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Author El Shinawi, H.; Bertha, A.; Hadermann, J.; Herranz, T.; Santos, B.; Marco, J.F.; Berry, F.J.; Greaves, C.
  Title Synthesis and characterization of La1+xSr2-xCoMnO7-\delta (x=0,0.2; \delta=0,1) Type A1 Journal article
  Year 2010 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
  Volume 183 Issue 6 Pages 1347-1353
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The n=2 Ruddlesden-Popper phases LaSr(2)CoMnO(7) and La(1 2)Sr(1 8)CoMnO(7) have been synthesized by a sol-gel method The O6-type phases LaSr(2)CoMnO(6) and La(1 2)Sr(1 8)CoMnO(6) were produced by reduction of the 07 phases under a hydrogen atmosphere The materials crystallize in the tetragonal I4/mmm space group with no evidence of long-range cation order in the neutron and electron diffraction data Oxygen vacancies in the reduced materials are located primarily at the common apex of the double perovskite layers giving rise to square pyramidal coordination around cobalt and manganese ions. The oxidation states Co(3+)/Mn(4+) and Co(2+)/Mn(3+) predominate in the as-prepared and reduced materials, respectively The materials are spin glasses at low temperature and the dominant magnetic interactions change from ferro- to antiferromagnetic following reduction (C) 2010 Elsevier Inc All rights reserved
  Address
  Corporate Author Thesis
  Publisher Place of Publication London Editor
  Language Wos (down) 000278750100021 Publication Date 2010-04-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.299 Times cited 5 Open Access
  Notes Approved Most recent IF: 2.299; 2010 IF: 2.261
  Call Number UA @ lucian @ c:irua:99209 Serial 3417
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Author Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hébert, S.
  Title Negative magnetoresistance in a V3+/V4+ mixed valent vanadate Type A1 Journal article
  Year 2010 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
  Volume 96 Issue 23 Pages 232502,1-232502,3
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The magnetotransport and magnetic properties of the PbV6O11 vanadate, crystallizing in the P63mc space group, reveal the existence of a negative magnetoresistance related to its ferromagnetic state (TC ∼ 90 K). The maximum effect is observed at 20 K reaching −30% in 9 T. The structural study of this ceramic reveals a V/Pb ratio smaller than expected from the formula. This is explained by the presence of numerous stacking faults observed by high resolution transmission electron microscopy. The existence of these planar defects acting as resistive barriers along the c axis could be responsible for tunneling magnetoresistance.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos (down) 000278695900045 Publication Date 2010-06-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.411 Times cited Open Access
  Notes Approved Most recent IF: 3.411; 2010 IF: 3.841
  Call Number UA @ lucian @ c:irua:83293 Serial 2291
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Author Lorenz, H.; Zhao, Q.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Klötzer, B.; Rameshan, C.; Penner, S.
  Title Preparation and structural characterization of SnO2 and GeO2 methanol steam reforming thin film model catalysts by (HR)TEM Type A1 Journal article
  Year 2010 Publication Materials chemistry and physics Abbreviated Journal Mater Chem Phys
  Volume 122 Issue 2/3 Pages 623-629
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Structure, morphology and composition of different tin oxide and germanium oxide thin film catalysts for the methanol steam reforming (MSR) reaction have been studied by a combination of (high-resolution) transmission electron microscopy, selected area electron diffraction, dark-field imaging and electron energy-loss spectroscopy. Deposition of the thin films on NaCl(0 0 1) cleavage faces has been carried out by thermal evaporation of the respective SnO2 and GeO2 powders in varying oxygen partial pressures and at different substrate temperatures. Preparation of tin oxide films in high oxygen pressures (10−1 Pa) exclusively resulted in SnO phases, at and above 473 K substrate temperature epitaxial growth of SnO on NaCl(0 0 1) leads to well-ordered films. For lower oxygen partial pressures (10−3 to 10−2 Pa), mixtures of SnO and β-Sn are obtained. Well-ordered SnO2 films, as verified by electron diffraction patterns and energy-loss spectra, are only obtained after post-oxidation of SnO films at temperatures T ≥ 673 K in 105 Pa O2. Preparation of GeOx films inevitably results in amorphous films with a composition close to GeO2, which cannot be crystallized by annealing treatments in oxygen or hydrogen at temperatures comparable to SnO/SnO2. Similarities and differences to neighbouring oxides relevant for selective MSR in the third group of the periodic system (In2O3 and Ga2O3) are also discussed with the aim of cross-correlation in formation of nanomaterials, and ultimately, also catalytic properties.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lausanne Editor
  Language Wos (down) 000278637900054 Publication Date 2010-04-18
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0254-0584; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.084 Times cited 15 Open Access
  Notes Esteem 026019 Approved Most recent IF: 2.084; 2010 IF: 2.356
  Call Number UA @ lucian @ c:irua:83099 Serial 2699
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Author Leroux, F.; Gysemans, M.; Bals, S.; Batenburg, K.J.; Snauwaert, J.; Verbiest, T.; van Haesendonck, C.; Van Tendeloo, G.
