Records |
Author |
Boullay, P.; David, A.; Sheets, W.C.; Lüders, U.; Prellier, W.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.; Gatel, C.; Vincze, G.; Radi, Z. |
Title |
Microstructure and interface studies of LaVO3/SrVO3 superlattices |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
12 |
Pages |
125403-125403,6 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The structure and interface characteristics of (LaVO3)6m(SrVO3)m superlattices deposited on a (100)-SrTiO3 substrate were studied using transmission electron microscopy (TEM). Cross-section TEM studies revealed that both LaVO3 (LVO) and SrVO3 (SVO) layers are good single-crystal quality and epitaxially grown with respect to the substrate. It is evidenced that LVO layers are made of two orientational variants of a distorted perovskite compatible with bulk LaVO3, while SVO layers suffers from a tetragonal distortion due to the substrate-induced stain. Electron energy loss spectroscopy investigations indicate changes in the fine structure of the V L23 edge, related to a valence change between the LaVO3 and the SrVO3 layers. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000288160300006 |
Publication Date |
2011-03-09 |
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 |
26 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:88648UA @ admin @ c:irua:88648 |
Serial |
2054 |
Permanent link to this record |
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|
|
Author |
Jorissen, K.; Rehr, J.J.; Verbeeck, J. |
Title |
Multiple scattering calculations of relativistic electron energy loss spectra |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
15 |
Pages |
155108,1-155108,6 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A generalization of the real-space Greens-function approach is presented for ab initio calculations of relativistic electron energy loss spectra (EELS) which are particularly important in anisotropic materials. The approach incorporates relativistic effects in terms of the transition tensor within the dipole-selection rule. In particular, the method accounts for relativistic corrections to the magic angle in orientation resolved EELS experiments. The approach is validated by a study of the graphite C K edge, for which we present an accurate magic angle measurement consistent with the predicted value. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000277210500038 |
Publication Date |
2010-04-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
24 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:82805UA @ admin @ c:irua:82805 |
Serial |
2230 |
Permanent link to this record |
|
|
|
Author |
Van Aert, S.; Verbeeck, J.; Erni, R.; Bals, S.; Luysberg, M.; van Dyck, D.; Van Tendeloo, G. |
Title |
Quantitative atomic resolution mapping using high-angle annular dark field scanning transmission electron microscopy |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
109 |
Issue |
10 |
Pages |
1236-1244 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
A model-based method is proposed to relatively quantify the chemical composition of atomic columns using high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. The method is based on a quantification of the total intensity of the scattered electrons for the individual atomic columns using statistical parameter estimation theory. In order to apply this theory, a model is required describing the image contrast of the HAADF STEM images. Therefore, a simple, effective incoherent model has been assumed which takes the probe intensity profile into account. The scattered intensities can then be estimated by fitting this model to an experimental HAADF STEM image. These estimates are used as a performance measure to distinguish between different atomic column types and to identify the nature of unknown columns with good accuracy and precision using statistical hypothesis testing. The reliability of the method is supported by means of simulated HAADF STEM images as well as a combination of experimental images and electron energy-loss spectra. It is experimentally shown that statistically meaningful information on the composition of individual columns can be obtained even if the difference in averaged atomic number Z is only 3. Using this method, quantitative mapping at atomic resolution using HAADF STEM images only has become possible without the need of simultaneously recorded electron energy loss spectra. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000270015200004 |
Publication Date |
2009-05-28 |
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 |
166 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
Call Number |
UA @ lucian @ c:irua:78585UA @ admin @ c:irua:78585 |
Serial |
2748 |
Permanent link to this record |
|
|
|
Author |
Tan, H.; Lebedev, O.I.; McLaughlin, A.C.; Van Tendeloo, G. |
Title |
The superstructure and superconductivity of Ru1222 based RuSr2Gd2-x-yYyCexCu2O10-\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 |
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Corporate Author |
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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 ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.878; 2010 IF: 2.402 |
Call Number |
UA @ lucian @ c:irua:95553 |
Serial |
3385 |
Permanent link to this record |
|
|
|
Author |
Goris, B.; van Huis, M.A.; Bals, S.; Zandbergen, H.W.; Manna, L.; Van Tendeloo, G. |
Title |
Thermally induced structural and morphological changes of CdSe/CdS octapods |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Small |
Abbreviated Journal |
Small |
Volume |
8 |
Issue |
6 |
Pages |
