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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 |
Becker, M.; Guzzinati, G.; Béché, A.; Verbeeck, J.; Batelaan, H. |
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Title |
Asymmetry and non-dispersivity in the Aharonov-Bohm effect |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
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Volume |
10 |
Issue |
10 |
Pages |
1700 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Decades ago, Aharonov and Bohm showed that electrons are affected by electromagnetic potentials in the absence of forces due to fields. Zeilinger's theorem describes this absence of classical force in quantum terms as the “dispersionless” nature of the Aharonov-Bohm effect. Shelankov predicted the presence of a quantum “force” for the same Aharonov-Bohm physical system as elucidated by Berry. Here, we report an experiment designed to test Shelankov's prediction and we provide a theoretical analysis that is intended to elucidate the relation between Shelankov's prediction and Zeilinger's theorem. The experiment consists of the Aharonov-Bohm physical system; free electrons pass a magnetized nanorod and far-field electron diffraction is observed. The diffraction pattern is asymmetric confirming one of Shelankov's predictions and giving indirect experimental evidence for the presence of a quantum “force”. Our theoretical analysis shows that Zeilinger's theorem and Shelankov's result are both special cases of one theorem. |
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Wos |
000464338100011 |
Publication Date |
2019-04-12 |
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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 |
2041-1723 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.124 |
Times cited |
12 |
Open Access |
OpenAccess |
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Notes |
; H.B. would like to thank Michael Berry for bringing the presence of a quantum “force” to our attention. A.B., G.G. and J.V. acknowledge support from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. G.G. acknowledges support from the Fonds Wetenschappelijk Onderzoek -Vlaanderen (FWO). M.B. and H.B. acknowledge support by the U.S. National Science Foundation under Grant No. 1602755. ; |
Approved |
Most recent IF: 12.124 |
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Call Number |
UA @ admin @ c:irua:159341 |
Serial |
5241 |
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Author |
Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. |
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Title |
Spectroscopic coincidence experiments in transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
114 |
Issue |
14 |
Pages |
143101 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We demonstrate the feasibility of coincidence measurements on a conventional transmission electron microscope, revealing the temporal
correlation between electron energy loss spectroscopy (EELS) and energy dispersive X-ray (EDX) spectroscopy events. We make use of a
delay line detector with ps-range time resolution attached to a modified EELS spectrometer. We demonstrate that coincidence between both
events, related to the excitation and deexcitation of atoms in a crystal, provides added information not present in the individual EELS or
EDX spectra. In particular, the method provides EELS with a significantly suppressed or even removed background, overcoming the many
difficulties with conventional parametric background fitting as it uses no assumptions on the shape of the background, requires no user input
and does not suffer from counting noise originating from the background signal. This is highly attractive, especially when low concentrations
of elements need to be detected in a matrix of other elements. |
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Wos |
000464450200022 |
Publication Date |
2019-04-08 |
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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 |
18 |
Open Access |
OpenAccess |
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Notes |
Fonds Wetenschappelijk Onderzoek, G093417 ; Horizon 2020 Framework Programme, 823717 ESTEEM3 ; Helmholtz Association, VH-NG-1327 ; |
Approved |
Most recent IF: 3.411 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:159155 |
Serial |
5168 |
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Author |
Charalampopoulou, E.; Cautaerts, N.; Van der Donck, T.; Schryvers, D.; Lambrinou, K.; Delville, R. |
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Title |
Orientation relationship of the austenite-to-ferrite transformation in austenitic stainless steels due to dissolution corrosion in contact with liquid Pb-Bi eutectic |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
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Volume |
167 |
Issue |
167 |
Pages |
66-70 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The orientation relationship of an austenite-to-ferrite phase transformation in 316L stainless steels induced by the loss of austenite stabilizers resulting from the steel dissolution corrosion in liquid Pb-Bi eutectic was studied by means of electron backscatter diffraction. The misorientations at the austenite/ferrite interface were compared to the prevailing orientation relationship models in steels. The Pitsch orientation relationship model was found to be predominant, which is unusual for austenite-to-ferrite bulk transformations in steels. The nature of this particular transformation, which involves loss of steel alloying elements and the presence of an interfacial liquid metal layer, is discussed to explain this finding. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
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Wos |
000468720000014 |
Publication Date |
2019-04-06 |
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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 |
1359-6462 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.747 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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Notes |
; The authors would like to thank J. Joris (SCK center dot CEN) for technical support during corrosion testing, J. Lim (SCK center dot CEN) for the manufacture and calibration of the oxygen sensors used in this work and W. Van Renterghem (SCK center dot CEN) for his valuable help with the EBSD measurements. The steel suppliers were: Industeel, ArcelorMittal Group, for the 316L-SA plate, and Panchmahal Steel Ltd., India, for the 316L-CWrod. The authors gratefully acknowledge the financial support provided within the framework of the ongoing development of the MYRRHA irradiation facility. The research leading to these results falls within the framework of the European Energy Research Alliance Joint Programme on Nuclear Materials (EERA JPNM). ; |
