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Author Vanherck, J.; Sorée, B.; Magnus, W.
Title Anisotropic bulk and planar Heisenberg ferromagnets in uniform, arbitrarily oriented magnetic fields Type A1 Journal article
Year 2018 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 30 Issue 27 Pages 275801
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Today, further downscaling of mobile electronic devices poses serious problems, such as energy consumption and local heat dissipation. In this context, spin wave majority gates made of very thin ferromagnetic films may offer a viable alternative. However, similar downscaling of magnetic thin films eventually enforces the latter to operate as quasi-2D magnets, the magnetic properties of which are not yet fully understood, especially those related to anisotropies and external magnetic fields in arbitrary directions. To this end, we have investigated the behaviour of an easy-plane and easy-axis anisotropic ferromagnet-both in two and three dimensions-subjected to a uniform magnetic field, applied along an arbitrary direction. In this paper, a spin-1/2 Heisenberg Hamiltonian with anisotropic exchange interactions is solved using double-time temperature-dependent Green's functions and the Tyablikov decoupling approximation. We determine various magnetic properties such as the Curie temperature and the magnetization as a function of temperature and the applied magnetic field, discussing the impact of the system's dimensionality and the type of anisotropy. The magnetic reorientation transition taking place in anisotropic Heisenberg ferromagnets is studied in detail. Importantly, spontaneous magnetization is found to be absent for easy-plane 2D spin systems with short range interactions.
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Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000434980600001 Publication Date 2018-05-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited Open Access
Notes ; ; Approved Most recent IF: 2.649
Call Number (up) UA @ lucian @ c:irua:151945UA @ admin @ c:irua:151945 Serial 5012
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Author Kong, X.; Li, L.; Peeters, F.M.
Title Topological Dirac semimetal phase in <tex> $GexSny alloys Type A1 Journal article
Year 2018 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 112 Issue 25 Pages 251601
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Recently, two stable allotropes (germancite and stancite) for the group IV elements (Ge and Sn) with a staggered layered dumbell structure were proposed to be three-dimensional (3D) topological Dirac semimetals [Phys. Rev. B 93, 241117 (2016)]. A pair of Dirac points is on the rotation axis away from the time-reversal invariant momentum, and the stability of the 3D bulk Dirac points is protected by the C-3 rotation symmetry. Here, we use the first principles calculations to investigate GexSny alloys which share the same rhombohedral crystal structure with the space group of D-3d(6). Six GexSny alloys are predicted to be energetically and dynamically stable, where (x, y) = (8, 6) and (6, 8) and the alpha and beta phases of (10, 4) and (4, 10). Our results demonstrate that all the six GexSny alloys are topological Dirac semimetals. The different nontrivial surface states and surface Fermi arcs are identified. Our work will substantially enrich the family of 3D Dirac semimetals which are within the reach of experimental realization. Published by AIP Publishing.
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Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000435987400013 Publication Date 2018-06-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 8 Open Access
Notes ; This work was supported by the Collaborative Innovation Center of Quantum Matter, the Fonds voor Wetenschappelijk Onderzoek (FWO-VI), and the FLAG-ERA Project TRANS 2D TMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. ; Approved Most recent IF: 3.411
Call Number (up) UA @ lucian @ c:irua:151970UA @ admin @ c:irua:151970 Serial 5045
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Author Grimaud, A.; Iadecola, A.; Batuk, D.; Saubanere, M.; Abakumov, A.M.; Freeland, J.W.; Cabana, J.; Li, H.; Doublet, M.-L.; Rousse, G.; Tarascon, J.-M.
Title Chemical activity of the peroxide/oxide redox couple : case study of Ba5Ru2O11 in aqueous and organic solvents Type A1 Journal article
Year 2018 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 30 Issue 11 Pages 3882-3893
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The finding that triggering the redox activity of oxygen ions within the lattice of transition metal oxides can boost the performances of materials used in energy storage and conversion devices such as Li-ion batteries or oxygen evolution electrocatalysts has recently spurred intensive and innovative research in the field of energy. While experimental and theoretical efforts have been critical in understanding the role of oxygen nonbonding states in the redox activity of oxygen ions, a clear picture of the redox chemistry of the oxygen species formed upon this oxidation process is still missing. This can be, in part, explained by the complexity in stabilizing and studying these species once electrochemically formed. In this work, we alleviate this difficulty by studying the phase Ba5Ru2O11, which contains peroxide O-2(2-) groups, as oxygen evolution reaction electrocatalyst and Li-ion battery material. Combining physical characterization and electrochemical measurements, we demonstrate that peroxide groups can easily be oxidized at relatively low potential, leading to the formation of gaseous dioxygen and to the instability of the oxide. Furthermore, we demonstrate that, owing to the stabilization at high energy of peroxide, the high-lying energy of the empty sigma* antibonding O-O states limits the reversibility of the electrochemical reactions when the O-2(2-)/O2- redox couple is used as redox center for Li-ion battery materials or as OER redox active sites. Overall, this work suggests that the formation of true peroxide O-2(2-) states are detrimental for transition metal oxides used as OER catalysts and Li-ion battery materials. Rather, oxygen species with O-O bond order lower than 1 would be preferred for these applications.
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Publisher American Chemical Society Place of Publication Washington, D.C Editor
Language Wos 000435416600038 Publication Date 2018-05-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 2 Open Access Not_Open_Access
Notes ; We thank S. Belin of the ROCK beamline (financed by the French National Research Agency (ANR) as a part of the “Investissements d'Avenir” program, reference: ANR-10-EQPX-45; proposal no. 20160095) of synchrotron SOLEIL for her assistance during XAS measurements. Authors would also like to thank V. Nassif for her assistance on the D1B beamline. A.G, G.R, and J.-M.T. acknowledge funding from the European Research Council (ERC) (FP/2014)/ERC Grant Project 670116-ARPEMA. ; Approved Most recent IF: 9.466
Call Number (up) UA @ lucian @ c:irua:151980 Serial 5016
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Author Chen, Q.; Wang, W.; Peeters, F.M.
Title Magneto-polarons in monolayer transition-metal dichalcogenides Type A1 Journal article
Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 123 Issue 21 Pages 214303
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Landau levels (LLs) are modified by the Frohlich interaction which we investigate within the improved Wigner-Brillouin theory for energies both below and above the longitudinal-optical-continuum in monolayer MoS2.., WS2, MoSe2, and WSe2. Polaron corrections to the LLs are enhanced in monolayer MoS2 as compared to WS2. A series of levels are found at h omega(LO) + lh omega(c), and in addition, the Frohlich interaction lifts the degeneracy between the levels nh omega(c) and h omega(LO) + lh omega(c) resulting in an anticrossing. The screening effect due to the environment plays an important role in the polaron energy corrections, which are also affected by the effective thickness r(eff) parameter. The polaron anticrossing energy gap E-gap decreases with increasing effective thickness r(eff). Published by AIP Publishing.
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Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000434775500014 Publication Date 2018-06-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 19 Open Access
Notes ; Q. Chen and W. Wang acknowledge the financial support from the China Scholarship Council (CSC). This work was also supported by Hunan Provincial Natural Science Foundation of China (Grant No. 2015JJ2040), by the Scientific Research Fund of Hunan Provincial Education Department (Grant No. 15A042), and by the National Natural Science Foundation of China (Grant No. 11404214). ; Approved Most recent IF: 2.068
Call Number (up) UA @ lucian @ c:irua:151985UA @ admin @ c:irua:151985 Serial 5031
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Author Hu, S.; Gopinadhan, K.; Rakowski, A.; Neek-Amal, M.; Heine, T.; Grigorieva, I.V.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M.
