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Author van den Broek, W.; Van Aert, S.; van Dyck, D.
Title A model based atomic resolution tomographic algorithm Type A1 Journal article
Year (down) 2009 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 109 Issue 12 Pages 1485-1490
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Tomography with high angular annular dark field scanning transmission electron microscopy at atomic resolution can be greatly improved if one is able to take advantage of prior knowledge. In this paper we present a reconstruction technique that explicitly takes into account the microscope parameters and the atomic nature of the projected object. This results in a more accurate estimate of the atomic positions and in a good resistance to noise. The reconstruction is a maximum likelihood estimator of the object. Moreover, the limits to the precision have been explored, allowing for a prediction of the amount of expected noise in the reconstruction for a certain experimental setup. We believe that the proposed reconstruction technique can be generalized to other tomographic experiments.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000271840200010 Publication Date 2009-08-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 17 Open Access
Notes Approved Most recent IF: 2.843; 2009 IF: 2.067
Call Number UA @ lucian @ c:irua:78588 Serial 2097
Permanent link to this record
 
 
Author Eckert, M.; Neyts, E.; Bogaerts, A.
Title Modeling adatom surface processes during crystal growth: a new implementation of the Metropolis Monte Carlo algorithm Type A1 Journal article
Year (down) 2009 Publication CrystEngComm Abbreviated Journal Crystengcomm
Volume 11 Issue 8 Pages 1597-1608
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this paper, a new implementation of the Metropolis Monte Carlo (MMC) algorithm is presented. When combining the MMC model with a molecular dynamics (MD) code, crystal growth by plasma-enhanced chemical vapor deposition can be simulated. As the MD part simulates impacts of growth species onto the surface on a time scale of picoseconds, the MMC algorithm simulates the slower adatom surface processes. The implementation includes a criterion for the selection of atoms that are allowed to be displaced during the simulation, and a criterion of after how many MMC cycles the simulation is stopped. We performed combined MD-MMC simulations for hydrocarbon species that are important for the growth of ultrananocrystalline diamond (UNCD) films at partially hydrogenated diamond surfaces, since this implementation is part of a study of the growth mechanisms of (ultra)nanocrystalline diamond films. Exemplary for adatom arrangements during the growth of UNCD, the adatom surface behavior of C and C2H2 at diamond (111)1 × 1, C and C4H2 at diamond (111)1 × 1 and C3 at diamond (100)2 × 1 has been investigated. For all cases, the diamond crystal structure is pursued under the influence of MMC simulation. Additional longer time-scale MD simulations put forward very similar structures, verifying the MMC algorithm. Nevertheless, the MMC simulation time is typically one order of magnitude shorter than the MD simulation time.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000268184300021 Publication Date 2009-04-07
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 15 Open Access
Notes Approved Most recent IF: 3.474; 2009 IF: 4.183
Call Number UA @ lucian @ c:irua:77374 Serial 2106
Permanent link to this record
 
 
Author Magnus, W.; Brosens, F.; Sorée, B.
Title Modeling drive currents and leakage currents : a dynamic approach Type A1 Journal article
Year (down) 2009 Publication Journal of computational electronics Abbreviated Journal J Comput Electron
Volume 8 Issue 3/4 Pages 307-323
Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Abstract The dynamics of electrons and holes propagating through the nano-scaled channels of modern semiconductor devices can be seen as a widespread manifestation of non-equilibrium statistical physics and its ruling principles. In this respect both the devices that are pushing conventional CMOS technology towards the final frontiers of Moores law and the upcoming set of alternative, novel nanostructures grounded on entirely new concepts and working principles, provide an almost unlimited playground for assessing physical models and numerical techniques emerging from classical and quantum mechanical non-equilibrium theory. In this paper we revisit the Boltzmann as well as the WignerBoltzmann equation which offers a valuable platform to study transport of charge carriers taking part in drive currents. We focus on a numerical procedure that regained attention recently as an alternative tool to solve the time-dependent Boltzmann equation for inhomogeneous systems, such as the channel regions of field-effect transistors, and we discuss its extension to the WignerBoltzmann equation. Furthermore, we pay attention to the calculation of tunneling leakage currents. The latter typically occurs in nano-scaled transistors when part of the carrier distribution sustaining the drive current is found to tunnel into the gate due the presence of an ultra-thin insulating barrier separating the gate from the channel region. In particular, we discuss the paradox related to the very existence of leakage currents established by electrons occupying quasi-bound states, while the (real) wave functions of the latter cannot carry net currents. Finally, we describe a simple model to resolve the paradox as well as to estimate gate currents provided the local carrier generation rates largely exceed the tunneling rates.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos 000208236100009 Publication Date 2009-09-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1569-8025;1572-8137; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.526 Times cited 4 Open Access
Notes Approved Most recent IF: 1.526; 2009 IF: NA
Call Number UA @ lucian @ c:irua:89503 Serial 2110
Permanent link to this record
 