Approved |
Most recent IF: 3.747 |
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Call Number |
UA @ admin @ c:irua:160228 |
Serial |
5257 |
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Author |
Gonzalez-Rubio, G.; Kumar, V.; Llombart, P.; Diaz-Nunez, P.; Bladt, E.; Altantzis, T.; Bals, S.; Pena-Rodriguez, O.; Noya, E.G.; MacDowell, L.G.; Guerrero-Martinez, A.; Liz-Marzan, L.M. |
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Title |
Disconnecting Symmetry Breaking from Seeded Growth for the Reproducible Synthesis of High Quality Gold Nanorods |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume |
13 |
Issue |
13 |
Pages |
4424-4435 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
One of the major difficulties hindering the widespread application of colloidal anisotropic plasmonic nanoparticles is the limited robustness and reproducibility of multistep synthetic methods. We demonstrate herein that the reproducibility and reliability of colloidal gold nanorod (AuNR) synthesis can be greatly improved by disconnecting the symmetry-breaking event from the seeded growth process. We have used a modified silver-assisted seeded growth method in the presence of the surfactant hexadecyltrimethylammonium bromide and n-decanol as a co-surfactant to prepare small AuNRs in high yield, which were then used as seeds for the growth of high quality AuNR colloids. Whereas the use of n-decanol provides a more-rigid micellar system, the growth on anisotropic seeds avoids sources of irreproducibility during the symmetry breaking step, yielding uniform AuNR colloids with narrow plasmon bands, ranging from 600 to 1270 nm, and allowing the fine-tuning of the final dimensions. This method provides a robust route for the preparation of high quality AuNR colloids with tunable morphology, size, and optical response in a reproducible and scalable manner. |
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Wos |
000466052900067 |
Publication Date |
2019-04-02 |
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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 |
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 |
100 |
Open Access |
OpenAccess |
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Notes |
; This work has been funded by the Spanish MINECO (grant nos. FIS2017-89361-C3-2-P and MAT2017-86659-R), the Madrid Regional Government (grant no. P2018/NMT-4389) and the Complutense University of Madrid (grant no. PR75/18-21616). Funding is acknowledged from the European Commission (grant no. EUSMI 731019). G.G.-R. acknowledges receipt of FPI Fellowship from the Spanish MINECO. E.B. and T.A. acknowledge postdoctoral grants from the Research Foundation Flanders (FWO). The authors are indebted to Profs. Justin Gooding, Watson Loh, Nicholas Kotov, Deqing Zhang, Mihaela Delcea, Maurizio Prato, and Krishna Ganesh, for providing milli-Q water samples. ; |
Approved |
Most recent IF: 13.942 |
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Call Number |
UA @ admin @ c:irua:160417 |
Serial |
5246 |
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Author |
Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Batuk, M.; Hadermann, J.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. |
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Title |
Effect of zinc oxide modification by indium oxide on microstructure, adsorbed surface species, and sensitivity to CO |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Frontiers in materials |
Abbreviated Journal |
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Volume |
6 |
Issue |
6 |
Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Additives in semiconductor metal oxides are commonly used to improve sensing behavior of gas sensors. Due to complicated effects of additives on the materials microstructure, adsorption sites and reactivity to target gases the sensing mechanism with modified metal oxides is a matter of thorough research. Herein, we establish the promoting effect of nanocrystalline zinc oxide modification by 1-7 at.% of indium on the sensitivity to CO gas due to improved nanostructure dispersion and concentration of active sites. The sensing materials were synthesized via an aqueous coprecipitation route. Materials composition, particle size and BET area were evaluated using X-ray diffraction, nitrogen adsorption isotherms, high-resolution electron microscopy techniques and EDX-mapping. Surface species of chemisorbed oxygen, OH-groups, and acid sites were characterized by probe molecule techniques and infrared spectroscopy. It was found that particle size of zinc oxide decreased and the BET area increased with the amount of indium oxide. The additive was observed as amorphous indium oxide segregated on agglomerated ZnO nanocrystals. The measured concentration of surface species was higher on In2O3-modified zinc oxide. With the increase of indium oxide content, the sensor response of ZnO/In2O3 to CO was improved. Using in situ infrared spectroscopy, it was shown that oxidation of CO molecules was enhanced on the modified zinc oxide surface. The effect of modifier was attributed to promotion of surface OH-groups and enhancement of CO oxidation on the segregated indium ions, as suggested by DFT in previous work. |
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Wos |
000461540600001 |
Publication Date |
2019-03-15 |
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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 |
2296-8016 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
11 |
Open Access |
OpenAccess |
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Notes |
; Research was supported by the grant from Russian Science Foundation (project No. 18-73-00071). ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:158540 |
Serial |
5205 |
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Author |
Yin, C.; Krishnan, D.; Gauquelin, N.; Verbeeck, J.; Aarts, J. |
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Title |
Controlling the interfacial conductance in LaAlO3/SrTiO3 in 90 degrees off-axis sputter deposition |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
3 |
Issue |
3 |
Pages |
034002 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the fabrication of conducting interfaces between LaAlO3 and SrTiO3 by 90 degrees off-axis sputtering in an Ar atmosphere. At a growth pressure of 0.04 mbar the interface is metallic, with a carrier density of the order of 1 x 10(13) cm(-2) at 3 K. By increasing the growth pressure, we observe an increase of the out-of-plane lattice constants of the LaAlO3 films while the in-plane lattice constants do not change. Also, the low-temperature sheet resistance increases with increasing growth pressure, leading to an insulating interface when the growth pressure reaches 0.10 mbar. We attribute the structural variations to an increase of the La/Al ratio, which also explains the transition from metallic behavior to insulating behavior of the interfaces. Our research shows that the control which is furnished by the Ar pressure makes sputtering as versatile a process as pulsed laser deposition, and emphasizes the key role of the cation stoichiometry of LaAlO3 in the formation of the conducting interface. |
