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Author Vernimmen, J.; Meynen, V.; Herregods, S.J.F.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P.
Title New insights in the formation of combined zeolitic/mesoporous materials by using a one-pot templating synthesis Type A1 Journal article
Year 2011 Publication European journal of inorganic chemistry Abbreviated Journal Eur J Inorg Chem
Volume Issue 27 Pages 4234-4240
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract (down) Zeolitic growth is often absent or occurs in separate phases when synthetic strategies based on the combination of zeolite templates and mesopore templating agents are applied. In this work, zeolitic growth and mesopore formation have been investigated at different temperatures by applying a one-pot templating approach, based on a TS-1 zeolite synthesis whereby part of the microtemplate (tetrapropylammonium hydroxide, TPAOH) is replaced by a mesotemplate (hexadecyltrimethylammonium bromide, CTMABr). Moreover, the synthesis duration and the molar ratio of the microtemplate/mesotemplate have also been studied. The different syntheses clearly show the inherent competitive mechanism between zeolitic growth and mesopore formation. These insights have led to the conclusion that by following a one-pot templating strategy with standard, nonexotic commercial templates, i.e. CTMABr and TPAOH, it is not possible to develop a true hierarchical mesoporous zeolite, meaning a mesoporous siliceous material with highly crystalline zeolitic walls. The resultant materials are instead combined zeolitic/mesoporous composite structures with, however, highly tuneable and controllable porosity characteristics.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000296143500014 Publication Date 2011-08-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-1948; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.444 Times cited 7 Open Access
Notes Fwo Approved Most recent IF: 2.444; 2011 IF: 3.049
Call Number UA @ lucian @ c:irua:91574 Serial 2315
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Author Philippaerts, A.; Paulussen, S.; Breesch, A.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Sels, B.; Jacobs, P.
Title Unprecedented shape selectivity in hydrogenation of triacylglycerol molecules with Pt/ZSM-5 zeolite Type A1 Journal article
Year 2011 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 50 Issue 17 Pages 3947-3949
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) Well tuned: ZSM-5 with platinum nanoparticles preferably hydrogenates trans fatty acids over cis isomers in model triacylglycerols for geometric reasons. The central fatty acid chain reacts faster, pointing to pore mouth adsorption in a tuning fork conformation (see picture). This conformation induces stepwise hydrogenation, resulting in fast removal of the unstable central triene, while formation of saturated chains is limited.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000289514100025 Publication Date 2011-03-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited 31 Open Access
Notes Approved Most recent IF: 11.994; 2011 IF: 13.455
Call Number UA @ lucian @ c:irua:88381 Serial 3814
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Author Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Lebedev, O.I.; Parfenova, A.; Turner, S.; Tondello, E.; Van Tendeloo, G.
Title Tailored vapor-phase growth of CuxO-TiO2(x=1,2) nanomaterials decorated with Au particles Type A1 Journal article
Year 2011 Publication Langmuir: the ACS journal of surfaces and colloids Abbreviated Journal Langmuir
Volume 27 Issue 10 Pages 6409-6417
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) We report on the fabrication of CuxOTiO2 (x = 1, 2) nanomaterials by an unprecedented vapor-phase approach. The adopted strategy involves the growth of porous CuxO matrices by means of chemical vapor deposition (CVD), followed by the controlled dispersion of TiO2 nanoparticles. The syntheses are performed on Si(100) substrates at temperatures of 400550 °C under wet oxygen atmospheres, adopting Cu(hfa)2·TMEDA (hfa =1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine) and Ti(O-iPr)2(dpm)2 (O-iPr = isopropoxy; dpm = 2,2,6,6-tetramethyl-3,5-heptanedionate) as copper and titanium precursors, respectively. Subsequently, finely dispersed gold nanoparticles are introduced in the as-prepared systems via radio frequency (RF)-sputtering under mild conditions. The synthesis process results in the formation of systems with chemical composition and nano-organization strongly dependent on the nature of the initial CuxO matrix and on the deposited TiO2 amount. The decoration with low-size gold clusters paves the way to the engineering of hierarchically organized nanomaterials.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000290292900082 Publication Date 2011-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0743-7463;1520-5827; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.833 Times cited 36 Open Access
Notes Fwo Approved Most recent IF: 3.833; 2011 IF: 4.186
Call Number UA @ lucian @ c:irua:88940 Serial 3467
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Author Kalkert, C.; Krisponeit, J.-O.; Esseling, M.; Lebedev, O.I.; Moshnyaga, V.; Damaschke, B.; Van Tendeloo, G.; Samwer, K.
Title Resistive switching at manganite/manganite interfaces Type A1 Journal article
Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 99 Issue 13 Pages 132512-132512,3
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) We report bipolar resistive switching between the interfaces of manganite nanocolumns. La0.7Sr0.3MnO3 films were prepared on Al2O3 substrates, where the films grow in nanocolumns from the substrate to the surface. Conductive atomic force microscopy directly detects that the resistive switching is located at the boundaries of the grains. Furthermore, mesoscopic transport measurements reveal a tunnel magnetoresistance. In combination with the resistive switching, this leads to a total of four different resistive states.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000295618000052 Publication Date 2011-09-29
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 10 Open Access
Notes Approved Most recent IF: 3.411; 2011 IF: 3.844
Call Number UA @ lucian @ c:irua:91884 Serial 2881
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Author Fedina, L.; Lebedev, O.I.; Van Tendeloo, G.; van Landuyt, J.; Mironov, O.A.; Parker, E.H.C.
Title In situ HREM irradiation study of point-defect clustering in MBE-grown strained Si1-xGex/(001)Si structures Type A1 Journal article
Year 2000 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 61 Issue 15 Pages 10336-10345
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) We present a detailed analysis of the point-defect clustering in strained Si/Si(1-x)Ge(x)/(001)Si structures, including the interaction of the point defects with the strained interfaces and the sample surface during 400 kV electron irradiation at room temperature. Point-defect cluster formation is very sensitive to the type and magnitude of the strain in the Si and Si(1-x)Ge(x) layers. A small compressive strain (-0.3%) in the SiGe alloy causes an aggregation of vacancies in the form of metastable [110]-oriented chains. They are located on {113} planes and further recombine with interstitials. Tensile strain in the Si layer causes an aggregation of interstitial atoms in the forms of additional [110] rows which are inserted on {113} planes with [001]-split configurations. The chainlike configurations are characterized by a large outward lattice relaxation for interstitial rows (0.13 +/-0.01 nm) and a very small inward relaxation for vacancy chains (0.02+/-0.01 nm). A compressive strain higher than -0.5% strongly decreases point-defect generation inside the strained SiGe alloy due to the large positive value of the formation volume of a Frenkel pair. This leads to the suppression of point-defect clustering in a strained SiGe alloy so that SiGe relaxes via a diffusion of vacancies from the Si layer, giving rise to an intermixing at the Si/SiGe interface. In material with a 0.9% misfit a strongly increased flow of vacancies from the Si layer to the SiGe layer and an increased biaxial strain in SiGe bath promote the preferential aggregation of vacancies in the (001) plane, which relaxes to form intrinsic 60 degrees dislocation loops.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000086606200082 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 27 Open Access
Notes Conference Name: Microsc. Semicond. Mater. Conf. Approved Most recent IF: 3.836; 2000 IF: NA
Call Number UA @ lucian @ c:irua:103456 Serial 1577
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Author Turner, S.; Lebedev, O.I.; Schroeder, F.; Fischer, R.A.; Van Tendeloo, G.
Title Direct imaging of loaded metal-organic framework materials (metal@MOF-5) Type A1 Journal article
Year 2008 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 20 Issue 17 Pages 5622-5627
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) We illustrate the potential of advanced transmission electron microscopy for the characterization of a new class of soft porous materials: metal@Zn4O(bdc)3 (metal@MOF-5; bdc = 1,4-benzenedicarboxylate). By combining several electron microscopy techniques (transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and electron tomography) and by carefully reducing the electron dose to avoid beam damage, it is possible to simultaneously characterize the MOF-5 framework material and the loaded metal nanoparticles. We also demonstrate that electron tomography can be used to accurately determine the position and distribution of the particles within the MOF-5 framework. To demonstrate the implementation of these microscopy techniques and what kind of results can be expected, measurements on gas-phase-loaded metal−organic framework materials Ru@MOF-5 and Pd@MOF-5 are presented.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000258941400021 Publication Date 2008-08-07
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 112 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2008 IF: 5.046
Call Number UA @ lucian @ c:irua:76595 Serial 714
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Author Lebedev, O.I.; Turner, S.; Liu, S.; Cool, P.; Van Tendeloo, G.
Title New nano-architectures of mesoporous silica spheres analyzed by advanced electron microscopy Type A1 Journal article
Year 2012 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 4 Issue 5 Pages 1722-1727
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract (down) Using template-containing silica microspheres as a precursor, novel ordered mesoporous silica nanoparticles with a narrow pore size distribution and high crystallinity have been synthesized by various hydrothermal merging processes. Several architectures like chains, dumbbells, triangles, squares and flowers have been discovered. The linking mechanisms of these interacting silica spheres leading to the formation of ordered nano-structures are studied by HRTEM, HAADF-STEM and electron tomography and a plausible model is presented for several merging processes.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000300433700051 Publication Date 2011-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 5 Open Access
Notes Fwo Approved Most recent IF: 7.367; 2012 IF: 6.233
Call Number UA @ lucian @ c:irua:95038 Serial 2328
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Author Lorenz, H.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Klötzer, B.; Rameshan, C.; Pfaller, K.; Penner, S.
Title Pd-In2O3 interaction due to reduction in hydrogen: consequences for methanol steam reforming Type A1 Journal article
Year 2010 Publication Applied catalysis : A : general Abbreviated Journal Appl Catal A-Gen
Volume 374 Issue 1/2 Pages 180-188
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) Two different Pd/In2O3 samples including a thin film model catalyst with well-defined Pd particles grown on NaCl(0 0 1) supports and a powder catalyst prepared by an impregnation technique are examined by electron microscopy, X-ray diffraction and catalytic measurements in methanol steam reforming in order to correlate the formation of different oxide-supported bimetallic PdIn phases with catalytic activity and selectivity. A PdIn shell around the Pd particles is observed on the thin film catalyst after embedding the Pd particles in In2O3 at 300 K, likely because alloying to PdIn and oxidation to In2O3 are competing processes. Increased PdIn bimetallic formation is observed up to 573 K reduction temperature until at 623 K the film stability limit in hydrogen is reached. Oxidative treatments at 573 K lead to decomposition of PdIn and to the formation of an In2O3 shell covering the Pd particles, which irreversibly changes the activity and selectivity pattern to clean In2O3. PdIn and Pd2In3 phases are obtained on the powder catalyst after reduction at 573 K and 673 K, respectively. Only CO2-selective methanol steam reforming is observed in the reduction temperature range between 473 K and 573 K. After reduction at 673 K encapsulation of the bimetallic particles by crystalline In2O3 suppresses CO2 formation and only activity and selectivity of clean In2O3 are measured.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000274869900023 Publication Date 2009-12-18
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 55 Open Access
Notes Esteem 026019 Approved Most recent IF: 4.339; 2010 IF: 3.384
Call Number UA @ lucian @ c:irua:81801 Serial 3553
Permanent link to this record
 
