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Author Tarasov, A.; Hu, Z.-Y.; Meledina, M.; Trusov, G.; Goodilin, E.; Van Tendeloo, G.; Dobrovolsky, Y.
  Title One-Step Microheterogeneous Formation of Rutile@Anatase Core–Shell Nanostructured Microspheres Discovered by Precise Phase Mapping Type A1 Journal article
  Year 2017 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
  Volume 121 Issue 121 Pages 4443-4450
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Nanostructured core−shell microspheres with a rough rutile core and a thin anatase shell are synthesized via a one-step heterogeneous templated hydrolysis process of TiCl4 vapor on the aerosol water−air interface. The rutile-in-anatase core−shell structure has been evidenced by different electron microscopy techniques, including electron energy-loss spectroscopy and 3D electron tomography. A new mechanism for the formation of a crystalline rutile core inside the anatase shell is proposed based on a statistical evaluation of a large number of electron microscopy data. We found that the control over the TiCl4 vapor pressure, the ratio between TiCl4 and H2O aerosol, and the reaction conditions plays a crucial role in the formation of the core−shell morphology and increases the yield of nanostructured microspheres.
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  Corporate Author Thesis
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  Language Wos 000395616200038 Publication Date 2017-03-02
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.536 Times cited 4 Open Access OpenAccess
  Notes (down) Z.-Y.H., M. M., and G.V.T. acknowledge support from the the EC Framework 7 program ESTEEM2 (Reference 312483). Approved Most recent IF: 4.536
  Call Number EMAT @ emat @ c:irua:141720 Serial 4472
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Author Ni, S.; Houwman, E.; Gauquelin, N.; Chezganov, D.; Van Aert, S.; Verbeeck, J.; Rijnders, G.; Koster, G.
  Title Stabilizing perovskite Pb(Mg0.33Nb0.67)O3-PbTiO3 thin films by fast deposition and tensile mismatched growth template Type A1 Journal article
  Year 2024 Publication ACS applied materials and interfaces Abbreviated Journal
  Volume 16 Issue 10 Pages 12744-12753
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Because of its low hysteresis, high dielectric constant, and strong piezoelectric response, Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMN-PT) thin films have attracted considerable attention for the application in PiezoMEMS, field-effect transistors, and energy harvesting and storage devices. However, it remains a great challenge to fabricate phase-pure, pyrochlore-free PMN-PT thin films. In this study, we demonstrate that a high deposition rate, combined with a tensile mismatched template layer can stabilize the perovskite phase of PMN-PT films and prevent the nucleation of passive pyrochlore phases. We observed that an accelerated deposition rate promoted mixing of the B-site cation and facilitated relaxation of the compressively strained PMN-PT on the SrTiO3 (STO) substrate in the initial growth layer, which apparently suppressed the initial formation of pyrochlore phases. By employing La-doped-BaSnO3 (LBSO) as the tensile mismatched buffer layer, 750 nm thick phase-pure perovskite PMN-PT films were synthesized. The resulting PMN-PT films exhibited excellent crystalline quality close to that of the STO substrate.
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  Language Wos 001176343700001 Publication Date 2024-02-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1944-8244 ISBN Additional Links UA library record; WoS full record
  Impact Factor 9.5 Times cited Open Access
  Notes (down) We would like to acknowledge the Netherlands Organization for Scientific Research (NWO) for the financial support of this work. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 823717-ESTEEM3. Approved Most recent IF: 9.5; 2024 IF: 7.504
  Call Number UA @ admin @ c:irua:204754 Serial 9174
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Author Liao, Z.; Huijben, M.; Zhong, Z.; Gauquelin, N.; Macke, S.; Green, R.J.; Van Aert, S.; Verbeeck, J.; Van Tendeloo, G.; Held, K.; Sawatzky, G.A.; Koster, G.; Rijnders, G.
  Title Controlled lateral anisotropy in correlated manganite heterostructures by interface-engineered oxygen octahedral coupling Type A1 Journal article
  Year 2016 Publication Nature materials Abbreviated Journal Nat Mater
  Volume 15 Issue 15 Pages 425-431
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Controlled in-plane rotation of the magnetic easy axis in manganite heterostructures by tailoring the interface oxygen network could allow the development of correlated oxide-based magnetic tunnelling junctions with non-collinear magnetization, with possible practical applications as miniaturized high-switching-speed magnetic random access memory (MRAM) devices. Here, we demonstrate how to manipulate magnetic and electronic anisotropic properties in manganite heterostructures by engineering the oxygen network on the unit-cell level. The strong oxygen octahedral coupling is found to transfer the octahedral rotation, present in the NdGaO3 (NGO) substrate, to the La2/3Sr1/3MnO3 (LSMO) film in the interface region. This causes an unexpected realignment of the magnetic easy axis along the short axis of the LSMO unit cell as well as the presence of a giant anisotropic transport in these ultrathin LSMO films. As a result we possess control of the lateral magnetic and electronic anisotropies by atomic-scale design of the oxygen octahedral rotation.
  Address MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
  Corporate Author Thesis
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  Language English Wos 000372591700017 Publication Date 2016-03-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1476-1122 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 39.737 Times cited 273 Open Access
  Notes (down) We would like to acknowledge Dr. Evert Houwman for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010- 246102 IFOX. J.V. and S.V.A. acknowledges funding from FWO project G.0044.13N and G. 0368.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G., S.V.A., J.V. and G.V.T. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. Z.Z. acknowledges funding from the SFB ViCoM (Austrian Science Fund project ID F4103- N13), and Calculations have been done on the Vienna Scientific Cluster (VSC).; esteem2jra2; esteem2jra3 ECASJO_; Approved Most recent IF: 39.737
  Call Number c:irua:133190 c:irua:133190UA @ admin @ c:irua:133190 Serial 4041
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Author Boschker, H.; Verbeeck, J.; Egoavil, R.; Bals, S.; Van Tendeloo, G.; Huijben, M.; Houwman, E.P.; Koster, G.; Blank, D.H.A.; Rijnders, G.
  Title Preventing the reconstruction of the polar discontinuity at oxide heterointerfaces Type A1 Journal article
  Year 2012 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
  Volume 22 Issue 11 Pages 2235-2240
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Perovskite oxide heteroepitaxy receives much attention because of the possibility to combine the diverse functionalities of perovskite oxide building blocks. A general boundary condition for the epitaxy is the presence of polar discontinuities at heterointerfaces. These polar discontinuities result in reconstructions, often creating new functionalities at the interface. However, for a significant number of materials these reconstructions are unwanted as they alter the intrinsic materials properties at the interface. Therefore, a strategy to eliminate this reconstruction of the polar discontinuity at the interfaces is required. We show that the use of compositional interface engineering can prevent the reconstruction at the La0.67Sr0.33MnO3/SrTiO3 (LSMO/STO) interface. The polar discontinuity at this interface can be removed by the insertion of a single La0.33Sr0.67O layer, resulting in improved interface magnetization and electrical conductivity.
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  Publisher Place of Publication Weinheim Editor
  Language Wos 000304749600002 Publication Date 2012-03-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1616-301X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 72 Open Access
  Notes (down) We wish to acknowledge the financial support of the Dutch Science Foundation (NWO) and the Dutch Nanotechnology program NanoNed. S. B. acknowledges the financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. J. V. and G. V. T. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC grant N246791 – COUNTATOMS. R. E. acknowledges funding by the European Union Council under the 7th Framework Program (FP7) grant NNMP3-LA-2010-246102 IFOX. We thank Sandra Van Aert for stimulating discussions. Approved Most recent IF: 12.124; 2012 IF: 9.765
  Call Number UA @ lucian @ c:irua:98907UA @ admin @ c:irua:98907 Serial 2712
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Author Benetti, G.; Cavaliere, E.; Canteri, A.; Landini, G.; Rossolini, G.M.; Pallecchi, L.; Chiodi, M.; Van Bael, M.J.; Winckelmans, N.; Bals, S.; Gavioli, L.
