CeO2/YBCO architectures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000364826000024 Publication Date 2015-10-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526;2050-7534; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 5.256 Times cited 4 Open Access
Notes This work was performed within the framework of the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280438), funded by the European Union. The authors also thank L. Porcar and P. Chometon for superconducting transition temperature and critical current density measurements and P. Odier for fruitful discussion. Approved Most recent IF: 5.256; 2015 IF: 4.696
Call Number c:irua:130181 Serial 3968
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Author Yan, L.; Tan, Z.; Ji, G.; Li, Z.; Fan, G.; Schryvers, D.; Shan, A.; Zhang, D.
Title A quantitative method to characterize the Al4C3-formed interfacial reaction: the case study of MWCNT/Al composites Type A1 Journal article
Year 2015 Publication Materials characterization Abbreviated Journal Mater Charact
Volume 112 Issue 112 Pages 213-218
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The Al4C3-formed interfacial reaction plays an important role in tuning the mechanical and thermal properties of carbon/aluminum (C/Al) composites reinforced with carbonaceous materials such as multi-wall carbon nanotube (MWCNT) and graphene nanosheet. In terms of the hydrolysis nature of Al4C3, an electrochemical dissolution method was developed to quantitatively characterize the extent of C/Al interfacial reaction, which involves dissolving the composite samples in alkaline solution first, then collecting and measuring the CH4 gas released by Al4C3 hydrolysis with a gas chromatograph. Through a case study with powder metallurgy fabricated 2.0 wt.% MWCNT/Al composites, the detectability limit of the proposed method is 0.4 wt.% Al4C3, corresponding to 5 % extent of interfacial reaction with a measurement error of ±3 %. And then, with the already known MWCNT/Al reaction extent vs different sintering temperature and time, the reaction kinetics with an activation energy of 281 kJ mol-1 was successfully derived. Therefore, this rapid, sensitive, accurate method supplies an useful tool to optimize the processing and properties of all kinds of C/Al composites via interface design/control.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000370109200026 Publication Date 2015-12-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.714 Times cited 24 Open Access
Notes The authors would like to acknowledge the financial support of the National Basic Research Program of China (973 Program, No. 2012CB619600), the National High-Tech R&D Program (863 Program, No. 2012AA030611), the National Natural Science Foundation (Nos. 51071100, 51131004, 51401123, 51511130038) and the research grant (Nos. 14DZ2261200, 15JC1402100, 14520710100) from Shanghai government. Dr. Z.Q. Tan would also like to thank the project funded by the China Postdoctoral Science Foundation (No. 2014M561469). The research leading to these results has partially received funding from the European Union Seventh Framework Program under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative – I3).; esteem2_jra2 Approved Most recent IF: 2.714; 2015 IF: 1.845
Call Number c:irua:130066 c:irua:130066 Serial 3997
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Author Poelma, R.H.; Fan, X.; Hu, Z.-Y.; Van Tendeloo, G.; van Zeijl, H.W.; Zhang, G.Q.
Title Effects of Nanostructure and Coating on the Mechanics of Carbon Nanotube Arrays Type A1 Journal article
Year 2016 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 26 Issue 26 Pages 1233-1242
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanoscale materials are one of the few engineering materials that can be grown from the bottom up in a controlled manner. Here, the effects of nanostructure and nanoscale conformal coating on the mechanical behavior of vertically aligned carbon nanotube (CNT) arrays through experiments and simulation are systematically investigated. A modeling approach is developed and used to quantify the compressive strength and modulus of the CNT array under large deformation. The model accounts for the porous

nanostructure, which contains multiple CNTs with random waviness, van der Waals interactions, fracture strain, contacts, and frictional forces. CNT array micropillars are grown and their porous nanostructure is controlled by the infi ltration and deposition of thin conformal coatings using chemical vapor deposition. Flat-punch nanoindentation experiments reveal signifi cant changes in material properties as a function of coating thickness. The simulations explain the experimental results and show the novel failure transition regime that changes from collective CNT buckling toward structural collapse due to fracture. The compressive strength and the elastic

modulus increase exponentially as a function of the coating thickness and demonstrate a unique dependency on the CNT waviness. More interestingly, a design rule is identifi ed that predicts the optimum coating thickness for porous materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000371078100010 Publication Date 2016-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301X ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 17 Open Access
Notes The research leading to the TEM/HAADF-STEM results received funding from the EC Framework 7 Program ESTEEM2 (Reference 312483). We wish to acknowledge the support of the Else Kooi Laboratory for their assistance during the clean room processing.; esteem2_ta Approved Most recent IF: 12.124
Call Number c:irua:130060 c:irua:130060 Serial 3996
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Author Yao, X.; Cao, S.; Zhang, X.P.; Schryvers, D.