Title Transport of hydrogen isotopes through interlayer spacing in van der Waals crystals Type A1 Journal article
Year 2018 Publication Nature nanotechnology Abbreviated Journal Nat Nanotechnol
Volume 13 Issue 6 Pages 468-+
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Atoms start behaving as waves rather than classical particles if confined in spaces commensurate with their de Broglie wavelength. At room temperature this length is only about one angstrom even for the lightest atom, hydrogen. This restricts quantum-confinement phenomena for atomic species to the realm of very low temperatures(1-5). Here, we show that van der Waals gaps between atomic planes of layered crystals provide angstrom-size channels that make quantum confinement of protons apparent even at room temperature. Our transport measurements show that thermal protons experience a notably higher barrier than deuterons when entering van der Waals gaps in hexagonal boron nitride and molybdenum disulfide. This is attributed to the difference in the de Broglie wavelengths of the isotopes. Once inside the crystals, transport of both isotopes can be described by classical diffusion, albeit with unexpectedly fast rates comparable to that of protons in water. The demonstrated angstrom-size channels can be exploited for further studies of atomistic quantum confinement and, if the technology can be scaled up, for sieving hydrogen isotopes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000434715700015 Publication Date 2018-04-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-3387; 1748-3395 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 38.986 Times cited 32 Open Access
Notes ; The authors acknowledge support from the Lloyd's Register Foundation, EPSRC – EP/N010345/1, the European Research Council ARTIMATTER project – ERC-2012-ADG and from Graphene Flagship. M.L.-H. acknowledges a Leverhulme Early Career Fellowship. ; Approved Most recent IF: 38.986
Call Number (up) UA @ lucian @ c:irua:152014UA @ admin @ c:irua:152014 Serial 5046
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Author Van Pottelberge, R.; Zarenia, M.; Peeters, F.M.
Title Comment on “Impurity spectra of graphene under electric and magnetic fields” Type Editorial
Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 97 Issue 20 Pages 207403
Keywords Editorial; Condensed Matter Theory (CMT)
Abstract In a recent paper [Phys. Rev. B 89, 155403 (2014)], the authors investigated the spectrum of a Coulomb impurity in graphene in the presence of magnetic and electric fields using the coupled series expansion approach. In the first part of their paper, they investigated how Coulomb impurity states collapse in the presence of a perpendicular magnetic field. We argue that the obtained spectrum does not give information about the atomic collapse and that their interpretation of the spectrum regarding atomic collapse is not correct. We also argue that the obtained results are only valid up to the dimensionless charge vertical bar alpha vertical bar = 0.5 and, to obtain correct results for alpha > 0.5, a proper regularization of the Coulomb interaction is required. Here we present the correct numerical results for the spectrum for arbitrary values of alpha.
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Publisher Amer physical soc Place of Publication College pk Editor
Language Wos 000433288800015 Publication Date 2018-05-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 5 Open Access
Notes ; We thank Matthias Van der Donck for fruitful discussions. 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
Call Number (up) UA @ lucian @ c:irua:152042UA @ admin @ c:irua:152042 Serial 5017
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Author Mirzakhani, M.; Zarenia, M.; Peeters, F.M.
Title Edge states in gated bilayer-monolayer graphene ribbons and bilayer domain walls Type A1 Journal article
Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 123 Issue 20 Pages 204301
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the effective continuum model, the electron energy spectrum of gated bilayer graphene with a step-like region of decoupled graphene layers at the edge of the sample is studied. Different types of coupled-decoupled interfaces are considered, i.e., zigzag (ZZ) and armchair junctions, which result in significant different propagating states. Two non-valley-polarized conducting edge states are observed for ZZ type, which are mainly located around the ZZ-ended graphene layers. Additionally, we investigated both BA-BA and BA-AB domain walls in the gated bilayer graphene within the continuum approximation. Unlike the BA-BA domain wall, which exhibits gapped insulating behaviour, the domain walls surrounded by different stackings of bilayer regions feature valley-polarized edge states. Our findings are consistent with other theoretical calculations, such as from the tight-binding model and first-principles calculations, and agree with experimental observations. Published by AIP Publishing.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000433977200017 Publication Date 2018-05-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 3 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO), the BOF-UA (Bijzonder Onderzoeks Fonds), the Methusalem program of the Flemish Government, and Iran Nanotechnology Initiative Council (INIC). ; Approved Most recent IF: 2.068
Call Number (up) UA @ lucian @ c:irua:152044UA @ admin @ c:irua:152044 Serial 5020
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Author Dimitrievska, M.; Shea, P.; Kweon, K.E.; Bercx, M.; Varley, J.B.; Tang, W.S.; Skripov, A.V.; Stavila, V.; Udovic, T.J.; Wood, B.C.
Title Carbon Incorporation and Anion Dynamics as Synergistic Drivers for Ultrafast Diffusion in Superionic LiCB11H12 and NaCB11H12 Type A1 Journal article
Year 2018 Publication Advanced energy materials Abbreviated Journal Adv Energy Mater
Volume 8 Issue 15 Pages 1703422
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The disordered phases of LiCB11H12 and NaCB11H12 possess superb superionic conductivities that make them suitable as solid electrolytes. In these materials, cation diffusion correlates with high orientational mobilities of the CB11H12- anions; however, the precise relationship has yet to be demonstrated. In this work, ab initio molecular dynamics and quasielastic neutron scattering are combined to probe anion reorientations and their mechanistic connection to cation mobility over a range of timescales and temperatures. It is found that anions do not rotate freely, but rather transition rapidly between orientations defined by the cation sublattice symmetry. The symmetry-breaking carbon atom in CB11H12- also plays a critical role by perturbing the energy landscape along the instantaneous orientation of the anion dipole, which couples fluctuations in the cation probability density directly to the anion motion. Anion reorientation rates exceed 3 x 10(10) s(-1), suggesting the underlying energy landscape fluctuates dynamically on diffusion-relevant timescales. Furthermore, carbon is found to modify the orientational preferences of the anions and aid rotational mobility, creating additional symmetry incompatibilities that inhibit ordering. The results suggest that synergy between the anion reorientational dynamics and the carbon-modified cation-anion interaction accounts for the higher ionic conductivity in CB11H12- salts compared with B12H122-.
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Publisher WILEY-VCH Verlag GmbH & Co. Place of Publication Weinheim Editor
Language Wos 000434031400026 Publication Date 2018-02-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1614-6832; 1614-6840 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 16.721 Times cited 20 Open Access OpenAccess
Notes ; This work was performed in part under the auspices of the U.S. Department of Energy at Lawrence Livermore National Laboratory (LLNL) under Contract No. DE-AC52-07NA27344 and funded by Laboratory Directed Research and Development Grant 15-ERD-022. Computing support came from the LLNL Institutional Computing Grand Challenge program. This work was also performed in part within the assignment of the Russian Federal Agency of Scientific Organizations (program “Spin” No. 01201463330). The authors gratefully acknowledge support from the Russian Foundation for Basic Research under Grant No. 15-03-01114 and the Ural Branch of the Russian Academy of Sciences under Grant No. 15-9-2-9. A.V.S. gratefully acknowledges travel support from CRDF Global in conjunction with this work under Grant No. FSCX-15-61826-0. M.D. gratefully acknowledges research support from the Hydrogen Materials-Advanced Research Consortium (HyMARC), established as part of the Energy Materials Network under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Fuel Cell Technologies Office, under Contract No. DE-AC36-08GO28308. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy National Nuclear Security Administration under Contract No. DE-AC04-94AL85000. This work utilized facilities supported in part by the National Science Foundation under Agreement No. DMR-1508249. The views, opinions, findings, and conclusions stated herein are those of the authors and do not necessarily reflect those of CRDF Global, or the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. ; Approved Most recent IF: 16.721
Call Number (up) UA @ lucian @ c:irua:152045 Serial 5015
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Author Gauquelin, N.; Zhang, H.; Zhu, G.; Wei, J.Y.T.; Botton, G.A.
