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Records |
Links |
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Author |
De wael, A.; De Backer, A.; Jones, L.; Varambhia, A.; Nellist, P.D.; Van Aert, S. |
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Title |
Measuring Dynamic Structural Changes of Nanoparticles at the Atomic Scale Using Scanning Transmission Electron Microscopy |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys Rev Lett |
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| |
Volume |
124 |
Issue |
10 |
Pages |
106105 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract  |
We propose a new method to measure atomic scale dynamics of nanoparticles from experimental high-resolution annular dark field scanning transmission electron microscopy images. By using the so-called hidden Markov model, which explicitly models the possibility of structural changes, the number of atoms in each atomic column can be quantified over time. This newly proposed method outperforms the current atom-counting procedure and enables the determination of the probabilities and cross sections for surface diffusion. This method is therefore of great importance for revealing and quantifying the atomic structure when it evolves over time via adatom dynamics, surface diffusion, beam effects, or during in situ experiments. |
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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 |
000519718100015 |
Publication Date |
2020-03-13 |
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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 |
0031-9007 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.6 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 770887 and No. 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through grants to A.D.w. and A.D.B. and projects G.0502.18N and EOS 30489208. L.J. acknowledges the SFI AMBER Centre for support. A.V. and P.D.N. acknowledge the UK Engineering and Physical Sciences Council (EPSRC) for support (EP/K040375/1 and 1772738). A.V. also acknowledges Johnson-Matthey for support. We would like to thank Brian Theobald and Jonathan Sharman from JMTC Sonning for provision of the Pt sample. |
Approved |
Most recent IF: 8.6; 2020 IF: 8.462 |
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Call Number |
EMAT @ emat @c:irua:167148 |
Serial |
6347 |
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| Permanent link to this record |
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Author |
Chen, X.; Cao, S.; Ikeda, T.; Srivastava, V.; Snyder, G.J.; Schryvers, D.; James, R.D. |
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Title |
A weak compatibility condition for precipitation with application to the microstructure of PbTe-Sb2Te3 thermoelectrics |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
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| |
Volume |
59 |
Issue |
15 |
Pages |
6124-6132 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We propose a weak condition of compatibility between phases applicable to cases exhibiting full or partial coherence and Widmanstätten microstructure. The condition is applied to the study of Sb2Te3 precipitates in a PbTe matrix in a thermoelectric alloy. The weak condition of compatibility predicts elongated precipitates lying on a cone determined by a transformation stretch tensor. Comparison of this cone with the long directions of precipitates determined by a slice-and-view method of scanning electron microscopy combined with focused ion beam sectioning shows good agreement between theory and experiment. A further study of the morphology of precipitates by the Eshelby method suggests that interfacial energy also plays a role and gives an approximate value of interfacial energy per unit area of 250 dyn cm−1. |
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Corporate Author |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000294086900026 |
Publication Date |
2011-07-22 |
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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 |
1359-6454; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.301 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 5.301; 2011 IF: 3.755 |
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Call Number |
UA @ lucian @ c:irua:92388 |
Serial |
3911 |
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| Permanent link to this record |
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Author |
Croitoru, M.D.; van Dyck, D.; Van Aert, S.; Bals, S.; Verbeeck, J. |
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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 |
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| |
Volume |
106 |
Issue |
10 |
Pages |
933-940 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Vision lab |
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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. |
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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 |
000240397200006 |
Publication Date |
2006-05-10 |
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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 |
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Impact Factor |
2.843 |
Times cited |
18 |
Open Access |
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Notes |
Fwo; Fwo-V |
Approved |
Most recent IF: 2.843; 2006 IF: 1.706 |
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Call Number |
UA @ lucian @ c:irua:87604UA @ admin @ c:irua:87604 |
Serial |
876 |
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Author |
Verbruggen, S.W.; Keulemans, M.; Goris, B.; Blommaerts, N.; Bals, S.; Martens, J.A.; Lenaerts, S. |
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Title |
Plasmonic ‘rainbow’ photocatalyst with broadband solar light response for environmental applications |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
Appl Catal B-Environ |
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Volume |
188 |
Issue |
188 |
Pages |
147-153 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
We propose the concept of a ‘rainbow’ photocatalyst that consists of TiO2 modified with gold-silver alloy nanoparticles of various sizes and compositions, resulting in a broad plasmon absorption band that covers the entire UV–vis range of the solar spectrum. It is demonstrated that this plasmonic ‘rainbow’ photocatalyst is 16% more effective than TiO2 P25 under both simulated and real solar light for pollutant degradation at the solid-gas interface. With this we provide a promising strategy to maximize the spectral response for solar to chemical energy conversion. |
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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 |
000372677500016 |
Publication Date |
2016-02-03 |
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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 |
0926-3373 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.446 |
Times cited |
47 |
Open Access |
OpenAccess |
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Notes |
S.W.V. and B.G. acknowledge the Research Foundation—Flanders (FWO) for a postdoctoral fellowship. M.K. acknowledges IWT for the doctoral scholarship. S.B. acknowledges the European Research Council (ERC) for financial support through the ERC grant agreement no. 335078-COLOURATOM. J.A.M. acknowledges the Flemish government for long-term structural funding (Methusalem).; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); |
Approved |
Most recent IF: 9.446 |
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Call Number |
c:irua:130995 |
Serial |
4061 |
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Author |
Jorissen, B.; Covaci, L.; Partoens, B. |
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Title |
Comparative analysis of tight-binding models for transition metal dichalcogenides |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
SciPost physics core |
Abbreviated Journal |
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Volume |
7 |
Issue |
1 |
Pages |
