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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	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	Müller, M.; Turner, S.; Lebedev, O.I.; Wang, Y.; Van Tendeloo, G.; Fischer, R.A.
Title	Au@MOF-5 and Au/Mo_x@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	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
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Author	Vernimmen, J.; Guidotti, M.; Silvestre-Albero, J.; Jardim, E.O.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Psaro, R.; Rodríguez-Reinoso, F.; Meynen, V.; Cool, P.
Title	Immersion calorimetry as a tool to evaluate the catalytic performance of titanosilicate materials in the epoxidation of cyclohexene			Type	A1 Journal article
Year	2011	Publication	Langmuir: the ACS journal of surfaces and colloids	Abbreviated Journal	Langmuir
Volume	27	Issue	7	Pages	3618-3625
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract	Different types of titanosilicates are synthesized, structurally characterized, and subsequently catalytically tested in the liquid-phase epoxidation of cyclohexene. The performance of three types of combined zeolitic/mesoporous materials is compared with that of widely studied Ti-grafted-MCM-41 molecular sieve and the TS-1 microporous titanosilicate. The catalytic test results are correlated with the structural characteristics of the different catalysts. Moreover, for the first time, immersion calorimetry with the same substrate molecule as in the catalytic test reaction is applied as an extra means to interpret the catalytic results. A good correlation between catalytic performance and immersion calorimetry results is found. This work points out that the combination of catalytic testing and immersion calorimetry can lead to important insights into the influence of the materials structural characteristics on catalysis. Moreover, the potential of using immersion calorimetry as a screening tool for catalysts in epoxidation reactions is shown.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Washington, D.C.	Editor
Language		Wos	000288970900054	Publication Date	2011-02-23
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	19	Open Access
Notes				Approved	Most recent IF: 3.833; 2011 IF: 4.186
Call Number	UA @ lucian @ c:irua:88366			Serial	1557
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Author	Lebedev, O.I.; Caignaert, V.; Raveau, B.; Pop, N.; Gozzo, F.; Van Tendeloo, G.; Pralong, V.
Title	HRTEM and neutron diffraction study of Li_xMo₅O₁₇ : from the ribbon (x=5) structure to the rock salt (x=12) structure			Type	A1 Journal article
Year	2011	Publication	Journal of solid state chemistry	Abbreviated Journal	J Solid State Chem
Volume	184	Issue	4	Pages	790-796
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Structure determination of the fully intercalated phase Li12Mo5O17 and of the deintercalated oxide Li5Mo5O17 has been carried out by electron microscopy and neutron powder diffraction. The reversible topotactic transformation between the ordered rock salt structure of the former and the ribbon structure of the latter (closely related to that of Li4Mo5O17) is explained on the following basis: both structures can be described as strips built up as an assembly of infinite ribbons of MoO6 octahedra that are five octahedra thick, and that differ by slight displacements of the octahedral ribbons. We show that the electrochemical behavior of the LixMo5O17 system is based on two sorts of Li+ sites; those that are located within the strips between the ribbons, and those that are located at the border of the strips. The high rate of Li intercalation in this oxide and its reversibility are discussed in terms of its peculiar structure.
Address
Corporate Author				Thesis
Publisher		Place of Publication	London	Editor
Language		Wos	000289597100010	Publication Date	2011-02-12
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0022-4596;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	2.299	Times cited	1	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 2.299; 2011 IF: 2.159
Call Number	UA @ lucian @ c:irua:88646			Serial	1515
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Author	Gélard, J.; Jehanathan, N.; Roussel, H.; Gariglio, S.; Lebedev, O.I.; Van Tendeloo, G.; Dubourdieu, C.
Title	Off-stoichiometry effects on the crystalline and defect structure of hexagonal manganite REMnO₃ films (RE = Y, Er, Dy)			Type	A1 Journal article
Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
Volume	23	Issue	5	Pages	1232-1238
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	The crystalline and defect structure of epitaxial hexagonal RExMnyO3 (RE = Er, Dy) films with varying cationic composition was investigated by X-ray diffraction and transmission electron microscopy. The films are composed of a strained layer at the interface with the substrate and of a relaxed layer on top of it. The critical thickness is of 10 to 25 nm. For Mn-rich films (or RE deficient), an off-stoichiometric composition maintaining the hexagonal LuMnO3-type structure is stabilized over a large range of the RE/Mn ratio (0.72−1.00), with no Mn-rich secondary phases observed. A linear dependence of the out-of-plane lattice parameter with RE/Mn is observed in this range. Out-of-phase boundary (OPB) extended defects are observed in all films and exhibit a local change in stoichiometry. Such a large solubility limit in the RE deficient region points toward the formation of vacancies on the RE site (RExMnO3−δ, with 0.72 ≤ x < 1), a phenomenon that is encountered in perovskite manganites such as LaxMnO3−δ (x < 1) and that may strongly impact the physical properties of hexagonal manganites.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Washington, D.C.	Editor
Language		Wos	000287767200022	Publication Date	2011-02-03
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	17	Open Access
Notes				Approved	Most recent IF: 9.466; 2011 IF: 7.286
Call Number	UA @ lucian @ c:irua:88649			Serial	2430
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Author	Lin, K.; Lebedev, O.I.; Van Tendeloo, G.; Jacobs, P.A.; Pescarmona, P.P.