 
Author Dluzewski, P.; Pietraszko, A.; Kozlowski, M.; Szczepanska, A.; Gorecka, J.; Baran, M.; Leonyuk, L.; Babonas, G.J.; Lebedev, O.I.; Szymczak, R.
Title Electron microscopy and X-ray structural investigations of incommensurate spin-ladder Sr4.1Ca4.7Bi0.3Cu17O29 single crystals Type A1 Journal article
Year 2000 Publication Acta physica Polonica: A: general physics, solid state physics, applied physics Abbreviated Journal Acta Phys Pol A
Volume 98 Issue 6 Pages 729-737
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) Transmission electron microscopy and X-ray diffraction proved chain/ladder incommensurate single crystal structure of investigated samples. The incommensurate ratio was determined from the X-ray and electron diffraction being equal to 0.704. Diffuse scattering intensities localised on the planes perpendicular to the c*-axis and passing through the spots originating from the periodicity of chain sublattice were detected. High-angle grain boundary or twinning formed by rotation of 33.3 degrees around [100] direction was observed. High-resolution electron microscopy images revealed the stacking faults in ac planes.
Address
Corporate Author Thesis
Publisher Place of Publication Warszawa Editor
Language Wos 000166377600007 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0587-4246 ISBN Additional Links UA library record; WoS full record;
Impact Factor 0.469 Times cited Open Access
Notes Approved Most recent IF: 0.469; 2000 IF: 0.409
Call Number UA @ lucian @ c:irua:104226 Serial 951
Permanent link to this record
 
