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Author Vereecke, B.; van der Veen, M.H.; Sugiura, M.; Kashiwagi, Y.; Ke, X.; Cott, D.J.; Hantschel, T.; Huyghebaert, C.; Tökei, Z.
Title Wafer-level electrical evaluation of vertical carbon nanotube bundles as a function of growth temperature Type A1 Journal article
Year 2013 Publication Japanese journal of applied physics Abbreviated Journal Jpn J Appl Phys
Volume 52 Issue 42 Pages 04cn02-5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have evaluated the resistance of carbon nanotubes (CNTs) grown at a CMOS-compatible temperature using a realistic integration scheme. The structural analysis of the CNTs by transmission electron microscopy (TEM) showed that the degree of graphitization decreased significantly when the growth temperature was decreased from 540 to 400 °C. The CNTs were integrated to form 150-nm-diameter vertical interconnects between a TiN layer and Cu metal trenches on 200 mm full wafers. Wafers with CNTs grown at low temperature were found to have a lower single-contact resistance than those produced at high temperatures. Thickness measurements showed that the low contact resistance is a result of small contact height. This height dependence is masking the impact of CNT graphitization quality on resistance. When benchmarking our results with data from the literature, a relationship between resistivity and growth temperature cannot be found for CNT-based vertical interconnects.
Address
Corporate Author Thesis
Publisher Place of Publication Kyoto Editor
Language Wos 000320002400150 Publication Date 2013-03-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-4922;1347-4065; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.384 Times cited 5 Open Access
Notes Approved (up) Most recent IF: 1.384; 2013 IF: 1.057
Call Number UA @ lucian @ c:irua:108713 Serial 3902
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Author Bittencourt, C.; Hecq, M.; Felten, A.; Pireaux, J.J.; Ghijsen, J.; Felicissimo, M.P.; Rudolf, P.; Drube, W.; Ke, X.; Van Tendeloo, G.
Title Platinumcarbon nanotube interaction Type A1 Journal article
Year 2008 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 462 Issue 4/6 Pages 260-264
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The interaction between evaporated Pt and pristine or oxygen-plasma-treated multiwall carbon nanotubes (CNTs) is investigated. Pt is found to nucleate at defect sites, whether initially present or introduced by oxygen plasma treatment. The plasma treatment induces a uniform dispersion of Pt nanoparticles at the CNT surface. The absence of additional features in the C 1s core level spectrum indicates that no mixed PtC phase is formed. The formation of COPt bonds at the cluster-CNT interface is suggested to reduce the electronic interaction between Pt nanoparticles and the CNT surface.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000258830900025 Publication Date 2008-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 62 Open Access
Notes Pai Approved (up) Most recent IF: 1.815; 2008 IF: 2.169
Call Number UA @ lucian @ c:irua:76489 Serial 2652
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Author Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Ghijsen, J.; Ewels, C.P.
Title Study of the interaction between copper and carbon nanotubes Type A1 Journal article
Year 2012 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 535 Issue Pages 80-83
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Copper deposited by thermal evaporation onto pristine and oxygen plasma treated carbon nanotubes (CNTs) diffuse over the CNT surface, coalescing and forming crystalline islands. The nucleation sites of the islands are preferentially defects, and more homogeneous island dispersion was observed at the CNT oxygen functionalized surface. The presence of weakly bound oxygen atoms at the CNT surface induces the formation of CuO bonds at the Cu/CNT interface, as described through density functional calculations. Exposure to air allows further oxidation to facetted crystalline Cu2O. Oxygen plasma pre-treatment represents a promising route for homogenous disperse Cu2O nanoparticle decoration of CNTs.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000303437900015 Publication Date 2012-03-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 27 Open Access
Notes Approved (up) Most recent IF: 1.815; 2012 IF: 2.145
Call Number UA @ lucian @ c:irua:97704 Serial 3336
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Author Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Tagmatarchis, N.; Guttmann, P.
Title NEXAFS spectromicroscopy of suspended carbon nanohorns Type A1 Journal article
Year 2013 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 587 Issue Pages 85-87
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We demonstrate that near-edge X-ray-absorption fine-structure spectroscopy combined with full-field transmission X-ray microscopy can be used to study the electronic structure of suspended carbon nanohorns. Based on reports of electronic structure calculations additional spectral features observed in the π region of the NEXAFS spectrum recorded on the carbon nanohorns were associated to the presence of the pentagonal rings and the folding of the graphene sheet.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000326104500016 Publication Date 2013-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 4 Open Access
Notes Fp7; Countatoms; Approved (up) Most recent IF: 1.815; 2013 IF: 1.991
Call Number UA @ lucian @ c:irua:111592 Serial 2339
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Author Adjizian, J.J.; De Marco, P.; Suarez-Martinez, I.; El Mel, A.A.; Snyders, R.; Gengler, R.Y.N.; Rudolf, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Ewels, C.P.;
Title Platinum and palladium on carbon nanotubes : experimental and theoretical studies Type A1 Journal article
Year 2013 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 571 Issue Pages 44-48
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Pristine and oxygen plasma functionalised carbon nanotubes (CNTs) were studied after the evaporation of Pt and Pd atoms. High resolution transmission electron microscopy shows the formation of metal nanoparticles at the CNT surface. Oxygen functional groups grafted by the plasma functionalization act as nucleation sites for metal nanoparticles. Analysis of the C1s core level spectra reveals that there is no covalent bonding between the Pt or Pd atoms and the CNT surface. Unlike other transition metals such as titanium and copper, neither Pd nor Pt show strong oxygen interaction or surface oxygen scavenging behaviour.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000319109900007 Publication Date 2013-04-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 23 Open Access
Notes Countatoms; Cost Approved (up) Most recent IF: 1.815; 2013 IF: 1.991
Call Number UA @ lucian @ c:irua:108706 Serial 2650
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Author Ke, X.; Bals, S.; Cott, D.; Hantschel, T.; Bender, H.; Van Tendeloo, G.
