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Author (down) Zhou, X.-G.; Yang, C.-Q.; Sang, X.; Li, W.; Wang, L.; Yin, Z.-W.; Han, J.-R.; Li, Y.; Ke, X.; Hu, Z.-Y.; Cheng, Y.-B.; Van Tendeloo, G. pdf  doi
openurl 
  Title Probing the electron beam-induced structural evolution of halide perovskite thin films by scanning transmission electron microscopy Type A1 Journal article
  Year 2021 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C  
  Volume 125 Issue 19 Pages 10786-10794  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract A deep understanding of the fine structure at the atomic scale of halide perovskite materials has been limited by their sensitivity to the electron beam that is widely used for structural characterization. The sensitivity of a gamma-CsPbIBr2 perovskite thin film under electron beam irradiation is revealed by scanning transmission electron microscopy (STEM) through a universal large-range electron dose measurement, which is based on discrete single-electron events in the STEM mode. Our research indicates that the gamma-CsPbIBr2 thin film undergoes structural changes with increasing electron overall dose (e(-).A(-2)) rather than dose rate (e(-).A(-2).s(-1)), which suggests that overall dose is the key operative parameter. The electron beam-induced structural evolution of gamma-CsPbIBr2 is monitored by fine control of the electron beam dose, together with the analysis of high-resolution (S)TEM, diffraction, and energy-dispersive X-ray spectroscopy. Our results show that the gamma-CsPbIBr2 phase first forms an intermediate phase [e.g., CsPb(1-x)(IBr)((3-y))] with a superstructure of ordered vacancies in the pristine unit cell, while a fraction of Pb2+ is reduced to Pb-0. As the electron dose increases, Pb nanoparticles precipitate, while the remaining framework forms the Cs2IBr phase, accompanied by some amorphization. This work provides guidelines to minimize electron beam irradiation artifacts for atomic-resolution imaging on CsPbIBr2 thin films.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000655640900061 Publication Date 2021-05-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.536  
  Call Number UA @ admin @ c:irua:179187 Serial 6880  
Permanent link to this record
 

 
Author (down) Zhong, R.; Peng, L.; de Clippel, F.; Gommes, C.; Goderis, B.; Ke, X.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. pdf  doi
openurl 
  Title An eco-friendly soft template synthesis of mesostructured silica-carbon nanocomposites for acid catalysis Type A1 Journal article
  Year 2015 Publication ChemCatChem Abbreviated Journal Chemcatchem  
  Volume 7 Issue 7 Pages 3047-3058  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The synthesis of ordered mesoporous silica-carbon composites was explored by employing TEOS and sucrose as the silica and carbon precursor respectively, and the triblock copolymer F127 as a structure-directing agent via an evaporation-induced self-assembly (EISA) process. It is demonstrated that the synthesis procedures allow for control of the textural properties and final composition of these silica-carbon nanocomposites via adjustment of the effective SiO2/C weight ratio. Characterization by SAXS, N-2 physisorption, HRTEM, TGA, and C-13 and Si-29 solid-state MAS NMR show a 2D hexagonal mesostructure with uniform large pore size ranging from 5.2 to 7.6nm, comprising of separate carbon phases in a continuous silica phase. Ordered mesoporous silica and non-ordered porous carbon can be obtained by combustion of the pyrolyzed nanocomposites in air or etching with HF solution, respectively. Sulfonic acid groups can be readily introduced to such kind of silica-carbon nanocomposites by a standard sulfonation procedure with concentrated sulfuric acid. Excellent acid-catalytic activities and selectivities for the dimerization of styrene to produce 1,3-diphenyl-1-butene and dimerization of -methylstyrene to unsaturated dimers were demonstrated with the sulfonated materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000361189400037 Publication Date 2015-09-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1867-3880; 1867-3899 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.803 Times cited 13 Open Access  
  Notes Approved Most recent IF: 4.803; 2015 IF: 4.556  
  Call Number UA @ lucian @ c:irua:127836 Serial 4138  
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Author (down) 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. url  doi
openurl 
  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 Most recent IF: 13.942  
  Call Number EMAT @ emat @ c:irua:143192 Serial 4569  
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Author (down) 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. pdf  doi
openurl 
  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 Most recent IF: 12.343; 2014 IF: 10.325  
  Call Number UA @ lucian @ c:irua:119255 Serial 2465  
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Author (down) Yan, Y.; Zhou, X.; Jin, H.; Li, C.-Z.; Ke, X.; Van Tendeloo, G.; Liu, K.; Yu, D.; Dressel, M.; Liao, Z.-M. url  doi
openurl 
  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 Most recent IF: 13.942; 2015 IF: 12.881  
  Call Number c:irua:129216 Serial 3963  
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Author (down) Yan, Y.; Wang, L.-X.; Ke, X.; Van Tendeloo, G.; Wu, X.-S.; Yu, D.-P.; Liao, Z.-M. pdf  url
doi  openurl