Title	Titanosilicate beads with hierarchical porosity : synthesis and application as epoxidation catalysts			Type	A1 Journal article
Year	2011	Publication	Chemistry: a European journal	Abbreviated Journal	Chem-Eur J
Volume	16	Issue	45	Pages	13509-13518
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Porous titanosilicate beads with a diameter of 0.51.5 mm (TiSil-HPB-60) were synthesized from a preformed titanosilicate solution with a porous anion-exchange resin as template. The bead format of this material enables its straightforward separation from the reaction mixture in its application as a liquid-phase heterogeneous catalyst. The material displays hierarchical porosity (micro/mesopores) and incipient TS-1 structure building units. The titanium species are predominantly located in tetrahedral framework positions. TiSil-HPB-60 is a highly active catalyst for the epoxidation of cyclohexene with t-butyl hydroperoxide (TBHP) and aqueous H2O2. With both oxidants, TiSil-HPB-60 gave higher epoxide yields than Ti-MCM-41 and TS-1. The improved catalytic performance of TiSil-HPB-60 is mainly ascribed to the large mesopores favoring the diffusion of reagents and products to and from the titanium active sites. The epoxide yield and selectivity could be further improved by silylation of the titanosilicate beads. Importantly, TiSil-HPB-60 is a stable catalyst immune to titanium leaching, and can be easily recovered and reused in successive catalytic cycles without significant loss of activity. Moreover, TiSil-HPB-60 is active and selective in the epoxidation of a wide range of bulky alkenes.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Weinheim	Editor
Language		Wos	000285398400029	Publication Date	2010-10-07
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0947-6539;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	5.317	Times cited	38	Open Access
Notes	Iap; Goa			Approved	Most recent IF: 5.317; 2011 IF: 5.925
Call Number	UA @ lucian @ c:irua:88153			Serial	3668
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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	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
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Author	Tan, H.; Lebedev, O.I.; McLaughlin, A.C.; Van Tendeloo, G.
Title	The superstructure and superconductivity of Ru1222 based RuSr₂Gd_2-x-yY_yCe_xCu₂O_10-\delta compounds			Type	A1 Journal article
Year	2010	Publication	Superconductor science and technology	Abbreviated Journal	Supercond Sci Tech
Volume	23	Issue	11	Pages	115013-115013,8
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	For the first time, the local structure and physical properties of Ru1222 based compounds (RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta) and RuSr(2)Gd(1.8-x)Y(0.2)CexCu(2)O(10) (x = 0.90-0.55)) have been investigated and analyzed together on the very same compounds. The Ru1222 superstructure was confirmed by TEM at a local scale and was suggested to have an orthorhombic symmetry with space group Aba2 and lattice parameters a(s) similar or equal to root 2a, b(s) similar or equal to root 2a and c(s) = c. This new Ru1222 superstructure distortion from tetragonal symmetry is proposed to have a positive correlation with the superconductivity variation of these compounds. The more the distortion towards orthorhombic symmetry, the higher the critical superconducting temperature these compounds can achieve. The T(c)(0) of RuSr(2)Gd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-delta) (x = 0.85-0.55) increases monotonically from 4 to 16 K when x decreases from 0.85 to 0.70, then RuSr(2)Gd(2)Cu(2)O(8) defects emerge and the T(c) decreases with decreasing x. Ru1212 defects are observed to intergrow epitaxially with the Ru1222 structure as lamellas along the c-axis in RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta). Although Ru1212 is a superconductor, the intergrowth severely restrains its superconductivity.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Bristol	Editor
Language		Wos	000284308000013	Publication Date	2010-10-09
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0953-2048;1361-6668;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	2.878	Times cited	1	Open Access
Notes	Fwo; Esteem 026019			Approved	Most recent IF: 2.878; 2010 IF: 2.402
Call Number	UA @ lucian @ c:irua:95553			Serial	3385
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Author	Gehrke, K.; Moshnyaga, V.; Samwer, K.; Lebedev, O.I.; Verbeeck, J.; Kirilenko, D.; Van Tendeloo, G.