  Title Direct synthesis of antimicrobial coatings based on tailored bi-elemental nanoparticles Type A1 Journal article
  Year 2017 Publication APL materials Abbreviated Journal Apl Mater
  Volume 5 Issue 5 Pages 036105
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Ultrathin coatings based on bi-elemental nanoparticles (NPs) are very promising to limit the surface-related spread of bacterial pathogens, particularly in nosocomial environments. However, tailoring the synthesis, composition, adhesion to substrate, and antimicrobial spectrum of the coating is an open challenge. Herein, we report on a radically new nanostructured coating, obtained by a one-step gas-phase deposition technique, and composed of bi-elemental Janus type Ag/Ti NPs. The NPs are characterized by a cluster-in-cluster mixing phase with metallic Ag nano-crystals embedded in amorphous TiO2 and present a promising antimicrobial activity including also multidrug resistant strains. We demonstrate the flexibility of the method to tune the embedded Ag nano-crystals dimension, the total relative composition of the coating, and the substrate type, opening the possibility of tailoring the dimension, composition, antimicrobial spectrum, and other physical/chemical properties of such multi-elemental systems. This work is expected to significantly spread the range of applications of NPs coatings, not only as an effective tool in the prevention of healthcare-associated infections but also in other technologically relevant fields like sensors or nano-/micro joining.
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  Language Wos 000398951000014 Publication Date 2017-03-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2166-532X ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.335 Times cited 21 Open Access OpenAccess
  Notes (down) We thank Urs Gfeller for the XRF measurements, Francesco Banfi for valuable discussions on the manuscript and Giulio Viano for his valuable support in the microbiological analysis. The authors acknowledge the financial support of Universita Cattolica del Sacro Cuore through D.2.2 and D.3.1 grants and from the European Union through the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). REFERENCES Approved Most recent IF: 4.335
  Call Number EMAT @ emat @ c:irua:141723UA @ admin @ c:irua:141723 Serial 4479
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Author Abakumov, A.M.; Li, C.; Boev, A.; Aksyonov, D.A.; Savina, A.A.; Abakumova, T.A.; Van Tendeloo, G.; Bals, S.
  Title Grain boundaries as a diffusion-limiting factor in lithium-rich NMC cathodes for high-energy lithium-ion batteries Type A1 Journal article
  Year 2021 Publication ACS applied energy materials Abbreviated Journal
  Volume 4 Issue 7 Pages 6777-6786
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract High-energy lithium-rich layered transition metal oxides are capable of delivering record electrochemical capacity and energy density as positive electrodes for Li-ion batteries. Their electrochemical behavior is extremely complex due to sophisticated interplay between crystal structure, electronic structure, and defect structure. Here we unravel an extra level of this complexity by revealing that the most typical representative Li1.2Ni0.13Mn0.54Co0.13O2 material, prepared by a conventional coprecipitation technique with Na2CO3 as a precipitating agent, contains abundant coherent (001) grain boundaries with a Na-enriched P2-structured block due to segregation of the residual sodium traces. The trigonal prismatic oxygen coordination of Na triggers multiple nanoscale twinning, giving rise to incoherent (104) boundaries. The cationic layers at the (001) grain boundaries are filled with transition metal cations being Mn-depleted and Co-enriched; this makes them virtually not permeable for the Li+ cations, and therefore they negatively influence the Li diffusion in and out of the spherical agglomerates. These results demonstrate that besides the mechanisms intrinsic to the crystal and electronic structure of Li-rich cathodes, their rate capability might also be depreciated by peculiar microstructural aspects. Dedicated engineering of grain boundaries opens a way for improving inherently sluggish kinetics of these materials.
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  Language Wos 000678382900042 Publication Date 2021-07-02
  Series Editor Series Title Abbreviated Series Title
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  ISSN 2574-0962 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited 4 Open Access OpenAccess
  Notes (down) We thank Dr. M. V. Berekchiian (MSU) for assisting in ICPMS measurements. We acknowledge Russian Science Foundation (Grant 20-43-01012) and Research Foundation Flanders (FWO Vlaanderen, Project No. G0F1320N) for financial support. Approved Most recent IF: NA
  Call Number UA @ admin @ c:irua:180556 Serial 6841
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Author Liao, Z; , Green, R.J; Gauquelin, N; Macke, S.; Li, L.; Gonnissen, J; Sutarto, R.; Houwman, E.P.; Zhong, Z.; Van Aert, S.; Verbeeck, J.; Sawatzky, G.A.; Huijben, M.; Koster, G.; Rijnders, G.
  Title Long-Range Domain Structure and Symmetry Engineering by Interfacial Oxygen Octahedral Coupling at Heterostructure Interface Type A1 Journal article
  Year 2016 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
  Volume 26 Issue 26 Pages 6627-6634
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract In epitaxial thin film systems, the crystal structure and its symmetry deviate from the bulk counterpart due to various mechanisms such as epitaxial strain and interfacial structural coupling, which is accompanyed by a change in their properties. In perovskite materials, the crystal symmetry can be described by rotations of sixfold coordinated transition metal oxygen octahedra, which are found to be altered at interfaces. Here, it is unraveled how the local oxygen octahedral coupling at perovskite heterostructural interfaces strongly influences the domain structure and symmetry of the epitaxial films resulting in design rules to induce various structures in thin films using carefully selected combinations of substrate/buffer/film. Very interestingly it is discovered that these combinations lead to structure changes throughout the full thickness of the film. The results provide a deep insight into understanding the origin of induced structures in a perovskite heterostructure and an intelligent route to achieve unique functional properties.
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  Language Wos 000384809800010 Publication Date 2016-06-23
  Series Editor Series Title Abbreviated Series Title
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  ISSN 1616-301x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 23 Open Access
  Notes (down) We thank B. Keimer for valuable discussions. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010-246102 IFOX. J.V. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0044.13N, G.0374.13N, G.0368.15N, G.0369.15N). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G., J.G., S.V.A., J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan.; esteem2jra2; esteem2jra3; ECASJO_; Approved Most recent IF: 12.124
  Call Number EMAT @ emat @ c:irua:144663UA @ admin @ c:irua:144663 Serial 4106
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Author Shetty, S.; Sinha, S.K.; Ahmad, R.; Singh, A.K.; Van Tendeloo, G.; Ravishankar, N.
  Title Existence of Ti2+States on the Surface of Heavily Reduced SrTiO3Nanocubes Type A1 Journal article
  Year 2017 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume Issue Pages acs.chemmater.7b04113
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Using advanced electron microscopy, we demonstrate the presence of Ti2+ on the 001 surfaces of heavily reduced strontium titanate nanocubes. While high-angle annular dark field images show a clear difference between the surfaces of the unreduced and reduced samples, electron energy loss spectroscopy detects the presence of Ti2+ on the surface of the reduced cubes. Conventional reduction only leads to the formation of Ti3+ and involves the use of high temperatures. In our case, reduction is achieved at relatively lower temperatures in the solid state using sodium borohydride as the reducing agent. Our findings provide insights into the optical properties of the samples and provide a convenient method to produce highly reduced surfaces that could demonstrate a range of exotic physical phenomena
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  Language Wos 000418206600005 Publication Date 2017-11-17
  Series Editor Series Title Abbreviated Series Title
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  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 9.466 Times cited 8 Open Access OpenAccess