Title Three-dimensional analysis of carbon nanotube networks in interconnects by electron tomography without missing wedge artifacts Type A1 Journal article
Year 2010 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume 16 Issue 2 Pages 210-217
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The three-dimensional (3D) distribution of carbon nanotubes (CNTs) grown inside semiconductor contact holes is studied by electron tomography. The use of a specialized tomography holder results in an angular tilt range of ±90°, which means that the so-called missing wedge is absent. The transmission electron microscopy (TEM) sample for this purpose consists of a micropillar that is prepared by a dedicated procedure using the focused ion beam (FIB) but keeping the CNTs intact. The 3D results are combined with energy dispersive X-ray spectroscopy (EDS) to study the relation between the CNTs and the catalyst particles used during their growth. The reconstruction, based on the full range of tilt angles, is compared with a reconstruction where a missing wedge is present. This clearly illustates that the missing wedge will lead to an unreliable interpretation and will limit quantitative studies
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge, Mass. Editor
Language Wos 000276137200011 Publication Date 2010-02-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.891 Times cited 42 Open Access
Notes Esteem 026019; Fwo; Iap-Vi Approved (up) Most recent IF: 1.891; 2010 IF: 3.259
Call Number UA @ lucian @ c:irua:82279 Serial 3642
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Author Wang, C.; Ke, X.; Wang, J.; Liang, R.; Luo, Z.; Tian, Y.; Yi, D.; Zhang, Q.; Wang, J.; Han, X.-F.; Van Tendeloo, G.; Chen, L.-Q.; Nan, C.-W.; Ramesh, R.; Zhang, J.
Title Ferroelastic switching in a layered-perovskite thin film Type A1 Journal article
Year 2016 Publication Nature communications Abbreviated Journal Nat Commun
Volume 7 Issue 7 Pages 10636
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A controllable ferroelastic switching in ferroelectric/multiferroic oxides is highly desirable due to the non-volatile strain and possible coupling between lattice and other order parameter in heterostructures. However, a substrate clamping usually inhibits their elastic deformation in thin films without micro/nano-patterned structure so that the integration of the non-volatile strain with thin film devices is challenging. Here, we report that reversible in-plane elastic switching with a non-volatile strain of approximately 0.4% can be achieved in layered-perovskite Bi2WO6 thin films, where the ferroelectric polarization rotates by 90 degrees within four in-plane preferred orientations. Phase-field simulation indicates that the energy barrier of ferroelastic switching in orthorhombic Bi2WO6 film is ten times lower than the one in PbTiO3 films, revealing the origin of the switching with negligible substrate constraint. The reversible control of the in-plane strain in this layered-perovskite thin film demonstrates a new pathway to integrate mechanical deformation with nanoscale electronic and/or magnetoelectronic applications.
Address Department of Physics, Beijing Normal University, 100875 Beijing, China
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000371020600002 Publication Date 2016-02-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 40 Open Access
Notes The work in Beijing Normal University is supported by the NSFC under contract numbers 51322207, 51332001 and 11274045. J.Z. also acknowledges the support from National Basic Research Program of China, under contract No. 2014CB920902. G.V.T. acknowledges the funding from the European Research Council under the Seventh Framework Program (FP7), ERC Advanced Grant No. 246791-COUNTATOMS. X.K. acknowledges the funding from NSFC (Grant No.11404016) and Beijing University of Technology (2015-RD-QB-19). J.W. acknowledges the funding from NSFC (Grant number 51472140). L.-Q.C. acknowledges the supporting by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award FG02-07ER46417. R.L. acknowledges Tsinghua National Laboratory for Information Science and Technology (TNList) Cross-discipline Foundation. Z.L. acknowledges the support from the NSFC (No.11374010 and No.11434009). Q.Z. and X.-F.H. acknowledge the funding support from NSFC (Grant No. 11434014). R.R. acknowledges support from the National Science Foundation (Nanosystems Engineering Research Center for Translational Applications of Nanoscale Multiferroic Systems) under grant number EEC-1160504. Approved (up) Most recent IF: 12.124
Call Number c:irua:130978 Serial 4007
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Author Li, J.; Pereira, P.J.; Yuan, J.; Lv, Y.-Y.; Jiang, M.-P.; Lu, D.; Lin, Z.-Q.; Liu, Y.-J.; Wang, J.-F.; Li, L.; Ke, X.; Van Tendeloo, G.; Li, M.-Y.; Feng, H.-L.; Hatano, T.; Wang, H.-B.; Wu, P.-H.; Yamaura, K.; Takayama-Muromachi, E.; Vanacken, J.; Chibotaru, L.F.; Moshchalkov, V.V.