Title	Interface controlled electronic variations in correlated heterostructures			Type	A1 Journal article
Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
Volume	82	Issue	11	Pages	113101,1-113101,4
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
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.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Wos	000281643200001	Publication Date	2010-09-07
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	9	Open Access
Notes	This work was supported by DFG via SFB 602, TPA2.			Approved	Most recent IF: 3.836; 2010 IF: 3.774
Call Number	UA @ lucian @ c:irua:84249UA @ admin @ c:irua:84249			Serial	1691
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Author	Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hebert, S.
Title	Metal to insulator transition in the n-type hollandite vanadate Pb_1.6V₈O₁₆			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	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
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Author	Bekermann, D.; Gasparotto, A.; Barreca, D.; Devi, A.; Fischer, R.A.; Kete, M.; Štangar, U.L.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G.
Title	ZnO nanorod arrays by plasma-enhanced CVD for light-activated functional applications			Type	A1 Journal article
Year	2010	Publication	ChemPhysChem : a European journal of chemical physics and physical chemistry	Abbreviated Journal	Chemphyschem
Volume	11	Issue	11	Pages	2337-2340
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Switch of the surface properties: Supported ZnO nanorod arrays with tailored roughness and aspect ratios are successfully synthesized by plasma-enhanced chemical vapor deposition. Such nanostructures exhibit significant superhydrophilic and photocatalytic properties tunable as a function of their morphological organization (see picture). This renders them promising building blocks for the fabrication of stimuli-responsive materials.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Weinheim	Editor
Language		Wos	000281061500008	Publication Date	2010-06-16
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	38	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 3.075; 2010 IF: 3.340
Call Number	UA @ lucian @ c:irua:84594			Serial	3935
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Author	Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hébert, S.
Title	Negative magnetoresistance in a V³⁺/V⁴⁺ mixed valent vanadate			Type	A1 Journal article
Year	2010	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
Volume	96	Issue	23	Pages	232502,1-232502,3
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	The magnetotransport and magnetic properties of the PbV6O11 vanadate, crystallizing in the P63mc space group, reveal the existence of a negative magnetoresistance related to its ferromagnetic state (TC ∼ 90 K). The maximum effect is observed at 20 K reaching −30% in 9 T. The structural study of this ceramic reveals a V/Pb ratio smaller than expected from the formula. This is explained by the presence of numerous stacking faults observed by high resolution transmission electron microscopy. The existence of these planar defects acting as resistive barriers along the c axis could be responsible for tunneling magnetoresistance.
Address
Corporate Author				Thesis
Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
Language		Wos	000278695900045	Publication Date	2010-06-08
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	3.411	Times cited		Open Access
Notes				Approved	Most recent IF: 3.411; 2010 IF: 3.841
Call Number	UA @ lucian @ c:irua:83293			Serial	2291
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Author	Lorenz, H.; Zhao, Q.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Kloetzer, B.; Rameshan, C.; Pfaller, K.
Title	Origin of different deactivation of Pd/SnO₂ and Pd/GeO₂ catalysts in methanol dehydrogenation and reforming: a comparative study			Type	A1 Journal article
Year	2010	Publication	Applied catalysis : A : general	Abbreviated Journal	Appl Catal A-Gen
Volume	381	Issue	1/2	Pages	242-252
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Pd particles supported on SnO2 and GeO2 have been structurally investigated by X-ray diffraction, (High-Resolution) transmission and scanning electron microscopy after different reductive treatments to monitor the eventual formation of bimetallic phases and catalytically tested in methanol dehydrogenation/ reforming. For both oxides this included a thin film sample with well-defined Pd particles and a powder catalyst prepared by incipient wetness impregnation. The hexagonal and the tetragonal polymorph were studied for powder GeO2. Pd2Ge formation was observed on all GeO2-supported catalysts, strongly depending on the specific sample used. Reduction of the thin film at 573K resulted in full transformation into the bimetallic state. The partial solubility of hexagonal GeO2 in water and its thermal structural instability yielded Pd2Ge formation at 473 K, at the cost of a structurally inhomogeneous support and Ge metal formation at higher reduction temperatures. Pd on tetragonal GeO2 entered a state of strong metalsupport interaction after reduction at 573673 K, resulting in coalescing Pd2Ge particles on a sintered and re-crystallized support, apparently partially covering the bimetallic particles and decreasing the catalytic activity. Pd2Ge on amorphous thin film and hexagonal GeO2 converted methanol primarily via dehydrogenation to CO and H2. At 573 K, formation of Pd2Sn and also PdSn occurred on the Pd/SnO2 thin film. Pd3Sn2 (and to some extent Pd2Sn) were predominantly obtained on the respective powder catalyst. Strong deactivation with increasing reduction temperature was observed, likely not based on the classical strong metalsupport interaction effect, but rather on a combination of missing active structural ensembles on Sn-enriched bimetallic phases and the formation of metallic -Sn. Correlations to Pd and its bimetallics supported on ZnO, Ga2O3 and In2O3 were also discussed.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Amsterdam	Editor
Language		Wos	000279100700029	Publication Date	2010-04-26
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	14	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 4.339; 2010 IF: 3.384
Call Number	UA @ lucian @ c:irua:83927			Serial	2522
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Author	Lorenz, H.; Zhao, Q.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Klötzer, B.; Rameshan, C.; Penner, S.