Title Microstructural Characterization and Transformation Behavior of Porous Ni50.8Ti49.2 Type P1 Proceeding
Year 2015 Publication Materials Today: Proceedings Abbreviated Journal
Volume 2 Issue 2 Pages S833-S836
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract Porous Ni50.8Ti49.2 bulk material was prepared by powder metallurgy sintering. Solid solution and aging treatments were applied to improve the phase homogeneity and phase transformation behavior. Scanning and transmission electron microscopy, aided by energy dispersive X-ray analysis, were used to study the microstructure and chemical phase content of the alloys. In-situ cooling was carried out to observe the phase transformation behavior. As-received material contains dispersed Ni2Ti4O particles while Ni4Ti3 precipitates appear after aging. Close to pore edges, the latter have a preferential orientation due to the induced stress fields in the matrix.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000371032100081 Publication Date 2015-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2214-7853 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes The author gratefully acknowledges the Chinese Scholarship Council (CSC) for providing a scholarship and the Key Project of the Natural Science Foundation of Guangdong Province under grant No. S2013020012805. Approved Most recent IF: NA
Call Number c:irua:129980 Serial 3989
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Author Ji, G.; Tan, Z.; Lu, Y.; Schryvers, D.; Li, Z.; Zhang, D.
Title Heterogeneous interfacial chemical nature and bonds in a W-coated diamond/Al composite Type A1 Journal article
Year 2016 Publication Materials characterization Abbreviated Journal Mater Charact
Volume 112 Issue 112 Pages 129-133
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Heterogeneous Al/Al4C3/Al2O3/diamond{111}, Al/nanolayered Al4C3/diamond{111} and Al12W particle/Al4C3/Al2O3/diamond{111} multi-interfaces have been developed at the nanoscale in a W-coated diamond/Al composite produced by vacuum hot pressing. The formation of nanoscale Al4C3 crystals is strongly associated with local O enrichment and can be further promoted by Al12W interfacial particles. The latter effectively contributes to enhance interfacial chemical bonding reducing interfacial thermal resistance and, in turn, enhancing thermal conductivity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000370109200015 Publication Date 2015-12-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.714 Times cited 7 Open Access
Notes This work is financially supported by the FWO project of Belgium (No. U2 FA 070100/3506), the travel funding BQR (No. R8DIV AUE) provided by Université Lille 1, the National Natural Science Foundation of China (Grant No. 51401123) and the China Postdoctoral Science Foundation (Grant No. 2014 M561469) for Dr. Z.Q. Tan. Dr. W.G. Grünewald (LeicaMicrosystems, Germany) is also thanked for the assistance of surface preparation. Approved Most recent IF: 2.714
Call Number c:irua:129976 Serial 3987
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Author Wang, Y.; Sentosun, K.; Li, A.; Coronado-Puchau, M.; Sánchez-Iglesias, A.; Li, S.; Su, X.; Bals, S.; Liz-Marzán, L.M.