Title Atomic-scale identification of novel planar defect phases in heteroepitaxial YBa2Cu3O7-\delta thin films Type A1 Journal article
Year 2018 Publication AIP advances Abbreviated Journal Aip Adv
Volume 8 Issue 5 Pages 055022
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We have discovered two novel types of planar defects that appear in heteroepitaxial YBa2Cu3O7-delta(YBCO123) thin films, grown by pulsed-laser deposition (PLD) either with or without a La2/3Ca1/3MnO3 (LCMO) overlayer, using the combination of highangle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging and electron energy loss spectroscopy (EELS) mapping for unambiguous identification. These planar lattice defects are based on the intergrowth of either a BaO plane between two CuO chains or multiple Y-O layers between two CuO2 planes, resulting in non-stoichiometric layer sequences that could directly impact the high-Tc superconductivity. (C) 2018 Author(s).
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Publisher American Institute of Physics Place of Publication Melville, NY Editor
Language Wos 000433954000022 Publication Date 2018-05-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2158-3226 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.568 Times cited 1 Open Access OpenAccess
Notes ; We are thankful to Julia Huang for FIB TEM sample preparation. This work is supported by NSERC (through Discovery Grants to GAB and JYTW) and CIFAR. The electron microscopy work was carried out at the Canadian Centre for Electron Microscopy, a National Facility supported by McMaster University, the Canada Foundation for Innovation and NSERC. N.G. acknowledges H. Idrissi for useful discussions. ; Approved Most recent IF: 1.568
Call Number (up) UA @ lucian @ c:irua:152063 Serial 5013
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Author Bhat, S.G.; Gauquelin, N.; Sebastian, N.K.; Sil, A.; Béché, A.; Verbeeck, J.; Samal, D.; Kumar, P.S.A.
Title Orthorhombic vs. hexagonal epitaxial SrIrO3 thin films : structural stability and related electrical transport properties Type A1 Journal article
Year 2018 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett
Volume 122 Issue 2 Pages 28003
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Metastable orthorhombic SrIrO3 (SIO) is an arch-type spin-orbit coupled material. We demonstrate here a controlled growth of relatively thick (200 nm) SIO films that transform from bulk “6H-type” structure with monoclinic distortion to an orthorhombic lattice by controlling growth temperature. Extensive studies based on high-resolution X-ray diffraction and transmission electron microscopy infer a two distinct structural phases of SIO. Electrical transport reveals a weak temperature-dependent semi-metallic character for both phases. However, the temperature-dependent Hall-coefficient for the orthorhombic SIO exhibits a prominent sign change, suggesting a multiband character in the vicinity of E-F. Our findings thus unravel the subtle structure-property relation in SIO epitaxial thin films. Copyright (C) EPLA, 2018
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Publisher Place of Publication Paris Editor
Language Wos 000435517300001 Publication Date 2018-06-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0295-5075 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.957 Times cited 4 Open Access Not_Open_Access
Notes ; SGB and DS acknowledge useful discussions with E. P. Houwman, University of Twente, on X-ray diffraction. DS would like to thank H. Takagi, Max-Planck Institute for Solid State Research, Stuttgart, for the fruitful discussion on the transport properties of SIO thin films. SGB and NKS thank A. Aravind, Bishop Moore College, Mavelikara, for his valuable inputs while depositing the thin films of SIO. SGB, NKS and PSAK acknowledge Nano Mission Council, Department of Science & Technology, India, for the funding. DS acknowledges the financial support from Max-Planck Society through MaxPlanck Partner Group. NG, AB and JV acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G093417N. ; Approved Most recent IF: 1.957
Call Number (up) UA @ lucian @ c:irua:152074UA @ admin @ c:irua:152074 Serial 5034
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Author Hai, G.-Q.; Candido, L.; Brito, B.G.A.; Peeters, F.M.
Title Electron pairing: from metastable electron pair to bipolaron Type A1 Journal article
Year 2018 Publication Journal of physics communications Abbreviated Journal
Volume 2 Issue 3 Pages Unsp 035017
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Starting from the shell structure in atoms and the significant correlation within electron pairs, we distinguish the exchange-correlation effects between two electrons of opposite spins occupying the same orbital from the average correlation among many electrons in a crystal. In the periodic potential of the crystal with lattice constant larger than the effective Bohr radius of the valence electrons, these correlated electron pairs can form a metastable energy band above the corresponding single-electron band separated by an energy gap. In order to determine if these metastable electron pairs can be stabilized, we calculate the many-electron exchange-correlation renormalization and the polaron correction to the two-band system with single electrons and electron pairs. We find that the electron-phonon interaction is essential to counterbalance the Coulomb repulsion and to stabilize the electron pairs. The interplay of the electron-electron and electron-phonon interactions, manifested in the exchange-correlation energies, polaron effects, and screening, is responsible for the formation of electron pairs (bipolarons) that are located on the Fermi surface of the single-electron band.
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Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000434996900022 Publication Date 2018-02-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2399-6528 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 9 Open Access
Notes ; This work was supported by the Brazilian agencies FAPESP and CNPq. GQH would like to thank Prof. Bangfen Zhu for his invaluable support and expert advice. ; Approved Most recent IF: NA
Call Number (up) UA @ lucian @ c:irua:152079UA @ admin @ c:irua:152079 Serial 5022
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Author Bizindavyi, J.; Verhulst, A.S.; Smets, Q.; Verreck, D.; Sorée, B.; Groeseneken, G.
Title Band-Tails Tunneling Resolving the Theory-Experiment Discrepancy in Esaki Diodes Type A1 Journal article
Year 2018 Publication IEEE journal of the Electron Devices Society Abbreviated Journal Ieee J Electron Devi
Volume 6 Issue 1 Pages 633-641
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Discrepancies exist between the theoretically predicted and experimentally measured performance of band-to-band tunneling devices, such as Esaki diodes and tunnel field-effect transistors (TFETs). We resolve this discrepancy for highly-doped, direct-bandgap Esaki diodes by successfully calibrating a semi-classical model for high-doping-induced ballistic band-tails tunneling currents at multiple temperatures with two In0.53Ga0.47As Esaki diodes using their SIMS doping profiles, C-V characteristics and their forward-bias current density in the negative differential resistance (NDR) regime. The current swing in the NDR regime is shown not to be linked to the band-tails Urbach energy. We further demonstrate theoretically that the calibrated band-tails contribution is also the dominant band-tails contribution to the subthreshold swing of the corresponding TFETs. Lastly, we verify that the presented procedure is applicable to all direct-bandgap semiconductors by successfully applying it to InAs Esaki diodes in literature.
