Records |
Author |
Khazzan, S.; Bessais, L.; Van Tendeloo, G.; Mliki, N. |
Title |
Correlation between the nanocrystalline Sm(Fe,Mo)12 and its out of equilibrium phase Sm(Fe,Mo)10 |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of magnetism and magnetic materials |
Abbreviated Journal |
J Magn Magn Mater |
Volume |
363 |
Issue |
|
Pages |
125-132 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Nanostructured Sm-Fe-Mo semi-hard magnetic material exhibiting enhanced magnetic properties can be produced by ball milling followed by recrystallization. Milled samples were annealed for 30 min in a vacuum at different temperatures (T-A) between 700 and 1190 degrees C. The effects of heat treatment and Mo content on structural and magnetic property changes have been investigated by means of X-ray diffraction using the Rietvekl method, transmission electron microscopy and magnetic measurements. For samples annealed at T-A > 900 degrees C the tetragonal ThMn12-type structure is identified, while for 700 < T-A < 900 degrees C a new out of equilibrium P6/mmm type structure was found as the major phase. This novel nanocrystalline phase has never been synthesized before. The correspondent stoichiometry is determined on the basis of the vacancy model. The Rietveld analysis gives a stoichiometry ratio equal to 1:10, for the out of equilibrium hexagonal phase, which is described with three crystallographic transition metal sites: 3g is fully occupied, 61 occupation is limited to hexagons surrounding the Fe dumbbell pairs 2e. We have performed a magnetic and structural study of nanocrystalline metastable P6/mrnm Sm(Fe1-xMo)(10), correlated with structural transformation towards its equilibrium derivative 14/mrnm Sm(Fe1-xMo)(12). A maximum of the coercive field H-C (H-C > 5 kOe) has been observed for the new hexagonal P6/rnmm phase suggesting that nanocrystalline Sm(Fe,Mo)(10), is a semi hard material, and is potential candidate for magnetic recording. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000335393900021 |
Publication Date |
2014-04-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-8853; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.63 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.63; 2014 IF: 1.970 |
Call Number |
UA @ lucian @ c:irua:117139 |
Serial |
524 |
Permanent link to this record |
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|
|
Author |
Niermann, T.; Verbeeck, J.; Lehmann, M. |
Title |
Creating arrays of electron vortices |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
136 |
Issue |
|
Pages |
165-170 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We demonstrate the production of an ordered array of electron vortices making use of an electron optical setup consisting of two electrostatic biprisms. The biprism filaments are oriented nearly orthogonal with respect to each other in a transmission electron microscope. Matching the position of the filaments, we can choose to form different topological features in the electron wave. We outline the working principle of the setup and demonstrate fist experimental results. This setup partially bridges the gap between angular momentum carried by electron spin, which is intrinsic and therefore present in any position of the wave, and angular momentum carried by the vortex character of the wave, which can be extrinsic depending on the axis around which it is measured. (C) 2013 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000327884700021 |
Publication Date |
2013-10-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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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 |
9 |
Open Access |
|
Notes |
FP7; Countatoms; Vortex ECASJO_; |
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
Call Number |
UA @ lucian @ c:irua:112837UA @ admin @ c:irua:112837 |
Serial |
538 |
Permanent link to this record |
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Author |
Boulay, E.; Nakano, J.; Turner, S.; Idrissi, H.; Schryvers, D.; Godet, S. |
Title |
Critical assessments and thermodynamic modeling of BaO-SiO2 and SiO2-TiO2 systems and their extensions into liquid immiscibility in the BaO-SiO2-TiO2 system |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Calphad computer coupling of phase diagrams and thermochemistry |
Abbreviated Journal |
Calphad |
Volume |
47 |
Issue |
|
Pages |
68-82 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This study discusses rational reproduction of liquid immiscibility in the BaO-SiO2-TiO2 system. While a ternary assessment requires sub-binary descriptions in the same thermodynamic model, the related sub-binary systems BaO-SiO2, BaO-TiO2 and SiO2-TiO2 liquid and solid phases have been evaluated using different thermodynamic models in the literature. In this study, BaO-SiO2 and SiO2-TiO2 were assessed using the Ionic Two Sublattice model (I2SL) based on experimental data from the literature. BaO-TiO2 was already assessed using this model. Binary descriptions developed were then used for the assessment of liquid immiscibility in the BaO-SiO2-TiO2 system. Ternary interaction parameters were found necessary for rational reproduction of the new ternary experimental data gathered in the present work. The model parameters for each system were evaluated using a CAPLHAD approach. A set of parameters is proposed. They show good agreement between the calculated and experimental equilibrium liquidus, liquid immiscibility and thermochemical properties in the BaO-SiO2-TiO2 system. (C) 2014 Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000346224700008 |
Publication Date |
2014-07-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0364-5916; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.6 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.6; 2014 IF: 1.370 |
Call Number |
UA @ lucian @ c:irua:122776 |
Serial |
540 |
Permanent link to this record |
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|
|
Author |
Morozov, V.A.; Raskina, M.V.; Lazoryak, B.I.; Meert, K.W.; Korthout, K.; Smet, P.F.; Poelman, D.; Gauquelin, N.; Verbeeck, J.; Abakumov, A.M.; Hadermann, J.; |
Title |
Crystal Structure and Luminescent Properties of R2-xEux(MoO4)(3) (R = Gd, Sm) Red Phosphors |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
26 |
Issue |
24 |
Pages |