Title Engineering Structural Diversity in Gold Nanocrystals by Ligand-Mediated Interface Control Type A1 Journal article
Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 27 Issue 27 Pages 8032-8040
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Surface and interface control is fundamentally important for crystal growth engineering, catalysis, surface enhanced spectroscopies, and self-assembly, among other processes and applications. Understanding the role of ligands in regulating surface properties of plasmonic metal nanocrystals during growth has received considerable attention. However, the underlying mechanisms and the diverse functionalities of ligands are yet to be fully addressed. In this contribution,

we report a systematic study of ligand-mediated interface control in seeded growth of gold nanocrystals, leading to diverse and exotic nanostructures with an improved surface enhanced Raman scattering (SERS) activity. Three dimensional transmission electron microscopy (3D TEM) revealed an intriguing gold shell growth process mediated by the bifunctional ligand 1,4-benzenedithiol (BDT), which leads to a unique crystal growth mechanism as compared to other ligands, and subsequently to the concept of interfacial energy control mechanism. Volmer-Weber growth mode was proposed to be responsible for BDT-mediated seeded growth, favoring the strongest interfacial energy and generating an asymmetric island growth pathway with internal crevices/gaps. This additionally favors incorporation of BDT at the plasmonic nanogaps, thereby generating strong SERS activity with a maximum efficiency for a core-semishell configuration obtained along seeded growth. Numerical modeling was used to explain this observation. Interestingly, the same strategy can be used to engineer the structural diversity of this system, by using gold nanoparticle seeds with various sizes and shapes, and varying the [Au3+]/[Au0] ratio. This rendered a series of diverse and exotic plasmonic nanohybrids such as semishell-coated gold nanorods, with embedded Raman-active tags and Janus surface with distinct surface functionalities.

These would greatly enrich the plasmonic nanostructure toolbox for various studies and applications such as anisotropic nanocrystal engineering, SERS, and high-resolution Raman bioimaging or nanoantenna devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000366223200023 Publication Date 2015-10-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 18 Open Access OpenAccess
Notes The authors thank Bart Goris for his help with electron tomography. This work was funded by the European Commission (Grant #310445-2, SAVVY). The authors acknowledge financial support from European Research Council (ERC Advanced Grant # 267867- PLASMAQUO, ERC Starting Grant #335078-COLOURATOMS). The authors also appreciate financial support from the European Union under the Seventh Framework Program (Integrated Infrastructure Initiative N. 262348 European Soft Matter Infrastructure, ESMI). Wang Y. and Su X. would like to acknowledge the Agency for Science, Technology and Research (A*STAR), Singapore, for the financial support under the Grant JCO 14302FG096. M. C.-P. acknowledges an FPU scholarship from the Spanish Ministry of Education, Culture and Sports.; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 9.466; 2015 IF: 8.354
Call Number c:irua:129598 c:irua:129598 Serial 3972
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Author Zalfani, M.; van der Schueren, B.; Hu, Z.-Y.; Rooke, J.C.; Bourguiga, R.; Wu, M.; Li, Y.; Van Tendeloo, G.; Su, B.-L.