 
Author de Witte, K.; Meynen, V.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Sepúlveda-Escribano, A.; Rodríguez-Reinoso, F.; Vansant, E.F.; Cool, P.
Title Multi-step loading of titania on mesoporous silica: influence of the morphology and the porosity on the catalytic degradation of aqueous pollutants and VOC's Type A1 Journal article
Year 2008 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ
Volume 84 Issue 1/2 Pages 125-132
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract (down) Titania nanoparticles have been deposited on inert porous silica supports with high specific surface area. These materials have potential applications in paint and textile industry as the titania particles selectively deposited on the inner surface of the silica supports act as a photocatalyst. The inert external surface is necessary to avoid photodegradation of the textile material or the paint components. The photocatalytic activity of the catalysts has been evaluated with two catalytic setups. One setup in aqueous phase, for the degradation of dyes such as rhodamine-6G, is commonly used. The second setup is a continuous flow gaseous phase setup which was used for the mineralization of ethanol as a representative volatile organic compound (VOC). The influence of the porosity and the morphology of the silica supports on the photocatalytic activity are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000260728300017 Publication Date 2008-04-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0926-3373; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.446 Times cited 24 Open Access
Notes Iwt 30916; Fwo Approved Most recent IF: 9.446; 2008 IF: 4.853
Call Number UA @ lucian @ c:irua:68279 Serial 2213
Permanent link to this record
 
 
Author Lebedev, O.I.; Verbeeck, J.; Van Tendeloo, G.; Hayashi, N.; Terashima, T.; Takano, M.
Title Structure and microstructure of epitaxial SrnFenO3n-1 films Type A1 Journal article
Year 2004 Publication Philosophical magazine Abbreviated Journal Philos Mag
Volume 84 Issue 36 Pages 3825-3841
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract (down) Thin films of SrFeO3-x (0 less than or equal to x less than or equal to 0.5) (SFO) grown on a (LaAlO3)(0.3) (SrAl0.5Ta0.5O3)(0.7) (LSAT) substrate by Pulsed laser deposition have been structurally investigated by electron diffraction and high resolution transmission electron microscopy for different post-deposition oxygen treatments. During the deposition and post-growth oxidation, the oxygen-reduced SFO films accept extra oxygen along the tetrahedral layers to minimize the elastic strain energy. The oxidation process stops at a concentration SFO2.875 and/or SFO2.75 because a zero misfit with the LSAT substrate is reached. A possible growth mechanism and phase transition mechanism are suggested. The non-oxidized films exhibit twin boundaries having a local perovskite-type structure with a nominal composition close to SFO3.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000225854700001 Publication Date 2005-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1478-6435;1478-6443; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.505 Times cited 4 Open Access
Notes reprint Approved Most recent IF: 1.505; 2004 IF: 1.167
Call Number UA @ lucian @ c:irua:54755 Serial 3287
Permanent link to this record
 
 
Author Müller, M.; Turner, S.; Lebedev, O.I.; Wang, Y.; Van Tendeloo, G.; Fischer, R.A.
Title Au@MOF-5 and Au/Mox@MOF-5 (M = Zn, Ti; x = 1, 2) : preparation and microstructural characterisation Type A1 Journal article
Year 2011 Publication European journal of inorganic chemistry Abbreviated Journal Eur J Inorg Chem
Volume Issue 12 Pages 1876-1887
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The Zn-carboxylate-based porous coordination polymer MOF-5 [Zn4O(bdc)3] and the metal oxide loaded materials ZnO@MOF-5 and TiO2@MOF-5 were loaded in a second step with the precursor [ClAuCO] to yield intermediate materials denoted as [ClAuCO]@MOF-5, [ClAuCO]/ZnO@MOF-5 and [ClAuCO]/TiO2@MOF-5. These composites were decomposed to Au@MOF-5, Au/ZnO@MOF-5 and Au/TiO2@MOF-5 under hydrogen at 100 °C. The nanoparticle-loaded hybrid materials were characterised by powder X-ray diffraction (PXRD), IR spectroscopy, X-ray photoelectron spectroscopy (XPS) and N2 sorption measurements, which reveal an intact MOF-5 structure that maintains a high specific surface area. For Au@MOF-5, crystalline Au nanoparticles were distributed over the MOF matrix in a homogeneous fashion with a size of ca. 13 nm, evidenced by high resolution transmission electron microscopy. In the case of Au/ZnO@MOF-5, the Au and metal oxide particles of a few nm in size were coexistent in a given volume of the MOF-5 matrix and were not separated in different crystalline MOF particles. For the TiO2 loaded materials the oxide is preferentially located near the outer surface of the MOF particles, leading to an increase of larger exterior Au particles in comparison to very small interior Au particles as observed for the other materials. Au@MOF-5, Au/ZnO@MOF-5 and Au/TiO2@MOF-5 were tested in liquid-phase oxidation of alcohols. Preliminary results show a high activity for the Au loaded materials in this reaction. This observation is attributed to the microstructure of the composites with very small Au particles distributed homogeneously over the MOF matrix.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000289644300004 Publication Date 2011-03-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-1948; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.444 Times cited 75 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 2.444; 2011 IF: 3.049
Call Number UA @ lucian @ c:irua:88644 Serial 205
Permanent link to this record
 