 
Author Ariskin, D.A.; Schweigert, I.V.; Alexandrov, A.L.; Bogaerts, A.; Peeters, F.M.
Title Modeling of chemical processes in the low pressure capacitive radio frequency discharges in a mixture of Ar/C2H2 Type A1 Journal article
Year (down) 2009 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 105 Issue 6 Pages 063305,1-063305,9
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We study the properties of a capacitive 13.56 MHz discharge with a mixture of Ar/C<sub>2</sub>H<sub>2</sub> taking into account the plasmochemistry and growth of heavy hydrocarbons. A hybrid model was developed to combine the kinetic description for electron motion and the fluid approach for negative and positive ion transports and plasmochemical processes. A significant change in plasma parameters related to injection of 5.8% portion of acetylene in argon was observed and analyzed. We found that the electronegativity of the mixture is about 30%. The densities of negatively and positively charged heavy hydrocarbons are sufficiently large to be precursors for the formation of nanoparticles in the discharge volume.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000264774000059 Publication Date 2009-03-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 21 Open Access
Notes Approved Most recent IF: 2.068; 2009 IF: 2.072
Call Number UA @ lucian @ c:irua:74496 Serial 2121
Permanent link to this record
 
 
Author Neyts, E.; Bogaerts, A.; van de Sanden, M.C.M.
Title Modeling PECVD growth of nanostructured carbon materials Type A1 Journal article
Year (down) 2009 Publication High temperature material processes Abbreviated Journal High Temp Mater P-Us
Volume 13 Issue 3/4 Pages 399-412
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We present here some of our modeling efforts for PECVD growth of nanostructured carbon materials with focus on amorphous hydrogenated carbon. Experimental data from an expanding thermal plasma setup were used as input for the simulations. Attention was focused both on the film growth mechanism, as well as on the hydrocarbon reaction mechanisms during growth of the films. It is found that the reaction mechanisms and sticking coefficients are dependent on the specific surface sites, and the structural properties of the growth radicals. The film growth results are in correspondence with the experiment. Furthermore, it is found that thin a-C:H films can be densified using an additional H-flux towards the substrate.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000274202300012 Publication Date 2010-02-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1093-3611; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:80991 Serial 2138
Permanent link to this record
 
 
Author Payette, C.; Partoens, B.; Yu, G.; Gupta, J.A.; Austing, D.G.; Nair, S.V.; Amaha, S.; Tarucha, S.
Title Modeling single-particle energy levels and resonance currents in a coherent electronic quantum dot mixer Type A1 Journal article
Year (down) 2009 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 94 Issue 22 Pages 222101,1-22101,3
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present model calculations based on a coherent tunneling picture, which reproduce well both the single-particle energy level position and the resonant current strength at two typical anticrossings, one involving two levels and the other three levels in a coherent mixer composed of two weakly coupled vertical quantum dots. An essential ingredient is the inclusion of higher degree terms to account for deviations from an ideal elliptical parabolic confining potential in realistic dots. We also calculate density plots of the mixed states for the modified potential.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000266674300024 Publication Date 2009-06-01
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 5 Open Access
Notes Approved Most recent IF: 3.411; 2009 IF: 3.554
Call Number UA @ lucian @ c:irua:77380 Serial 2139
Permanent link to this record
 
 
Author Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A.
Title Modified atomic scattering amplitudes and size effects on the 002 and 220 electron structure factors of multiple Ga1-xInxAs/GaAs quantum wells Type A1 Journal article
Year (down) 2009 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 105 Issue 8 Pages 084310,1-084310,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The modified atomic scattering amplitudes (MASAs) of mixed Ga<sub>1-x</sub>In<sub>x</sub>As, GaAs<sub>1-x</sub>N<sub>x</sub>, and InAs<sub>1-x</sub>N<sub>x</sub> are calculated using the density functional theory approach and the results are compared with those of the binary counterparts. The MASAs of N, Ga, As, and In for various scattering vectors in various chemical environments and in the zinc-blende structure are compared with the frequently used Doyle and Turner values. Deviation from the Doyle and Turner results is found for small scattering vectors (s<0.3 Å<sup>-1</sup>) and for these scattering vectors the MASAs are found to be sensitive to the orientation of the scattering vector and on the chemical environment. The chemical environment sensitive MASAs are used within zero pressure classical Metropolis Monte Carlo, finite temperature calculations to investigate the effect of well size on the electron 002 and 220 structure factors (SFs). The implications of the use of the 002 (200) spot for the quantification of nanostructured Ga<sub>1-x</sub>In<sub>x</sub>As systems are examined while the 220 SF across the well is evaluated and is found to be very sensitive to the in-plane static displacements.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000268064700149 Publication Date 2009-04-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record
Impact Factor 2.068 Times cited Open Access
Notes Fwo G.0425.05; Esteem 026019 Approved Most recent IF: 2.068; 2009 IF: 2.072
Call Number UA @ lucian @ c:irua:78282 Serial 2160
Permanent link to this record
 