Title Nematic superconducting state in iron pnictide superconductors Type A1 Journal article
Year 2017 Publication Nature communications Abbreviated Journal Nat Commun
Volume 8 Issue 1 Pages 1880
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nematic order often breaks the tetragonal symmetry of iron-based superconductors. It arises from regular structural transition or electronic instability in the normal phase. Here, we report the observation of a nematic superconducting state, by measuring the angular dependence of the in-plane and out-of-plane magnetoresistivity of Ba 0.5 K 0.5 Fe 2 As 2 single crystals. We find large twofold oscillations in the vicinity of the superconducting transition, when the direction of applied magnetic field is rotated within the basal plane. To avoid the influences from sample geometry or current flow direction, the sample was designed as Corbino-shape for in-plane and mesa-shape for out-of-plane measurements. Theoretical analysis shows that the nematic superconductivity arises from the weak mixture of the quasi-degenerate s-wave and d-wave components of the superconducting condensate, most probably induced by a weak anisotropy of stresses inherent to single crystals.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000416933400002 Publication Date 2017-11-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 8 Open Access OpenAccess
Notes The authors J.L., P.J.P., and J.Y. contributed equally to this work. J.L. and J.Y. designed the experiments. J.L., H.-L.F., K.Y., and E.T.-M. grew the single crystals. J.L., J.Y., Y.-Y.L., M.-P.J., D.L., M.-Y.L., T.H., H.-B.W., P.-H.W., K.Y., E.T.-M., J.V., and V.V.M. fabricated the devices and measured transport properties. J.L., Y.-Y.L., Z.-Q.L., Y.-J.L., J.-F.W., and L.L. studied on the pulsed high field measurements. X.K. and G.V.T. measured the low temperature TEM. All authors discussed the data. J.L., P.J.P., and L.F.C. proposed the model and simulated the results. J.L., P.J.P., K.Y., E.T.-M., and L.F.C. analyzed the data and prepared the manuscript. Approved (up) Most recent IF: 12.124
Call Number EMAT @ emat @c:irua:147348 Serial 4772
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Author Zhang, J.; Ke, X.; Gou, G.; Seidel, J.; Xiang, B.; Yu, P.; Liang, W.I.; Minor, A.M.; Chu, Y.h.; Van Tendeloo, G.; Ren, X.; Ramesh, R.;
Title A nanoscale shape memory oxide Type A1 Journal article
Year 2013 Publication Nature communications Abbreviated Journal Nat Commun
Volume 4 Issue Pages 2768-8
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Stimulus-responsive shape-memory materials have attracted tremendous research interests recently, with much effort focused on improving their mechanical actuation. Driven by the needs of nanoelectromechanical devices, materials with large mechanical strain, particularly at nanoscale level, are therefore desired. Here we report on the discovery of a large shape-memory effect in bismuth ferrite at the nanoscale. A maximum strain of up to ~14% and a large volumetric work density of ~600±90 J cm−3 can be achieved in association with a martensitic-like phase transformation. With a single step, control of the phase transformation by thermal activation or electric field has been reversibly achieved without the assistance of external recovery stress. Although aspects such as hysteresis, microcracking and so on have to be taken into consideration for real devices, the large shape-memory effect in this oxide surpasses most alloys and, therefore, demonstrates itself as an extraordinary material for potential use in state-of-art nanosystems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000328023900006 Publication Date 2013-11-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 67 Open Access
Notes Countatoms Approved (up) Most recent IF: 12.124; 2013 IF: 10.742
Call Number UA @ lucian @ c:irua:111431 Serial 2271
Permanent link to this record
 
 
Author Wang, J.T.W.; Cabana, L.; Bourgognon, M.; Kafa, H.; Protti, A.; Venner, K.; Shah, A.M.; Sosabowski, J.K.; Mather, S.J.; Roig, A.; Ke, X.; Van Tendeloo, G.; de Rosales, R.T.M.; Tobias, G.; Al-Jamal, K.T.
Title Magnetically decorated multiwalled carbon nanotubes as dual MRI and SPECT contrast agents Type A1 Journal article
Year 2014 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 24 Issue 13 Pages 1880-1894
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Carbon nanotubes (CNTs) are one of the most promising nanomaterials to be used in biomedicine for drug/gene delivery as well as biomedical imaging. This study develops radio-labeled, iron oxide-decorated multiwalled CNTs (MWNTs) as dual magnetic resonance (MR) and single photon emission computed tomography (SPECT) contrast agents. Hybrids containing different amounts of iron oxide are synthesized by in situ generation. Physicochemical characterisations reveal the presence of superparamagnetic iron oxide nanoparticles (SPION) granted the magnetic properties of the hybrids. Further comprehensive examinations including high resolution transmission electron microscopy (HRTEM), fast Fourier transform simulations, X-ray diffraction, and X-ray photoelectron spectroscopy assure the conformation of prepared SPION as γ-Fe2O3. High r2 relaxivities are obtained in both phantom and in vivo MRI compared to the clinically approved SPION Endorem. The hybrids are successfully radio labeled with technetium-99m through a functionalized bisphosphonate and enable SPECT/CT imaging and γ-scintigraphy to quantitatively analyze the biodistribution in mice. No abnormality is found by histological examination and the presence of SPION and MWNT are identified by Perls stain and Neutral Red stain, respectively. TEM images of liver and spleen tissues show the co-localization of SPION and MWNTs within the same intracellular vesicles, indicating the in vivo stability of the hybrids after intravenous injection. The results demonstrate the capability of the present SPIONMWNT hybrids as dual MRI and SPECT contrast agents for in vivo use.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000333674100007 Publication Date 2013-11-19
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 50 Open Access
Notes Countatoms; Fp7; Esteem2; esteem2_ta Approved (up) Most recent IF: 12.124; 2014 IF: 11.805
Call Number UA @ lucian @ c:irua:111589 Serial 1891
Permanent link to this record
 
 
Author Spyrou, K.; Potsi, G.; Diamanti, E.K.; Ke, X.; Serestatidou, E.; Verginadis, I.I.; Velalopoulou, A.P.; Evangelou, A.M.; Deligiannakis, Y.; Van Tendeloo, G.; Gournis, D.; Rudolf, P.;
Title Towards Novel Multifunctional Pillared Nanostructures: Effective Intercalation of Adamantylamine in Graphene Oxide and Smectite Clays Type A1 Journal article
Year 2014 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 24 Issue 37 Pages 5841-5850