7124-7136 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The R-2(MoO4)(3) (R = rare earth elements) molybdates doped with Eu3+ cations are interesting red-emitting materials for display and solid-state lighting applications. The structure and luminescent properties of the R2-xEux(MoO4)(3) (R = Gd, Sm) solid solutions have been investigated as a function of chemical composition and preparation conditions. Monoclinic (alpha) and orthorhombic (beta') R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) modifications were prepared by solid-state reaction, and their structures were investigated using synchrotron powder X-ray diffraction and transmission electron microscopy. The pure orthorhombic beta'-phases could be synthesized only by quenching from high temperature to room temperature for Gd2-xEux(MoO4)(3) in the Eu3+-rich part (x > 1) and for all Sm2-xEux(MoO4)(3) solid solutions. The transformation from the alpha-phase to the beta'-phase results in a notable increase (similar to 24%) of the unit cell volume for all R2-xEux(MoO4)(3) (R = Sm, Gd) solid solutions. The luminescent properties of all R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) solid solutions were measured, and their optical properties were related to their structural properties. All R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) phosphors emit intense red light dominated by the D-5(0)-> F-7(2) transition at similar to 616 nm. However, a change in the multiplet splitting is observed when switching from the monoclinic to the orthorhombic structure, as a consequence of the change in coordination polyhedron of the luminescent ion from RO8 to RO7 for the alpha- and beta'-modification, respectively. The Gd2-xEux(MoO4)(3) solid solutions are the most efficient emitters in the range of 0 < x < 1.5, but their emission intensity is comparable to or even significantly lower than that of Sm2-xEux(MoO4)(3) for higher Eu3+ concentrations (1.5 <= x <= 1.75). Electron energy loss spectroscopy (EELS) measurements revealed the influence of the structure and element content on the number and positions of bands in the ultraviolet-visible-infrared regions of the EELS spectrum. |
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 |
000347139700027 |
Publication Date |
2014-11-27 |
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 |
24 |
Open Access |
|
Notes |
Fwo G039211n; G004413n; 278510 Vortex ECASJO_; |
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
Call Number |
UA @ lucian @ c:irua:122829UA @ admin @ c:irua:122829 |
Serial |
558 |
Permanent link to this record |
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|
|
Author |
Gorlé, C.; Larsson, J.; Emory, M.; Iaccarino, G. |
Title |
The deviation from parallel shear flow as an indicator of linear eddy-viscosity model inaccuracy |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physics of fluids |
Abbreviated Journal |
Phys Fluids |
Volume |
26 |
Issue |
5 |
Pages |
051702 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A marker function designed to indicate in which regions of a generic flow field the results from linear eddy-viscosity turbulence models are plausibly inaccurate is introduced. The marker is defined to identify regions that deviate from parallel shear flow. For two different flow fields it is shown that these regions largely coincide with regions where the prediction of the Reynolds stress divergence is inaccurate. The marker therefore offers a guideline for interpreting results obtained from Reynolds-averaged Navier-Stokes simulations and provides a basis for the further development of turbulence model-form uncertainty quantification methods. (C) 2014 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Woodbury, N.Y. |
Editor |
|
Language |
|
Wos |
000337103900002 |
Publication Date |
2014-05-15 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1070-6631;1089-7666; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.232 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.232; 2014 IF: 2.031 |
Call Number |
UA @ lucian @ c:irua:118385 |
Serial |
684 |
Permanent link to this record |
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|
|
Author |
Samal, D.; Tan, H.; Takamura, Y.; Siemons, W.; Verbeeck, J.; Van Tendeloo, G.; Arenholz, E.; Jenkins, C.A.; Rijnders, G.; Koster, G. |
Title |
Direct structural and spectroscopic investigation of ultrathin films of tetragonal CuO: Six-fold coordinated copper |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
Volume |
105 |
Issue |
1 |
Pages |
17003-17005 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Unlike other 3d transition metal monoxides (MnO, FeO, CoO, and NiO), CuO is found in a low-symmetry distorted monoclinic structure rather than the rocksalt structure. We report here of the growth of ultrathin CuO films on SrTiO3 substrates; scanning transmission electron microscopy was used to show the stabilization of a tetragonal rocksalt structure with an elongated c-axis such that c/a similar to 1.34 and the Cu-O-Cu bond angle similar to 180 degrees, pointing to metastable six-fold coordinated Cu. X-ray absorption spectroscopy demonstrates that the hole at the Cu site for the CuO is localized in 3d(x2-y2) orbital unlike the well-studied monoclinic CuO phase. The experimental confirmation of the tetragonal structure of CuO opens up new avenues to explore electronic and magnetic properties of six-fold coordinated Cu. Copyright (C) EPLA, 2014 |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Paris |
Editor |
|
Language |
|
Wos |
000331197100015 |
Publication Date |
2014-01-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.957 |
Times cited |
15 |
Open Access |
|
Notes |
This work was carried out with financial support from the AFOSR and EOARD projects (project No.: FA8655-10-1-3077) and also supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No. 246791 – COUNTATOMS, ERC Starting Grant 278510 VORTEX, Grant No. NMP3-LA-2010-246102 IFOX and an Integrated Infrastructure Initiative, reference No. 312483-ESTEEM2. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. Advanced Light Source is supported by the Office of Science, Office of Basic Energy Sciences of the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231. YT acknowledges support from the National Science Foundation (DMR-0747896). WS was supported by the US DOE, Basic Energy Sciences, Materials Sciences and Engineering Division. ECASJO_; |
Approved |
Most recent IF: 1.957; 2014 IF: 2.095 |
Call Number |
UA @ lucian @ c:irua:115806UA @ admin @ c:irua:115806 |
Serial |
722 |
Permanent link to this record |
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|
|
Author |
Lubk, A.; Javon, E.; Cherkashin, N.; Reboh, S.; Gatel, C.; Hytch, M. |
Title |
Dynamic scattering theory for dark-field electron holography of 3D strain fields |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
136 |
Issue |
|
Pages |
42-49 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Dark-held electron holography maps strain in crystal lattices into reconstructed phases over large fields of view. Here we investigate the details of the lattice strain-reconstructed phase relationship by applying dynamic scattering theory both analytically and numerically. We develop efficient analytic linear projection rules for 3D strain fields, facilitating a straight-forward calculation of reconstructed phases from 3D strained materials. They are used in the following to quantify the influence of various experimental parameters like strain magnitude, specimen thickness, excitation error and surface relaxation. (C) 2013 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000327884700006 |
Publication Date |
2013-07-29 |
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 |
European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference312483 – ESTEEM2); esteem2_jra4 |
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
Call Number |
UA @ lucian @ c:irua:112836 |
Serial |
766 |