 
Author Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hebert, S.
Title Metal to insulator transition in the n-type hollandite vanadate Pb1.6V8O16 Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 3 Pages 035122, 1-035122,5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The transport and magnetic measurements of polycrystalline Pb1.6V8O16 hollandite reveal a concomitant metal to insulator and antiferromagnetic transition at TMI≈140 K. A clear localization is found below TMI, evidenced by a rapid increase in the absolute value of the negative Seebeck coefficient. The structural study by x-ray and transmission electron microscopy confirms the hollandite structure and shows that no structural transition occurs at TMI, ruling out a possible charge orbital ordering. The negative Seebeck coefficient observed from 50 K up to 900 K, with values reaching S=−38 μV K−1 at 900 K, is explained by the electron doping of ∼1.4e− in the V empty t2g orbitals responsible for the bad metal resistivity (ρ900 K∼2 mΩ cm). As this S value is close to that obtained by considering only the spin and orbital degeneracies, it is expected that |S| for such vanadates will not be sensitive at high temperature to the t2g band filling
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280366300002 Publication Date 2010-07-27
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 10 Open Access
Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84065 Serial 2009
Permanent link to this record
 
 
Author Lebedev, O.I.; Van Tendeloo, G.; Attfield, J.P.; McLaughlin, A.C.
Title Defect structure of ferromagnetic superconducting RuSr2GdCu2O8 Type A1 Journal article
Year 2006 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 73 Issue 22 Pages
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The structure and defect structure of superconducting ferromagnetic bulk RuSr2GdCu2O8 has been investigated using high-resolution transmission electron microscopy and high-resolution scanning transmission microscopy. Two distinct, but closely related structures, due to ordering of rotated RuO6 octahedra and due to Cu substitution in the Ru-O layer, have been revealed. The structure of Ru1-xSr2GdCu2+xO8-delta can be described as a periodic alteration along the c axis of CuO4 planes and RuO6 octahedra. The unit-cell parameters of this phase are root 2a(p) x root 2a(p) x 2c. The possible influence of this phase and defect structure on the sensitivity of the superconductivity and magnetic properties is discussed. Local defects such as 90 S domain boundaries, (130) antiphase boundaries, and the associated dislocations are analyzed.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000238696300115 Publication Date 2006-06-26
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 11 Open Access
Notes Iap V-I Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ c:irua:59707 Serial 619
Permanent link to this record
 
 
Author Esken, D.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Fischer, R.A.
Title Au@ZIFs: stabilization and encapsulation of cavity-size matching gold clusters inside functionalized Zeolite Imidazolate Frameworks, ZIFs Type A1 Journal article
Year 2010 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 22 Issue 23 Pages 6393-6401
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The selective formation and stabilization of very small, naked metal particles inside the cavities of metal organic frameworks (MOFs) and the simultaneous realization of an even distribution of the particles throughout the crystalline MOF host matrix over a wide range of metal loading are challenging goals. MOFs reveal high specific surface areas, tunable pore sizes, and organic linkers, which are able to interact with guests. The chemically very robust zeolite imidazolate frameworks (ZIFs) are a subclass of MOFs. We chose the microporous sodalite-like ZIF-8 (Zn(MelM)(2); IM = imidazolate) and ZIF-90 (Zn(ICA)(2); ICA = imidazolate-2-carboxyaldehyde) as host matrices to influence the dispersion of imbedded gold nanoparticles (Au NPs). The metal loading was achieved via gas phase infiltration of [Au(CO)Cl] followed by a thermal hydrogenation step to form the Au NPs. Low-dose high-resolution transmission electron microscopy ((HR)TEM) and electron tomography reveal a homogeneous distribution of Au NPs throughout the ZIF matrix. The functional groups of ZIF-90 direct the anchoring of intermediate Au species and stabilize drastically smaller and quite monodisperse Au NPs in contrast to the parent not functionalized ZIF-8. The particles can be very small, match the cavity size and approach defined molecular clusters of magic numbers, i.e., Au(55), independently from the level of loading. Post-synthetic oxidation of the aldehyde groups to yield alkyl esters by the adjacent, catalytically active metal NPs is presented as a new concept of encapsulating nanoparticles inside MOFs and allows multiple steps of metal loadings without decomposition of the MOF.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000284975100025 Publication Date 2010-11-12
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 194 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2010 IF: 6.400
Call Number UA @ lucian @ c:irua:95530 Serial 208
Permanent link to this record
 