 
Author Vast, L.; Carpentier, L.; Lallemand, F.; Colomer, J.-F.; Van Tendeloo, G.; Fonseca, A.; Nagy, J.B.; Mekhalif, Z.; Delhalle, J.
Title Multiwalled carbon nanotubes functionalized with 7-octenyltrichlorosilane and n-octyltrichlorosilane: dispersion in Sylgard®184 silicone and Youngs modulus Type A1 Journal article
Year (down) 2009 Publication Journal of materials science Abbreviated Journal J Mater Sci
Volume 44 Issue 13 Pages 3476-3482
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Sylgard®184/multiwalled carbon nanotube (MWNT) composites have been prepared by in situ polymerization using purified and functionalized multiwalled carbon nanotubes (f-MWNTs) as fillers. Surface modification of the MWNTs has been carried out by silanization with 7-octenyltrichlorosilane (7OTCS) and n-octyltrichlorosilane (nOTCS). The modification and dispersion of the carbon nanotubes in composites were characterized by X-ray photoelectron spectroscopy (XPS), transmission electron spectroscopy (TEM), and high-resolution transmission electron spectroscopy (HRTEM). Youngs modulus results were derived from indentation testing. It is shown that the terminal-vinyl group of 7OTCS molecules plays an essential role for both the dispersion of the f-MWNTs in the composite and its mechanical properties. At loading as low as 0.2 wt%, the Youngs modulus is shown to increase up to 50%. This is interpreted as resulting from a combination of the good compatibility in the forming silicone matrix of the MWNTs coated with a siloxane network, on the one hand, and the covalent links created between the terminal-vinyl groups and the host matrix in formation, on the other hand.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000267153200022 Publication Date 2009-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2461;1573-4803; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.599 Times cited 16 Open Access
Notes Iuap Approved Most recent IF: 2.599; 2009 IF: 1.471
Call Number UA @ lucian @ c:irua:77844 Serial 2245
Permanent link to this record
 
 
Author Vlasov, I.I.; Barnard, A.S.; Ralchenko, V.G.; Lebedev, O.I.; Kanzyuba, M.V.; Saveliev, A.V.; Konov, V.I.; Goovaerts, E.
Title Nanodiamond photoemitters based on strong narrow-band luminescence from silicon-vacancy defects Type A1 Journal article
Year (down) 2009 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 21 Issue 7 Pages 808-812
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Nanostructured and organic optical and electronic materials (NANOrOPT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000263737800012 Publication Date 2008-12-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648;1521-4095; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 98 Open Access
Notes Approved Most recent IF: 19.791; 2009 IF: NA
Call Number UA @ lucian @ c:irua:74513 Serial 2253
Permanent link to this record
 
 
Author Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M.
Title Neutral shallow donors near a metallic interface Type A1 Journal article
Year (down) 2009 Publication Microelectronics journal Abbreviated Journal Microelectron J
Volume 40 Issue 4/5 Pages 753-755
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effect of a metallic gate on the bound states of a shallow donor located near the gate is studied. We calculate the energy spectrum as a function of the distance between the metallic gate and the donor and find an anti-crossing behavior in the energy levels for certain distances. We show how a transverse electric field can tune the average position of the electron with respect to the metallic gate and the impurity.
Address
Corporate Author Thesis
Publisher Place of Publication Luton Editor
Language Wos 000265870200024 Publication Date 2009-02-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-2692; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.163 Times cited 1 Open Access
Notes Approved Most recent IF: 1.163; 2009 IF: 0.778
Call Number UA @ lucian @ c:irua:77029 Serial 2296
Permanent link to this record
 