Permanent link to this record |
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|
|
Author |
Javon, E.; Lubk; Cours, R.; Reboh, S.; Cherkashin, N.; Houdellier, F.; Gatel, C.; Hytch, M.J. |
Title |
Dynamical effects in strain measurements by dark-field electron holography |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
147 |
Issue |
|
Pages |
70-85 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Here, we study the effect of dynamic scattering on the projected geometric phase and strain maps reconstructed using dark-field electron holography (DFEH) for non-uniformly strained crystals. The investigated structure consists of a {SiGe/Si} superlattice grown on a (001)-Si substrate. The three dimensional strain held within the thin TEM lamella is modelled by the finite element method. The observed projected strain is simulated in two ways by multiplying the strain at each depth in the crystal by a weighting function determined from a recently developed analytical two-beam dynamical theory, and by simply taking the average value. We demonstrate that the experimental results need to be understood in terms of the dynamical theory and good agreement is found between the experimental and simulated results. Discrepancies do remain for certain cases and are likely to be from an imprecision in the actual two-beam diffraction conditions, notably the deviation parameter, and points to limitations in the 2-beam approximation. Finally, a route towards a 3D reconstruction of strain fields is proposed. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000343157400009 |
Publication Date |
2014-07-02 |
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 |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
Call Number |
UA @ lucian @ c:irua:121108 |
Serial |
769 |
Permanent link to this record |
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|
Author |
E. Zaghi, A.; Buffière, M.; Koo, J.; Brammertz, G.; Batuk, M.; Verbist, C.; Hadermann, J.; Kim, W.K.; Meuris, M.; Poortmans, J.; Vleugels, J.; |
Title |
Effect of selenium content of CuInSex alloy nanopowder precursors on recrystallization of printed CuInSe2 absorber layers during selenization heat treatment |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
|
Issue |
|
Pages |
1-7 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Polycrystalline CuInSe2 semiconductors are efficient light absorber materials for thin film solar cell technology, whereas printing is one of the promising low cost and non-vacuum approaches for the fabrication of thin film solar cells. The printed precursors are transformed into a dense polycrystalline CuInSe2 semiconductor film via thermal treatment in ambient selenium atmosphere (selenization). In this study, the effect of the selenium content in high purity mechanically synthesized CuInSex (x = 2, 1.5, 1 or 0.5) alloy precursors on the recrystallization of the CuInSe2 phase during the selenization process was investigated. The nanostructure and phase variation of CuInSex nanopowders were investigated by different characterization techniques. The recrystallization process of the 12 μm thick CuInSex coatings into the CuInSe2 phase during selenization in selenium vapor was investigated via in-situ high temperature X-ray diffraction. The CuInSex precursors with lower selenium content showed a more pronounced phase conversion into CuInSe2 compared to the higher selenium content CuInSex precursors. Moreover, the CuInSex (x = 0.5 and 1) precursor resulted in a denser polycrystalline CuInSe2 semiconductor film with larger crystals. This could be attributed to a more intensive atomic interdiffusion within the CuInSex precursor system compared to a CuInSe2 phase precursor, and the formation of intermediate CuSe and CuSe2 fluxing phases during selenization. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000352225900004 |
Publication Date |
2014-10-13 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.879; 2014 IF: 1.759 |
Call Number |
c:irua:121330 |
Serial |
834 |
Permanent link to this record |
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|
|
Author |
Meert, K.W.; Morozov, V.A.; Abakumov, A.M.; Hadermann, J.; Poelman, D.; Smet, P.F. |
Title |
Energy transfer in Eu3+ doped scheelites : use as thermographic phosphor |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Optics express |
Abbreviated Journal |
Opt Express |
Volume |
22 |
Issue |
9 |
Pages |
A961-A972 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In this paper the luminescence of the scheelite-based CaGd2(1-x)Eu2x(WO4)4 solid solutions is investigated as a function of the Eu content and temperature. All phosphors show intense red luminescence due to the 5D0 7F2 transition in Eu3+, along with other transitions from the 5D1 and 5D0 excited states. For high Eu3+ concentrations the intensity ratio of the emission originating from the 5D1 and 5D0 levels has a non-conventional temperature dependence, which could be explained by a phonon-assisted cross-relaxation process. It is demonstrated that this intensity ratio can be used as a measure of temperature with high spatial resolution, allowing the use of these scheelites as thermographic phosphor. The main disadvantage of many thermographic phosphors, a decreasing signal for increasing temperature, is absent. |
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 |
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Language |
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Wos |
000335905300037 |
Publication Date |
2014-04-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1094-4087; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.307 |
Times cited |
47 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.307; 2014 IF: 3.488 |
Call Number |
UA @ lucian @ c:irua:117067 |
Serial |
1044 |
Permanent link to this record |
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|
|
Author |
Alaria, J.; Borisov, P.; Dyer, M.S.; Manning, T.D.; Lepadatu, S.; Cain, M.G.; Mishina, E.D.; Sherstyuk, N.E.; Ilyin, N.A.; Hadermann, J.; Lederman, D.; Claridge, J.B.; Rosseinsky, M.J.; |
Title |
Engineered spatial inversion symmetry breaking in an oxide heterostructure built from isosymmetric room-temperature magnetically ordered components |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
Volume |
5 |
Issue |
4 |
Pages |
1599-1610 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Royal Society of Chemistry |
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000332467400044 |
Publication Date |
2014-01-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-6520;2041-6539; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.668 |
Times cited |
24 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.668; 2014 IF: 9.211 |
Call Number |
UA @ lucian @ c:irua:117064 |
Serial |
1045 |
Permanent link to this record |
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|
|
Author |
Carraro, G.; Maccato, C.; Gasparotto, A.; Montini, T.; Turner, S.; Lebedev, O.I.; Gombac, V.; Adami, G.; Van Tendeloo, G.; Barreca, D.; Fornasiero, P.; |
Title |
Enhanced hydrogen production by photoreforming of renewable oxygenates through nanostructured Fe2O3 polymorphs |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