  Title High-mobility Bi2Se3 nanoplates manifesting quantum oscillations of surface states in the sidewalls Type A1 Journal article
  Year 2014 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 4 Issue Pages 3817-7  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Magnetotransport measurements of topological insulators are very important to reveal the exotic topological surface states for spintronic applications. However, the novel properties related to the surface Dirac fermions are usually accompanied by a large linear magnetoresistance under perpendicular magnetic field, which makes the identification of the surface states obscure. Here, we report prominent Shubnikov-de Haas (SdH) oscillations under an in-plane magnetic field, which are identified to originate from the surface states in the sidewalls of topological insulator Bi2Se3 nanoplates. Importantly, the SdH oscillations appear with a dramatically weakened magnetoresistance background, offering an easy path to probe the surface states directly when the coexistence of surface states and bulk conduction is inevitable. Moreover, under a perpendicular magnetic field, the oscillations in Hall conductivity have peak-to-valley amplitudes of 2 e(2)/h, giving confidence to achieve a quantum Hall effect in this system. A cross-section view of the nanoplate shows that the sidewall is (015) facet dominant and therefore forms a 586 angle with regard to the top/ bottom surface instead of being perpendicular; this gives credit to the surface states' behavior as two-dimensional transport.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos 000330044700008 Publication Date 2014-01-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited 31 Open Access  
  Notes ERC grant Nu246791 – COUNTATOMS Approved Most recent IF: 4.259; 2014 IF: 5.578  
  Call Number UA @ lucian @ c:irua:114815 Serial 1436  
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Author (down) 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. pdf  doi
openurl 
  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 Most recent IF: 12.124; 2014 IF: 11.805  
  Call Number UA @ lucian @ c:irua:111589 Serial 1891  
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Author (down) 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. url  doi
openurl 
  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 Most recent IF: 12.124  
  Call Number c:irua:130978 Serial 4007  
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Author (down) Vidick, D.; Ke, X.; Devillers, M.; Poleunis, C.; Delcorte, A.; Moggi, P.; Van Tendeloo, G.; Hermans, S. pdf  url
doi  openurl
  Title Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers Type A1 Journal article
  Year 2015 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech  
  Volume 6 Issue 6 Pages 1287-1297  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Heterometal clusters containing Ru and Au, Co and/or Pt are anchored onto carbon nanotubes and nanofibers functionalized with chelating phosphine groups. The cluster anchoring yield is related to the amount of phosphine groups available on the nanocarbon surface. The ligands of the anchored molecular species are then removed by gentle thermal treatment in order to form nanoparticles. In the case of Au-containing clusters, removal of gold atoms from the clusters and agglomeration leads to a bimodal distribution of nanoparticles at the nanocarbon surface. In the case of Ru-Pt species, anchoring occurs without reorganization through a ligand exchange mechanism. After thermal treatment, ultrasmall (1-3 nm) bimetal Ru-Pt nanoparticles are formed on the surface of the nanocarbons. Characterization by high resolution transmission electron microscopy (HRTEM) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) confirms their bimetal nature on the nanoscale. The obtained bimetal nanoparticles supported on nanocarbon were tested as catalysts in ammonia synthesis and are shown to be active at low temperature and atmospheric pressure with very low Ru loading.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000355908400001 Publication Date 2015-06-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.127 Times cited 7 Open Access  
  Notes 246791 Countatoms; 262348 Esmi Approved Most recent IF: 3.127; 2015 IF: 2.670  
  Call Number c:irua:126431 Serial 1420  
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Author (down) Vereecke, B.; van der Veen, M.H.; Sugiura, M.; Kashiwagi, Y.; Ke, X.; Cott, D.J.; Hantschel, T.; Huyghebaert, C.; Tökei, Z. pdf  doi
openurl 
  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 Most recent IF: 1.384; 2013 IF: 1.057  
  Call Number UA @ lucian @ c:irua:108713 Serial 3902  
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Author (down) van der Stam, W.; Gradmann, S.; Altantzis, T.; Ke, X.; Baldus, M.; Bals, S.; de Mello Donega, C. pdf  url
doi  openurl
  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  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000384399000037 Publication Date 2016-09-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 27 Open Access OpenAccess  
  Notes 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 (down) van der Stam, W.; Berends, A.C.; Rabouw, F.T.; Willhammar, T.; Ke, X.; Meeldijk, J.D.; Bals, S.; de Donega, C.M. pdf  url
doi  openurl
  Title Luminescent CuInS2 quantum dots by partial cation exchange in Cu2-xS nanocrystals Type A1 Journal article
  Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 27 Issue 27 Pages 621-628  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Here, we show successful partial cation exchange reactions in Cu2-xS nanocrystals (NCs) yielding luminescent CuInS2 (CIS) NCs. Our approach of mild reaction conditions ensures slow Cu extraction rates, which results in a balance with the slow In incorporation rate. With this method, we obtain CIS NCs with photoluminescence (PL) far in the near-infrared (NIR), which cannot be directly synthesized by currently available synthesis protocols. We discuss the factors that favor partial, self-limited cation exchange from Cu2-xS to CIS NCs, rather than complete cation exchange to In2S3. The product CIS NCs have the wurtzite crystal structure, which is understood in terms of conservation of the hexagonal close packing of the anionic sublattice of the parent NCs into the product NCs. These results are an important step toward the design of CIS NCs with sizes and shapes that are not attainable by direct synthesis protocols and may thus impact a number of potential applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000348618400028 Publication Date 2014-12-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 119 Open Access OpenAccess  
  Notes 335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 9.466; 2015 IF: 8.354  
  Call Number c:irua:125291 Serial 1858  
Permanent link to this record
 

 
Author (down) van der Stam, W.; Akkerman, Q.A.; Ke, X.; van Huis, M.A.; Bals, S.; de Donega, C.M. pdf  url
doi  openurl
  Title Solution-processable ultrathin size- and shape-controlled colloidal Cu2-xS nanosheets Type A1 Journal article
  Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 27 Issue 27 Pages 283-291  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Ultrathin two-dimensional (2D) nanosheets (NSs) possess extraordinary properties that are attractive for both fundamental studies and technological devices. Solution-based bottom-up methods are emerging as promising routes to produce free-standing NSs, but the synthesis of colloidal NSs with well-defined size and shape has remained a major challenge. In this work, we report a novel method that yields 2 nm thick colloidal Cu2-xS NSs with well-defined shape (triangular or hexagonal) and size (100 nm to 3 mu m). The key feature of our approach is the use of a synergistic interaction between halides (Br or Cl) and copper-thiolate metal-organic frameworks to create a template that imposes 2D constraints on the Cu-catalyzed C-S thermolysis, resulting in nucleation and growth of colloidal 2D Cu2-xS NSs. Moreover, the NS composition can be postsynthetically tailored by exploiting topotactic cation exchange reactions. This is illustrated by converting the Cu2-xS NSs into ZnS and CdS NSs while preserving their size and shape. The method presented here thus holds great promise as a route to solution-processable compositionally diverse ultrathin colloidal NSs with well-defined shape and size.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000348085300036 Publication Date 2014-12-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 68 Open Access OpenAccess  
  Notes 335078 Colouratom; 246791 Countatoms; 312483 Esteem2; esteem2ta; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 9.466; 2015 IF: 8.354  
  Call Number c:irua:123865 c:irua:123865 Serial 3052  
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Author (down) Ustarroz, J.; Ke, X.; Hubin, A.; Bals, S.; Terryn, H. pdf  doi
openurl 
  Title New insights into the early stages of nanoparticle electrodeposition Type A1 Journal article
  Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 116 Issue 3 Pages 2322-2329  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Electrodeposition is an increasingly important method to synthesize supported nanoparticles, yet the early stages of electrochemical nanoparticle formation are not perfectly understood. In this paper, the early stages of silver nanoparticle electrodeposition on carbon substrates have been studied by aberration-corrected TEM, using carbon-coated TEM grids as electrochemical electrodes. In this manner we have access to as-deposited nanoparticle size distribution and structural characterization at the atomic scale combined with electrochemical measurements, which represents a breakthrough in a full understanding of the nanoparticle electrodeposition mechanisms. Whereas classical models, based upon characterization at the nanoscale, assume that electrochemical growth is only driven by direct attachment, the results reported hereafter indicate that early nanoparticle growth is mostly driven by nanocluster surface movement and aggregation. Hence, we conclude that electrochemical nulceation and growth models should be revised and that an electrochemical aggregative growth mechanism should be considered in the early stages of nanoparticle electrodeposition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000299584400037 Publication Date 2011-12-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 104 Open Access  
  Notes Fwo Approved Most recent IF: 4.536; 2012 IF: 4.814  
  Call Number UA @ lucian @ c:irua:96225 Serial 2316  
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Author (down) Tsoufis, T.; Georgakilas, V.; Ke, X.; Van Tendeloo, G.; Rudolf, P.; Gournis, D. pdf  doi
openurl 
  Title Incorporation of pure fullerene into organoclays : towards C60-pillared clay structures Type A1 Journal article
  Year 2013 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J  
