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“Influence of the morphology on the magneto-transport properties of laser-ablated ultrathin La0.7Ba0.3MnO3 films”. Das A, Gordon I, Wagner P, Cannaerts M, Moshchalkov VV, Bruynseraede Y, Schuddinck W, Van Tendeloo G, Borghs G, Journal of applied physics 90, 1429 (2001). http://doi.org/10.1063/1.1380217
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.068
Times cited: 2
DOI: 10.1063/1.1380217
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“Influence of the structure on the properties of NaxEuy(MoO4)z red phosphors”. Morozov VA, Lazoryak BI, Shmurak SZ, Kiselev AP, Lebedev OI, Gauquelin N, Verbeeck J, Hadermann J, Van Tendeloo G, Chemistry of materials 26, 3238 (2014). http://doi.org/10.1021/cm500966g
Abstract: Scheelite related compounds (A',A '')(n)[(B',B '')O-4](m) with B', B '' = W and/or Mo are promising new materials for red phosphors in pc-WLEDs (phosphor-converted white-light-emitting-diode) and solid-state lasers. Cation substitution in CaMoO4 of Ca2+ by the combination of Na+ and Eu3+, with the creation of A cation vacancies, has been investigated as a factor for controlling the scheelite-type structure and the luminescent properties. Na5Eu(MoO4)(4) and NaxEu(2-x)/33+square(2-x)/3MoO4 (0.138 <= x <= 0.5) phases with a scheelite-type structure were synthesized by the solid state method; their structural characteristics were investigated using transmission electron microscopy. Contrary to powder synchrotron X-ray diffraction before, the study by electron diffraction and high resolution transmission electron microscopy in this paper revealed that Na0.286Eu0.571MoO4 has a (3 + 2)D incommensurately modulated structure and that (3 + 2)D incommensurately modulated domains are present in Na0.200Eu0.600MoO4. It also confirmed the (3 + 1)D incommensurately modulated character of Na(0.138)Eu(0.621)Mo04. The luminescent properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of these phosphors show the strongest absorption at about 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The emission spectra indicate an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+, with local minima in the intensity at Na0.286Eu0.571MoO4 and Na0.200Eu0.600MoO4 for similar to 613 nm and similar to 616 nm bands. The phosphor Na5Eu(MoO4)(4) shows the brightest red light emission among the phosphors in the Na2MoO4-Eu2/3MoO4 system and the maximum luminescence intensity of Na5Eu(MoO4)(4) (lambda(ex) = 395 nm) in the D-5(0) -> F-7(2) transition region is close to that of the commercially used red phosphor YVO4:Eu3+ (lambda(ex) = 326 nm). Electron energy loss spectroscopy measurements revealed the influence of the structure and Na/Eu cation distribution on the number and positions of bands in the UV-optical-infrared regions of the EELS spectrum.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 53
DOI: 10.1021/cm500966g
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“Influence of the synthesis parameters of TiO2-SBA-15 materials on the adsorption and photodegradation of rhodamine-6G”. de Witte K, Busuioc AM, Meynen V, Mertens M, Bilba N, Van Tendeloo G, Cool P, Vansant EF, Microporous and mesoporous materials: zeolites, clays, carbons and related materials 110, 100 (2008). http://doi.org/10.1016/j.micromeso.2007.09.035
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT)
Impact Factor: 3.615
Times cited: 54
DOI: 10.1016/j.micromeso.2007.09.035
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“Influence of the Ar/O2 ratio on the growth and biaxial alignment of yttria stabilized zirconia layers during reactive unbalanced magnetron sputtering”. Mahieu S, Ghekiere P, de Winter G, Depla D, de Gryse R, Lebedev OI, Van Tendeloo G, Thin solid films : an international journal on the science and technology of thin and thick films 484, 18 (2005). http://doi.org/10.1016/j.tsf.2005.01.021
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.879
Times cited: 23
DOI: 10.1016/j.tsf.2005.01.021
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“Infrared spectra of type laB diamonds”. Woods GS, Kiflawi I, Luyten W, Van Tendeloo G, Philosophical magazine letters 67, 405 (1993). http://doi.org/10.1080/09500839308240950