 
Author Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Matsushita, N.; Yoshimura, M.; Guitian, F.
Title Rational synthesis of a nanocrystalline calcium phosphate cement exhibiting rapid conversion to hydroxyapatite Type A1 Journal article
Year 2009 Publication Materials science and engineering: part C: biomimetic materials Abbreviated Journal Mat Sci Eng C-Mater
Volume 29 Issue 7 Pages 2124-2132
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The rational synthesis, comprehensive characterization, and mechanical and micromechanical properties of a calcium phosphate cement are presented. Hydroxyapatite cement biomaterial was synthesized from reactive sub-micrometer-sized dicalcium phosphate dihydrate and tetracalcium phosphate via a dissolution-precipitation reaction using water as the liquid phase. As a result nanostructured, Ca-deficient and carbonated B-type hydroxyapatite is formed. The cement shows good processibility, sets in 22 ± 2 min and entirely transforms to the end product after 6 h of setting reaction, one of the highest conversion rates among previously reported for calcium phosphate cements based on dicalcium and tetracalcium phosphates. The combination of all elucidated physical-chemical traits leads to an essential bioactivity and biocompatibility of the cement, as revealed by in vitro acellular simulated body fluid and cell culture studies. The compressive strength of the produced cement biomaterial was established to be 25 ± 3 MPa. Furthermore, nanoindentation tests were performed directly on the cement to probe its local elasticity and plasticity at sub-micrometer/micrometer level. The measured elastic modulus and hardness were established to be Es = 23 ± 3.5 and H = 0.7 ± 0.2 GPa, respectively. These values are in close agreement with those reported in literature for trabecular and cortical bones, reflecting good elastic and plastic coherence between synthesized cement biomaterial and human bones.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000270159200008 Publication Date 2009-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0928-4931; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.164 Times cited 18 Open Access
Notes Esteem 026019 Approved Most recent IF: 4.164; 2009 IF: NA
Call Number UA @ lucian @ c:irua:79312 Serial 2812
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Author Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Lebedev, O.I.; Turner, S.; Sada, C.; Depero, L.E.; Van Tendeloo, G.; Barreca, D.
Title Fluorine doped Fe2O3 nanostructures by a one-pot plasma-assisted strategy Type A1 Journal article
Year 2013 Publication RSC advances Abbreviated Journal Rsc Adv
Volume 3 Issue 45 Pages 23762-23768
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The present work reports on the synthesis of fluorine doped Fe2O3 nanomaterials by a single-step plasma enhanced-chemical vapor deposition (PE-CVD) strategy. In particular, Fe(hfa)2TMEDA (hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine) was used as molecular source for both Fe and F in Ar/O2 plasmas. The structure, morphology and chemical composition of the synthesized nanosystems were thoroughly analyzed by two-dimensional X-ray diffraction (XRD2), field emission-scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS) and transmission electron microscopy (TEM). A suitable choice of processing parameters enabled the selective formation of α-Fe2O3 nanomaterials, characterized by an homogeneous F doping, even at 100 °C. Interestingly, a simultaneous control of the system nanoscale organization and fluorine content could be achieved by varying the sole growth temperature. The tailored properties of the resulting materials can be favourably exploited for several technological applications, ranging from photocatalysis, to photoelectrochemical cells and gas sensing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000326395800141 Publication Date 2013-10-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.108 Times cited 23 Open Access
Notes Fwo Approved Most recent IF: 3.108; 2013 IF: 3.708
Call Number UA @ lucian @ c:irua:111091 Serial 1237
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Author Armelao, L.; Barreca, D.; Bottaro, G.; Gasparotto, A.; Maccato, C.; Tondello, E.; Lebedev, O.I.; Turner, S.; Van Tendeloo, G.; Štangar, U.L.
Title Rational design of Ag/TiO2 nanosystems by a combined RF-sputtering/sol-gel approach Type A1 Journal article
Year 2009 Publication ChemPhysChem : a European journal of chemical physics and physical chemistry Abbreviated Journal Chemphyschem
Volume 10 Issue 18 Pages 3249-3259
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The present work is devoted to the preparation of Ag/TiO2 nanosystems by an original synthetic strategy, based on the radio-frequency (RF) sputtering of silver particles on titania-based xerogels prepared by the sol-gel (SG) route. This approach takes advantage of the synergy between the microporous xerogel structure and the infiltration power characterizing RF-sputtering, whose combination enables the obtainment of a tailored dispersion of Ag-containing particles into the titania matrix. In addition, the systems chemico-physical features can be tuned further through proper ex situ thermal treatments in air at 400 and 600 °C. The synthesized composites are extensively characterized by the joint use of complementary techniques, that is, X-ray photoelectron and X-ray excited Auger electron spectroscopies (XPS, XE-AES), secondary ion mass spectrometry (SIMS), glancing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), electron diffraction (ED), high-angle annular dark field scanning TEM (HAADF-STEM), energy-filtered TEM (EF-TEM) and optical absorption spectroscopy. Finally, the photocatalytic performances of selected samples in the decomposition of the azo-dye Plasmocorinth B are preliminarily investigated. The obtained results highlight the possibility of tailoring the system characteristics over a broad range, directly influencing their eventual functional properties.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000273410600015 Publication Date 2009-10-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1439-4235;1439-7641; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.075 Times cited 56 Open Access
Notes Esteem 026019 Approved Most recent IF: 3.075; 2009 IF: 3.453
Call Number UA @ lucian @ c:irua:80561 Serial 2811
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Author Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerol, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.N.; Park, Y.W.
Title The superconducting bismuth-based mixed oxides Type A1 Journal article
Year 2002 Publication Current applied physics T2 – QTSM and QFS 02 Symposium, MAY 08-10, 2002, SEOUL, SOUTH KOREA Abbreviated Journal Curr Appl Phys
Volume 2 Issue 5 Pages 425-430
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The present paper describes the synthesis, characterization of mixed-valence bismuthates with three- or two-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12 K exists in the narrow range (x approximate to 0.5-0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the three-dimensional octahedral framework has close to the ideal perovskite structure arrangement. The layered type (Ba,K)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated. Buckling of the (BiO2) layers in the structure of the n = 2 member occurs due to the ordering of alkaline- and alkaline-earth cations between two independent positions. The formation of the one-layer bismuthate was revealed by Electron Microscopy and XRPD studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. (C) 2002 Published by Elsevier Science B.V.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000179330900015 Publication Date 2002-11-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1567-1739; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.971 Times cited 2 Open Access
Notes Approved Most recent IF: 1.971; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103336 Serial 3598
Permanent link to this record
 