  Title Three-dimensional characterization of helical silver nanochains mediated by protein assemblies Type A1 Journal article
  Year 2010 Publication Advanced materials Abbreviated Journal Adv Mater
  Volume 22 Issue 19 Pages 2193-2197
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
  Abstract Characterization methods for the structural investigation of biotemplates for nanodevices remain widely unexplored, despite the fact that biotemplating methods for nanodevice fabrication are becoming more widespread. In this study several techniques are used to characterize the morphology and 3D distribution of silver nanoparticles deposited on insulin fibrils.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos (down) 000278601400016 Publication Date 2010-03-11
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0935-9648;1521-4095; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 19.791 Times cited 51 Open Access
  Notes Esteem 026019; Fwo Approved Most recent IF: 19.791; 2010 IF: NA
  Call Number UA @ lucian @ c:irua:83296 Serial 3645
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Author Yiu, H.H.P.; Niu, H.-jun; Biermans, E.; Van Tendeloo, G.; Rosseinsky, M.J.
  Title Designed multifunctional nanocomposites for biomedical applications Type A1 Journal article
  Year 2010 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
  Volume 20 Issue 10 Pages 1599-1609
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The assembly of multifunctional nanocomposite materials is demonstrated by exploiting the molecular sieving property of SBA-16 nanoporous silica and using it as a template material. The cages of the pore networks are used to host iron oxide magnetic nanoparticles, leaving a pore volume of 0.29 cm3 g-1 accessible for drug storage. This iron oxide-silica nanocomposite is then functionalized with amine groups. Finally the outside of the particle is decorated with antibodies. Since the size of many protein molecules, including that of antibodies, is too large to enter the pore system of SBA-16, the amine groups inside the pores are preserved for drug binding. This is proven using a fluorescent protein, fluorescein-isothiocyanate-labeled bovine serum albumin (FITC-BSA), with the unreacted amine groups inside the pores dyed with rhodamine B isothiocyanate (RITC). The resulting nanocomposite material offers a dual-targeting drug delivery mechanism, i.e., magnetic and antibody-targeting, while the functionalization approach is extendable to other applications, e.g., fluorescence-magnetic dual-imaging diagnosis.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos (down) 000278597100008 Publication Date 2010-04-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1616-301X;1616-3028; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 56 Open Access
  Notes Approved Most recent IF: 12.124; 2010 IF: 8.508
  Call Number UA @ lucian @ c:irua:83298 Serial 662
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Author Amin-Ahmadi, B.; Aashuri, H.
  Title Globular structure of M2 high speed steel by thermomechanical treatment in the semisolid state Type A1 Journal article
  Year 2010 Publication Steel research international Abbreviated Journal Steel Res Int
  Volume 81 Issue 5 Pages 381-386
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The globular structure of M2 high speed steel in the rolled – annealed and as cast conditions was investigated in the semisolid state. Metallographic observations resulted in globular austenite particles that were surrounded by a liquid phase. Dissolution of various carbides in the austenite phase at semisolid temperatures led to grain boundary liquation and formation of near-spherical solid grains in a liquid matrix. Therefore, at the semisolid state, the solid particles were free from carbides. MC- type and M6C- type eutectic carbides re- precipitated at the grain boundaries during cooling of the samples from the semisolid temperature. The variation of shape factor versus holding time and holding temperature was examined. A transition value for shape factor changes in high speed steels was achieved. The growth rate constants of the Ostwald ripening and the coalescence mechanisms were calculated by using the experimentally determined rate constant. It was observed that less liquid droplets were enclosed inside the solid particles compared with non-ferrous alloys. Besides, it has been shown that at high solid fraction, the Ostwald ripening mechanism plays a prominent role in the coarsening phenomenon in comparison with the coalescence mechanism. Grains can rotate and arrange low misorientation with each other at high liquid contents, therefore low energetic grain boundaries form between these grains. These grain boundaries play an important role in the coalescence mechanism.
  Address
  Corporate Author Thesis
  Publisher Verlag Stahleisen Place of Publication Düsseldorf Editor
  Language Wos (down) 000278292200007 Publication Date 2010-05-18
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1611-3683;1869-344X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.235 Times cited 1 Open Access
  Notes Approved Most recent IF: 1.235; 2010 IF: 0.455
  Call Number UA @ lucian @ c:irua:122047 Serial 1347
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Author O'Regan, T.P.; Hurley, P.K.; Sorée, B.; Fischetti, M.V.
  Title Modeling the capacitance-voltage response of In0.53Ga0.47As metal-oxide-semiconductor structures : charge quantization and nonparabolic corrections Type A1 Journal article
  Year 2010 Publication Applied Physics Letters Abbreviated Journal Appl Phys Lett
  Volume 96 Issue 21 Pages 213514,1-213514,3
  Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
  Abstract The capacitance-voltage (C-V) characteristic is calculated for p-type In<sub>0.53</sub>Ga<sub>0.47</sub>As metal-oxide-semiconductor (MOS) structures based on a self-consistent PoissonSchrödinger solution. For strong inversion, charge quantization leads to occupation of the satellite valleys which appears as a sharp increase in the capacitance toward the oxide capacitance. The results indicate that the charge quantization, even in the absence of interface defects (D<sub>it</sub>), is a contributing factor to the experimental observation of an almost symmetric C-V response for In<sub>0.53</sub>Ga<sub>0.47</sub>As MOS structures. In addition, nonparabolic corrections are shown to enhance the depopulation of the Γ valley, shifting the capacitance increase to lower inversion charge densities.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos (down) 000278183200090 Publication Date 2010-05-28
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.411 Times cited 26 Open Access
  Notes Approved Most recent IF: 3.411; 2010 IF: 3.841
  Call Number UA @ lucian @ c:irua:89509 Serial 2143
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Author Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H.
  Title Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 17 Pages 174424,1-174424,13
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 000278141600082 Publication Date 2010-05-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 27 Open Access
  Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:83384 Serial 1294
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Author Nistor, S.V.; Stefan, M.; Nistor, L.C.; Goovaerts, E.; Van Tendeloo, G.