Title Novel 3DOM BiVO4/TiO2nanocomposites for highly enhanced photocatalytic activity Type A1 Journal article
Year 2015 Publication Journal of materials chemistry A : materials for energy and sustainability Abbreviated Journal J Mater Chem A
Volume 3 Issue 3 Pages 21244-21256
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Novel 3DOM BiVO4/TiO2 nanocomposites with intimate contact were for the first time synthesized by a hydrothermal method in order to elucidate their visible-light-driven photocatalytic performances. BiVO4 nanoparticles and 3DOM TiO2 inverse opal were fabricated respectively. These materials were characterized by XRD, XPS, SEM, TEM, N2 adsorption–desorption and UV-vis diffuse (UV-vis) and photoluminescence spectroscopies. As references for comparison, a physical mixture of BiVO4 nanoparticles and 3DOM TiO2 inverse opal powder (0.08 : 1), and a BiVO4/P25 TiO2 (0.08 : 1) nanocomposite made also by the hydrothermal method were prepared. The photocatalytic performance of all the prepared materials was evaluated by the degradation of rhodamine B (RhB) as a model pollutant molecule under visible light irradiation. The highly ordered 3D macroporous inverse opal structure can provide more active surface areas and increased mass transfer because of its highly accessible 3D porosity. The results show that 3DOM BiVO4/TiO2 nanocomposites possess a highly prolonged lifetime and increased separation of visible light generated charges and extraordinarily high photocatalytic activity. Owing to the intimate contact between BiVO4 and large surface area 3DOM TiO2, the photogenerated high energy charges can be easily transferred from BiVO4 to the 3DOM TiO2 support. BiVO4 nanoparticles in the 3DOM TiO2 inverse opal structure act thus as a sensitizer to absorb visible light and to transfer efficiently high energy electrons to TiO2 to ensure long lifetime of the photogenerated charges and keep them well separated, owing to the direct band gap of BiVO4 of 2.4 eV, favourably positioned band edges, very low recombination rate of electron–hole pairs and stability when coupled with photocatalysts, explaining the extraordinarily high photocatalytic performance of 3DOM BiVO4/TiO2 nanocomposites. It is found that larger the amount of BiVO4 in the nanocomposite, longer the duration of photogenerated charge separation and higher the photocatalytic activity. This work can shed light on the development of novel visible light responsive nanomaterials for efficient solar energy utilisation by the intimate combination of an inorganic light sensitizing nanoparticle with an inverse opal structure with high diffusion efficiency and high accessible surface area.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000363163200049 Publication Date 2015-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7488;2050-7496; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 8.867 Times cited 88 Open Access
Notes This work was realized with the financial support of the Belgian FNRS (Fonds National de la Recherche Scientifique). This research used resources of the Electron Microscopy Service located at the University of Namur. This Service is a member of the “Plateforme Technologique Morphologie – Imagerie”. The XPS analyses were made in the LISE, Department of Physics of the University of Namur thanks to Dr P. Louette. This work was also supported by Changjiang Scholars and the Innovative Research Team (IRT1169) of the Ministry of Education of the People's Republic of China. B. L. Su acknowledges the Chinese Central Government for an “Expert of the State” position in the Program of the “Thousand Talents” and a Clare Hall Life Membership at the Clare Hall and the financial support of the Department of Chemistry, University of Cambridge. G. Van Tendeloo and Z. Y. Hu acknowledge support from the EC Framework 7 program ESTEEM2 (Reference 312483).; esteem2_jra4 Approved Most recent IF: 8.867; 2015 IF: 7.443
Call Number c:irua:129476 c:irua:129476 Serial 3951
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Author Neek-Amal, M; Peeters, F.M.
Title Partially hydrogenated and fluorinated graphene : structure, roughness, and negative thermal expansion Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 155430
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The structural properties of partially hydrogenated and fluorinated graphene with different percentages of H/F atoms are investigated using molecular dynamics simulations based on reactive force field (ReaxFF) potentials. We found that the roughness of graphene varies with the percentage (p) of H or F and in both cases is maximal around p = 50%. Similar results were obtained for partially oxidized graphene. The two-dimensional area size of partially fluorinated and hydrogenated graphene exhibits a local minimum around p = 35% coverage. The lattice thermal contraction in partially functionalized graphene is found to be one order of magnitude larger than that of fully covered graphene. We also show that the armchair structure for graphene oxide (similar to the structure of fully hydrogenated and fluorinated graphene) is unstable. Our results show that the structure of partially functionalized graphene changes nontrivially with the C : H and C : F ratio as well as with temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000363294100005 Publication Date 2015-10-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 5 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:129448 Serial 4221
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Author Alyörük, M.M.; Aierken, Y.; Çakır, D.; Peeters, F.M.; Sevik, C.