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Wos |
000461077100002 |
Publication Date |
2019-03-12 |
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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 |
2.926 |
Times cited |
4 |
Open Access |
Not_Open_Access |
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Notes |
; We thank Nikita Lebedev, Aymen Ben Hamida, and Prateek Kumar for useful discussions and Giordano Mattoni, Jun Wang, Vincent Joly, and Hozanna Miro for their technical assistance. We also thank Jean-Marc Triscone and his group for sharing their design of the sputtering system with us. This work is part of the FOM research programme DESCO with Project No. 149, which is (partly) financed by the Netherlands Organisation for Scientific Research (NWO). C.Y. is supported by China Scholarship Council (CSC) with Grant No. 201508110214. N.G., D.K., and J.V. acknowledge financial support from the GOA project “Solarpaint” of the University of Antwerp. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:158547 |
Serial |
5243 |
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Author |
Kim, Y.; Che, F.; Jo, J.W.; Choi, J.; de Arquer, F.P.G.; Voznyy, O.; Sun, B.; Kim, J.; Choi, M.-J.; Quintero-Bermudez, R.; Fan, F.; Tan, C.S.; Bladt, E.; Walters, G.; Proppe, A.H.; Zou, C.; Yuan, H.; Bals, S.; Hofkens, J.; Roeffaers, M.B.J.; Hoogland, S.; Sargent, E.H. |
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Title |
A Facet-Specific Quantum Dot Passivation Strategy for Colloid Management and Efficient Infrared Photovoltaics |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
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Volume |
31 |
Issue |
31 |
Pages |
1805580 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Colloidal nanocrystals combine size- and facet-dependent properties with solution processing. They offer thus a compelling suite of materials for technological applications. Their size- and facet-tunable features are studied in synthesis; however, to exploit their features in optoelectronic devices, it will be essential to translate control over size and facets from the colloid all the way to the film. Larger-diameter colloidal quantum dots (CQDs) offer the attractive possibility of harvesting infrared (IR) solar energy beyond absorption of silicon photovoltaics. These CQDs exhibit facets (nonpolar (100)) undisplayed in small-diameter CQDs; and the materials chemistry of smaller nanocrystals fails consequently to translate to materials for the short-wavelength IR regime. A new colloidal management strategy targeting the passivation of both (100) and (111) facets is demonstrated using distinct choices of cations and anions. The approach leads to narrow-bandgap CQDs with impressive colloidal stability and photoluminescence quantum yield. Photophysical studies confirm a reduction both in Stokes shift (approximate to 47 meV) and Urbach tail (approximate to 29 meV). This approach provides a approximate to 50% increase in the power conversion efficiency of IR photovoltaics compared to controls, and a approximate to 70% external quantum efficiency at their excitonic peak. |
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Wos |
000465600000001 |
Publication Date |
2019-03-12 |
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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 |
0935-9648 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
19.791 |
Times cited |
74 |
Open Access |
OpenAccess |
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Notes |
; Y.K., F.C., J.W.J., and J.C. contributed equally. This work was supported by King Abdullah University of Science and Technology (KAUST, Office of Sponsored Research (OSR), Award No. OSR-2017-CPF-3325) and Ontario Research Fund-Research Excellence program (ORF7-Ministry of Research and Innovation, Ontario Research Fund-Research Excellence Round 7). E.B. gratefully acknowledges financial support by the Research Foundation-Flanders (FWO Vlaanderen). Y.K. received financial support from the DGIST R&D Programs of the Ministry of Science, ICT & Future Planning of Korea (18-ET-01). M.B.J.R. and J.H. acknowledge financial support from the Research Foundation-Flanders (FWO, grants nr ZW15_09-GOH6316 and G.098319N) and the Flemish government through long-term structural funding Methusalem (CASAS2, Meth/15/04). H.Y. acknowledges the Research Foundation-Flanders (FWO) for a postdoctoral fellowship. The authors thank L. Levina, R. Wolowiec, D. Kopilovic, and E. Palmiano for their technical help over the course of this research. ; |
Approved |
Most recent IF: 19.791 |
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Call Number |
UA @ admin @ c:irua:160392 |
Serial |
5239 |
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Author |
Müller-Caspary, K.; Grieb, T.; Müßener, J.; Gauquelin, N.; Hille, P.; Schörmann, J.; Verbeeck, J.; Van Aert, S.; Eickhoff, M.; Rosenauer, A. |
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Title |
Electrical Polarization in AlN/GaN Nanodisks Measured by Momentum-Resolved 4D Scanning Transmission Electron Microscopy |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
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Volume |
122 |
Issue |
10 |
Pages |
106102 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report the mapping of polarization-induced internal electric fields in AlN/GaN nanowire heterostructures at unit cell resolution as a key for the correlation of optical and structural phenomena in semiconductor optoelectronics. Momentum-resolved aberration-corrected scanning transmission electron microscopy is employed as a new imaging mode that simultaneously provides four-dimensional data in real and reciprocal space. We demonstrate how internal mesoscale and atomic electric fields can be separated in an experiment, which is verified by comprehensive dynamical simulations of multiple electron scattering. A mean difference of 5.3 +- 1.5 MV/cm is found for the polarization-induced electric fields in AlN and GaN, being in accordance with dedicated simulations and photoluminescence measurements in previous publications. |
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Wos |
000461067700007 |
Publication Date |
2019-03-11 |
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Abbreviated Series Title |
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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 |
8.462 |
Times cited |
26 |
Open Access |
OpenAccess |
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| |
Notes |