  Title Incorporation and localization of substitutional Mn2+ ions in cubic ZnS quantum dots Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 3 Pages 035336,1-035336,6
  Keywords A1 Journal article; Nanostructured and organic optical and electronic materials (NANOrOPT); Electron microscopy for materials research (EMAT)
  Abstract Multifrequency electron paramagnetic resonance (EPR) and high resolution transmission electron microscopy (HRTEM) investigations were performed on small (2 nm) cubic ZnS nanocrystals (quantum dotsQDs) doped with 0.2% mol Mn2+, self-assembled into a mesoporous structure. The EPR data analysis shows that the substitutional Mn2+ ions are localized at Zn2+ sites subjected to a local axial lattice distortion, resulting in the observed zero-field-splitting parameter |D|=41×10−4 cm−1. The local distortion is attributed to the presence in the second shell of ligands of a stacking fault or twin, which alters the normal stacking sequence of the cubic structure. The HRTEM results confirm the presence of such extended planar defects in a large percentage of the investigated QDs, which makes possible the proposed substitutional Mn2+ impurity ions localization model. Based on these results it is suggested that the high doping levels of Mn2+ ions observed in cubic ZnS and possible in other II-VI semiconductor QDs prepared at low temperatures can be explained by the assistance of the extended lattice defects in the impurities incorporation.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 000277970900007 Publication Date 2010-01-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 55 Open Access
  Notes Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:83649 Serial 1597
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Author Poltavets, V.V.; Lokshin, K.A.; Nevidomskyy, A.H.; Croft, M.; Tyson, T.A.; Hadermann, J.; Van Tendeloo, G.; Egami, T.; Kotliar, G.; ApRoberts-Warren, N.; Dioguardi, A.P.; Curro, N.J.; Greenblatt, M.;
  Title Bulk magnetic order in a two-dimensional Ni1+/Ni2+ (d9/d8) nickelate, isoelectronic with superconducting cuprates Type A1 Journal article
  Year 2010 Publication Physical review letters Abbreviated Journal Phys Rev Lett
  Volume 104 Issue 20 Pages 206403
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The Ni(1+)/Ni(2+) states of nickelates have the identical (3d(9)/3d(8)) electronic configuration as Cu(2+)/Cu(3+) in the high temperature superconducting cuprates, and are expected to show interesting properties. An intriguing question is whether mimicking the electronic and structural features of cuprates would also result in superconductivity in nickelates. Here we report experimental evidence for a bulklike magnetic transition in La(4)Ni(3)O(8) at 105 K. Density functional theory calculations relate the transition to a spin density wave nesting instability of the Fermi surface.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos (down) 000277945900033 Publication Date 2010-05-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.462 Times cited 35 Open Access
  Notes Approved Most recent IF: 8.462; 2010 IF: 7.622
  Call Number UA @ lucian @ c:irua:95613 Serial 260
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Author Schattschneider, P.; Ennen, I.; Stoger-Pollach, M.; Verbeeck, J.
  Title Circular dichroism in the electron microscope: progress and applications (invited) Type A1 Journal article
  Year 2010 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 107 Issue 9 Pages 09d311,1-09d311,6
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract According to theory, x-ray magnetic circular dichroism in a synchrotron is equivalent to energy loss magnetic chiral dichroism (EMCD) in a transmission electron microscope (TEM). After a synopsis of the development of EMCD, the theoretical background is reviewed and recent results are presented, focusing on the study of magnetic nanoparticles for ferrofluids and Heusler alloys for spintronic devices. Simulated maps of the dichroic strength as a function of atom position in the crystal allow evaluating the influence of specimen thickness and sample tilt on the experimental EMCD signal. Finally, the possibility of direct observation of chiral electronic transitions with atomic resolution in a TEM is discussed.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos (down) 000277834300276 Publication Date 2010-05-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 28 Open Access
  Notes Esteem Approved Most recent IF: 2.068; 2010 IF: 2.079
  Call Number UA @ lucian @ c:irua:83653UA @ admin @ c:irua:83653 Serial 361
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Author Li, Y.; Yang, X.-Y.; Tian, G.; Vantomme, A.; Yu, J.; Van Tendeloo, G.; Su, B.-L.
  Title Chemistry of trimethyl aluminum: a spontaneous route to thermally stable 3D crystalline macroporous alumina foams with a hierarchy of pore sizes Type A1 Journal article
  Year 2010 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 22 Issue 10 Pages 3251-3258
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract A simple and spontaneous one-pot self-formation procedure that is easy to scale up has been developed based on the chemistry of trimethylaluminum (TMA), leading to thermally stable macroporous crystalline alumina with a very unique and unprecedented three-dimensional (3D) hierarchical pore structure consisting of well-defined wormlike mesopores. TMA is the precursor of both product and porogene (viz, two working functions within the same molecule (2 in 1)). The materials obtained have been intensively characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), N2 adsorption−desorption, and mercury porosimetry. The open cagelike macrocavities are self-constructed by mesoporous nanorods (diameter of ca. 40−70 nm), which are themselves formed by a random assembly of fibrous nanoparticles 5−6 nm in size. Optical microscopy (OM) has been used in situ to follow the synthesis procedure, which led to the proposal of the formation mechanism. Methane molecules as porogens, which were instantaneously released because of the fast hydrolysis of the chemical precursor, were the key factor in producing these 3D structures with uniform co-continuous macropores that interconnected directly with the wormlike mesopores. The important characteristic of this procedure is the concurrent formation of a multiscaled porous network. The material exhibits great thermal stability. The hierarchically mesoporous−macroporous Al2O3 obtained is quite attractive for a myriad of applications, from catalysis to biomedicine. The present work illustrates that the one-pot self-formation concept, based on the chemistry of alkyl metals, is a versatile method to design industrially valuable hierarchically porous materials.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos (down) 000277635000030 Publication Date 2010-04-27
  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 38 Open Access
  Notes Approved Most recent IF: 9.466; 2010 IF: 6.400
  Call Number UA @ lucian @ c:irua:82760 Serial 356
Permanent link to this record
 

 
Author Jorissen, K.; Rehr, J.J.; Verbeeck, J.