  Notes (down) We thank Advanced Facility for Microscopy and Microanalysis (AFMM), IISc, Bangalore for providing the TEM facility. We also thank MNCF, CeNSE, IISc for providing the XPS and FT-IR facilities. We acknowledge the help from Prof. Anshu Pandey for providing the PL facility and Mr. Ashutosh Gupta for the help with measurements. SS and NR thank DST for providing the financial support. RA and AKS acknowledge Super Computing Education and Research Center (SERC) and Materials Research Center (MRC), at IISc for providing required computational facilities. RA acknowledges the financial support from INSPIRE fellowship, AORC.Science and Engineering Research Board; Federaal Wetenschapsbeleid; Department of Science and Technology, Ministry of Science and Technology; Approved Most recent IF: 9.466
  Call Number UA @ lucian @c:irua:147191 Serial 4767
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Author Kuznetsov, A.S.; Lu, Y.-G.; Turner, S.; Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Verbeeck, J.; Baranov, A.N.; Moshchalkov, V.V.
  Title Preparation, structural and optical characterization of nanocrystalline ZnO doped with luminescent Ag-nanoclusters Type A1 Journal article
  Year 2012 Publication Optical materials express Abbreviated Journal Opt Mater Express
  Volume 2 Issue 6 Pages 723-734
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Nanocrystalline ZnO doped with Ag-nanoclusters has been synthesized by a salt solid state reaction. Three overlapping broad emission bands due to the Ag nanoclusters have been detected at about 570, 750 and 900 nm. These emission bands are excited by an energy transfer from the exciton state of the ZnO host when pumped in the wavelength range from 250 to 400 nm. The 900 nm emission band shows characteristic orbital splitting into three components pointing out that the anisotropic crystalline wurtzite host of ZnO is responsible for this feature. Heat-treatment and temperature dependence studies confirm the origin of these emission bands. An energy level diagram for the emission process and a model for Ag nanoclusters sites are suggested. The emission of nanocrystalline ZnO doped with Ag nanoclusters may be applied for white light generation, displays driven by UV light, down-convertors for solar cells and luminescent lamps.
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  Language Wos 000304953700004 Publication Date 2012-04-30
  Series Editor Series Title Abbreviated Series Title
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  ISSN 2159-3930; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.591 Times cited Open Access
  Notes (down) We are grateful to the Methusalem Funding of Flemish Government for the support of this work. Y.-G. L. and S. T. acknowledge funding from the Fund for Scientific Research Flanders (FWO) for a postdoctoral grant and under grant number G056810N. The microscope used in this study was partially financed by the Hercules Foundation. J.V. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No246791 – COUNTATOMS and ERC Starting Grant 278510 VORTEX. The authors acknowledge the guidance of Prof. G. Van Tendeloo, EMAT Antwerpen University, in transmission electron microscopy study in this work. ECASJO_; Approved Most recent IF: 2.591; 2012 IF: 2.616
  Call Number UA @ lucian @ c:irua:97709UA @ admin @ c:irua:97709 Serial 2707
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Author Mustonen, K.; Hofer, C.; Kotrusz, P.; Markevich, A.; Hulman, M.; Mangler, C.; Susi, T.; Pennycook, T.J.; Hricovini, K.; Richter, C.M.; Meyer, J.C.; Kotakoski, J.; Skákalová, V.
  Title Towards Exotic Layered Materials: 2D Cuprous Iodide Type A1 Journal article
  Year 2021 Publication Advanced materials Abbreviated Journal Adv Mater
  Volume Issue Pages 2106922
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Heterostructures composed of two-dimensional (2D) materials are already opening many new possibilities in such fields of technology as electronics and magnonics, but far more could be achieved if the number and diversity of 2D materials is increased. So far, only a few dozen 2D crystals have been extracted from materials that exhibit a layered phase in ambient conditions, omitting entirely the large number of layered materials that may exist in other temperatures and pressures. Here, we demonstrate how these structures can be stabilized in 2D van der Waals stacks under room temperature via growing them directly in graphene encapsulation by using graphene oxide as the template material. Specifically, we produce an ambient stable 2D structure of copper and iodine, a material that normally only occurs in layered form at elevated temperatures between 645 and 675 K. Our results establish a simple route to the production of more exotic phases of materials that would otherwise be difficult or impossible to stabilize for experiments in ambient.
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  Language Wos 000744012500001 Publication Date 2021-12-07
  Series Editor Series Title Abbreviated Series Title
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  ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 19.791 Times cited Open Access OpenAccess
  Notes (down) We acknowledge funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme Grant agreements No.~756277-ATMEN (A.M. and T.S.) and No.802123-HDEM (C.H. and T.J.P.). Computational resources from the Vienna Scientific Cluster (VSC) are gratefully acknowledged. V.S. was supported by the Austrian Science Fund (FWF) (project no. I2344-N36), the Slovak Research and Development Agency (APVV-16-0319), the project CEMEA of the Slovak Academy of Sciences, ITMS project code 313021T081 of the Research & Innovation Operational Programme and from the V4-Japan Joint Research Program (BGapEng). J.K. acknowledges the FWF funding within project P31605-N36 and M.H. the funding from Slovak Research and Development Agency via the APVV-15-0693 and APVV-19-0365 project grants. Danubia NanoTech s.r.o. has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101008099 (CompSafeNano project) and also thanks Mr. Kamil Bernath for his support. Approved Most recent IF: 19.791
  Call Number EMAT @ emat @c:irua:183956 Serial 6834
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Author van der Stam, W.; Gradmann, S.; Altantzis, T.; Ke, X.; Baldus, M.; Bals, S.; de Mello Donega, C.
  Title Shape Control of Colloidal Cu2-x S Polyhedral Nanocrystals by Tuning the Nucleation Rates Type A1 Journal article
  Year 2016 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 28 Issue 28 Pages 6705-6715
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Synthesis protocols for colloidal nanocrystals (NCs) with narrow size and shape distributions are of particular interest for the successful implementation of these nanocrystals into devices. Moreover, the preparation of NCs with well-defined crystal phases is of key importance. In this work, we show that Sn(IV)-thiolate complexes formed in situ strongly influence the nucleation and growth rates of colloidal Cu2-x S polyhedral NCs, thereby dictating their final size, shape, and crystal structure. This allowed us to successfully synthesize hexagonal bifrustums and hexagonal bipyramid NCs with low-chalcocite crystal structure, and hexagonal nanoplatelets with various thicknesses and aspect ratios with the djurleite crystal structure, by solely varying the concentration of Sn(IV)-additives (namely, SnBr4) in the reaction medium. Solution and solid-state 119Sn NMR measurements show that SnBr4 is converted in situ to Sn(IV)-thiolate complexes, which increase the Cu2-x S nucleation barrier without affecting the precursor conversion rates. This influences both the nucleation and growth rates in a concentration-dependent fashion and leads to a better separation between nucleation and growth. Our approach of tuning the nucleation and growth rates with in situ-generated Sn-thiolate complexes might have a more general impact due to the availability of various metal-thiolate complexes, possibly resulting in polyhedral NCs of a wide variety of metal-sulfide compositions.
  Address Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, Utrecht University , P.O. Box 80000, 3508 TA Utrecht, The Netherlands
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  Language English Wos 000384399000037 Publication Date 2016-09-02
  Series Editor Series Title Abbreviated Series Title
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  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 9.466 Times cited 27 Open Access OpenAccess
  Notes (down) W.v.d.S. and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under grant number ECHO.712.012.001. M.B. also gratefully acknowledges NWO for funding the NMR infrastructure (Middle Groot program, grant number 700.58.102). S.B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS).; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 9.466
  Call Number EMAT @ emat @ c:irua:135928 Serial 4285
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Author Albrecht, W.; Arslan Irmak, E.; Altantzis, T.; Pedrazo‐Tardajos, A.; Skorikov, A.; Deng, T.‐S.; van der Hoeven, J.E.S.; van Blaaderen, A.; Van Aert, S.; Bals, S.
  Title 3D Atomic‐Scale Dynamics of Laser‐Light‐Induced Restructuring of Nanoparticles Unraveled by Electron Tomography Type A1 Journal article
  Year 2021 Publication Advanced Materials Abbreviated Journal Adv Mater
  Volume Issue Pages 2100972
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
  Abstract Understanding light–matter interactions in nanomaterials is crucial for