24 |
Issue |
3 |
Pages |
372-378 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Sunlight-driven hydrogen production via photoreforming of aqueous solutions containing renewable compounds is an attractive option for sustainable energy generation with reduced carbon footprint. Nevertheless, the absence of photocatalysts combining high efficiency and stability upon solar light activation has up to date strongly hindered the development of this technology. Herein, two scarcely investigated iron(III) oxide polymorphs, β- and ε-Fe2O3, possessing a remarkable activity in sunlight-activated H2 generation from aqueous solutions of renewable oxygenates (i.e., ethanol, glycerol, glucose) are reported. For β-Fe2O3 and ε-Fe2O3, H2 production rates up to 225 and 125 mmol h−1 m−2 are obtained, with significantly superior performances with respect to the commonly investigated α-Fe2O3. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000332832500011 |
Publication Date |
2013-10-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1616-301X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
95 |
Open Access |
|
Notes |
Countatoms; Hercules; Fwo |
Approved |
Most recent IF: 12.124; 2014 IF: 11.805 |
Call Number |
UA @ lucian @ c:irua:113090 |
Serial |
1051 |
Permanent link to this record |
|
|
|
Author |
Zhou, C.; Ji, G.; Chen, Z.; Wang, M.; Addad, A.; Schryvers, D.; Wang, H. |
Title |
Fabrication, interface characterization and modeling of oriented graphite flakes/Si/Al composites for thermal management applications |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Materials and design |
Abbreviated Journal |
Mater Design |
Volume |
63 |
Issue |
|
Pages |
719-728 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Highly thermally conductive graphite flakes (Gf)/Si/Al composites have been fabricated using Gf, Si powder and an AlSi7Mg0.3 alloy by an optimized pressure infiltration process for thermal management applications. In the composites, the layers of Gf were spaced apart by Si particles and oriented perpendicular to the pressing direction, which offered the opportunity to tailor the thermal conductivity (TC) and coefficient of thermal expansion (CTE) of the composites. Microstructural characterization revealed that the formation of a clean and tightly-adhered interface at the nanoscale between the side surface of the Gf and Al matrix, devoid of a detrimental Al4C3 phase and a reacted amorphous AlSiOC layer, contributed to excellent thermal performance along the alignment direction. With increasing volume fraction of Gf from 13.7 to 71.1 vol.%, the longitudinal (i.e. parallel to the graphite layers) TC of the composites increased from 179 to 526 W/m K, while the longitudinal CTE decreased from 12.1 to 7.3 ppm/K (matching the values of electronic components). Furthermore, the modified layers-in-parallel model better fitted the longitudinal TC data than the layers-in-parallel model and confirmed that the clean and tightly-adhered interface is favorable for the enhanced longitudinal TC. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Reigate |
Editor |
|
Language |
|
Wos |
000340949300086 |
Publication Date |
2014-07-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0261-3069; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
61 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:118124 |
Serial |
1166 |
Permanent link to this record |
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|
|
Author |
Zaikina, J.V.; Batuk, M.; Abakumov, A.M.; Navrotsky, A.; Kauziarich, S.M. |
Title |
Facile synthesis of Ba1-xKxFe2As2 superconductors via hydride route |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
136 |
Issue |
48 |
Pages |
16932-16939 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have developed a fast, easy, and scalable synthesis method for Ba1xKxFe2As2 (0 ≤ x ≤ 1) superconductors using hydrides BaH2 and KH as a source of barium and potassium metals. Synthesis from hydrides provides better mixing and easier handling of the starting materials, consequently leading to faster reactions and/or lower synthesis temperatures. The reducing atmosphere provided by the evolved hydrogen facilitates preparation of oxygen-free powders. By a combination of methods we have shown that Ba1xKxFe2As2 obtained via hydride route has the same characteristics as when it is prepared by traditional solid-state synthesis. Refinement from synchrotron powder X-ray diffraction data confirms a linear dependence of unit cell parameters upon K content as well as the tetragonal to orthorhombic transition at low temperatures for compositions with x < 0.2. Magnetic measurements revealed dome-like dependence of superconducting transition temperature Tc upon K content with a maximum of 38 K for x close to 0.4. Electron diffraction and high-resolution high-angle annular dark-field scanning transmission electron microscopy indicates an absence of Ba/K ordering, while local inhomogeneity in the Ba/K distribution takes place at a scale of several angstroms along [110] crystallographic direction. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000345883900040 |
Publication Date |
2014-11-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
13 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 13.858; 2014 IF: 12.113 |
Call Number |
UA @ lucian @ c:irua:121331 |
Serial |
1169 |
Permanent link to this record |
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|
|
Author |
Damm, H.; Adriaensens, P.; De Dobbelaere, C.; Capon, B.; Elen, K.; Drijkoningen, J.; Conings, B.; Manca, J.V.; D’Haen, J.; Detavernier, C.; Magusin, P.C.M.M.; Hadermann, J.; Hardy, A.; Van Bael, M.K.; |
Title |
Factors Influencing the Conductivity of Aqueous Sol(ution)-Gel-Processed Al-Doped ZnO Films |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
26 |
Issue |
20 |
Pages |
5839-5851 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000343950300004 |
Publication Date |
2014-10-06 |
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 |
24 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
Call Number |
UA @ lucian @ c:irua:121211 |
Serial |
1170 |
Permanent link to this record |
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|
|
Author |
Rehor, I.; Mackova, H.; Filippov, S.K.; Kucka, J.; Proks, V.; Slegerova, J.; Turner, S.; Van Tendeloo, G.; Ledvina, M.; Hruby, M.; Cigler, P.; |
Title |
Fluorescent nanodiamonds with bioorthogonally reactive protein-resistant polymeric coatings |
Type |
A1 Journal article |
Year |
2014 |
Publication |
ChemPlusChem |
Abbreviated Journal |
Chempluschem |
Volume |
79 |
Issue |
1 |
Pages |
21-24 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The novel synthesis of a polymeric interface grown from the surface of bright fluorescent nanodiamonds is reported. The polymer enables bioorthogonal attachment of various molecules by click chemistry; the particles are resistant to nonspecific protein adsorption and show outstanding colloidal stability in buffers and biological media. The coating fully preserves the unique optical properties of the nitrogen-vacancy centers that are crucial for bioimaging and sensoric applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