  Volume 19 Issue 24 Pages 7937-7943  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract In this work, we demonstrate the successful incorporation of pure fullerene from solution into two-dimensional layered aluminosilicate minerals. Pure fullerenes are insoluble in water and neutral in terms of charge, hence they cannot be introduced into the clay galleries by ion exchange or intercalation from water solution. To overcome this bottleneck, we organically modified the clay with quaternary amines by using well-established reactions in clay science in order to expand the interlayer space and render the galleries organophilic. During the reaction with the fullerene solution, the organic solvent could enter into the clay galleries, thus transferring along the fullerene molecules. Furthermore, we demonstrate that the surfactant molecules, can be selectively removed by either simple ion-exchange reaction (e.g., interaction with Al(NO3)3 solution to replace the surfactant molecules with Al3+ ions) or thermal treatment (heating at 350 °C) to obtain novel fullerene-pillared clay structures exhibiting enhanced surface area. The synthesized hybrid materials were characterized in detail by a combination of experimental techniques including powder X-ray diffraction, transmission electron microscopy, X-ray photoemission, and UV/Vis spectroscopy as well as thermal analysis and nitrogen adsorptiondesorption measurements. The reported fullerene-pillared clay structures constitute a new hybrid system with very promising potential for the use in areas such as gas storage and/or gas separation due to their high surface area.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000319825500035 Publication Date 2013-04-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0947-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.317 Times cited 3 Open Access  
  Notes 262348 Esmi; 246791 Countatoms Approved Most recent IF: 5.317; 2013 IF: 5.696  
  Call Number UA @ lucian @ c:irua:107347 Serial 1599  
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Author (down) Suarez-Martinez, I.; Ewels, C.P.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Felten, A.; Pireaux, J.-J.; Ghijsen, J.; Bittencourt, C. pdf  doi
openurl 
  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 Most recent IF: 13.942; 2010 IF: 9.865  
  Call Number UA @ lucian @ c:irua:82440 Serial 3337  
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Author (down) Suarez-Martinez, I.; Bittencourt, C.; Ke, X.; Felten, A.; Pireaux, J.J.; Ghijsen, J.; Drube, W.; Van Tendeloo, G.; Ewels, C.P. pdf  doi
openurl 
  Title Probing the interaction between gold nanoparticles and oxygen functionalized carbon nanotubes Type A1 Journal article
  Year 2009 Publication Carbon Abbreviated Journal Carbon  
  Volume 47 Issue 6 Pages 1549-1554  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The interaction between evaporated gold and pristine or oxygen plasma treated multi-walled carbon nanotubes (MWCNTs) is investigated. Experimental and theoretical results indicate that gold nucleation occurs at defect sites, whether initially present or introduced by oxygen plasma treatment. Uniform gold cluster dispersion is observed on plasma treated carbon nanotubes (CNTs) and associated with the presence of uniformly dispersed oxidized vacancy centres on the CNT surface.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000265518700018 Publication Date 2009-02-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.337 Times cited 38 Open Access  
  Notes Pai Approved Most recent IF: 6.337; 2009 IF: 4.504  
  Call Number UA @ lucian @ c:irua:77267 Serial 2717  
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Author (down) 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. pdf  doi
openurl 
  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 Most recent IF: 12.712  
  Call Number EMAT @ lucian @c:irua:150794 Serial 4923  
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Author (down) Skaltsas, T.; Ke, X.; Bittencourt, C.; Tagmatarchis, N. doi  openurl
  Title Ultrasonication induces oxygenated species and defects onto exfoliated graphene Type A1 Journal article
  Year 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 117 Issue 44 Pages 23272-23278  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The effect of ultrasonication parameters, such as time and power applied, to exfoliate graphite in o-dichlorobenzene (o-DCB) and N-methyl-1,2-pyrrolidone (NMP) was examined. It was found that the concentration of graphene was higher in o-DCB, while its dispersibility was increased when sonication was applied for a longer period and/or at higher power. However, spectroscopic examination by X-ray photoelectron spectroscopy (XPS) revealed that ultrasonication causes defects and induces oxygen functional groups in the form of carboxylic acids and ethers/epoxides onto the graphene lattice. Additional proof for the latter arose from Raman, IR, and thermogravimetry studies. The carboxylic acids and ethers/epoxides onto exfoliated graphene were derived from air during ultrasonication and found independent of the solvent used for the exfoliation and the power and/or time ultrasonication applied. Quantitative evaluation of the amount of oxygenated species present on exfoliated graphene as performed by high-resolution XPS revealed that the relative oxygen percentage was higher when exfoliation was performed in NMP. Finally, the sonication time and/or power affected the oxygen content on exfoliated graphene, since extended ultrasonication resulted in a decrease in the oxygen content on exfoliated graphene, with a simultaneous increase of defected sp(3) carbon atoms.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000326845400090 Publication Date 2013-10-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 65 Open Access  