004-30 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We provide a comprehensive analysis of the prominent tight-binding (TB) models for transition metal dichalcogenides (TMDs) available in the literature. We inspect the construction of these TB models, discuss their parameterization used and conduct a thorough comparison of their effectiveness in capturing important electronic properties. Based on these insights, we propose a novel TB model for TMDs designed for enhanced computational efficiency. Utilizing MoS2 as a representative case, we explain why specific models offer a more accurate description. Our primary aim is to assist researchers in choosing the most appropriate TB model for their calculations on TMDs. |
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Place of Publication |
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Wos |
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Publication Date |
2024-02-06 |
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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 |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:202983 |
Serial |
9012 |
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Author |
Nistor, L.; Bender, H.; Vantomme, A.; Wu, M.F.; van Landuyt, J.; O'Donnell, K.P.; Martin, R.; Jacobs, K.; Moerman, I. |
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Title |
Direct evidence of spontaneous quantum dot formation in a thick InGaN epilayer |
Type |
A1 Journal article |
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Year |
2000 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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| |
Volume |
77 |
Issue |
4 |
Pages |
507-509 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a direct observation of quantum dots formed spontaneously in a thick InGaN epilayer by high resolution transmission electron microscopy. Investigation of a (280 nm thick) In0.22Ga0.78N single layer, emitting in the blue/green spectral region, reveals quantum dots with estimated sizes in the range of 1.5-3 nm. Such sizes are in very good agreement with calculations based on the luminescence spectra of this specimen. (C) 2000 American Institute of Physics. [S0003-6951(00)00930-X]. |
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Corporate Author |
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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 |
000088225400016 |
Publication Date |
2002-07-26 |
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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; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
44 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2000 IF: 3.906 |
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Call Number |
UA @ lucian @ c:irua:103448 |
Serial |
712 |
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Author |
Van Aert, S.; de Backer, A.; Martinez, G.T.; Goris, B.; Bals, S.; Van Tendeloo, G.; Rosenauer, A. |
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Title |
Procedure to count atoms with trustworthy single-atom sensitivity |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
87 |
Issue |
6 |
Pages |
064107-6 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a method to reliably count the number of atoms from high-angle annular dark field scanning transmission electron microscopy images. A model-based analysis of the experimental images is used to measure scattering cross sections at the atomic level. The high sensitivity of these measurements in combination with a thorough statistical analysis enables us to count atoms with single-atom sensitivity. The validity of the results is confirmed by means of detailed image simulations. We will show that the method can be applied to nanocrystals of arbitrary shape, size, and atom type without the need for a priori knowledge about the atomic structure. |
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Corporate Author |
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Place of Publication |
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Wos |
000315144700006 |
Publication Date |
2013-02-20 |
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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 |
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Impact Factor |
3.836 |
Times cited |
106 |
Open Access |
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Notes |
FWO; 262348 ESMI; 312483 ESTEEM2;246791 COUNTATOMS; Hercules 3; esteem2_jra2 |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
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Call Number |
UA @ lucian @ c:irua:105674 |
Serial |
2718 |
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Author |
Theofanidis, S.A.; Galvita, V.V.; Poelman, H.; Dharanipragada, N.V.R.A.; Longo, A.; Meledina, M.; Van Tendeloo, G.; Detavernier, C.; Marin, G.B. |
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Title |
Fe-containing magnesium aluminate support for stability and carbon control during methane reforming |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
8 |
Issue |
7 |
Pages |
5983-5995 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a MgFexAl2-xO4 synthetic spinel, where x varies from 0 to 0.26, as support for Ni-based catalysts, offering stability and carbon control under various conditions of methane reforming. By incorporation of Fe into a magnesium aluminate spine!, a support is created with redox functionality and high thermal stability, as concluded from temporal analysis of products (TAP) experiments and redox cycling, respectively. A diffusion coefficient of 3 x 10(-17) m(2) s(-1) was estimated for lattice oxygen at 993 K from TAP experiments. X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) modeling identified that the incorporation of iron occurs as Fe3+ in the octahedral sites of the spinel lattice, replacing aluminum. Simulation of the X-ray absorption near edge structure (XANES) spectrum of the reduced support showed that 60 +/- 10% of iron was reduced from 3+ to 2+ at 1073 K, while there was no formation of metallic iron. A series of Ni/MgFexAl2-xO4 catalysts, where x varies from 0 to 0.26, was synthesized and reduced, yielding a supported Ni-Fe alloy. The evolution of the catalyst structure during H-2 temperature-programmed reduction (TPR) and CO2 temperature-programmed oxidation (TPO) was examined using time-resolved in situ XRD and XANES. During reforming, iron in both the support and alloy keeps control of carbon accumulation, as confirmed by O-2-TPO on the spent catalysts. By fine tuning the amount of Fe in MgFexAl2-xO4, a supported alloy was obtained with a Ni/Fe molar ratio of similar to 10, which was active for reforming and stable. By comparison of the performance of Ni-based catalysts with Fe either incorporated into or deposited onto the support, the location of Fe within the support proved crucial for the stability and carbon mitigation under reforming conditions. |
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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 |
000438475100034 |
Publication Date |
2018-05-22 |
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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 |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
18 |
Open Access |
OpenAccess |
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Notes |
; This work was supported by the FAST industrialization by Catalyst Research and Development (FASTCARD) project, which is a Large Scale Collaborative Project supported by the European Commission in the 7th Framework Programme (GA no 604277), the “Long Term Structural Methusalem Funding by the Flemish Government”, the Interuniversity Attraction Poles Programme, IAP7/5, Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of travel costs and beam time at the DUBBLE beamline of the ESRF. The authors acknowledge the assistance from the DUBBLE (ESRF, XAS campaign 26-01-1048) and ROCK staff (SOLEIL, proposal 201502561). The authors equally acknowledge support from a public grant overseen by the French National Research Agency (ANR) as part of the “Investissements d'Avenir” program (reference: ANR-10-EQPX-45) for the ROCK beamline and from Lukas Buelens and Rakesh Batchu (Laboratory for Chemical Technology, Ghent University) for the STEM measurements and TAP experiments, respectively. ; |
