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Author Pittarello, L.; Ji, G.; Yamaguchi, A.; Schryvers, D.; Debaille, V.; Claeys, P.
Title From olivine to ringwoodite : a TEM study of a complex process Type A1 Journal article
Year (up) 2015 Publication Meteoritics and Planetary Science Abbreviated Journal Meteorit Planet Sci
Volume 50 Issue 50 Pages 944-957
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The study of shock metamorphism of olivine might help to constrain impact events in the history of meteorites. Although shock features in olivine are well known, so far, there are processes that are not yet completely understood. In shock veins, olivine clasts with a complex structure, with a ringwoodite rim and a dense network of lamellae of unidentified nature in the core, have been reported in the literature. A highly shocked (S5-6), L6 meteorite, Asuka 09584, which was recently collected in Antarctica by a Belgian-Japanese joint expedition, contains this type of shocked olivine clasts and has been, therefore, selected for detailed investigations of these features by transmission electron microscopy (TEM). Petrographic, geochemical, and crystallographic studies showed that the rim of these shocked clasts consists of an aggregate of nanocrystals of ringwoodite, with lower Mg/Fe ratio than the unshocked olivine. The clast's core consists of an aggregate of iso-oriented grains of olivine and wadsleyite, with higher Mg/Fe ratio than the unshocked olivine. This aggregate is crosscut by veinlets of nanocrystals of olivine, with extremely low Mg/Fe ratio. The formation of the ringwoodite rim is likely due to solid-state, diffusion-controlled, transformation from olivine under high-temperature conditions. The aggregate of iso-oriented olivine and wadsleyite crystals is interpreted to have formed also by a solid-state process, likely by coherent intracrystalline nucleation. Following the compression, shock release is believed to have caused opening of cracks and fractures in olivine and formation of olivine melt, which has lately crystallized under postshock equilibrium pressure conditions as olivine.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000354258400008 Publication Date 2015-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1086-9379; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.391 Times cited 8 Open Access
Notes Approved Most recent IF: 2.391; 2015 IF: 3.104
Call Number c:irua:126058 Serial 1283
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Author da Silva, R.M.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M.; Albino Aguiar, J.
Title Giant paramagnetic Meissner effect in multiband superconductors Type A1 Journal article
Year (up) 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 5 Issue 5 Pages 12695
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Superconductors, ideally diamagnetic when in the Meissner state, can also exhibit paramagnetic behavior due to trapped magnetic flux. In the absence of pinning such paramagnetic response is weak, and ceases with increasing sample thickness. Here we show that in multiband superconductors paramagnetic response can be observed even in slab geometries, and can be far larger than any previous estimate – even multiply larger than the diamagnetic Meissner response for the same applied magnetic field. We link the appearance of this giant paramagnetic response to the broad crossover between conventional Type-I and Type-II superconductors, where Abrikosov vortices interact non-monotonically and multibody effects become important, causing unique flux configurations and their locking in the presence of surfaces.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000359143700001 Publication Date 2015-08-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 25 Open Access
Notes ; This work was supported by the Brazilian science agencies CAPES (PNPD 223038.003145/2011-00), CNPq (307552/2012-8, 141911/2012-3, and APV-4 02937/ 2013-9), and FACEPE (APQ-0202-1.05/10 and BCT-0278-1.05/11), the Flemish Science Foundation (FWO-Vl), and by the CNPq-FWO cooperation programme (CNPq 490297/2009-9). R.M.S. acknowledges support from the SRS PhD+ program of the University Cooperation for Development of the Flemish Interuniversity Council (VLIR-UOS). M.V.M. acknowledges support from CNPq (APV-4 02937/2013-9), FACEPE (APV-0034-1.05/14), and CAPES (BEX1392/11-5). ; Approved Most recent IF: 4.259; 2015 IF: 5.578
Call Number c:irua:127212 Serial 1339
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Author La Porta, A.; Sanchez-Iglesias, A.; Altantzis, T.; Bals, S.; Grzelczak, M.; Liz-Marzan, L.M.
Title Multifunctional self-assembled composite colloids and their application to SERS detection Type A1 Journal article
Year (up) 2015 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 7 Issue 7 Pages 10377-10381
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We present a simple method for the co-encapsulation of gold nanostars and iron-oxide nanoparticles into hybrid colloidal composites that are highly responsive to both light and external magnetic fields. Self-assembly was driven by hydrophobic interactions between polystyrene capped gold nanostars and iron oxide nanocrystals stabilized with oleic acid, upon addition of water. A block copolymer was then used to encapsulate the resulting spherical colloidal particle clusters, which thereby became hydrophilic. Electron microscopy analysis unequivocally shows that each composite particle comprises a single Au nanostar surrounded by a few hundreds of iron oxide nanocrystals. We demonstrate that this hybrid colloidal system can be used as an efficient substrate for surface enhanced Raman scattering, using common dyes as model molecular probes. The co-encapsulation of iron oxide nanoparticles renders the system magnetically responsive, so that application of an external magnetic field leads to particle accumulation and limits of detection are in the nM range.
Address A1 Article; Electron microscopy for materials research (EMAT);
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000355987300010 Publication Date 2015-04-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 51 Open Access OpenAccess
Notes 267867 Plasmaquo; 335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number c:irua:127003 Serial 3940
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Author Mourdikoudis, S.; Chirea, M.; Zanaga, D.; Altantzis, T.; Mitrakas, M.; Bals, S.; Marzán, L.M.; Pérez-Juste, J.; Pastoriza-Santos, I.