  Title Multiple scattering calculations of relativistic electron energy loss spectra Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 15 Pages 155108,1-155108,6
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract A generalization of the real-space Greens-function approach is presented for ab initio calculations of relativistic electron energy loss spectra (EELS) which are particularly important in anisotropic materials. The approach incorporates relativistic effects in terms of the transition tensor within the dipole-selection rule. In particular, the method accounts for relativistic corrections to the magic angle in orientation resolved EELS experiments. The approach is validated by a study of the graphite C  K edge, for which we present an accurate magic angle measurement consistent with the predicted value.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 000277210500038 Publication Date 2010-04-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 24 Open Access
  Notes Fwo; Esteem 026019 Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:82805UA @ admin @ c:irua:82805 Serial 2230
Permanent link to this record
 

 
Author Nourbakhsh, A.; Cantoro, M.; Klekachev, A.; Clemente, F.; Sorée, B.; van der Veen, M.H.; Vosch, T.; Stesmans, A.; Sels, B.; de Gendt, S.
  Title Tuning the Fermi level of SiO2-supported single-layer graphene by thermal annealing Type A1 Journal article
  Year 2010 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
  Volume 114 Issue 5 Pages 6894-6900
  Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
  Abstract The effects of thermal annealing in inert Ar gas atmosphere of SiO2-supported, exfoliated single-layer graphene are investigated in this work. A systematic, reproducible change in the electronic properties of graphene is observed after annealing. The most prominent Raman features in graphene, the G and 2D peaks, change in accord to what is expected in the case of hole doping. The results of electrical characterization performed on annealed, back-gated field-effect graphene devices show that the neutrality point voltage VNP increases monotonically with the annealing temperature, confirming the occurrence of excess hole accumulation. No degradation of the structural properties of graphene is observed after annealing at temperatures as high as 400 °C. Thermal annealing of single-layer graphene in controlled Ar atmosphere can therefore be considered a technique to reproducibly modify the electronic structure of graphene by tuning its Fermi level.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos (down) 000276562500002 Publication Date 2010-03-26
  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 54 Open Access
  Notes Approved Most recent IF: 4.536; 2010 IF: 4.524
  Call Number UA @ lucian @ c:irua:89508 Serial 3757
Permanent link to this record
 

 
Author Vassiliev, S.Y.; Laurinavichute, V.K.; Abakumov, A.M.; Govorov, V.A.; Bendovskii, E.B.; Turner, S.; Filatov, A.Y.; Tarasovskii, V.P.; Borzenko, A.G.; Alekseeva, A.M.; Antipov, E.V.
  Title Microstructural aspects of the degradation behavior of SnO2-based anodes for aluminum electrolysis Type A1 Journal article
  Year 2010 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
  Volume 157 Issue 5 Pages C178-C186
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The performance of SnO2 ceramic anodes doped with copper and antimony oxides was examined in cryolite alumina melts under anodic polarization at different cryolite ratios, temperatures, times, and current densities. The corroded part consists of a narrow strong corrosion zone at the anode surface with damage of the intergrain contacts and a large increase in porosity, a wider moderate corrosion zone with a smaller porosity increase, and a Cu depletion zone, where the ceramic retains its initial microstructure and a slight porosity increase occurs due to the removal of the Cu-rich inclusions. Mechanical destruction of the anode was never observed in the 10100 h tests. A microstructural model of the ceramic was suggested, consisting of grains with an Sb-doped SnO2 grain core surrounded by an ~200 to 500 nm grain shell where SnO2 was simultaneously doped with Sb and Mn+ (M=Cu2+,Fe3+,Al3+). The grains were separated by a few nanometers thick Cu-enriched grain boundaries. Different secondary charge carrier (holes) concentrations and electric conductivities in the grain core and grain shell result in a higher current density at the intergrain regions that leads to their profound degradation, especially in the low temperature acidic melt.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos (down) 000276555300037 Publication Date 2010-04-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0013-4651; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.259 Times cited 3 Open Access
  Notes Approved Most recent IF: 3.259; 2010 IF: 2.427
  Call Number UA @ lucian @ c:irua:82260 Serial 2040
Permanent link to this record
 

 
Author Idrissi, H.; Renard, K.; Ryelandt, L.; Schryvers, D.; Jacques, P.J.