937-942 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Branched nanostructures are of great interest because of their promising optical and electronic properties. For successful and reliable integration in applications such as photovoltaic devices, the thermal stability of the nanostructures is of major importance. Here the different domains (CdSe cores, CdS pods) of the heterogeneous octapods are shown to have different thermal stabilities, and heating is shown to induce specific shape changes. The octapods are heated from room temperature to 700 °C, and investigated using (analytical and tomographic) transmission electron microscopy (TEM). At low annealing temperatures, pure Cd segregates in droplets at the outside of the octapods, indicating non-stochiometric composition of the octapods. Furthermore, the tips of the pods lose their faceting and become rounded. Further heating to temperatures just below the sublimation temperature induces growth of the zinc blende core at the expense of the wurtzite pods. At higher temperatures, (500700 °C), sublimation of the octapods is observed in real time in the TEM. Three-dimensional tomographic reconstructions reveal that the four pods pointing into the vacuum have a lower thermal stability than the four pods that are in contact with the support. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000301718800021 |
Publication Date |
2012-01-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1613-6810; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.643 |
Times cited |
20 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 8.643; 2012 IF: 7.823 |
Call Number |
UA @ lucian @ c:irua:95040 |
Serial |
3633 |
Permanent link to this record |
|
|
|
Author |
de Backer, A.; Martinez, G.T.; Rosenauer, A.; Van Aert, S. |
Title |
Atom counting in HAADF STEM using a statistical model-based approach : methodology, possibilities, and inherent limitations |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
134 |
Issue |
|
Pages |
23-33 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In the present paper, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. In order to count the number of atoms, it is assumed that the total scattered intensity scales with the number of atoms per atom column. These intensities are quantitatively determined using model-based statistical parameter estimation theory. The distribution describing the probability that intensity values are generated by atomic columns containing a specific number of atoms is inferred on the basis of the experimental scattered intensities. Finally, the number of atoms per atom column is quantified using this estimated probability distribution. The number of atom columns available in the observed STEM image, the number of components in the estimated probability distribution, the width of the components of the probability distribution, and the typical shape of a criterion to assess the number of components in the probability distribution directly affect the accuracy and precision with which the number of atoms in a particular atom column can be estimated. It is shown that single atom sensitivity is feasible taking the latter aspects into consideration. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000324474900005 |
Publication Date |
2013-05-17 |
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 |
48 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; Esteem2; FP 2007-2013; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:109916 |
Serial |
162 |
Permanent link to this record |
|
|
|
Author |
Bertoni, G.; Verbeeck, J.; Brosens, F. |
Title |
Fitting the momentum dependent loss function in EELS |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Microscopy research and technique |
Abbreviated Journal |
Microsc Res Techniq |
Volume |
74 |
Issue |
3 |
Pages |
212-218 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Theory of quantum systems and complex systems |
Abstract |
Momentum dependent inelastic plasmon scattering can be measured by electron energy loss in a transmission electron microscope. From energy filtered diffraction, the characteristic angle of scattering and the cutoff angle are measured, using a thin film of aluminum as a model test. Rather than deconvolving the data (as done in previous works), a fitting technique is used to extract the loss function from angular resolved spectra, starting from a simple model simulation. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000288095200002 |
Publication Date |
2010-07-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1059-910X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.147 |
Times cited |
6 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Esteem; Iap; Goa |
Approved |
Most recent IF: 1.147; 2011 IF: 1.792 |
Call Number |
UA @ lucian @ c:irua:88782UA @ admin @ c:irua:88782 |
Serial |
1222 |
Permanent link to this record |
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|
|
Author |
den Dekker, A.J.; Gonnissen, J.; de Backer, A.; Sijbers, J.; Van Aert, S. |
Title |
Estimation of unknown structure parameters from high-resolution (S)TEM images : what are the limits? |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
134 |
Issue |
|
Pages |
34-43 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Statistical parameter estimation theory is proposed as a quantitative method to measure unknown structure parameters from electron microscopy images. Images are then purely considered as data planes from which structure parameters have to be determined as accurately and precisely as possible using a parametric statistical model of the observations. For this purpose, an efficient algorithm is proposed for the estimation of atomic column positions and intensities from high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. Furthermore, the so-called CramérRao lower bound (CRLB) is reviewed to determine the limits to the precision with which continuous parameters such as atomic column positions and intensities can be estimated. Since this lower bound can only be derived for continuous parameters, alternative measures using the principles of detection theory are introduced for problems concerning the estimation of discrete parameters such as atomic numbers. An experimental case study is presented to show the practical use of these measures for the optimization of the experiment design if the purpose is to decide between the presence of specific atom types using STEM images. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000324474900006 |