optoelectronic, photonic, and plasmonic applications. Specifically, metal

nanoparticles (NPs) strongly interact with light and can undergo shape

transformations, fragmentation and ablation upon (pulsed) laser excitation.

Despite being vital for technological applications, experimental insight into

the underlying atomistic processes is still lacking due to the complexity of

such measurements. Herein, atomic resolution electron tomography is performed

on the same mesoporous-silica-coated gold nanorod, before and after

femtosecond laser irradiation, to assess the missing information. Combined

with molecular dynamics (MD) simulations based on the experimentally

determined 3D atomic-scale morphology, the complex atomistic rearrangements,

causing shape deformations and defect generation, are unraveled.

These rearrangements are simultaneously driven by surface diffusion, facet

restructuring, and strain formation, and are influenced by subtleties in the

atomic distribution at the surface.
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  Language Wos 000671662000001 Publication Date 2021-07-11
  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 8 Open Access OpenAccess
  Notes (down) W.A. and E.A.I. contributed equally to this work. The authors acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ERC Consolidator Grants No. 815128 – REALNANO and No. 770887 – PICOMETRICS), the European Union’s Seventh Framework Programme (ERC Advanced Grant No. 291667 – HierarSACol), and the European Commission (EUSMI). W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in the Horizon2020 program (Grant 797153, SOPMEN). T.-S.D. acknowledges financial support from the National Science Foundation of China (NSFC, Grant No. 61905056). The authors also acknowledge financial support by the Research Foundation Flanders (FWO Grant G.0267.18N).; sygmaSB Approved Most recent IF: 19.791
  Call Number EMAT @ emat @c:irua:179781 Serial 6805
Permanent link to this record
 

 
Author Tian, H.; Verbeeck, J.; Brück, S.; Paul, M.; Kufer, D.; Sing, M.; Claessen, R.; Van Tendeloo, G.
  Title Interface-induced modulation of charge and polarization in thin film Fe3O4 Type A1 Journal article
  Year 2014 Publication Advanced materials Abbreviated Journal Adv Mater
  Volume 26 Issue 3 Pages 461-465
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Charge and polarization modulations in Fe3O4 are controlled by taking advantage of interfacial strain effects. The feasibility of oxidation state control by strain modification is demonstrated and it is shown that this approach offers a stable configuration at room temperature. Direct evidence of how a local strain field changes the atomic coordination and introduces atomic displacements leading to polarization of Fe ions is presented.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos 000334289300011 Publication Date 2013-10-25
  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 15 Open Access
  Notes (down) Vortex; FWO; Countatoms; Hercules ECASJO_; Approved Most recent IF: 19.791; 2014 IF: 17.493
  Call Number UA @ lucian @ c:irua:112419UA @ admin @ c:irua:112419 Serial 1694
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Author Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J.
  Title Interstitial defects in the van der Waals gap of Bi2Se3 Type A1 Journal article
  Year 2019 Publication Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) Abbreviated Journal Acta Crystallogr B
  Volume 75 Issue 4 Pages 717-732
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Bi<sub>2</sub>Se<sub>3</sub>is a thermoelectric material and a topological insulator. It is slightly conducting in its bulk due to the presence of defects and by controlling the defects different physical properties can be fine tuned. However, studies of the defects in this material are often contradicting or inconclusive. Here, the defect structure of Bi<sub>2</sub>Se<sub>3</sub>is studied with a combination of techniques: high-resolution scanning transmission electron microscopy (HR-STEM), high-resolution energy-dispersive X-ray (HR-EDX) spectroscopy, precession electron diffraction tomography (PEDT), X-ray diffraction (XRD) and first-principles calculations using density functional theory (DFT). Based on these results, not only the observed defects are discussed, but also the discrepancies in results or possibilities across the techniques. STEM and EDX revealed interstitial defects with mainly Bi character in an octahedral coordination in the van der Waals gap, independent of the applied sample preparation method (focused ion beam milling or cryo-crushing). The inherent character of these defects is supported by their observation in the structure refinement of the EDT data. Moreover, the occupancy probability of the defects determined by EDT is inversely proportional to their corresponding DFT calculated formation energies. STEM also showed the migration of some atoms across and along the van der Waals gap. The kinetic barriers calculated using DFT suggest that some paths are possible at room temperature, while others are most probably beam induced.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000480512600024 Publication Date 2019-08-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2052-5206 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.032 Times cited Open Access
  Notes (down) University of Antwerp, 31445 ; Acknowledgements We thank Artem M. Abakumov for providing the original Bi2Se3 sample and are also very grateful to Christophe Vandevelde for trying repeatedly to get good single crystal X-ray diffraction data out of each of our failed attempts at making an undeformed single crystal. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. Approved Most recent IF: 2.032
  Call Number EMAT @ emat @c:irua:161847 Serial 5295
Permanent link to this record
 