Abstract: It is shown that the infrared absorption spectra of pure type IaB diamonds, namely those that on cursory examination show only a B one-phonon component and neither A nor D, and the complete absence of a B' localized-mode platelet absorption peak, may be divided into two subgroups. The defect content of specimens of one of these subgroups has been studied before and comprises slip dislocations and voidites in random homogeneous distributions unconnected with the transformation of platelets to dislocation loops. Electron microscopy of a specimen of the other subgroup, which may be recognized by the presence of weak additional one-phonon absorption near 1100 cm-1, shows a population of dislocation loops resulting from the complete transformation of a former platelet population, plus accompanying voidites. It is suggested that the extra absorption is caused by the dislocation loops. Observation of the way in which loops and voidites are distributed suggests that voidite production and platelet transformation may not, after all, be interlinked phenomena, but parallel independent processes both promoted by the same unknown conditions.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.087
Times cited: 5
DOI: 10.1080/09500839308240950
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“Insight into the growth of multiple branched MnOOH nanorods”. Li Y, Tan H, Lebedev O, Verbeeck J, Biermans E, Van Tendeloo G, Su B-L, Crystal growth &, design 10, 2969 (2010). http://doi.org/10.1021/cg100009k
Abstract: Multiple branched manganese oxide hydroxide (MnOOH) nanorods prepared by a hydrothermal process were extensively studied by transmission electron microscopy (TEM). A model of the branch formation is proposed together with a study of the interface structure. The sword-like tip plays a crucial role for the nanorods to form different shapes. Importantly, the branching occurs at an angle of around either 57 degrees or 123 degrees. Specifically, a (111) twin plane can only be formed at the interface with a 123 degrees angle. The interfaces formed with a 57 degrees angle usually contain edge dislocations. Electron energy loss spectroscopy (EELS) demonstrates that the whole crystal has a uniform chemical composition. Interestingly, an epitaxial growth of Mn3O4 at the radial surface was also observed under electron beam irradiation; this is because of the rough purification of the products. The proposed mechanism is expected to shed light on the branched/dendrite nanostructure growth and to provide opportunities for further novel nanomaterial structure growth and design.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.055
Times cited: 41
DOI: 10.1021/cg100009k
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“Insights on growth and nanoscopic investigation of uncommon iron oxide polymorphs”. Carraro G, Maccato C, Bontempi E, Gasparotto A, Lebedev OI, Turner S, Depero LE, Van Tendeloo G, Barreca D, European journal of inorganic chemistry , 5454 (2013). http://doi.org/10.1002/ejic.201300873
Abstract: Si(100)-supported Fe2O3 nanomaterials were developed by a chemical vapor deposition (CVD) approach. The syntheses, which were performed at temperatures between 400 and 550 °C, selectively yielded the scarcely studied β- and ϵ-Fe2O3 polymorphs under O2 or O2 + H2O reaction environments, respectively. Correspondingly, the observed morphology underwent a progressive evolution from interconnected nanopyramids to vertically aligned nanorods. The present study aims to provide novel insights into Fe2O3 nano-organization by a systematic investigation of the system structure/morphology and of their interrelations with growth conditions. In particular, for the first time, the β- and ϵ-Fe2O3 preparation process has been accompanied by a thorough multitechnique investigation, which, beyond X-ray photoelectron spectroscopy (XPS) and field-emission scanning electron microscopy (FESEM), is carried out by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDXS), atomic force microscopy (AFM), high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), scanning TEM electron energy-loss spectroscopy (STEM-EELS), and high-angle annular dark-field STEM (HAADF-STEM). Remarkably, the target materials showed a high structural and compositional homogeneity throughout the whole thickness of the nanodeposit. In particular, spatially resolved EELS chemical maps through the spectrum imaging (SI) technique enabled us to gain important information on the local Fe coordination, which is of crucial importance in determining the system reactivity. The described preparation method is in fact a powerful tool to simultaneously tailor phase composition and morphology of iron(III) oxide nanomaterials, the potential applications of which include photocatalysis, magnetic devices, gas sensors, and anodes for Li-ion batteries.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.444
Times cited: 18
