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Author Bretos, I.; Schneller, T.; Falter, M.; Baecker, M.; Hollmann, E.; Woerdenweber, R.; Molina-Luna, L.; Van Tendeloo, G.; Eibl, O.
Title Solution-derived YBa2Cu3O7-\delta (YBCO) superconducting films with BaZrO3 (BZO) nanodots based on reverse micelle stabilized nanoparticles Type A1 Journal article
Year 2015 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
Volume 3 Issue 3 Pages 3971-3979
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Superconducting YBa2Cu3O7-delta (YBCO) films with artificial BaZrO3 (BZO) nanodots were prepared using a chemical solution deposition method involving hybrid solutions composed of trifluoroacetate-based YBCO precursors and reverse micelle stabilized BZO nanoparticle dispersions. Microemulsion-mediated synthesis was used to obtain nano-sized (similar to 12 nm) and mono-dispersed BZO nanoparticles that preserve their features once introduced into the YBCO solution, as revealed by dynamic light scattering. Phase pure, epitaxial YBCO films with randomly oriented BZO nanodots distributed over their whole microstructure were grown from the hybrid solutions on (100) LaAlO3 substrates. The morphology of the YBCO-BZO nanocomposite films was strongly influenced by the amount of nanoparticles incorporated into the system, with contents ranging from 5 to 40 mol%. Scanning electron microscopy showed a high density of isolated second-phase defects consisting of BZO nanodots in the nanocomposite film with 10 mol% of BZO. Furthermore, a direct observation and quantitative analysis of lattice defects in the form of interfacial edge dislocations directly induced by the BZO nanodots was evidenced by transmission electron microscopy. The superconducting properties (77 K) of the YBCO films improved considerably by the presence of such nanodots, which seem to enhance the morphology of the sample and therefore the intergranular critical properties. The incorporation of preformed second-phase defects (here, BZO) during the growth of the superconducting phase is the main innovation of this novel approach for the all-solution based low-cost fabrication of long-length coated conductors.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000352870400018 Publication Date 2015-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526; 2050-7534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.256 Times cited 19 Open Access
Notes This work was supported by the German Federal Ministry of Economics and Technology (BMWi) contract no. 0327433A (project ELSA). L. Molina-Luna and G. Van Tendeloo acknowledge funding from the European Research Council (ERC grant no. 24691-COUNTATOMS). The authors gratefully acknowledge J. Dornseiffer for the support with preparation of the microemulsions for the BZO nanoparticles; G. Wasse for the SEM images; and T. Po¨ssinger for the preparation of the artwork. Eurotape Approved Most recent IF: 5.256; 2015 IF: 4.696
Call Number UA @ lucian @ c:irua:132575 Serial 4245
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Author Lu, Y.-G.; Turner, S.; Ekimov, E.A.; Verbeeck, J.; Van Tendeloo, G.
Title Boron-rich inclusions and boron distribution in HPHT polycrystalline superconducting diamond Type A1 Journal article
Year 2015 Publication Carbon Abbreviated Journal Carbon
Volume 86 Issue 86 Pages 156-162
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Polycrystalline boron-doped superconducting diamond, synthesized at high pressure and high temperature (HPHT) via a reaction of a single piece of crystalline boron with monolithic graphite, has been investigated by analytical transmission electron microscopy. The local boron distribution and boron environment have been studied by a combination of (scanning) transmission electron microscopy ((S)TEM) and spatially resolved electron energy-loss spectroscopy (EELS). High resolution TEM imaging and EELS elemental mapping have established, for the first time, the presence of largely crystalline diamond-diamond grain boundaries within the material and have evidenced the presence of substitutional boron dopants within individual diamond grains. Confirmation of the presence of substitutional B dopants has been obtained through comparison of acquired boron K-edge EELS fine structures with known references. This confirmation is important to understand the origin of superconductivity in polycrystalline B-doped diamond. In addition to the substitutional boron doping, boron-rich inclusions and triple-points, both amorphous and crystalline, with chemical compositions close to boron carbide B4C, are evidenced. (C) 2015 Elsevier Ltd. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos (up) 000352922700019 Publication Date 2015-01-22
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 20 Open Access
Notes FWO; 246791 COUNTATOMS; 278510 VORTEX; Hercules ECASJO_; Approved Most recent IF: 6.337; 2015 IF: 6.196
Call Number c:irua:125994UA @ admin @ c:irua:125994 Serial 250
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Author McCalla, E.; Sougrati, M.T.; Rousse, G.; Berg, E.J.; Abakumov, A.; Recham, N.; Ramesha, K.; Sathiya, M.; Dominko, R.; Van Tendeloo, G.; Novák, P.; Tarascon, J.M.;
Title Understanding the roles of anionic redox and oxygen release during electrochemical cycling of lithium-rich layered Li4FeSbO6 Type A1 Journal article
Year 2015 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 137 Issue 137 Pages 4804-4814
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Li-rich oxides continue to be of immense interest as potential next generation Li-ion battery positive electrodes, and yet the role of oxygen during cycling is still poorly understood. Here, the complex electrochemical behavior of Li4FeSbO6 materials is studied thoroughly with a variety of methods. Herein, we show that oxygen release occurs at a distinct voltage plateau from the peroxo/superoxo formation making this material ideal for revealing new aspects of oxygen redox processes in Li-rich oxides. Moreover, we directly demonstrate the limited reversibility of the oxygenated species (O-2(n-); n = 1, 2, 3) for the first time. We also find that during charge to 4.2 V iron is oxidized from +3 to an unusual +4 state with the concomitant formation of oxygenated species. Upon further charge to 5.0 V, an oxygen release process associated with the reduction of iron +4 to +3 is present, indicative of the reductive coupling mechanism between oxygen and metals previously reported. Thus, in full state of charge, lithium removal is fully compensated by oxygen only, as the iron and antimony are both very close to their pristine states. Besides, this charging step results in complex phase transformations that are ultimately destructive to the crystallinity of the material. Such findings again demonstrate the vital importance of fully understanding the behavior of oxygen in such systems. The consequences of these new aspects of the electrochemical behavior of lithium-rich oxides are discussed in detail.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000353177100036 Publication Date 2015-03-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863;1520-5126; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited 86 Open Access
Notes Approved Most recent IF: 13.858; 2015 IF: 12.113
Call Number c:irua:126019 Serial 3805
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Author Lieberman, C.M.; Filatov, A.S.; Wei, Z.; Rogachev, A.Y.; Abakumov, A.M.; Dikarev, E.V.