  Title On the mechanism of twin formation in FeMnC TWIP steels Type A1 Journal article
  Year 2010 Publication Acta materialia Abbreviated Journal Acta Mater
  Volume 58 Issue 7 Pages 2464-2476
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Although it is well known that FeMnC TWIP steels exhibit high work-hardening rates, the elementary twinning mechanisms controlling the plastic deformation of these steels have still not been characterized. The aim of the present study is to analyse the extended defects related to the twinning occurrence using transmission electron microscopy. Based on these observations, the very early stage of twin nucleation can be attributed to the pole mechanism with deviation proposed by Cohen and Weertman or to the model of Miura, Takamura and Narita, while the twin growth is controlled by the pole mechanism proposed by Venables. High densities of sessile Frank dislocations are observed within the twins at the early stage of deformation, which can affect the growth and the stability of the twins, but also the strength of these twins and their interactions with the gliding dislocations present in the matrix. This experimental evidence is discussed and compared to recent results in order to relate the defects analysis to the macroscopic behaviour of this category of material.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Oxford Editor
  Language Wos (down) 000276523200018 Publication Date 2010-01-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1359-6454; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 5.301 Times cited 244 Open Access
  Notes Iap Approved Most recent IF: 5.301; 2010 IF: 3.791
  Call Number UA @ lucian @ c:irua:82270 Serial 2441
Permanent link to this record
 

 
Author Isaeva, A.A.; Makarevich, O.N.; Kutznetsov, A.N.; Doert, T.; Abakumov, A.M.; Van Tendeloo, G.
  Title Mixed tellurides Ni3-xGaTe2 (0\leq x\leq0.65): crystal and electronic structures, properties, and nickel deficiency effects on vacancy ordering Type A1 Journal article
  Year 2010 Publication European journal of inorganic chemistry Abbreviated Journal Eur J Inorg Chem
  Volume Issue 9 Pages 1395-1404
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The Ni3-xGaTe2 series of compounds (0 x 0.65) was synthesized by a high-temperature ceramic technique at 750 °C. Crystal structures of three compounds in the series were determined by X-ray powder diffraction: Ni2.98(1)GaTe2 (RI = 0.042, Rp = 0.023, Rwp = 0.035), Ni2.79(1)GaTe2 (RI = 0.053, Rp = 0.028, Rwp = 0.039), Ni2.58(1)GaTe2 (RI = 0.081, Rp = 0.037, Rwp = 0.056); the structures were verified by electron diffraction and, for the former compound, high-resolution electron microscopy. The compounds crystallize in a hexagonal lattice with P63/mmc, and the structures can be regarded as a hexagonal close-packed array with a -Ga-Te-Te- stacking sequence. The octahedral and trigonal bipyramidal voids in the hcp structure are selectively filled with Ni atoms to form one entirely occupied and two partially occupied sites, thus allowing variations in the nickel content in the series of compounds Ni3-xGaTe2 (0 x 0.65). A superstructure with asup = 2asub (P63/mmc) has been identified for Ni3-xGaTe2 (0.5 x 0.65) by electron diffraction. Real-space, high-resolution images confirm an ordering of Ni atoms and vacancies inthe ab plane. Quantum-chemical calculations performed forNi3-xGaTe2 (x = 0, 0.25, 0.75, 1) suggest anisotropic metallic conductivity and Pauli paramagnetic behavior that are experimentally confirmed for Ni3GaTe2.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos (down) 000276370300009 Publication Date 2010-02-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1434-1948;1099-0682; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.444 Times cited 8 Open Access
  Notes Approved Most recent IF: 2.444; 2010 IF: 2.910
  Call Number UA @ lucian @ c:irua:82266 Serial 2090
Permanent link to this record
 

 
Author Xu, T.; Nys, J.-P.; Addad, A.; Lebedev, O.I.; Urbieta, A.; Salhi, B.; Berthe, M.; Grandidier, B.; Stievenard, D.
  Title Faceted sidewalls of silicon nanowires: Au-induced structural reconstructions and electronic properties Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 11 Pages 115403,1-115403,10
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Si nanowires with a ⟨111⟩ orientation, synthesized by vapor-liquid-solid process with low silane partial pressure reactant and gold as the catalyst, are known to exhibit sawtooth facets containing gold adsorbates. We report herein the study of the nanowire morphology by means of transmission electron microscopy and scanning tunneling microscopy. The nanowires consist of faceted sidewalls. The number of the sidewalls changes from 12 to 6 along the growth axis, giving rise to nanowires with an irregular hexagonal cross section at their base. The sidewalls are covered with Au-rich clusters. Their facets also exhibit atomic structures that reveal the presence of gold, resulting from the diffusion of gold during the growth. Based on these observations, the tapering of the nanowire is found to be related to two contributions: the reduction in the catalyst particle size during the growth and lateral overgrowth from the direct incorporation of Si species onto the nanowire sidewalls. Because the rearrangement of atoms at surfaces and interfaces might affect the growth kinetics, the trigonal symmetry as well as the higher lateral growth rate on the widest sidewalls are explained from the existence of an interfacial atomic structure with two inequivalent parts in the unit cell. Finally, spectroscopic measurements were performed on the major facets and revealed a metallic behavior at 77 K.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 000276248800116 Publication Date 2010-03-03
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 42 Open Access
  Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:82273 Serial 1168
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Author Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G.
  Title Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process Type A1 Journal article
  Year 2010 Publication Crystal growth & design Abbreviated Journal Cryst Growth Des
  Volume 10 Issue 4 Pages 2011-2018
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 000276234500080 Publication Date 2010-03-18
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1528-7483;1528-7505; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.055 Times cited 75 Open Access
  Notes Esteem 026019 Approved Most recent IF: 4.055; 2010 IF: 4.390
  Call Number UA @ lucian @ c:irua:82311 Serial 1472
Permanent link to this record
 

 
Author Ke, X.; Bals, S.; Cott, D.; Hantschel, T.; Bender, H.; Van Tendeloo, G.