 
Author Paulus, A.; Hendrickx, M.; Mayda, S.; Batuk, M.; Reekmans, G.; von Holst, M.; Elen, K.; Abakumov, A.M.; Adriaensens, P.; Lamoen, D.; Partoens, B.; Hadermann, J.; Van Bael, M.K.; Hardy, A.
  Title Understanding the Activation of Anionic Redox Chemistry in Ti4+-Substituted Li2MnO3as a Cathode Material for Li-Ion Batteries Type A1 Journal article
  Year 2023 Publication ACS applied energy materials Abbreviated Journal ACS Appl. Energy Mater.
  Volume 6 Issue 13 Pages 6956-6971
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract Layered Li-rich oxides, demonstrating both cationic and anionic redox chemistry being used as positive electrodes for Li-ion batteries,have raised interest due to their high specific discharge capacities exceeding 250 mAh/g. However, irreversible structural transformations triggered by anionic redox chemistry result in pronounced voltagefade (i.e., lowering the specific energy by a gradual decay of discharge potential) upon extended galvanostatic cycling. Activating or suppressing oxygen anionic redox through structural stabilization induced by redox-inactivecation substitution is a well-known strategy. However, less emphasishas been put on the correlation between substitution degree and theactivation/suppression of the anionic redox. In this work, Ti4+-substituted Li2MnO3 was synthesizedvia a facile solution-gel method. Ti4+ is selected as adopant as it contains no partially filled d-orbitals. Our study revealedthat the layered “honeycomb-ordered” C2/m structure is preserved when increasing the Ticontent to x = 0.2 in the Li2Mn1-x Ti (x) O-3 solidsolution, as shown by electron diffraction and aberration-correctedscanning transmission electron microscopy. Galvanostatic cycling hintsat a delayed oxygen release, due to an improved reversibility of theanionic redox, during the first 10 charge-discharge cyclesfor the x = 0.2 composition compared to the parentmaterial (x = 0), followed by pronounced oxygen redoxactivity afterward. The latter originates from a low activation energybarrier toward O-O dimer formation and Mn migration in Li2Mn0.8Ti0.2O3, as deducedfrom first-principles molecular dynamics (MD) simulations for the“charged” state. Upon lowering the Ti substitution to x = 0.05, the structural stability was drastically improvedbased on our MD analysis, stressing the importance of carefully optimizingthe substitution degree to achieve the best electrochemical performance.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 001018266700001 Publication Date 2023-07-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2574-0962 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.4 Times cited Open Access Not_Open_Access: Available from 24.12.2023
  Notes (down) Universiteit Hasselt, AUHL/15/2 – GOH3816N ; Russian Science Foundation, 20-43-01012 ; Fonds Wetenschappelijk Onderzoek, AUHL/15/2 – GOH3816N G040116N ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO Vlaanderen and the Flemish Government-department EWI. Approved Most recent IF: 6.4; 2023 IF: NA
  Call Number EMAT @ emat @c:irua:198160 Serial 8809
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Author Sevik, C.; Bekaert, J.; Petrov, M.; Milošević, M.V.
  Title High-temperature multigap superconductivity in two-dimensional metal borides Type A1 Journal article
  Year 2022 Publication Physical review materials Abbreviated Journal Phys. Rev. Materials
  Volume 6 Issue 2 Pages 024803
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000766666300003 Publication Date 2022-02-28
  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 3.4 Times cited 4 Open Access Not_Open_Access
  Notes (down) Universiteit Antwerpen; Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, COST-118F187 ; Air Force Office of Scientific Research, FA9550-19-1-7048 ; Fonds Wetenschappelijk Onderzoek; Approved Most recent IF: 3.4
  Call Number CMT @ cmt @c:irua:187126 Serial 7047
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Author Marchetti, A.; Saniz, R.; Krishnan, D.; Rabbachin, L.; Nuyts, G.; De Meyer, S.; Verbeeck, J.; Janssens, K.; Pelosi, C.; Lamoen, D.; Partoens, B.; De Wael, K.
  Title Unraveling the Role of Lattice Substitutions on the Stabilization of the Intrinsically Unstable Pb2Sb2O7Pyrochlore: Explaining the Lightfastness of Lead Pyroantimonate Artists’ Pigments Type A1 Journal article
  Year 2020 Publication Chemistry Of Materials Abbreviated Journal Chem Mater
  Volume 32 Issue 7 Pages 2863-2873
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract The pyroantimonate pigments Naples yellow and lead tin antimonate yellow are recognized as some of the most stable synthetic yellow pigments in the history of art. However, this exceptional lightfastness is in contrast with experimental evidence suggesting that this class of mixed oxides is of semiconducting nature. In this study the electronic structure and light-induced behavior of the lead pyroantimonate pigments were determined by means of a combined multifaceted analytical and computational approach (photoelectrochemical measurements, UV-vis diffuse reflectance spectroscopy, STEM-EDS, STEM-HAADF, and density functional theory calculations). The results demonstrate both the semiconducting nature and the lightfastness of these pigments. Poor optical absorption and minority carrier mobility are the main properties responsible for the observed stability. In addition, novel fundamental insights into the role played by Na atoms in the stabilization of the otherwise intrinsically unstable Pb2Sb2O7 pyrochlore were obtained.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000526394000016 Publication Date 2020-04-14
  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 8.6 Times cited 8 Open Access OpenAccess
  Notes (down) Universiteit Antwerpen; Belgian Federal Science Policy Office; Approved Most recent IF: 8.6; 2020 IF: 9.466
  Call Number EMAT @ emat @c:irua:168819 Serial 6363
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Author Vandemeulebroucke, D.; Batuk, M.; Hajizadeh, A.; Wastiaux, M.; Roussel, P.; Hadermann, J.
  Title Incommensurate Modulations and Perovskite Growth in LaxSr2–xMnO4−δAffecting Solid Oxide Fuel Cell Conductivity Type A1 Journal Article
  Year 2024 Publication Chemistry of Materials Abbreviated Journal Chem. Mater.
  Volume Issue Pages
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract Ruddlesden-Popper La????Sr2−????MnO4−???? materials are interesting symmetric solid oxide

fuel cell electrodes due to their good redox stability, mixed ionic and electronic conducting behavior and thermal expansion that matches well with common electrolytes. In reducing environments – as at a solid oxide fuel cell anode – the x = 0.5 member, i.e. La0.5Sr1.5MnO4−????, has a much higher total conductivity than compounds with a different La/Sr ratio, although all those compositions have the same K2NiF4-type I4/mmm structure. The origin for this conductivity difference is not yet known in literature. Now, a combination of in-situ and ex-situ 3D electron diffraction, high-resolution imaging, energy-dispersive X-ray analysis and electron energy-loss spectroscopy uncovered clear differences between x=0.25 and x=0.5 in the pristine structure, as well as in the transformations upon high-temperature reduction. In La0.5Sr1.5MnO4−????, Ruddlesden-Popper n=2 layer defects and an amorphous surface layer are present, but not in La0.25Sr1.75MnO4−????. After annealing at 700°C in 5% H2/Ar, La0.25Sr1.75MnO4−???? transforms to a tetragonal 2D incommensurately modulated structure with modulation vectors ⃗????1 = 0.2848(1) · (⃗????* +⃗????*) and ⃗????2 =0.2848(1) · (⃗????* – ⃗????*), whereas La0.5Sr1.5MnO4−???? only partially transforms to an orthorhombic 1D incommensurately modulated structure,

with ⃗???? = 0.318(2) · ⃗????*. Perovskite domains grow at the crystal edge at 700°C in 5%

H2 or vacuum, due to the higher La concentration on the surface compared to the bulk, which leads to a different thermodynamic equilibrium. Since it is known that a lower degree of oxygen vacancy ordering and a higher amount of perovskite blocks enhance oxygen mobility, those differences in defect structure and structural transformation upon reduction, might all contribute to the higher conductivity of La0.5Sr1.5MnO4−???? in solid oxide fuel cell anode conditions compared to other La/Sr ratios.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language English Wos 001174840900001 Publication Date 2024-02-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record
  Impact Factor 8.6 Times cited Open Access Not_Open_Access
  Notes (down) Universiteit Antwerpen, BOF TOP 38689 ; Fonds Wetenschappelijk Onderzoek, I003218N ; European Commission NanED, 956099 ; Approved Most recent IF: 8.6; 2024 IF: 9.466
  Call Number EMAT @ emat @c:irua:204354 Serial 8997
Permanent link to this record
 

 
Author Khalilov, U.; Yusupov, M.; Bogaerts, A.; Neyts, E.C.
  Title Selective Plasma Oxidation of Ultrasmall Si Nanowires Type A1 Journal article
  Year 2016 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
  Volume 120 Issue 120 Pages 472-477
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Device performance of Si|SiOx core-shell based nanowires critically depends on the exact control over the oxide thickness. Low-temperature plasma oxidation is a highly promising alternative to thermal oxidation allowing for improved control over the oxidation process, in particular for ultrasmall Si nanowires. We here elucidate the room temperature plasma oxidation mechanisms of ultrasmall Si nanowires using hybrid molecular dynamics / force-bias Monte Carlo simulations. We demonstrate how the oxidation and concurrent water formation mechanisms are a function of the oxidizing plasma species and we demonstrate how the resulting core-shell oxide thickness can be controlled through these species. A new mechanism of water formation is discussed in detail. The results provide a detailed atomic level explanation of the oxidation process of highly curved Si surfaces. These results point out a route toward plasma-based formation of ultrathin core-shell Si|SiOx nanowires at room temperature.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000368562200057 Publication Date 2015-12-21
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.536 Times cited 3 Open Access
  Notes (down) U.K. and M.Y. gratefully acknowledge financial support from the Research Foundation – Flanders (FWO), Grants 12M1315N and 1200216N. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. We thank Prof. A. C. T. van Duin for sharing the ReaxFF code. Approved Most recent IF: 4.536
  Call Number c:irua:130677 Serial 4002
Permanent link to this record
 