Approved |
Most recent IF: 10.614 |
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| |
Call Number |
UA @ lucian @ c:irua:153178 |
Serial |
5102 |
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Author |
Nistor, L.C.; Ghica, C.; Van Tendeloo, G. |
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Title |
Mesoseopic ordering in the 0.9 Pb(Mg1/3Nb2/3)O3-0.1 PbTiO3 relaxor ferroelectric : a HRTEM study |
Type |
A1 Journal article |
| |
Year |
2007 |
Publication |
Physica status solidi: C: conferences and critical reviews |
Abbreviated Journal |
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| |
Volume |
4 |
Issue |
3 |
Pages |
736-739 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a microstructural and compositional study of a 90% Pb(Mg1/3Nb2/3)O-3 – 10% PbTiO3 ceramic sample. High resolution transmission electron microscopy (HRTEM) revealed the presence of compositional ordered nano-domains (1 – 4 mn), observable in two specific orientations, [0 (1) over bar 1] and [1 1 (2) over bar]. However, the visibility and the ordering degree of the nano-domains on the HRTEM images are not at all obvious. Fourier filtering of the images clearly revealed the ordered domains. Antiphase boundaries lying in the (111) planes separate them, while (100) and (111) facets separate the ordered domains from the disordered matrix. Their shape is plate-like, not uniformly spread in the disordered matrix. Their average size varies in different regions of the sample, most probably due to a non-uniform distribution of Ti, as observed by energy dispersive X-ray spectroscopy. (c) 2007 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim. |
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Address |
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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 |
000246104300008 |
Publication Date |
2007-03-07 |
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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 |
1610-1634;1610-1642; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:94663 |
Serial |
2004 |
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Author |
Delville, R.; Schryvers, D. |
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Title |
Transmission electron microscopy study of combined precipitation of Ti2Ni(Pd) and Ti2Pd(Ni) in a Ti50Ni30Pd20 alloy |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Intermetallics |
Abbreviated Journal |
Intermetallics |
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| |
Volume |
18 |
Issue |
12 |
Pages |
2353-2360 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a new mode of precipitation in a B19 martensitic Ti50Ni30Pd20 shape memory alloy consisting of a central Ti2Ni(Pd) precipitate surrounded by an austenite area containing Ti2Pd(Ni) precipitates. The morphology and crystallography of the precipitation area is investigated using conventional and high resolution electron microscopy. In particular, the orientation relationship and the coherency strain between the Ti2Pd(Ni) precipitate and the surrounding retained B2 matrix are discussed. A study of local composition in relation with a ternary phase diagram using X-ray energy dispersive spectroscopy with a nanoprobe gives evidences of the formation mechanism. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Chicago, Ill. |
Editor |
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Language |
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Wos |
000284447500014 |
Publication Date |
2010-09-04 |
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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 |
0966-9795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.14 |
Times cited |
9 |
Open Access |
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Notes |
Multimat; Iap |
Approved |
Most recent IF: 3.14; 2010 IF: 2.335 |
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| |
Call Number |
UA @ lucian @ c:irua:84473 |
Serial |
3714 |
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Author |
Robert, Hl.; Lobato, I.; Lyu, Fj.; Chen, Q.; Van Aert, S.; Van Dyck, D.; Müller-Caspary, K. |
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Title |
Dynamical diffraction of high-energy electrons investigated by focal series momentum-resolved scanning transmission electron microscopy at atomic resolution |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
233 |
Issue |
|
Pages |
113425 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
We report a study of scattering dynamics in crystals employing momentum-resolved scanning transmission
electron microscopy under varying illumination conditions. As we perform successive changes of the probe
focus, multiple real-space signals are obtained in dependence of the shape of the incident electron wave.
With support from extensive simulations, each signal is shown to be characterised by an optimum focus for
which the contrast is maximum and which differs among different signals. For instance, a systematic focus
mismatch is found between images formed by high-angle scattering, being sensitive to thickness and chemical
composition, and the first moment in diffraction space, being sensitive to electric fields. It follows that a single
recording at one specific probe focus is usually insufficient to characterise materials comprehensively. Most
importantly, we demonstrate in experiment and simulation that the second moment ( |
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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 |
000734396800009 |
Publication Date |
2021-11-13 |
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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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.2 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
We thank Dr. Florian Winkler for valuable discussions and experimental work at the early stages of this study. This work was supported by the Initiative and Network Fund of the Helmholtz Association (Germany) under contracts VH-NG-1317 and ZT-I-0025. This project furthermore received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. 770887). |
Approved |
Most recent IF: 2.2 |
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| |
Call Number |
EMAT @ emat @c:irua:184833 |
Serial |
6898 |
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| Permanent link to this record |
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Author |
Groeneveld, E.; Witteman, L.; Lefferts, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; de Mello Donega, C. |
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Title |
Tailoring ZnSe-CdSe colloidal quantum dots via cation exchange : from core/shell to alloy nanocrystals |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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| |
Volume |
7 |
Issue |
9 |
Pages |
7913-7930 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a study of Zn2+ by Cd2+ cation exchange (CE) in colloidal ZnSe nanocrystals (NCs). Our results reveal that CE in ZnSe NCs is a thermally activated isotropic process. The CE efficiency (i.e., fraction of Cd2+ ions originally in solution, Cdsol, that is incorporated in the ZnSe NC) increases with temperature and depends also on the Cdsol/ZnSe ratio. Interestingly, the reaction temperature can be used as a sensitive parameter to tailor both the composition and the elemental distribution profile of the product (Zn,Cd)Se NCs. At 150 °C ZnSe/CdSe core/shell hetero-NCs (HNCs) are obtained, while higher temperatures (200 and 220 °C) produce (Zn1xCdx)Se gradient alloy NCs, with increasingly smoother gradients as the temperature increases, until homogeneous alloy NCs are obtained at T ≥ 240 °C. Remarkably, sequential heating (150 °C followed by 220 °C) leads to ZnSe/CdSe core/shell HNCs with thicker shells, rather than (Zn1xCdx)Se gradient alloy NCs. Thermal treatment at 250 °C converts the ZnSe/CdSe core/shell HNCs into (Zn1xCdx)Se homogeneous alloy NCs, while preserving the NC shape. A mechanism for the cation exchange in ZnSe NCs is proposed, in which fast CE takes place at the NC surface, and is followed by relatively slower thermally activated solid-state cation diffusion, which is mediated by Frenkel defects. The findings presented here demonstrate that cation exchange in colloidal ZnSe NCs provides a very sensitive tool to tailor the nature and localization regime of the electron and hole wave functions and the optoelectronic properties of colloidal ZnSeCdSe NCs. |