  Title Three-dimensional analysis of carbon nanotube networks in interconnects by electron tomography without missing wedge artifacts Type A1 Journal article
  Year 2010 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
  Volume 16 Issue 2 Pages 210-217
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The three-dimensional (3D) distribution of carbon nanotubes (CNTs) grown inside semiconductor contact holes is studied by electron tomography. The use of a specialized tomography holder results in an angular tilt range of ±90°, which means that the so-called missing wedge is absent. The transmission electron microscopy (TEM) sample for this purpose consists of a micropillar that is prepared by a dedicated procedure using the focused ion beam (FIB) but keeping the CNTs intact. The 3D results are combined with energy dispersive X-ray spectroscopy (EDS) to study the relation between the CNTs and the catalyst particles used during their growth. The reconstruction, based on the full range of tilt angles, is compared with a reconstruction where a missing wedge is present. This clearly illustates that the missing wedge will lead to an unreliable interpretation and will limit quantitative studies
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge, Mass. Editor
  Language Wos (down) 000276137200011 Publication Date 2010-02-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.891 Times cited 42 Open Access
  Notes Esteem 026019; Fwo; Iap-Vi Approved Most recent IF: 1.891; 2010 IF: 3.259
  Call Number UA @ lucian @ c:irua:82279 Serial 3642
Permanent link to this record
 

 
Author Afanasov, I.M.; Shornikova, O.N.; Kirilenko, D.A.; Vlasov, I.I.; Zhang, L.; Verbeeck, J.; Avdeev, V.V.; Van Tendeloo, G.
  Title Graphite structural transformations during intercalation by HNO3 and exfoliation Type L1 Letter to the editor
  Year 2010 Publication Carbon Abbreviated Journal Carbon
  Volume 48 Issue 6 Pages 1862-1865
  Keywords L1 Letter to the editor; Electron microscopy for materials research (EMAT)
  Abstract Expandable graphite of two types was synthesized by (1) hydrolysis of graphite nitrate of II stage and (2) anodic polarization of graphite in 60% HNO3. Exfoliated graphite samples were produced by thermal shock of expandable graphite samples in air at 900 °C. A comparative study of microstructural distinctions of both expandable and exfoliated graphite samples was carried out using X-ray diffraction, Raman spectroscopy, electron energy loss spectroscopy and high resolution transmission electron microscopy.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Oxford Editor
  Language Wos (down) 000276132800021 Publication Date 2010-02-02
  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 43 Open Access
  Notes Approved Most recent IF: 6.337; 2010 IF: 4.896
  Call Number UA @ lucian @ c:irua:82315UA @ admin @ c:irua:82315 Serial 1379
Permanent link to this record
 

 
Author Zelaya, E.; Schryvers, D.; Tolley, A.; Fitchner, P.F.P.
  Title Cavity nucleation and growth in Cu-Zn-Al irradiated with Cu+ ions at different temperatures Type A1 Journal article
  Year 2010 Publication Intermetallics Abbreviated Journal Intermetallics
  Volume 18 Issue 4 Pages 493-498
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The effects of high dose ion irradiation in β CuZnAl were investigated between room temperature and 150 °C. Single crystal samples with surface normal close to [001]β were irradiated with 300 keV Cu+ ions. Microstructural changes were characterized using transmission electron microscopy. Irradiation induced cavities located on the surface exposed to the irradiation were observed. The morphology, size and density distribution of these cavities were analyzed as a function of different irradiation conditions. The shape and location of the cavities with respect to the irradiation surface were not affected by irradiation temperature or irradiation dose. Instead, the cavity size distribution showed a bi-modal shape for a dose of 15 dpa, regardless of irradiation temperature. For a dose of 30 dpa the bi-modal distribution was only observed after room temperature irradiation. The diffusion effects of vacancies produced by irradiation are analyzed in shape memory CuZnAl alloys, which main characteristic is the diffusionless martensitic transformation. Particularly, the cavity size distributions were analyzed in terms of nucleation, growth and coalescence.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Chicago, Ill. Editor
  Language Wos (down) 000276058200014 Publication Date 2009-10-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0966-9795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.14 Times cited 1 Open Access
  Notes Iaea Approved Most recent IF: 3.14; 2010 IF: 2.335
  Call Number UA @ lucian @ c:irua:80924 Serial 302
Permanent link to this record
 

 
Author Vlasov, I.I.; Shenderova, O.; Turner, S.; Lebedev, O.I.; Basov, A.A.; Sildos, I.; Rähn, M.; Shiryaev, A.A.; Van Tendeloo, G.
  Title Nitrogen and luminescent nitrogen-vacancy defects in detonation nanodiamond Type A1 Journal article
  Year 2010 Publication Small Abbreviated Journal Small
  Volume 6 Issue 5 Pages 687-694
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract An efficient method to investigate the microstructure and spatial distribution of nitrogen and nitrogen-vacancy (N-V) defects in detonation nanodiamond (DND) with primary particle sizes ranging from approximately 3 to 50 nm is presented. Detailed analysis reveals atomic nitrogen concentrations as high as 3 at% in 50% of diamond primary particles with sizes smaller than 6 nm. A non-uniform distribution of nitrogen within larger primary DND particles is also presented, indicating a preference for location within the defective central part or at twin boundaries. A photoluminescence (PL) spectrum with well-pronounced zero-phonon lines related to the N-V centers is demonstrated for the first time for electron-irradiated and annealed DND particles at continuous laser excitation. Combined Raman and PL analysis of DND crystallites dispersed on a Si substrate leads to the conclusion that the observed N-V luminescence originates from primary particles with sizes exceeding 30 nm. These findings demonstrate that by manipulation of the size/nitrogen content in DND there are prospects for mass production of nanodiamond photoemitters based on bright and stable luminescence from nitrogen-related defects.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos (down) 000275972400013 Publication Date 2010-01-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1613-6810;1613-6829; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.643 Times cited 84 Open Access
  Notes Esteem 026019 Approved Most recent IF: 8.643; 2010 IF: 7.336
  Call Number UA @ lucian @ c:irua:82364 Serial 2341
Permanent link to this record
 

 
Author Philippaerts, A.; Paulussen, S.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Poelman, H.; Bulut, M.; de Clippel, F.; Smeets, P.; Sels, B.; Jacobs, P.