DOI: 10.1002/ejic.201300873
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“Interface controlled electronic variations in correlated heterostructures”. Gehrke K, Moshnyaga V, Samwer K, Lebedev OI, Verbeeck J, Kirilenko D, Van Tendeloo G, Physical review : B : condensed matter and materials physics 82, 113101 (2010). http://doi.org/10.1103/PhysRevB.82.113101
Abstract: An interface modification of (LaCa)MnO3-BaTiO3 superlattices was found to massively influence magnetic and magnetotransport properties. Moreover it determines the crystal structure of the manganite layers, changing it from orthorhombic (Pnma) for the conventional superlattice (cSL), to rhombohedral (R3̅ c) for the modified one (mSL). While the cSL shows extremely nonlinear ac transport, the mSL is an electrically homogeneous material. The observations go beyond an oversimplified picture of dead interface layers and evidence the importance of electronic correlations at perovskite interfaces.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 9
DOI: 10.1103/PhysRevB.82.113101
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“Interface-induced modulation of charge and polarization in thin film Fe3O4”. Tian H, Verbeeck J, Brück S, Paul M, Kufer D, Sing M, Claessen R, Van Tendeloo G, Advanced materials 26, 461 (2014). http://doi.org/10.1002/adma.201303329
Abstract: Charge and polarization modulations in Fe3O4 are controlled by taking advantage of interfacial strain effects. The feasibility of oxidation state control by strain modification is demonstrated and it is shown that this approach offers a stable configuration at room temperature. Direct evidence of how a local strain field changes the atomic coordination and introduces atomic displacements leading to polarization of Fe ions is presented.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 19.791
Times cited: 15
DOI: 10.1002/adma.201303329
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“Interfacial spin glass state and exchange bias in manganite bilayers with competing magnetic orders”. Ding JF, Lebedev OI, Turner S, Tian YF, Hu WJ, Seo JW, Panagopoulos C, Prellier W, Van Tendeloo G, Wu T, Physical review : B : condensed matter and materials physics 87, 054428 (2013). http://doi.org/10.1103/PhysRevB.87.054428
Abstract: The magnetic properties of manganite bilayers composed of G-type antiferromagnetic (AFM) SrMnO3 and double-exchange ferromagnetic (FM) La0.7Sr0.3MnO3 are studied. A spin-glass state is observed as a result of competing magnetic orders and spin frustration at the La0.7Sr0.3MnO3/SrMnO3 interface. The dependence of the irreversible temperature on the cooling magnetic field follows the Almeida-Thouless line. Although an ideal G-type AFM SrMnO3 is featured with a compensated spin configuration, the bilayers exhibit exchange bias below the spin glass freezing temperature, which is much lower than the Néel temperature of SMO, indicating that the exchange bias is strongly correlated with the spin glass state. The results indicate that the spin frustration that originates from the competition between the AFM super-exchange and the FM double-exchange interactions can induce a strong magnetic anisotropy at the La0.7Sr0.3MnO3/SrMnO3 interface.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 98
DOI: 10.1103/PhysRevB.87.054428
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“Interlayer structure in YBCO-coated conductors prepared by chemical solution deposition”. Molina L, Egoavil R, Turner S, Thersleff T, Verbeeck J, Holzapfel B, Eibl O, Van Tendeloo G, Superconductor science and technology 26, 075016 (2013). http://doi.org/10.1088/0953-2048/26/7/075016
Abstract: The functionality of YBa2Cu3O7−δ (YBCO)-coated conductor technology depends on the reliability and microstructural properties of a given tape or wire architecture. Particularly, the interface to the metal tape is of interest since it determines the adhesion, mechanical stability of the film and thermal contact of the film to the substrate. A trifluoroacetate (TFA)metal organic deposition (MOD) prepared YBCO film deposited on a chemical solution-derived buffer layer architecture based on CeO2/La2Zr2O7 and grown on a flexible Ni5 at.%W substrate with a {100}⟨001⟩ biaxial texture was investigated. The YBCO film had a thickness was 440 nm and a jc of 1.02 MA cm−2 was determined at 77 K and zero external field. We present a sub-nanoscale analysis of a fully processed solution-derived YBCO-coated conductor by aberration-corrected scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS). For the first time, structural and chemical analysis of the valence has been carried out on the sub-nm scale. Intermixing of Ni, La, Ce, O and Ba takes place at these interfaces and gives rise to nanometer-sized interlayers which are a by-product of the sequential annealing process. Two distinct interfacial regions were analyzed in detail: (i) the YBCO/CeO2/La2Zr2O7 region (10 nm interlayer) and (ii) the La2Zr2O7/Ni5 at.%W substrate interface region (20 nm NiO). This is of particular significance for the functionality of these YBCO-coated conductor architectures grown by chemical solution deposition.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.878