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Multifunctional pillared materials are synthesized by the intercalation of cage-shaped adamantylamine (ADMA) molecules into the interlayer space of graphite oxide (GO) and aluminosilicate clays. The physicochemical and structural properties of these hybrids, determined by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Raman and X-ray photoemission (XPS) spectroscopies and transmission electron microscopy (TEM) show that they can serve as tunable hydrophobic/hydrophilic and stereospecific nanotemplates. Thus, in ADMA-pillared clay hybrids, the phyllomorphous clay provides a hydrophilic nanoenvironment where the local hydrophobicity is modulated by the presence of ADMA moieties. On the other hand, in the ADMA-GO hybrid, both the aromatic rings of GO sheets and the ADMA molecules define a hydrophobic nanoenvironment where sp(3)-oxo moieties (epoxy, hydroxyl and carboxyl groups), present on GO, modulate hydrophilicity. As test applications, these pillared nanostructures are capable of selective/stereospecific trapping of small chlorophenols or can act as cytotoxic agents.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000342794500008 Publication Date 2014-07-19
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 19 Open Access
Notes Approved (up) Most recent IF: 12.124; 2014 IF: 11.805
Call Number UA @ lucian @ c:irua:121085 Serial 3686
Permanent link to this record
 
 
Author Li, J.; Ji, M.; Schwarz, T.; Ke, X.; Van Tendeloo, G.; Yuan, J.; Pereira, P.J.; Huang, Y.; Zhang, G.; Feng, H.L.; Yuan, Y.H.; Hatano, T.; Kleiner, R.; Koelle, D.; Chibotaru, L.F.; Yamaura, K.; Wang, H.B.; Wu, P.H.; Takayama-Muromachi, E.; Vanacken, J.; Moshchalkov, V.V.;
Title Local destruction of superconductivity by non-magnetic impurities in mesoscopic iron-based superconductors Type A1 Journal article
Year 2015 Publication Nature communications Abbreviated Journal Nat Commun
Volume 6 Issue 6 Pages 7614
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The determination of the pairing symmetry is one of the most crucial issues for the iron-based superconductors, for which various scenarios are discussed controversially. Non-magnetic impurity substitution is one of the most promising approaches to address the issue, because the pair-breaking mechanism from the non-magnetic impurities should be different for various models. Previous substitution experiments demonstrated that the non-magnetic zinc can suppress the superconductivity of various iron-based superconductors. Here we demonstrate the local destruction of superconductivity by non-magnetic zinc impurities in Ba0.5K0.5Fe2As2 by exploring phase-slip phenomena in a mesoscopic structure with 119 × 102 nm2 cross-section. The impurities suppress superconductivity in a three-dimensional Swiss cheese-like pattern with in-plane and out-of-plane characteristic lengths slightly below ~1.34 nm. This causes the superconducting order parameter to vary along abundant narrow channels with effective cross-section of a few square nanometres. The local destruction of superconductivity can be related to Cooper pair breaking by non-magnetic impurities.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000358857000007 Publication Date 2015-07-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 12 Open Access
Notes 246791 Countatoms Approved (up) Most recent IF: 12.124; 2015 IF: 11.470
Call Number c:irua:126677 Serial 1827
Permanent link to this record
 
 
Author Li, Y.J.; Wang, J.J.; Ye, J.C.; Ke, X.X.; Gou, G.Y.; Wei, Y.; Xue, F.; Wang, J.; Wang, C.S.; Peng, R.C.; Deng, X.L.; Yang, Y.; Ren, X.B.; Chen, L.Q.; Nan, C.W.; Zhang, J.X.;
Title Mechanical switching of nanoscale multiferroic phase boundaries Type A1 Journal article
Year 2015 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 25 Issue 25 Pages 3405-3413
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Tuning the lattice degree of freedom in nanoscale functional crystals is critical to exploit the emerging functionalities such as piezoelectricity, shape-memory effect, or piezomagnetism, which are attributed to the intrinsic lattice-polar or lattice-spin coupling. Here it is reported that a mechanical probe can be a dynamic tool to switch the ferroic orders at the nanoscale multiferroic phase boundaries in BiFeO3 with a phase mixture, where the material can be reversibly transformed between the soft tetragonal-like and the hard rhombohedral-like structures. The microscopic origin of the nonvolatile mechanical switching of the multiferroic phase boundaries, coupled with a reversible 180 degrees rotation of the in-plane ferroelectric polarization, is the nanoscale pressure-induced elastic deformation and reconstruction of the spontaneous strain gradient across the multiferroic phase boundaries. The reversible control of the room-temperature multiple ferroic orders using a pure mechanical stimulus may bring us a new pathway to achieve the potential energy conversion and sensing applications.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000355992600017 Publication Date 2015-04-20
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 23 Open Access
Notes Approved (up) Most recent IF: 12.124; 2015 IF: 11.805
Call Number c:irua:126430 Serial 1976
Permanent link to this record
 
 
Author Ying, J.; Yang, X.-Y.; Hu, Z.-Y.; Mu, S.-C.; Janiak, C.; Geng, W.; Pan, M.; Ke, X.; Van Tendeloo, G.; Su, B.-L.
Title One particle@one cell : highly monodispersed PtPd bimetallic nanoparticles for enhanced oxygen reduction reaction Type A1 Journal article
Year 2014 Publication Nano energy Abbreviated Journal Nano Energy
Volume 8 Issue Pages 214-222
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Highly monodispersed platinum-based nanoalloys are the best-known catalysts for the oxygen reduction reaction. Although certainly promising, the durability and stability are among the main requirements for commercializing fuel cell electrocatalysts in practical applications. Herein, we synthesize highly stable, durable and catalytic active monodispersed PtPd nano-particles encapsulated in a unique one particle@one cell structure by adjusting the viscosity of solvents using mesocellular foam. PtPd nanoparticles in mesocellular carbon foam exhibit an excellent electrocatalytic activity (over 4 times mass and specific activities than the commercial Pt/C catalyst). Most importantly, this nanocatalyst shows no obvious change of structure and only a 29.5% loss in electrochemically active surface area after 5000 potential sweeps between 0.6 and 1.1 V versus reversible hydrogen electrode cycles. (C) 2014 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000340981700026 Publication Date 2014-06-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2211-2855; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.343 Times cited 40 Open Access
Notes Approved (up) Most recent IF: 12.343; 2014 IF: 10.325
Call Number UA @ lucian @ c:irua:119255 Serial 2465
Permanent link to this record
 
 
Author Song, H.-D.; Wu, Y.-F.; Yang, X.; Ren, Z.; Ke, X.; Kurttepeli, M.; Tendeloo, G.V.; Liu, D.; Wu, H.-C.; Yan, B.; Wu, X.; Duan, C.-G.; Han, G.; Liao, Z.-M.; Yu, D.