  Title Selectivity in sorption and hydrogenation of methyl oleate and elaidate on MFI zeolites Type A1 Journal article
  Year 2010 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 270 Issue 1 Pages 172-184
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Different zeolites were tested for selective removal of methyl elaidate (trans isomer) from an equimolar mixture with methyl oleate (cis isomer). Sorption experiments of the geometric isomers show that only ZSM-5 samples with reduced Al content in the framework are able to discriminate among the bent cis and the linear trans fatty acid methyl esters. Hydrogenation experiments of equimolar methyl oleate and elaidate mixtures at low temperature (65 °C) and high hydrogen pressure (6.0 MPa), using Pt catalysts, confirm this result. Only with a Pt/NaZSM-5 catalyst outspoken selectivity for the hydrogenation of the trans isomer is obtained. In order to prepare a selective Pt/ZSM-5 catalyst, the influence of Pt addition (impregnation, ion-exchange and competitive ion-exchange) and Pt activation (different calcination and reduction temperatures) on the Pt-distribution and Pt particle size was investigated using SEM, bright-field and HR TEM, EDX, electron tomography, CO-chemisorption, XPS, XRD, and UVvis measurements. The best result in terms of hydrogenation activity and selectivity is obtained with a Pt/ZSM-5 catalyst, which is prepared via competitive ion-exchange, followed by slow calcination up to 350 °C under high O2 flow and a reduction up to 500 °C under H2. This preparation method leads to a Pt/ZSM-5 catalyst with the best Pt distribution and the smallest Pt clusters occluded in the zeolite structure. Finally, the influence of zeolite crystal size, morphology, and elemental composition of ZSM-5 on hydrogenation activity and selectivity was investigated in detail.
  Address
  Corporate Author Thesis
  Publisher Place of Publication San Diego, Calif. Editor
  Language Wos (down) 000275966100021 Publication Date 2010-01-28
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0021-9517; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 24 Open Access
  Notes FWO; IAP-IV; Methusalem Approved Most recent IF: 6.844; 2010 IF: 5.415
  Call Number UA @ lucian @ c:irua:82435 Serial 2970
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Author Suarez-Martinez, I.; Ewels, C.P.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Felten, A.; Pireaux, J.-J.; Ghijsen, J.; Bittencourt, C.
  Title Study of the interface between rhodium and carbon nanotubes Type A1 Journal article
  Year 2010 Publication ACS nano Abbreviated Journal Acs Nano
  Volume 4 Issue 3 Pages 1680-1686
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract X-ray photoelectron spectroscopy at 3.5 keV photon energy, in combination with high-resolution transmission electron microscopy, is used to follow the formation of the interface between rhodium and carbon nanotubes. Rh nucleates at defect sites, whether initially present or induced by oxygen-plasma treatment. More uniform Rh cluster dispersion is observed on plasma-treated CNTs. Experimental results are compared to DFT calculations of small Rh clusters on pristine and defective graphene. While Rh interacts as strongly with the carbon as Ti, it is less sensitive to the presence of oxygen, suggesting it as a good candidate for nanotube contacts.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 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
Permanent link to this record
 

 
Author Verlooy, P.L.H.; Robeyns, K.; van Meervelt, L.; Lebedev, O.I.; Van Tendeloo, G.; Martens, J.A.; Kirschhock, C.E.A.
  Title Synthesis and characterization of the new cyclosilicate hydrate (hexamethyleneimine)4.[Si8O16(OH)4].12H2O Type A1 Journal article
  Year 2010 Publication Microporous and mesoporous materials: zeolites, clays, carbons and related materials Abbreviated Journal Micropor Mesopor Mat
  Volume 130 Issue 1/3 Pages 14-20
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract A new cyclosilicate hydrate with composition (C6H14N)4·[Si8O16(OH)4]·12H2O was crystallized and the structure determined by single-crystal X-ray diffraction. The structure, described by the tetragonal space group I41/a, with unit cell dimensions of a = 39.2150(2) Å and c = 14.1553(2) Å, contains columns of hydrogen-bonded cubic octamer silicate anions. The space between silicate columns holds hydrogen-bonded water and protonated hexamethyleneimine molecules compensating the negative charge of the silicate. The crystal water can be removed resulting in a rearrangement of the columns into orthorhombic symmetry. Removal of the organic moiety causes amorphisation. Flash evacuation results in a new microporous material with pore volumes typical of a zeolite.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos (down) 000275702600003 Publication Date 2009-10-14
  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 Approved Most recent IF: 3.615; 2010 IF: 3.220
  Call Number UA @ lucian @ c:irua:82448 Serial 3418
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Author Zhao, Q.; Lorenz, H.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Rameshan, C.; Klötzer, B.; Konzett, J.; Penner, S.