 
Author Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerof, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.; Park, Y.W.
Title The superconducting bismuth-based mixed oxides Type A1 Journal article
Year 2003 Publication Journal of low temperature physics T2 – International Conference on Physics and Chemistry of Molecular and Oxide, Superconductors (MOS2002), AUG 13-18, 2002, HSINCHU, TAIWAN Abbreviated Journal J Low Temp Phys
Volume 131 Issue 3-4 Pages 575-587
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The present paper describes the synthesis, characterization of mixed-valence bismuthates with 3- or 2-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12K exists in the narrow range (x approximate to 0.5 – 0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the 3-dimensional octahedral framework has close to the ideal perovskite structure arrangement. At the same time compositions with close to optimal Bi-valence (x = 0.33 and 0.43) do not show any sign of superconductivity, probably, due to structural distortions. The layered type (BaK)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated Buckling of the (BiO2) layers in the structure of the n = 2 member was revealed The formation of the n=1 bismuthate was found by Electron Microscopy and X-ray powder diffraction studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000181768000061 Publication Date 2003-04-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.3 Times cited 3 Open Access
Notes Approved Most recent IF: 1.3; 2003 IF: 1.171
Call Number UA @ lucian @ c:irua:102803 Serial 3597
Permanent link to this record
 
 
Author Lukashin, A.V.; Eliseev, A.A.; Zhuravleva, N.G.; Vertegel, A.A.; Tretyakov, Y.D.; Lebedev, O.I.; Van Tendeloo, G.
Title One-step synthesis of shelled PbS nanoparticles in a layered double hydroxide matrix Type A1 Journal article
Year 2004 Publication Mendeleev communications Abbreviated Journal Mendeleev Commun
Volume Issue 4 Pages 174-176
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The one-step preparation of capped PbS nanoparticles in an inorganic matrix via UV-induced decomposition of lead thiosulfate complexes intercalated into a hydrotalcite-type layered double hydroxide is reported.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000224247100025 Publication Date 2004-09-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0959-9436; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.741 Times cited 9 Open Access
Notes Approved Most recent IF: 1.741; 2004 IF: 0.640
Call Number UA @ lucian @ c:irua:103735 Serial 2468
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Author Wang, Z.-H.; Lebedev, O.I.; Van Tendeloo, G.; Cristiani, G.; Habermeier, H.-U.
Title Crosshatching on La0.5Ca0.5MnO3 ultrathin films epitaxially grown on SrTiO3(100) Type A1 Journal article
Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 77 Issue 11 Pages 1-5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The morphological evolution in La(0.5)Ca(0.5)MnO(3)/SrTiO(3)(100) ultrathin films has been revealed by atomic force microscopy. It was found that ordered linear defects, which are in 1-2 unit cells high and oriented along the cubic [110] and [100] directions, first appear on the smooth surface of films with a thickness of 10 nm. As the epitaxial growth proceeds, these lines on surface develop into a crosshatch pattern for films with a thickness of 25 nm. Using the results of transmission electron microscopy and electrical measurements, we discuss the interplay between the surface pattern formation, the internal dislocation structure, and the variations in the electrical properties.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000254542800126 Publication Date 2008-03-18
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 8 Open Access
Notes ESTEEM nr 026019 Approved Most recent IF: 3.836; 2008 IF: 3.322
Call Number UA @ lucian @ c:irua:70022 Serial 548
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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 (down) 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 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
Permanent link to this record
 
 
Author Ding, J.F.; Lebedev, O.I.; Turner, S.; Tian, Y.F.; Hu, W.J.; Seo, J.W.; Panagopoulos, C.; Prellier, W.; Van Tendeloo, G.; Wu, T.
Title Interfacial spin glass state and exchange bias in manganite bilayers with competing magnetic orders Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 87 Issue 5 Pages 054428-7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) 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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000315271200002 Publication Date 2013-02-22
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 98 Open Access
Notes FWO; COUNTATOMS; Hercules Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:107349 Serial 1696
Permanent link to this record
 
 
Author Wang, Z.-H.; Kronmüller, H.; Lebedev, O.I.; Gross, G.M.; Razavi, F.S.; Habermeier, H.U.; Shen, B.G.
Title Phase transition and magnetic anisotropy of (La,Sr)MnO3 thin films Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue 5 Pages 054411-54416
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The magnetic proper-ties and their correlation with the microstructure and electrical transport are investigated in La0.88Sr0.1MnO3 films grown on (100)SrTiO3 Single crystal substrates with thickness ranging from 100 to 2500 Angstrom. The ultrathin film (t = 100 Angstrom) has a single ferromagnetic transition (FMT) at T-c of 250 K, whereas the thicker films exhibit two FMTs, with the main one at a lowered T-c of 200 K while the minor one around 300 K. Furthermore, a thickness dependent magnetic anisotropy has been found, strongly indicating the existence of strain effect, which is also revealed by the transmission electron microscopy study. The suppressed Jahn-Teller distortion (JTD) by the epitaxial strain, and the recovered JTD due to the strain relexation are suggested to explain the metallic behavior in thin films and the insulating behavior in the thick film (t = 2500 Angstrom), repectively.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000173647000058 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 23 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103883 Serial 2592
Permanent link to this record
 