Title Mixed-valent, heteroleptic homometallic diketonates as templates for the design of volatile heterometallic precursors Type A1 Journal article
Year 2015 Publication Chemical science Abbreviated Journal Chem Sci
Volume 6 Issue 6 Pages 2835-2842
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A novel series of mixed-valent, heteroleptic transition metal diketonates that can be utilized as prospective single-source precursors for the low-temperature preparation of oxide materials are reported. The first mixed-valent iron beta-diketonates with different Fe-III/Fe-II ratios have been synthesized by applying the mixed-ligand approach. Based on nearly quantitative reaction yields and analysis of iron-oxygen bonds, these compounds were formulated as [Fe-III(acac)(3)][Fe-II(hfac)(2)] (1) and [Fe-II(hfac)(2)][Fe-III(acac)(3)][Fe-II(hfac)(2)] (2). In the above heteroleptic complexes, the Lewis acidic, coordinatively unsaturated Fe-II centers chelated by two hfac (hexafluoroacetylacetonate) ligands with electron-withdrawing substituents maintain bridging interactions with oxygen atoms of electron-donating acac (acetylacetonate) groups that chelate the neighboring Fe-III atoms. Switching the ligands on Fe-III and Fe-II atoms in starting reagents resulted in the instant ligand exchange between iron centers and in yet another polynuclear homometallic diketonate [Fe-II(hfac)(2)][Fe-III(acac)(2)(hfac)][Fe-II(hfac)(2)] (3) that adheres to the same bonding pattern as in complexes 1 and 2. The proposed synthetic methodology has been extended to design heterometallic diketonates with different M : M' ratios. Homometallic parent molecules have been used as templates to obtain heterometallic mixed-valent [Fe-III(acac)(3)][Mn-II(hfac)(2)] (4) and [Ni-II(hfac)(2)] – [Fe-III(acac)(3)][Ni-II(hfac)(2)] (5) complexes. The combination of two different diketonate ligands with electron-donating and electron-withdrawing substituents was found to be crucial for maintaining the above mixed-valent heterometallic assemblies. Theoretical investigation of two possible “isomers”, [Fe-III(acac)(3)][Mn-II(hfac)(2)] (4) and [Mn-III(acac)(3)][Fe-II(hfac)(2)] (40) provided an additional support for the metal site assignment giving a preference of 9.78 kcal mol(-1) for the molecule 4. Heterometallic complexes obtained in the course of this study have been found to act as effective single-source precursors for the synthesis of mixed-transition metal oxide materials MxM2-xO3 and MxMi-xO. The title highly volatile precursors can be used for the low-temperature preparation of both amorphous and crystalline heterometallic oxides in the form of thin films or nanosized particles that are known to operate as efficient catalysts in oxygen evolution reaction.
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Corporate Author Thesis
Publisher Royal Society of Chemistry Place of Publication Cambridge Editor
Language Wos (up) 000353223100021 Publication Date 2015-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-6520;2041-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.668 Times cited 13 Open Access
Notes Approved Most recent IF: 8.668; 2015 IF: 9.211
Call Number c:irua:126031 Serial 2092
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Author Gjorgievska, E.; Van Tendeloo, G.; Nicholson, J.W.; Coleman, N.J.; Slipper, I.J.; Booth, S.
Title The incorporation of nanoparticles into conventional glass-ionomer dental restorative cements Type A1 Journal article
Year 2015 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume 21 Issue 21 Pages 392-406
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Conventional glass-ionomer cements (GICs) are popular restorative materials, but their use is limited by their relatively low mechanical strength. This paper reports an attempt to improve these materials by incorporation of 10 wt% of three different types of nanoparticles, aluminum oxide, zirconium oxide, and titanium dioxide, into two commercial GICs (ChemFil((R)) Rock and EQUIA (TM) Fil). The results indicate that the nanoparticles readily dispersed into the cement matrix by hand mixing and reduced the porosity of set cements by filling the empty spaces between the glass particles. Both cements showed no significant difference in compressive strength with added alumina, and ChemFil((R)) Rock also showed no significant difference with zirconia. By contrast, ChemFil((R)) Rock showed significantly higher compressive strength with added titania, and EQUIA (TM) Fil showed significantly higher compressive strength with both zirconia and titania. Fewer air voids were observed in all nanoparticle-containing cements and this, in turn, reduced the development of cracks within the matrix of the cements. These changes in microstructure provide a likely reason for the observed increases in compressive strength, and overall the addition of nanoparticles appears to be a promising strategy for improving the physical properties of GICs.
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Corporate Author Thesis
Publisher Place of Publication Cambridge, Mass. Editor
Language Wos (up) 000353514700014 Publication Date 2015-02-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.891 Times cited 15 Open Access
Notes Approved Most recent IF: 1.891; 2015 IF: 1.877
Call Number UA @ lucian @ c:irua:132523 Serial 4194
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Author Filippousi, M.; Turner, S.; Katsikini, M.; Pinakidou, F.; Zamboulis, D.; Pavlidou, E.; Van Tendeloo, G.
Title Direct observation and structural characterization of natural and metal ion-exchanged HEU-type zeolites Type A1 Journal article
Year 2015 Publication Microporous and mesoporous materials: zeolites, clays, carbons and related materials Abbreviated Journal Micropor Mesopor Mat
Volume 210 Issue 210 Pages 185-193
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The atomic structure of natural HEU-type zeolite and two ion-exchanged variants of the zeolite, Ag+ (Ag-HEU) and Zn2+ (Zn-HEU) ion exchanged HEU-type zeolites, are investigated using advanced transmission electron microscopy techniques in combination with X-ray powder diffraction and X-ray absorption fine structure measurements. In both ion-exchanged materials, loading of the natural HEU zeolite is confirmed. Using low-voltage, aberration-corrected transmission electron microscopy at low-dose conditions, the local crystal structure of natural HEU-type zeolite is determined and the interaction of the ion-exchanged natural zeolites with the Ag+ and Zn2+ ions is studied. In the case of Ag-HEU, the presence of Ag+ ions and clusters at extra-framework sites as well as Ag nanoparticles has been confirmed. The Ag nanoparticles are preferentially positioned at the zeolite surface. For Zn-HEU, no large Zn(O) nanopartides are present, instead, the HEU channels are evidenced to be decorated by small Zn(O) clusters. (c) 2015 Elsevier Inc. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000353733300024 Publication Date 2015-02-13
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 5 Open Access
Notes 246791 Countatoms; Iap-Pai; Fwo Approved Most recent IF: 3.615; 2015 IF: 3.453
Call Number c:irua:126006 Serial 715
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Author Batuk, M.; Buffiere, M.; Zaghi, A.E.; Lenaers, N.; Verbist, C.; Khelifi, S.; Vleugels, J.; Meuris, M.; Hadermann, J.
