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Author | Schnepf, M.J.; Mayer, M.; Kuttner, C.; Tebbe, M.; Wolf, D.; Dulle, M.; Altantzis, T.; Formanek, P.; Förster, S.; Bals, S.; König, T.A.F.; Fery, A. | ||||
Title | Nanorattles with tailored electric field enhancement | Type | A1 Journal article | ||
Year | 2017 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 9 | Issue | 9 | Pages | 9376-9385 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanorattles are metallic core–shell particles with core and shell separated by a dielectric spacer. These nanorattles have been identified as a promising class of nanoparticles, due to their extraordinary high electric-field enhancement inside the cavity. Limiting factors are reproducibility and loss of axial symmetry owing to the movable metal core; movement of the core results in fluctuation of the nanocavity dimensions and commensurate variations in enhancement factor. We present a novel synthetic approach for the robust fixation of the central gold rod within a well-defined box, which results in an axisymmetric nanorattle. We determine the structure of the resulting axisymmetric nanorattles by advanced transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS). Optical absorption and scattering cross-sections obtained from UV-vis-NIR spectroscopy quantitatively agree with finite-difference time-domain (FDTD) simulations based on the structural model derived from SAXS. The predictions of high and homogenous field enhancement are evidenced by scanning TEM electron energy loss spectroscopy (STEM-EELS) measurement on single-particle level. Thus, comprehensive understanding of structural and optical properties is achieved for this class of nanoparticles, paving the way for photonic applications where a defined and robust unit cell is crucial. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000405387100015 | Publication Date | 2017-06-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 69 | Open Access | OpenAccess |
Notes | This study was funded by the European Research Council under grant Template-assisted assembly of METAmaterials using MECHanical instabilities (METAMECH) ERC-2012-StG 306686. This work was also supported by the Deutsche Forschungsgemeinschaft (DFG) within the Cluster of Excellence ‘Center for Advancing Electronics Dresden’ (cfaed). M. T. wants to acknowledge funding by the Elite Network of Bavaria, the Bavarian Ministry of State according to the Bavarian elite promotion act (BayEFG), as well as the Alexander von Humboldt Foundation for a Feodor-Lynen Research Fellowship. S. B. acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078) and T. A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. We thank Ken Harris from the National Research Council Canada for valuable discussion of the manuscript. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 7.367 | ||
Call Number | EMAT @ emat @ c:irua:144797UA @ admin @ c:irua:144797 | Serial | 4631 | ||
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Author | De Backer, A.; Jones, L.; Lobato, I.; Altantzis, T.; Goris, B.; Nellist, P.D.; Bals, S.; Van Aert, S. | ||||
Title | Three-dimensional atomic models from a single projection using Z-contrast imaging: verification by electron tomography and opportunities | Type | A1 Journal article | ||
Year | 2017 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 9 | Issue | 9 | Pages | 8791-8798 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In order to fully exploit structure–property relations of nanomaterials, three-dimensional (3D) characterization at the atomic scale is often required. In recent years, the resolution of electron tomography has reached the atomic scale. However, such tomography typically requires several projection images demanding substantial electron dose. A newly developed alternative circumvents this by counting the number of atoms across a single projection. These atom counts can be used to create an initial atomic model with which an energy minimization can be applied to obtain a relaxed 3D reconstruction of the nanoparticle. Here, we compare, at the atomic scale, this single projection reconstruction approach with tomography and find an excellent agreement. This new approach allows for the characterization of beam-sensitive materials or where the acquisition of a tilt series is impossible. As an example, the utility is illustrated by the 3D atomic scale characterization of a nanodumbbell on an in situ heating holder of limited tilt range. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000404614700031 | Publication Date | 2017-06-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 33 | Open Access | OpenAccess |
Notes | The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N, G.0368.15N, and WO.010.16N) and postdoctoral grants to T. Altantzis, A. De Backer, and B. Goris. S. Bals acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078). Funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiatieve-I3) is acknowledged. The authors would also like to thank Luis Liz-Marzán, Marek Grzelczak, and Ana Sánchez-Iglesias for sample provision. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 7.367 | ||
Call Number | EMAT @ emat @ c:irua:144436UA @ admin @ c:irua:144436 | Serial | 4617 | ||
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Author | Pramanik, G.; Kvakova, K.; Thottappali, M.A.; Rais, D.; Pfleger, J.; Greben, M.; El-Zoka, A.; Bals, S.; Dracinsky, M.; Valenta, J.; Cigler, P. | ||||