Times cited: 11
DOI: 10.1088/0953-2048/26/7/075016
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“Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7”. Tsirlin AA, Abakumov AM, Van Tendeloo G, Rosner H, Physical review : B : condensed matter and materials physics 82, 054107 (2010). http://doi.org/10.1103/PhysRevB.82.054107
Abstract: We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 13
DOI: 10.1103/PhysRevB.82.054107
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“Interplay of doping and structural modulation in superconducting Bi2Sr2-xLaxCuO6+\delta thin films”. Li ZZ, Raffy H, Bals S, Van Tendeloo G, Megtert S, Physical review : B : condensed matter and materials physics 71, 174503 (2005). http://doi.org/10.1103/PhysRevB.71.174503
Abstract: We have studied the evolution of the structural modulation in epitaxial, c-axis-oriented, Bi2Sr2-xLaCuO6+delta thin films when varying the La content x and for a given x as a function of oxygen content. A series of thin films with 0 <= x <= 0.8 has been prepared in situ by rf-magnetron sputtering and characterized by R(T) measurements, Rutherford backscattering spectroscopy, transmission electron microscopy, and x-ray diffraction techniques. The oxygen content of each individual film was varied by thermal annealing across the phase diagram. The evolution of the structural modulation has been thoroughly studied by x-ray diffraction in determining the variation of the amplitude of satellite reflections in special two axes 2 theta/theta-theta scans (reciprocal space scans). It is shown that the amplitude of the modulation along the c axis decreases strongly when x increases from 0 to 0.2. It is demonstrated that this variation is essentially governed by La content x and that changing the oxygen content by thermal treatments has a much lower influence, even becoming negligible for x > 0.2. Such study is important to understand the electronical properties of Bi2Sr2-xLaxCuO6+gamma thin films.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 11
DOI: 10.1103/PhysRevB.71.174503
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“Interpretation of electron diffraction from carbon nanotube bundles presenting precise helicity”. Colomer J-F, Henrard L, Launois P, Van Tendeloo G, Lucas AA, Lambin P, Physical review : B : condensed matter and materials physics 70, 075408 (2004). http://doi.org/10.1103/PhysRevB.70.075408
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 19
DOI: 10.1103/PhysRevB.70.075408
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“Introduction to a special issue in honour of W. Owen Saxton, David J. Smith and Dirk Van Dyck on the occasion of their 65th birthdays”. Dunin-Borkowski RE, Lichte H, Tillmann K, Van Aert S, Van Tendeloo G, Ultramicroscopy 134, 1 (2013). http://doi.org/10.1016/j.ultramic.2013.07.013
Keywords: Editorial; Electron microscopy for materials research (EMAT)
Impact Factor: 2.843
Times cited: 1
DOI: 10.1016/j.ultramic.2013.07.013
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“Investigation by electron diffraction microscopy of (RE)BaCuOS polycrystalline ceramic compounds: interpretation of unexpected superstructures and influence of secondary phases”. Cloots R, Rulmont A, Krekels T, Van Tendeloo G, Diko P, Ausloos M, Journal of crystal growth 129, 394 (1993)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.698
Times cited: 5
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“Investigation of (Bi,Pb)2212 crystals : observation of modulation-free phase”. Musolino N, Bals S, Van Tendeloo G, Clayton N, Walker E, Flukiger R, Physica: C : superconductivity 401, 270 (2004). http://doi.org/10.1016/j.physc.2003.09.052