Title Asymmetric Modulation on Exchange Field in a Graphene/BiFeO3Heterostructure by External Magnetic Field Type A1 Journal article
Year 2018 Publication Nano letters Abbreviated Journal Nano Lett
Volume 18 Issue 4 Pages 2435-2441
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Graphene, having all atoms on its surface, is favorable to extend the functions by introducing the spin–orbit coupling and magnetism through proximity effect. Here, we report the tunable interfacial exchange field produced by proximity coupling in graphene/BiFeO3 heterostructures. The exchange field has a notable dependence with external magnetic field, and it is much larger under negative magnetic field than that under positive magnetic field. For negative external magnetic field, interfacial exchange coupling gives rise to evident spin splitting for N ≠ 0 Landau levels and a quantum Hall metal state for N = 0 Landau level. Our findings suggest graphene/BiFeO3 heterostructures are promising for spintronics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430155900034 Publication Date 2018-04-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 9 Open Access Not_Open_Access
Notes This work was supported by National Key Research and Development Program of China (No. 2016YFA0300802) and NSFC (Nos. 11774004 and 11604004). Ministry of Science and Technology of the People's Republic of China, 2016YFA0300802 ; National Natural Science Foundation of China, 11604004 11774004 ; Approved (up) Most recent IF: 12.712
Call Number EMAT @ lucian @c:irua:150794 Serial 4923
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Author Yan, Y.; Liao, Z.M.; Ke, X.; Van Tendeloo, G.; Wang, Q.; Sun, D.; Yao, W.; Zhou, S.; Zhang, L.; Wu, H.C.; Yu, D.P.;
Title Topological surface state enhanced photothermoelectric effect in Bi2Se3 nanoribbons Type A1 Journal article
Year 2014 Publication Nano letters Abbreviated Journal Nano Lett
Volume 14 Issue 8 Pages 4389-4394
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The photothermoelectric effect in topological insulator Bi2Se3 nanoribbons is studied. The topological surface states are excited to be spin-polarized by circularly polarized light. Because the direction of the electron spin is locked to its momentum for the spin-helical surface states, the photothermoelectric effect is significantly enhanced as the oriented motions of the polarized spins are accelerated by the temperature gradient. The results are explained based on the microscopic mechanisms of a photon induced spin transition from the surface Dirac cone to the bulk conduction band. The as-reported enhanced photothermoelectric effect is expected to have potential applications in a spin-polarized power source.
Address
Corporate Author Thesis
Publisher Place of Publication Washington Editor
Language Wos 000340446200028 Publication Date 2014-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 51 Open Access
Notes European Research Council under the Seventh Framework Program (FP7); ERC Advanced Grant No. 246791-COUNTATOMS. Approved (up) Most recent IF: 12.712; 2014 IF: 13.592
Call Number UA @ lucian @ c:irua:118128 Serial 3678
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Author Zhang, L.; Lin, B.-C.; Wu, Y.-F.; Wu, H.; Huang, T.-W.; Chang, C.-R.; Ke, X.; Kurttepeli, M.; Tendeloo, G.V.; Xu, J.; Yu, D.; Liao, Z.-M.
Title Electronic Coupling between Graphene and Topological Insulator Induced Anomalous Magnetotransport Properties Type A1 Journal article
Year 2017 Publication ACS nano Abbreviated Journal Acs Nano
Volume 11 Issue 11 Pages 6277-6285
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It has been theoretically proposed that the spin textures of surface states in a topological insulator can be directly transferred to graphene by means of the proximity effect, which is very important for realizing the two-dimensional topological insulator based on graphene. Here we report the anomalous magnetotransport properties of graphene-topological insulator Bi2Se3 heterojunctions, which are sensitive to the electronic coupling between graphene and the topological surface state. The coupling between the p_z orbitals of graphene and the p orbitals of the surface states on the Bi2Se3 bottom surface can be enhanced by applying a perpendicular negative magnetic field, resulting in a giant negative magnetoresistance at the Dirac point up to about -91%. Obvious resistances dip in the transfer curve at the Dirac point is also observed in the hybrid devices, which is consistent with theoretical predictions of the distorted Dirac bands with nontrivial spin textures inherited from the Bi2Se3 surface states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000404808000110 Publication Date 2017-05-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 12 Open Access OpenAccess
Notes ; This work was supported by National Key Research and Development Program of China (Nos. 2016YFA0300802, 2013CB934600) and NSFC (No. 11234001). ; Approved (up) Most recent IF: 13.942
Call Number EMAT @ emat @ c:irua:143192 Serial 4569
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Author Quintana, M.; Ke, X.; Van Tendeloo, G.; Meneghetti, M.; Bittencourt, C.; Prato, M.
Title Light-induced selective deposition of Au nanoparticles on single-wall carbon nanotubes Type A1 Journal article
Year 2010 Publication ACS nano Abbreviated Journal Acs Nano
Volume 4 Issue 10 Pages 6105-6113
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Novel applications of single-walled carbon nanotubes (SWNT) rely on the development of new strategies to make them easier to handle without affecting their structural properties. In this work, we have selectively deposited Au nanoparticles (Au NP) on SWNT assisted by UV light irradiation. XPS analysis and UV-vis spectroscopy indicate that the deposition occurs at the defects generated after oxidation of the SWNT. By addition of n-dodecylthiol, the separation of oxidized tubes with Au NP (Au-ox-SWNT) from tubes devoid of Au NP (bare tubes, b-SWNT) was achieved. Raman and UV-vis-NIR spectra indicate that UV irradiation induces a faster nucleation of Au NP on metallic SWNT. This new technique can be useful for the preparation of nanohybrid composites with enhanced properties, as increased thermal stability, and to obtain purified SWNT.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000283453700081 Publication Date 2010-09-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 26 Open Access
Notes Approved (up) Most recent IF: 13.942; 2010 IF: 9.865
Call Number UA @ lucian @ c:irua:99202 Serial 1819
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Author Felten, A.; Gillon, X.; Gulas, M.; Pireaux, J.-J.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Najafi, E.; Hitchcock, A.P.