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Language |
|
Wos |
000337974900002 |
Publication Date |
2013-12-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2192-6506; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.797 |
Times cited |
34 |
Open Access |
|
Notes |
EU 7FP Program (no.262348); European Soft Matter Infrastructure; ESMI; ERC (grant no.246791)-COUNTATOMS; FWO |
Approved |
Most recent IF: 2.797; 2014 IF: 2.997 |
Call Number |
UA @ lucian @ c:irua:113088 |
Serial |
1235 |
Permanent link to this record |
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|
|
Author |
Kundu, P.; Heidari, H.; Bals, S.; Ravishankar, N.; Van Tendeloo, G. |
Title |
Formation and thermal stability of gold-silica nanohybrids : insight into the mechanism and morphology by electron tomography |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
53 |
Issue |
15 |
Pages |
3970-3974 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Gold-silica hybrids are appealing in different fields of applications like catalysis, sensorics, drug delivery, and biotechnology. In most cases, the morphology and distribution of the heterounits play significant roles in their functional behavior. Methods of synthesizing these hybrids, with variable ordering of the heterounits, are replete; however, a complete characterization in three dimensions could not be achieved yet. A simple route to the synthesis of Au-decorated SiO2 spheres is demonstrated and a study on the 3D ordering of the heterounits by scanning transmission electron microscopy (STEM) tomography is presentedat the final stage, intermediate stages of formation, and after heating the hybrid. The final hybrid evolves from a soft self-assembled structure of Au nanoparticles. The hybrid shows good thermal stability up to 400 degrees C, beyond which the Au particles start migrating inside the SiO2 matrix. This study provides an insight in the formation mechanism and thermal stability of the structures which are crucial factors for designing and applying such hybrids in fields of catalysis and biotechnology. As the method is general, it can be applied to make similar hybrids based on SiO2 by tuning the reaction chemistry as needed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000333634800036 |
Publication Date |
2014-03-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1433-7851; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.994 |
Times cited |
10 |
Open Access |
OpenAccess |
Notes |
This research has received funding from the European Community’s Seventh Framework Program (ERC; grant number 246791)— COUNTATOMS, COLOURATOMS, as well as from the IAP 7/05 Programme initiated by the Belgian Science Policy Office. Funding from the Department of Science and Technology (DST) is also acknowledged.; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 11.994; 2014 IF: 11.261 |
Call Number |
UA @ lucian @ c:irua:117186 |
Serial |
1251 |
Permanent link to this record |
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|
|
Author |
Lueangchaichaweng, W.; Brooks, N.R.; Fiorilli, S.; Gobechiya, E.; Lin, K.; Li, L.; Parres-Esclapez, S.; Javon, E.; Bals, S.; Van Tendeloo, G.; Martens, J.A.; Kirschhock, C.E.A.; Jacobs, P.A.; Pescarmona, P.P.; |
Title |
Gallium oxide nanorods : novel, template-free synthesis and high catalytic activity in epoxidation reactions |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
53 |
Issue |
6 |
Pages |
1585-1589 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Gallium oxide nanorods with unprecedented small dimensions (20-80nm length and 3-5nm width) were prepared using a novel, template-free synthesis method. This nanomaterial is an excellent heterogeneous catalyst for the sustainable epoxidation of alkenes with H2O2, rivaling the industrial benchmark microporous titanosilicate TS-1 with linear alkenes and being much superior with bulkier substrates. A thorough characterization study elucidated the correlation between the physicochemical properties of the gallium oxide nanorods and their catalytic performance, and underlined the importance of the nanorod morphology for generating a material with high specific surface area and a high number of accessible acid sites. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000330558400021 |
Publication Date |
2014-01-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1433-7851; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.994 |
Times cited |
61 |
Open Access |
OpenAccess |
Notes |
START 1; Methusalem; Prodex; IAP-PAI; and the ERC (grant number 24691-COUNTATOMS and grant number 335078-COLOURATOM) projects; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 11.994; 2014 IF: 11.261 |
Call Number |
UA @ lucian @ c:irua:115726 |
Serial |
1314 |
Permanent link to this record |
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|
Author |
Pospisilova, A.; Filippov, S.K.; Bogomolova, A.; Turner, S.; Sedlacek, O.; Matushkin, N.; Cernochova, Z.; Stepanek, P.; Hruby, M. |
Title |
Glycogen-graft-poly(2-alkyl-2-oxazolines) – the new versatile biopolymer-based thermoresponsive macromolecular toolbox |
Type |
A1 Journal article |
Year |
2014 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
Volume |
4 |
Issue |
106 |
Pages |
61580-61588 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This study is focused on thermoresponsive glycogen-graft-poly(2-alkyl-2-oxazolines), a new group of nanostructured hybrid dendrimeric stimuli-responsive polymers connecting the body's own biodegradable polysaccharidic dendrimer glycogen with the widely tuneable thermoresponsive behavior of polypeptide-analogic poly(2-alkyl-2-oxazolines), which are known to be biocompatible. Glycogen-graft-poly(2-alkyl-2-oxazolines) were prepared by a simple one-pot two-step procedure involving cationic ring-opening polymerization of 2-alkyl-2-oxazolines followed by termination of the living cationic ends with sodium glycogenate. As confirmed by light and X-ray scattering, as well as cryo-transmission electron microscopy, the grafted dendrimer structure allows easy adjustment of the cloud point temperature, the concentration dependence and nanostructure of the self-assembled phase separated polymer by crosstalk during graft composition, the graft length and the grafting density, in a very wide range. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000345656600045 |
Publication Date |
2014-11-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2046-2069; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.108 |
Times cited |
15 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
Call Number |
UA @ lucian @ c:irua:122222 |
Serial |
1355 |
Permanent link to this record |
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|
|
Author |
Bertels, E.; Bruyninckx, K.; Kurttepeli; Smet, M.; Bals, S.; Goderis, B. |
Title |
Highly Efficient Hyperbranched CNT Surfactants: Influence of Molar Mass and Functionalization |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Langmuir: the ACS journal of surfaces and colloids |