  Title Catalytic characterization of pure SnO2 and GeO2 in methanol steam reforming Type A1 Journal article
  Year 2010 Publication Applied catalysis : A : general Abbreviated Journal Appl Catal A-Gen
  Volume 375 Issue 2 Pages 188-195
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Structural changes of a variety of different SnO, SnO2 and GeO2 catalysts upon reduction in hydrogen were correlated with associated catalytic changes in methanol steam reforming. Studied systems include SnO, SnO2 and GeO2 thin film model catalysts prepared by vapour phase deposition and growth on polycrystalline NaCl surfaces and, for comparison, the corresponding pure oxide powder catalysts. Reduction of both the SnO2 thin film and powder at around 673 K in 1 bar hydrogen leads to a substantial reduction of the bulk structure and yields a mixture of SnO2 and metallic β-Sn. On the powder catalyst this transformation is fully reversible upon oxidation in 1 bar O2 at 673 K. Strongly reduced thin films, however, can only be re-transformed to SnO2 if the reduction temperature did not exceed 573 K. For GeO2, the situation is more complex due to its polymorphism. Whereas the tetragonal phase is structurally stable during reduction, oxidation or catalytic reaction, a small part of the hexagonal phase is always transformed into the tetragonal at 673 K independent of the gas phase used. SnO2 is highly active and CO2 selective in methanol steam reforming, but the initial high activity drops considerably upon reduction between 373 and 573 K and almost complete catalyst deactivation is observed after reduction at 673 K, which is associated with the parallel formation of β-Sn. In close correlation to the structural results, the catalytic activity and selectivity can be restored upon an oxidative catalyst regeneration at 673 K. Tetragonal GeO2 exhibits only a small activity and no pronounced selectivity to either CO or CO2, at least after reduction. In its fully oxidized state release of surface/lattice oxygen results in a non-catalytic formation of CO2 by oxidation of CO originating from catalytic dehydrogenation.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos (down) 000275580600002 Publication Date 2010-01-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0926-860X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.339 Times cited 20 Open Access
  Notes Esteem 026019 Approved Most recent IF: 4.339; 2010 IF: 3.384
  Call Number UA @ lucian @ c:irua:81741 Serial 292
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Author Peng, L.; Philippaerts, A.; Ke, X.; van Noyen, J.; de Cleppel, F.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F.
  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 (down) 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 Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B.
  Title The quasiparticle band structure of zincblende and rocksalt ZnO Type A1 Journal article
  Year 2010 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
  Volume 22 Issue 12 Pages 125505,1-125505,7
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract We present the quasiparticle band structure of ZnO in its zincblende (ZB) and rocksalt (RS) phases at the Γ point, calculated within the GW approximation. The effect of the pd hybridization on the quasiparticle corrections to the band gap is discussed. We compare three systems, ZB-ZnO which shows strong pd hybridization and has a direct band gap, RS-ZnO which is also hybridized but includes inversion symmetry and therefore has an indirect band gap, and ZB-ZnS which shows a weaker hybridization due to a change of the chemical species from oxygen to sulfur. The quasiparticle corrections are calculated with different numbers of valence electrons in the Zn pseudopotential. We find that the Zn20 + pseudopotential is essential for the adequate treatment of the exchange interaction in the self-energy. The calculated GW band gaps are 2.47 eV and 4.27 eV respectively, for the ZB and RS phases. The ZB-ZnO band gap is underestimated compared to the experimental value of 3.27 by ~ 0.8 eV. The RS-ZnO band gap compares well with the experimental value of 4.5 eV. The underestimation for ZB-ZnO is correlated with the strong pd hybridization. The GW band gap for ZnS is 3.57 eV, compared to the experimental value of 3.8 eV.
  Address
  Corporate Author Thesis
  Publisher Place of Publication London Editor
  Language Wos (down) 000275496600010 Publication Date 2010-03-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.649 Times cited 53 Open Access
  Notes Iwt; Fwo; Bof-Nio Approved Most recent IF: 2.649; 2010 IF: 2.332
  Call Number UA @ lucian @ c:irua:81531 Serial 2802
Permanent link to this record
 

 
Author Turner, S.; Tavernier, S.M.F.; Huyberechts, G.; Bals, S.; Batenburg, K.J.; Van Tendeloo, G.
  Title Assisted spray pyrolysis production and characterisation of ZnO nanoparticles with narrow size distribution Type A1 Journal article
  Year 2010 Publication Journal of nanoparticle research Abbreviated Journal J Nanopart Res
  Volume 12 Issue 2 Pages 615-622
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
  Abstract Nano-sized ZnO particles with a narrow size distribution and high crystallinity were prepared from aqueous solutions with high concentrations of Zn2+ containing salts and citric acid in a conventional spray pyrolysis setup. Structure, morphology and size of the produced material were compared to ZnO material produced by simple spray pyrolysis of zinc nitrates in the same experimental setup. Using transmission electron microscopy and electron tomography it has been shown that citric acid-assisted spray pyrolysed material is made up of micron sized secondary particles comprising a shell of lightly agglomerated, monocrystalline primary ZnO nanoparticles with sizes in the 2030 nm range, separable by a simple ultrasonic treatment step.
  Address
  Corporate Author Thesis
  Publisher Place of Publication S.l. Editor
  Language Wos (down) 000275318700025 Publication Date 2009-04-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1388-0764;1572-896X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.02 Times cited 27 Open Access
  Notes Esteem 026019 Approved Most recent IF: 2.02; 2010 IF: 3.253
  Call Number UA @ lucian @ c:irua:81771 Serial 156
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