Title Effect of the burn-out step on the microstructure of the solution-processed Cu(In,Ga)Se2 solar cells Type A1 Journal article
Year 2015 Publication Thin solid films : an international journal on the science and technology of thin and thick films Abbreviated Journal Thin Solid Films
Volume 583 Issue 583 Pages 142-150
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract For the development of the photovoltaic industry cheap methods for the synthesis of Cu(In,Ga)Se-2 (CIGSe) based solar cells are required. In this work, CIGSe thin films were obtained by a solution-based method using oxygen-bearing derivatives. With the aimof improving the morphology of the printed CIGSe layers, we investigated two different annealing conditions of the precursor layer, consisting of (1) a direct selenization step (reference process), and (2) a pre-treatment thermal step prior to the selenization. We showed that the use of an Air/H2S burn-out step prior to the selenization step increases the CIGSe grain size and reduces the carbon content. However, it leads to the reduction of the solar cell efficiency from 4.5% in the reference sample down to 0.5% in the annealed sample. Detailed transmission electron microscopy analysis, including high angle annular dark field scanning transmission electron microscopy and energy dispersive X-ray mapping, was applied to characterize the microstructure of the film and to determine the relationship between microstructure and the solar cell performance. We demonstrated that the relatively low efficiency of the reference solar cells is related not only to the nanosize of the CIGSe grains and presence of the pores in the CIGSe layer, but also to the high amount of secondary phases, namely, In/Ga oxide (or hydroxide) amorphous matter, residuals of organicmatter (carbon), and copper sulfide that is formed at the CIGSe/MoSe2 interface. The annealing in H2S during the burn-out step leads to the formation of the copper sulfide at all grain boundaries and surfaces in the CIGSe layer, which results in the noticeably efficiency drop. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos (up) 000353812400024 Publication Date 2015-04-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0040-6090; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.879 Times cited 5 Open Access
Notes Approved Most recent IF: 1.879; 2015 IF: 1.759
Call Number c:irua:126009 Serial 845
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Author Blandy, J.N.; Abakumov, A.M.; Christensen, K.E.; Hadermann, J.; Adamson, P.; Cassidy, S.J.; Ramos, S.; Free, D.G.; Cohen, H.; Woodruff, D.N.; Thompson, A.L.; Clarke, S.J.;
Title Soft chemical control of the crystal and magnetic structure of a layered mixed valent manganite oxide sulfide Type A1 Journal article
Year 2015 Publication APL materials Abbreviated Journal Apl Mater
Volume 3 Issue 3 Pages 041520
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Oxidative deintercalation of copper ions from the sulfide layers of the layered mixed-valent manganite oxide sulfide Sr2MnO2Cu1.5S2 results in control of the copper-vacancy modulated superstructure and the ordered arrangement of magnetic moments carried by the manganese ions. This soft chemistry enables control of the structures and properties of these complex materials which complement mixed-valent perovskite and perovskite-related transition metal oxides. (C) 2015 Author(s).
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000353828400027 Publication Date 2015-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2166-532X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited 5 Open Access
Notes Approved Most recent IF: 4.335; 2015 IF: NA
Call Number c:irua:126021 Serial 3049
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Author Batuk, M.; Batuk, D.; Tsirlin, A.A.; Filimonov, D.S.; Sheptyakov, D.V.; Frontzek, M.; Hadermann, J.; Abakumov, A.M.
Title Layered oxychlorides [PbBiO2]An+1BnO3n-1Cl2(A = Pb/Bi, B = Fe/Ti) : intergrowth of the hematophanite and sillen phases Type A1 Journal article
Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 27 Issue 27 Pages 2946-2956
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract New layered structures corresponding to the general formula [PbBiO2]A(n+1)B(n)O(3n-1)Cl(2) Were prepared. Pb5BiFe3O10Cl2 (n = 3) and Pb5Bi2Fe4O13Cl2 (n = 4) are built as a stacking of truncated A(n+1)B(n)O(3n-1) perovskite blocks and alpha-PbO-type [A(2)O(2)](2+) (A = Pb, Bi) blocks combined with chlorine sheets. The alternation of these structural blocks can be represented as an intergrowth between the hematophanite and Sullen-type structural blocks. The crystal and-Magnetic structures of Pb5BiFe3O10Cl2 and Pb5Bi2Fe4O13Cl2 were investigated in the temperature range of 1.5-700 K using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy. Both compounds crystallize in the I4/mmm space group with the unit cell parameters a approximate to a(p) approximate to 3.92 angstrom (a unit-cell parameter of the perovskite-structure), c approximate to 43.0 angstrom for the n = 3 member and c approximate to 53.5 angstrom for the n = 4 member. Despite the large separation between the slabs containing the Fe3+ ions (nearly 14 angstrom), long-range antiferromagnetic order sets in below similar to 600 K with the G-type arrangement of the Fe magnetic moments aligned along the c-axis. The possibility of mixing d(0) and d(n) cations at the B sublattice of these structures was also demonstrated by preparing the Ti-substituted n = 4 member Pb6BiFe3TiO13Cl2.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000353865800028 Publication Date 2015-03-26
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 11 Open Access
Notes Approved Most recent IF: 9.466; 2015 IF: 8.354
Call Number c:irua:126060 Serial 1807
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Author Sun, M.; Rousse, G.; Abakumov, A.M.; Saubanere, M.; Doublet, M.-L.; Rodriguez-Carvajal, J.; Van Tendeloo, G.; Tarascon, J.-M.