 
Author Zhang, H.; Yang, J.-H.; Shpanchenko, R.V.; Abakumov, A.M.; Hadermann, J.; Clérac, R.; Dikarev, E.V.
Title New class of single-source precursors for the synthesis of main group-transition metal oxides: heterobimetallic Pb-Mn \beta-diketonates Type A1 Journal article
Year (down) 2009 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 48 Issue 17 Pages 8480-8488
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Heterometallic lead−manganese â-diketonates have been isolated in pure form by several synthetic methods that include solid-state and solution techniques. Two compounds with different Pb/Mn ratios, PbMn2(hfac)6 (1) and PbMn(hfac)4 (2) (hfac = hexafluoroacetylacetonate), can be obtained in quantitative yield by using different starting materials. Single crystal X-ray investigation revealed that the solid-state structure of 1 contains trinuclear molecules in which lead metal center is sandwiched between two [Mn(hfac)3] units, while 2 consists of infinite chains of alternating [Pb(hfac)2] and [Mn(hfac)2] fragments. The heterometallic structures are held together by strong Lewis acid−base interactions between metal atoms and diketonate ligands acting in chelating-bridging fashion. Spectroscopic investigation confirmed the retention of heterometallic structures in solutions of non-coordinating solvents as well as upon sublimation-deposition procedure. Thermal decomposition of heterometallic diketonates has been systematically investigated in a wide range of temperatures and annealing times. For the first time, it has been shown that thermal decomposition of heterometallic diketonates results in mixed-metal oxides, while both the structure of precursors and the thermolysis conditions have a significant influence on the nature of the resulting oxides. Five different Pb−Mn oxides have been detected by X-ray powder diffraction when studying the decomposition of 1 and 2 in the temperature range 500−800 °C. The phase that has been previously reported as Pb0.43MnO2.18 was synthesized in the pure form by decomposition of 1, and crystallographically characterized. The orthorhombic unit cell parameters of this oxide, obtained by electron diffraction technique, have been subsequently refined using X-ray powder diffraction data. Besides that, a previously unknown lead−manganese oxide has been obtained at low temperature decomposition and short annealing times. The parameters of its monoclinically distorted unit cell have been determined. The EDX analysis revealed that this compound has a Pb/Mn ratio close to 1:4 and contains no appreciable amount of fluorine.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000269313500056 Publication Date 2009-08-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 28 Open Access
Notes Approved Most recent IF: 4.857; 2009 IF: 4.657
Call Number UA @ lucian @ c:irua:78486 Serial 2308
Permanent link to this record
 
 
Author Caignaert, V.; Abakumov, A.M.; Pelloquin, D.; Pralong, V.; Maignan, A.; Van Tendeloo, G.; Raveau, B.
Title A new mixed-valence ferrite with a cubic structure, YBaFe4O7: spin-glass-like behavior Type A1 Journal article
Year (down) 2009 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 21 Issue 6 Pages 1116-1122
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new mixed-valence ferrite, YBaFe4O7, has been synthesized. Its unique cubic structure, with a = 8.9595(2) Å, is closely related to that of the hexagonal 114 oxides YBaCo4O7 and CaBaFe4O7. It consists of corner-sharing FeO4 tetrahedra, forming triangular and kagome layers parallel to (111)C. In fact, the YBaFe4O7 and CaBaFe4O7 structures can be described as two different ccc and chch close packings of [BaO3]∞ and [O4]∞ layers, respectively, whose tetrahedral cavities are occupied by Fe2+/Fe3+ cations. The local structure of YBaFe4O7 is characterized by a large amount of stacking faults originating from the presence of hexagonal layers in the ccc cubic close-packed YBaFe4O7 structure. In this way, they belong to the large family of spinels and hexagonal ferrites studied for their magnetic properties. Differently from all the ferrites and especially from CaBaFe4O7, which are ferrimagnetic, YBaFe4O7 is an insulating spin glass with Tg = 50 K.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000264310900019 Publication Date 2009-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 39 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2009 IF: 5.368
Call Number UA @ lucian @ c:irua:76432 Serial 2325
Permanent link to this record
 
 
Author Neyts, E.; Eckert, M.; Mao, M.; Bogaerts, A.
Title Numerical simulation of hydrocarbon plasmas for nanoparticle formation and the growth of nanostructured thin films Type A1 Journal article
Year (down) 2009 Publication Plasma physics and controlled fusion Abbreviated Journal Plasma Phys Contr F
Volume 51 Issue Pages 124034,1-124034,8
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract This paper outlines two different numerical simulation approaches, carried out by our group, used for describing hydrocarbon plasmas in their applications for either nanoparticle formation in the plasma or the growth of nanostructured thin films, such as nanocrystalline diamond (NCD). A plasma model based on the fluid approach is utilized to study the initial mechanisms giving rise to nanoparticle formation in an acetylene plasma. The growth of NCD is investigated by molecular dynamics simulations, describing the interaction of the hydrocarbon species with a substrate.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000271940800045 Publication Date 2009-11-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0741-3335;1361-6587; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.392 Times cited 2 Open Access
Notes Approved Most recent IF: 2.392; 2009 IF: 2.409
Call Number UA @ lucian @ c:irua:79132 Serial 2405
Permanent link to this record
 
 
Author Neyts, E.C.; Bogaerts, A.
Title Numerical study of the size-dependent melting mechanisms of nickel nanoclusters Type A1 Journal article
Year (down) 2009 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 113 Issue 7 Pages 2771-2776
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Molecular dynamics simulations were used to investigate the size-dependent melting mechanism of nickel nanoclusters of various sizes. The melting process was monitored by the caloric curve, the overall cluster Lindemann index, and the atomic Lindemann index. Size-dependent melting temperatures were determined, and the correct linear dependence on inverse diameter was recovered. We found that the melting mechanism gradually changes from dynamic coexistence melting to surface melting with increasing cluster size. These findings are of importance in better understanding carbon nanotube growth by catalytic chemical vapor deposition as the phase state of the catalyst nanoparticle codetermines the growth mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited Open Access
Notes Approved Most recent IF: 4.536; 2009 IF: 4.224
Call Number UA @ lucian @ c:irua:76495 Serial 2410
Permanent link to this record
 