Title	Preparation and structural characterization of SnO₂ and GeO₂ methanol steam reforming thin film model catalysts by (HR)TEM			Type	A1 Journal article
Year	2010	Publication	Materials chemistry and physics	Abbreviated Journal	Mater Chem Phys
Volume	122	Issue	2/3	Pages	623-629
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Structure, morphology and composition of different tin oxide and germanium oxide thin film catalysts for the methanol steam reforming (MSR) reaction have been studied by a combination of (high-resolution) transmission electron microscopy, selected area electron diffraction, dark-field imaging and electron energy-loss spectroscopy. Deposition of the thin films on NaCl(0 0 1) cleavage faces has been carried out by thermal evaporation of the respective SnO2 and GeO2 powders in varying oxygen partial pressures and at different substrate temperatures. Preparation of tin oxide films in high oxygen pressures (10−1 Pa) exclusively resulted in SnO phases, at and above 473 K substrate temperature epitaxial growth of SnO on NaCl(0 0 1) leads to well-ordered films. For lower oxygen partial pressures (10−3 to 10−2 Pa), mixtures of SnO and β-Sn are obtained. Well-ordered SnO2 films, as verified by electron diffraction patterns and energy-loss spectra, are only obtained after post-oxidation of SnO films at temperatures T ≥ 673 K in 105 Pa O2. Preparation of GeOx films inevitably results in amorphous films with a composition close to GeO2, which cannot be crystallized by annealing treatments in oxygen or hydrogen at temperatures comparable to SnO/SnO2. Similarities and differences to neighbouring oxides relevant for selective MSR in the third group of the periodic system (In2O3 and Ga2O3) are also discussed with the aim of cross-correlation in formation of nanomaterials, and ultimately, also catalytic properties.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Lausanne	Editor
Language		Wos	000278637900054	Publication Date	2010-04-18
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0254-0584;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	2.084	Times cited	15	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 2.084; 2010 IF: 2.356
Call Number	UA @ lucian @ c:irua:83099			Serial	2699
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Author	Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G.
Title	Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process			Type	A1 Journal article
Year	2010	Publication	Crystal growth & design	Abbreviated Journal	Cryst Growth Des
Volume	10	Issue	4	Pages	2011-2018
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Wos	000276234500080	Publication Date	2010-03-18
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1528-7483;1528-7505;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	4.055	Times cited	75	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 4.055; 2010 IF: 4.390
Call Number	UA @ lucian @ c:irua:82311			Serial	1472
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Author	Barreca, D.; Gasparotto, A.; Lebedev, O.I.; Maccato, C.; Pozza, A.; Tondello, E.; Turner, S.; Van Tendeloo, G.
Title	Controlled vapor-phase synthesis of cobalt oxide nanomaterials with tuned composition and spatial organization			Type	A1 Journal article
Year	2010	Publication	CrystEngComm	Abbreviated Journal	Crystengcomm
Volume	12	Issue	7	Pages	2185-2197
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Wos	000279627700040	Publication Date	2010-03-10
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1466-8033;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	3.474	Times cited	85	Open Access
Notes				Approved	Most recent IF: 3.474; 2010 IF: 4.006
Call Number	UA @ lucian @ c:irua:83686			Serial	503
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Author	Xu, T.; Nys, J.-P.; Addad, A.; Lebedev, O.I.; Urbieta, A.; Salhi, B.; Berthe, M.; Grandidier, B.; Stievenard, D.