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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 |
000330016900051 |
Publication Date |
2013-08-13 |
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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 |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
153 |
Open Access |
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| |
Notes |
262348 Esmi; 246791 Countatoms |
Approved |
Most recent IF: 13.942; 2013 IF: 12.033 |
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Call Number |
UA @ lucian @ c:irua:110038 |
Serial |
3469 |
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| Permanent link to this record |
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Author |
Jungbauer, M.; Huehn, S.; Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.; Moshnyaga, V. |
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Title |
Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO3)n films by means of metalorganic aerosol deposition |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
| |
Volume |
105 |
Issue |
25 |
Pages |
251603 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO3)(n) (n = infinity, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO3(001) substrates by means of a sequential deposition of Sr-O/Ti-O-2 atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2-4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5-6 repetitions of the SrO(SrTiO3)(4) block at the level of 2.4%. This identifies the SrTiO3 substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy. (C) 2014 AIP Publishing LLC. |
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Address |
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Corporate Author |
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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 |
000346914000007 |
Publication Date |
2014-12-26 |
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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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.411 |
Times cited |
32 |
Open Access |
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| |
Notes |
246102 IFOX; 278510 VORTEX; 246791 COUNTATOMS; Hercules; 312483 ESTEEM2; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 3.411; 2014 IF: 3.302 |
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Call Number |
UA @ lucian @ c:irua:122830UA @ admin @ c:irua:122830 |
Serial |
172 |
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| Permanent link to this record |
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Author |
Gonnissen, J.; de Backer, A.; den Dekker, A.J.; Martinez, G.T.; Rosenauer, A.; Sijbers, J.; Van Aert, S. |
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Title |
Optimal experimental design for the detection of light atoms from high-resolution scanning transmission electron microscopy images |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
| |
Volume |
105 |
Issue |
6 |
Pages |
063116 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
We report an innovative method to explore the optimal experimental settings to detect light atoms from scanning transmission electron microscopy (STEM) images. Since light elements play a key role in many technologically important materials, such as lithium-battery devices or hydrogen storage applications, much effort has been made to optimize the STEM technique in order to detect light elements. Therefore, classical performance criteria, such as contrast or signal-to-noise ratio, are often discussed hereby aiming at improvements of the direct visual interpretability. However, when images are interpreted quantitatively, one needs an alternative criterion, which we derive based on statistical detection theory. Using realistic simulations of technologically important materials, we demonstrate the benefits of the proposed method and compare the results with existing approaches. |
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Corporate Author |
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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 |
000341188700073 |
Publication Date |
2014-08-14 |
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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 |
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Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
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Notes |
FWO (G.0393.11; G.0064.10; and G.0374.13); European Union Seventh Framework Programme [FP7/2007-2013] under Grant Agreement No. 312483 (ESTEEM2); esteem2_jra2 |
Approved |
Most recent IF: 3.411; 2014 IF: 3.302 |
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Call Number |
UA @ lucian @ c:irua:118333 |
Serial |
2482 |
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Author |
Kalkert, C.; Krisponeit, J.-O.; Esseling, M.; Lebedev, O.I.; Moshnyaga, V.; Damaschke, B.; Van Tendeloo, G.; Samwer, K. |
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Title |
Resistive switching at manganite/manganite interfaces |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
| |
Volume |
99 |
Issue |
13 |
Pages |
132512-132512,3 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report bipolar resistive switching between the interfaces of manganite nanocolumns. La0.7Sr0.3MnO3 films were prepared on Al2O3 substrates, where the films grow in nanocolumns from the substrate to the surface. Conductive atomic force microscopy directly detects that the resistive switching is located at the boundaries of the grains. Furthermore, mesoscopic transport measurements reveal a tunnel magnetoresistance. In combination with the resistive switching, this leads to a total of four different resistive states. |
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Corporate Author |
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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 |
000295618000052 |
Publication Date |
2011-09-29 |
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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; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
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Call Number |
UA @ lucian @ c:irua:91884 |
Serial |
2881 |
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Author |
Araizi-Kanoutas, G.; Geessinck, J.; Gauquelin, N.; Smit, S.; Verbeek, X.H.; Mishra, S.K.; Bencok, P.; Schlueter, C.; Lee, T.-L.; Krishnan, D.; Fatermans, J.; Verbeeck, J.; Rijnders, G.; Koster, G.; Golden, M.S. |
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Title |
Co valence transformation in isopolar LaCoO3/LaTiO3 perovskite heterostructures via interfacial engineering |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical review materials |
Abbreviated Journal |
Phys. Rev. Materials |
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Volume |
4 |
Issue |
2 |
Pages |
026001 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report charge transfer up to a single electron per interfacial unit cell across nonpolar heterointerfaces from the Mott insulator LaTiO3 to the charge transfer insulator LaCoO3. In high-quality bi- and trilayer systems grown using pulsed laser deposition, soft x-ray absorption, dichroism, and scanning transmission electron microscopy-electron energy loss spectroscopy are used to probe the cobalt-3d electron count and provide an element-specific investigation of the magnetic properties. The experiments show the cobalt valence conversion is active within 3 unit cells of the heterointerface, and able to generate full conversion to 3d7 divalent Co, which displays a paramagnetic ground state. The number of LaTiO3/LaCoO3 interfaces, the thickness of an additional, electronically insulating “break” layer between the LaTiO3 and LaCoO3, and the LaCoO3 film thickness itself in trilayers provide a trio of control knobs for average charge of the cobalt ions in LaCoO3, illustrating the efficacy of O−2p band alignment as a guiding principle for property design in complex oxide heterointerfaces. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