Title Governing the morphology of PtAu heteronanocrystals with improved electrocatalytic performance Type A1 Journal article
Year (up) 2015 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 7 Issue 7 Pages 8739-8747
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Platinumgold heteronanostructures comprising either dimer (PtAu) or coresatellite (Pt@Au) configurations were synthesized by means of a seeded growth procedure using platinum nanodendrites as seeds. Careful control of the reduction kinetics of the gold precursor can be used to direct the nucleation and growth of gold nanoparticles on either one or multiple surface sites simultaneously, leading to the formation of either dimers or coresatellite nanoparticles, respectively, in high yields. Characterization by electron tomography and high resolution electron microscopy provided a better understanding of the actual three-dimensional particle morphology, as well as the AuPt interface, revealing quasi-epitaxial growth of Au on Pt. The prepared PtAu bimetallic nanostructures are highly efficient catalysts for ethanol oxidation in alkaline solution, showing accurate selectivity, high sensitivity, and improved efficiency by generating higher current densities than their monometallic counterparts.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000354204400011 Publication Date 2015-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 41 Open Access OpenAccess
Notes 335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number c:irua:126354 Serial 1360
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Author Sahin, H.; Leenaerts, O.; Singh, S.K.; Peeters, F.M.
Title Graphane Type A1 Journal article
Year (up) 2015 Publication Wiley Interdisciplinary Reviews: Computational Molecular Science Abbreviated Journal Wires Comput Mol Sci
Volume 5 Issue 5 Pages 255-272
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Atomically thin crystals have recently been the focus of attention, in particular, after the synthesis of graphene, a monolayer hexagonal crystal structure of carbon. In this novel material class, the chemically derived graphenes have attracted tremendous interest. It was shown that, although bulk graphite is a chemically inert material, the surface of single layer graphene is rather reactive against individual atoms. So far, synthesis of several graphene derivatives have been reported such as hydrogenated graphene graphane' (CH), fluorographene (CF), and chlorographene (CCl). Moreover, the stability of bromine and iodine covered graphene were predicted using computational tools. Among these derivatives, easy synthesis, insulating electronic behavior and reversibly tunable crystal structure of graphane make this material special for future ultra-thin device applications. This overview surveys structural, electronic, magnetic, vibrational, and mechanical properties of graphane. We also present a detailed overview of research efforts devoted to the computational modeling of graphane and its derivatives. Furthermore recent progress in synthesis techniques and possible applications of graphane are reviewed as well. WIREs Comput Mol Sci 2015, 5:255-272. doi: 10.1002/wcms.1216 For further resources related to this article, please visit the . Conflict of interest: The authors have declared no conflicts of interest for this article.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000352862700001 Publication Date 2015-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1759-0876; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 14.016 Times cited 54 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. H. Sahin is supported by a FWO Pegasus Long Marie Curie Fellowship. ; Approved Most recent IF: 14.016; 2015 IF: 11.885
Call Number c:irua:125996 Serial 1366
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Author Pizzochero, M.; Leenaerts, O.; Partoens, B.; Martinazzo, R.; Peeters, F.M.
Title Hydrogen adsorption on nitrogen and boron doped graphene Type A1 Journal article
Year (up) 2015 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 27 Issue 27 Pages 425502
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Hydrogen adsorption on boron and nitrogen doped graphene is investigated in detail by means of first-principles calculations. A comprehensive study is performed of the structural, electronic, and magnetic properties of chemisorbed hydrogen atoms and atom pairs near the dopant sites. The main effect of the substitutional atoms is charge doping which is found to greatly affect the adsorption process by increasing the binding energy at the sites closest to the substitutional species. It is also found that doping does not induce magnetism despite the odd number of electrons per atom introduced by the foreign species, and that it quenches the paramagnetic response of chemisorbed H atoms on graphene. Overall, the effects are similar for B and N doping, with only minor differences in the adsorption energetics due to different sizes of the dopant atoms and the accompanying lattice distortions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000362573500008 Publication Date 2015-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 20 Open Access
Notes This work was supported by the Flemish Science Foundation (FWO-Vl). MP gratefully acknowledges the Condensed Matter Theory group at Universiteit Antwerpen for the hospitality during his stay. Approved Most recent IF: 2.649; 2015 IF: 2.346
Call Number c:irua:128759 Serial 3971
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Author Schoelz, J.K.; Xu, P.; Meunier, V.; Kumar, P.; Neek-Amal, M.; Thibado, P.M.; Peeters, F.M.
Title Graphene ripples as a realization of a two-dimensional Ising model : a scanning tunneling microscope study Type A1 Journal article
Year (up) 2015 Publication Physical review: B: condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 91 Issue 91 Pages 045413
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Ripples in pristine freestanding graphene naturally orient themselves in an array that is alternately curved-up and curved-down; maintaining an average height of zero. Using scanning tunneling microscopy (STM) to apply a local force, the graphene sheet will reversibly rise and fall in height until the height reaches 60%-70% of its maximum at which point a sudden, permanent jump occurs. We successfully model the ripples as a spin-half Ising magnetic system, where the height of the graphene plays the role of the spin. The permanent jump in height, controlled by the tunneling current, is found to be equivalent to an antiferromagnetic-to-ferromagnetic phase transition. The thermal load underneath the STM tip alters the local tension and is identified as the responsible mechanism for the phase transition. Four universal critical exponents are measured from our STM data, and the model provides insight into the statistical role of graphene's unusual negative thermal expansion coefficient.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000348762200011 Publication Date 2015-01-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 21 Open Access
Notes ; This work was supported in part by Office of Naval Research (USA) under Grant No. N00014-10-1-0181 and National Science Foundation (USA) under Grant No. DMR-0855358. F. M. Peeters and M. Neek-Amal were 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 c:irua:123866 Serial 1377
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Author Kuopanportti, P.; Orlova, N.V.; Milošević, M.V.