The authors gratefully acknowledge the help of Natalie Claes for analyzing the EDX data. K. M.-C. acknowledges funding from the Initiative and Network Fund of the Helmholtz Association within the Helmholtz Young Investigator Group moreSTEM under Contract No. VHNG- 1317 at Forschungszentrum Jülich in Germany. The direct electron detector (Medipix3, Quantum Detectors) was funded by the Hercules fund from the Flemish Government. N. G. and J. V. acknowledge funding from the Geconcentreerde Onderzoekacties project Solarpaint of the University of Antwerp. T. G. and A. R. acknowledge support from the Deutsche Forschungsgemeinschaft (Germany) under Contract No. RO2057/8-3. This work also received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme (Contract No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0368.15N).; Helmholtz Association, VH-NG-1317 ; Forschungszentrum Jülich; Flemish Government; Universiteit Antwerpen; Deutsche Forschungsgemeinschaft, RO2057/8-3 ; H2020 European Research Council, 770887 ; Fonds Wetenschappelijk Onderzoek, G.0368.15N ; |
Approved |
Most recent IF: 8.462 |
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| |
Call Number |
UA @ lucian @UA @ admin @ c:irua:158120 |
Serial |
5157 |
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| Permanent link to this record |
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Author |
Bouwmeester, R.L.; de Hond, K.; Gauquelin, N.; Verbeeck, J.; Koster, G.; Brinkman, A. |
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| |
Title |
Stabilization of the perovskite phase in the Y-Bi-O system by using a BaBiO₃ buffer layer |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Physica status solidi: rapid research letters |
Abbreviated Journal |
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| |
Volume |
13 |
Issue |
7 |
Pages |
1800679 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
A topological insulating phase has theoretically been predicted for the thermodynamically unstable perovskite phase of YBiO3. Here, it is shown that the crystal structure of the Y-Bi-O system can be controlled by using a BaBiO3 buffer layer. The BaBiO3 film overcomes the large lattice mismatch of 12% with the SrTiO3 substrate by forming a rocksalt structure in between the two perovskite structures. Depositing an YBiO3 film directly on a SrTiO3 substrate gives a fluorite structure. However, when the Y-Bi-O system is deposited on top of the buffer layer with the correct crystal phase and comparable lattice constant, a single oriented perovskite structure with the expected lattice constants is observed. |
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Place of Publication |
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Language |
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Wos |
000477671800005 |
Publication Date |
2019-03-06 |
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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 |
1862-6254 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
11 |
Open Access |
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| |
Notes |
The work at the University of Twente is financially supported by NWO through a VICI grant. N.G. and J.V. acknowledge financial support from the GOA project “Solarpaint” of the University of Antwerp. The microscope used for this experiment has been partially financed by the Hercules Fund from the Flemish Government. L. Ding is acknowledge for his help with the GPA analysis. |
Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:181236 |
Serial |
6889 |
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| Permanent link to this record |
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Author |
Zhang, G.; Zhou, Y.; Korneychuk, S.; Samuely, T.; Liu, L.; May, P.W.; Xu, Z.; Onufriienko, O.; Zhang, X.; Verbeeck, J.; Samuely, P.; Moshchalkov, V.V.; Yang, Z.; Rubahn, H.-G. |
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Title |
Superconductor-insulator transition driven by pressure-tuned intergrain coupling in nanodiamond films |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Physical review materials |
Abbreviated Journal |
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| |
Volume |
3 |
Issue |
3 |
Pages |
034801 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the pressure-driven superconductor-insulator transition in heavily boron-doped nanodiamond films. By systematically increasing the pressure, we suppress the Josephson coupling between the superconducting nanodiamond grains. The diminished intergrain coupling gives rise to an overall insulating state in the films, which is interpreted in the framework of a parallel-series circuit model to be the result of bosonic insulators with preserved localized intragrain superconducting order parameters. Our investigation opens up perspectives for the application of high pressure in research on quantum confinement and coherence. Our data unveil the percolative nature of the electrical transport in nanodiamond films, and highlight the essential role of grain boundaries in determining the electronic properties of this material. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000460684600002 |
Publication Date |
2019-03-05 |
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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 |
2.926 |
Times cited |
5 |
Open Access |
Not_Open_Access |
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| |
Notes |
; Y.Z. and Z.Y. acknowledge support from the National Key Research and Development Program of China (Grants No. 2018YFA0305700 and No. 2016YFA0401804), the National Natural Science Foundation of China (Grants No. 11574323, No. 11704387, and No. U1632275), the Natural Science Foundation of Anhui Province (Grants No. 1708085QA19 and No. 1808085MA06), and the Director's Fund of Hefei Institutes of Physical Science, Chinese Academy of Sciences (YZJJ201621). J.V. and S.K. acknowledge funding from the GOA project “Solarpaint” of the University of Antwerp, and thank the FWO (Research Foundation-Flanders) for financial support under Contract No. G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. T.S., O.O., and P.S. are supported by APVV-0036-11, APVV-0605-14, VEGA 1/0409/15, VEGA 2/0149/16, and EU ERDF-ITMS 26220120005. L.L. acknowledges the financial support of a FWO postdoctoral research fellowship (12V4419N) and the KU Leuven C1 project OPTIPROBE (C14/16/ 063). ; |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ admin @ c:irua:158561 |
Serial |
5260 |
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| Permanent link to this record |
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Author |
Tonkikh, A.A.; Tsebro, V.I.; Obraztsova, E.A.; Rybkovskiy, D.V.; Orekhov, A.S.; Kondrashov, I.I.; Kauppinen, E.I.; Chuvilin, A.L.; Obraztsova, E.D. |
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Title |