 
Author Kolev, I.; Bogaerts, A.
Title Numerical study of the sputtering in a dc magnetron Type A1 Journal article
Year (down) 2009 Publication Journal of vacuum science and technology: A: vacuum surfaces and films Abbreviated Journal J Phys Chem C
Volume 27 Issue 1 Pages 20-28
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Molecular dynamics simulations were used to investigate the size-dependent melting mechanism of nickel nanoclusters of various sizes. The melting process was monitored by the caloric curve, the overall cluster Lindemann index, and the atomic Lindemann index. Size-dependent melting temperatures were determined, and the correct linear dependence on inverse diameter was recovered. We found that the melting mechanism gradually changes from dynamic coexistence melting to surface melting with increasing cluster size. These findings are of importance in better understanding carbon nanotube growth by catalytic chemical vapor deposition as the phase state of the catalyst nanoparticle codetermines the growth mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000263299600018 Publication Date 2009-02-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 66 Open Access
Notes Approved Most recent IF: 4.536; 2009 IF: 4.224
Call Number UA @ lucian @ c:irua:71634 Serial 2411
Permanent link to this record
 
 
Author Koblischka, M.R.; Winter, M.; Das, P.; Koblischka-Veneva, A.; Muralidhar, M.; Wolf, T.; Babu, N.H.; Turner, S.; Van Tendeloo, G.; Hartmann, U.
Title Observation of nanostripes and -clusters in (Nd, EuGd)Ba2Cu3Ox superconductors Type A1 Journal article
Year (down) 2009 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 469 Issue 4 Pages 168-176
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Nanostripes are observed in melt-textured and single-crystalline samples of the ternary light rare earth (LRE)-compound (Nd0.33Eu0.33Gd0.33)Ba2Cu3Ox (NEG) by means of atomic force microscopy, scanning tunnelling microscopy at ambient conditions, combined with transmission electron microscopy and electron backscatter diffraction. This enables the observation of several important features: The nanostripes are formed by chains of nanoclusters, representing the LRE/Ba substitution. The dimensions of the nanostripes are similar for both types of NEG samples. The periodicity of the nanostripes is found to range between 40 and 60 nm; the shape of the nanoclusters is elliptic with a major axis length between 300 and 500 nm and a minor axis length of about 30150 nm. The stripes are filling effectively the space in between the twin boundaries. Concerning the flux pinning, the nanoclusters are the important pinning sites, not the nanostripes themselves.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000264657100008 Publication Date 2009-01-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 6 Open Access
Notes Approved Most recent IF: 1.404; 2009 IF: 0.723
Call Number UA @ lucian @ c:irua:76403 Serial 2418
Permanent link to this record
 
 
Author Martens, T.; Brok, W.J.M.; van Dijk, J.; Bogaerts, A.
Title On the regime transitions during the formation of an atmospheric pressure dielectric barrier glow discharge Type A1 Journal article
Year (down) 2009 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 42 Issue 12 Pages 122002,1-122002,5
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The atmospheric pressure dielectric barrier discharge in helium is a pulsed discharge in nature. If during the electrical current pulse a glow discharge is reached, then this pulse will last only a few microseconds in operating periods of sinusoidal voltage with lengths of about 10 to 100 µs. In this paper we demonstrate that right before a glow discharge is reached, the discharge very closely resembles the commonly assumed Townsend discharge structure, but actually contains some significant differing features and hence should not be considered as a Townsend discharge. In order to clarify this, we present calculation results of high time and space resolution of the pulse formation. The results indicate that indeed a maximum of ionization is formed at the anode, but that the level of ionization remains high and that the electric field at that time is significantly disturbed. Our results also show where this intermediate structure comes from.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000266639300002 Publication Date 2009-05-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 21 Open Access
Notes Approved Most recent IF: 2.588; 2009 IF: 2.083
Call Number UA @ lucian @ c:irua:76458 Serial 2450
Permanent link to this record
 