Abstract: We report the complete disappearance of the structural modulation in heavily lead-doped Bi2-xPbxSr2CaCu2O8+delta crystals observed by transmission electron microscopy. Crystals with a nominal lead content of x = 0.8, corresponding to an effective lead content of x = 0.39, yield the non-modulated phase. The superconducting properties of this modulation-free phase (beta phase) have been studied and compared to those of undoped crystals displaying the modulated phase (alpha phase). Magnetisation measurements reveal that the irreversibility field H-irr(T) and relaxation rates are strongly improved within the beta phase. Measurements of the lower critical field, H-cl, show that the anisotropy factor, E, is considerably reduced in the modulation-free crystals. This is the signature of stronger coupling between CuO2 layers which in turn deeply influences the effectiveness of the pinning. These measurements explain the enhanced pinning properties in moderately Pb-doped crystals in which the a phase and P phase coexist. The enhanced pinning is not only due to the alpha/beta interfaces, which act as effective pinning centers: the emergence of modulation-free domains, characterized by a strongly reduced anisotropy, also significantly contribute to this effect. (C) 2003 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.404
Times cited: 9
DOI: 10.1016/j.physc.2003.09.052
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“Investigation of stacking disorder in Li2SnO3”. Tarakina NV, Denisova TA, Maksimova LG, Baklanova YV, Tyutyunnik AP, Berger IF, Zubkov VG, Van Tendeloo G, Zeitschrift für Kristallographie , 375 (2009). http://doi.org/10.1524/zksu.2009.0055
Abstract: A crystal structure investigation of the low temperature Li2SnO3 modification has been carried out. X-ray, neutron powder and electron diffraction data showed that this compound crystallizes in a monoclinic unit cell with parameters: a = 5.3033(2)Å, b = 9.1738(3)Å, c = 10.0195(2)Å, β ~ 100.042(2)º and has stacking disorder along the c-axis. Simulation of diffraction patterns with different stacking faults mainly reveal the presence of rotational stacking faults with a probability of about 40% .
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 16
DOI: 10.1524/zksu.2009.0055
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“Investigation of the morphology of the mesoporous SBA-16 and SBA-15 materials”. Stevens WJJ, Lebeau K, Mertens M, Van Tendeloo G, Cool P, Vansant EF, The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical 110, 9183 (2006). http://doi.org/10.1021/jp0548725
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT)
Impact Factor: 3.177
Times cited: 109
DOI: 10.1021/jp0548725
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“Josephson phenomenology and microstructure of YBaCuO artificial grain boundaries characterized by misalignment of the c-axes”. Tafuri F, Granozio FM, Carillo F, Lombardi F, Di Uccio US, Verbist K, Lebedev O, Van Tendeloo G, Physica: C : superconductivity 327, 63 (1999). http://doi.org/10.1016/S0921-4534(99)00372-X
Abstract: YBa(2)Cu(3)O(7-delta) (YBCO) grain boundaries characterized by a misalignment of the c-axes (45 degrees c-axis tilt or 45 degrees c-axis twist) have been obtained by employing a recently implemented biepitaxial technique. Junctions based on these grain boundaries exhibit good Josephson properties useful for applications. High values of the I(C)R(N) product and a Fraunhofer-like dependence of the critical current on the magnetic field, differently from traditional biepitaxial junctions, have been obtained. The correlation between transport properties and microstructure has been investigated by Transmission Electron Microscopy (TEM), which was also performed on previously measured junctions. The presence of atomically clean basal plane (BP) faced tilt boundaries, among other types of interfaces, has been shown. The possibility of selecting these kinds of boundaries by controlling film growth, and their possible advantages in terms of reproducibility and uniformity of the junction properties an discussed. The possibility of employing these junctions to explore the symmetry of the order parameter is also discussed. (C) 1999 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.404
Times cited: 7
DOI: 10.1016/S0921-4534(99)00372-X
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“Knitting the catalytic pattern of artificial photosynthesis to a hybrid graphene nanotexture”. Quintana M, López AM, Rapino S, Toma FM, Iurlo M, Carraro M, Sartorel A, Maccato C, Ke X, Bittencourt C, Da Ros T, Van Tendeloo G, Marcaccio M, Paolucci F, Prato M, Bonchio M;, ACS nano 7, 811 (2013). http://doi.org/10.1021/nn305313q