Title Measuring point defect density in individual carbon nanotubes using polarization-dependent X-ray microscopy Type A1 Journal article
Year 2010 Publication ACS nano Abbreviated Journal Acs Nano
Volume 4 Issue 8 Pages 4431-4436
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The presence of defects in carbon nanotubes strongly modifies their electrical, mechanical, and chemical properties. It was long thought undesirable, but recent experiments have shown that introduction of structural defects using ion or electron irradiation can lead to novel nanodevices. We demonstrate a method for detecting and quantifying point defect density in individual carbon nanotubes (CNTs) based on measuring the polarization dependence (linear dichroism) of the C 1s → π* transition at specific locations along individual CNTs with a scanning transmission X-ray microscope (STXM). We show that STXM can be used to probe defect density in individual CNTs with high spatial resolution. The quantitative relationship between ion dose, nanotube diameter, and defect density was explored by purposely irradiating selected sections of nanotubes with kiloelectronvolt (keV) Ga+ ions. Our results establish polarization-dependent X-ray microscopy as a new and very powerful characterization technique for carbon nanotubes and other anisotropic nanostructures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281052700014 Publication Date 2010-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 26 Open Access
Notes Approved (up) Most recent IF: 13.942; 2010 IF: 9.865
Call Number UA @ lucian @ c:irua:84734 Serial 1966
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Author Suarez-Martinez, I.; Ewels, C.P.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Felten, A.; Pireaux, J.-J.; Ghijsen, J.; Bittencourt, C.
Title Study of the interface between rhodium and carbon nanotubes Type A1 Journal article
Year 2010 Publication ACS nano Abbreviated Journal Acs Nano
Volume 4 Issue 3 Pages 1680-1686
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract X-ray photoelectron spectroscopy at 3.5 keV photon energy, in combination with high-resolution transmission electron microscopy, is used to follow the formation of the interface between rhodium and carbon nanotubes. Rh nucleates at defect sites, whether initially present or induced by oxygen-plasma treatment. More uniform Rh cluster dispersion is observed on plasma-treated CNTs. Experimental results are compared to DFT calculations of small Rh clusters on pristine and defective graphene. While Rh interacts as strongly with the carbon as Ti, it is less sensitive to the presence of oxygen, suggesting it as a good candidate for nanotube contacts.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000275858200053 Publication Date 2010-02-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 26 Open Access
Notes Approved (up) Most recent IF: 13.942; 2010 IF: 9.865
Call Number UA @ lucian @ c:irua:82440 Serial 3337
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Author Bertoni, G.; Grillo, V.; Brescia, R.; Ke, X.; Bals, S.; Catellani, A.; Li, H.; Manna, L.
Title Direct determination of polarity, faceting, and core location in colloidal core/shell wurtzite semiconductor nanocrystals Type A1 Journal article
Year 2012 Publication ACS nano Abbreviated Journal Acs Nano
Volume 6 Issue 7 Pages 6453-6461
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The ability to determine the atomic arrangement and termination of various facets of surfactant-coated nanocrystals is of great importance for understanding their growth mechanism and their surface properties and represents a critical piece of information that can be coupled to other experimental techniques and to calculations. This is especially appealing in the study of nanocrystals that can be grown in strongly anisotropic shapes, for which the relative growth rates of various facets can be influenced under varying reaction conditions. Here we show that in two representative cases of rod-shaped nanocrystals in the wurtzite phase (CdSe(core)/CdS(shell) and ZnSe(core)/ZnS(shell) nanorods) the terminations of the polar facets can be resolved unambiguously by combining advanced electron microscopy techniques, such as aberration-corrected HRTEM with exit wave reconstruction or aberration-corrected HAADF-STEM. The [0001] and [000-1] polar directions of these rods, which grow preferentially along their c-axis, are revealed clearly, with one side consisting of the Cd (or Zn)-terminated (0001) facet and the other side with a pronounced faceting due to Cd (or Zn)-terminated {10-1-1} facets. The lateral faceting of the rods is instead dominated by three nonpolar {10-10} facets. The core buried in the nanostructure can be localized in both the exit wave phase and HAADF-STEM images.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000306673800079 Publication Date 2012-06-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 63 Open Access
Notes The authors gratefully acknowledge funding from the European Research Council under grant number 240111 (NANO-ARCH) and the financial support from the Flemish Hercules 3 Programme for large infrastructures. G.B. and V.G. thank E. Rotunno for his help with STEM_CELL and IWFR. Approved (up) Most recent IF: 13.942; 2012 IF: 12.062
Call Number UA @ lucian @ c:irua:101138 Serial 710
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Author Quintana, M.; López, A.M.; Rapino, S.; Toma, F.M.; Iurlo, M.; Carraro, M.; Sartorel, A.; Maccato, C.; Ke, X.; Bittencourt, C.; Da Ros, T.; Van Tendeloo, G.; Marcaccio, M.; Paolucci, F.; Prato, M.; Bonchio, M.;
Title Knitting the catalytic pattern of artificial photosynthesis to a hybrid graphene nanotexture Type A1 Journal article
Year 2013 Publication ACS nano Abbreviated Journal Acs Nano
Volume 7 Issue 1 Pages 811-817
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The artificial leaf project calls for new materials enabling multielectron catalysis with minimal overpotential, high turnover frequency, and long-term stability. Is graphene a better material than carbon nanotubes to enhance water oxidation catalysis for energy applications? Here we show that functionalized graphene with a tailored distribution of polycationic, quaternized, ammonium pendants provides an sp(2) carbon nanoplatform to anchor a totally inorganic tetraruthenate catalyst, mimicking the oxygen evolving center of natural PSII. The resulting hybrid material displays oxygen evolution at overpotential as low as 300 mV at neutral pH with negligible loss of performance after 4 h testing. This multilayer electroactive asset enhances the turnover frequency by 1 order of magnitude with respect to the isolated catalyst, and provides a definite up-grade of the carbon nanotube material, with a similar surface functionalization. Our innovation is based on a noninvasive, synthetic protocol for graphene functionalization that goes beyond the ill-defined oxidation-reduction methods, allowing a definite control of the surface properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000314082800088 Publication Date 2012-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 69 Open Access
Notes 246791 COUNTATOMS; 262348 ESMI; ESF Cost Action NanoTP MP0901 Approved (up) Most recent IF: 13.942; 2013 IF: 12.033
Call Number UA @ lucian @ c:irua:107707 Serial 1766
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Author Groeneveld, E.; Witteman, L.; Lefferts, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; de Mello Donega, C.