Title | Inverse heavy-atom effect in near infrared photoluminescent gold nanoclusters | Type | A1 Journal Article | ||
Year | 2021 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 13 | Issue | 23 | Pages | 10462-10467 |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | Fluorophores functionalized with heavy elements show enhanced intersystem crossing due to increased spin–orbit coupling, which in turn shortens the fluorescence decay lifetime (<italic>τ</italic><sup>PL</sup>). This phenomenon is known as the heavy-atom effect (HAE). Here, we report the observation of increased<italic>τ</italic><sup>PL</sup>upon functionalisation of near-infrared photoluminescent gold nanoclusters with iodine. The heavy atom-mediated increase in<italic>τ</italic><sup>PL</sup>is in striking contrast with the HAE and referred to as inverse HAE. Femtosecond and nanosecond transient absorption spectroscopy revealed overcompensation of a slight decrease in lifetime of the transition associated with the Au core (ps) by a large increase in the long-lived triplet state lifetime associated with the Au shell, which contributed to the observed inverse HAE. This unique observation of inverse HAE in gold nanoclusters provides the means to enhance the triplet excited state lifetime. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2021-05-24 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | ||
Impact Factor | 7.367 | Times cited | 7 | Open Access | OpenAccess |
Notes | The authors acknowledge support from GACR project Nr.18- 12533S. G. P. acknowledges support from EUSMI project No. E180200060; J.P. from the Ministry of Education, Youth and Sports of the Czech Republic – Program INTER-EXCELLENCE (LTAUSA19066). | Approved | Most recent IF: 7.367 | ||
Call Number | EMAT @ emat @ | Serial | 6950 | ||
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Author | Kinnear, C.; Rodriguez-Lorenzo, L.; Clift, M.J.D.; Goris, B.; Bals, S.; Rothen, B.; Fink, A.S. | ||||
Title | Decoupling the shape parameter to assess gold nanorod uptake by mammalian cells | Type | A1 Journal article | ||
Year | 2016 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 8 | Issue | 8 | Pages | 16416-16426 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The impact of nanoparticles (NPs) upon biological systems can be fundamentally associated with their physicochemical parameters. A further often-stated tenet is the importance of NP shape on rates of endocytosis. However, given the convoluted parameters concerning the NP-cell interaction, it is experimentally challenging to attribute any findings to shape alone. Herein we demonstrate that shape, below a certain limit, which is specific to nanomedicine, is not important for the endocytosis of spherocylinders by either epithelial or macrophage cells in vitro. Through a systematic approach, we reshaped a single batch of gold nanorods into different aspect ratios resulting in near-spheres and studied their cytotoxicity, (pro-)inflammatory status, and endocytosis/exocytosis. It was found that on a length scale of ~10-90 nm and at aspect ratios less than 5, NP shape has little impact upon their entry into either macrophages or epithelial cells. Conversely, nanorods with an aspect ratio above 5 were preferentially endocytosed by epithelial cells, whereas there was a lack of shape dependent uptake following exposure to macrophages in vitro. These findings have implications both in the understanding of nanoparticle reshaping mechanisms, as well as in the future rational design of nanomaterials for biomedical applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000384531600036 | Publication Date | 2016-08-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 23 | Open Access | OpenAccess |
Notes | The authors would like to thank C. Endes for her help and technical assistance with all cell culture experiments. The work was supported by the Adolphe Merkle Foundation, the Swiss National Science Foundation (PP00P2123373), the Swiss National Science Foundation through the National Centre of Competence in Research Bio-Inspired Materials, the Flemish Fund for Scientific Research (FWO Vlaanderen) through a postdoctoral research grant, and the European Research Council (ERC Starting Grant #335078-COLOURATOMS). The authors also appreciate financial support from the European Union under the Seventh Framework Program (Integrated Infrastructure Initiative N. 262348 European Soft Matter Infrastructure, ESMI).; ECASSara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); | Approved | Most recent IF: 7.367 | ||
Call Number | c:irua:135087 c:irua:135087 | Serial | 4109 | ||
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Author | Zanaga, D.; Bleichrodt, F.; Altantzis, T.; Winckelmans, N.; Palenstijn, W.J.; Sijbers, J.; de Nijs, B.; van Huis, M.A.; Sanchez-Iglesias, A.; Liz-Marzan, L.M.; van Blaaderen, A.; Joost Batenburg, K.; Bals, S.; Van Tendeloo, G. | ||||
Title | Quantitative 3D analysis of huge nanoparticle assemblies | Type | A1 Journal article | ||