Title Li2Cu2O(SO4)2: a possible electrode for sustainable Li-based batteries showing a 4.7 V redox activity vs Li+/Li0 Type A1 Journal article
Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 27 Issue 27 Pages 3077-3087
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Li-ion batteries rely on the use of insertion positive electrodes with performances scaling with the redox potential of the 31) metals accompanying Liuptake/removal. Although not commonly studied, the Cu2+/Cu3+ redox potential has been predicted from theoretical calculations to possibly offer a high operating voltage redox couple. We herein report the synthesis and crystal structure of a hitherto-unknown oxysulfate phase, Li2Cu2O(SO4)(2), which contains infinite edgesharing CuO4 chains and presents attractive electrochemical redox activity with respect to Li+/Li, namely amphoteric characteristics. Li2Cu2O(SO4)(2) shows redox activity at 4.7 V vs Li+/Li corresponding to the oxidation of Cu2+ to Cu3+ enlisting ligand holes and associated with the reversible uptake-removal of 0.3 Li. Upon reduction, this compound reversibly uptakes similar to 2 Li at an average potential of about 2.5 V vs Li+/Li, associated with the Cu2+/Cu+ redox couple. The mechanism of the reactivity upon reduction is discussed in detail, with particular attention to the occasional appearance of an oscillation wave in the discharge profile. Our work demonstrates that Cu-based compounds can indeed be fertile scientific ground in the search for new high-energy-density electrodes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000353865800043 Publication Date 2015-03-25
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 20 Open Access
Notes Approved Most recent IF: 9.466; 2015 IF: 8.354
Call Number c:irua:126061 Serial 3541
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Author Javon, E.; Gaceur, M.; Dachraoui, W.; Margeat, O.; Ackermann, J.; Ilenia Saba, M.; Delugas, P.; Mattoni, A.; Bals, S.; Van Tendeloo, G.
Title Competing forces in the self-assembly of coupled ZnO nanopyramids Type A1 Journal article
Year 2015 Publication ACS nano Abbreviated Journal Acs Nano
Volume 9 Issue 9 Pages 3685-3694
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Self-assembly (SA) of nanostructures has recently gained increasing interest. A clear understanding of the process is not straightforward since SA of nanoparticles is a complex multiscale phenomenon including different driving forces. Here, we study the SA between aluminum doped ZnO nanopyramids into couples by combining inorganic chemistry and advanced electron microscopy techniques with atomistic simulations. Our results show that the SA of the coupled nanopyramids is controlled first by morphology, as coupling only occurs in the case of pyramids with well-developed facets of the basal planes. The combination of electron microscopy and atomistic modeling reveals that the coupling is further driven by strong ligandligand interaction between the bases of the pyramids as dominant force, while screening effects due to Al doping or solvent as well as corecore interaction are only minor contributions. Our combined approach provides a deeper understanding of the complex interplay between the interactions at work in the coupled SA of ZnO nanopyramids.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000353867000030 Publication Date 2015-03-12
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 21 Open Access OpenAccess
Notes Esmi; 335078 Colouratom; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 13.942; 2015 IF: 12.881
Call Number c:irua:125978 Serial 434
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Author Warwick, M.E.A.; Kaunisto, K.; Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Sada, C.; Ruoko, T.P.; Turner, S.; Van Tendeloo, G.;
Title Vapor phase processing of \alpha-Fe2O3 photoelectrodes for water splitting : an insight into the structure/property interplay Type A1 Journal article
Year 2015 Publication ACS applied materials and interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 7 Issue 7 Pages 8667-8676
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Harvesting radiant energy to trigger water photoelectrolysis and produce clean hydrogen is receiving increasing attention in the search of alternative energy resources. In this regard, hematite (alpha-Fe2O3) nanostructures with controlled nano-organization have been fabricated and investigated for use as anodes in photoelectrochemical (PEC) cells. The target systems have been grown on conductive substrates by plasma enhanced-chemical vapor deposition (PE-CVD) and subjected to eventual ex situ annealing in air to further tailor their structure and properties. A detailed multitechnique approach has enabled to elucidate between system characteristics and the generated photocurrent. The present alpha-Fe2O3 systems are characterized by a high purity and hierarchical morphologies consisting of nanopyramids/organized dendrites, offering a high contact area with the electrolyte. PEC data reveal a dramatic response enhancement upon thermal treatment, related to a more efficient electron transfer. The reasons underlying such a phenomenon are elucidated and discussed by transient absorption spectroscopy (TAS) studies of photogenerated charge carrier kinetics, investigated on different time scales for the first time on PE-CVD Fe2O3 nanostructures.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000353931300037 Publication Date 2015-04-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244;1944-8252; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited 51 Open Access
Notes 246791 Countatoms; Fwo Approved Most recent IF: 7.504; 2015 IF: 6.723
Call Number c:irua:126059 Serial 3836
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Author Mourdikoudis, S.; Chirea, M.; Zanaga, D.; Altantzis, T.; Mitrakas, M.; Bals, S.; Marzán, L.M.; Pérez-Juste, J.; Pastoriza-Santos, I.
Title Governing the morphology of PtAu heteronanocrystals with improved electrocatalytic performance Type A1 Journal article
Year 2015 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 7 Issue 7 Pages 8739-8747
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Platinumgold heteronanostructures comprising either dimer (PtAu) or coresatellite (Pt@Au) configurations were synthesized by means of a seeded growth procedure using platinum nanodendrites as seeds. Careful control of the reduction kinetics of the gold precursor can be used to direct the nucleation and growth of gold nanoparticles on either one or multiple surface sites simultaneously, leading to the formation of either dimers or coresatellite nanoparticles, respectively, in high yields. Characterization by electron tomography and high resolution electron microscopy provided a better understanding of the actual three-dimensional particle morphology, as well as the AuPt interface, revealing quasi-epitaxial growth of Au on Pt. The prepared PtAu bimetallic nanostructures are highly efficient catalysts for ethanol oxidation in alkaline solution, showing accurate selectivity, high sensitivity, and improved efficiency by generating higher current densities than their monometallic counterparts.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos (up) 000354204400011 Publication Date 2015-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 41 Open Access OpenAccess
Notes 335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number c:irua:126354 Serial 1360
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Author Pittarello, L.; Ji, G.; Yamaguchi, A.; Schryvers, D.; Debaille, V.; Claeys, P.