Abbreviated Journal |
Langmuir |
Volume |
30 |
Issue |
41 |
Pages |
12200-12209 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
End-group-functionalized hyperbranched polymers were synthesized to act as a carbon nanotube (CNT) surfactant in aqueous solutions. Variation of the percentage of triphenylmethyl (trityl) functionalization and of the molar mass of the hyperbranched polyglycerol (PG) core resulted in the highest measured surfactant efficiency for a 5000 g/mol PG with 5.6% of the available hydroxyl end-groups replaced by trityl functions, as shown by UV-vis measurements. Semiempirical model calculations suggest an even higher efficiency for PG5000 with 2.5% functionalization and maximal molecule specific efficiency in general at low degrees of functionalization. Addition of trityl groups increases the surfactant-nanotube interactions in comparison to unfunctionalized PG because of pi-pi stacking interactions. However, at higher functionalization degrees mutual interactions between trityl groups come into play, decreasing the surfactant efficiency, while lack of water solubility becomes an issue at very high functionalization degrees. Low molar mass surfactants are less efficient compared to higher molar mass species most likely because the higher bulkiness of the latter allows for a better CNT separation and stabilization. The most efficient surfactant studied allowed dispersing 2.85 mg of CNT in 20 mL with as little as 1 mg of surfactant. These dispersions, remaining stable for at least 2 months, were mainly composed of individual CNTs as revealed by electron microscopy. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000343638800013 |
Publication Date |
2014-09-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0743-7463;1520-5827; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.833 |
Times cited |
15 |
Open Access |
OpenAccess |
Notes |
The authors gratefully acknowledge the SIM NanoForce programme for their financial support and thank the group of Prof. Thierry Verbiest, especially Maarten Bloemen, for the use of their UV−vis equipment. Bart Goderis and Mario Smet thank KU Leuven for financial support through a GOA project. Mert Kurttepeli and Sara Bals acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 335078 COLOURATOMS.; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 3.833; 2014 IF: 4.457 |
Call Number |
UA @ lucian @ c:irua:121140 |
Serial |
1471 |
Permanent link to this record |
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|
|
Author |
Shan, L.; Punniyakoti, S.; Van Bael, M.J.; Temst, K.; Van Bael, M.K.; Ke, X.; Bals, S.; Van Tendeloo, G.; D'Olieslaeger, M.; Wagner, P.; Haenen, K.; Boyen, H.G.; |
Title |
Homopolymers as nanocarriers for the loading of block copolymer micelles with metal salts : a facile way to large-scale ordered arrays of transition-metal nanoparticles |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
Volume |
2 |
Issue |
4 |
Pages |
701-707 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A new and facile approach is presented for generating quasi-regular patterns of transition metal-based nanoparticles on flat substrates exploiting polystyrene-block-poly2vinyl pyridine (PS-b-P2VP) micelles as intermediate templates. Direct loading of such micellar nanoreactors by polar transition metal salts in solution usually results in nanoparticle ensembles exhibiting only short range order accompanied by broad distributions of particle size and inter-particle distance. Here, we demonstrate that the use of P2VP homopolymers of appropriate length as molecular carriers to transport precursor salts into the micellar cores can significantly increase the degree of lateral order within the final nanoparticle arrays combined with a decrease in spreading in particle size. Thus, a significantly extended range of materials is now available which can be exploited to study fundamental properties at the transition from clusters to solids by means of well-organized, well-separated, size-selected metal and metal oxide nanostructures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000329069900015 |
Publication Date |
2013-11-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2050-7526;2050-7534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.256 |
Times cited |
5 |
Open Access |
Not_Open_Access |
Notes |
FWO projects G.0456.12; 50 G.0346.09N; Methusalem project "NANO |
Approved |
Most recent IF: 5.256; 2014 IF: 4.696 |
Call Number |
UA @ lucian @ c:irua:113734 |
Serial |
1489 |
Permanent link to this record |
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|
|
Author |
Boulay, E.; Ragoen, C.; Idrissi, H.; Schryvers, D.; Godet, S. |
Title |
Influence of amorphous phase separation on the crystallization behavior of glass-ceramics in the BaO-TiO2-SiO2 system |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of non-crystalline solids |
Abbreviated Journal |
J Non-Cryst Solids |
Volume |
384 |
Issue |
|
Pages |
61-72 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The possible role of a prior amorphous phase separation on the subsequent crystallization has been the topic of vigorous debates over the last decades and has not yet been clarified, especially regarding the role of the interfaces created by the phase separation. This study proposes to focus on the interplay between a prior amorphous phase separation and the crystallization of fresnoite in the BaO-TiO2-SiO2 system. The crystallization behavior of a non-stoichiometric composition inside the miscibility gap (called APS) is compared with the stoichiometric composition (called FRES) and a non-stoichiometric composition outside the miscibility gap (called NoAPS). The crystallization mechanisms are compared using differential thermal analysis (DTA) by calculating the Avrami parameters and the activation energies as a function of the particle size. The DTA study shows that the two non-stoichiometric compositions exhibit a pronounced surface crystallization behavior whereas FRES undergoes bulk nucleation. This is supported by a multi-scale microstructure characterization. Furthermore, this study demonstrates that the amorphous phase separation and the associated interfaces do not play any significant role in the nucleation step. Moreover, transmission electron microscope (TEM) and local orientation measurements show that the growth of the dendrites is not hindered by the SiO2-rich droplets. The final stage of crystallization of APS is tentatively explained by two composition effects that must be further investigated: the viscosity effect and the formation of a eutectic. (C) 2013 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000329422400010 |
Publication Date |
2013-07-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3093; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.124 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.124; 2014 IF: 1.766 |
Call Number |
UA @ lucian @ c:irua:114782 |
Serial |
1614 |
Permanent link to this record |
|
|
|
Author |
Morozov, V.A.; Lazoryak, B.I.; Shmurak, S.Z.; Kiselev, A.P.; Lebedev, O.I.; Gauquelin, N.; Verbeeck, J.; Hadermann, J.; Van Tendeloo, G. |
Title |