Year | 2016 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 8 | Issue | 8 | Pages | 292-299 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | Nanoparticle assemblies can be investigated in 3 dimensions using electron tomography. However, it is not straightforward to obtain quantitative information such as the number of particles or their relative position. This becomes particularly difficult when the number of particles increases. We propose a novel approach in which prior information on the shape of the individual particles is exploited. It improves the quality of the reconstruction of these complex assemblies significantly. Moreover, this quantitative Sparse Sphere Reconstruction approach yields directly the number of particles and their position as an output of the reconstruction technique, enabling a detailed 3D analysis of assemblies with as many as 10 000 particles. The approach can also be used to reconstruct objects based on a very limited number of projections, which opens up possibilities to investigate beam sensitive assemblies where previous reconstructions with the available electron tomography techniques failed. | ||||
Address | EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. sara.bals@uantwerpen.be | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000366911700028 | Publication Date | 2015-11-19 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 34 | Open Access | OpenAccess |
Notes | The authors acknowledge financial support from European Research Council (ERC Starting Grant # 335078-COLOURATOMS, ERC Advanced Grant # 291667 HierarSACol and ERC Advanced Grant 267867 – PLASMAQUO), the European Union under the FP7 (Integrated Infrastructure Initiative N. 262348 European Soft Matter Infrastructure, ESMI and N. 312483 ESTEEM2), and 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.; esteem2jra4; ECASSara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); | Approved | Most recent IF: 7.367 | ||
Call Number | c:irua:131062 c:irua:131062 | Serial | 3979 | ||
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Author | Egoavil, R.; Huehn, S.; Jungbauer, M.; Gauquelin, N.; Béché, A.; Van Tendeloo, G.; Verbeeck; Moshnyaga, V. | ||||
Title | Phase problem in the B-site ordering of La2CoMnO6 : impact on structure and magnetism | Type | A1 Journal article | ||
Year | 2015 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 7 | Issue | 7 | Pages | 9835-9843 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Epitaxial double perovskite La2CoMnO6 (LCMO) films were grown by metalorganic aerosol deposition on SrTiO3(111) substrates. A high Curie temperature, T-C = 226 K, and large magnetization close to saturation, M-S(5 K) = 5.8 mu(B)/f.u., indicate a 97% degree of B-site (Co,Mn) ordering within the film. The Co/Mn ordering was directly imaged at the atomic scale by scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDX). Local electron-energy-loss spectroscopy (EELS) measurements reveal that the B-sites are predominantly occupied by Co2+ and Mn4+ ions in quantitative agreement with magnetic data. Relatively small values of the (1/2 1/2 1/2) superstructure peak intensity, obtained by X-ray diffraction (XRD), point out the existence of ordered domains with an arbitrary phase relationship across the domain boundary. The size of these domains is estimated to be in the range 35-170 nm according to TEM observations and modelling the magnetization data. These observations provide important information towards the complexity of the cation ordering phenomenon and its implications on magnetism in double perovskites, and similar materials. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000354983100060 | Publication Date | 2015-05-05 | |
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 | 37 | Open Access | |
Notes | 312483 ESTEEM2; FWO G004413N; 246102 IFOX; Hercules; esteem2_jra3 | Approved | Most recent IF: 7.367; 2015 IF: 7.394 | ||
Call Number | c:irua:126423 c:irua:126423 | Serial | 2586 | ||
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Author | Turner, S.; Idrissi, H.; Sartori, A.F.; Korneychuck, S.; Lu, Y.-G.; Verbeeck, J.; Schreck, M.; Van Tendeloo, G. | ||||
Title | Direct imaging of boron segregation at dislocations in B:diamond heteroepitaxial films | Type | A1 Journal article | ||
Year | 2016 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 8 | Issue | 8 | Pages | 2212-2218 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | A thin film of heavily B-doped diamond has been grown epitaxially by microwave plasma chemical vapor deposition on an undoped diamond layer, on top of a Ir/YSZ/Si(001) substrate stack, to study the boron segregation and boron environment at the dislocations present in the film. The density and nature of the dislocations were investigated by conventional and weak-beam dark-field transmission electron microscopy techniques, revealing the presence of two types of dislocations: edge and mixed-type 45 degrees dislocations. The presence and distribution of B in the sample was studied using annular dark-field scanning transmission electron microscopy and spatially resolved electron energy-loss spectroscopy. Using these techniques, a segregation of B at the dislocations in the film is evidenced, which is shown to be intermittent along the dislocation. A single edge-type dislocation was selected to study the distribution of the boron surrounding the dislocation core. By imaging this defect at atomic resolution, the boron is revealed to segregate towards the tensile strain field surrounding the edge-type dislocations. An investigation of the fine structure of the B-K edge at the dislocation core shows that the boron is partially substitutionally incorporated into the diamond lattice and partially present in a lower coordination (sp(2)-like hybridization). | ||||