 
Author Yang, X.-Y.; Li, Y.; Van Tendeloo, G.; Xiao, F.-S.; Su, B.-L.
Title One-pot synthesis of catalytically stable and active nanoreactors: encapsulation of size-controlled nanoparticles within a hierarchically macroporous core@ordered mesoporous shell system Type A1 Journal article
Year (down) 2009 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 21 Issue 13 Pages 1368-1372
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Size-controlled, catalytically active nanoparticles are successfully encapsulated in a one-pot synthesis to form novel hierarchical macroporous core@mesoporous shell structures, where macroporous cores are connected by uniform and ordered mesoporous channels. Most importantly, the encapsulated nanoparticles can be used as nanoreactors, with high activities and excellent long-term recycling stability.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000265432700011 Publication Date 2009-01-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648;1521-4095; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 61 Open Access
Notes Iap Approved Most recent IF: 19.791; 2009 IF: NA
Call Number UA @ lucian @ c:irua:77316 Serial 2466
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Author Dhong, H.M.; Zhang, J.; Peeters, F.M.; Xu, W.
Title Optical conductance and transmission in bilayer graphene Type A1 Journal article
Year (down) 2009 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 106 Issue 4 Pages 043103,1-043103,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a theoretical study of the optoelectronic properties of bilayer graphene. The optical conductance and transmission coefficient are calculated using the energy-balance equation derived from a Boltzmann equation for an air/graphene/dielectric-wafer system. For short wavelengths (<0.2 µm), we obtain the universal optical conductance =e2/(2). Interestingly, there exists an optical absorption window in the wavelength range 10100 µm, which is induced by different transition energies required for inter- and intra-band optical absorptions in the presence of the MossBurstein effect. As a result, the position and width of this absorption window depend sensitively on temperature, carrier density, and sample mobility of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000270083800004 Publication Date 2009-08-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 11 Open Access
Notes Approved Most recent IF: 2.068; 2009 IF: 2.072
Call Number UA @ lucian @ c:irua:79315 Serial 2472
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Author Cao, S.; Tirry, W.; van den Broek, W.; Schryvers, D.
Title Optimization of a FIB/SEM slice-and-view study of the 3D distribution of Ni4Ti3 precipitates in NiTi Type A1 Journal article
Year (down) 2009 Publication Journal of microscopy Abbreviated Journal J Microsc-Oxford
Volume 233 Issue 1 Pages 61-68
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract The 3D morphology and distribution of lenticular Ni4Ti3 precipitates in the austenitic B2 matrix of a binary Ni51Ti49 alloy has been investigated by a slice-and-view procedure in a dual-beam focused ion beam/scanning electron microscope system. Due to the weak contrast of the precipitates, proper imaging conditions need to be selected first to allow for semi-automated image treatment. Knowledgeable imaging is further needed to ensure that all variants of the precipitates are observed with equal probability, regardless of sample orientation. Finally, a volume ratio of 10.2% for the Ni4Ti3 precipitates could be calculated, summed over all variants, which yields a net composition of Ni50.27Ti49.73 for the matrix, leading to an increase of 125 degrees for the martensitic start temperature. Also, the expected relative orientation of the different variants of the precipitates could be confirmed.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000262511900008 Publication Date 2009-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2720;1365-2818; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.692 Times cited 22 Open Access
Notes Multimat Fwo; G0465.05 Approved Most recent IF: 1.692; 2009 IF: 1.612
Call Number UA @ lucian @ c:irua:76026 Serial 2486
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Author Lindner, H.; Autrique, D.; Garcia, C.C.; Niemax, K.; Bogaerts, A.
Title Optimized transport setup for high repetition rate pulse-separated analysis in laser ablation-inductively coupled plasma mass spectrometry Type A1 Journal article
Year (down) 2009 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 81 Issue 11 Pages 4241-4248
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract An optimized laser ablation setup, proposed for high repetition rate inductively coupled plasma mass spectrometry (ICPMS) analyses such as 2D imaging or depth profiling, is presented. For such applications, the particle washout time needs to be as short as possible to allow high laser pulse frequencies for reduced analysis time. Therefore, it is desirable to have an ablation setup that operates as a laminar flow reactor (LFR). A top-down strategy was applied that resulted in the present design. In the first step, a previously applied ablation setup was analyzed on the basis of computational fluid dynamics (CFD) results presented by D. Autrique et al. (Spectrochim. Acta, B 2008, 63, 257−270). By means of CFD simulations, the design was modified in such a way that it operated in the LFR regime. Experimental results demonstrate that the current design can indeed be regarded as an LFR. Furthermore, the operation under LFR conditions allowed some insight into the initial radial concentration distribution if the experimental ICPMS signal and analytical expressions are taken into account. Recommendations for a modified setup for more resilient spatial distributions are given. With the present setup, a washout time of 140 ms has been achieved for a 3% signal area criterion. Therefore, 7 Hz repetition rates can be applied with the present setup. Using elementary formulas of the analytical model, an upper bound for the washout times for similar setups can be predicted. The authors believe that the presented setup geometry comes close to the achievable limit for reliable short washout times.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000266601800014 Publication Date 2009-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 18 Open Access