Publication Date |
2013-06-01 |
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 |
31 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; FP 2007-2013; Esteem2; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:109240 |
Serial |
1083 |
Permanent link to this record |
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|
|
Author |
Martinez, G.T.; Rosenauer, A.; de Backer, A.; Verbeeck, J.; Van Aert, S. |
Title |
Quantitative composition determination at the atomic level using model-based high-angle annular dark field scanning transmission electron microscopy |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
137 |
Issue |
|
Pages |
12-19 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
High angle annular dark field scanning transmission electron microscopy (HAADF STEM) images provide sample information which is sensitive to the chemical composition. The image intensities indeed scale with the mean atomic number Z. To some extent, chemically different atomic column types can therefore be visually distinguished. However, in order to quantify the atomic column composition with high accuracy and precision, model-based methods are necessary. Therefore, an empirical incoherent parametric imaging model can be used of which the unknown parameters are determined using statistical parameter estimation theory (Van Aert et al., 2009, [1]). In this paper, it will be shown how this method can be combined with frozen lattice multislice simulations in order to evolve from a relative toward an absolute quantification of the composition of single atomic columns with mixed atom types. Furthermore, the validity of the model assumptions are explored and discussed. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000331092200003 |
Publication Date |
2013-11-09 |
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 |
74 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; FP7; ERC Countatoms; ESTEEM2; esteem2_ta |
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
Call Number |
UA @ lucian @ c:irua:111579UA @ admin @ c:irua:111579 |
Serial |
2749 |
Permanent link to this record |
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|
|
Author |
Croitoru, M.D.; van Dyck, D.; Van Aert, S.; Bals, S.; Verbeeck, J. |
Title |
An efficient way of including thermal diffuse scattering in simulation of scanning transmission electron microscopic images |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
106 |
Issue |
10 |
Pages |
933-940 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Vision lab |
Abstract |
We propose an improved image simulation procedure for atomic-resolution annular dark-field scanning transmission electron microscopy (STEM) based on the multislice formulation, which takes thermal diffuse scattering fully into account. The improvement with regard to the classical frozen phonon approach is realized by separating the lattice configuration statistics from the dynamical scattering so as to avoid repetitive calculations. As an example, the influence of phonon scattering on the image contrast is calculated and investigated. STEM image simulation of crystals can be applied with reasonable computing times to problems involving a large number of atoms and thick or large supercells. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000240397200006 |
Publication Date |
2006-05-10 |
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 |
18 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Fwo-V |
Approved |
Most recent IF: 2.843; 2006 IF: 1.706 |
Call Number |
UA @ lucian @ c:irua:87604UA @ admin @ c:irua:87604 |
Serial |
876 |
Permanent link to this record |
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|
|
Author |
Müller, K.; Schowalter, M.; Jansen, J.; Tsuda, K.; Titantah, J.; Lamoen, D.; Rosenauer, A. |
Title |
Refinement of the 200 structure factor for GaAs using parallel and convergent beam electron nanodiffraction data |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
109 |
Issue |
7 |
Pages |
802-814 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We present a new method to measure structure factors from electron spot diffraction patterns recorded under almost parallel illumination in transmission electron microscopes. Bloch wave refinement routines have been developed to refine the crystal thickness, its orientation and structure factors by comparison of experimentally recorded and calculated intensities. Our method requires a modicum of computational effort, making it suitable for contemporary personal computers. Frozen lattice and Bloch wave simulations of GaAs diffraction patterns are used to derive optimised experimental conditions. Systematic errors are estimated from the application of the method to simulated diffraction patterns and rules for the recognition of physically reasonable initial refinement conditions are derived. The method is applied to the measurement of the 200 structure factor for GaAs. We found that the influence of inelastically scattered electrons is negligible. Additionally, we measured the 200 structure factor from zero loss filtered two-dimensional convergent beam electron diffraction patterns. The precision of both methods is found to be comparable and the results agree well with each other. A deviation of more than 20% from isolated atom scattering data is observed, whereas close agreement is found with structure factors obtained from density functional theory [A. Rosenauer, M. Schowalter, F. Glas, D. Lamoen, Phys. Rev. B 72 (2005), 085326-1], which account for the redistribution of electrons due to chemical bonding via modified atomic scattering amplitudes. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000266787900005 |
Publication Date |
2009-03-23 |
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 |
8 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; G.0425.05; Esteem; Ant 200611271505 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
Call Number |
UA @ lucian @ c:irua:77361 |
Serial |
2856 |
Permanent link to this record |
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|
|
Author |