000513551200007 |
Publication Date |
2020-02-10 |
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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 |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
13 |
Open Access |
OpenAccess |
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Notes |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Horizon 2020, 730872 ; Department of Science and Technology, Ministry of Science and Technology, SR/NM/Z-07/2015 ; Jawaharlal Nehru Centre for Advanced Scientific Research; |
Approved |
Most recent IF: 3.4; 2020 IF: NA |
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Call Number |
EMAT @ emat @c:irua:167787 |
Serial |
6376 |
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Author |
Gou, H.; Tsirlin, A.A.; Bykova, E.; Abakumov, A.M.; Van Tendeloo, G.; Richter, A.; Ovsyannikov, S.V.; Kurnosov, A.V.; Trots, D.M.; Konôpková, Z.; Liermann, H.P.; Dubrovinsky, L.; Dubrovinskaia, N.; |
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Title |
Peierls distortion, magnetism, and high hardness of manganese tetraboride |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
89 |
Issue |
6 |
Pages |
064108-64109 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report crystal structure, electronic structure, and magnetism of manganese tetraboride, MnB4, synthesized under high-pressure, high-temperature conditions. In contrast to superconducting FeB4 and metallic CrB4, which are both orthorhombic, MnB4 features a monoclinic crystal structure. Its lower symmetry originates from a Peierls distortion of the Mn chains. This distortion nearly opens the gap at the Fermi level, but despite the strong dimerization and the proximity of MnB4 to the insulating state, we find indications for a sizable paramagnetic effective moment of about 1.7 mu(B)/f.u., ferromagnetic spin correlations, and, even more surprisingly, a prominent electronic contribution to the specific heat. However, no magnetic order has been observed in standard thermodynamic measurements down to 2 K. Altogether, this renders MnB4 a structurally simple but microscopically enigmatic material; we argue that its properties may be influenced by electronic correlations. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000332405000002 |
Publication Date |
2014-02-24 |
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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 |
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Impact Factor |
3.836 |
Times cited |
39 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.836; 2014 IF: 3.736 |
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Call Number |
UA @ lucian @ c:irua:115819 |
Serial |
2571 |
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Author |
Klimczuk, T.; Wang, C.H.; Lawrence, J.M.; Xu, Q.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Trouw, F.; Kurita, N.; Tokiwa, Y.; Lee, H.o.; Booth, C.H.; Gardner, J.S.; Bauer, E.D.; Joyce, J.J.; Zandbergen, H.W.; Movshovich, R.; Cava, R.J.; Thompson, J.D.; |
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Title |
Crystal fields, disorder, and antiferromagnetic short-range order in Yb0.24Sn0.76Ru |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
84 |
Issue |
7 |
Pages |
075152-075152,8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report extensive measurements on a new compound (Yb0.24Sn0.76)Ru that crystallizes in the cubic CsCl structure. Valence-band photoemission (PES) and L3 x-ray absorption show no divalent component in the 4f configuration of Yb. Inelastic neutron scattering (INS) indicates that the eight-fold degenerate J-multiplet of Yb3+ is split by the crystalline electric field (CEF) into a Γ7-doublet ground state and a Γ8 quartet at an excitation energy 20 meV. The magnetic susceptibility can be fit very well by this CEF scheme under the assumption that a Γ6-excited state resides at 32 meV; however, the Γ8/Γ6 transition expected at 12 meV was not observed in the INS. The resistivity follows a Bloch-Grüneisen law shunted by a parallel resistor, as is typical of systems subject to phonon scattering with no apparent magnetic scattering. All of these properties can be understood as representing simple local moment behavior of the trivalent Yb ion. At 1 K there is a peak in specific heat that is too broad to represent a magnetic-phase transition, consistent with absence of magnetic reflections in neutron diffraction. On the other hand this peak also is too narrow to represent the Kondo effect in the Γ7-doublet ground state. On the basis of the field dependence of the specific heat, we argue that antiferromagnetic (AF) short-range order (SRO) (possibly coexisting with Kondo physics) occurs at low temperatures. The long-range magnetic order is suppressed because the Yb site occupancy is below the percolation threshold for this disordered compound. |
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Place of Publication |
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Language |
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Wos |
000293830800003 |
Publication Date |
2011-08-15 |
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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 |
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Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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Call Number |
UA @ lucian @ c:irua:92427 |
Serial |
555 |
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| Permanent link to this record |
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Author |
Shapoval, O.; Huehn, S.; Verbeeck, J.; Jungbauer, M.; Belenchuk, A.; Moshnyaga, V. |
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Title |
Interface-controlled magnetism and transport of ultrathin manganite films |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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| |
Volume |
113 |
Issue |
17 |
Pages |
17c711-3 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report ferromagnetic, T-C = 240 K, and metallic, T-MI = 250 K, behaviors of a three unit cell thick interface engineered lanthanum manganite film, grown by metalorganic aerosol deposition technique on SrTiO3(100) substrates. Atomically resolved electron microscopy and chemical analysis show that ultrathin manganite films start to grow with La-O layer on a strongly Mn/Ti-intermixed interface, engineered by an additional deposition of 2 u.c. of Sr-Mn-O. Such interface engineering results in a hole-doped manganite layer and stabilizes ferromagnetism and metallic conductivity down to the thickness of d = 3 u.c. The films with d = 8 u.c. demonstrate a bulk-like transport behavior with T-MI similar to T-C = 310 – 330 K. (C) 2013 American Institute of Physics. |
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Corporate Author |
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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 |
000319292800195 |
Publication Date |
2013-03-19 |
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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 |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
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| |
Notes |
Ifox; Countatoms; Vortex; Esteem2; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 2.068; 2013 IF: 2.185 |
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Call Number |
UA @ lucian @ c:irua:109009UA @ admin @ c:irua:109009 |
Serial |
1692 |
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Author |
Otero-Martinez, C.; Imran, M.; Schrenker, N.J.; Ye, J.; Ji, K.; Rao, A.; Stranks, S.D.; Hoye, R.L.Z.; Bals, S.; Manna, L.; Perez-Juste, J.; Polavarapu, L. |
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Title |
Fast A-site cation cross-exchange at room temperature : single-to double- and triple-cation halide perovskite nanocrystals |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