Films of filled single-wall carbon nanotubes as a new material for high-performance air-sustainable transparent conductive electrodes operating in a wide spectral range |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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| |
Volume |
11 |
Issue |
14 |
Pages |
6755-6765 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In this paper we show the advantages of transparent high conductive films based on filled single-wall carbon nanotubes. The nanotubes with internal channels filled with acceptor molecules (copper chloride or iodine) form networks demonstrating significantly improved characteristics. Due to the charge transfer between the nanotubes and filler, the doped-nanotube films exhibit a drop in electrical sheet resistance of an order of magnitude together with a noticeable increase of film transparency in the visible and near-infrared spectral range. The thermoelectric power measurements show a significant improvement of air-stability of the nanotube network in the course of the filling procedure. For the nanotube films with an initial transparency of 87% at 514 nm and electrical sheet resistance of 862 Ohm sq(-1) we observed an improvement of transparency up to 91% and a decrease of sheet resistance down to 98 Ohm sq(-1). The combination of the nanotube synthesis technique and molecules for encapsulation has been optimized for applications in optoelectronics. |
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Place of Publication |
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Language |
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Wos |
000464454400024 |
Publication Date |
2019-03-05 |
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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 |
2040-3364 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
7.367 |
Times cited |
2 |
Open Access |
Not_Open_Access: Available from 06.09.2019
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Notes |
; The work was supported by the RFBR project 18-29-19113-mk, grant no. 311533 of Academy of Finland, Russian Federation President Program for young scientist MK-3140.2018.2. Also, the reported study was funded by RFBR and Moscow city Government according to the research project no. 19-32-70004. TEM measurements were performed with financial support from the Ministry of Science and Higher Education of the Russian Federation within the state assignment for the Federal Scientific Research Centre “Crystallography and Photonics” of the Russian Academy of Sciences. ; |
Approved |
Most recent IF: 7.367 |
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| |
Call Number |
UA @ admin @ c:irua:159339 |
Serial |
5249 |
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| Permanent link to this record |
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Author |
Kontogiannidou, E.; Karavasili, C.; Kouskoura, M.G.; Filippousi, M.; Van Tendeloo, G.; Andreadis, I.I.; Eleftheriadis, G.K.; Kontopoulou, I.; Markopoulou, C.K.; Bouropoulos, N.; Fatouros, D.G. |
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Title |
In vitro and ex vivo assessment of microporous Faujasite zeolite (NaX-FAU) as a carrier for the oral delivery of danazol |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of drug delivery science and technology |
Abbreviated Journal |
J Drug Deliv Sci Tec |
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Volume |
51 |
Issue |
51 |
Pages |
177-184 |
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| |
Keywords |
A1 Journal article; Pharmacology. Therapy; Electron microscopy for materials research (EMAT) |
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Abstract |
Microporous zeolite NaX-FAU has been systemically evaluated for the oral delivery of the poorly water-soluble compound danazol. For this purpose, danazol-loaded zeolitic particles were prepared by the incipient wetness method and were characterized by means of N-2 physisorption, X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and high-resolution transmission electron microscopy (HRTEM). The zeolitic formulation shows a high drug payload and drug stability over a period of six months under accelerated storage conditions. The dissolution profile of danazol-loaded zeolitic particles was assessed in simulated gastric fluid (SGF) pH 1.2; fasted state simulated intestinal fluids (FaSSIF) and fed state simulated intestinal fluid (FeSSIF) showing a gradual and increasing drug dissolution in the different media. Ex vivo studies using the everted gut sac model show an increased drug transport across rat intestinal epithelium when loaded in the zeolitic particles. Our results suggest that microporous Faujasite zeolite (NaX-FAU) could be used as a drug delivery system to facilitate the oral delivery of poorly water soluble compounds. |
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Corporate Author |
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Place of Publication |
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Editor |
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Wos |
000468750300018 |
Publication Date |
2019-03-04 |
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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 |
1773-2247; 2588-8943 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.194 |
Times cited |
3 |
Open Access |
Not_Open_Access: Available from 27.08.2020
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Notes |
; This research was supported by General Secretariat for Research and Technology, Greece – Research Program “Excellence II, 4766”. The authors acknowledge financial support from the European Union under the Seventh Framework Program (Integrated Infrastructure Initiative No. 262348 European Soft Matter Infrastructure, ESMI). ; |
Approved |
Most recent IF: 1.194 |
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Call Number |
UA @ admin @ c:irua:160279 |
Serial |
5252 |
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Author |
Akkerman, Q.A.; Bladt, E.; Petralanda, U.; Dang, Z.; Sartori, E.; Baranov, D.; Abdelhady, A.L.; Infante, I.; Bals, S.; Manna, L. |
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Title |
Fully inorganic Ruddlesden-Popper double CI-I and triple CI-Br-I lead halide perovskite nanocrystals |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
31 |
Issue |
31 |
Pages |