 
Author Esken, D.; Zhang, X.; Lebedev, O.I.; Schröder, F.; Fischer, R.A.
Title Pd@MOF-5: limitations of gas-phase infiltration and solution impregnation of [Zn4O(bdc)3] (MOF-5) with metalorganic palladium precursors for loading with Pd nanoparticles Type A1 Journal article
Year 2009 Publication Journal of materials chemistry Abbreviated Journal J Mater Chem
Volume 19 Issue 9 Pages 1314-1319
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The limitations of the loading of the porous metalorganic framework [Zn4O(bdc)3] (bdc = benzene-1,4-dicarboxylate; MOF-5 or IRMOF-1) with Pd nanoparticles was investigated. First, the volatile organometallic precursor [Pd(5-C5H5)(3-C3H5)] was employed to get the inclusion compound [Pd(5-C5H5)(3-C3H5)]x@MOF-5 via gas-phase infiltration at 10-3 mbar. A loading of four molecules of [Pd(5-C5H5)(3-C3H5)] per formula unit of MOF-5 (x = 4) can be reached (35 wt.% Pd). Second, the metalorganic precursor [Pd(acac)2] (acac = 2,4-pentanedionate) was used and the inclusion materials [Pd(acac)2]x@MOF-5 of different Pd loadings were obtained by incipient wetness infiltration. However, the maximum loading was lower as compared with the former case with about two precursor molecules per formula unit of MOF-5. Both loading routes are suitable for the synthesis of Pd nanoparticles inside the porous host matrix. Homogeneously distributed nanoparticles with diameter of 2.4(±0.2) nm can be achieved by photolysis of the inclusion compounds [Pd(5-C5H5)(3-C3H5)]x@MOF-5 (x 4), while the hydrogenolysis of [Pd(acac)2]x@MOF-5 (x 2) leads to a mixture of small particles inside the network (< 3 nm) and large Pd agglomerates (40 nm) on the outer surface of the MOF-5 specimens. The pure Pdx@MOF-5 materials proved to be stable under hydrogen pressure (2 bar) at 150 °C over many hours. Neither hydrogenation of the bdc linkers nor particle growth was observed. The new composite materials were characterized by 1H/13C-MAS-NMR, powder XRD, ICP-AES, FT-IR, N2 sorption measurements and high resolution TEM. Raising the Pd loading of a representative sample Pd4@MOF-5 (35 wt.% Pd) by using [Pd(5-C5H5)(3-C3H5)] as precursor in a second cycle of gas-phase infiltration and photolysis was accompanied by the collapse of the long-range crystalline order of the MOF.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000263450300015 Publication Date 2009-01-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0959-9428;1364-5501; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 100 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:76318 Serial 2565
Permanent link to this record
 
 
Author Volkova, N.E.; Lebedev, O.I.; Gavrilova, L.Y.; Turner, S.; Gauquelin, N.; Seikh, M.M.; Caignaert, V.; Cherepanov, V.A.; Raveau, B.; Van Tendeloo, G.
Title Nanoscale ordering in oxygen deficient quintuple perovskite Sm2-\epsilonBa3+\epsilonFe5O15-\delta : implication for magnetism and oxygen stoichiometry Type A1 Journal article
Year 2014 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 26 Issue 21 Pages 6303-6310
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The investigation of the system SmBaFe-O in air has allowed an oxygen deficient perovskite Sm2-epsilon Ba3+epsilon Fe5O15-delta (delta = 0.75, epsilon = 0.125) to be synthesized. In contrast to the XRPD pattern which gives a cubic symmetry (a(p) = 3.934 angstrom), the combined HREM/EELS study shows that this phase is nanoscale ordered with a quintuple tetragonal cell, a(p) X a(p) X 5(ap). The nanodomains exhibit a unique stacking sequence of the A-site cationic layers along the crystallographic c-axis, namely SmBaBa/SmBa/SmBaSm, and are chemically twinned in the three crystallographic directions. The nanoscale ordering of this perovskite explains its peculiar magnetic properties on the basis of antiferromagnetic interactions with spin blockade at the boundary between the nanodomains. The variation of electrical conductivity and oxygen content of this oxide versus temperature suggest potential SOFC applications. They may be related to the particular distribution of oxygen vacancies in the lattice and to the 3d(5)(L) under bar configuration of iron.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000344905600029 Publication Date 2014-10-07
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 16 Open Access
Notes The UrFU authors were financially supported by the Ministry of Education and Science of Russian Federation (project N 4.1039.2014/K) and by UrFU under the Framework Program of development of UrFU through the «Young scientists UrFU» competition. The CRISMAT authors gratefully acknowledge the EC, the CNRS and the French Minister of Education and Research for financial support through their Research, Strategic and Scholarship programs. This work was supported by funding from the European Research Council under the Seventh Framework Program (FP7), ERC grant N°246791 – COUNTATOMS. S.T. gratefully acknowledges the fund for scientific research Flanders for a post-doctoral fellowship and for financial support under contract number G004413N. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC starting grant number 278510 – VORTEX; ECASJO_; Approved Most recent IF: 9.466; 2014 IF: 8.354
Call Number UA @ lucian @ c:irua:122137 Serial 2269
Permanent link to this record
 