Abstract: The artificial leaf project calls for new materials enabling multielectron catalysis with minimal overpotential, high turnover frequency, and long-term stability. Is graphene a better material than carbon nanotubes to enhance water oxidation catalysis for energy applications? Here we show that functionalized graphene with a tailored distribution of polycationic, quaternized, ammonium pendants provides an sp(2) carbon nanoplatform to anchor a totally inorganic tetraruthenate catalyst, mimicking the oxygen evolving center of natural PSII. The resulting hybrid material displays oxygen evolution at overpotential as low as 300 mV at neutral pH with negligible loss of performance after 4 h testing. This multilayer electroactive asset enhances the turnover frequency by 1 order of magnitude with respect to the isolated catalyst, and provides a definite up-grade of the carbon nanotube material, with a similar surface functionalization. Our innovation is based on a noninvasive, synthetic protocol for graphene functionalization that goes beyond the ill-defined oxidation-reduction methods, allowing a definite control of the surface properties.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 13.942
Times cited: 69
DOI: 10.1021/nn305313q
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“Landscape roughness at an atomic scale”. Van Tendeloo G, De Meulenaere P, Schryvers D, Physica: D : nonlinear phenomena 107, 401 (1997). http://doi.org/10.1016/S0167-2789(97)00108-5
Abstract: A large number of materials have a highly degenerate ground state and therefore a complex microstructure. Because of this degenerate state, phase transitions between the different phases play an important role. High resolution techniques in electron microscopy and nano-scale chemical analysis allow to study not only the microstructure but also the interfaces down to an atomic scale. We focus particularly on the ambiguity of alloys oil approaching the phase transition. The short range order (SRO) in ''1 1/20'' type alloys and the microstructure of ''tweed'' and needle formation in martensite like alloys with composition Ni5Al3 are considered in more detail.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.514
Times cited: 2
DOI: 10.1016/S0167-2789(97)00108-5
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“Large scale synthesis of carbon nanotubes and their composite materials”. Nagy JB, Fonseca A, Pierard N, Willems I, Bister G, Pirlot C, Demortier A, Delhalle J, Mekhalif Z, Niesz K, Bossuot C, Pirard J-P, Biró, LP, Konya Z, Colomer J-F, Van Tendeloo G, Kiricsi I, (2001)
Keywords: P3 Proceeding; Electron microscopy for materials research (EMAT)
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“Large-scale synthesis of single-wall carbon nanotubes by catalytic chemical vapor deposition (CCVD) method”. Colomer JF, Stephan C, Lefrant S, Van Tendeloo G, Willems I, Konya Z, Fonseca A, Laurent C, Nagy JB, Chemical physics letters 317, 83 (2000). http://doi.org/10.1016/S0009-2614(99)01338-X
Abstract: The large-scale production of single-wall carbon nanotubes (SWNTs) is reported. Large quantities of SWNTs can be synthesised by catalytic decomposition of methane over well-dispersed metal particles supported on MgO at 1000 degrees C. The thus produced SWNTs can be separated easily from the support by a simple acidic treatment to obtain a product with high yields (70-80%) of SWNTs. Because the typical synthesis time is 10 min, 1 g of SWNTs can be synthesised per day by this method. The SWNTs are characterized by high-resolution transmission electron microscopy and by Raman spectroscopy, showing the quality and the quantity of products. (C) 2000 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.815
Times cited: 344
DOI: 10.1016/S0009-2614(99)01338-X
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“A layered iron-rich 2234-type with a mixed valence of iron: the ferrimagnetic Tl-doped Fe2(Sr2-\varepsilonTl\varepsilon)Sr3Fe4O14.65”. Lepoittevin C, Malo S, Nguyen N, Hebert S, Van Tendeloo G, Hervieu M, Chemistry of materials 20, 6468 (2008). http://doi.org/10.1021/cm8014385