  Notes Approved Most recent IF: 4.536; 2013 IF: 4.835  
  Call Number UA @ lucian @ c:irua:112710 Serial 3797  
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Author (down) Schulze, A.; Hantschel, T.; Dathe, A.; Eyben, P.; Ke, X.; Vandervorst, W. pdf  doi
openurl 
  Title Electrical tomography using atomic force microscopy and its application towards carbon nanotube-based interconnects Type A1 Journal article
  Year 2012 Publication Nanotechnology Abbreviated Journal Nanotechnology  
  Volume 23 Issue 30 Pages 305707  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The fabrication and integration of low-resistance carbon nanotubes (CNTs) for interconnects in future integrated circuits requires characterization techniques providing structural and electrical information at the nanometer scale. In this paper we present a slice-and-view approach based on electrical atomic force microscopy. Material removal achieved by successive scanning using doped ultra-sharp full-diamond probes, manufactured in-house, enables us to acquire two-dimensional (2D) resistance maps originating from different depths (equivalently different CNT lengths) on CNT-based interconnects. Stacking and interpolating these 2D resistance maps results in a three-dimensional (3D) representation (tomogram). This allows insight from a structural (e.g. size, density, distribution, straightness) and electrical point of view simultaneously. By extracting the resistance evolution over the length of an individual CNT we derive quantitative information about the resistivity and the contact resistance between the CNT and bottom electrode.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000306333500029 Publication Date 2012-07-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0957-4484;1361-6528; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.44 Times cited 29 Open Access  
  Notes Approved Most recent IF: 3.44; 2012 IF: 3.842  
  Call Number UA @ lucian @ c:irua:100750 Serial 895  
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Author (down) Ribbens, S.; Meynen, V.; Van Tendeloo, G.; Ke, X.; Mertens, M.; Maes, B.U.W.; Cool, P.; Vansant, E.F. pdf  doi
openurl 
  Title Development of photocatalytic efficient Ti-based nanotubes and nanoribbons by conventional and microwave assisted synthesis strategies Type A1 Journal article
  Year 2008 Publication Microporous and mesoporous materials: zeolites, clays, carbons and related materials Abbreviated Journal Micropor Mesopor Mat  
  Volume 114 Issue 1/3 Pages 401-409  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY)  
  Abstract Titanate nanotubes were prepared via a hydrothermal treatment of TiO2 powders (Riedel De Haen) in a basic solution. Morphology and structure of the prepared samples were characterized by high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), XRD, FT-Raman spectroscopy, nitrogen sorption and DSC. The photocatalytic activity was evaluated by photocatalytic oxidation of rhodamine 6G. Trititanate nanotubes (TTNT) with inner pore diameters between 4 and 4.2 nm and surface areas up till 360 m(2)/g could be synthesized. The synthesis route was modified by introduction of a calcination step, by applying a lower hydrothermal temperature and microwave irradiation in order to increase the photocatalytic activity of the porous photoactive nanotubular materials. Calcination and a softer hydrothermal treatment led to the formation of anatase without affecting the surface area and nanotubular shape of the samples. In this way, the photocatalytic activity of the original trititanate nanotubes could be significantly increased. By making use of microwave assisted synthesis, the photocatalytic activity call also be increased due to the presence of anatase. However, by applying microwave synthesis, a different structure was obtained, nanoribbons (NR) instead of nanotubcs, resulting in a decrease in surface area and porosity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000258432100040 Publication Date 2008-02-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1387-1811; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.615 Times cited 47 Open Access  
  Notes Fwo; Crp (Ua) Approved Most recent IF: 3.615; 2008 IF: 2.555  
  Call Number UA @ lucian @ c:irua:69696 Serial 683  
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Author (down) Ribbens, S.; Beyers, E.; Schellens, K.; Mertens, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; Meynen, V.; Cool, P. pdf  doi
openurl 
  Title Systematic evaluation of thermal and mechanical stability of different commercial and synthetic photocatalysts in relation to their photocatalytic activity Type A1 Journal article
  Year 2012 Publication Microporous and mesoporous materials: zeolites, clays, carbons and related materials Abbreviated Journal Micropor Mesopor Mat  
  Volume 156 Issue Pages 62-72  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)  