Address | EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. stuart.turner@uantwerpen.be | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000368860900053 | Publication Date | 2015-12-21 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 15 | Open Access | |
Notes | S. T. acknowledges the fund for scien tific research Flanders (FWO) for a post-doctoral scholarship and under contract number G.0044.13N | Approved | Most recent IF: 7.367 | ||
Call Number | c:irua:131597UA @ admin @ c:irua:131597 | Serial | 4121 | ||
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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 | 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); | ||||
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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 | 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. | ||||
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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 | Chen, J.-J.; Ke, X.; Van Tendeloo, G.; Meng, J.; Zhou, Y.-B.; Liao, Z.-M.; Yu, D.-P. | ||||
Title | Magnetotransport across the metal-graphene hybrid interface and its modulation by gate voltage | Type | A1 Journal article | ||
Year | 2015 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 7 | Issue | 7 | Pages | 5516-5524 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The graphene-metal contact is very important for optimizing the performance of graphene based electronic devices. However, it is difficult to probe the properties of the graphene/metal interface directly via transport measurements in traditional graphene lateral devices, because the dominated transport channel is graphene, not the interface. Here, we employ the Au/graphene/Au vertical and lateral hybrid structure to unveil the metal-graphene interface properties, where the transport is dominated by the charge carriers across the interface. The magnetoresistance (MR) of Au/monolayer graphene/Au and Au/stacked two-layered graphene/Au devices is measured and modulated by gate voltage, demonstrating that the interface is a device. The gate-tunable MR is identified from the graphene lying on the SiO2 substrate and underneath the top metal electrode. Our unique structures couple the in-plane and out-of-plane transport and display linear MR with small amplitude oscillations at low temperatures. Under a magnetic field, the electronic coupling between the graphene edge states and the electrode leads to the appearance of quantum oscillations. Our results not only provide a new pathway to explore the intrinsic transport mechanism at the graphene/metal interface but also open up new vistas of magnetoelectronics. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000351372400050 | Publication Date | 2015-02-19 | |
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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 | 3 | Open Access | |
Notes | 246791 Countatoms | Approved | Most recent IF: 7.367; 2015 IF: 7.394 | ||
Call Number | c:irua:125533 | Serial | 1931 | ||
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Author | Meledina, M.; Turner, S.; Galvita, V.V.; Poelman, H.; Marin, G.B.; Van Tendeloo, G. | ||||
Title | Local environment of Fe dopants in nanoscale Fe : CeO2-x oxygen storage material | Type | A1 Journal article | ||
Year | 2015 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 7 | Issue | 7 | Pages | 3196-3204 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanoscale Fe : CeO2-x oxygen storage material for the process of chemical looping has been investigated by advanced transmission electron microscopy and electron energy-loss spectroscopy before and after a model looping procedure, consisting of redox cycles at heightened temperature. Separately, the activity of the nanomaterial has been tested in a toluene total oxidation reaction. The results show that the material consists of ceria nanoparticles, doped with single Fe atoms and small FeOx clusters. The iron ion is partially present as Fe3+ in a solid solution within the ceria lattice. Furthermore, enrichment of reduced Fe2+ species is observed in nanovoids present in the ceria nanoparticles, as well as at the ceria surface. After chemical looping, agglomeration occurs and reduced nanoclusters appear at ceria grain boundaries formed by sintering. These clusters originate from surface Fe2+ aggregation, and from bulk Fe3+, which “leaks out” in reduced state after cycling to a slightly more agglomerated form. The activity of Fe : CeO2 during the toluene total oxidation part of the chemical looping cycle is ensured by the dopant Fe in the Fe1-xCexO2 solid solution, and by surface Fe species. These measurements on a model Fe : CeO2-x oxygen storage material give a unique insight into the behavior of dopants within a nanosized ceria host, and allow to interpret a plethora of (doped) cerium oxide-based reactions. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000349473200046 | Publication Date | 2015-01-13 | |
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 | 17 | Open Access | |
Notes | Approved | Most recent IF: 7.367; 2015 IF: 7.394 | |||
Call Number | c:irua:125299 | Serial | 1828 | ||
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