Title Tailoring ZnSe-CdSe colloidal quantum dots via cation exchange : from core/shell to alloy nanocrystals Type A1 Journal article
Year 2013 Publication ACS nano Abbreviated Journal Acs Nano
Volume 7 Issue 9 Pages 7913-7930
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We report a study of Zn2+ by Cd2+ cation exchange (CE) in colloidal ZnSe nanocrystals (NCs). Our results reveal that CE in ZnSe NCs is a thermally activated isotropic process. The CE efficiency (i.e., fraction of Cd2+ ions originally in solution, Cdsol, that is incorporated in the ZnSe NC) increases with temperature and depends also on the Cdsol/ZnSe ratio. Interestingly, the reaction temperature can be used as a sensitive parameter to tailor both the composition and the elemental distribution profile of the product (Zn,Cd)Se NCs. At 150 °C ZnSe/CdSe core/shell hetero-NCs (HNCs) are obtained, while higher temperatures (200 and 220 °C) produce (Zn1xCdx)Se gradient alloy NCs, with increasingly smoother gradients as the temperature increases, until homogeneous alloy NCs are obtained at T ≥ 240 °C. Remarkably, sequential heating (150 °C followed by 220 °C) leads to ZnSe/CdSe core/shell HNCs with thicker shells, rather than (Zn1xCdx)Se gradient alloy NCs. Thermal treatment at 250 °C converts the ZnSe/CdSe core/shell HNCs into (Zn1xCdx)Se homogeneous alloy NCs, while preserving the NC shape. A mechanism for the cation exchange in ZnSe NCs is proposed, in which fast CE takes place at the NC surface, and is followed by relatively slower thermally activated solid-state cation diffusion, which is mediated by Frenkel defects. The findings presented here demonstrate that cation exchange in colloidal ZnSe NCs provides a very sensitive tool to tailor the nature and localization regime of the electron and hole wave functions and the optoelectronic properties of colloidal ZnSeCdSe NCs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000330016900051 Publication Date 2013-08-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 153 Open Access
Notes 262348 Esmi; 246791 Countatoms Approved (up) Most recent IF: 13.942; 2013 IF: 12.033
Call Number UA @ lucian @ c:irua:110038 Serial 3469
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Author Yan, Y.; Zhou, X.; Jin, H.; Li, C.-Z.; Ke, X.; Van Tendeloo, G.; Liu, K.; Yu, D.; Dressel, M.; Liao, Z.-M.
Title Surface-Facet-Dependent Phonon Deformation Potential in Individual Strained Topological Insulator Bi2Se3 Nanoribbons Type A1 Journal article
Year 2015 Publication ACS nano Abbreviated Journal Acs Nano
Volume 9 Issue 9 Pages 10244-10251
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Strain is an important method to tune the properties of topological insulators. For example, compressive strain can induce superconductivity in Bi2Se3 bulk material. Topological insulator nanostructures are the superior candidates to utilize the unique surface states due to the large surface to volume ratio. Therefore, it is highly desirable to monitor the local strain effects in individual topological insulator nanostructures. Here, we report the systematical micro-Raman spectra of single strained Bi2Se3 nanoribbons with different thicknesses and different surface facets, where four optical modes are resolved in both Stokes and anti-Stokes Raman spectral lines. A striking anisotropy of the strain dependence is observed in the phonon frequency of strained Bi2Se3 nanoribbons grown along the ⟨112̅0⟩ direction. The frequencies of the in-plane Eg2 and out-of-plane A1g1 modes exhibit a nearly linear blue-shift against bending strain when the nanoribbon is bent along the ⟨112̅0⟩ direction with the curved {0001} surface. In this case, the phonon deformation potential of the Eg2 phonon for 100 nm-thick Bi2Se3 nanoribbon is up to 0.94 cm–1/%, which is twice of that in Bi2Se3 bulk material (0.52 cm–1/%). Our results may be valuable for the strain modulation of individual topological insulator nanostructures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000363915300079 Publication Date 2015-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 14 Open Access
Notes Y.Y. would like to thank Xuewen Fu for helpful discussions. This work was supported by MOST (Nos. 2013CB934600, 2013CB932602) and NSFC (Nos. 11274014, 11234001). Approved (up) Most recent IF: 13.942; 2015 IF: 12.881
Call Number c:irua:129216 Serial 3963
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Author Chen, J.J.; Wang, Q.; Meng, J.; Ke, X.; Van Tendeloo, G.; Bie, Y.Q.; Liu, J.; Liu, K.; Liao, Z.M.; Sun, D.; Yu, D.;
Title Photovoltaic effect and evidence of carrier multiplication in graphene vertical homojunctions with asymmetrical metal contacts Type A1 Journal article
Year 2015 Publication ACS nano Abbreviated Journal Acs Nano
Volume 9 Issue 9 Pages 8851-8858
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Graphene exhibits exciting potentials for high-speed wideband photodetection and high quantum efficiency solar energy harvest because of its broad spectral absorption, fast photoelectric response, and potential carrier multiplication. Although photocurrent can be generated near a metalgraphene interface in lateral devices, the photoactive area is usually limited to a tiny one-dimensional line-like interface region. Here, we report photoelectric devices based on vertical graphene two-dimensional homojunction, which is fabricated via vertically stacking four graphene monolayers with asymmetric metal contacts. The devices show excellent photovoltaic output with excitation wavelength ranging from visible light to mid-infrared. The wavelength dependence of the internal quantum efficiency gives direct evidence of the carrier multiplication effect in graphene. The simple fabrication process, easy scale-up, large photoresponsive active area, and broadband response of the vertical graphene device are very promising for practical applications in optoelectronics and photovoltaics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000361935800023 Publication Date 2015-08-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 11 Open Access
Notes 246791 Countatoms Approved (up) Most recent IF: 13.942; 2015 IF: 12.881
Call Number c:irua:127689 Serial 2615
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Author Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.;
Title Gold clusters on WO3 nanoneedles grown via AACVD : XPS and TEM studies Type A1 Journal article
Year 2012 Publication Materials chemistry and physics Abbreviated Journal Mater Chem Phys
Volume 134 Issue 2/3 Pages 809-813
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000305918200038 Publication Date 2012-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0254-0584; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.084 Times cited 52 Open Access
Notes Iap Approved (up) Most recent IF: 2.084; 2012 IF: 2.072
Call Number UA @ lucian @ c:irua:97705 Serial 1356
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Author Corthals, S.; van Noyen, J.; Liang, D.; Ke, X.; Van Tendeloo, G.; Jacobs, P.; Sels, B.