Title	Faceted sidewalls of silicon nanowires: Au-induced structural reconstructions and electronic properties			Type	A1 Journal article
Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
Volume	81	Issue	11	Pages	115403,1-115403,10
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Si nanowires with a ⟨111⟩ orientation, synthesized by vapor-liquid-solid process with low silane partial pressure reactant and gold as the catalyst, are known to exhibit sawtooth facets containing gold adsorbates. We report herein the study of the nanowire morphology by means of transmission electron microscopy and scanning tunneling microscopy. The nanowires consist of faceted sidewalls. The number of the sidewalls changes from 12 to 6 along the growth axis, giving rise to nanowires with an irregular hexagonal cross section at their base. The sidewalls are covered with Au-rich clusters. Their facets also exhibit atomic structures that reveal the presence of gold, resulting from the diffusion of gold during the growth. Based on these observations, the tapering of the nanowire is found to be related to two contributions: the reduction in the catalyst particle size during the growth and lateral overgrowth from the direct incorporation of Si species onto the nanowire sidewalls. Because the rearrangement of atoms at surfaces and interfaces might affect the growth kinetics, the trigonal symmetry as well as the higher lateral growth rate on the widest sidewalls are explained from the existence of an interfacial atomic structure with two inequivalent parts in the unit cell. Finally, spectroscopic measurements were performed on the major facets and revealed a metallic behavior at 77 K.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Wos	000276248800116	Publication Date	2010-03-03
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	3.836	Times cited	42	Open Access
Notes				Approved	Most recent IF: 3.836; 2010 IF: 3.774
Call Number	UA @ lucian @ c:irua:82273			Serial	1168
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Author	Philippaerts, A.; Paulussen, S.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Poelman, H.; Bulut, M.; de Clippel, F.; Smeets, P.; Sels, B.; Jacobs, P.
Title	Selectivity in sorption and hydrogenation of methyl oleate and elaidate on MFI zeolites			Type	A1 Journal article
Year	2010	Publication	Journal of catalysis	Abbreviated Journal	J Catal
Volume	270	Issue	1	Pages	172-184
Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract	Different zeolites were tested for selective removal of methyl elaidate (trans isomer) from an equimolar mixture with methyl oleate (cis isomer). Sorption experiments of the geometric isomers show that only ZSM-5 samples with reduced Al content in the framework are able to discriminate among the bent cis and the linear trans fatty acid methyl esters. Hydrogenation experiments of equimolar methyl oleate and elaidate mixtures at low temperature (65 °C) and high hydrogen pressure (6.0 MPa), using Pt catalysts, confirm this result. Only with a Pt/NaZSM-5 catalyst outspoken selectivity for the hydrogenation of the trans isomer is obtained. In order to prepare a selective Pt/ZSM-5 catalyst, the influence of Pt addition (impregnation, ion-exchange and competitive ion-exchange) and Pt activation (different calcination and reduction temperatures) on the Pt-distribution and Pt particle size was investigated using SEM, bright-field and HR TEM, EDX, electron tomography, CO-chemisorption, XPS, XRD, and UVvis measurements. The best result in terms of hydrogenation activity and selectivity is obtained with a Pt/ZSM-5 catalyst, which is prepared via competitive ion-exchange, followed by slow calcination up to 350 °C under high O2 flow and a reduction up to 500 °C under H2. This preparation method leads to a Pt/ZSM-5 catalyst with the best Pt distribution and the smallest Pt clusters occluded in the zeolite structure. Finally, the influence of zeolite crystal size, morphology, and elemental composition of ZSM-5 on hydrogenation activity and selectivity was investigated in detail.
Address
Corporate Author				Thesis
Publisher		Place of Publication	San Diego, Calif.	Editor
Language		Wos	000275966100021	Publication Date	2010-01-28
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0021-9517;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	6.844	Times cited	24	Open Access
Notes	FWO; IAP-IV; Methusalem			Approved	Most recent IF: 6.844; 2010 IF: 5.415
Call Number	UA @ lucian @ c:irua:82435			Serial	2970
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Author	Vlasov, I.I.; Shenderova, O.; Turner, S.; Lebedev, O.I.; Basov, A.A.; Sildos, I.; Rähn, M.; Shiryaev, A.A.; Van Tendeloo, G.
Title	Nitrogen and luminescent nitrogen-vacancy defects in detonation nanodiamond			Type	A1 Journal article
Year	2010	Publication	Small	Abbreviated Journal	Small
Volume	6	Issue	5	Pages	687-694
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	An efficient method to investigate the microstructure and spatial distribution of nitrogen and nitrogen-vacancy (N-V) defects in detonation nanodiamond (DND) with primary particle sizes ranging from approximately 3 to 50 nm is presented. Detailed analysis reveals atomic nitrogen concentrations as high as 3 at% in 50% of diamond primary particles with sizes smaller than 6 nm. A non-uniform distribution of nitrogen within larger primary DND particles is also presented, indicating a preference for location within the defective central part or at twin boundaries. A photoluminescence (PL) spectrum with well-pronounced zero-phonon lines related to the N-V centers is demonstrated for the first time for electron-irradiated and annealed DND particles at continuous laser excitation. Combined Raman and PL analysis of DND crystallites dispersed on a Si substrate leads to the conclusion that the observed N-V luminescence originates from primary particles with sizes exceeding 30 nm. These findings demonstrate that by manipulation of the size/nitrogen content in DND there are prospects for mass production of nanodiamond photoemitters based on bright and stable luminescence from nitrogen-related defects.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Weinheim	Editor
Language		Wos	000275972400013	Publication Date	2010-01-27
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1613-6810;1613-6829;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	8.643	Times cited	84	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 8.643; 2010 IF: 7.336
Call Number	UA @ lucian @ c:irua:82364			Serial	2341
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Author	Zhao, Q.; Lorenz, H.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Rameshan, C.; Klötzer, B.; Konzett, J.; Penner, S.