Title From olivine to ringwoodite : a TEM study of a complex process Type A1 Journal article
Year 2015 Publication Meteoritics and Planetary Science Abbreviated Journal Meteorit Planet Sci
Volume 50 Issue 50 Pages 944-957
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The study of shock metamorphism of olivine might help to constrain impact events in the history of meteorites. Although shock features in olivine are well known, so far, there are processes that are not yet completely understood. In shock veins, olivine clasts with a complex structure, with a ringwoodite rim and a dense network of lamellae of unidentified nature in the core, have been reported in the literature. A highly shocked (S5-6), L6 meteorite, Asuka 09584, which was recently collected in Antarctica by a Belgian-Japanese joint expedition, contains this type of shocked olivine clasts and has been, therefore, selected for detailed investigations of these features by transmission electron microscopy (TEM). Petrographic, geochemical, and crystallographic studies showed that the rim of these shocked clasts consists of an aggregate of nanocrystals of ringwoodite, with lower Mg/Fe ratio than the unshocked olivine. The clast's core consists of an aggregate of iso-oriented grains of olivine and wadsleyite, with higher Mg/Fe ratio than the unshocked olivine. This aggregate is crosscut by veinlets of nanocrystals of olivine, with extremely low Mg/Fe ratio. The formation of the ringwoodite rim is likely due to solid-state, diffusion-controlled, transformation from olivine under high-temperature conditions. The aggregate of iso-oriented olivine and wadsleyite crystals is interpreted to have formed also by a solid-state process, likely by coherent intracrystalline nucleation. Following the compression, shock release is believed to have caused opening of cracks and fractures in olivine and formation of olivine melt, which has lately crystallized under postshock equilibrium pressure conditions as olivine.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000354258400008 Publication Date 2015-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1086-9379; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.391 Times cited 8 Open Access
Notes Approved Most recent IF: 2.391; 2015 IF: 3.104
Call Number c:irua:126058 Serial 1283
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Author Abakumov, M.A.; Nukolova, N.V.; Sokolsky-Papkov, M.; Shein, S.A.; Sandalova, T.O.; Vishwasrao, H.M.; Grinenko, N.F.; Gubsky, I.L.; Abakumov, A.M.; Kabanov, A.V.; Chekhonin, V.P.;
Title VEGF-targeted magnetic nanoparticles for MRI visualization of brain tumor Type A1 Journal article
Year 2015 Publication Nanomedicine: nanotechnology, biology and medicine Abbreviated Journal Nanomed-Nanotechnol
Volume 11 Issue 11 Pages 825-833
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract This work is focused on synthesis and characterization of targeted magnetic nanoparticles as magnetic resonance imaging (MRI) agents for in vivo visualization of gliomas. Ferric oxide (Fe3O4) cores were synthesized by thermal decomposition and coated with bovine serum albumin (BSA) to form nanoparticles with D-eff of 53 +/- 9 nm. The BSA was further cross-linked to improve colloidal stability. Monoclonal antibodies against vascular endothelial growth factor (mAbVEGF) were covalently conjugated to BSA through a polyethyleneglycol linker. Here we demonstrate that 1) BSA coated nanoparticles are stable and non-toxic to different cells at concentration up to 2.5 mg/mL; 2) conjugation of monoclonal antibodies to nanoparticles promotes their binding to VEGF-positive glioma C6 cells in vitro; 3) targeted nanoparticles are effective in MRI visualization of the intracranial glioma. Thus, mAbVEGF-targeted BSA-coated magnetic nanoparticles are promising MRI contrast agents for glioma visualization. (C) 2015 Elsevier Inc. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos (up) 000354559600004 Publication Date 2015-01-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1549-9634; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.72 Times cited 62 Open Access
Notes Approved Most recent IF: 5.72; 2015 IF: 6.155
Call Number c:irua:126351 Serial 3838
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Author van Oeffelen, L.; Van Roy, W.; Idrissi, H.; Charlier, D.; Lagae, L.; Borghs, G.
Title Ion current rectification, limiting and overlimiting conductances in nanopores Type A1 Journal article
Year 2015 Publication PLoS ONE Abbreviated Journal Plos One
Volume 10 Issue 10 Pages e0124171
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Previous reports on Poisson-Nernst-Planck (PNP) simulations of solid-state nanopores have focused on steady state behaviour under simplified boundary conditions. These are Neumann boundary conditions for the voltage at the pore walls, and in some cases also Donnan equilibrium boundary conditions for concentrations and voltages at both entrances of the nanopore. In this paper, we report time-dependent and steady state PNP simulations under less restrictive boundary conditions, including Neumann boundary conditions applied throughout the membrane relatively far away from the nanopore. We simulated ion currents through cylindrical and conical nanopores with several surface charge configurations, studying the spatial and temporal dependence of the currents contributed by each ion species. This revealed that, due to slow co-diffusion of oppositely charged ions, steady state is generally not reached in simulations or in practice. Furthermore, it is shown that ion concentration polarization is responsible for the observed limiting conductances and ion current rectification in nanopores with asymmetric surface charges or shapes. Hence, after more than a decade of collective research attempting to understand the nature of ion current rectification in solid-state nanopores, a relatively intuitive model is retrieved. Moreover, we measured and simulated current-voltage characteristics of rectifying silicon nitride nanopores presenting overlimiting conductances. The similarity between measurement and simulation shows that overlimiting conductances can result from the increased conductance of the electric double-layer at the membrane surface at the depletion side due to voltage-induced polarization charges.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000354916100012 Publication Date 2015-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 11 Open Access
Notes Approved Most recent IF: 2.806; 2015 IF: 3.234
Call Number c:irua:126366 Serial 1744
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Author Egoavil, R.; Huehn, S.; Jungbauer, M.; Gauquelin, N.; Béché, A.; Van Tendeloo, G.; Verbeeck; Moshnyaga, V.
Title Phase problem in the B-site ordering of La2CoMnO6 : impact on structure and magnetism Type A1 Journal article
Year 2015 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 7 Issue 7 Pages 9835-9843
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Epitaxial double perovskite La2CoMnO6 (LCMO) films were grown by metalorganic aerosol deposition on SrTiO3(111) substrates. A high Curie temperature, T-C = 226 K, and large magnetization close to saturation, M-S(5 K) = 5.8 mu(B)/f.u., indicate a 97% degree of B-site (Co,Mn) ordering within the film. The Co/Mn ordering was directly imaged at the atomic scale by scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDX). Local electron-energy-loss spectroscopy (EELS) measurements reveal that the B-sites are predominantly occupied by Co2+ and Mn4+ ions in quantitative agreement with magnetic data. Relatively small values of the (1/2 1/2 1/2) superstructure peak intensity, obtained by X-ray diffraction (XRD), point out the existence of ordered domains with an arbitrary phase relationship across the domain boundary. The size of these domains is estimated to be in the range 35-170 nm according to TEM observations and modelling the magnetization data. These observations provide important information towards the complexity of the cation ordering phenomenon and its implications on magnetism in double perovskites, and similar materials.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos (up) 000354983100060 Publication Date 2015-05-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 37 Open Access
Notes 312483 ESTEEM2; FWO G004413N; 246102 IFOX; Hercules; esteem2_jra3 Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number c:irua:126423 c:irua:126423 Serial 2586
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Author Lin, F.; Meng; Kukueva, E.; Altantzis, T.; Mertens, M.; Bals, S.; Cool, P.; Van Doorslaer, S.