Title Promising Piezoelectric Performance of Single Layer Transition-Metal Dichalcogenides and Dioxides Type A1 Journal article
Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 119 Issue 119 Pages 23231-23237
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Piezoelectricity is a unique material property that allows one to convert mechanical energy into electrical one or vice versa. Transition metal dichalcogenides (TMDC) and transition metal dioxides (TMDO) are expected to have great potential for piezoelectric device applications due to their noncentrosymmetric and two-dimensional crystal structure. A detailed theoretical investigation of the piezoelectric stress (e 11 ) and piezoelectric strain (d 11 ) coefficients of single layer TMDCs and TMDOs with chemical formula MX 2 (where M= Cr, Mo, W, Ti, Zr, Hf, Sn and X = O, S, Se, Te) is presented by using first-principles calculations based on density func- tional theory. We predict that not only the Mo- and W-based members of this family but also the other materials with M= Cr, Ti, Zr and Sn exhibit highly promising piezoelectric properties. CrTe 2 has the largest e 11 and d 11 coefficients among the group VI elements (i.e., Cr, Mo, and W). In addition, the relaxed-ion e 11 and d 11 coefficients of SnS 2 are almost the same as those of CrTe 2 . Furthermore, TiO 2 and ZrO 2 pose comparable or even larger e 11 coefficients as compared to Mo- and W-based TMDCs and TMDOs. Our calculations reveal that TMDC and TMDO structures are strong candidates for future atomically thin piezoelectric applications such as transducers, sensors, and energy harvesting devices due to their piezoelectric coefficients that are comparable (even larger) to currently used bulk piezoelectric materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000362702100054 Publication Date 2015-09-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 134 Open Access
Notes M.M.A and C.S. acknowledges the support from Scientific and Technological Research Council of Turkey (TUBITAK- 113F333). C.S. acknowledges support from Anadolu University (BAP-1407F335, -1505F200), and Turkish Academy of Sciences (TUBA-GEBIP). 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. Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:129418 Serial 4035
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Author Juchtmans, R.; Verbeeck, J.
Title Orbital angular momentum in electron diffraction and its use to determine chiral crystal symmetries Type A1 Journal article
Year 2015 Publication Physical review: B: condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 134108
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this work we present an alternative way to look at electron diffraction in a transmission electron microscope.

Instead of writing the scattering amplitude in Fourier space as a set of plane waves,we use the cylindrical Fourier transform to describe the scattering amplitude in a basis of orbital angular momentum (OAM) eigenstates. We show how working in this framework can be very convenient when investigating, e.g., rotation and screw-axis symmetries. For the latter we find selection rules on the OAM coefficients that unambiguously reveal the handedness of the screw axis. Detecting the OAM coefficients of the scattering amplitude thus offers the possibility to detect the handedness of crystals without the need for dynamical simulations, the thickness of the sample, nor the exact crystal structure. We propose an experimental setup to measure the OAM components where an image of the crystal is taken after inserting a spiral phase plate in the diffraction plane and perform multislice simulations on α quartz to demonstrate how the method indeed reveals the chirality. The experimental feasibility of the technique is discussed together with its main advantages with respect to chirality determination of screw axes. The method shows how the use of a spiral phase plate can be extended from a simple phase imaging technique to a tool to measure the local OAM decomposition of an electron wave, widening the field of interest well beyond chiral space group determination.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000362893100002 Publication Date 2015-10-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 16 Open Access
Notes The authors acknowledge support from the FWO (As- pirant Fonds Wetenschappelijk Onderzoek–Vlaanderen), the EU under the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2, and ERC Starting Grant No. 278510 VORTEX; esteem2jra1; ECASJO; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:129417 c:irua:129417UA @ admin @ c:irua:129417 Serial 4089
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Author Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Kaunisto, K.; Sada, C.; Turner, S.; Gönüllü, Y.; Ruoko, T.-P.; Borgese, L.; Bontempi, E.; Van Tendeloo, G.; Lemmetyinen, H.; Mathur, S.