Shabalovskaya, S.A.; Tian, H.; Anderegg, J.W.; Schryvers, D.U.; Carroll, W.U.; van Humbeeck, J. |
Title |
The influence of surface oxides on the distribution and release of nickel from Nitinol wires |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Biomaterials |
Abbreviated Journal |
Biomaterials |
Volume |
30 |
Issue |
4 |
Pages |
468-477 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The patterns of Ni release from Nitinol vary depending on the type of material (NiTi alloys with low or no processing versus commercial wires or sheets). A thick TiO2 layer generated on the wire surface during processing is often considered as a reliable barrier against Ni release. The present study of Nitinol wires with surface oxides resulting from production was conducted to identify the sources of Ni release and its distribution in the surface sublayers. The chemistry and topography of the surfaces of Nitinol wires drawn using different techniques were studied with XPS and SEM. The distribution of Ni into surface depth and the surface oxide thickness were evaluated using Auger spectroscopy, TEM with FIB and ELNES. Ni release was estimated using either ICPA or AAS. Potentiodynamic potential polarization of selected wires was performed in as-received state with no strain and in treated strained samples. Wire samples in the as-received state showed low breakdown potentials (200 mV); the improved corrosion resistance of these wires after treatment was not affected by strain. It is shown how processing techniques affect surface topography, chemistry and also Ni release. Nitinol wires with the thickest surface oxide TiO2 (up to 720 nm) showed the highest Ni release, attributed to the presence of particles of essentially pure Ni whose number and size increased while approaching the interface between the surface and the bulk. The biological implications of high and lasting Ni release are also discussed. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Guildford |
Editor |
|
Language |
|
Wos |
000262065500006 |
Publication Date |
2008-11-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0142-9612; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.402 |
Times cited |
102 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; G.0465.05 |
Approved |
Most recent IF: 8.402; 2009 IF: 7.365 |
Call Number |
UA @ lucian @ c:irua:72320 |
Serial |
1641 |
Permanent link to this record |
|
|
|
Author |
Srivastava, A.K.; Yang, Z.; Schryvers, D.; van Hurnbeeck, J. |
Title |
Effect of annealing on cold-rolled Ni-Ti alloys |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
Volume |
481 |
Issue |
Si |
Pages |
594-597 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000255716100123 |
Publication Date |
2007-06-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-5093; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.094 |
Times cited |
8 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; G0465.05 |
Approved |
Most recent IF: 3.094; 2008 IF: 1.806 |
Call Number |
UA @ lucian @ c:irua:69141 |
Serial |
797 |
Permanent link to this record |
|
|
|
Author |
Dobrynin, A.N.; Ievlev, D.N.; Hendrich, C.; Temst, K.; Lievens, P.; Hörmann, U.; Verbeeck, J.; Van Tendeloo, G.; Vantomme, A. |
Title |
Influence of finite size effects on exchange anisotropy in oxidized Co nanocluster assembled films |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
73 |
Issue |
24 |
Pages |
245416,1-8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We compare the magnetic properties of Co cluster assembled films with different degrees of oxidation. Clusters with grain size (2.3 +/- 0.7) nm are produced in a laser vaporization cluster source and soft-landed in ultrahigh vacuum conditions, forming highly porous nanogranular films. After exposure to air for different periods of time, the Co clusters oxidize and the sample may be considered as a thin antiferromagnetic Co oxide matrix containing ferromagnetic Co clusters. Magnetization measurements were performed in a temperature range from 300 down to 5 K, at applied magnetic fields up to 30 kOe. The exchange bias value at 5 K for the strongly oxidized sample is 4.8 kOe against the value of 0.75 kOe for the less oxidized sample. The mean values of the thicknesses of the Co oxide layers are estimated to be 0.6 and 0.3 nm for the more and less oxidized sample, respectively. We propose a method of measuring the exchange bias inducing temperature, i.e., the temperature at which exchange anisotropy is established. We determined the mean inducing temperatures for both samples, which are 55 and 25 K, respectively, for the more and less oxidized samples. Both temperatures are well below the bulk CoO Neel temperature of 292 K. A low value of the inducing temperature of the Co oxide layer is a consequence of its subnanometer thickness, while a large exchange bias value is a consequence of different dimensionality of Co clusters and Co oxide matrix. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000238696900114 |
Publication Date |
2006-06-16 |
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 |
17 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Gao; Iap; Hprn-Ct |
Approved |
Most recent IF: 3.836; 2006 IF: 3.107 |
Call Number |
UA @ lucian @ c:irua:59709UA @ admin @ c:irua:59709 |
Serial |
1622 |
Permanent link to this record |
|
|
|
Author |
Vernimmen, J.; Meynen, V.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P. |
Title |
Formation of a Ti-siliceous trimodal material with macroholes, mesopores and zeolitic features via a one-pot templating synthesis |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of porous materials |
Abbreviated Journal |
J Porous Mat |
Volume |
19 |
Issue |
2 |
Pages |