Influence of the structure on the properties of NaxEuy(MoO4)z red phosphors |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
26 |
Issue |
10 |
Pages |
3238-3248 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Scheelite related compounds (A',A '')(n)[(B',B '')O-4](m) with B', B '' = W and/or Mo are promising new materials for red phosphors in pc-WLEDs (phosphor-converted white-light-emitting-diode) and solid-state lasers. Cation substitution in CaMoO4 of Ca2+ by the combination of Na+ and Eu3+, with the creation of A cation vacancies, has been investigated as a factor for controlling the scheelite-type structure and the luminescent properties. Na5Eu(MoO4)(4) and NaxEu(2-x)/33+square(2-x)/3MoO4 (0.138 <= x <= 0.5) phases with a scheelite-type structure were synthesized by the solid state method; their structural characteristics were investigated using transmission electron microscopy. Contrary to powder synchrotron X-ray diffraction before, the study by electron diffraction and high resolution transmission electron microscopy in this paper revealed that Na0.286Eu0.571MoO4 has a (3 + 2)D incommensurately modulated structure and that (3 + 2)D incommensurately modulated domains are present in Na0.200Eu0.600MoO4. It also confirmed the (3 + 1)D incommensurately modulated character of Na(0.138)Eu(0.621)Mo04. The luminescent properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of these phosphors show the strongest absorption at about 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The emission spectra indicate an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+, with local minima in the intensity at Na0.286Eu0.571MoO4 and Na0.200Eu0.600MoO4 for similar to 613 nm and similar to 616 nm bands. The phosphor Na5Eu(MoO4)(4) shows the brightest red light emission among the phosphors in the Na2MoO4-Eu2/3MoO4 system and the maximum luminescence intensity of Na5Eu(MoO4)(4) (lambda(ex) = 395 nm) in the D-5(0) -> F-7(2) transition region is close to that of the commercially used red phosphor YVO4:Eu3+ (lambda(ex) = 326 nm). Electron energy loss spectroscopy measurements revealed the influence of the structure and Na/Eu cation distribution on the number and positions of bands in the UV-optical-infrared regions of the EELS spectrum. |
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 |
000336637000028 |
Publication Date |
2014-05-01 |
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 |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
53 |
Open Access |
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Notes |
Fwo G039211n; Fwo G004413n; 278510 Vortex ECASJO_; |
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
Call Number |
UA @ lucian @ c:irua:117765UA @ admin @ c:irua:117765 |
Serial |
1652 |
Permanent link to this record |
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Author |
Lu, J.; Roeffaers, M.B.J.; Bartholomeeusen, E.; Sels, B.F.; Schryvers, D. |
Title |
Intergrowth of components and ramps in coffin-shaped ZSM-5 zeolite crystals unraveled by focused ion beam-assisted transmission electron microscopy |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
20 |
Issue |
1 |
Pages |
42-49 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Scanning electron microscopy, focused ion beam (FIB), and transmission electron microscopy are combined to study the intergrowth of 90 degrees rotational components and of ramps in coffin-shaped ZSM-5 crystals. The 90 degrees rotational boundaries with local zig-zag features between different intergrowth components are observed in the main part of crystal. Also a new kind of displacement boundary is described. At the displacement boundary there is a shift of the unit cells along the boundary without a change in orientation. Based on lamellae prepared with FIB from different positions of the ramps and crystal, the orientation relationships between ramps and the main part of the crystal are studied and the three-dimensional morphology and growth mechanism of the ramp are illustrated. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge, Mass. |
Editor |
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Language |
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Wos |
000335378400006 |
Publication Date |
2013-11-05 |
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 |
1431-9276;1435-8115; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.891; 2014 IF: 1.877 |
Call Number |
UA @ lucian @ c:irua:117688 |
Serial |
1697 |
Permanent link to this record |
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Author |
Schattschneider, P.; Löffler, S.; Stöger-Pollach, M.; Verbeeck, J. |
Title |
Is magnetic chiral dichroism feasible with electron vortices? |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
136 |
Issue |
|
Pages |
81-85 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We discuss the feasibility of detecting magnetic transitions with focused electron vortex probes, suggested by selection rules for the magnetic quantum number. We theoretically estimate the dichroic signal strength in the L2,3 edge of ferromagnetic d metals. It is shown that under realistic conditions, the dichroic signal is undetectable for nanoparticles larger than View the MathML source. This is confirmed by a key experiment with nanometer-sized vortices. |
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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 |
000327884700011 |
Publication Date |
2013-07-26 |
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; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
64 |
Open Access |
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Notes |
Countatoms; Vortex; Esteem2; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
Call Number |
UA @ lucian @ c:irua:110952UA @ admin @ c:irua:110952 |
Serial |
1750 |
Permanent link to this record |
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Author |
Lu, J.; Martinez, G.T.; Van Aert, S.; Schryvers, D. |
Title |
Lattice deformations in quasi-dynamic strain glass visualised and quantified by aberration corrected electron microscopy |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
251 |
Issue |
10 |
Pages |
2034-2040 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Advanced transmission electron microscopy and statistical parameter estimated quantification procedures were applied to study the room temperature quasi-dynamical strain glass state in NiTi alloys. Nanosized strain pockets are visualised and the displacements of the atom columns are quantified. A comparison is made with conventional high-resolution transmission electron microscopy images of point defect induced strains in NiAl alloys. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000344360000009 |
Publication Date |
2014-03-31 |
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 |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.674 |
Times cited |
2 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 1.674; 2014 IF: 1.489 |
Call Number |
UA @ lucian @ c:irua:120471 |
Serial |
1801 |
Permanent link to this record |
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Author |