Title Fe2O3-TiO2Nano-heterostructure Photoanodes for Highly Efficient Solar Water Oxidation Type A1 Journal article
Year 2015 Publication Advanced Materials Interfaces Abbreviated Journal Adv Mater Interfaces
Volume 2 Issue 2 Pages 1500313
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Harnessing solar energy for the production of clean hydrogen by photo­electrochemical water splitting represents a very attractive, but challenging approach for sustainable energy generation. In this regard, the fabrication of Fe2O3–TiO2 photoanodes is reported, showing attractive performances [≈2.0 mA cm−2 at 1.23 V vs. the reversible hydrogen electrode in 1 M NaOH] under simulated one-sun illumination. This goal, corresponding to a tenfold photoactivity enhancement with respect to bare Fe2O3, is achieved by atomic layer deposition of TiO2 over hematite (α-Fe2O3) nanostructures fabricated by plasma enhanced-chemical vapor deposition and final annealing at 650 °C. The adopted approach enables an intimate Fe2O3–TiO2 coupling, resulting in an electronic interplay at the Fe2O3/TiO2 interface. The reasons for the photocurrent enhancement determined by TiO2 overlayers with increasing thickness are unraveled by a detailed chemico-physical investigation, as well as by the study of photo­generated charge carrier dynamics. Transient absorption spectroscopy shows that the increased photoelectrochemical response of heterostructured photoanodes compared to bare hematite is due to an enhanced separation of photogenerated charge carriers and more favorable hole dynamics for water oxidation. The stable responses obtained even in simulated seawater provides a feasible route in view of the eventual large-scale generation of renewable energy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368914700011 Publication Date 2015-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2196-7350; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 4.279 Times cited 56 Open Access
Notes The authors kindly acknowledge the fi nancial support under the FP7 project “SOLAROGENIX” (NMP4-SL-2012-310333), as well as Padova University ex-60% 2012–2014 projects, Grant No. CPDR132937/13 (SOLLEONE), and Regione Lombardia-INSTM ATLANTE projects. S.T. acknowledges the FWO Flanders for a postdoctoral scholarship. Approved Most recent IF: 4.279; 2015 IF: NA
Call Number c:irua:129201 Serial 3957
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Author Zeng, Y.-J.; Gauquelin, N.; Li, D.-Y.; Ruan, S.-C.; He, H.-P.; Egoavil, R.; Ye, Z.-Z.; Verbeeck, J.; Hadermann, J.; Van Bael, M.J.; Van Haesendonck, C.
Title Co-Rich ZnCoO Nanoparticles Embedded in Wurtzite Zn1-xCoxO Thin Films: Possible Origin of Superconductivity Type A1 Journal article
Year 2015 Publication ACS applied materials and interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 7 Issue 7 Pages 22166-22171
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Co-rich ZnCoO nanoparticles embedded in wurtzite Zn0.7Co0.3O thin films are grown by pulsed laser deposition on a Si substrate. Local superconductivity with an onset Tc at 5.9 K is demonstrated in the hybrid system. The unexpected superconductivity probably results from Co(3+) in the Co-rich ZnCoO nanoparticles or from the interface between the Co-rich nanoparticles and the Zn0.7Co0.3O matrix.
Address Solid State Physics and Magnetism Section, KU Leuven , Celestijnenlaan 200 D, BE-3001 Leuven, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000363001500007 Publication Date 2015-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244;1944-8252; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited 13 Open Access
Notes This work has been supported by the Research Foundation − Flanders (FWO, Belgium) as well as by the Flemish Concerted Research Action program (BOF KU Leuven, GOA/14/007). N. G. and J. V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Flemish Hercules Foundation. The work at Shenzhen University was supported by National Natural Science Foundation of China under Grant No. 61275144 and Natural Science Foundation of SZU. Y.-J. Z. acknowledges funding under grant No. SKL2015-12 from the State Key Laboratory of Silicon Materials; ECASJO_; Approved Most recent IF: 7.504; 2015 IF: 6.723
Call Number c:irua:129195 c:irua:129195UA @ admin @ c:irua:129195 Serial 3949
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M.