153-160 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Based on a facile one-pot templating synthesis, using a TS-1 zeolite recipe whereby part of the zeolite structure directing agent is replaced by a mesopore templating agent, a trimodal material is formed. The resulting meso-TSM material combines mesoporosity (Ti-MCM-41) with zeolitic features (TS-1) and a unique sheet-like morphology with uniform macroporous voids (macroholes). Moreover, the macrohole formation, mesoporosity and zeolitic properties of the meso-TSM material can be controlled in a straightforward way by adjusting the length of the hydrothermal treatment. This newly developed material may imply great potential for catalytic redox applications and diffusion limitated processes because of its highly tunable character in all three dimensions (micro-, meso- and macroporous scale). |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Kluwer Academic |
Place of Publication |
Boston, Mass. |
Editor |
|
Language |
|
Wos |
000301187600002 |
Publication Date |
2011-03-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1380-2224;1573-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.624 |
Times cited |
2 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Goa |
Approved |
Most recent IF: 1.624; 2012 IF: 1.348 |
Call Number |
UA @ lucian @ c:irua:88367 |
Serial |
1257 |
Permanent link to this record |
|
|
|
Author |
Bals, S.; Tirry, W.; Geurts, R.; Yang, Z.; Schryvers, D. |
Title |
High-quality sample preparation by low kV FIB thinning for analytical TEM measurements |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
13 |
Issue |
2 |
Pages |
80-86 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Focused ion beam specimen preparation has been used for NiTi samples and SrTiO(3)/SrRuO(3) multilayers with prevention of surface amorphization and Ga implantation by a 2-kV cleaning procedure. Transmission electron microscopy techniques show that the samples are of high quality with a controlled thickness over large scales. Furthermore, preferential thinning effects in multicompounds are avoided, which is important when analytical transmission electron microscopy measurements need to be interpreted in a quantitative manner. The results are compared to similar measurements acquired for samples obtained using conventional preparation techniques such as electropolishing for alloys and ion milling for oxides. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
Language |
|
Wos |
000245662200002 |
Publication Date |
2007-03-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
82 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Goa |
Approved |
Most recent IF: 1.891; 2007 IF: 1.941 |
Call Number |
UA @ lucian @ c:irua:65850 |
Serial |
1441 |
Permanent link to this record |
|
|
|
Author |
Liu, S.; Lebedev, O.I.; Mertens, M.; Meynen, V.; Cool, P.; Van Tendeloo, G.; Vansant, E.F. |
Title |
The merging of silica-surfactant microspheres under hydrothermal conditions |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
Volume |
116 |
Issue |
|
Pages |
141-146 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Post-synthesis hydrothermal treatments have been used to improve the quality of MCM-41 materials. In our latest work, merging of surfactant-containing silica microspheres during the hydrothermal treatments was observed. Mechanistic insights and the different stages that are involved in the merging process can be summarized as follows. First, the surfaces of the starting microspheres open up due to the dissolution of silica. Then the dissolved silica species provide mass source for the formation of particle necks connecting two neighboring microspheres. Gradually, surfaces of the starting microspheres are flattened to meet the needs of further growth of the necks. Finally, some chain-like highly-ordered mesoporous structures up to several micrometers are formed. The observed merging of the surfactant-containing microspheres is a re-assembling process, which is under the control of electrostatic force between the dissolved silica species and the surfactant cations. The occluded surfactant cations in the precursor spheres play important roles in the merging process. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000261133600021 |
Publication Date |
2008-04-13 |
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 ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Goa |
Approved |
Most recent IF: 3.615; 2008 IF: 2.555 |
Call Number |
UA @ lucian @ c:irua:72021 |
Serial |
1997 |
Permanent link to this record |
|
|
|
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 |
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 ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Goa |
Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
Call Number |
UA @ lucian @ c:irua:76032 |
Serial |
2503 |
Permanent link to this record |
|
|
|
Author |
Smeulders, G.; van Oers, C.; Van Havenbergh, K.; Houthoofd, K.; Mertens, M.; Martens, J.A.; Bals, S.; Maes, B.U.W.; Meynen, V.; Cool, P. |
Title |
Smart heating profiles for the synthesis of benzene bridged periodic mesoporous organosilicas |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
Volume |
175 |
Issue |
|
Pages |
585-591 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY) |
Abstract |
In this study the effects of the heating rate and heating time on the formation of crystal-like benzene bridged periodic mesoporous organosilicas (PMOs) are investigated. The time needed to heat up an autoclave during the hydrothermal treatment has shown to be crucial in the synthesis of PMOs, while the total duration of heating gave rise to only minor differences. By choosing a smart heating profile, superior PMO materials can be obtained in a short time. Different heating profiles in a range from one minute to one hour are adopted by microwave equipment and compared with conventional heating methods. The heating rate has a large influence on the porosity characteristics and the uniformity of the obtained particles. Moreover, two new alternative synthetic strategies to adopt the smart heating profile are presented, in order to give some possible solutions for the expensive microwave equipment. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000297875900069 |
Publication Date |
2011-10-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1385-8947; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.216 |
Times cited |
7 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Goa-Bof |