Title Ground-state multiquantum vortices in rotating two-species superfluids Type A1 Journal article
Year (up) 2015 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
Volume 91 Issue 91 Pages 043605
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We show numerically that a rotating, harmonically trapped mixture of two Bose-Einstein-condensed superfluids cancontrary to its single-species counterpartcontain a multiply quantized vortex in the ground state of the system. This giant vortex can occur without any accompanying single-quantum vortices, may either be coreless or have an empty core, and can be realized in a Rb87−K41 Bose-Einstein condensate. Our results not only provide a rare example of a stable, solitary multiquantum vortex but also reveal exotic physics stemming from the coexistence of multiple, compositionally distinct condensates in one system.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000352255200005 Publication Date 2015-04-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.925 Times cited 25 Open Access
Notes ; This work was supported by the Finnish Cultural Foundation, the Research Foundation – Flanders (FWO), and the Magnus Ehrnrooth Foundation. We thank E. Ruokokoski and T. P. Simula for valuable comments and discussions. ; Approved Most recent IF: 2.925; 2015 IF: 2.808
Call Number c:irua:124906 Serial 1388
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Author Hai, G.-Q.; Peeters, F.M.
Title Hamiltonian of a many-electron system with single-electron and electron-pair states in a two-dimensional periodic potential Type A1 Journal article
Year (up) 2015 Publication European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B
Volume 88 Issue 88 Pages 20
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Based on the metastable electron-pair energy band in a two-dimensional (2D) periodic potential obtained previously by Hai and Castelano [J. Phys.: Condens. Matter 26, 115502 (2014)], we present in this work a Hamiltonian of many electrons consisting of single electrons and electron pairs in the 2D system. The electron-pair states are metastable of energies higher than those of the single-electron states at low electron density. We assume two different scenarios for the single-electron band. When it is considered as the lowest conduction band of a crystal, we compare the obtained Hamiltonian with the phenomenological model Hamiltonian of a boson-fermion mixture proposed by Friedberg and Lee [Phys. Rev. B 40, 6745 (1989)]. Single-electron-electron-pair and electron-pair-electron-pair interaction terms appear in our Hamiltonian and the interaction potentials can be determined from the electron-electron Coulomb interactions. When we consider the single-electron band as the highest valence band of a crystal, we show that holes in this valence band are important for stabilization of the electron-pair states in the system.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000347776800005 Publication Date 2015-01-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6028;1434-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.461 Times cited 2 Open Access
Notes ; This work was supported by FAPESP and CNPq (Brazil). ; Approved Most recent IF: 1.461; 2015 IF: 1.345
Call Number c:irua:125317 Serial 1406
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Author Yalcin, A.O.; Goris, B.; van Dijk-Moes, R.J.A.; Fan, Z.; Erdamar, A.K.; Tichelaar, F.D.; Vlugt, T.J.H.; Van Tendeloo, G.; Bals, S.; Vanmaekelbergh, D.; Zandbergen, H.W.; van Huis, M.A.;
Title Heat-induced transformation of CdSe-CdS-ZnS coremultishell quantum dots by Zn diffusion into inner layers Type A1 Journal article
Year (up) 2015 Publication Chemical communications Abbreviated Journal Chem Commun
Volume 51 Issue 51 Pages 3320-3323
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this work, we investigate the thermal evolution of CdSeCdSZnS coremultishell quantum dots (QDs) in situ using transmission electron microscopy (TEM). Starting at a temperature of approximately 250 °C, Zn diffusion into inner layers takes place together with simultaneous evaporation of particularly Cd and S. As a result of this transformation, CdxZn1−xSeCdyZn1−yS coreshell QDs are obtained.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000349325000004 Publication Date 2014-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-7345;1364-548X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited 21 Open Access OpenAccess
Notes 262348 Esmi; Fwo; 246791 Countatoms; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 6.319; 2015 IF: 6.834
Call Number c:irua:132582 Serial 1412
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Author Vidick, D.; Ke, X.; Devillers, M.; Poleunis, C.; Delcorte, A.; Moggi, P.; Van Tendeloo, G.; Hermans, S.
Title Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers Type A1 Journal article
Year (up) 2015 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech
Volume 6 Issue 6 Pages 1287-1297
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Heterometal clusters containing Ru and Au, Co and/or Pt are anchored onto carbon nanotubes and nanofibers functionalized with chelating phosphine groups. The cluster anchoring yield is related to the amount of phosphine groups available on the nanocarbon surface. The ligands of the anchored molecular species are then removed by gentle thermal treatment in order to form nanoparticles. In the case of Au-containing clusters, removal of gold atoms from the clusters and agglomeration leads to a bimodal distribution of nanoparticles at the nanocarbon surface. In the case of Ru-Pt species, anchoring occurs without reorganization through a ligand exchange mechanism. After thermal treatment, ultrasmall (1-3 nm) bimetal Ru-Pt nanoparticles are formed on the surface of the nanocarbons. Characterization by high resolution transmission electron microscopy (HRTEM) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) confirms their bimetal nature on the nanoscale. The obtained bimetal nanoparticles supported on nanocarbon were tested as catalysts in ammonia synthesis and are shown to be active at low temperature and atmospheric pressure with very low Ru loading.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000355908400001 Publication Date 2015-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.127 Times cited 7 Open Access
Notes 246791 Countatoms; 262348 Esmi Approved Most recent IF: 3.127; 2015 IF: 2.670
Call Number c:irua:126431 Serial 1420
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Author Bacaksiz, C.; Sahin, H.; Ozaydin, H.D.; Horzum, S.; Senger, R.T.; Peeters, F.M.