  Abstract The effect of thermal treatment and mechanical stress on the structural and photocatalytic properties of eight different (synthetic and commercial) photocatalysts has been thoroughly investigated. Different mesoporous Ti-based materials were prepared via surfactant based synthesis routes (e.g. Pluronic 123, CTMABr = Cetyltrimethylammonium bromide) or via template-free synthesis routes (e.g. trititanate nanotubes). Also, the stabilizing effect of the NaOH/NH4OH post-treatment on the templated mesoporous materials and their photocatalytic activity was investigated. Furthermore, the thermal and mechanical properties of commercially available titanium dioxides such as P25 Evonik® and Millenium PC500® were studied. The various photocatalysts were analyzed with N2-sorption, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) to obtain information concerning the specific surface area, pore volume, crystal structure, morphology, phase transitions, etc. In general, results show that the NaOH post-treatment leads to an increased control of the crystallization process during calcination resulting in a higher thermal stability, but at the same time diminishes the photocatalytic activity. Mesoporous materials in which pre-synthesized nanoparticles are used as titania source have the best mechanical stability whereas the mechanical stability of the nanotubes is the most limited. At increased temperatures and pressures, the tested commercial titanium dioxides lose their superior photocatalytic activity caused by a decreased accessibility of the active sites. The observed changes in adsorption capacities and photocatalytic activities cannot be assigned to one single phenomenon. In this respect, it shows the need to define a general/standard method to compare different photocatalysts. Furthermore, it is shown that the photocatalytic properties do not necessarily deteriorate under thermal stress, but can be improved due to crystallization, even though the initial material is (partially) destroyed. It is shown that the usefulness of a specific type of photocatalyst strongly depends on the application and the temperature/pressure to which it needs to resist.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000303625200010 Publication Date 2012-02-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1387-1811; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.615 Times cited 8 Open Access  
  Notes Fwo Approved Most recent IF: 3.615; 2012 IF: 3.365  
  Call Number UA @ lucian @ c:irua:96910 Serial 3466  
Permanent link to this record
 

 
Author (down) Quintana, M.; Ke, X.; Van Tendeloo, G.; Meneghetti, M.; Bittencourt, C.; Prato, M. pdf  doi
openurl 
  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 Most recent IF: 13.942; 2010 IF: 9.865  
  Call Number UA @ lucian @ c:irua:99202 Serial 1819  
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Author (down) Pietra, F.; van Dijk-Moes, R.J.A.; Ke, X.; Bals, S.; Van Tendeloo, G.; de Mello Donega, C.; Vanmaekelbergh, D. pdf  doi
openurl 
  Title Synthesis of highly luminescent silica-coated CdSe/CdS nanorods Type A1 Journal article
  Year 2013 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 25 Issue 17 Pages 3427-3434  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract CdSe(core)/CdS(shell) nanorods (NRs) have been extensively investigated for their unique optical properties, such as high photoluminescence (PL) quantum efficiency (QE) and polarized light emission. The incorporation of these NRs in silica (SiO2) is of high interest, since this renders them processable in polar solvents while increasing their photochemical stability, which would be beneficial for their application in LEDs and as biolabels. We report the synthesis of highly luminescent silica-coated CdSe/CdS NRs, by using the reverse micelle method. The mechanism for the encapsulation of the NRs in silica is unravelled and shown to be strongly influenced by the NR shape and its asymmetry. This is attributed to both the different morphology and the different crystallographic nature of the facets terminating the opposite tips of the NRs. These results lead to the formation of a novel class of NR architectures, whose symmetry can be controlled by tuning the degree of coverage of the silica shell. Interestingly, the encapsulation of the NRs in silica leads to a remarkable increase in their photostability, while preserving their optical properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000330097900004 Publication Date 2013-08-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 46 Open Access  
  Notes 262348 ESMI; 246791 COUNTATOMS; Hercules Approved Most recent IF: 9.466; 2013 IF: 8.535  
  Call Number UA @ lucian @ c:irua:110037 Serial 3456  
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Author (down) Peng, L.; Philippaerts, A.; Ke, X.; van Noyen, J.; de Cleppel, F.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. doi  openurl
  Title Preparation of sulfonated ordered mesoporous carbon and its use for the esterification of fatty acids Type A1 Journal article
  Year 2010 Publication Catalysis today Abbreviated Journal Catal Today  