 
Author Müller, M.; Lebedev, O.I.; Fischer, R.A.
Title Gas-phase loading of [Zn4O(btb)2] (MOF-177) with organometallic CVD-precursors: inclusion compounds of the type [LnM]a@MOF-177 and the formation of Cu and Pd nanoparticles inside MOF-177 Type A1 Journal article
Year 2008 Publication Journal of materials chemistry Abbreviated Journal J Mater Chem
Volume 18 Issue 43 Pages 5274-5281
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The highly porous and desolvated (activated) coordination polymer [Zn4O(btb)2] (btb = benzene-1,3,5-tribenzoate; MOF-177) was loaded with the organometallic compounds [Cp2Fe], [Cp*2Zn], [Cu(OCHMeCH2NMe2)2], [CpCuL] (L = PMe3, CNtBu) and [CpPd(3-C3H5)] via solvent-free adsorption from the gas-phase. The inclusion compounds of the type [LnM]a@MOF-177, where [LnM] indicates the respective compound and the parameter a denotes the number of molecules per formula unit of the MOF-177, were characterised by elemental analysis, FT-IR, solid-state NMR spectroscopy and by powder X-ray diffraction (PXRD). Remarkably high effective loadings of up to 11 molecules [Cp2Fe] and 10 molecules [CpPd(3-C3H5)] per cavity were determined. The analytical data prove that the host lattice and the guest molecules interact only by weak van-der-Waals forces without any significant change of the framework or the chemical nature of the included molecules. Cu nanoparticles showing the typical surface plasmon resonance at 580 nm and Pd nanoparticles of about 2.6 nm in size were formed inside the cavities of MOF-177 by the thermally activated hydrogenolysis of the inclusion compounds [CpCuCNtBu]2@MOF-177 and by photolysis of [CpPd(3-C3H5)]10@MOF-177 in an inert atmosphere (Ar). PXRD, FT-IR and NMR studies revealed that the MOF-177 matrix remained unchanged during the decomposition process of the precursors. N2 adsorption studies of the obtained materials Cu@MOF-177 (e.g. 10.6 wt.% Cu, 2309 m2 g-1) and Pd@MOF-177 (e.g. 32.5 wt.%, 1063 m2 g-1) reveal high remaining specific surface areas (Langmuir model).
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000260487300015 Publication Date 2008-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0959-9428;1364-5501; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 65 Open Access
Notes Esteem 026019 Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:75699 Serial 1318
Permanent link to this record
 
 
Author Holden, T.; Habermeier, H.-U.; Cristiani, G.; Golnik, A.; Boris, A.; Pimenov, A.; Humlicek, J.; Lebedev, O.I.; Van Tendeloo, G.; Keimer, B.; Bernhard, C.
Title Proximity induced metal-insulator transition in YBa2Cu3O7/La2/3Ca1/3MnO3 superlattices Type A1 Journal article
Year 2004 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 69 Issue 6 Pages 064505,1-064505,7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The far-infrared dielectric response of superlattices (SL) composed of superconducting YBa2Cu3O7 (YBCO) and ferromagnetic La0.67Ca0.33MnO3 (LCMO) has been investigated by ellipsometry. A drastic decrease of the free-carrier response is observed which involves an unusually large length scale of d(crit)approximate to20 nm in YBCO and d(crit)approximate to10 nm in LCMO. A corresponding suppression of metallicity is not observed in SL's where LCMO is replaced by the paramagnetic metal LaNiO3. Our data suggest that either a long-range charge transfer from the YBCO to the LCMO layers or alternatively a strong coupling of the charge carriers to the different and competitive kind of magnetic correlations in the LCMO and YBCO layers is at the heart of the observed metal-insulator transition. The low free-carrier response observed in the far-infrared dielectric response of the magnetic superconductor RuSr2GdCu2O8 is possibly related to this effect.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000220092100066 Publication Date 2004-02-21
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 101 Open Access
Notes Approved Most recent IF: 3.836; 2004 IF: 3.075
Call Number UA @ lucian @ c:irua:54743 Serial 2734
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Author Bigiani, L.; Barreca, D.; Gasparotto, A.; Andreu, T.; Verbeeck, J.; Sada, C.; Modin, E.; Lebedev, O.I.; Morante, J.R.; Maccato, C.
Title Selective anodes for seawater splitting via functionalization of manganese oxides by a plasma-assisted process Type A1 Journal article
Year 2021 Publication Applied Catalysis B-Environmental Abbreviated Journal Appl Catal B-Environ
Volume 284 Issue Pages 119684
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract (down) The electrolysis of seawater, a significantly more abundant natural reservoir than freshwater, stands as a promising alternative for sustainable hydrogen production, provided that the competitive chloride electro-oxidation is minimized. Herein, we propose an original material combination to selectively trigger oxygen evolution from seawater at expenses of chlorine generation. The target systems, based on MnO2 or Mn2O3 decorated with Fe2O3 or Co3O4, are fabricated by plasma enhanced-chemical vapor deposition of manganese oxides, functionalization with Fe2O3 and Co3O4 by sputtering, and annealing in air/Ar to obtain Mn(IV)/Mn(III) oxides. Among the various options, MnO2 decorated with Co3O4 yields the best performances in alkaline seawater splitting, with an outstanding Tafel slope of approximate to 40 mV x dec(-1) and an overpotential of 450 mV, enabling to rule out chlorine evolution. These attractive performances, resulting from the synergistic contribution of catalytic and electronic effects, open the door to low-cost hydrogen generation from seawater under real-world conditions, paving the way to eventual large-scale applications.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000623591500008 Publication Date 2020-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0926-3373 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.446 Times cited 67 Open Access OpenAccess
Notes The authors thank Padova University (DOR 2017–2020 and P-DiSC #03BIRD2018-UNIPD OXYGENA projects), as well as the INSTM Consortium (INSTMPD004 – NETTUNO project) and AMGA Foundation (Mn4Energy project), for financial support. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from a GOA project 'Solarpaint' (University of Antwerp) and from the EU-H2020 programme (grant agreement No. 823717 – ESTEEM3). J.R.M. and T.A. acknowledge Generalitat de Catalunya for financial support through the CERCA Programme, 27 M2E (2017SGR1246) and by ERDEF-MINECO coordinated projects ENE2017-85087-C3 and ENE2016-80788-C5-5-R. Thanks are also due to Proff. Gloria Tabacchi and Ettore Fois (Department of Science and High Technology, Insubria University, Como, Italy) for valuable discussions and support. Dr. Daniele Valbusa, Dr. Gianluca Corrò, Dr. Andrea Gallo and Dr. Dileep Khrishnan are gratefully acknowledged for helpful technical assistance. Approved Most recent IF: 9.446
Call Number UA @ admin @ c:irua:176718 Serial 6733
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