Notes Approved Most recent IF: 6.32; 2009 IF: 5.214
Call Number UA @ lucian @ c:irua:76935 Serial 2492
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Author Kirschhock, C.E.A.; Liang, D.; Van Tendeloo, G.; Fécant, A.; Hastoye, G.; Vanbutsele, G.; Bats, N.; Guillon, E.; Martens, J.A.
Title Ordered end-member of ZSM-48 zeolite family Type A1 Journal article
Year (down) 2009 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 21 Issue 2 Pages 371-380
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract ZSM-48 and related zeolites are considered to be highly disordered structures. Different polytypes can be clearly distinguished by simulation of high-resolution electron microscopy images. Synthesis of phase-pure polytypes was attempted. One of the investigated samples crystallized via seeding designated as COK-8 consisted of nanoscopic, needlelike crystals with a very large length/width ratio, growing along the pore direction. These specimens are phase-pure polytype 6 (PT6, numbering according to Lobo and van Koningsveld). Aggregates of these nanoneedles occasionally contained a second polytype: PT1. The latter polytype occurred more abundantly in larger crystal rods in an IZM-1 sample crystallized in ethylene glycol. Here too, the isolated crystallites mainly consist of large, defect-free regions of PT6. A simulation of polytype lattice energies offers a rational explanation for the observed polytypical intergrowth formation.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000262605200026 Publication Date 2008-12-30
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 30 Open Access
Notes Fwo; Goa Approved Most recent IF: 9.466; 2009 IF: 5.368
Call Number UA @ lucian @ c:irua:76032 Serial 2503
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Author Lamoen, D.; March, N.H.
Title Orientational disorder in some molecular solids in relation to the boson peak in glasses Type A1 Journal article
Year (down) 2009 Publication Physics letters : A Abbreviated Journal Phys Lett A
Volume 373 Issue 7 Pages 799-800
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Orientational disorder in some molecular solids is discussed in relation to the emphasis placed on transverse vibrational modes in glasses as the origin of the observed boson peak in two very recent contributions in Nature Materials. In particular, facts are here presented for (i) CH4, (ii) C60 and (iii) ethanol in their solid phases for (a) specific heat and (b) neutron scattering. The results for ethanol in particular do not fit in with the interpretation of the boson peak in terms of transverse acoustic phonons in disordered systems. Glasses will therefore have to be separated into at least two classes where the physical interpretation of the boson peak is concerned.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000263515500020 Publication Date 2009-01-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0375-9601; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.772 Times cited 3 Open Access
Notes Bof Approved Most recent IF: 1.772; 2009 IF: 2.009
Call Number UA @ lucian @ c:irua:72917 Serial 2516
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Author Verberck, B.; Vliegenthart, G.A.; Gompper, G.
Title Orientational ordering in solid C60 fullerene-cubane Type A1 Journal article
Year (down) 2009 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 130 Issue 15 Pages 154510,1-154510,14
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the structure and phase behavior of fullerene-cubane C60·C8H8 by Monte Carlo simulation. Using a simple potential model capturing the icosahedral and cubic symmetries of its molecular constituents, we reproduce the experimentally observed phase transition from a cubic to an orthorhombic crystal lattice and the accompanying rotational freezing of the C60 molecules. We elaborate a scheme to identify the low-temperature orientations of individual molecules and to detect a pattern of orientational ordering similar to the arrangement of C60 molecules in solid C60. Our configuration of orientations supports a doubled periodicity along one of the crystal axes.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000265486300036 Publication Date 2009-04-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 8 Open Access
Notes Approved Most recent IF: 2.965; 2009 IF: 3.093
Call Number UA @ lucian @ c:irua:77258 Serial 2519
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Author Abakumov, A.M.; Hadermann, J.; Tsirlin, A.A.; Tan, H.; Verbeeck, J.; Zhang, H.; Dikarev, E.V.; Shpanchenko, R.V.; Antipov, E.V.
Title Original close-packed structure and magnetic properties of the Pb4Mn9O20 manganite Type A1 Journal article
Year (down) 2009 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 182 Issue 8 Pages 2231-2238
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of the Pb4Mn9O20 compound (previously known as Pb0.43MnO2.18) was solved from powder X-ray diffraction, electron diffraction, and high resolution electron microscopy data (S.G. Pnma, a=13.8888(2) Å, b=11.2665(2) Å, c=9.9867(1) Å, RI=0.016, RP=0.047). The structure is based on a 6H (cch)2 close packing of pure oxygen h-type (O16) layers alternating with mixed c-type (Pb4O12) layers. The Mn atoms occupy octahedral interstices formed by the oxygen atoms of the close-packed layers. The MnO6 octahedra share edges within the layers, whereas the octahedra in neighboring layers are linked through corner sharing. The relationship with the closely related Pb3Mn7O15 structure is discussed. Magnetization measurements reveal a peculiar magnetic behavior with a phase transition at 52 K, a small net magnetization below the transition temperature, and a tendency towards spin freezing.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000269066400035 Publication Date 2009-06-12
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 5 Open Access