Title Direct-synthesis method towards copper-containing periodic mesoporous organosilicas : detailed investigation of the copper distribution in the material Type A1 Journal article
Year 2015 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 44 Issue 44 Pages 9970-9979
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract Three-dimensional cubic Fm (3) over barm mesoporous copper-containing ethane-bridged PMO materials have been prepared through a direct-synthesis method at room temperature in the presence of cetyltrimethylammonium bromide as surfactant. The obtained materials have been unambiguously characterized in detail by several sophisticated techniques, including XRD, UV-Vis-Dr, TEM, elemental mapping, continuous- wave and pulsed EPR spectroscopy. The results show that at lower copper loading, the Cu2+ species are well dispersed in the Cu-PMO materials, and mainly exist as mononuclear Cu2+ species. At higher copper loading amount, Cu2+ clusters are observed in the materials, but the distribution of the Cu2+ species is still much better in the Cu-PMO materials prepared through the direct-synthesis method than in a Cu-containing PMO material prepared through an impregnation method. Moreover, the evolution of the copper incorporation during the PMO synthesis has been followed by EPR. The results show that the immobilization of the Cu2+ ion/complex and the formation of the PMO materials are taking place simultaneously. The copper ions are found to be situated on the inner surface of the mesopores of the materials and are accessible, which will be beneficial for the catalytic applications.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000355000700028 Publication Date 2015-04-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-9226;1477-9234; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited 11 Open Access OpenAccess
Notes Goa-Bof; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 4.029; 2015 IF: 4.197
Call Number c:irua:126422 Serial 725
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Author Zeng, Y.-J.; Schouteden, K.; Amini, M.N.; Ruan, S.-C.; Lu, Y.-F.; Ye, Z.-Z.; Partoens, B.; Lamoen, D.; Van Haesendonck, C.
Title Electronic band structures and native point defects of ultrafine ZnO nanocrystals Type A1 Journal article
Year 2015 Publication ACS applied materials and interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 7 Issue 7 Pages 10617-10622
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Ultrafine ZnO nanocrystals with a thickness down to 0.25 nm are grown by a metalorganic chemical vapor deposition method. Electronic band structures and native point defects of ZnO nanocrystals are studied by a combination of scanning tunneling microscopy/spectroscopy and first-principles density functional theory calculations. Below a critical thickness of nm ZnO adopts a graphitic-like structure and exhibits a wide band gap similar to its wurtzite counterpart. The hexagonal wurtzite structure, with a well-developed band gap evident from scanning tunneling spectroscopy, is established for a thickness starting from similar to 1.4 nm. With further increase of the thickness to 2 nm, V-O-V-Zn defect pairs are easily produced in ZnO nanocrystals due to the self-compensation effect in highly doped semiconductors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000355055000063 Publication Date 2015-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244;1944-8252; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited 15 Open Access
Notes Hercules; EWI Approved Most recent IF: 7.504; 2015 IF: 6.723
Call Number c:irua:126408 Serial 999
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Author Schutyser, W.; Van den Bosch, S.; Dijkmans, J.; Turner, S.; Meledina, M.; Van Tendeloo, G.; Debecker, D.P.; Sels, B.F.
Title Selective nickel-catalyzed conversion of model and lignin-derived phenolic compounds to cyclohexanone-based polymer building blocks Type A1 Journal article
Year 2015 Publication Chemsuschem Abbreviated Journal Chemsuschem
Volume 8 Issue 8 Pages 1805-1818
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Valorization of lignin is essential for the economics of future lignocellulosic biorefineries. Lignin is converted into novel polymer building blocks through four steps: catalytic hydroprocessing of softwood to form 4-alkylguaiacols, their conversion into 4-alkylcyclohexanols, followed by dehydrogenation to form cyclohexanones, and Baeyer-Villiger oxidation to give caprolactones. The formation of alkylated cyclohexanols is one of the most difficult steps in the series. A liquid-phase process in the presence of nickel on CeO2 or ZrO2 catalysts is demonstrated herein to give the highest cyclohexanol yields. The catalytic reaction with 4-alkylguaiacols follows two parallel pathways with comparable rates: 1) ring hydrogenation with the formation of the corresponding alkylated 2-methoxycyclohexanol, and 2) demethoxylation to form 4-alkylphenol. Although subsequent phenol to cyclohexanol conversion is fast, the rate is limited for the removal of the methoxy group from 2-methoxycyclohexanol. Overall, this last reaction is the rate-limiting step and requires a sufficient temperature (> 250 degrees C) to overcome the energy barrier. Substrate reactivity (with respect to the type of alkyl chain) and details of the catalyst properties (nickel loading and nickel particle size) on the reaction rates are reported in detail for the Ni/CeO2 catalyst. The best Ni/CeO2 catalyst reaches 4-alkylcyclohexanol yields over 80 %, is even able to convert real softwood-derived guaiacol mixtures and can be reused in subsequent experiments. A proof of principle of the projected cascade conversion of lignocellulose feedstock entirely into caprolactone is demonstrated by using Cu/ZrO2 for the dehydrogenation step to produce the resultant cyclohexanones (approximate to 80%) and tin-containing beta zeolite to form 4-alkyl-e-caprolactones in high yields, according to a Baeyer-Villiger-type oxidation with H2O2.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos (up) 000355220300020 Publication Date 2015-04-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1864-5631; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.226 Times cited 71 Open Access
Notes Fwo Approved Most recent IF: 7.226; 2015 IF: 7.657
Call Number c:irua:126406 Serial 2967
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Author Tang, Y.; Chen, Z.; Borbely, A.; Ji, G.; Zhong, S.Y.; Schryvers, D.; Ji, V.; Wang, H.W.