Title Hexagonal A1N : dimensional-crossover-driven band-gap transition Type A1 Journal article
Year (up) 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 91 Issue 91 Pages 085430
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Motivated by a recent experiment that reported the successful synthesis of hexagonal (h) AlN [Tsipas et al., Appl. Phys. Lett. 103, 251605 (2013)], we investigate structural, electronic, and vibrational properties of bulk, bilayer, and monolayer structures of h-AlN by using first-principles calculations. We show that the hexagonal phase of the bulk h-AlN is a stable direct-band-gap semiconductor. The calculated phonon spectrum displays a rigid-layer shear mode at 274 cm(-1) and an E-g mode at 703 cm(-1), which are observable by Raman measurements. In addition, single-layer h-AlN is an indirect-band-gap semiconductor with a nonmagnetic ground state. For the bilayer structure, AA'-type stacking is found to be the most favorable one, and interlayer interaction is strong. While N-layered h-AlN is an indirect-band-gap semiconductor for N = 1 – 9, we predict that thicker structures (N >= 10) have a direct band gap at the Gamma point. The number-of-layer-dependent band-gap transitions in h-AlN is interesting in that it is significantly different from the indirect-to-direct crossover obtained in the transition-metal dichalcogenides.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000350319200020 Publication Date 2015-02-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 99 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). C.B. and R.T.S. acknowledge the support from TUBITAK Project No 114F397. H.S. is supported by a FWO Pegasus Long Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:125416 Serial 1421
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Author Moldovan, D.; Peeters, F.M.
Title Strain engineering of the electronic properties of bilayer graphene quantum dots: Strain engineering of the electronic properties of bilayer graphene quantum dots Type A1 Journal article
Year (up) 2015 Publication Physica status solidi: rapid research letters Abbreviated Journal Phys Status Solidi-R
Volume 10 Issue 10 Pages 39-45
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the effect of mechanical deformations on the elec- tronic properties of hexagonal flakes of bilayer graphene. The behavior of electrons induced by triaxial strain can be de- scribed by an effective pseudo-magnetic field which is homo- geneous in the center of the flake. We find that in-plane strain, applied to both layers equally, can break the layer symmetry leading to different behavior in the top and bottom layers of graphene. At low energy, just one of the layers feels

the pseudo-magnetic field: the zero-energy pseudo-Landau level is missing in the second layer, thus creating a gap be- tween the lowest non-zero levels. While the layer asymmetry is most significant at zero energy, interaction with the edges of the flake extends the effect to higher pseudo-Landau lev- els. The behavior of the top and bottom layers may be re- versed by rotating the triaxial strain by 60°.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368814500005 Publication Date 2015-08-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6254; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.032 Times cited 9 Open Access
Notes This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. Approved Most recent IF: 3.032; 2015 IF: 2.142
Call Number c:irua:129592 Serial 3970
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Author Zhang, F.; Vanmeensel, K.; Batuk, M.; Hadermann, J.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
Title Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation Type A1 Journal article
Year (up) 2015 Publication Acta biomaterialia Abbreviated Journal Acta Biomater
Volume 16 Issue 16 Pages 215-222
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr4+, exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.10.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos 000351978600021 Publication Date 2015-02-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-7061; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited 54 Open Access
Notes Fwo G043110n Approved Most recent IF: 6.319; 2015 IF: 6.025
Call Number c:irua:124421 Serial 1473
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Author Retuerto, M.; Yin, Z.; Emge, T.J.; Stephens, P.W.; Li, M.R.; Sarkar, T.; Croft, M.C.; Ignatov, A.; Yuan, Z.; Zhang, S.J.; Jin, C.; Paria Sena, R.; Hadermann, J.; Kotliar, G.; Greenblatt, M.;
Title Hole doping and structural transformation in CsTl1-xHgxCl3 Type A1 Journal article
Year (up) 2015 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 54 Issue 54 Pages 1066-1075
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract CsTlCl3 and CsTlF3 perovskites have been theoretically predicted to be superconductors when properly hole-doped. Both compounds have been previously prepared as pure compounds: CsTlCl3 in a tetragonal (I4/m) and a cubic (Fm3̅m) perovskite polymorph and CsTlF3 as a cubic perovskite (Fm3̅m). In this work, substitution of Tl in CsTlCl3 with Hg is reported, in an attempt to hole-dope the system and induce superconductivity. The whole series CsTl1xHgxCl3 (x = 0.0, 0.1, 0.2, 0.4, 0.6, and 0.8) was prepared. CsTl0.9Hg0.1Cl3 is tetragonal as the more stable phase of CsTlCl3. However, CsTl0.8Hg0.2Cl3 is already cubic with the space group Fm3̅m and with two different positions for Tl+ and Tl3+. For x = 0.4 and 0.5, solid solutions could not be formed. For x ≥ 0.6, the samples are primitive cubic perovskites with one crystallographic position for Tl+, Tl3+, and Hg2+. All of the samples formed are insulating, and there is no signature of superconductivity. X-ray absorption spectroscopy indicates that all of the samples have a mixed-valence state of Tl+ and Tl3+. Raman spectroscopy shows the presence of the active TlClTl stretching mode over the whole series and the intensity of the TlClHg mode increases with increasing Hg content. First-principle calculations confirmed that the phases are insulators in their ground state and that Hg is not a good dopant in the search for superconductivity in this system.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000348887400048 Publication Date 2014-12-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 5 Open Access
Notes Approved Most recent IF: 4.857; 2015 IF: 4.762
Call Number c:irua:124420 Serial 1476
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Author Krause, F.F.; Ahl, J.P.; Tytko, D.; Choi, P.P.; Egoavil, R.; Schowalter, M.; Mehrtens, T.; Müller-Caspary, K.; Verbeeck, J.; Raabe, D.; Hertkorn, J.; Engl, K.; Rosenauer, A.