 
Author Heyne, M.H.; de Marneffe, J.-F.; Nuytten, T.; Meersschaut, J.; Conard, T.; Caymax, M.; Radu, I.; Delabie, A.; Neyts, E.C.; De Gendt, S.
  Title The conversion mechanism of amorphous silicon to stoichiometric WS2 Type A1 Journal article
  Year 2018 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
  Volume 6 Issue 15 Pages 4122-4130
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract The deposition of ultra-thin tungsten films and their related 2D chalcogen compounds on large area dielectric substrates by gas phase reactions is challenging. The lack of nucleation sites complicates the adsorption of W-related precursors and subsequent sulfurization usually requires high temperatures. We propose here a technique in which a thin solid amorphous silicon film is used as reductant for the gas phase precursor WF6 leading to the conversion to metallic W. The selectivity of the W conversion towards the underlying dielectric surfaces is demonstrated. The role of the Si surface preparation, the conversion temperature, and Si thickness on the formation process is investigated. Further, the in situ conversion of the metallic tungsten into thin stoichiometric WS2 is achieved by a cyclic approach based on WF6 and H2S pulses at the moderate temperature of 450 1C, which is much lower than usual oxide sulfurization processes.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000430538000036 Publication Date 2018-03-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2050-7526 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 5.256 Times cited 4 Open Access OpenAccess
  Notes (down) This work was supported throughout a strategic fundamental research grant for M. H. by the agency Flanders innovation & entrepreneurship (VLAIO). Approved Most recent IF: 5.256
  Call Number PLASMANT @ plasmant @c:irua:150968 Serial 4921
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Author Do, M.T.; Gauquelin, N.; Nguyen, M.D.; Blom, F.; Verbeeck, J.; Koster, G.; Houwman, E.P.; Rijnders, G.
  Title Interface degradation and field screening mechanism behind bipolar-cycling fatigue in ferroelectric capacitors Type A1 Journal article
  Year 2021 Publication Apl Materials Abbreviated Journal Apl Mater
  Volume 9 Issue 2 Pages 021113
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Polarization fatigue, i.e., the loss of polarization of ferroelectric capacitors upon field cycling, has been widely discussed as an interface related effect. However, mechanism(s) behind the development of fatigue have not been fully identified. Here, we study the fatigue mechanisms in Pt/PbZr0.52Ti0.48O3/SrRuO3 (Pt/PZT/SRO) capacitors in which all layers are fabricated by pulsed laser deposition without breaking the vacuum. With scanning transmission electron microscopy, we observed that in the fatigued capacitor, the Pt/PZT interface becomes structurally degraded, forming a 5 nm-10 nm thick non-ferroelectric layer of crystalline ZrO2 and diffused Pt grains. We then found that the fatigued capacitors can regain the full initial polarization switching if the externally applied field is increased to at least 10 times the switching field of the pristine capacitor. These findings suggest that polarization fatigue is driven by a two-step mechanism. First, the transient depolarization field that repeatedly appears during the domain switching under field cycling causes decomposition of the metal/ferroelectric interface, resulting in a non-ferroelectric degraded layer. Second, this interfacial non-ferroelectric layer screens the external applied field causing an increase in the coercive field beyond the usually applied maximum field and consequently suppresses the polarization switching in the cycled capacitor. Our work clearly confirms the key role of the electrode/ferroelectric interface in the endurance of ferroelectric-based devices.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000630052100006 Publication Date 2021-02-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2166-532x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.335 Times cited 5 Open Access OpenAccess
  Notes (down) This work was supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek through Grant No. F62.3.15559. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government. N.G. and J.V. acknowledge funding from the GOA project “Solarpaint” of the University of Antwerp. This work has also received funding from the European Union's Horizon 2020 research and innovation program under Grant No. 823717-ESTEEM3. We acknowledge D. Chezganov for his useful insights. Approved Most recent IF: 4.335
  Call Number UA @ admin @ c:irua:177663 Serial 6783
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Author Ding, L.; Zhao, M.; Ehlers, F.J.H.; Jia, Z.; Zhang, Z.; Weng, Y.; Schryvers, D.; Liu, Q.; Idrissi, H.
  Title “Branched” structural transformation of the L12-Al3Zr phase manipulated by Cu substitution/segregation in the Al-Cu-Zr alloy system Type A1 Journal article
  Year 2024 Publication Journal of materials science & technology Abbreviated Journal Journal of Materials Science & Technology
  Volume 185 Issue Pages 186-206
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The effect of Cu on the evolution of the Al3Zr phase in an Al-Cu-Zr cast alloy during solution treatment at 500 °C has been thoroughly studied by combining atomic resolution high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy and first-principles cal- culations. The heat treatment initially produces a pure L12-Al3Zr microstructure, allowing for about 13 % Cu to be incorporated in the dispersoid. Cu incorporation increases the energy barrier for anti-phase boundary (APB) activation, thus stabilizing the L12 structure. Additional heating leads to a Cu-induced “branched”path for the L12 structural transformation, with the latter process accelerated once the first APB has been created. Cu atoms may either (i) be repelled by the APBs, promoting the transformation to a Cu-poor D023 phase, or (ii) they may segregate at one Al-Zr layer adjacent to the APB, promoting a transformation to a new thermodynamically favored phase, Al4CuZr, formed when these segregation layers are periodically arranged. Theoretical studies suggest that the branching of the L12 transformation path is linked to the speed at which an APB is created, with Cu attraction triggered by a comparatively slow process. This unexpected transformation behavior of the L12-Al3Zr phase opens a new path to understanding, and potentially regulating the Al3Zr dispersoid evolution for high temperature applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 001154261100001 Publication Date 2023-12-24
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1005-0302 ISBN Additional Links UA library record; WoS full record
  Impact Factor 10.9 Times cited Open Access Not_Open_Access
  Notes (down) This work was supported by the National Key Research and Development Program (No. 2020YFA0405900), the National Natural Science Foundation of China (Grant No. 52371111 and U2141215 ), the Natural Science Foundation of Jiangsu Province (No. BE2022159 ). We are grateful to the High Performance Computing Center of Nanjing Tech University for supporting the computational resources. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR- FNRS). Approved Most recent IF: 10.9; 2024 IF: 2.764
  Call Number EMAT @ emat @c:irua:202392 Serial 8981
Permanent link to this record
 