Title Quantitative study of particle size distribution in an in-situ grown Al-TiB2 composite by synchrotron X-ray diffraction and electron microscopy Type A1 Journal article
Year 2015 Publication Materials characterization Abbreviated Journal Mater Charact
Volume 102 Issue 102 Pages 131-136
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Synchrotron X-ray diffraction and transmission electron microscopy (TEM) were applied to quantitatively characterize the average particle size and size distribution of free-standing TiB2 particles and TiB2 particles in an insitu grown Al–TiB2 composite. The detailed evaluations were carried out by X-ray line profile analysis using the restrictedmoment method and multiplewhole profile fitting procedure (MWP). Both numericalmethods indicate that the formed TiB2 particles are well crystallized and free of crystal defects. The average particle size determined from different Bragg reflections by the restricted moment method ranges between 25 and 55 nm, where the smallest particle size is determined using the 110 reflection suggesting the highest lateral-growth velocity of (110) facets. TheMWP method has shown that the in-situ grown TiB2 particles have a very low dislocation density (~1011 m−2) and their size distribution can be described by a log-normal distribution. Good agreement was found between the results obtained from the restricted moment and MWP methods, which was further confirmed by TEM.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos (up) 000355335200017 Publication Date 2015-03-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.714 Times cited 41 Open Access
Notes This work is financially supported by the National Natural Science Foundation of China (Grant No. 51201099 and No. 51301108) and the China Postdoctoral Science Foundation (Grant No. 2013T60443 and No. 2012M520891). The authors are grateful for the project 2013BB03 supported by NPL, CAEP. Many thanks are also due to the faculty of BL14B beamline at the Shanghai Synchrotron Radiation Facility for their help on synchrotron experiments. Approved Most recent IF: 2.714; 2015 IF: 1.845
Call Number c:irua:126443 Serial 2764
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Author McCalla, E.; Prakash, A.S.; Berg, E.; Saubanere, M.; Abakumov, A.M.; Foix, D.; Klobes, B.; Sougrati, M.T.; Rousse, G.; Lepoivre, F.; Mariyappan, S.; Doublet, M.L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Hermann, R.P.; Tarascon, J.M.;
Title Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials Type A1 Journal article
Year 2015 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 162 Issue 162 Pages A1341-A1351
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000355643700030 Publication Date 2015-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651;1945-7111; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited 23 Open Access
Notes Approved Most recent IF: 3.259; 2015 IF: 3.266
Call Number c:irua:126445 Serial 2903
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Author Tyablikov, O.A.; Batuk, D.; Tsirlin, A.A.; Batuk, M.; Verchenko, V.Y.; Filimonov, D.S.; Pokholok, K.V.; Sheptyakov, D.V.; Rozova, M.G.; Hadermann, J.; Antipov, E.V.; Abakumov, A.M.;
Title {110}-Layered B-cation ordering in the anion-deficient perovskite Pb2.4Ba2.6Fe2Sc2TiO13 with the crystallographic shear structure Type A1 Journal article
Year 2015 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 44 Issue 44 Pages 10753-10762
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A novel anion-deficient perovskite-based compound, Pb2.4Ba2.6Fe2Sc2TiO13, was synthesized via the citrate-based route. This compound is an n = 5 member of the A(n)B(n)O(3n-2) homologous series with unit-cell parameters related to the perovskite subcell a(p) approximate to 4.0 angstrom as a(p)root 2 x a(p) x 5a(p)root 2. The crystal structure of Pb2.4Ba2.6Fe2Sc2TiO13 consists of quasi-2D perovskite blocks with a thickness of three octahedral layers separated by the 1/2[110]((1) over bar 01)(p) crystallographic shear (CS) planes, which are parallel to the {110} plane of the perovskite subcell. The CS planes transform the corner-sharing octahedra into chains of edge-sharing distorted tetragonal pyramids. Using a combination of neutron powder diffraction, Fe-57 Mossbauer spectroscopy and atomic resolution electron energy-loss spectroscopy we demonstrate that the B-cations in Pb2.4Ba2.6Fe2Sc2TiO13 are ordered along the {110} perovskite layers with Fe3+ in distorted tetragonal pyramids along the CS planes, Ti4+ preferentially in the central octahedra of the perovskite blocks and Sc3+ in the outer octahedra of the perovskite blocks. Magnetic susceptibility and Mossbauer spectroscopy indicate a broadened magnetic transition around T-N similar to 45 K and the onset of local magnetic fields at low temperatures. The magnetic order is probably reminiscent of that in other A(n)B(n)O(3n-2) homologues, where G-type AFM order within the perovskite blocks has been observed.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000355701000026 Publication Date 2015-01-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-9226;1477-9234; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited 1 Open Access
Notes Approved Most recent IF: 4.029; 2015 IF: 4.197
Call Number c:irua:127001 Serial 22
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Author Delmelle, R.; Amin-Ahmadi, B.; Sinnaeve, M.; Idrissi, H.; Pardoen, T.; Schryvers, D.; Proost, J.
Title Effect of structural defects on the hydriding kinetics of nanocrystalline Pd thin films Type A1 Journal article
Year 2015 Publication International journal of hydrogen energy Abbreviated Journal Int J Hydrogen Energ
Volume 40 Issue 40 Pages 7335-7347
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract While the microstructure of a metal is well-known to affect its equilibrium hydrogen uptake and therefore the hydriding thermodynamics, microstructural effects on the hydriding kinetics are much less documented. Moreover, for thin film systems, such microstructural effects are difficult to separate from the internal stress effect, since most defects generate internal stresses. Such a decoupling has been achieved in this paper for nanocrystalline Pd thin film model systems through the use of a high-resolution, in-situ curvature measurement set-up during Pd deposition, annealing and hydriding. This set-up allowed producing Pd thin films with similar internal stress levels but significantly different microstructures. This was evidenced from detailed defect statistics obtained by transmission electron microscopy, which showed that the densities of grain boundaries, dislocations and twin boundaries have all been lowered by annealing. The same set-up was then used to study the hydriding equilibrium and kinetic behaviour of the resulting films at room temperature. A full quantitative analysis of their hydriding cycles showed that the rate constants of both the adsorption- and absorption-limited kinetic regimes were strongly affected by microstructure. Defect engineering was thereby shown to increase the rate constants for hydrogen adsorption and absorption in Pd by a factor 40 and 30, respectively. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos (up) 000355884300012 Publication Date 2015-05-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0360-3199; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.582 Times cited 13 Open Access
Notes Iap 7/21 Approved Most recent IF: 3.582; 2015 IF: 3.313
Call Number c:irua:126429 Serial 838
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Author Vidick, D.; Ke, X.; Devillers, M.; Poleunis, C.; Delcorte, A.; Moggi, P.; Van Tendeloo, G.; Hermans, S.