Title Homogeneity and composition of AlInGaN : a multiprobe nanostructure study Type A1 Journal article
Year (up) 2015 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 156 Issue 156 Pages 29-36
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The electronic properties of quaternary AlInGaN devices significantly depend on the homogeneity of the alloy. The identification of compositional fluctuations or verification of random-alloy distribution is hence of grave importance. Here, a comprehensive multiprobe study of composition and compositional homogeneity is presented, investigating AlInGaN layers with indium concentrations ranging from 0 to 17 at% and aluminium concentrations between 0 and 39 at% employing high-angle annular dark field scanning electron microscopy (HAADF STEM), energy dispersive X-ray spectroscopy (EDX) and atom probe tomography (APT). EDX mappings reveal distributions of local concentrations which are in good agreement with random alloy atomic distributions. This was hence investigated with HAADF STEM by comparison with theoretical random alloy expectations using statistical tests. To validate the performance of these tests, HAADF STEM image simulations were carried out for the case of a random-alloy distribution of atoms and for the case of In-rich clusters with nanometer dimensions. The investigated samples, which were grown by metal-organic vapor phase epitaxy (MOVPE), were thereby found to be homogeneous on this nanometer scale. Analysis of reconstructions obtained from APT measurements yielded matching results. Though HAADF STEM only allows for the reduction of possible combinations of indium and aluminium concentrations to the proximity of isolines in the two-dimensional composition space. The observed ranges of composition are in good agreement with the EDX and APT results within the respective precisions.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000361001800006 Publication Date 2015-04-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 11 Open Access
Notes 312483 Esteem2; esteem2_ta Approved Most recent IF: 2.843; 2015 IF: 2.436
Call Number c:irua:126965 c:irua:126965UA @ admin @ c:irua:126965 Serial 1485
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Author Khosravian, N.; Bogaerts, A.; Huygh, S.; Yusupov, M.; Neyts, E.C.
Title How do plasma-generated OH radicals react with biofilm components? Insights from atomic scale simulations Type A1 Journal article
Year (up) 2015 Publication Biointerphases Abbreviated Journal Biointerphases
Volume 10 Issue 10 Pages 029501
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The application of nonthermal atmospheric pressure plasma is emerging as an alternative and efficient technique for the inactivation of bacterial biofilms. In this study, reactive molecular dynamics simulations were used to examine the reaction mechanisms of hydroxyl radicals, as key reactive oxygen plasma species in biological systems, with several organic molecules (i.e., alkane, alcohol, carboxylic acid, and amine), as prototypical components of biomolecules in the biofilm. Our results demonstrate that organic molecules containing hydroxyl and carboxyl groups may act as trapping agents for the OH radicals. Moreover, the impact of OH radicals on N-acetyl-glucosamine, as constituent component of staphylococcus epidermidis biofilms, was investigated. The results show how impacts of OH radicals lead to hydrogen abstraction and subsequent molecular damage. This study thus provides new data on the reaction mechanisms of plasma species, and particularly the OH radicals, with fundamental components of bacterial biofilms.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000357195600019 Publication Date 2014-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1934-8630;1559-4106; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.603 Times cited 10 Open Access
Notes Approved Most recent IF: 2.603; 2015 IF: 3.374
Call Number c:irua:121371 Serial 1492
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Author Milovanović, S.P.; Moldovan, D.; Peeters, F.M.
Title Veselago lensing in graphene with a p-n junction: Classical versus quantum effects Type A1 Journal article
Year (up) 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 118 Issue 118 Pages 154308
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The feasibility of Veselago lensing in graphene with a p-n junction is investigated numerically for realistic injection leads. Two different set-ups with two narrow leads are considered with absorbing or reflecting side edges. This allows us to separately determine the influence of scattering on electron focusing for the edges and the p-n interface. Both semiclassical and tight-binding simulations show a distinctive peak in the transmission probability that is attributed to the Veselago lensing effect. We investigate the robustness of this peak on the width of the injector, the position of the p-n interface, and different gate potential profiles. Furthermore, the influence of scattering by both short- and long-range impurities is considered.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000363535800022 Publication Date 2015-10-20
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 This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 2.068; 2015 IF: 2.183
Call Number c:irua:129452 Serial 3969
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Author Wende, K.; Williams, P.; Dalluge, J.; Van Gaens, W.; Aboubakr, H.; Bischof, J.; von Woedtke, T.; Goyal, S.M.; Weltmann, K.D.; Bogaerts, A.; Masur, K.; Bruggeman, P.J.;
Title Identification of the biologically active liquid chemistry induced by a nonthermal atmospheric pressure plasma jet Type A1 Journal article
Year (up) 2015 Publication Biointerphases Abbreviated Journal Biointerphases
Volume 10 Issue 10 Pages 029518
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The mechanism of interaction of cold nonequilibrium plasma jets with mammalian cells in physiologic liquid is reported. The major biological active species produced by an argon RF plasma jet responsible for cell viability reduction are analyzed by experimental results obtained through physical, biological, and chemical diagnostics. This is complemented with chemical kinetics modeling of the plasma source to assess the dominant reactive gas phase species. Different plasma chemistries are obtained by changing the feed gas composition of the cold argon based RF plasma jet from argon, humidified argon (0.27%), to argon/oxygen (1%) and argon/air (1%) at constant power. A minimal consensus physiologic liquid was used, providing isotonic and isohydric conditions and nutrients but is devoid of scavengers or serum constituents. While argon and humidified argon plasma led to the creation of hydrogen peroxide dominated action on the mammalian cells, argonoxygen and argonair plasma created a very different biological action and was characterized by trace amounts of hydrogen peroxide only. In particular, for the argonoxygen (1%), the authors observed a strong negative effect on mammalian cell proliferation and metabolism. This effect was distance dependent and showed a half life time of 30 min in a scavenger free physiologic buffer. Neither catalase and mannitol nor superoxide dismutase could rescue the cell proliferation rate. The strong distance dependency of the effect as well as the low water solubility rules out a major role for ozone and singlet oxygen but suggests a dominant role of atomic oxygen. Experimental results suggest that O reacts with chloride, yielding Cl2 − or ClO−. These chlorine species have a limited lifetime under physiologic conditions and therefore show a strong time dependent biological activity. The outcomes are compared with an argon MHz plasma jet (kinpen) to assess the differences between these (at least seemingly) similar plasma sources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000357195600036 Publication Date 2015-05-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1934-8630;1559-4106; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.603 Times cited 137 Open Access
Notes Approved Most recent IF: 2.603; 2015 IF: 3.374
Call Number c:irua:126774 Serial 1549
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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 (up) 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 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 Yusupov, M.; Neyts, E.C.; Verlackt, C.C.; Khalilov, U.; van Duin, A.C.T.; Bogaerts, A.