Approved |
Most recent IF: 6.216; 2011 IF: 3.461 |
Call Number |
UA @ lucian @ c:irua:93630 |
Serial |
3044 |
Permanent link to this record |
|
|
|
Author |
Dobrynin, A.N.; Ievlev, D.N.; Temst, K.; Lievens, P.; Margueritat, J.; Gonzalo, J.; Afonso, C.N.; Zhou, S.Q.; Vantomme, A.; Piscopiello, E.; Van Tendeloo, G. |
Title |
Critical size for exchange bias in ferromagnetic-antiferromagnetic particles |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
87 |
Issue |
1 |
Pages |
012501,1-3 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000230277900029 |
Publication Date |
2005-06-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
92 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; GOA/2004/02; IAP/P5/01; NanoCluster |
Approved |
Most recent IF: 3.411; 2005 IF: 4.127 |
Call Number |
UA @ lucian @ c:irua:59052 |
Serial |
545 |
Permanent link to this record |
|
|
|
Author |
Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B. |
Title |
The origin of p-type conductivity in ZnM2O4 (M = Co, Rh, Ir) spinels |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
16 |
Issue |
6 |
Pages |
2588-2596 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000329926700040 |
Publication Date |
2013-12-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
47 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Goa; Hercules |
Approved |
Most recent IF: 4.123; 2014 IF: 4.493 |
Call Number |
UA @ lucian @ c:irua:114829 |
Serial |
2525 |
Permanent link to this record |
|
|
|
Author |
di Vece, M.; Bals, S.; Lievens, P.; Van Tendeloo, G. |
Title |
Compositional changes of Pd-Au bimetallic nanoclusters upon hydrogenation |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
12 |
Pages |
125420,1-125420,4 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Changes in the size distribution and composition of bimetallic Pd-Au nanoclusters have been observed after hydrogen exposure. This effect is caused by hydrogen-induced Ostwald ripening whereby the hydrogen reduces the binding energy of the cluster atoms leading to their detachment from the cluster. The composition changes due to a difference in mobility of the detached palladium and gold atoms on the surface. Fast palladium atoms contribute to the formation of larger nanoclusters, while the slower gold atoms are confined to the smaller nanoclusters. These transformations in the Pd-Au nanocluster size and composition set a limit for chemical reactions in which such nanoclusters are involved together with hydrogen. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000270383300121 |
Publication Date |
2009-09-23 |
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 |
28 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Goa; Iap-Vi; Esteem 026019 |
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79232 |
Serial |
445 |
Permanent link to this record |
|
|
|
Author |
Meynen, V.; Cool, P.; Vansant, E.F.; Kortunov, P.; Grinberg, F.; Kärger, J.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G. |
Title |
Deposition of vanadium silicalite-1 nanoparticles on SBA-15 materials: structural and transport characteristics of SBA-VS-15 |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Microporous and mesoporous materials |
Abbreviated Journal |
Micropor Mesopor Mat |
Volume |
99 |
Issue |
1/2 |
Pages |
14-22 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000243845200003 |
Publication Date |
2006-10-28 |
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 |
23 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; GOA; Inside-Pores NoE (FP-EU) |
Approved |
Most recent IF: 3.615; 2007 IF: 2.210 |
Call Number |
UA @ lucian @ c:irua:61567 |
Serial |
647 |
Permanent link to this record |
|
|
|
Author |
Amini, M.N.; Leenaerts, O.; Partoens, B.; Lamoen, D. |
Title |
Graphane- and fluorographene-based quantum dots |
Type |
A1 Journal article |
Year |
2013 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
117 |
Issue |
31 |
Pages |
16242-16247 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
With the help of first-principles calculations, we investigate graphane/fluorographene heterostructures with special attention for graphane and fluorographene-based quantum dots. Graphane and fluorographene have large electronic band gaps, and we show that their band structures exhibit a strong type-II alignment. In this way, it is possible to obtain confined electron states in fluorographene nanostructures by embedding them in a graphane crystal. Bound hole states can be created in graphane domains embedded in a fluorographene environment. For circular graphane/fluorographene quantum dots, localized states can be observed in the band gap if the size of the radii is larger than approximately 4 to 5 Å. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000323082300046 |
Publication Date |
2013-07-15 |
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 |
14 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; GOW; Hercules |
Approved |
Most recent IF: 4.536; 2013 IF: 4.835 |
Call Number |
UA @ lucian @ c:irua:109457 |
Serial |
1367 |
Permanent link to this record |
|
|
|
Author |
Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D. |
Title |
Homologous series of layered structures in binary and ternary Bi-Sb-Te-Se systems : ab initio study |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
89 |
Issue |
5 |
Pages |
054106-54109 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