2182-2190 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The vast majority of lead halide perovskite (LHP) nanocrystals (NCs) are currently based on either a single halide composition (CsPbCl3, CsPbBr3, and CsPbI3) or an alloyed mixture of bromide with either Cl- or I- [i.e., CsPb(Br:Cl)(3) or CsPb(Br:I)(3)]. In this work, we present the synthesis as well as a detailed optical and structural study of two halide alloying cases that have not previously been reported for LHP NCs: Cs2PbI2Cl2 NCs and triple halide CsPb(Cl:Br:I)(3) NCs. In the case of Cs2PbI2Cl2, we observe for the first time NCs with a fully inorganic Ruddlesden-Popper phase (RPP) crystal structure. Unlike the well-explored organic-inorganic RPP, here, the RPP formation is triggered by the size difference between the halide ions. These NCs exhibit a strong excitonic absorption, albeit with a weak photoluminescence quantum yield (PLQY). In the case of the triple halide CsPb(Cl:Br:I)(3) composition, the NCs comprise a CsPbBr2Cl perovskite crystal lattice with only a small amount of incorporated iodide, which segregates at RPP planes' interfaces within the CsPb(Cl:Br:I)(3) NCs. Supported by density functional theory calculations and postsynthetic surface treatments to enhance the PLQY, we show that the combination of iodide segregation and defective RPP interfaces are most likely linked to the strong PL quenching observed in these nanostructures. In summary, this work demonstrates the limits of halide alloying in LHP NCs because a mixture that contains halide ions of very different sizes leads to the formation of defective RPP interfaces and a severe quenching of LHP NC's optical properties. |
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Corporate Author |
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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 |
000462950400038 |
Publication Date |
2019-03-04 |
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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 |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
58 |
Open Access |
OpenAccess |
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Notes |
; Q.A.A. and L.M. acknowledge funding from the European Union Seventh Framework Programme under grant agreement no. 614897 (ERC Consolidator Grant “TRANS-NANO”). The work of D.B. was supported by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 794560. E.B. and S.B. acknowledge funding from the Research Foundation Flanders (G.038116N, G.03691, and funding of a postdoctoral grant to E.B.). I.I. acknowledges The Netherlands Organization of Scientific Research (NWO) for financial support through the Innovational Research Incentive (Vidi) Scheme (grant no. 723.013.002). The computational work was carried out on the Dutch national e-infrastructure with the support of the SURF Cooperative. ; |
Approved |
Most recent IF: 9.466 |
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Call Number |
UA @ admin @ c:irua:159414 |
Serial |
5250 |
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Author |
Chin, C.–M.; Battle, P.D.; Hunter, E.C.; Avdeev, M.; Hendrickx, M.; Hadermann, J. |
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Title |
Magnetic properties of La3Ni2Sb Ta Nb1––O9; from relaxor to spin glass |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of solid state chemistry (Print) |
Abbreviated Journal |
Journal of Solid State Chemistry |
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Volume |
273 |
Issue |
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Pages |
175-185 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Neutron diffraction experiments conducted at 5 K in a magnetic field 0 < H/kOe < 50 have shown that the monoclinic perovskite La3Ni2TaO9 behaves as a relaxor ferromagnet. Compositions in the series La3Ni2SbxTayNb1–x–yO9 have been synthesized in polycrystalline form. Electron microscopy, X–ray diffraction and neutron diffraction have shown that the solid solutions are largely homogeneous and monophasic. Magnetometry and neutron diffraction have shown that the relaxor magnetisation persists in low fields when x + y = 1 but is rapidly diminished by the introduction of niobium. This change in magnetic behaviour is ascribed to the differences in the d–orbital energies of Sb5+, Nb5+ and Ta5+. |
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Wos |
000466261100026 |
Publication Date |
2019-03-02 |
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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 |
0022-4596 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
|
Open Access |
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Notes |
We thank EPSRC for funding through grant EP/M0189541. CMC thanks the Croucher Foundation and the University of Oxford for the award of a graduate scholarship. |
Approved |
no |
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Call Number |
EMAT @ emat @c:irua:166445 |
Serial |
6346 |
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Author |
Yuan, S.; Pu, Z.; Zhou, H.; Yu, J.; Amiinu, I.S.; Zhu, J.; Liang, Q.; Yang, J.; He, D.; Hu, Z.; Van Tendeloo, G.; Mu, S. |
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Title |
A universal synthesis strategy for single atom dispersed cobalt/metal clusters heterostructure boosting hydrogen evolution catalysis at all pH values |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Nano energy |
Abbreviated Journal |
Nano Energy |
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Volume |
59 |
Issue |
59 |
Pages |
472-480 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The development of a stable, efficient and economic catalyst for hydrogen evolution reaction (HER) of water splitting is one of the most hopeful approaches to confront the environmental and energy crisis. A two-step method is employed to obtain metal clusters (Ru, N, Pd etc.) combining single cobalt atoms anchored on nitrogen-doped carbon (Ru/Pt/Pd@Co-SAs/N-C). Based on the synergistic effect between Ru clusters and single cobalt atoms, Ru@Co-SAs/N-C exhibits an outstanding HER electrocatalytic activity. Specifically, Ru@Co-SAs/N-C only needs 7 mV overpotential at 10 mA cm(-2) in 1 M KOH solution, which is much better than commercial 20 wt% PVC (40 mV) catalyst. Density functional theory (DFT) calculations further reveal the synergy effect between surface Ru nanoclusters and Co-SAs/N-C toward hydrogen adsorption for HER. Additionally, Ru@CoSAs/N-C also exhibits excellent catalytic ability and durability under acidic and neutral media. The present study opens a new avenue towards the design of metal clusters/single cobalt atoms heterostructures with outstanding performance toward HER and beyond. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000463032200051 |
Publication Date |
2019-02-25 |
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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 |
2211-2855 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.343 |
Times cited |
33 |
Open Access |
Not_Open_Access: Available from 01.11.2019
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Notes |
; S.Y., Z.P. and H.Z. contributed equally to this work. This work was financed by the National Natural Science Foundation of China (Grant No. 51372186, 51672204, 51701146) and the Fundamental Research Funds for the Central Universities (WUT: 2017III055, 2018III039GX, 2018IVA095). We express heartfelt thanks to Prof. Gaoke Zhang for the supply of computational resources in the School of Resources and Environmental Engineering, Wuhan University of Technology. ; |