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Publisher IEEE, Electron Devices Society Place of Publication New York, N.Y. Editor
Language Wos 000435505000013 Publication Date 2018-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2168-6734 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.141 Times cited 5 Open Access
Notes ; J. Bizindavyi gratefully acknowledges FWO-Vlaanderen for a Strategic Basic Research PhD fellowship. ; Approved Most recent IF: 3.141
Call Number (up) UA @ lucian @ c:irua:152097UA @ admin @ c:irua:152097 Serial 5014
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Author Zhao, C.X.; Xu, W.; Dong, H.M.; Yu, Y.; Qin, H.; Peeters, F.M.
Title Enhancement of plasmon-photon coupling in grating coupled graphene inside a Fabry-Perot cavity Type A1 Journal article
Year 2018 Publication Solid state communications Abbreviated Journal Solid State Commun
Volume 280 Issue 280 Pages 45-49
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a theoretical investigation of the plasmon-polariton modes in grating coupled graphene inside a Fabry-Perot cavity. The cavity or photon modes of the device are determined by the Finite Difference Time Domain (FDTD) simulations and the corresponding plasmon-polariton modes are obtained by applying a many-body self-consistent field theory. We find that in such a device structure, the electric field strength of the incident electromagnetic (EM) field can be significantly enhanced near the edges of the grating strips. Thus, the strong coupling between the EM field and the plasmons in graphene can be achieved and the features of the plasmon-polariton oscillations in the structure can be observed. It is found that the frequencies of the plasmon-polariton modes are in the terahertz (THz) bandwidth and depend sensitively on electron density which can be tuned by applying a gate voltage. Moreover, the coupling between the cavity photons and the plasmons in graphene can be further enhanced by increasing the filling factor of the device. This work can help us to gain an in-depth understanding of the THz plasmonic properties of graphene-based structures.
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Publisher Place of Publication New York, N.Y. Editor
Language Wos 000439059600008 Publication Date 2018-06-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.554 Times cited 1 Open Access
Notes ; This work is supported by the National Natural Science Foundation of China (Grand No. 11604192 and Grant No. 11574319); the Center of Science and Technology of Hefei Academy of Science; the Ministry of Science and Technology of China (Grant No. 2011YQ130018); Department of Science and Technology of Yunnan Province; Chinese Academy of Sciences. ; Approved Most recent IF: 1.554
Call Number (up) UA @ lucian @ c:irua:152369UA @ admin @ c:irua:152369 Serial 5024
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Author Cautaerts, N.; Delville, R.; Stergar, E.; Schryvers, D.; Verwerft, M.
Title Tailoring the Ti-C nanoprecipitate population and microstructure of titanium stabilized austenitic steels Type A1 Journal article
Year 2018 Publication Journal of nuclear materials Abbreviated Journal J Nucl Mater
Volume 507 Issue 507 Pages 177-187
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The present work reports on the microstructural evolution of a new heat of 24% cold worked austenitic DIN 1.4970 (15-15Ti) nuclear cladding steel subjected to ageing heat treatments of varying duration between 500 and 800 degrees C (by steps of 100 degrees C). The primary aim was studying the finely dispersed Ti-C nanoprecipitate population, which are thought to be beneficial for creep and swelling resistance during service. Their size distribution and number density were estimated through dark field imaging and bright field Moire imaging techniques in the transmission electron microscope. Nanoprecipitates formed at and above 600 degrees C, which is a lower temperature than previously reported. The observed nucleation, growth and coarsening behavior of the nanoprecipitates were consistent with simple diffusion arguments. The formation of nanoprecipitates coincided with significant dissociation of dislocations as evidenced by weak beam dark field imaging. Possible mechanisms, including Silcock's stacking fault growth model and Suzuki segregation, are discussed. Recrystallization observed after extended ageing at 800 degrees C caused the redissolution of nanoprecipitates. Large primary Ti(C,N) and (Ti,Mo)C precipitates that occur in the as-received material, and M23C6 precipitates that nucleate on grain boundaries at low temperatures were also characterized by a selective dissolution procedure involving filtration, X-ray diffraction and quantitative Rietveld refinement. The partitioning of key elements between the different phases was derived by combining these findings and was consistent with thermodynamic considerations and the processing history of the steel. (C) 2018 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000438019800021 Publication Date 2018-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3115 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.048 Times cited 1 Open Access Not_Open_Access
Notes ; We would like to acknowledge ENGIE, SCK.CEN, the SCK.CEN academy and the MYRRHA project for the financial support of this work. Special thanks to T. Wangle and P. Dries for their help with filtration and gravimetry. Also thanks to Dr. G. Leinders for the discussions on XRD and Rietveld refinement. Thanks to E. Charalampopoulou and A. Youssef for assisting with the dissolution experiments. ; Approved Most recent IF: 2.048
Call Number (up) UA @ lucian @ c:irua:152382 Serial 5043
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Author Kalashami, H.G.; Neek-Amal, M.; Peeters, F.M.
Title Slippage dynamics of confined water in graphene oxide capillaries Type A1 Journal article
Year 2018 Publication Physical review materials Abbreviated Journal
Volume 2 Issue 7 Pages 074004
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The permeation of water between neighboring graphene oxide (GO) flakes, i.e., 2D nanochannels, are investigated using a simple model for the GO membrane. We simulate the hydrophilic behavior of nanocapillaries and study the effect of surface charge on the dynamical properties of water flow and the influence of Na+ and Cl- ions on water permeation. Our approach is based on extensive equilibrium molecular dynamics simulations to obtain a better understanding of water permeation through charged nanochannels in the presence of ions. We found significant change in the slippage dynamics of confined water such as a profound increase in viscosity/slip length with increasing charges over the surface. The slip length decreases one order of magnitude (i.e., 1/30) with increasing density of surface charge, while it increases by a factor of 2 with ion concentration. We found that commensurability induced by nanoconfinement plays an important role on the intrinsic dynamical properties of water.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000439435200006 Publication Date 2018-07-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 1 Open Access
Notes ; We acknowledge fruitful discussions with Andre K. Geim, Irina Grigorieva, and Rahul R. Nair. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; Approved Most recent IF: NA
Call Number (up) UA @ lucian @ c:irua:152409UA @ admin @ c:irua:152409 Serial 5128
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Author Tong, Y.; Yao, E.-P.; Manzi, A.; Bladt, E.; Wang, K.; Doeblinger, M.; Bals, S.; Mueller-Buschbaum, P.; Urban, A.S.; Polavarapu, L.; Feldmann, J.