Title Inactivation of the endotoxic biomolecule lipid A by oxygen plasma species : a reactive molecular dynamics study Type A1 Journal article
Year (up) 2015 Publication Plasma processes and polymers Abbreviated Journal Plasma Process Polym
Volume 12 Issue 12 Pages 162-171
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Reactive molecular dynamics simulations are performed to study the interaction of reactive oxygen species, such as OH, HO2 and H2O2, with the endotoxic biomolecule lipid A of the gram-negative bacterium Escherichia coli. It is found that the aforementioned plasma species can destroy the lipid A, which consequently results in reducing its toxic activity. All bond dissociation events are initiated by hydrogen-abstraction reactions. However, the mechanisms behind these dissociations are dependent on the impinging plasma species, i.e. a clear difference is observed in the mechanisms upon impact of HO2 radicals and H2O2 molecules on one hand and OH radicals on the other hand. Our simulation results are in good agreement with experimental observations.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000350275400005 Publication Date 2014-09-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1612-8850; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.846 Times cited 18 Open Access
Notes Approved Most recent IF: 2.846; 2015 IF: 2.453
Call Number c:irua:123540 Serial 1589
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Author Kelchtermans, A.; Adriaensens, P.; Slocombe, D.; Kuznetsov, V.L.; Hadermann, J.; Riskin, A.; Elen, K.; Edwards, P.P.; Hardy, A.; Van Bael, M.K.
Title Increasing the solubility limit for tetrahedral aluminium in ZnO:Al nanorods by variation in synthesis parameters Type A1 Journal article
Year (up) 2015 Publication Journal of nanomaterials Abbreviated Journal J Nanomater
Volume 2015 Issue 2015 Pages 1-8
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanocrystalline ZnO:Al nanoparticles are suitable building blocks for transparent conductive layers. As the concentration of substitutional tetrahedral Al is an important factor for improving conductivity, here we aim to increase the fraction of substitutional Al. To this end, synthesis parameters of a solvothermal reaction yielding ZnO:Al nanorods were varied. A unique set of complementary techniques was combined to reveal the exact position of the aluminium ions in the ZnO lattice and demonstrated its importance in order to evaluate the potential of ZnO:Al nanocrystals as optimal building blocks for solution deposited transparent conductive oxide layers. Both an extension of the solvothermal reaction time and stirring during solvothermal treatment result in a higher total tetrahedral aluminium content in the ZnO lattice. However, only the longer solvothermal treatment effectively results in an increase of the substitutional positions aimed for.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000358516300001 Publication Date 2015-07-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1687-4110;1687-4129; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.871 Times cited 2 Open Access
Notes FWO; Methusalem Approved Most recent IF: 1.871; 2015 IF: 1.644
Call Number c:irua:124426 Serial 1600
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Author Van Boxem, R.; Partoens, B.; Verbeeck, J.
Title Inelastic electron-vortex-beam scattering Type A1 Journal article
Year (up) 2015 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
Volume 91 Issue 91 Pages 032703
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Recent theoretical and experimental developments in the field of electron-vortex-beam physics have raised questions about what exactly this novelty in the field of electron microscopy (and other fields, such as particle physics) really provides. An important part of the answer to these questions lies in scattering theory. The present investigation explores various aspects of inelastic quantum scattering theory for cylindrically symmetric beams with orbital angular momentum. The model system of Coulomb scattering on a hydrogen atom provides the setting to address various open questions: How is momentum transferred? Do vortex beams selectively excite atoms, and how can one employ vortex beams to detect magnetic transitions? The analytical approach presented here provides answers to these questions. OAM transfer is possible, but not through selective excitation; rather, by pre- and postselection one can filter out the relevant contributions to a specific signal.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000351035000004 Publication Date 2015-03-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.925 Times cited 31 Open Access
Notes Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra3 ECASJO; Approved Most recent IF: 2.925; 2015 IF: 2.808
Call Number c:irua:123925 c:irua:123925UA @ admin @ c:irua:123925 Serial 1607
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Author Dumpala, S.; Broderick, S.R.; Khalilov, U.; Neyts, E.C.; van Duin, A.C.T.; Provine, J.; Howe, R.T.; Rajan, K.