 
Author Ni, B.; Mychinko, M.; Gómez‐Graña, S.; Morales‐Vidal, J.; Obelleiro‐Liz, M.; Heyvaert, W.; Vila‐Liarte, D.; Zhuo, X.; Albrecht, W.; Zheng, G.; González‐Rubio, G.; Taboada, J.M.; Obelleiro, F.; López, N.; Pérez‐Juste, J.; Pastoriza‐Santos, I.; Cölfen, H.; Bals, S.; Liz‐Marzán, L.M.
  Title Chiral Seeded Growth of Gold Nanorods Into 4‐Fold Twisted Nanoparticles with Plasmonic Optical Activity Type A1 Journal article
  Year 2022 Publication Advanced materials Abbreviated Journal Adv Mater
  Volume Issue Pages 2208299
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract A robust and reproducible methodology to prepare stable inorganic nanoparticles with chiral morphology might hold the key to the practical utilization of these materials. We describe herein an optimized chiral growth method to prepare 4-fold twisted gold nanorods, where the amino acid cysteine is used as a dissymmetry inducer. Four tilted ridges were found to develop on the surface of single-crystal nanorods upon repeated reduction of HAuCl4, in the presence of cysteine as the chiral inducer and ascorbic acid as a reducing agent. From detailed electron microscopy analysis of the crystallographic structures, we propose that dissymmetry results from the development of chiral facets in the form of protrusions (tilted ridges) on the initial nanorods, eventually leading to a twisted shape. The role of cysteine is attributed to assisting enantioselective facet evolution, which is supported by density functional theory simulations of the surface energies, modified upon adsorption of the chiral molecule. The development of R-type and S-type chiral structures (small facets, terraces, or kinks) would thus be non-equal, removing the mirror symmetry of the Au NR and in turn resulting in a markedly chiral morphology with high plasmonic optical activity.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000888886000001 Publication Date 2022-10-14
  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 29.4 Times cited 35 Open Access OpenAccess
  Notes (down) This work was supported by the MCIN/AEI/10.13039/501100011033 (Grants PID2019-108954RB-I00, PID2020-117371RA-I00, PID2020-117779RB-I00, and Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency Grant No. MDM-2017-0720), Xunta de Galicia/FEDER (Grant GRC ED431C 2020/09) and the European Regional Development Fund (ERDF). M.M., W.H. and S.B. acknowledge financial support from the European Commission under the Horizon 2020 Programme by ERC Consolidator grant no. 815128 (REALNANO). W.A. acknowledges financial support from the research program of AMOLF, which is partly financed by the Dutch Research Council (NWO). J. M.-V. and N. L. thank the Spanish Ministry of Science and Innovation for financial support (RTI2018- 101394-B-I00 and Severo Ochoa Grant MCIN/AEI/10.13039/501100011033 CEX2019-000925-S) and the Barcelona Supercomputing Center-MareNostrum (BSC-RES) for providing generous computer resources. S.G.-G. acknowledges the MCIN. B. N. acknowledges a postdoctoral fellowship of the Alexander von Humboldt Foundation. G. G.-R. acknowledges the Deutsche Forschungsgemeinschaft (GO 3526/1-1) for financial support. H.C. thanks Deutsche Forschungsgemeinschaft (DFG) SFB 1214 project B1 for funding. G.C-Z. acknowledges National Natural Science Foundation of China (Grant No. 21902148). Approved Most recent IF: 29.4
  Call Number EMAT @ emat @c:irua:191808 Serial 7115
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Author Bretos, I.; Schneller, T.; Falter, M.; Baecker, M.; Hollmann, E.; Woerdenweber, R.; Molina-Luna, L.; Van Tendeloo, G.; Eibl, O.
  Title Solution-derived YBa2Cu3O7-\delta (YBCO) superconducting films with BaZrO3 (BZO) nanodots based on reverse micelle stabilized nanoparticles Type A1 Journal article
  Year 2015 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
  Volume 3 Issue 3 Pages 3971-3979
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Superconducting YBa2Cu3O7-delta (YBCO) films with artificial BaZrO3 (BZO) nanodots were prepared using a chemical solution deposition method involving hybrid solutions composed of trifluoroacetate-based YBCO precursors and reverse micelle stabilized BZO nanoparticle dispersions. Microemulsion-mediated synthesis was used to obtain nano-sized (similar to 12 nm) and mono-dispersed BZO nanoparticles that preserve their features once introduced into the YBCO solution, as revealed by dynamic light scattering. Phase pure, epitaxial YBCO films with randomly oriented BZO nanodots distributed over their whole microstructure were grown from the hybrid solutions on (100) LaAlO3 substrates. The morphology of the YBCO-BZO nanocomposite films was strongly influenced by the amount of nanoparticles incorporated into the system, with contents ranging from 5 to 40 mol%. Scanning electron microscopy showed a high density of isolated second-phase defects consisting of BZO nanodots in the nanocomposite film with 10 mol% of BZO. Furthermore, a direct observation and quantitative analysis of lattice defects in the form of interfacial edge dislocations directly induced by the BZO nanodots was evidenced by transmission electron microscopy. The superconducting properties (77 K) of the YBCO films improved considerably by the presence of such nanodots, which seem to enhance the morphology of the sample and therefore the intergranular critical properties. The incorporation of preformed second-phase defects (here, BZO) during the growth of the superconducting phase is the main innovation of this novel approach for the all-solution based low-cost fabrication of long-length coated conductors.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000352870400018 Publication Date 2015-03-06
  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 19 Open Access
  Notes (down) This work was supported by the German Federal Ministry of Economics and Technology (BMWi) contract no. 0327433A (project ELSA). L. Molina-Luna and G. Van Tendeloo acknowledge funding from the European Research Council (ERC grant no. 24691-COUNTATOMS). The authors gratefully acknowledge J. Dornseiffer for the support with preparation of the microemulsions for the BZO nanoparticles; G. Wasse for the SEM images; and T. Po¨ssinger for the preparation of the artwork. Eurotape Approved Most recent IF: 5.256; 2015 IF: 4.696
  Call Number UA @ lucian @ c:irua:132575 Serial 4245
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Author Ignatova, K.; Vlasov, E.; Seddon, S.D.; Gauquelin, N.; Verbeeck, J.; Wermeille, D.; Bals, S.; Hase, T.P.A.; Arnalds, U.B.
  Title Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures Type A1 Journal Article
  Year 2024 Publication APL Materials Abbreviated Journal
  Volume 12 Issue 4 Pages
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract We present an investigation of the microstructure changes in V2O3 as it goes through its inherent structural phase transition. Using V2O3 films with a well-defined crystal structure deposited by reactive magnetron sputtering on r-plane Al2O3 substrates, we study the phase coexistence region and its impact on the surface roughness of the films and the magnetic properties of overlying Ni magnetic layers in V2O3/Ni hybrid magnetic heterostructures. The simultaneous presence of two phases in V2O3 during its structural phase transition was identified with high resolution x-ray diffraction and led to an increase in surface roughness observed using x-ray reflectivity. The roughness reaches its maximum at the midpoint of the transition. In V2O3/Ni hybrid heterostructures, we find a concomitant increase in the coercivity of the magnetic layer correlated with the increased roughness of the V2O3 surface. The chemical homogeneity of the V2O3 is confirmed through transmission electron microscopy analysis. High-angle annular dark field imaging and electron energy loss spectroscopy reveal an atomically flat interface between Al2O3 and V2O3, as well as a sharp interface between V2O3 and Ni.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 001202661800003 Publication Date 2024-04-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2166-532X ISBN Additional Links UA library record; WoS full record
  Impact Factor 6.1 Times cited Open Access
  Notes (down) This work was supported by the funding from the University of Iceland Research Fund, the Icelandic Research Fund Grant No. 207111. Instrumentation funding from the Icelandic Infrastructure Fund is acknowledged. This work was based on experiments per- formed at the BM28 (XMaS) beamline at the European Synchrotron Radiation Facility, Grenoble, France. XMaS is a National Research Facility funded by the UK EPSRC and managed by the Universi- ties of Liverpool and Warwick. This project has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717—ESTEEM3. Approved Most recent IF: 6.1; 2024 IF: 4.335
  Call Number EMAT @ emat @c:irua:205569 Serial 9120
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Author Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A.
  Title Influence of the Material Dielectric Constant on Plasma Generation inside Catalyst Pores Type A1 Journal article
  Year 2016 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
  Volume 120 Issue 120 Pages 25923-25934
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Plasma catalysis is gaining increasing interest for various environmental applications, but the crucial question is whether plasma can be created inside catalyst pores and under which conditions. In practice, various catalytic support materials are used, with various dielectric constants. We investigate here the influence of the dielectric constant on the plasma properties inside catalyst pores and in the sheath in front of the pores, for various pore sizes. The calculations are performed by a two-dimensional fluid model for an atmospheric pressure dielectric barrier discharge in helium. The electron impact ionization rate, electron temperature, electron and ion density, as well as the potential distribution and surface charge density, are analyzed for a better understanding of the discharge behavior inside catalyst pores. The results indicate that, in a 100 μm pore, the electron impact ionization in the pore, which is characteristic for the plasma generation inside the pore, is greatly enhanced for dielectric constants below 300. Smaller pore sizes only yield enhanced ionization for smaller dielectric constants, i.e., up to εr = 200, 150, and 50 for pore sizes of 50, 30, and 10 μm. Thus, the most common catalyst supports, i.e., Al2O3 and SiO2, which have dielectric constants around εr = 8−11 and 4.2, respectively, should allow more easily that microdischarges can be formed inside catalyst pores, even for smaller pore sizes. On the other hand, ferroelectric materials with dielectric constants above 300 never seem to yield plasma enhancement inside catalyst pores, not even for 100 μm pore sizes. Furthermore, it is clear that the dielectric constant of the material has a large effect on the extent of plasma enhancement inside the catalyst pores, especially in the range between εr = 4 and εr = 200. The obtained results are explained in detail based on the surface charge density at the pore walls,