Title	Catalytic characterization of pure SnO₂ and GeO₂ in methanol steam reforming			Type	A1 Journal article
Year	2010	Publication	Applied catalysis : A : general	Abbreviated Journal	Appl Catal A-Gen
Volume	375	Issue	2	Pages	188-195
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Structural changes of a variety of different SnO, SnO2 and GeO2 catalysts upon reduction in hydrogen were correlated with associated catalytic changes in methanol steam reforming. Studied systems include SnO, SnO2 and GeO2 thin film model catalysts prepared by vapour phase deposition and growth on polycrystalline NaCl surfaces and, for comparison, the corresponding pure oxide powder catalysts. Reduction of both the SnO2 thin film and powder at around 673 K in 1 bar hydrogen leads to a substantial reduction of the bulk structure and yields a mixture of SnO2 and metallic β-Sn. On the powder catalyst this transformation is fully reversible upon oxidation in 1 bar O2 at 673 K. Strongly reduced thin films, however, can only be re-transformed to SnO2 if the reduction temperature did not exceed 573 K. For GeO2, the situation is more complex due to its polymorphism. Whereas the tetragonal phase is structurally stable during reduction, oxidation or catalytic reaction, a small part of the hexagonal phase is always transformed into the tetragonal at 673 K independent of the gas phase used. SnO2 is highly active and CO2 selective in methanol steam reforming, but the initial high activity drops considerably upon reduction between 373 and 573 K and almost complete catalyst deactivation is observed after reduction at 673 K, which is associated with the parallel formation of β-Sn. In close correlation to the structural results, the catalytic activity and selectivity can be restored upon an oxidative catalyst regeneration at 673 K. Tetragonal GeO2 exhibits only a small activity and no pronounced selectivity to either CO or CO2, at least after reduction. In its fully oxidized state release of surface/lattice oxygen results in a non-catalytic formation of CO2 by oxidation of CO originating from catalytic dehydrogenation.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Amsterdam	Editor
Language		Wos	000275580600002	Publication Date	2010-01-15
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0926-860X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	4.339	Times cited	20	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 4.339; 2010 IF: 3.384
Call Number	UA @ lucian @ c:irua:81741			Serial	292
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Author	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	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
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Author	Morozov, V.A.; Arakcheeva, A.V.; Konovalova, V.V.; Pattison, P.; Chapuis, G.; Lebedev, O.I.; Fomichev, V.V.; Van Tendeloo, G.
Title	LiZnNb₄O_11.5 : a novel oxygen deficient compound in the Nb-rich part of the Li₂O-ZnO-Nb₂O₅ system			Type	A1 Journal article
Year	2010	Publication	Journal of solid state chemistry	Abbreviated Journal	J Solid State Chem
Volume	183	Issue	2	Pages	408-418
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	A novel lithium zinc niobium oxide LiZnNb(4)O(11.5) (LZNO) has been found in the Nb-rich part of Li(2)O-ZnO-Nb(2)O(5) system. LZNO, with an original alpha-PbO(2) related structure, has been synthesized by the routine ceramic technique and characterized by X-ray diffraction and transmission electron microscopy (TEM). Reflections belonging to the LZNO phase, observed in X-ray powder diffraction (XRPD) and electron diffraction, have been indexed as monoclinic with unit cell parameters a=17.8358(9)angstrom, b=15.2924(7)angstrom, c=5.0363(3)angstrom and gamma=96.607(5)degrees or as alpha-PbO(2)-like with lattice constants a=4.72420(3)angstrom, b=5.72780(3)angstrom, c=5.03320(3)angstrom, gamma=90.048(16)degrees and modulation vector q=0.3a+1.1b indicating a commensurately modulated alpha-PbO(2) related structure. The monoclinic cell is a supercell related to the latter. Using synchrotron powder diffraction data, the structure has been solved and refined as a commensurate modulation (superspace group P112(1)/n(alpha beta 0)00) as well as a supercell (space group P2(1)/b). The superspace description allows us to consider the LZNO structure as a member of the proposed alpha-PbO(2)-Z (3 + 1)D structure type, which unifies both incommensurately and commensurately modulated structures. HRTEM reveals several types of defects in LZNO and structural models for these defects are proposed. Two new phases in Li(2)O-ZnO-Nb(2)O(5) system are predicted on the basis of this detailed HRTEM analysis. (C) 2009 Elsevier Inc. All rights reserved.