  Volume 150 Issue 1/2 Pages 140-146  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Mesoporous carbon, which can be replicated from mesoporous silica and whose surface is hydrophobic, can be an ideal catalyst for the esterification of fatty acids. Here we report an easy and low cost way to prepare sulfonic acid group-functionalized mesoporous carbon. A sample of calcined mesoporous silica SBA-15 was added to an aqueous sucrose solution followed by drying and calcination at different temperatures. In contrast to existing procedures, the obtained hybrid Si/C material was then first sulfonated in H2SO4, before the final removal of the silica template in order to stabilize the porous structure towards the liquid phase sulfonation treatment. Thus the silicacarbon composites, instead of the mesoporous carbon, were successfully sulfonated to introduce SO3H groups, while keeping the ordered mesoporous structure intact. The influence of carbonization temperature was investigated, suggesting an optimum temperature of 873 K. The SO3H group-functionalized mesoporous carbon, denoted as CMK-3-873-SO3H, was characterized by means of XRD, N2 physisorption, SEM, FT-IR, elemental analysis and TEM. It followed that a uniform mesoporous carbon was obtained with an average pore size of 3.89 nm, a specific surface of 807 m2/g and a SO3H group loading of 0.39 meq/g of dry material. Compared with other solid acid catalysts, the resulting material shows enhanced activity in the acid-catalyzed esterification of oleic acid with methanol, and can be used repeatedly. The increased catalytic performance is attributed to the hydrophobic surface and larger pore size of the new catalyst. It can effectively accommodate long chain fatty acids and reject formed water, making the active sites easily accessible.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000275566700024 Publication Date 2009-09-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0920-5861; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.636 Times cited 132 Open Access  
  Notes Approved Most recent IF: 4.636; 2010 IF: 2.993  
  Call Number UA @ lucian @ c:irua:81739 Serial 2706  
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Author (down) Liu, J.; Hu, Z.-Y.; Peng, Y.; Huang, H.-W.; Li, Y.; Wu, M.; Ke, X.-X.; Van Tendeloo, G.; Su, B.-L. pdf  url
doi  openurl
  Title 2D ZnO mesoporous single-crystal nanosheets with exposed {0001} polar facets for the depollution of cationic dye molecules by highly selective adsorption and photocatalytic decomposition Type A1 Journal article
  Year 2016 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ  
  Volume 181 Issue 181 Pages 138-145  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Two dimensional (2D) ZnO nanosheets are ideal system for dimensionally confined transport phenomenon investigation owing to specific surface atomic configuration. Therefore, 2D ZnO porous nanosheets with single-crystal nature and {0001} polar facets, likely display some specific physicochemical properties. In this work, for the first time, 2D ZnO mesoporous single-crystal nanosheets (ZnO-MSN) with {0001} polar facets have been designed and prepared via an intriguing colloidal templating approach through controlling the infiltration speed for the suspension of EG-capped ZnO nanoparticles and polymer colloids. The EG-capped ZnO nanoparticles are very helpful for single-crystal nanosheet formation, while the polymer colloids play dual roles on the mesoporosity generation and {0001} polar facets formation within the mesopores. Such special 2D structure not only accelerates the hole-electron separation and the electron transportation owing to the single-crystal nature, but also enhances the selective adsorption of organic molecules owing to the porous structure and the exposed {0001} polar facets with more O-termination (000-1) surfaces: the 2D ZnO-MSN shows highly selective adsorption and significantly higher photodegradation for positively charged rhodamine B than those for negatively charged methyl orange and neutral phenol, comparing with ZnO nanoparticles (ZnO-NP) and ZnO commercial nanoparticles (ZnO-CNP) with high surface areas. This work may shed some light on better understanding the synthesis of 2D porous single-crystal nanosheet with exposed polar surfaces and photocatalytic mechanism of nanostructured semiconductors in a mixed organic molecules system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000364256000015 Publication Date 2015-08-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0926-3373; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.446 Times cited 60 Open Access  
  Notes 246791 Countatoms Approved Most recent IF: 9.446  
  Call Number c:irua:127638 c:irua:127638 c:irua:127638 Serial 10  
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Author (down) 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. url  doi
openurl 
  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 Most recent IF: 12.124  
  Call Number EMAT @ emat @c:irua:147348 Serial 4772  
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Author (down) Li, H.; Zhang, L.; Li, L.; Wu, C.; Huo, Y.; Chen, Y.; Liu, X.; Ke, X.; Luo, J.; Van Tendeloo, G. pdf  doi
openurl 
  Title Two-in-one solution using insect wings to produce graphene-graphite films for efficient electrocatalysis Type A1 Journal article
  Year 2019 Publication Nano Research Abbreviated Journal Nano Res  