Title Integrated atomistic chemical imaging and reactive force field molecular dynamic simulations on silicon oxidation Type A1 Journal article
Year (up) 2015 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 106 Issue 106 Pages 011602
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this paper, we quantitatively investigate with atom probe tomography, the effect of temperature on the interfacial transition layer suboxide species due to the thermal oxidation of silicon. The chemistry at the interface was measured with atomic scale resolution, and the changes in chemistry and intermixing at the interface were identified on a nanometer scale. We find an increase of suboxide (SiOx) concentration relative to SiO2 and increased oxygen ingress with elevated temperatures. Our experimental findings are in agreement with reactive force field molecular dynamics simulations. This work demonstrates the direct comparison between atom probe derived chemical profiles and atomistic-scale simulations for transitional interfacial layer of suboxides as a function of temperature.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000347976900008 Publication Date 2015-01-06
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 19 Open Access
Notes Approved Most recent IF: 3.411; 2015 IF: 3.302
Call Number c:irua:122300 Serial 1679
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Author Sentosun, K.; Sanz Ortiz, M.N.; Batenburg, K.J.; Liz-Marzán, L.M.; Bals, S.
Title Combination of HAADF-STEM and ADF-STEM Tomography for Core-Shell Hybrid Materials Type A1 Journal article
Year (up) 2015 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char
Volume 32 Issue 32 Pages 1063-1067
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Vision lab
Abstract Characterization of core-shell type nanoparticles in 3D by transmission electron microscopy (TEM) can be very challenging. Especially when both heavy and light elements co-exist within the same nanostructure, artefacts in the 3D reconstruction are often present. A representative example would be a particle comprising an anisotropic metallic (Au) nanoparticle coated with a (mesoporous) silica shell. To obtain a reliable 3D characterization of such an object, we propose a dose-efficient strategy to simultaneously acquire high angle annular dark field scanning TEM and annular dark field tilt series for tomography. The 3D reconstruction is further improved by applying an advanced masking and interpolation approach to the acquired data. This new methodology enables us to obtain high quality reconstructions from which also quantitative information can be extracted. This approach is broadly applicable to investigate hybrid core-shell materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368446800003 Publication Date 2015-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0934-0866; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.474 Times cited 13 Open Access OpenAccess
Notes S.B. acknowledges financial support from European Research Council (ERC) (ERC Starting Grant #335078-COLOURATOM). L.M. acknowledges funding from the EU, Grant# 310651-2 Self-Assembly in Confined Space (SACS). K.J.B acknowledges financial support from the Netherlands Organisation for Scientific Research (NWO), project number 639.072.005 and NWO CW 700.57.026. Networking support was provided by COST Action MP1207. The authors acknowledge the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 for financial support.; esteem2jra4; ECASSara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 4.474; 2015 IF: 3.081
Call Number c:irua:129590 c:irua:129590 Serial 3967
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Author Conings, B.; Drijkoningen, J.; Gauquelin, N.; Babayigit, A.; D'Haen, J.; D'Olieslaeger, L.; Ethirajan, A.; Verbeeck, J.; Manca, J.; Mosconi, E.; Angelis, F.D.; Boyen, H.G.;
Title Intrinsic thermal instability of methylammonium lead trihalide perovskite Type A1 Journal article
Year (up) 2015 Publication Laser physics review Abbreviated Journal Adv Energy Mater
Volume 5 Issue 5 Pages 1500477
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Organolead halide perovskites currently are the new front-runners as light absorbers in hybrid solar cells, as they combine efficiencies passing already 20% with deposition temperatures below 100 °C and cheap solution-based fabrication routes. Long-term stability remains a major obstacle for application on an industrial scale. Here, it is demonstrated that significant decomposition effects already occur during annealing of a methylammonium lead triiode perovskite at 85 °C even in inert atmosphere thus violating international standards. The observed behavior supports the view of currently used perovskite materials as soft matter systems with low formation energies, thus representing a major bottleneck for their application, especially in countries with high average temperatures. This result can trigger a broader search for new perovskite families with improved thermal stability.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos 000359374900005 Publication Date 2015-06-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1614-6832; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 16.721 Times cited 1691 Open Access
Notes FWO G004413N; GOA Solarpaint Approved Most recent IF: 16.721; 2015 IF: 16.146
Call Number c:irua:127298UA @ admin @ c:irua:127298 Serial 1719
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Author Brammertz, G.; Oueslati, S.; Buffiere, M.; Bekaert, J.; El Anzeery, H.; Messaoud, K.B.; Sahayaraj, S.; Nuytten, T.; Koble, C.; Meuris, M.; Poortmans, J.;
Title Investigation of properties limiting efficiency in Cu2ZnSnSe4-based solar cells Type A1 Journal article
Year (up) 2015 Publication IEEE journal of photovoltaics Abbreviated Journal Ieee J Photovolt
Volume 5 Issue 5 Pages 649-655
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We have investigated different nonidealities in Cu2ZnSnSe4CdSZnO solar cells with 9.7% conversion efficiency, in order to determine what is limiting the efficiency of these devices. Several nonidealities could be observed. A barrier of about 300 meV is present for electron flow at the absorberbuffer heterojunction leading to a strong crossover behavior between dark and illuminated currentvoltage curves. In addition, a barrier of about 130 meV is present at the Moabsorber contact, which could be reduced to 15 meV by inclusion of a TiN interlayer. Admittance spectroscopy results on the devices with the TiN backside contact show a defect level with an activation energy of 170 meV. Using all parameters extracted by the different characterization methods for simulations of the two-diode model including injection and recombination currents, we come to the conclusion that our devices are limited by the large recombination current in the depletion region. Potential fluctuations are present in the devices as well, but they do not seem to have a special degrading effect on the devices, besides a probable reduction in minority carrier lifetime through enhanced recombination through the band tail defects.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000353524800026 Publication Date 2014-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2156-3381;2156-3403; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.712 Times cited 13 Open Access
Notes ; ; Approved Most recent IF: 3.712; 2015 IF: 3.165
Call Number c:irua:123717 Serial 1734
Permanent link to this record
 

 
Author van Oeffelen, L.; Van Roy, W.; Idrissi, H.; Charlier, D.; Lagae, L.; Borghs, G.