Approved |
Most recent IF: 12.343 |
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Call Number |
UA @ admin @ c:irua:159330 |
Serial |
5240 |
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Author |
Cassidy, S.J.; Pitcher, M.J.; Lim, J.J.K.; Hadermann, J.; Allen, J.P.; Watson, G.W.; Britto, S.; Chong, E.J.; Free, D.G.; Grey, C.P.; Clarke, S.J. |
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Title |
Layered CeSO and LiCeSO oxide chalcogenides obtained via topotactic oxidative and reductive transformations |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
58 |
Issue |
6 |
Pages |
3838-3850 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The chemical accessibility of the Celv oxidation state enables redox chemistry to be performed on the naturally coinagemetal -deficient phases CeM1-xSO (M = Cu, Ag). A metastable black compound with the PbFC1 structure type (space group P4/nmm: a = 3.8396(1) angstrom, c = 6.607(4) angstrom, V = 97.40(6) angstrom(3)) and a composition approaching CeSO is obtained by deintercalation of Ag from CeAg0.8SO. High-resolution transmission electron microscopy reveals the presence of large defect-free regions in CeSO, but stacking faults are also evident which can be incorporated into a quantitative model to account for the severe peak anisotropy evident in all the highresolution X-ray and neutron diffractograms of bulk CeSO samples; these suggest that a few percent of residual Ag remains. A strawcolored compound with the filled PbFCI (i.e., ZrSiCuAs- or HfCuSi2type) structure (space group P4/nmm: a = 3.98171(1) angstrom, c = 8.70913(5) angstrom, V = 138.075(1) angstrom 3) and a composition close to LiCeSO, but with small amounts of residual Ag, is obtained by direct reductive lithiation of CeAga8S0 or by insertion of Li into CeSO using chemical or electrochemical means. Computation of the band structure of pure, stoichiometric CeSO predicts it to be a Ce' compound with the 4f-states lying approximately 1 eV above the sulfide-dominated valence band maximum. Accordingly, the effective magnetic moment per Ce ion measured in the CeSO samples is much reduced from the value found for the Ce3+-containing LiCeSO, and the residual paramagnetism corresponds to the Ce3+ ions remaining due to the presence of residual Ag, which presumably reflects the difficulty of stabilizing Ce' in the presence of sulfide (S2-). Comparison of the behavior of CeCu0.8SO with that of CeCu0.8SO reveals much slower reaction kinetics associated with the Cu,_xS layers, and this enables intermediate CeCui LixSO phases to be isolated. |
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Place of Publication |
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Language |
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Wos |
000461978700036 |
Publication Date |
2019-02-25 |
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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 |
0020-1669 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
; We thank the UK EPSRC (EP/M020517/1 and EP/P018874/1), the Leverhulme Trust (RPG-2014-221), and Science Foundation Ireland (Grant 12/IA/1414) for funding and the EPSRC for additional studentship support. We acknowledge the ISIS pulsed neutron and muon source and the Diamond Light Source Ltd. (EE13284 and EE18786) and the ESRF for the award of beam time. We thank Dr. R I. Smith for assistance on the neutron beamlines, Dr. A. Baker and Dr. C. Murray for support on III, and Dr. C. Curls for support on ID31. ; |
Approved |
Most recent IF: 4.857 |
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| |
Call Number |
UA @ admin @ c:irua:159426 |
Serial |
5253 |
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| Permanent link to this record |
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Author |
Queralto, A.; Graf, D.; Frohnhoven, R.; Fischer, T.; Vanrompay, H.; Bals, S.; Bartasyte, A.; Mathur, S. |
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Title |
LaFeO3 nanofibers for high detection of sulfur-containing gases |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
ACS Sustainable Chemistry and Engineering |
Abbreviated Journal |
Acs Sustain Chem Eng |
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| |
Volume |
7 |
Issue |
7 |
Pages |
6023-6032 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Lanthanum ferrite nanofibers were electrospun from a chemical sol and calcined at 600 degrees C to obtain singlephase LaFeO3 (LFO) perovskite. High-resolution transmission electron microscopy in conjunction with 3D tomographic analysis confirmed an interwoven network of hollow and porous (surface) LFO nanofibers. Owing to their high surface area and p-type behavior, the nanofiber meshes showed high chemoselectivity toward reducing toxic gases (SO2, H2S) that could be reproducibly detected at very low concentrations (<1 ppm), well below the threshold values for occupational safety and health. An increased sensitivity was observed in the temperature range of 150-300 degrees C with maximum sensor response at 250 degrees C. The surface reaction at the heterogeneous solid (LFO)/gas (SO2) interface that confirmed the formation of La-2(SO4)(3) was investigated by X-ray photoelectron spectroscopy. Moreover, the LFO fibers showed a high selectivity in the detection of oxidizing and reducing gases. Whereas superior detection of NH3 and H2S was measured, little response was observed for CO and NO2. Finally, the integration of nanowire meshes in commercial sensor platforms was successfully demonstrated. |
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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 |
000461978200047 |
Publication Date |
2019-02-21 |
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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 |
2168-0485 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.951 |
Times cited |
41 |
Open Access |
OpenAccess |
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Notes |
; The authors kindly acknowledge the ERA.Net RUS Plus project FONSENS funded by the German Federal Ministry of Education and Research (BMBF) under the grant no. 01DJ16017. A.Q. highly appreciates the support of the Alexander von Humboldt Foundation (grant no. AVH 1184642) and the BMBF for his postdoctoral fellowship. A.Q., D.G., R.F., T.F., and S.M. also kindly acknowledge the financial support of the University of Cologne. H.V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS). We also express our gratitude to Prof. Dr. J. Hadermann from the Electron Microscopy for Materials Science group at the University of Antwerp for her assistance. A.B. is grateful for the EUR EIPHI program (grant no. ANR-17-EURE-0002). ; |
Approved |
Most recent IF: 5.951 |
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| |
Call Number |