Address
Corporate Author				Thesis
Publisher		Place of Publication	London	Editor
Language		Wos	000274497600020	Publication Date	2009-12-17
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	0022-4596;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	2.299	Times cited	9	Open Access
Notes	Iap-Vi			Approved	Most recent IF: 2.299; 2010 IF: 2.261
Call Number	UA @ lucian @ c:irua:95646			Serial	3542
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Author	Verlooy, P.L.H.; Robeyns, K.; van Meervelt, L.; Lebedev, O.I.; Van Tendeloo, G.; Martens, J.A.; Kirschhock, C.E.A.
Title	Synthesis and characterization of the new cyclosilicate hydrate (hexamethyleneimine)₄.[Si₈O₁₆(OH)₄].12H₂O			Type	A1 Journal article
Year	2010	Publication	Microporous and mesoporous materials: zeolites, clays, carbons and related materials	Abbreviated Journal	Micropor Mesopor Mat
Volume	130	Issue	1/3	Pages	14-20
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	A new cyclosilicate hydrate with composition (C6H14N)4·[Si8O16(OH)4]·12H2O was crystallized and the structure determined by single-crystal X-ray diffraction. The structure, described by the tetragonal space group I41/a, with unit cell dimensions of a = 39.2150(2) Å and c = 14.1553(2) Å, contains columns of hydrogen-bonded cubic octamer silicate anions. The space between silicate columns holds hydrogen-bonded water and protonated hexamethyleneimine molecules compensating the negative charge of the silicate. The crystal water can be removed resulting in a rearrangement of the columns into orthorhombic symmetry. Removal of the organic moiety causes amorphisation. Flash evacuation results in a new microporous material with pore volumes typical of a zeolite.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Amsterdam	Editor
Language		Wos	000275702600003	Publication Date	2009-10-14
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1387-1811;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	3.615	Times cited	5	Open Access
Notes				Approved	Most recent IF: 3.615; 2010 IF: 3.220
Call Number	UA @ lucian @ c:irua:82448			Serial	3418
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Author	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	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	Verlooy, P.; Aerts, A.; Lebedev, O.I.; Van Tendeloo, G.; Kirschhock, C.; Martens, J.A.
Title	Synthesis of highly stable pure-silica thin-walled hexagonally ordered mesoporous material			Type	A1 Journal article
Year	2009	Publication	Chemical communications	Abbreviated Journal	Chem Commun
Volume		Issue	28	Pages	4287-4289
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Hexagonally ordered mesoporous silica with a very narrow mesopore size distribution and exceptionally high stability paired with unusually thin pore walls was prepared using piperidine and cetyltrimethylammonium bromide.
Address
Corporate Author				Thesis
Publisher		Place of Publication	London	Editor
Language		Wos	000267808000040	Publication Date	2009-06-09
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1359-7345;1364-548X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	6.319	Times cited	17	Open Access
Notes				Approved	Most recent IF: 6.319; 2009 IF: 5.504
Call Number	UA @ lucian @ c:irua:77684			Serial	3457
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Author	Turner, S.; Lebedev, O.I.; Shenderova, O.; Vlasov, I.I.; Verbeeck, J.; Van Tendeloo, G.
Title	Determination of size, morphology, and nitrogen impurity location in treated detonation nanodiamond by transmission electron microscopy			Type	A1 Journal article
Year	2009	Publication	Advanced functional materials	Abbreviated Journal	Adv Funct Mater
Volume	19	Issue	13	Pages	2116-2124
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	Size, morphology, and nitrogen impurity location, all of which are all thought to be related to the luminescent properties of detonation nanodiamonds, are determined in several detonation nanodiamond samples using a combination of transmission electron microscopy techniques. Results obtained from annealed and cleaned detonation nanodiamond samples are compared to results from conventionally purified detonation nanodiamond. Detailed electron energy loss spectroscopy combined with model-based quantification provides direct evidence for the sp3 like embedding of nitrogen impurities into the diamond cores of all the studied nanodiamond samples. Simultaneously, the structure and morphology of the cleaned detonation nanodiamond particles are studied using high resolution transmission electron microscopy. The results show that the size and morphology of detonation nanodiamonds can be modified by temperature treatment and that by applying a special cleaning procedure after temperature treatment, nanodiamond particles with clean facets almost free from sp2 carbon can be prepared. These clean facets are clear evidence that nanodiamond cores are not necessarily in coexistence with a graphitic shell of non-diamond carbon.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Weinheim	Editor
Language		Wos	000268297800012	Publication Date	2009-05-12
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1616-301X;1616-3028;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	12.124	Times cited	100	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 12.124; 2009 IF: 6.990
Call Number	UA @ lucian @ c:irua:78261UA @ admin @ c:irua:78261			Serial	674
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Author	Barreca, D.; Gasparotto, A.; Maccato, C.; Tondello, E.; Lebedev, O.I.; Van Tendeloo, G.