Title Spontaneous self-assembly of Perovskite nanocrystals into electronically coupled supercrystals : toward filling the green gap Type A1 Journal article
Year 2018 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 30 Issue 30 Pages 1801117
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Self-assembly of nanoscale building blocks into ordered nanoarchitectures has emerged as a simple and powerful approach for tailoring the nanoscale properties and the opportunities of using these properties for the development of novel optoelectronic nanodevices. Here, the one-pot synthesis of CsPbBr3 perovskite supercrystals (SCs) in a colloidal dispersion by ultrasonication is reported. The growth of the SCs occurs through the spontaneous self-assembly of individual nanocrystals (NCs), which form in highly concentrated solutions of precursor powders. The SCs retain the high photoluminescence (PL) efficiency of their NC subunits, however also exhibit a redshifted emission wavelength compared to that of the individual nanocubes due to interparticle electronic coupling. This redshift makes the SCs pure green emitters with PL maxima at approximate to 530-535 nm, while the individual nanocubes emit a cyan-green color (approximate to 512 nm). The SCs can be used as an emissive layer in the fabrication of pure green light-emitting devices on rigid or flexible substrates. Moreover, the PL emission color is tunable across the visible range by employing a well-established halide ion exchange reaction on the obtained CsPbBr3 SCs. These results highlight the promise of perovskite SCs for light emitting applications, while providing insight into their collective optical properties.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000438709400019 Publication Date 2018-06-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 161 Open Access OpenAccess
Notes ; This research work was supported by the Bavarian State Ministry of Science, Research, and Arts through the grant “Solar Technologies go Hybrid (SolTech),” by the China Scholarship Council (Y.T. and K.W.), by the European Union's Horizon 2020 research and innovation program under the Marie Skodowska-Curie Grant Agreement COMPASS No. 691185 and by LMU Munich's Institutional Strategy LMUexcellent within the framework of the German Excellence Initiative (L.P., J.F. and A.S.U.). E.B. and S.B. acknowledge financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). The authors would like to thank Alexander Richter for helpful discussions. ; ecas_Sara Approved Most recent IF: 19.791
Call Number (up) UA @ lucian @ c:irua:152413UA @ admin @ c:irua:152413 Serial 5129
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Author Zarenia, M.; Hamilton, A.R.; Peeters, F.M.; Neilson, D.
Title Multiband mechanism for the sign reversal of Coulomb drag observed in double bilayer graphene heterostructures Type A1 Journal article
Year 2018 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 121 Issue 3 Pages 036601
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Coupled 2D sheets of electrons and holes are predicted to support novel quantum phases. Two experiments of Coulomb drag in electron-hole (e-h) double bilayer graphene (DBLG) have reported an unexplained and puzzling sign reversal of the drag signal. However, we show that this effect is due to the multiband character of DBLG. Our multiband Fermi liquid theory produces excellent agreement and captures the key features of the experimental drag resistance for all temperatures. This demonstrates the importance of multiband effects in DBLG: they have a strong effect not only on superfluidity, but also on the drag.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000438883600008 Publication Date 2018-07-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 7 Open Access
Notes ; We are grateful to Cory Dean, Emanuel Tutuc, and their research groups for discussing details of their experiments with us. This work was partially supported by the Flemish Science Foundation (FWO-Vl), the Methusalem program of the Flemish government, and the Australian Government through the Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies (Project No. CE170100039). D. N. acknowledges support from the University of Camerino FAR project CESEMN. ; Approved Most recent IF: 8.462
Call Number (up) UA @ lucian @ c:irua:152416UA @ admin @ c:irua:152416 Serial 5116
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Author Zhou, K.-G.; Vasu, K.S.; Cherian, C.T.; Neek-Amal, M.; Zhang, J.C.; Ghorbanfekr-Kalashami, H.; Huang, K.; Marshall, O.P.; Kravets, V.G.; Abraham, J.; Su, Y.; Grigorenko, A.N.; Pratt, A.; Geim, A.K.; Peeters, F.M.; Novoselov, K.S.; Nair, R.R.
Title Electrically controlled water permeation through graphene oxide membranes Type A1 Journal article
Year 2018 Publication Nature Abbreviated Journal Nature
Volume 559 Issue 7713 Pages 236-+
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Controlled transport of water molecules through membranes and capillaries is important in areas as diverse as water purification and healthcare technologies(1-7). Previous attempts to control water permeation through membranes (mainly polymeric ones) have concentrated on modulating the structure of the membrane and the physicochemical properties of its surface by varying the pH, temperature or ionic strength(3,8). Electrical control over water transport is an attractive alternative; however, theory and simulations(9-14) have often yielded conflicting results, from freezing of water molecules to melting of ice(14-16) under an applied electric field. Here we report electrically controlled water permeation through micrometre-thick graphene oxide membranes(17-21). Such membranes have previously been shown to exhibit ultrafast permeation of water(17,22) and molecular sieving properties(18,21), with the potential for industrial-scale production. To achieve electrical control over water permeation, we create conductive filaments in the graphene oxide membranes via controllable electrical breakdown. The electric field that concentrates around these current-carrying filaments ionizes water molecules inside graphene capillaries within the graphene oxide membranes, which impedes water transport. We thus demonstrate precise control of water permeation, from ultrafast permeation to complete blocking. Our work opens up an avenue for developing smart membrane technologies for artificial biological systems, tissue engineering and filtration.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000438240900052 Publication Date 2018-07-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 40.137 Times cited 216 Open Access
Notes ; This work was supported by the Royal Society, Engineering and Physical Sciences Research Council, UK (EP/K016946/1, EP/N013670/1 and EP/P00119X/1), British Council (award reference number 279336045), European Research Council (contract 679689) and Lloyd's Register Foundation. We thank J. Waters for assisting with X-ray measurements and G. Yu for electrical measurements. ; Approved Most recent IF: 40.137
Call Number (up) UA @ lucian @ c:irua:152420UA @ admin @ c:irua:152420 Serial 5096
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Author Leus, K.; Folens, K.; Nicomel, N.R.; Perez, J.P.H.; Filippousi, M.; Meledina, M.; Dirtu, M.M.; Turner, S.; Van Tendeloo, G.; Garcia, Y.; Du Laing, G.; Van Der Voort, P.
Title Removal of arsenic and mercury species from water by covalent triazine framework encapsulated \gamma-Fe2O3 nanoparticles Type A1 Journal article
Year 2018 Publication Journal of hazardous materials Abbreviated Journal J Hazard Mater
Volume 353 Issue 353 Pages 312-319
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The covalent triazine framework, CTF-1, served as host material for the in situ synthesis of Fe2O3 nanoparticles. The composite material consisted of 20 +/- 2 m% iron, mainly in gamma-Fe2O3 phase. The resulting gamma-Fe2O3@CTF-1 was examined for the adsorption of As-III, As-V and H-II from synthetic solutions and real surface-, ground- and wastewater. The material shows excellent removal efficiencies, independent from the presence of Ca2+, Mg2+ or natural organic matter and only limited dependency on the presence of phosphate ions. Its adsorption capacity towards arsenite (198.0 mg g(-1)), arsenate (102.3 mg g(-1)) and divalent mercury (165.8 mg g(-1)) belongs amongst the best-known adsorbents, including many other iron-based materials. Regeneration of the adsorbent can be achieved for use over multiple cycles without a decrease in performance by elution at 70 degrees C with 0.1 M NaOH, followed by a stirring step in a 5 m% H2O2 solution for As or 0.1 M thiourea and 0.001 M HCl for Hg. In highly contaminated water (100 mu gL(-1)), the adsorbent polishes the water quality to well below the current WHO limits.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000438002800035 Publication Date 2018-04-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3894 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.065 Times cited 22 Open Access OpenAccess
Notes ; Karen Leus acknowledges financial support from Ghent University. Nina Ricci Nicomel and Jeffrey Paulo H. Perez thank the funding of the VLIR-UOS. Marinela M. Dirtu acknowledges F.R.S.-FNRS for a Charge de recherches position. Stuart Turner gratefully acknowledges the FWO Vlaanderen for a post-doctoral scholarship. The Titan microscope used for this investigation was partially funded by the Hercules foundation of the Flemish government. This work was supported by the Belgian IAP-PAI network. ; Approved Most recent IF: 6.065
Call Number (up) UA @ lucian @ c:irua:152430 Serial 5124
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Author Contino, A.; Ciofi, I.; Wu, X.; Asselberghs, I.; Celano, U.; Wilson, C.J.; Tokei, Z.; Groeseneken, G.; Sorée, B.