Title A cyclic catalyst pretreatment in CO2 for high yield production of Carbon nanofibers with narrow diameter distribution Type A1 Journal article
Year 2011 Publication Catalysis letters Abbreviated Journal Catal Lett
Volume 141 Issue 11 Pages 1621-1624
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract This paper presents a cyclic catalyst pretreatment process to improve the CNF yield with narrow size distribution by sequentially feeding the CVD reactor with CH4/CO2 mixtures (carbon deposition) and CO2 (carbon removal) prior to the actual growth process. A mechanism based on a break-up of large Ni particles tentatively explains the beneficial effect of the cyclic carbon deposition/removal CVD procedure.
Address
Corporate Author Thesis
Publisher Place of Publication Basel Editor
Language Wos 000296471400006 Publication Date 2011-09-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1011-372X;1572-879X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.799 Times cited 1 Open Access
Notes Iwt; Iap Approved (up) Most recent IF: 2.799; 2011 IF: 2.242
Call Number UA @ lucian @ c:irua:91888 Serial 598
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Author Ke, X.; Bals, S.; Romo Negreira, A.; Hantschel, T.; Bender, H.; Van Tendeloo, G.
Title TEM sample preparation by FIB for carbon nanotube interconnects Type A1 Journal article
Year 2009 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 109 Issue 11 Pages 1353-1359
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000270765800006 Publication Date 2009-07-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 21 Open Access
Notes Esteem 026019; Iap Approved (up) Most recent IF: 2.843; 2009 IF: 2.067
Call Number UA @ lucian @ c:irua:79074 Serial 3485
Permanent link to this record
 
 
Author Felten, A.; Suarez-Martinez, I.; Ke, X.; Van Tendeloo, G.; Ghijsen, J.; Pireaux, J.-J.; Drube, W.; Bittencourt, C.; Ewels, C.P.
Title The role of oxygen at the interface between titanium and carbon nanotubes Type A1 Journal article
Year 2009 Publication ChemPhysChem : a European journal of chemical physics and physical chemistry Abbreviated Journal Chemphyschem
Volume 10 Issue 11 Pages 1799-1804
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We study the interface between carbon nanotubes (CNTs) and surface-deposited titanium using electron microscopy and photoemission spectroscopy, supported by density functional calculations. Charge transfer from the Ti atoms to the nanotube and carbide formation is observed at the interface which indicates strong interaction. Nevertheless, the presence of oxygen between the Ti and the CNTs significantly weakens the Ti-CNT interaction. Ti atoms at the surface will preferentially bond to oxygenated sites. Potential sources of oxygen impurities are examined, namely oxygen from any residual atmosphere and pre-existing oxygen impurities on the nanotube surface, which we enhance through oxygen plasma surface pre-treatment. Variation in literature data concerning Ohmic contacts between Ti and carbon nanotubes is explained via sample pre-treatment and differing vacuum levels, and we suggest improved treatment routes for reliable Schottky barrier-free Ti-nanotube contact formation.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000268817800015 Publication Date 2009-05-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1439-4235;1439-7641; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.075 Times cited 38 Open Access
Notes Pai Approved (up) Most recent IF: 3.075; 2009 IF: 3.453
Call Number UA @ lucian @ c:irua:77939 Serial 2918
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Author Bittencourt, C.; van Lier, G.; Ke, X.; Suarez-Martinez, I.; Felten, A.; Ghijsen, J.; Van Tendeloo, G.; Ewels, C.O.
Title Spectroscopy and defect identification for fluorinated carbon nanotubes Type A1 Journal article
Year 2009 Publication ChemPhysChem : a European journal of chemical physics and physical chemistry Abbreviated Journal Chemphyschem
Volume 10 Issue 6 Pages 920-925
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Multi-wall carbon nanotubes (MWCNTs) were exposed to a CF4 radio-frequency (rf) plasma. High-resolution photoelectron spectroscopy shows that the treatment effectively grafts fluorine atoms onto the MWCNTs, altering the valence electronic states. Fluorine surface concentration can be tuned by varying the exposure time. Evaporation of gold onto MWCNTs is used to mark active site formation. High-resolution transmission electron microscopy coupled with density functional theory (DFT) modelling is used to characterise the surface defects formed, indicating that the plasma treatment does not etch the tube surface. We suggest that this combination of theory and microscopy of thermally evaporated gold atoms onto the CNT surface may be a powerful approach to characterise both surface defect density as well as defect type.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000265469200011 Publication Date 2009-03-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1439-4235;1439-7641; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.075 Times cited 14 Open Access
Notes Iuap; Fwo Approved (up) Most recent IF: 3.075; 2009 IF: 3.453
Call Number UA @ lucian @ c:irua:77315 Serial 3073
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