In order to account explicitly for the existence of long-periodic layered structures and the strong structural relaxations in the most common binary and ternary alloys of the Bi-Sb-Te-Se system, we have developed a one-dimensional cluster expansion (CE) based on first-principles electronic structure calculations, which accounts for the Bi and Sb bilayer formation. Excellent interlayer distances are obtained with a van der Waals density functional. It is shown that a CE solely based on pair interactions is sufficient to provide an accurate description of the ground-state energies of Bi-Sb-Te-Se binary and ternary systems without making the data set of ab initio calculated structures unreasonably large. For the binary alloys A1−xQx (A=Sb, Bi; Q=Te, Se), a ternary CE yields an almost continuous series of (meta)stable structures consisting of consecutive A bilayers next to consecutive A2Q3 for 0<x<0.6. For x>0.6, the binary alloy segregates into pure Q and A2Q3. The Bi-Sb system is described by a quaternary CE and is found to be an ideal solid solution stabilized by entropic effects at T≠0 K but with an ordered structure of alternating Bi and Sb layers for x=0.5 at T=0 K. A quintuple CE is used for the ternary Bi-Sb-Te system, where stable ternary layered compounds with an arbitrary stacking of Sb2Te3, Bi2Te3, and Te-Bi-Te-Sb-Te quintuple units are found, optionally separated by mixed Bi/Sb bilayers. Electronic properties of the stable compounds were studied taking spin-orbit coupling into account. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000332420900001 |
Publication Date |
2014-03-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
5 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Hercules |
Approved |
Most recent IF: 3.836; 2014 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:114910 |
Serial |
1487 |
Permanent link to this record |
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Author |
Leus, K.; Concepcion, P.; Vandichel, M.; Meledina, M.; Grirrane, A.; Esquivel, D.; Turner, S.; Poelman, D.; Waroquier, M.; Van Speybroeck, V.; Van Tendeloo, G.; García, H.; Van Der Voort, P.; |
Title |
Au@UiO-66 : a base free oxidation catalyst |
Type |
A1 Journal article |
Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
Volume |
5 |
Issue |
5 |
Pages |
22334-22342 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We present the in situ synthesis of Au nanoparticles within the Zr based Metal Organic Framework, UiO-66. The resulting Au@UiO-66 materials were characterized by means of N-2 sorption, XRPD, UV-Vis, XRF, XPS and TEM analysis. The Au nanoparticles (NP) are homogeneously distributed along the UiO-66 host matrix when using NaBH4 or H-2 as reducing agents. The Au@UiO-66 materials were evaluated as catalysts in the oxidation of benzyl alcohol and benzyl amine employing O-2 as oxidant. The Au@MOF materials exhibit a very high selectivity towards the ketone (up to 100%). Regenerability and stability tests demonstrate that the Au@UiO-66 catalyst can be recycled with a negligible loss of Au species and no loss of crystallinity. In situ IR measurements of UiO-66 and Au@UiO-66-NaBH4, before and after treatment with alcohol, showed an increase in IR bands that can be assigned to a combination of physisorbed and chemisorbed alcohol species. This was confirmed by velocity power spectra obtained from the molecular dynamics simulations. Active peroxo and oxo species on Au could be visualized with Raman analysis. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000350643700005 |
Publication Date |
2015-02-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2046-2069; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.108 |
Times cited |
38 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; Hercules; 246791 COUNTATOMS; IAP-PAI |
Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
Call Number |
c:irua:125431 |
Serial |
207 |
Permanent link to this record |
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Author |
Schouteden, K.; Zeng, Y.-J.; Lauwaet, K.; Romero, C.P.; Goris, B.; Bals, S.; Van Tendeloo, G.; Lievens, P.; Van Haesendonck, C. |
Title |
Band structure quantization in nanometer sized ZnO clusters |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
5 |
Issue |
9 |
Pages |
3757-3763 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Nanometer sized ZnO clusters are produced in the gas phase and subsequently deposited on clean Au(111) surfaces under ultra-high vacuum conditions. The zinc blende atomic structure of the approximately spherical ZnO clusters is resolved by high resolution scanning transmission electron microscopy. The large band gap and weak n-type conductivity of individual clusters are determined by scanning tunnelling microscopy and spectroscopy at cryogenic temperatures. The conduction band is found to exhibit clear quantization into discrete energy levels, which can be related to finite-size effects reflecting the zero-dimensional confinement. Our findings illustrate that gas phase cluster production may provide unique possibilities for the controlled fabrication of high purity quantum dots and heterostructures that can be size selected prior to deposition on the desired substrate under controlled ultra-high vacuum conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000317859400026 |
Publication Date |
2013-03-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
13 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; Hercules; COUNTATOMS |
Approved |
Most recent IF: 7.367; 2013 IF: 6.739 |
Call Number |
UA @ lucian @ c:irua:108518 |
Serial |
219 |
Permanent link to this record |
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Author |
Turner, S.; Lebedev, O.I.; Verbeeck, J.; Gehrke, K.; Moshnyaga, V.; Van Tendeloo, G. |
Title |
Structural phase transition and spontaneous interface reconstruction in La2/3Ca1/3MnO3/BaTiO3 superlattices |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
3 |
Pages |
035418-8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
(La2/3Ca1/3MnO3)n/(BaTiO3)m (LCMOn/BTOm) superlattices on MgO and SrTiO3 substrates with different layer thicknesses (n = 10, 38, 40 and m = 5, 18, 20) have been grown by metal organic aerosol deposition (MAD) and have been fully characterized down to the atomic scale to study the interface characteristics. Scanning transmission electron microscopy combined with spatially resolved electron energy-loss spectroscopy provides clear evidence for the existence of atomically sharp interfaces in MAD grown films, which exhibit epitaxial growth conditions, a uniform normal strain, and a fully oxidized state. Below a critical layer thickness the LCMO structure is found to change from the bulk Pnma symmetry to a pseudocubic R3̅ c symmetry. An atomically flat interface reconstruction consisting of a single Ca-rich atomic layer is observed on the compressively strained BTO on LCMO interface, which is thought to partially neutralize the total charge from the alternating polar atomic layers in LCMO as well as relieving strain at the interface. No interface reconstruction is observed at the tensile strained LCMO on BTO interface. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000313940400008 |