Béché, A.; Van Boxem, R.; Van Tendeloo, G.; Verbeeck, J. |
Title |
Magnetic monopole field exposed by electrons |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
Volume |
10 |
Issue |
1 |
Pages |
26-29 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The experimental search for magnetic monopole particles(1-3) has, so far, been in vain. Nevertheless, these elusive particles of magnetic charge have fuelled a rich field of theoretical study(4-10). Here, we created an approximation of a magnetic monopole in free space at the end of a long, nanoscopically thin magnetic needle(11). We experimentally demonstrate that the interaction of this approximate magnetic monopole field with a beam of electrons produces an electron vortex state, as theoretically predicted for a true magnetic monopole(3,11-18). This fundamental quantum mechanical scattering experiment is independent of the speed of the electrons and has consequences for all situations where electrons meet such monopole magnetic fields, as, for example, in solids. The set-up not only shows an attractive way to produce electron vortex states but also provides a unique insight into monopole fields and shows that electron vortices might well occur in unexplored solid-state physics situations. |
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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 |
000328940100012 |
Publication Date |
2013-11-29 |
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 |
1745-2473;1745-2481; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
22.806 |
Times cited |
131 |
Open Access |
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Notes |
Vortex; Countatoms; Fwo ECASJO_; |
Approved |
Most recent IF: 22.806; 2014 IF: 20.147 |
Call Number |
UA @ lucian @ c:irua:113740UA @ admin @ c:irua:113740 |
Serial |
1885 |
Permanent link to this record |
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Author |
Guzzinati, G.; Clark, L.; Béché, A.; Verbeeck, J. |
Title |
Measuring the orbital angular momentum of electron beams |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
Volume |
89 |
Issue |
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Pages |
025803 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The recent demonstration of electron vortex beams has opened up the new possibility of studying orbital angular momentum (OAM) in the interaction between electron beams and matter. To this aim, methods to analyze the OAM of an electron beam are fundamentally important and a necessary next step. We demonstrate the measurement of electron beam OAM through a variety of techniques. The use of forked holographic masks, diffraction from geometric apertures, and diffraction from a knife edge and the application of an astigmatic lens are all experimentally demonstrated. The viability and limitations of each are discussed with supporting numerical simulations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000332224100014 |
Publication Date |
2014-02-13 |
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 |
1050-2947;1094-1622; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.925 |
Times cited |
42 |
Open Access |
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Notes |
Vortex; FP7; Countatoms; ESTEEM2; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 2.925; 2014 IF: 2.808 |
Call Number |
UA @ lucian @ c:irua:114577UA @ admin @ c:irua:114577 |
Serial |
1972 |
Permanent link to this record |
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Author |
Zaghi, A.E.; Buffière, M.; Brammertz, G.; Batuk, M.; Lenaers, N.; Kniknie, B.; Hadermann, J.; Meuris, M.; Poortmans, J.; Vleugels, J. |
Title |
Mechanical synthesis of high purity Cu-In-Se alloy nanopowder as precursor for printed CISe thin film solar cells |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Advanced powder technology |
Abbreviated Journal |
Adv Powder Technol |
Volume |
25 |
Issue |
4 |
Pages |
1254-1261 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Mechanical alloying and ball milling are low cost, up-scalable techniques for the preparation of high purity chalcogenide nanopowders to be used as precursor material for printing thin film solar cells. In this study, high purity copper indium selenium (Cu-In-Se) alloy nanopowders with 20-200 nm particle size were synthesized from macroscopic elemental Cu, In and Se powders via mechanical alloying and planetary ball milling. The particle size distribution, morphology, composition, and purity level of the synthesized Cu-In-Se alloy nanopowders were investigated. Thin Cu-In-Se alloy nanopowder ink coatings, deposited on Mo-coated glass substrates by doctor blading, were converted into a CuInSe2 semiconductor film by selenization heat treatment in Se vapor. The CuInSe2 film showed semiconducting band gap around 1 eV measured by photoluminescence spectroscopy. CuInSe2 absorber layer based thin film solar cell devices were fabricated to assess their performance. The solar cell device showed a total efficiency of 4.8%, as measured on 0.25 cm(2) area cell. (c) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Zeist |
Editor |
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Language |
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Wos |
000341871700015 |
Publication Date |
2014-03-17 |
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 |
0921-8831; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.659 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.659; 2014 IF: 2.638 |
Call Number |
UA @ lucian @ c:irua:119896 |
Serial |
1977 |
Permanent link to this record |
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Author |
Buffière, M.; Brammertz, G.; Batuk, M.; Verbist, C.; Mangin, D.; Koble, C.; Hadermann, J.; Meuris, M.; Poortmans, J. |
Title |
Microstructural analysis of 9.7% efficient Cu2ZnSnSe4 thin film solar cells |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
105 |
Issue |
18 |
Pages |
183903 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This work presents a detailed analysis of the microstructure and the composition of our record Cu 2ZnSnSe4 (CZTSe)-CdS-ZnO solar cell with a total area efficiency of 9.7%. The average composition of the CZTSe crystallites is Cu 1.94 Zn 1.12Sn0.95Se3.99. Large crystals of ZnSe secondary phase (up to 400 nm diameter) are observed at the voids between the absorber and the back contact, while smaller ZnSe domains are segregated at the grain boundaries and close to the surface of the CZTSe grains. An underlying layer and some particles of Cu xSe are observed at the Mo-MoSe2-Cu2ZnSnSe4 interface. The free surface of the voids at the back interface is covered by an amorphous layer containing Cu, S, O, and C, while the presence of Cd, Na, and K is also observed in this region. |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000345000000086 |
Publication Date |
2014-11-08 |
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 |
0003-6951;1077-3118; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
17 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2014 IF: 3.302 |
Call Number |
UA @ lucian @ c:irua:121329 |
Serial |
2038 |
Permanent link to this record |