61 |
Issue |
34 |
Pages |
e202205617-11 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We report here fast A-site cation cross-exchange between APbX(3) perovskite nanocrystals (NCs) made of different A-cations (Cs (cesium), FA (formamidinium), and MA (methylammonium)) at room temperature. Surprisingly, the A-cation cross-exchange proceeds as fast as the halide (X=Cl, Br, or I) exchange with the help of free A-oleate complexes present in the freshly prepared colloidal perovskite NC solutions. This enabled the preparation of double (MACs, MAFA, CsFA)- and triple (MACsFA)-cation perovskite NCs with an optical band gap that is finely tunable by their A-site composition. The optical spectroscopy together with structural analysis using XRD and atomically resolved high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and integrated differential phase contrast (iDPC) STEM indicates the homogeneous distribution of different cations in the mixed perovskite NC lattice. Unlike halide ions, the A-cations do not phase-segregate under light illumination. |
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Place of Publication |
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Wos |
000823857300001 |
Publication Date |
2022-06-24 |
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ISSN |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
16.6 |
Times cited |
28 |
Open Access |
OpenAccess |
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Notes |
L.P. acknowledges the support from the Spanish Ministerio de Ciencia e Innovacion through Ramon y Cajal grant (RYC2018-026103-I) and the Spanish State Research Agency (Grant No. PID2020-117371RA-I00), the grant from the Xunta de Galicia (ED431F2021/05). N.J.S. acknowledges financial support from the Research Foundation-Flanders via a postdoctoral fellowship (FWO Grant No. 1238622N). S.B. thanks the financial support of the European Research Council (ERC-CoG-2019815128) and of the European Commission (EUSMI, Grant 731019). R.L.Z.H. thanks the Royal Academy of Engineering through the Research Fellowships scheme (No.: RF\201718\1701). S.D.S. and K.J. acknowledge the Royal Society for funding. S.D.S. acknowledges the Royal Society and Tata Group (UF150033). The work has received funding from the European Research Council under the European Union's Horizon 2020 research and innovation programme (HYPERION -grant agreement no. 756962). The authors acknowledge the Engineering and Physical Sciences Research Council (EPSRC) for funding (EP/R023980/1). M.I. and L.M. acknowledge financial support from the Italian Ministry of University and Research (MIUR) through the Flag-Era JTC2019 project “Solution-Processed Perovskite/Graphene Nanocomposites for Self-Powered Gas Sensors” (PeroGaS). The authors acknowledge the Universidade de Vigo/CISUG for open access funding. |
Approved |
Most recent IF: 16.6 |
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Call Number |
UA @ admin @ c:irua:189675 |
Serial |
7083 |
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Author |
Gasparotto, A.; Maccato, C.; Carraro, G.; Sada, C.; Štangar, U.L.; Alessi, B.; Rocks, C.; Mariotti, D.; La Porta, A.; Altantzis, T.; Barreca, D. |
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Title |
Surface Functionalization of Grown-on-Tip ZnO Nanopyramids: From Fabrication to Light-Triggered Applications |
Type |
A1 Journal Article |
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Year |
2019 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
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Volume |
11 |
Issue |
17 |
Pages |
15881-15890 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
We report on a combined chemical vapor deposition (CVD)/radio frequency (RF) sputtering synthetic strategy for the controlled surface modification of ZnO nanostructures by Ti-containing species. Specifically, the proposed approach consists in the CVD of grown-on-tip ZnO nanopyramids, followed by titanium RF sputtering under mild conditions. The results obtained by a thorough characterization demonstrate the successful ZnO surface functionalization with dispersed Ti-containing species in low amounts. This phenomenon, in turn, yields a remarkable enhancement of photoactivated superhydrophilic behavior, self-cleaning ability, and photocatalytic performances in comparison to bare ZnO. The reasons accounting for such an improvement are unravelled by a multitechnique analysis, elucidating the interplay between material chemico-physical properties and the corresponding functional behavior. Overall, the proposed strategy stands as an amenable tool for the mastering of semiconductor-based functional nanoarchitectures through ad hoc engineering of the system surface. |
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Wos |
000466988800078 |
Publication Date |
2019-04-18 |
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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 |
1944-8244 |
ISBN |
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Additional Links |
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Impact Factor |
7.504 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
The research leading to these results has received financial support from Padova University ACTION postdoc fellowship, DOR 2016-2018, P-DiSC #03BIRD2016-UNIPD projects, and HERALD COST Action MP1402-37831. The support from EPSRC (awards EP/R008841/1 and EP/M024938/1) as well as from the Slovenian Research Agency (research core funding No. P1-0134) is also recognized. T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). The authors are grateful to Dr. Sebastiano Pianta (Department of Chemical Sciences, Padova University, Italy) for experimental assistance. |
Approved |
Most recent IF: 7.504 |
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Call Number |
EMAT @ emat @ |
Serial |
5185 |
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Author |
Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. |
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Title |
Structural and electronic properties of defects at grain boundaries in CuInSe2 |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
19 |
Issue |
19 |
Pages |
14770-14780 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect
of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at
the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported. |
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Wos |
000403327200059 |
Publication Date |
2017-05-12 |
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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 |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
12 |
Open Access |
OpenAccess |
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Notes |
We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 4.123 |
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Call Number |
EMAT @ emat @ c:irua:143869 |
Serial |
4577 |
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Author |
Parente, A.; Gorlé, C.; van Beeck, J.; Benocci, C. |
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Title |
A comprehensive modelling approach for the neutral atmospheric boundary layer : consistent inflow conditions, wall function and turbulence model |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Boundary-layer meteorology |
Abbreviated Journal |
Bound-Lay Meteorol |
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Volume |
140 |
Issue |
3 |
Pages |