  Volume 12 Issue 1 Pages 33-39  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Natural organisms contain rich elements and naturally optimized smart structures, both of which have inspired various innovative concepts and designs in human society. In particular, several natural organisms have been used as element sources to synthesize low-cost and environmentally friendly electrocatalysts for the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries, which are clean energy devices. However, to date, no naturally optimized smart structures have been employed in the synthesis of ORR catalysts, including graphene-based materials. Here, we demonstrate a novel strategy to synthesize graphene-graphite films (GGFs) by heating butterfly wings coated with FeCl3 in N-2, in which the full power of natural organisms is utilized. The wings work not only as an element source for GGF generation but also as a porous supporting structure for effective nitrogen doping, two-dimensional spreading, and double-face exposure of the GGFs. These GGFs exhibit a half-wave potential of 0.942 V and a H2O2 yield of < 0.07% for ORR electrocatalysis; these values are comparable to those for the best commercial Pt/C and all previously reported ORR catalysts in alkaline media. This two-in-one strategy is also successful with cicada and dragonfly wings, indicating that it is a universal, green, and cost-effective method for developing high-performance graphene-based materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000453629900004 Publication Date 2018-08-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1998-0124 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 7.354 Times cited 7 Open Access Not_Open_Access  
  Notes ; The authors would like to thank Drs Qiang Wang and Wenjuan Yuan for useful discussions. This work was financially supported by the National Key R&D Program of China (No. 2017YFA0700104), the National Natural Science Foundation of China (Nos. 21601136 and 11404016), the National Program for Thousand Young Talents of China, Tianjin Municipal Education Commission, Tianjin Municipal Science and Technology Commission (No. 15JCYBJC52600), and the Fundamental Research Fund of Tianjin University of Technology. This work also made use of the resources of the National Center for Electron Microscopy in Beijing. ; Approved Most recent IF: 7.354  
  Call Number UA @ admin @ c:irua:156210 Serial 5265  
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Author (down) Ke, X.; Bittencourt, C.; Van Tendeloo, G. pdf  url
doi  openurl
  Title Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials Type A1 Journal article
  Year 2015 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech  
  Volume 6 Issue 6 Pages 1541-1557  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract A major revolution for electron microscopy in the past decade is the introduction of aberration correction, which enables one to increase both the spatial resolution and the energy resolution to the optical limit. Aberration correction has contributed significantly to the imaging at low operating voltages. This is crucial for carbon-based nanomaterials which are sensitive to electron irradiation. The research of carbon nanomaterials and nanohybrids, in particular the fundamental understanding of defects and interfaces, can now be carried out in unprecedented detail by aberration-corrected transmission electron microscopy (AC-TEM). This review discusses new possibilities and limits of AC-TEM at low voltage, including the structural imaging at atomic resolution, in three dimensions and spectroscopic investigation of chemistry and bonding. In situ TEM of carbon-based nanomaterials is discussed and illustrated through recent reports with particular emphasis on the underlying physics of interactions between electrons and carbon atoms.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000357977300001 Publication Date 2015-07-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.127 Times cited 10 Open Access  
  Notes 246791 Countatoms Approved Most recent IF: 3.127; 2015 IF: 2.670  
  Call Number c:irua:126857 Serial 2682  
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Author (down) Ke, X.; Bittencourt, C.; Bals, S.; Van Tendeloo, G. pdf  url
doi  openurl
  Title Low-dose patterning of platinum nanoclusters on carbon nanotubes by focused-electron-beam-induced deposition as studied by TEM Type A1 Journal article
  Year 2013 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech  
  Volume 4 Issue Pages 77-86  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Focused-electron-beam-induced deposition (FEBID) is used as a direct-write approach to decorate ultrasmall Pt nanoclusters on carbon nanotubes at selected sites in a straightforward maskless manner. The as-deposited nanostructures are studied by transmission electron microscopy (TEM) in 2D and 3D, demonstrating that the Pt nanoclusters are well-dispersed, covering the selected areas of the CNT surface completely. The ability of FEBID to graft nanoclusters on multiple sides, through an electron-transparent target within one step, is unique as a physical deposition method. Using high-resolution TEM we have shown that the CNT structure can be well preserved thanks to the low dose used in FEBID. By tuning the electron-beam parameters, the density and distribution of the nanoclusters can be controlled. The purity of as-deposited nanoclusters can be improved by low-energy electron irradiation at room temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000314499700001 Publication Date 2013-02-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.127 Times cited 12 Open Access  
  Notes 262348 ESMI; 246791 COUNTATOMS; FWO G002410N; ESF Cost Action NanoTP MP0901 Approved Most recent IF: 3.127; 2013 IF: 2.332  
  Call Number UA @ lucian @ c:irua:106187 Serial 1848  
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