Title Modeling of edge scattering in graphene interconnects Type A1 Journal article
Year 2018 Publication IEEE electron device letters Abbreviated Journal Ieee Electr Device L
Volume 39 Issue 7 Pages 1085-1088
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Graphene interconnects are being considered as a promising candidate for beyond CMOS applications, thanks to the intrinsic higher carrier mobility, lower aspect ratio and better reliability with respect to conventional Cu damascene interconnects. However, similarly to Cu, line edge roughness can seriously affect graphene resistance, something which must be taken into account when evaluating the related performance benefits. In this letter, we present a model for assessing the impact of edge scattering on the resistance of graphene interconnects. Our model allows the evaluation of the total mean free path in graphene lines as a function of graphene width, diffusive scattering probability and edge roughness standard deviation and autocorrelation length. We compare our model with other models from literature by benchmarking them using the same set of experimental data. We show that, as opposed to the considered models from literature, our model is capable to describe the mobility drop with scaling caused by significantly rough edges.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000437087400041 Publication Date 2018-05-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0741-3106 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.048 Times cited 1 Open Access
Notes ; ; Approved Most recent IF: 3.048
Call Number (up) UA @ lucian @ c:irua:152465UA @ admin @ c:irua:152465 Serial 5114
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Author Aierken, Y.; Leenaerts, O.; Peeters, F.M.
Title First-principles study of the stability and edge stress of nitrogen-decorated graphene nanoribbons Type A1 Journal article
Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 97 Issue 23 Pages 235436
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Edge functionalization of graphene nanoribbons with nitrogen atoms for various adatom configurations at armchair and zigzag edges are investigated. We provide comprehensive information on the electronic and magnetic properties and investigate the stability of the various systems. Two types of rippling of the nanoribbons, namely edge and bulk rippling depending on the sign of edge stress induced at the edge, are found. They are found to play the decisive role for the stability of the structures. We also propose a type of edge decoration in which every third nitrogen adatom at the zigzag edges is replaced by an oxygen atom. In this way, the electron count is compatible with a full aromatic structure, leading to additional stability and a disappearance of magnetism that is usually associated with zigzag nanoribbons.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000436192300006 Publication Date 2018-06-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 1 Open Access
Notes ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI. ; Approved Most recent IF: 3.836
Call Number (up) UA @ lucian @ c:irua:152478UA @ admin @ c:irua:152478 Serial 5104
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Author Tang, Y.; Hunter, E.C.; Battle, P.D.; Hendrickx, M.; Hadermann, J.; Cadogan, J.M.
Title Ferrimagnetism as a consequence of unusual cation ordering in the Perovskite SrLa2FeCoSbO9 Type A1 Journal article
Year 2018 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 57 Issue 12 Pages 7438-7445
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A polycrystalline sample of SrLa2FeCoSbO9 has been prepared in a solid-state reaction and studied by a combination of electron microscopy, magnetometry, Mossbauer spectroscopy, X-ray diffraction, and neutron diffraction. The compound adopts a monoclinic (space group P2(1)/n; a = 5.6218(6), b = 5.6221(6), c = 7.9440(8) angstrom, beta = 90.050(7)degrees at 300 K) perovskite-like crystal structure with two crystallographically distinct six-coordinate sites. One of these sites is occupied by 2/3 Co-2(+),1/3 Fe3+ and the other by 2/3 Sb5+, 1/3 Fe3+. This pattern of cation ordering results in a transition to a ferrimagnetic phase at 215 K. The magnetic moments on nearest-neighbor, six-coordinate cations align in an antiparallel manner, and the presence of diamagnetic Sb5+ on only one of the two sites results in a nonzero remanent magnetization of similar to 1 mu(B) per formula unit at 5 K.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000436023800073 Publication Date 2018-05-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 6 Open Access Not_Open_Access
Notes ; PDB, ECH, and JH acknowledge support from EPSRC under grant EP/M0189954/1. We would like to thank the STFC for the award of beamtime at the ISIS Neutron and Muon Source (RB 1610100), and we thank Dr. I. da Silva for the assistance provided. We also thank Dr. R Paria Sena for help with the HAADF-STEM and STEM-EDX experiments. ; Approved Most recent IF: 4.857
Call Number (up) UA @ lucian @ c:irua:152485 Serial 5103
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Author Bueken, B.; Van Velthoven, N.; Willhammar, T.; Stassin, T.; Stassen, I.; Keen, D.A.; Baron, G.V.; Denayer, J.F.M.; Ameloot, R.; Bals, S.; De Vos, D.; Bennett, T.D.
Title Gel-based morphological design of zirconium metal-organic frameworks Type A1 Journal article
Year 2017 Publication Chemical science Abbreviated Journal Chem Sci
Volume 8 Issue 8 Pages 3939-3948
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The ability of metal-organic frameworks (MOFs) to gelate under specific synthetic conditions opens up new opportunities in the preparation and shaping of hierarchically porous MOF monoliths, which could be directly implemented for catalytic and adsorptive applications. In this work, we present the first examples of xero-or aerogel monoliths consisting solely of nanoparticles of several prototypical Zr4+-based MOFs: UiO-66-X (X – H, NH2, NO2, (OH)(2)), UiO-67, MOF-801, MOF-808 and NU-1000. High reactant and water concentrations during synthesis were observed to induce the formation of gels, which were converted to monolithic materials by drying in air or supercritical CO2. Electron microscopy, combined with N-2 physisorption experiments, was used to show that irregular nanoparticle packing leads to pure MOF monoliths with hierarchical pore systems, featuring both intraparticle micropores and interparticle mesopores. Finally, UiO-66 gels were shaped into monolithic spheres of 600 mm diameter using an oil-drop method, creating promising candidates for packed-bed catalytic or adsorptive applications, where hierarchical pore systems can greatly mitigate mass transfer limitations.
Address
Corporate Author Thesis
Publisher Royal Society of Chemistry Place of Publication Cambridge Editor
Language Wos 000400553000077 Publication Date 2017-03-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-6520 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.668 Times cited 168 Open Access OpenAccess
Notes ; B. B., T. S. and I. S. acknowledge the FWO Flanders (doctoral and post-doctoral grants). T. W. acknowledges a post-doctoral grant from the Swedish Research Council. T. D. B. acknowledges the Royal Society (University Research Fellowship) and Trinity Hall (University of Cambridge) for funding. S. B. and D. D. V. are grateful for funding by Belspo (IAP 7/05 P6/27) and by the FWO Flanders. D. D. V. further acknowledges funding from the European Research Council (project H-CCAT). S. B. acknowledges financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). The authors acknowledge Arnau Carne and Shuhei Furukawa for assistance with supercritical CO<INF>2</INF> extraction, and Charles Ghesquiere for assistance in synthesis. ; Ecas_Sara Approved Most recent IF: 8.668
Call Number (up) UA @ lucian @ c:irua:152643UA @ admin @ c:irua:152643 Serial 5143
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Author Van Tendeloo, L.; Wangermez, W.; Vandekerkhove, A.; Willhammar, T.; Bals, S.; Maes, A.; Martens, J.A.; Kirschhock, C.E.A.; Breynaert, E.