411-428 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on a novel approach for the Reynolds-averaged Navier-Stokes (RANS) modelling of the neutral atmospheric boundary layer (ABL), using the standard k− turbulence model. A new inlet condition for turbulent kinetic energy is analytically derived from the solution of the k− model transport equations, resulting in a consistent set of fully developed inlet conditions for the neutral ABL. A modification of the standard k− model is also employed to ensure consistency between the inlet conditions and the turbulence model. In particular, the turbulence model constant C μ is generalized as a location-dependent parameter, and a source term is introduced in the transport equation for the turbulent dissipation rate. The application of the proposed methodology to cases involving obstacles in the flow is made possible through the implementation of an algorithm, which automatically switches the turbulence model formulation when going from the region where the ABL is undisturbed to the region directly affected by the building. Finally, the model is completed with a slightly modified version of the Richards and Hoxey rough-wall boundary condition. The methodology is implemented and tested in the commercial code Ansys Fluent 12.1. Results are presented for a neutral boundary layer over flat terrain and for the flow around a single building immersed in an ABL. |
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Place of Publication |
Dordrecht |
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Wos |
000293923800004 |
Publication Date |
2011-05-25 |
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Edition |
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ISSN |
0006-8314;1573-1472; |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.573 |
Times cited |
54 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.573; 2011 IF: 1.737 |
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Call Number |
UA @ lucian @ c:irua:92341 |
Serial |
450 |
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Author |
Liu, Y.; Brelet, Y.; He, Z.; Yu, L.; Mitryukovskiy, S.; Houard, A.; Forestier, B.; Couairon, A.; Mysyrowicz, A. |
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Title |
Ciliary white light : optical aspect of ultrashort laser ablation on transparent dielectrics |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
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Volume |
110 |
Issue |
9 |
Pages |
097601-97605 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on a novel nonlinear optical phenomenon, coined as ciliary white light, during laser ablation of transparent dielectrics. It is observed in 14 different transparent materials including glasses, crystals, and polymers. This phenomenon is also universal with respect to laser polarization, pulse duration, and focusing geometry. We interpret its formation in terms of the nonlinear diffraction of the laser generated white light by the ablation crater covered by nanostructures. It carries rich information on the damage profile and morphology dynamics of the ablated surface, providing a real time in situ observation of the laser ablation process. DOI: 10.1103/PhysRevLett.110.097601 |
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Place of Publication |
New York, N.Y. |
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Wos |
000317186000007 |
Publication Date |
2013-03-01 |
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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 |
0031-9007;1079-7114; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.462 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 8.462; 2013 IF: 7.728 |
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Call Number |
UA @ lucian @ c:irua:108509 |
Serial |
360 |
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Author |
Kashiwar, A.; Hahn, H.; Kubel, C. |
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Title |
In situ TEM observation of cooperative grain rotations and the Bauschinger effect in nanocrystalline palladium |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Nanomaterials |
Abbreviated Journal |
Nanomaterials-Basel |
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Volume |
11 |
Issue |
2 |
Pages |
432 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on cooperative grain rotation accompanied by a strong Bauschinger effect in nanocrystalline (nc) palladium thin film. A thin film of nc Pd was subjected to cyclic loading-unloading using in situ TEM nanomechanics, and the evolving microstructural characteristics were investigated with ADF-STEM imaging and quantitative ACOM-STEM analysis. ADF-STEM imaging revealed a partially reversible rotation of nanosized grains with a strong out-of-plane component during cyclic loading-unloading experiments. Sets of neighboring grains were shown to rotate cooperatively, one after the other, with increasing/decreasing strain. ACOM-STEM in conjunction with these experiments provided information on the crystallographic orientation of the rotating grains at different strain levels. Local Nye tensor analysis showed significantly different geometrically necessary dislocation (GND) density evolution within grains in close proximity, confirming a locally heterogeneous deformation response. The GND density analysis revealed the formation of dislocation pile-ups at grain boundaries (GBs), indicating the generation of back stresses during unloading. A statistical analysis of the orientation changes of individual grains showed the rotation of most grains without global texture development, which fits to both dislocation- and GB sliding-based mechanisms. Overall, our quantitative in situ experimental approach explores the roles of these different deformation mechanisms operating in nanocrystalline metals during cyclic loading. |
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Wos |
000622951500001 |
Publication Date |
2021-02-14 |
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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 |
2079-4991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.553 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.553 |
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Call Number |
UA @ admin @ c:irua:176770 |
Serial |
6729 |
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Author |
Liu, J.; Jin, J.; Deng, Z.; Huang, S.Z.; Hu, Z.Y.; Wang, L.; Wang, C.; Chen, L.H.; Li, Y.; Van Tendeloo, G.; Su, B.L.; |
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Title |
Tailoring CuO nanostructures for enhanced photocatalytic property |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of colloid and interface science |
Abbreviated Journal |
J Colloid Interf Sci |
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Volume |
384 |
Issue |
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Pages |
1-9 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on one-pot synthesis of various morphologies of CuO nanostructures. PEG200 as a structure directing reagent under the synergism of alkalinity by hydrothermal method has been employed to tailor the morphology of CuO nanostructures. The CuO products have been characterized by XRD, SEM, and TEM. The morphologies of the CuO nanostructures can be tuned from 10 (nanoseeds, nanoribbons) to 2D (nanoleaves) and to 3D (shuttle-like, shrimp-like, and nanoflowers) by changing the volume of PEG200 and the alkalinity in the reaction system. At neutral and relatively low alkalinity (OH-/Cu2+ <= 3), the addition of PEG200 can strongly influence the morphologies of the CuO nanostructures. At high alkalinity (OH/Cu2+ >= 4), PEG200 has no influence on the morphology of the CuO nanostructure. The different morphologies of the CuO nanostructures have been used for the photodecomposition of the pollutant rhodamine B (RhB) in water. The photocatalytic activity has been correlated with the different nanostructures of CuO. The 10 CuO nanoribbons exhibit the best performance on the RhB photodecomposition because of the exposed high surface energy {-121} crystal plane. The photocatalytic results show that the high energy surface planes of the CuO nanostructures mostly affect the photocatalytic activity rather than the morphology of the CuO nanostructures. Our synthesis method also shows it is possible to control the morphologies of nanostructures in a simple way. (C) 2012 Elsevier Inc. All rights reserved. |
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Place of Publication |
New York, N.Y. |
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Wos |
000308337700001 |
Publication Date |
2012-06-27 |
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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 |
0021-9797; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.233 |
Times cited |
105 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.233; 2012 IF: 3.172 |