Title Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers Type A1 Journal article
Year 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 (up) 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 La Porta, A.; Sanchez-Iglesias, A.; Altantzis, T.; Bals, S.; Grzelczak, M.; Liz-Marzan, L.M.
Title Multifunctional self-assembled composite colloids and their application to SERS detection Type A1 Journal article
Year 2015 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 7 Issue 7 Pages 10377-10381
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We present a simple method for the co-encapsulation of gold nanostars and iron-oxide nanoparticles into hybrid colloidal composites that are highly responsive to both light and external magnetic fields. Self-assembly was driven by hydrophobic interactions between polystyrene capped gold nanostars and iron oxide nanocrystals stabilized with oleic acid, upon addition of water. A block copolymer was then used to encapsulate the resulting spherical colloidal particle clusters, which thereby became hydrophilic. Electron microscopy analysis unequivocally shows that each composite particle comprises a single Au nanostar surrounded by a few hundreds of iron oxide nanocrystals. We demonstrate that this hybrid colloidal system can be used as an efficient substrate for surface enhanced Raman scattering, using common dyes as model molecular probes. The co-encapsulation of iron oxide nanoparticles renders the system magnetically responsive, so that application of an external magnetic field leads to particle accumulation and limits of detection are in the nM range.
Address A1 Article; Electron microscopy for materials research (EMAT);
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos (up) 000355987300010 Publication Date 2015-04-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 51 Open Access OpenAccess
Notes 267867 Plasmaquo; 335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number c:irua:127003 Serial 3940
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Author 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 (up) 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 Most recent IF: 12.124; 2015 IF: 11.805
Call Number c:irua:126430 Serial 1976
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Author Sheng, X.; Daems, N.; Geboes, B.; Kurttepeli, M.; Bals, S.; Breugelmans, T.; Hubin, A.; Vankelecom, I.F.J.; Pescarmona, P.P.
Title N-doped ordered mesoporous carbons prepared by a two-step nanocasting strategy as highly active and selective electrocatalysts for the reduction of O2 to H2O2 Type A1 Journal article
Year 2015 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ
Volume 176-177 Issue 176-177 Pages 212-224
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract A new, two-step nanocasting method was developed to prepare N-doped ordered mesoporous carbon (NOMC) electrocatalysts for the reduction of O2 to H2O2. Our strategy involves the sequential pyrolysis of two inexpensive and readily available N and C precursors, i.e. aniline and dihydroxynaphthalene (DHN), inside the pores of a SBA-15 hard silica template to obtain N-doped graphitic carbon materials with well-ordered pores and high surface areas (764 and 877 m2g−1). By tuning the ratio of carbon sources to silica template, it was possible to achieve an optimal filling of the pores of the SBA-15 silica and to minimise carbon species outside the pores. These NOMC materials displayed outstanding electrocatalytic activity in the oxygen reduction reaction, achieving a remarkably enhanced kinetic current density compared to state-of-the-art N-doped carbon materials (−16.7 mA cm−2 at −0.35 V vs. Ag/AgCl in a 0.1 M KOH solution as electrolyte). The NOMC electrocatalysts showed high selectivity toward the two-electron reduction of oxygen to hydrogen peroxide and excellent long-term stability.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000356549200022 Publication Date 2015-04-05
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 111 Open Access OpenAccess
Notes 335078 Colouratom; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 9.446; 2015 IF: 7.435
Call Number c:irua:125370 Serial 2246
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Author Van Gompel, M.; Atalay, A.Y.; Gaulke, A.; Van Bael, M.K.; D'Haen, J.; Turner, S.; Van Tendeloo, G.; Vanacken, J.; Moshchalkov, V.V.; Wagner, P.
Title Morphological TEM studies and magnetoresistance analysis of sputtered Al-substituted ZnO films : the role of oxygen Type A1 Journal article
Year 2015 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume 212 Issue 212 Pages 1191-1201
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this article, we report on the synthesis of thin, epitaxial films of the transparent conductive oxide Al:ZnO on (0001)-oriented synthetic sapphire substrates by DC sputtering from targets with a nominal 1 at.% Al substitution. The deposition was carried out at an unusually low substrate temperature of only 250 °C in argonoxygen mixtures as well as in pure argon. The impact of the processgas composition on the morphology was analysed by transmission electron microscopy, revealing epitaxial growth in all the cases with a minor impact of the process parameters on the resulting grain sizes. The transport properties resistivity, Hall effect and magnetoresistance were studied in the range from 10 to 300 K in DC and pulsed magnetic fields up to 45 T. While the carrier density and mobility are widely temperature independent, we identified a low fieldlow temperature regime in which the magnetoresistance shows an anomalous, negative behaviour. At higher fields and temperatures, the magnetoresistance exhibits a more conventional, positive curvature with increasing field strength. As a possible explanation, we propose carrier scattering at localised magnetic trace impurities and magnetic correlations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000356706500003 Publication Date 2015-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300; ISBN Additional Links UA library record; WoS full record
Impact Factor 1.775 Times cited Open Access
Notes Methusalem project NANO; FWO; 246791 COUNTATOMS Approved Most recent IF: 1.775; 2015 IF: 1.616
Call Number c:irua:126732 Serial 2204
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Author Pinheiro, C.B.; Abakumov, A.M.
Title Superspace crystallography : a key to the chemistry and properties Type A1 Journal article
Year 2015 Publication IUCrJ Abbreviated Journal Iucrj
Volume 2 Issue 2 Pages 137-154
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An overview is given of the recent advances in the field of modulated molecular and inorganic crystals with an emphasis on the links between incommensurability, intermolecular and interatomic interactions and, wherever possible, the properties of the materials. The importance of detailed knowledge on the modulated structure for understanding the crystal chemistry and the functional properties of modulated phases is shown using selected examples of incommensurate modulations in organic molecular compounds and inorganic complex oxides.
Address
Corporate Author Thesis
Publisher Int union crystallography Place of Publication Chester Editor
Language Wos (up) 000356865900016 Publication Date 2014-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2052-2525; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.793 Times cited 15 Open Access
Notes Approved Most recent IF: 5.793; 2015 IF: NA
Call Number c:irua:127058 Serial 3382
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