Notes The authors are grateful to Christoph Geibel for the help in magnetization measurements. A.Ts. acknowledges MPI CKS for hospitality and financial support during the stay. E.D. thanks the National Science Foundation (CHE-0718900) for financial support. This work was supported by the Russian Foundation of Basic Research (RFBR Grants 07-03-00664-a, 06-03-90168-a and 07-03-00890-a). The authors acknowledge financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. Approved Most recent IF: 2.299; 2009 IF: 2.340
Call Number UA @ lucian @ c:irua:78935UA @ admin @ c:irua:78935 Serial 2529
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Author Bultinck, E.; Mahieu, S.; Depla, D.; Bogaerts, A.
Title Particle-in-cell/Monte Carlo collisions model for the reactive sputter deposition of nitride layers Type A1 Journal article
Year (down) 2009 Publication Plasma processes and polymers Abbreviated Journal Plasma Process Polym
Volume 6 Issue S:1 Pages S784-S788
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A 2d3v Particle-in-cell/Monte Carlo collisions (PIC/MCC) model was constructed for an Ar/N2 reactive gas mixture in a magnetron discharge. A titanium target was used, in order to study the sputter deposition of a TiNx thin film. Cathode currents and voltages were calculated self-consistently and compared with experiments. Also, ion fluxes to the cathode were calculated, which cause sputtering of the target. The sputtered atom fluxes from the target, and to the substrate were calculated, in order to visualize the deposition of the TiNx film.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000272302900149 Publication Date 2009-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1612-8850; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.846 Times cited 2 Open Access
Notes Approved Most recent IF: 2.846; 2009 IF: 4.037
Call Number UA @ lucian @ c:irua:79364 Serial 2558
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Author Bultinck, E.; Bogaerts, A.
Title Particle-in-cell/Monte Carlo collisions treatment of an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx films Type A1 Journal article
Year (down) 2009 Publication New journal of physics Abbreviated Journal New J Phys
Volume 11 Issue Pages 103010-103010,24
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The physical processes in an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx thin films were simulated with a 2d3v particle-in-cell/Monte Carlo collisions (PIC/MCC) model. The plasma species taken into account are electrons, Ar+ ions, fast Arf atoms, metastable Arm* atoms, Ti+ ions, Ti atoms, O+ ions, O2+ ions, O− ions and O atoms. This model accounts for plasmatarget interactions, such as secondary electron emission and target sputtering, and the effects of target poisoning. Furthermore, the deposition process is described by an analytical surface model. The influence of the O2/Ar gas ratio on the plasma potential and on the species densities and fluxes is investigated. Among others, it is shown that a higher O2 pressure causes the region of positive plasma potential and the O− density to be more spread, and the latter to decrease. On the other hand, the deposition rates of Ti and O are not much affected by the O2/Ar proportion. Indeed, the predicted stoichiometry of the deposited TiOx film approaches x=2 for nearly all the investigated O2/Ar proportions.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000270820900001 Publication Date 2009-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.786 Times cited 24 Open Access
Notes Approved Most recent IF: 3.786; 2009 IF: 3.312
Call Number UA @ lucian @ c:irua:78326 Serial 2559
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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 (down) 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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Author Peelaers, H.; Partoens, B.; Peeters, F.M.
Title Phonon band structure of Si nanowires: a stability analysis Type A1 Journal article
Year (down) 2009 Publication Nano letters Abbreviated Journal Nano Lett
Volume 9 Issue 1 Pages 107-111
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present full ab initio calculations of the phonon band structure of thin Si nanowires oriented along the [110] direction. Using these phonon dispersion relations, we investigate the structural stability of these wires. We found that all studied wires were stable also when doped with either B or P, if the unit cell was taken sufficiently large along the wire axis. The evolution of the phonon dispersion relations and of the sound velocities with respect to the wire diameters is discussed. Softening is observed for acoustic modes and hardening for optical phonon modes with increasing wire diameters.
Address
Corporate Author Thesis
Publisher Place of Publication Washington Editor
Language Wos 000262519100020 Publication Date 2008-12-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 51 Open Access
Notes Approved Most recent IF: 12.712; 2009 IF: 9.991
Call Number UA @ lucian @ c:irua:76022 Serial 2601
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Author Peelaers, H.; Partoens, B.; Peeters, F.M.
Title Phonon band structures of Si nanowires Type A1 Journal article
Year (down) 2009 Publication AIP conference proceedings Abbreviated Journal
Volume 1199 Issue Pages 323-324
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present full ab initio calculations of the phonon band structure of thin Si nanowires oriented along the [110] direction. Using these phonon dispersion relations we investigate the structural stability of these wires. We found that all studied wires were stable also when doped with either B or P, if the unit cell was taken sufficiently large along the wire axis. The evolution of the phonon dispersion relations and of the sound velocities with respect to the wire diameters is discussed. Softening is observed for acoustic modes and hardening for optical phonon modes with increasing wire diameters.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000281590800153 Publication Date 2010-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:84891 Serial 2602
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