Title	CVD of copper oxides from a \beta-diketonate diamine precursor: tailoring the nano-organization			Type	A1 Journal article
Year	2009	Publication	Crystal growth & design	Abbreviated Journal	Cryst Growth Des
Volume	9	Issue	5	Pages	2470-2480
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract	A copper(II) hexafluoroacetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate, hfa) adduct with N,N,N¡ä,N¡ä-tetramethylethylenediamine (TMEDA) [Cu(hfa)2¡¤TMEDA] is used for the first time as precursor for the chemical vapor deposition (CVD) of copper oxide nanosystems. The syntheses are carried out under both O2 and O2+H2O reaction atmospheres on Si(100) substrates, at temperatures ranging between 250 and 550 ¡ãC. Subsequently, the interrelations between the preparative conditions and the system composition, nanostructure, and morphology are elucidated by means of complementary analytical techniques [Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron and X-ray excited auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM)]. The obtained data revealed a gradual transformation from Cu2O, to Cu2O + CuO, to CuO nanosystems upon increasing the deposition temperature from 250 to 550 ¡ãC under both growth atmospheres. Such a phenomenon was accompanied by a progressive morphological evolution from continuous films to 1D hyperbranched nanostructures. Water vapor introduction in the deposition environment enabled to lower the deposition temperature and resulted in a higher aggregate interconnection, attributed to a higher density of nucleation centers.
Address
Corporate Author				Thesis
Publisher		Place of Publication		Editor
Language		Wos	000265892200066	Publication Date	2009-05-06
Series Editor		Series Title		Abbreviated Series Title
Series Volume		Series Issue		Edition
ISSN	1528-7483;1528-7505;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
Impact Factor	4.055	Times cited	60	Open Access
Notes	Esteem 026019			Approved	Most recent IF: 4.055; 2009 IF: 4.162
Call Number	UA @ lucian @ c:irua:77053			Serial	597
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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	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	Smeulders, G.; Meynen, V.; van Baelen, G.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Maes, B.U.W.; Cool, P.
Title	Rapid microwave-assisted synthesis of benzene bridged periodic mesoporous organosilicas			Type	A1 Journal article
Year	2009	Publication	Journal of materials chemistry	Abbreviated Journal	J Mater Chem
Volume	19	Issue	19	Pages	3042-3048
Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY)
Abstract	Following extended use in organic chemistry, microwave-assisted synthesis is gaining more importance in the field of inorganic chemistry, especially for the synthesis of nanoporous materials. It offers some major advantages such as a significant shortening of the synthesis time and an improved promotion of nucleation. In the research here reported, microwave technology is applied for the synthesis of benzene bridged PMOs (periodic mesoporous organosilicas). PMOs are one of the latest innovations in the field of hybrid ordered mesoporous materials and have attracted much attention because of their feasibility in electronics, catalysis, separation and sorption applications. The different synthesis steps (stirring, aging and extraction) of the classical PMO synthesis are replaced by microwave-assisted synthesis steps. The characteristics of the as-synthesized materials are evaluated by X-ray diffraction, N2-sorption, thermogravimetric analysis, scanning- and transmission electron microscopy. The microwave-assisted synthesis drastically reduces the synthesis time by more than 40 hours without any loss in structural properties, such as mesoscale and molecular ordering. The porosity of the PMO materials has even been improved by more than 25%. Moreover, the number of handling/transfer steps and amounts of chemicals and waste are drastically reduced. The study also shows that there is a clear time (1 to 3 hours) and temperature frame (373 K to 403 K) wherein synthesis of benzene bridged PMO is optimal. In conclusion, the microwave-assisted synthesis pathway allows an improved material to be obtained in a more economical way i.e. a much shorter time with fewer chemicals and less waste.
Address
Corporate Author				Thesis
Publisher		Place of Publication	Cambridge	Editor
Language		Wos	000265919300024	Publication Date	2009-03-17
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	20	Open Access
Notes	Fwo; Iwt			Approved	Most recent IF: NA
Call Number	UA @ lucian @ c:irua:76844			Serial	2810
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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	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
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