Title Ion current rectification, limiting and overlimiting conductances in nanopores Type A1 Journal article
Year (up) 2015 Publication PLoS ONE Abbreviated Journal Plos One
Volume 10 Issue 10 Pages e0124171
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Previous reports on Poisson-Nernst-Planck (PNP) simulations of solid-state nanopores have focused on steady state behaviour under simplified boundary conditions. These are Neumann boundary conditions for the voltage at the pore walls, and in some cases also Donnan equilibrium boundary conditions for concentrations and voltages at both entrances of the nanopore. In this paper, we report time-dependent and steady state PNP simulations under less restrictive boundary conditions, including Neumann boundary conditions applied throughout the membrane relatively far away from the nanopore. We simulated ion currents through cylindrical and conical nanopores with several surface charge configurations, studying the spatial and temporal dependence of the currents contributed by each ion species. This revealed that, due to slow co-diffusion of oppositely charged ions, steady state is generally not reached in simulations or in practice. Furthermore, it is shown that ion concentration polarization is responsible for the observed limiting conductances and ion current rectification in nanopores with asymmetric surface charges or shapes. Hence, after more than a decade of collective research attempting to understand the nature of ion current rectification in solid-state nanopores, a relatively intuitive model is retrieved. Moreover, we measured and simulated current-voltage characteristics of rectifying silicon nitride nanopores presenting overlimiting conductances. The similarity between measurement and simulation shows that overlimiting conductances can result from the increased conductance of the electric double-layer at the membrane surface at the depletion side due to voltage-induced polarization charges.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000354916100012 Publication Date 2015-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 11 Open Access
Notes Approved Most recent IF: 2.806; 2015 IF: 3.234
Call Number c:irua:126366 Serial 1744
Permanent link to this record
 

 
Author Buffière, M.; Brammertz, G.; Sahayaraj, S.; Batuk, M.; Khelifi, S.; Mangin, D.; El Mel, A.A.; Arzel, L.; Hadermann, J.; Meuris, M.; Poortmans, J.;
Title KCN chemical etch for interface engineering in Cu2ZnSnSe4 solar cells Type A1 Journal article
Year (up) 2015 Publication ACS applied materials and interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 7 Issue 7 Pages 14690-14698
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The removal of secondary phases from the surface of the kesterite crystals is one of the major challenges to improve the performances of Cu2ZnSn(S,Se)(4) (CZTSSe) thin film solar cells. In this Contribution, the KCN/KOH Chemical etching approach, originally developed for the removal of CuxSe phases in Cu(In,Ga)(S,Se)(2) thin films) is applied to CZTSe absorbers exhibiting various chemical compositions. Two distinct electrical behaviors were observed on CZTSe/CdS solar cells after treatment: (i) the improvement of the fill factor (FF) after 30 s of etching for the CZTSe absorbers showing initially a distortion of the electrical characteristic; (ii) the progressive degradation Of the FF after long treatment time for all Cu-poor CZTSe solar cell samples. The first effect can be attributed to the action of KCN on the absorber, that is found to clean the absorber free surface from most of the secondary phases surrounding the kesterite grains (e.g., Se-0, CuxSe, SnSex, SnO2, Cu2SnSe3 phases, excepting the ZnSe-based phases). The second observation was identified as a consequence of the preferential etching of Se, Sn, and Zn from the CZTSe surface by the KOH solution, combined with the modification of the alkali content of the absorber. The formation of a Cu-rich shell at the absorber/buffer layer interface, leading to the increase of the recombination rate at the interface, and the increase in the doping of the absorber layer after etching are found to be at the origin of the deterioration of the FF of the solar cells.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000358395200019 Publication Date 2015-06-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244;1944-8252; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited 34 Open Access
Notes Approved Most recent IF: 7.504; 2015 IF: 6.723
Call Number c:irua:127153 Serial 1755
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Author Kato, T.; Neyts, E.C.; Abiko, Y.; Akama, T.; Hatakeyama, R.; Kaneko, T.
Title Kinetics of energy selective Cs encapsulation in single-walled carbon nanotubes for damage-free and position-selective doping Type A1 Journal article
Year (up) 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 119 Issue 119 Pages 11903-11908
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A method has been developed for damage-free cesium (Cs) encapsulation within single-walled carbon nanotubes (SWNTs) with fine position selectivity. Precise energy tuning of Cs-ion irradiation revealed that there is a clear energy window (2060 eV) for the efficient encapsulation of Cs through the hexagonal network of SWNT sidewalls without causing significant damage. This minimum energy threshold of Cs-ion encapsulation (∼20 eV) matches well with the value obtained by ab initio simulation (∼22 eV). Furthermore, position-selective Cs encapsulation was carried out, resulting in the successful formation of pn-junction SWNT thin films with excellent environmental stability.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000355495600072 Publication Date 2015-05-06
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 3 Open Access
Notes Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:125928 Serial 1760
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