Publication Date |
2013-01-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; Hercules; Countatoms |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:106180 |
Serial |
3245 |
Permanent link to this record |
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Author |
Wang, A.; Turner, S.; Van Aert, S.; van Dyck, D. |
Title |
An alternative approach to determine attainable resolution directly from HREM images |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
133 |
Issue |
|
Pages |
50-61 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
The concept of resolution in high-resolution electron microscopy (HREM) is the power to resolve neighboring atoms. Since the resolution is related to the width of the point spread function of the microscope, it could in principle be determined from the image of a point object. However, in electron microscopy there are no ideal point objects. The smallest object is an individual atom. If the width of an atom is much smaller than the resolution of the microscope, this atom can still be considered as a point object. As the resolution of the microscope enters the sub-Å regime, information about the microscope is strongly entangled with the information about the atoms in HREM images. Therefore, we need to find an alternative method to determine the resolution in an object-independent way. In this work we propose to use the image wave of a crystalline object in zone axis orientation. Under this condition, the atoms of a column act as small lenses so that the electron beam channels through the atom column periodically. Because of this focusing, the image wave of the column can be much more peaked than the constituting atoms and can thus be a much more sensitive probe to measure the resolution. Our approach is to use the peakiness of the image wave of the atom column to determine the resolution. We will show that the resolution can be directly linked to the total curvature of the atom column wave. Moreover, we can then directly obtain the resolution of the microscope given that the contribution from the object is known, which is related to the bounding energy of the atom. The method is applied on an experimental CaTiO3 image wave. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000324471800007 |
Publication Date |
2013-05-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
2.843 |
Times cited |
|
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
FWO; Hercules; Esteem2; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:109919 |
Serial |
90 |
Permanent link to this record |
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Author |
Martens, J.A.; Thybaut, J.W.; Denayer, J.F.M.; Sree, S.P.; Aerts, A.; Reyniers, M.-F.; van Speybroeck, V.; Waroquier, M.; Buekenhoudt, A.; Vankelecom, I.; Buijs, W.; Persoons, J.; Baron, G.V.; Bals, S.; Van Tendeloo, G.; Marin, G.B.; Jacobs, P.A.; Kirschhock, C.E.A. |
Title |
Catalytic and molecular separation properties of Zeogrids and Zeotiles |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Catalysis today |
Abbreviated Journal |
Catal Today |
Volume |
168 |
Issue |
1 |
Pages |
17-27 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Zeogrids and Zeotiles are hierarchical materials built from assembled MFI zeolite precursor units. Permanent secondary porosity in these materials is obtained through self assembly of nanoparticles encountered in MFI zeolite synthesis in the presence of supramolecular templates. Hereon, the aggregated species are termed nanoslabs. Zeogrids are layered materials with lateral spacings between nanoslabs creating galleries qualifying as supermicropores. Zeotiles present a diversity of tridimensional nanoslab assemblies with mesopores. Zeotile-1, -4 and -6 are hexagonal mesostructures. Zeotile-1 has triangular and hexagonal channels; Zeotile-4 has hexagonal channels interconnected via slits. Zeotile-2 has a cubic structure with gyroid type mesoporosity. The behavior of Zeogrids and Zeotiles in adsorption, membrane and chromatographic separation and catalysis has been characterized and compared with zeolites and mesoporous materials derived from unstructured silica sources. Shape selectivity was detected via adsorption of n- and iso-alkanes. The mesoporosity of Zeotiles can be exploited in chromatographic separation of biomolecules. Zeotiles present attractive separation properties relevant to CO2 sequestration. Because of its facile synthesis procedure without hydrothermal steps Zeogrid is convenient for membrane synthesis. The performance of Zeogrid membrane in gas separation, nanofiltration and pervaporation is reported. In the Beckmann rearrangement of cyclohexanone oxime Zeogrids and Zeotiles display a catalytic activity characteristic of silicalite-1 zeolites. Introduction of acidity and redox catalytic activity can be achieved via incorporation of Al and Ti atoms in the nanoslabs during synthesis. Zeogrids are active in hydrocracking, catalytic cracking, alkylation and epoxidation reactions. Zeogrids and Zeotiles often behave differently from ordered mesoporous materials as well as from zeolites and present a valuable extension of the family of hierarchical silicate based materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000291033300003 |
Publication Date |
2011-03-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0920-5861; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.636 |
Times cited |
13 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
Fwo; Iap
Sbo |
Approved |
Most recent IF: 4.636; 2011 IF: 3.407 |
Call Number |
UA @ lucian @ c:irua:88647 |
Serial |
290 |
Permanent link to this record |