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Call Number |
UA @ lucian @ c:irua:101796 |
Serial |
3468 |
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Author |
Ghosh, S.; Gaspari, R.; Bertoni, G.; Spadaro, M.C.; Prato, M.; Turner, S.; Cavalli, A.; Manna, L.; Brescia, R. |
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Title |
Pyramid-Shaped Wurtzite CdSe Nanocrystals with Inverted Polarity |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume |
9 |
Issue |
9 |
Pages |
8537-8546 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on pyramid-shaped wurtzite cadmium selenide (CdSe) nanocrystals (NCs), synthesized by hot injection in the presence of chloride ions as shape-directing agents, exhibiting reversed crystal polarity compared to former reports. Advanced transmission electron microscopy (TEM) techniques (image-corrected high-resolution TEM with exit wave reconstruction and probe-corrected high-angle annular dark field-scanning TEM) unequivocally indicate that the triangular base of the pyramids is the polar (0001) facet and their apex points toward the [0001] direction. Density functional theory calculations, based on a simple model of binding of Cl(-) ions to surface Cd atoms, support the experimentally evident higher thermodynamic stability of the (0001) facet over the (0001) one conferred by Cl(-) ions. The relative stability of the two polar facets of wurtzite CdSe is reversed compared to previous experimental and computational studies on Cd chalcogenide NCs, in which no Cl-based chemicals were deliberately used in the synthesis or no Cl(-) ions were considered in the binding models. Self-assembly of these pyramids in a peculiar clover-like geometry, triggered by the addition of oleic acid, suggests that the basal (polar) facet has a density and perhaps type of ligands significantly different from the other three facets, since the pyramids interact with each other exclusively via their lateral facets. A superstructure, however with no long-range order, is observed for clovers with their (0001) facets roughly facing each other. The CdSe pyramids were also exploited as seeds for CdS pods growth, and the peculiar shape of the derived branched nanostructures clearly arises from the inverted polarity of the seeds. |
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Address |
Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego 30, I-16163 Genova, Italy |
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English |
Wos |
000360323300085 |
Publication Date |
2015-07-23 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
16 |
Open Access |
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Notes |
PMID:26203791 |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:127807 |
Serial |
3956 |
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Author |
Abakumov, A.M.; Batuk, D.; Tsirlin, A.A.; Prescher, C.; Dubrovinsky, L.; Sheptyakov, D.V.; Schnelle, W.; Hadermann, J.; Van Tendeloo, G. |
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Title |
Frustrated pentagonal Cairo lattice in the non-collinear antiferromagnet Bi4Fe5O13F |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
87 |
Issue |
2 |
Pages |
024423-24429 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the crystal structure and magnetism of the iron-based oxyfluoride Bi4Fe5O13F, a material prototype of the Cairo pentagonal spin lattice. The crystal structure of Bi4Fe5O13F is determined by a combination of neutron diffraction, synchrotron x-ray diffraction, and transmission electron microscopy. It comprises layers of FeO6 octahedra and FeO4 tetrahedra forming deformed pentagonal units. The topology of these layers resembles a pentagonal least-perimeter tiling, which is known as the Cairo lattice. This topology gives rise to frustrated exchange couplings and underlies a sequence of magnetic transitions at T-1 = 62 K, T-2 = 71 K, and T-N = 178 K, as determined by thermodynamic measurements and neutron diffraction. Below T-1, Bi4Fe5O13F forms a fully ordered non-collinear antiferromagnetic structure, whereas the magnetic state between T-1 and T-N may be partially disordered according to the sizable increase in the magnetic entropy at T-1 and T-2. Bi4Fe5O13F reveals unanticipated magnetic transitions on the pentagonal Cairo spin lattice and calls for a further work on finite-temperature properties of this strongly frustrated spin model. DOI: 10.1103/PhysRevB.87.024423 |
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Wos |
000314224800002 |
Publication Date |
2013-02-01 |
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Series Editor |
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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 |
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Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
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Call Number |
UA @ lucian @ c:irua:107688 |
Serial |
1293 |
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Author |
Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H. |
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Title |
Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
82 |
Issue |
5 |
Pages |
054107,1-054107,12 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties. |
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Wos |
000280849400001 |
Publication Date |
2010-08-12 |
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ISSN |
1098-0121;1550-235X; |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:83991 |
Serial |
1706 |
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Author |
Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Turner, S.; Van Tendeloo, G. |
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Title |
Fabrication and Characterization of Fe2O3-Based Nanostructures Functionalized with Metal Particles and Oxide Overlayers |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of advanced microscopy research |
Abbreviated Journal |
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Volume |
10 |
Issue |
10 |
Pages |
239-243 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the design of nanosystems based on functionalized -Fe 2 O 3 nanostructures supported on fluorine-doped tin oxide (FTO) substrates. The target materials were developed by means of hybrid vapor phase approaches, combining plasma assisted-chemical vapor deposition (PA-CVD) for the production of iron(III) oxide systems and the subsequent radio frequency (RF)-sputtering or atomic layer deposition (ALD) for the functionalization with Au nanoparticles or TiO 2 overlayers, respectively. The interplay between material characteristics and the adopted processing parameters was investigated by complementary analytical techniques, encompassing X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), and energy dispersive X-ray spectroscopy (EDXS). The obtained results highlight the possibility of fabricating Au/ -Fe 2 O 3 nanocomposites, with a controlled dispersion and distribution of metal particles, and TiO 2 / -Fe 2 O 3 heterostructures, characterized by an intimate coupling between the constituent oxides. |
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Wos |
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Publication Date |
2015-12-01 |
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ISSN |
2156-7573 |
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Additional Links |
UA library record |
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Notes |
The authors acknowledge the financial support under the FP7 project “SOLARO- GENIX” (NMP4-SL-2012-310333), as well as Padova University ex-60% 2012–2015 projects, grant n CPDR132937/13 (SOLLEONE), and Regione Lombardia- INSTM ATLANTE program. Stuart Turner acknowledges the FWO Flanders for a post-doctoral scholarship. Thanks are also due to Dr. L. Borgese and Prof. E. Bontempi (Chemistry for Technologies Laboratory, Brescia Univer- sity, Italy) for precious assistance in ALD experiments. |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @ c:irua:132798 |
Serial |
4058 |
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| Permanent link to this record |