Title Postsynthetic high-alumina zeolite crystal engineering in organic free hyper-alkaline media Type A1 Journal article
Year 2017 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 29 Issue 29 Pages 629-638
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Postsynthetic modification of high -alumina zeolites in hyper alkaline media can be tailored toward alteration of framework topology, crystal size and morphology, or desired Si/A1 ratio. FAU, EMT, MAZ, KFI, HEU, and LTA starting materials were treated with 1.2 M MOH (M = Na, K, RE, or Cs), leading to systematic ordered porosity or fully transformed frameworks with new topology and adjustable Si/Al ratio. In addition to the versatility of this tool for zeolite crystal engineering, these alterations improve understanding of the crystal chemistry. Such knowledge can guide further development in zeolite crystal engineering. Postsynthetic alteration also provides insight on the long-term stability of aluminosilicate zeolites that are used as a sorption sink in concrete -based waste disposal facilities in harsh alkaline conditions.
Address
Corporate Author Thesis
Publisher American Chemical Society Place of Publication Washington, D.C Editor
Language Wos 000392891700021 Publication Date 2016-12-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 16 Open Access OpenAccess
Notes ; This work was supported by long-term structural funding by the Flemish Government (Methusalem grant of Prof. J. Martens) and by ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and Fissile Materials, as part of the program on surface disposal of Belgian Category A waste. The Belgian government is acknowledged for financing the interuniversity poles of attraction (IAP-PAI). S.B. acknowledges financial support from European Research Council (ERC Advanced Grant No. 24691-COUNTATOMS, ERC Starting Grant No. 335078-COLOURATOMS). ; Ecas_Sara Approved Most recent IF: 9.466
Call Number (up) UA @ lucian @ c:irua:152674UA @ admin @ c:irua:152674 Serial 5145
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Author Vodolazov, D.Y.; Berdiyorov, G.; Peeters, F.M.
Title Negative magnetoresistance in thin superconducting films with parallel orientation of current and magnetic field Type A1 Journal article
Year 2018 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 552 Issue 552 Pages 64-66
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Thin superconducting films can exhibit negative magnetoresistance when an in-plane external magnetic field is aligned parallel with the transport current. We explain this effect as due to appearance of parallel vortices in the plain of the film at the first critical magnetic field H-c1 which leads to an enhancement of the superconducting properties and impedes the motion of the current induced perpendicular vortices. Our theoretical results are based on a numerical solution of the time-dependent and stationary 3D Ginzburg-Landau equations.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000440786600012 Publication Date 2018-07-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 6 Open Access
Notes ; The work is supported by the Russian Science Foundation Project No. 17-72-30036 and the Malthusian programme of the Flemish government. ; Approved Most recent IF: 1.404
Call Number (up) UA @ lucian @ c:irua:153067UA @ admin @ c:irua:153067 Serial 5117
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Author Wu, S.-M.; Liu, X.-L.; Lian, X.-L.; Tian, G.; Janiak, C.; Zhang, Y.-X.; Lu, Y.; Yu, H.-Z.; Hu, J.; Wei, H.; Zhao, H.; Chang, G.-G.; Van Tendeloo, G.; Wang, L.-Y.; Yang, X.-Y.; Su, B.-L.
Title Homojunction of oxygen and titanium vacancies and its interfacial n-p effect Type A1 Journal article
Year 2018 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 30 Issue 32 Pages 1802173
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The homojunction of oxygen/metal vacancies and its interfacial n-p effect on the physiochemical properties are rarely reported. Interfacial n-p homojunctions of TiO2 are fabricated by directly decorating interfacial p-type titanium-defected TiO2 around n-type oxygen-defected TiO2 nanocrystals in amorphous-anatase homogeneous nanostructures. Experimental measurements and theoretical calculations on the cell lattice parameters show that the homojunction of oxygen and titanium vacancies changes the charge density of TiO2; a strong EPR signal caused by oxygen vacancies and an unreported strong titanium vacancies signal of 2D H-1 TQ-SQ MAS NMR are present. Amorphous-anatase TiO2 shows significant performance regarding the photogeneration current, photocatalysis, and energy storage, owing to interfacial n-type to p-type conductivity with high charge mobility and less structural confinement of amorphous clusters. A new homojunction of oxygen and titanium vacancies concept, characteristics, and mechanism are proposed at an atomic-/nanoscale to clarify the generation of oxygen vacancies and titanium vacancies as well as the interface electron transfer.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000440813300022 Publication Date 2018-06-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 39 Open Access Not_Open_Access
Notes ; This work was supported by National Key R&D Program of China (2017YFC1103800), National SFC (U1662134, U1663225, 51472190, 51611530672, 21711530705, 51503166, 21706199), ISTCP (2015DFE52870), PCSIRT (IRT_15R52), HPNSF (2016CFA033, 2017CFB487), and SKLPPC (PPC2016007). ; Approved Most recent IF: 19.791
Call Number (up) UA @ lucian @ c:irua:153106 Serial 5105
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Author Weng, Y.; Jia, Z.; Ding, L.; Muraishi, S.; Liu, Q.
Title Clustering behavior during natural aging and artificial aging in Al-Mg-Si alloys with different Ag and Cu addition Type A1 Journal article
Year 2018 Publication Microstructure And Processing Abbreviated Journal Mat Sci Eng A-Struct
Volume 732 Issue 732 Pages 273-283
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The effect of Ag and Cu addition on clustering behavior of Al-Mg-Si alloys during natural aging (NA) and artificial aging (AA) was investigated by hardness measurement, tensile test and atom probe tomography analysis. The results show that both Ag and Cu atoms could enter clusters and GP-zones, change the Mg/Si ratio and increase their volume fractions. Compared with the Al base alloy, the clusters in the Ag/Cu-added alloys more easily transform to beta" phases for size and compositional similarity, and the strengthening ability of these particles is enhanced by the increased volume fraction and shear modulus. In NA condition, Cu is greater in improving the volume fraction of clusters than Ag and thus produces higher T4 temper hardness. In AA condition, in contrary, Ag is more effective in facilitating the formation and growth of particles than Cu due to the stronger Ag-Mg interaction and the high diffusivity of Ag atoms in Al matrix, leading to highest hardening response. Compared to the Cu-added alloy, the Ag-added alloy shows higher precipitation kinetics during AA treatment and maintains a lower T4 temper hardness.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000441486100032 Publication Date 2018-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-5093 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.094 Times cited 11 Open Access OpenAccess
Notes ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant no. cstc2017zdcy-zdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant no. 106112016CDJXZ338825 and 106112017CDJQJ308822) and the program of China Scholarships Council (No. 201706050125). ; Approved Most recent IF: 3.094
Call Number (up) UA @ lucian @ c:irua:153107 Serial 5083
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Author Hu, L.; Amini, M.N.; Wu, Y.; Jin, Z.; Yuan, J.; Lin, R.; Wu, J.; Dai, Y.; He, H.; Lu, Y.; Lu, J.; Ye, Z.; Han, S.-T.; Ye, J.; Partoens, B.; Zeng, Y.-J.; Ruan, S.