Abstract: A new Tl-doped strontium ferrite Fe2(Sr2-Tl)Sr3Fe4O14.65, with an original structure, has been synthesized and structurally characterized by powder X-ray diffraction and transmission electron microscopy. The TGA and Mssbauer studies evidence a mixed valence of iron. The structure exhibits a commensurate modulation, with a F-type subcell a ≈ b ≈ 5.4 Å (≈ ap√2), c ≈ 42 Å with a modulation vector q = αa* with α = 0.4. The supercell parameters have been refined as a= 27.1101(8) Å, b= 5.5187(2) Å and c= 42.0513(9) Å, in the space group Fmmm. The electron diffraction and electron microscopy data of this novel ferrite show that it can be described as a FeTl-2234-type structure corresponding to the intergrowth of a quadruple perovskite slice [(SrFeO2.8)4], with a complex rock salt related slice [Fe2(Sr2-Tl)O3.4]∞, built up of one double iron layer [Fe2O2.4] sandwiched between two [SrO] layers. The HRTEM images show that the oxygen atoms and vacancies are randomly distributed in the perovskite layers while the HAADF STEM images evidence the absence of Tl segregation in the matrix. Fe2(Sr2-Tl)Sr3Fe4O14.65 exhibits a very large value of χ (11emu/mol) at 5 K, which remains large at 400 K; the M(H) loop presents a shape characteristic of ferrimagnetism, with a large coercive field of 0.3 T. The value of magnetization saturates at 400 K at 0.68 μB/Fe. At 10 K, the value of magnetization reaches a maximum of 2 μB/Fe. The resistivity presents a semiconducting-like behavior, with ρ 800 Ω·cm at 300 K.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 8
DOI: 10.1021/cm8014385
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“The layered manganate Sr4-xBaxMn3O10: synthesis, structural and magnetic properties”. Floros N, Hervieu M, Van Tendeloo G, Michel C, Maignan A, Raveau B, Solid state sciences 2, 1 (2000). http://doi.org/10.1016/S1293-2558(00)00115-1
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.811
Times cited: 29
DOI: 10.1016/S1293-2558(00)00115-1
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“Layered ordering of vacancies of lead iron phosphate Pb3Fe2(PO4)4”. Malakho AP, Morozov VA, Pokholok KV, Lazoryak BI, Van Tendeloo G, Solid state sciences 7, 397 (2005). http://doi.org/10.1016/j.solidstatesciences.2005.01.007
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.811
Times cited: 7
DOI: 10.1016/j.solidstatesciences.2005.01.007
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“Layered perovskite-like Pb2Fe2O5 structure as a parent matrix for the nucleation and growth of crystallographic shear planes”. Batuk D, Hadermann J, Abakumov A, Vranken T, Hardy A, van Bael M, Van Tendeloo G, Inorganic chemistry 50, 4978 (2011). http://doi.org/10.1021/ic200211x
Abstract: The Pb2Fe2O5 compound with a layered intergrowth structure has been prepared by a solid-state reaction at 700 °C. The incommensurate compound crystallizes in a tetragonal system with a = 3.9037(2) Å, c = 3.9996(4) Å, and q = 0.1186(4)c*, or when treated as a commensurate approximant, a = 3.9047(2) Å, c = 36.000(3) Å, space group I4/mmm. The crystal structure of Pb2Fe2O5 was resolved from transmission electron microscopy data. Atomic coordinates and occupancies of the cation positions were estimated from high-angle annular dark-field scanning transmission electron microscopy data. Direct visualization of the positions of the oxygen atoms was possible using annular bright-field scanning transmission electron microscopy. The structure can be represented as an intergrowth of perovskite blocks and partially disordered blocks with a structure similar to that of the Bi2O2 blocks in Aurivillius-type phases. The A-cation positions at the border of the perovskite block and the cation positions in the Aurivillius-type blocks are jointly occupied by Pb2+ and Fe3+ cations, resulting in a layer sequence along the c axis: PbOFeO2PbOFeO2Pb7/8Fe1/8O1xFe5/8Pb3/8O2Fe5/8Pb3/8. Upon heating, the layered Pb2Fe2O5 structure transforms into an anion-deficient perovskite modulated by periodically spaced crystallographic shear (CS) planes. Considering the layered Pb2Fe2O5 structure as a parent matrix for the nucleation and growth of CS planes allows an explanation of the specific microstructure observed for the CS structures in the PbFeO system.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.857
Times cited: 16
DOI: 10.1021/ic200211x
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“Layered structures accomodating stoichiometry in M2X2O7 systems, as seen by diffraction and HREM”. Nihoul G, Leroux C, Cesari C, Van Tendeloo G, Electron microscopy: vol. 2 , 295 (1998)
Keywords: A3 Journal article; Electron microscopy for materials research (EMAT)
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“Lead-mercury based superconductors: the 1212 cuprate Pb0.7Hg0.3Sr2+xCa0.7Nd0.3-xCu2O7-\delta and the new oxycarbonate Pb0.7Hg0.3Sr4Cu2CO3O7”. Martin C, Hervieu M, Huvé, M, Michel C, Maignan A, Van Tendeloo G, Raveau B, Physica C-Superconductivity And Its Applications 222, 19 (1994)
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 0.942
Times cited: 49
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