Title Disordered graphene Josephson junctions Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 91 Issue 91 Pages 054506
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A tight-binding approach based on the Chebyshev-Bogoliubov-de Gennes method is used to describe disordered single-layer graphene Josephson junctions. Scattering by vacancies, ripples, or charged impurities is included. We compute the Josephson current and investigate the nature of multiple Andreev reflections, which induce bound states appearing as peaks in the density of states for energies below the superconducting gap. In the presence of single-atom vacancies, we observe a strong suppression of the supercurrent, which is a consequence of strong intervalley scattering. Although lattice deformations should not induce intervalley scattering, we find that the supercurrent is still suppressed, which is due to the presence of pseudomagnetic barriers. For charged impurities, we consider two cases depending on whether the average doping is zero, i.e., existence of electron-hole puddles, or finite. In both cases, short-range impurities strongly affect the supercurrent, similar to the vacancies scenario.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000349436500001 Publication Date 2015-02-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 7 Open Access
Notes This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Methusalem funding of the Flemish Government. Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:129192 Serial 3961
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Author Wolf, D.; Rodriguez, L.A.; Béché, A.; Javon, E.; Serrano, L.; Magen, C.; Gatel, C.; Lubk, A.; Lichte, H.; Bals, S.; Van Tendeloo, G.; Fernández-Pacheco, A.; De Teresa, J.M.; Snoeck, E.
Title 3D Magnetic Induction Maps of Nanoscale Materials Revealed by Electron Holographic Tomography Type A1 Journal article
Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 27 Issue 27 Pages 6771-6778
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The investigation of three-dimensional (3D) ferromagnetic nanoscale materials constitutes one of the key research areas of the current magnetism roadmap, and carries great potential to impact areas such as data storage, sensing and biomagnetism. The properties of such nanostructures are closely connected with their 3D magnetic nanostructure, making their determination highly valuable. Up to now, quantitative 3D maps providing both the internal magnetic and electric configuration of the same specimen with high spatial resolution are missing. Here, we demonstrate the quantitative 3D reconstruction of the dominant axial component of the magnetic induction and electrostatic potential within a cobalt nanowire (NW) of 100 nm in diameter with spatial resolution below 10 nanometers by applying electron holographic tomography. The tomogram was obtained using a dedicated TEM sample holder for acquisition, in combination with advanced alignment and tomographic reconstruction routines. The powerful approach presented here is widely applicable to a broad range of 3D magnetic nanostructures and may trigger the progress of novel spintronic non-planar nanodevices.
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Language Wos 000362920700037 Publication Date 2015-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 50 Open Access OpenAccess
Notes This work was supported by the European Union under the Seventh Framework Program under a contract for an Inte-grated Infrastructure Initiative Reference 312483-ESTEEM2. S.B. and A.B. gratefully acknowledge funding by ERC Starting grants number 335078 COLOURATOMS and number 278510 VORTEX. AF-P acknowledges an EPSRC Early Career fellowship and support from the Winton Foundation. E.S., C.G. and L.A. R. acknowledge the French ANR program for support though the project EMMA.; esteem2jra4; ECASJO;; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 9.466; 2015 IF: 8.354
Call Number c:irua:129180 c:irua:129180 c:irua:129180 Serial 3950
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M.
Title Superconducting current and proximity effect in ABA and ABC multilayer graphene Josephson junctions Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 88 Issue 88 Pages 214502
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using a numerical tight-binding approach based on the Chebyshev–Bogoliubov–de Gennes method we describe Josephson junctions made of multilayer graphene contacted by top superconducting gates. Both Bernal (ABA) and rhombohedral (ABC) stacking are considered and we find that the type of stacking has a strong effect on the proximity effect and the supercurrent flow. For both cases the pair amplitude shows a polarization between dimer and nondimer atoms, being more pronounced for rhombohedral stacking. Even though the proximity effect in nondimer sites is enhanced when compared to single-layer graphene, we find that the supercurrent is suppressed. The spatial distribution of the supercurrent shows that for Bernal stacking the current flows only in the topmost layers while for rhombohedral stacking the current flows throughout the whole structure.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000328569900004 Publication Date 2013-12-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 4 Open Access
Notes This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number CMT @ cmt @ c:irua:128896 Serial 3962
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