Title Charge transfer doping modulated raman scattering and enhanced stability of black phosphorus quantum dots on a ZnO nanorod Type A1 Journal article
Year 2018 Publication Advanced Optical Materials Abbreviated Journal Adv Opt Mater
Volume 6 Issue 15 Pages 1800440
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Black phosphorus (BP) has recently triggered an unprecedented interest in the 2D community. However, many of its unique properties are not exploited and the well-known environmental vulnerability is not conquered. Herein, a type-I mixed-dimensional (0D-1D) van der Waals heterojunction is developed, where three-atomic-layer BP quantum dots (QDs) are assembled on a single ZnO nanorod (NR). By adjusting the indium (In) content in ZnO NRs, the degree and even the direction of surface charge transfer doping within the heterojunction can be tuned, which result in selective Raman scattering enhancements between ZnO and BP. The maximal enhancement factor is determined as 4340 for BP QDs with sub-ppm level. Furthermore, an unexpected long-term ambient stability (more than six months) of BP QDs is revealed, which is ascribed to the electron doping from ZnO:In NRs. The first demonstration of selective Raman enhancements between two inorganic semiconductors as well as the improved stability of BP shed light on this emerging 2D material.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000440815200023 Publication Date 2018-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2195-1071 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.875 Times cited 37 Open Access Not_Open_Access
Notes ; L. Hu and M. N. Amini contributed equally to this work. This work was supported by the National Natural Science Foundation of China under Grant Nos. 51502178, 81571763 and 81622026, the Shenzhen Science and Technology Project under Grant Nos. JCYJ20150324141711644, JCYJ20170412105400428, KQJSCX20170727101208249 and JCYJ20170302153853962. Parts of the computational calculations were carried out using the HPC infrastructure at University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the FWO-Vlaanderen and the Flemish Government (EWI Department). L. H. acknowledges the PhD Start-up Fund of Natural Science Foundation of Guangdong Province under Grand No. 2017A030310072. J. Y. acknowledges the funding of Shanghai Jiao Tong University (Nos. YG2016MS51 and YG2017MS54). ; Approved Most recent IF: 6.875
Call Number (up) UA @ lucian @ c:irua:153112UA @ admin @ c:irua:153112 Serial 5082
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Author Morozov, V.; Deyneko, D.; Basoyich, O.; Khaikina, E.G.; Spassky, D.; Morozov, A.; Chernyshev, V.; Abakumov, A.; Hadermann, J.
Title Incommensurately modulated structures and luminescence properties of the AgxSm(2-x)/3WO4 (x=0.286, 0.2) scheelites as thermographic phosphors Type A1 Journal article
Year 2018 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 30 Issue 14 Pages 4788-4798
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ag+ for Sm3+ substitution in the scheelite-type AgxSm(2-x)/3 square(1-2x)/3WO4 tungstates has been investigated for its influence on the cation-vacancy ordering and luminescence properties. A solid state method was used to synthesize the x = 0.286 and x = 0.2 compounds, which exhibited (3 + 1)D incommensurately modulated structures in the transmission electron microscopy study. Their structures were refined using high resolution synchrotron powder X-ray diffraction data. Under near-ultraviolet light, both compounds show the characteristic emission lines for (4)G(5/2) -> H-6(J) (J = 5/2, 7/2, 9/2, and 11/2) transitions of the Sm3+ ions in the range 550-720 nm, with the J = 9/2 transition at the similar to 648 nm region being dominant for all photoluminescence spectra. The intensities of the (4)G(5/2) -> H-6(9/2) and (4)G(5/2) -> H-6(7/2) bands have different temperature dependencies. The emission intensity ratios (R) for these bands vary reproducibly with temperature, allowing the use of these materials as thermographic phosphors.
Address
Corporate Author Thesis
Publisher American Chemical Society Place of Publication Washington, D.C Editor
Language Wos 000440105500037 Publication Date 2018-06-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 2 Open Access Not_Open_Access
Notes ; This research was supported by FWO (Project G039211N), Flanders Research Foundation. The research was carried out within the state assignment of FASO of Russia (Themes No. 0339-2016-0007). V.M. thanks the Russian Foundation for Basic Research (Grant 18-03-00611) for financial support. E.G.K. and O.B. acknowledge financial support from the Russian Foundation for Basic Research (Grant 16-03-00510). D.D. thanks the Foundation of the Russian Federation President (Grant MK-3502.2018.5) for financial support. We are grateful to the ESRF for granting the beamtime. V.C. is grateful for the financial support of the Russian Ministry of Science and Education (Project No. RFMEFI61616X0069). We are grateful to the ESRF for the access to ID22 station (experiment MA-3313). ; Approved Most recent IF: 9.466
Call Number (up) UA @ lucian @ c:irua:153156 Serial 5107
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Author van der Burgt, J.S.; Geuchies, J.J.; van der Meer, B.; Vanrompay, H.; Zanaga, D.; Zhang, Y.; Albrecht, W.; Petukhov, A.V.; Filion, L.; Bals, S.; Swart, I.; Vanmaekelbergh, D.
Title Cuboidal supraparticles self-assembled from cubic CsPbBr3 perovskite nanocrystals Type A1 Journal article
Year 2018 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 122 Issue 122 Pages 15706-15712
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Colloidal CsPbBr3 nanocrystals (NCs) have emerged as promising candidates for various opto-electronic applications, such as light-emitting diodes, photodetectors, and solar cells. Here, we report on the self-assembly of cubic NCs from an organic suspension into ordered cuboidal supraparticles (SPs) and their structural and optical properties. Upon increasing the NC concentration or by addition of a nonsolvent, the formation of the SPs occurs homogeneously in the suspension, as monitored by in situ X-ray scattering measurements. The three-dimensional structure of the SPs was resolved through high-angle annular dark-field scanning transmission electron microscopy and electron tomography. The NCs are atomically aligned but not connected. We characterize NC vacancies on superlattice positions both in the bulk and on the surface of the SPs. The occurrence of localized atomic-type NC vacancies-instead of delocalized ones-indicates that NC-NC attractions are important in the assembly, as we verify with Monte Carlo simulations. Even when assembled in SPs, the NCs show bright emission, with a red shift of about 30 meV compared to NCs in suspension.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000439003600071 Publication Date 2018-06-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 60 Open Access OpenAccess
Notes ; The authors thank Dr. Rajeev Dattani and Jacques Gorini from the ID02 beamline of the ESRF for their excellent assistance during the X-ray scattering experiments. We also thank Carlo van Overbeek, P. Tim Prins, and Federico Montanarella for their support during the synchrotron experiments. The authors gratefully acknowledge Prof. Dr. Alfons van Blaaderen for fruitful discussions. D.V. acknowledges funding from NWO-CW TOPPUNT “Superficial superstructures.” J.J.G. acknowledges the joint Debye and ESRF graduate programs for the financial support. H.V. gratefully acknowledges the financial support by the Flemish Fund for Scientific Research (FWO grant 1S32617NN). S.B. acknowledges the financial support from the European Research Council (ERC Starting grant # 335078-COLOURATOMS). Y.Z. acknowledges the financial support from the European Union's Horizon 2020 research and innovation program, under the Marie Sklodowska-Curie grant agreement #665501 through a FWO [PEGASUS]2 Marie Sklodowska-Curie fellowship (12U4917N). W.A. acknowledges the financial support from the European Research Council under the European Unions Seventh Framework Program (FP-2007-2013)/ERC Advanced grant agreement 291667 HierarSACol. ; ecas_Sara Approved Most recent IF: 4.536
Call Number (up) UA @ lucian @ c:irua:153161UA @ admin @ c:irua:153161 Serial 5087
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