and the potential distribution and electron temperature inside and above the pores. The results obtained with this model are

important for plasma catalysis, as the production plasma species in catalyst pores might affect the catalyst properties, and thus

improve the applications of plasma catalysis.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000388429100029 Publication Date 2016-11-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.536 Times cited 34 Open Access
  Notes (down) This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant G.0217.14N), the National Natural Science Foundation of China (Grant 11405019), and the China Postdoctoral Science Foundation (Grant 2015T80244). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the University of Antwerp. Approved Most recent IF: 4.536
  Call Number PLASMANT @ plasmant @ c:irua:138602 Serial 4319
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Author Leenaerts, O.; Vercauteren, S.; Schoeters, B.; Partoens, B.
  Title System-size dependent band alignment in lateral two-dimensional heterostructures Type A1 Journal article
  Year 2016 Publication 2D materials Abbreviated Journal 2D Mater
  Volume 3 Issue 3 Pages 025012
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The electronic band alignment in semiconductor heterostructures is a key factor for their use in electronic applications. The alignment problem has been intensively studied for bulk systems but is less well understood for low-dimensional heterostructures. In this work we investigate the alignment in two-dimensional lateral heterostructures. First-principles calculations are used to show that the electronic band offset depends crucially on the width and thickness of the heterostructure slab. The particular heterostructures under study consist of thin hydrogenated and fluorinated diamond slabs which are laterally joined together. Two different limits for the band offset are observed. For infinitely wide heterostructures the vacuum potential above the two materials is aligned leading to a large step potential within the heterostructure. For infinitely thick heterostructure slabs, on the other hand, there is no potential step in the heterostructure bulk, but a large potential step in the vacuum region above the heterojunction is observed. The band alignment in finite systems depends on the particular dimensions of the system. These observations are shown to result from an interface dipole at the heterojunction that tends to align the band structures.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000378571400032 Publication Date 2016-04-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.937 Times cited 19 Open Access
  Notes (down) 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 Hercules Foundation and the Flemish Government— department EWI. Approved Most recent IF: 6.937
  Call Number c:irua:132792 c:irua:132792 Serial 4055
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Author Aierken, Y.; Leenaerts, O.; Peeters, F.M.
  Title Defect-induced faceted blue phosphorene nanotubes Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 92 Issue 92 Pages 104104
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The properties of a new class of phosphorene nanotubes (PNT) are investigated by performing first-principles calculations. We demonstrate that it is advantageous to use blue phosphorene in order to make small nanotubes and propose a way to create low-energy PNTs by the inclusion of defect lines. Five different types of defect lines are investigated and incorporated in various combinations. The resulting defect-induced faceted PNTs have negligible bending stresses which leads to a reduction in the formation energy with respect to round PNTs. Our armchair faceted PNTs have similar formation energies than the recently proposed multiphase faceted PNTs, but they have a larger variety of possible structures. Our zigzag faceted PNTs have lower formation energies than round tubes and multiphase faceted nanotubes. The electronic properties of the defect-induced faceted PNTs are determined by the defect lines which control the band gap and the shape of the electronic states at the band edges. These band gaps increase with the radius of the nanotubes and converge to those of isolated defect lines.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000361037200006 Publication Date 2015-09-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 24 Open Access
  Notes (down) This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and ser- vices used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government, department EWI. Approved Most recent IF: 3.836; 2015 IF: 3.736
  Call Number c:irua:127837 Serial 4033
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M.
  Title Disordered graphene Josephson junctions Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 91 Issue 91 Pages 054506
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract A tight-binding approach based on the Chebyshev-Bogoliubov-de Gennes method is used to describe disordered single-layer graphene Josephson junctions. Scattering by vacancies, ripples, or charged impurities is included. We compute the Josephson current and investigate the nature of multiple Andreev reflections, which induce bound states appearing as peaks in the density of states for energies below the superconducting gap. In the presence of single-atom vacancies, we observe a strong suppression of the supercurrent, which is a consequence of strong intervalley scattering. Although lattice deformations should not induce intervalley scattering, we find that the supercurrent is still suppressed, which is due to the presence of pseudomagnetic barriers. For charged impurities, we consider two cases depending on whether the average doping is zero, i.e., existence of electron-hole puddles, or finite. In both cases, short-range impurities strongly affect the supercurrent, similar to the vacancies scenario.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000349436500001 Publication Date 2015-02-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 7 Open Access
  Notes (down) This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Methusalem funding of the Flemish Government. Approved Most recent IF: 3.836; 2015 IF: 3.736
  Call Number c:irua:129192 Serial 3961
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M.
  Title Superconducting current and proximity effect in ABA and ABC multilayer graphene Josephson junctions Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 88 Issue 88 Pages 214502
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using a numerical tight-binding approach based on the Chebyshev–Bogoliubov–de Gennes method we describe Josephson junctions made of multilayer graphene contacted by top superconducting gates. Both Bernal (ABA) and rhombohedral (ABC) stacking are considered and we find that the type of stacking has a strong effect on the proximity effect and the supercurrent flow. For both cases the pair amplitude shows a polarization between dimer and nondimer atoms, being more pronounced for rhombohedral stacking. Even though the proximity effect in nondimer sites is enhanced when compared to single-layer graphene, we find that the supercurrent is suppressed. The spatial distribution of the supercurrent shows that for Bernal stacking the current flows only in the topmost layers while for rhombohedral stacking the current flows throughout the whole structure.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000328569900004 Publication Date 2013-12-02
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 4 Open Access
  Notes (down) This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number CMT @ cmt @ c:irua:128896 Serial 3962
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