UA @ admin @ c:irua:158535 |
Serial |
5263 |
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| Permanent link to this record |
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Author |
Bercx, M.; Slap, L.; Partoens, B.; Lamoen, D. |
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| |
Title |
First-Principles Investigation of the Stability of the Oxygen Framework of Li-Rich Battery Cathodes |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
MRS advances |
Abbreviated Journal |
MRS Adv. |
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| |
Volume |
4 |
Issue |
14 |
Pages |
813-820 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Lithium-rich layered oxides such as Li<sub>2</sub>MnO<sub>3</sub>have shown great potential as cathodes in Li-ion batteries, mainly because of their large capacities. However, these materials still suffer from structural degradation as the battery is cycled, reducing the average voltage and capacity of the cell. The voltage fade is believed to be related to the migration of transition metals into the lithium layer, linked to the formation of O-O dimers with a short bond length, which in turn is driven by the presence of oxygen holes due to the participation of oxygen in the redox process. We investigate the formation of O-O dimers for partially charged O1-Li<sub>2</sub>MnO<sub>3</sub>using a first-principles density functional theory approach by calculating the reaction energy and kinetic barriers for dimer formation. Next, we perform similar calculations for partially charged O1-Li<sub>2</sub>IrO<sub>3</sub>, a Li-rich material for which the voltage fade was not observed during cycling. When we compare the stability of the oxygen framework, we conclude that the formation of O-O dimers is both thermodynamically and kinetically viable for O1-Li<sub>0.5</sub>MnO<sub>3</sub>. For O1-Li<sub>0.5</sub>IrO<sub>3</sub>, we observe that the oxygen lattice is much more stable, either returning to its original state when perturbed, or resulting in a structure with an O-O dimer that is much higher in energy. This can be explained by the mixed redox process for Li<sub>2</sub>IrO<sub>3</sub>, which is also shown from the calculated magnetic moments. The lack of O-O dimer formation in O1-Li<sub>0.5</sub>IrO<sub>3</sub>provides valuable insight as to why Li<sub>2</sub>IrO<sub>3</sub>does not demonstrate a voltage fade as the battery is cycled, which can be used to design Li-rich battery cathodes with an improved cycling performance. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000466846700004 |
Publication Date |
2019-02-21 |
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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 |
2059-8521 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
3 |
Open Access |
Not_Open_Access: Available from 22.02.2020
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Notes |
We acknowledge the financial support of FWO-Vlaanderen through project G040116N. 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 the FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: NA |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:160121 |
Serial |
5179 |
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| Permanent link to this record |
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Author |
Tan, X.; Stephens, P.W.; Hendrickx, M.; Hadermann, J.; Segre, C.U.; Croft, M.; Kang, C.-J.; Deng, Z.; Lapidus, S.H.; Kim, S.W.; Jin, C.; Kotliar, G.; Greenblatt, M. |
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Title |
Tetragonal Cs1.17In0.81Cl3 : a charge-ordered indium halide perovskite derivative |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
31 |
Issue |
6 |
Pages |
1981-1989 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Polycrystalline samples of Cs1.17In0.81Cl3 were prepared by annealing a mixture of CsCl, InCl, and InCl3, stoichiometric for the targeted CsInCl3. Synchrotron powder X-ray diffraction refinement and chemical analysis by energy dispersive X-ray indicated that Cs1.17In0.81Cl3, a tetragonal distorted perovskite derivative (I4/m), is the thermodynamically stable product. The refined unit cell parameters and space group were confirmed by electron diffraction. In the tetragonal structure, In+ and In3+ are located in four different crystallographic sites, consistent with their corresponding bond lengths. In1, In2, and In3 are octahedrally coordinated, whereas In4 is at the center of a pentagonal bipyramid of Cl because of the noncooperative octahedral tilting of In4Cl6. The charged-ordered In+ and In3+ were also confirmed by X-ray absorption and Raman spectroscopy. Cs1.17In0.81Cl3 is the first example of an inorganic halide double perovskite derivative with charged-ordered In+ and In3+. Band structure and optical conductivity calculations were carried out with both generalized gradient approximation (GGA) and modified Becke-Johnson (mBJ) approach; the GGA calculations estimated the band gap and optical band gap to be 2.27 eV and 2.4 eV, respectively. The large and indirect band gap suggests that Cs1.17In0.81Cl3 is not a good candidate for photovoltaic application. |
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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 |
000462950400017 |
Publication Date |
2019-02-19 |
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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 |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
OpenAccess |
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Notes |
; M.G. and X.T. were supported by the Center for Computational Design of Functional Strongly Correlated Materials and Theoretical Spectroscopy under DOE Grant No. DE-FOA-0001276. M.G. also acknowledges support of NSF-DMR-1507252 grant. G.K. and C.-J.K. were supported by the Air Force Office of Scientific Research. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. The use of the Advanced Photon Source at the Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The works at IOPCAS were supported by NSF & MOST of China through research projects. ; |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
UA @ admin @ c:irua:159413 |
Serial |
5262 |
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Author |
Van Velthoven, N.; Waitschat, S.; Chavan, S.M.; Liu, P.; Smolders, S.; Vercammen, J.; Bueken, B.; Bals, S.; Lillerud, K.P.; Stock, N.; De Vos, D.E. |
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Title |
Single-site metal-organic framework catalysts for the oxidative coupling of arenes via C-H/C-H activation |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
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| |
Volume |
10 |
Issue |
10 |
Pages |
3616-3622 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
C-H activation reactions are generally associated with relatively low turnover numbers (TONs) and high catalyst concentrations due to a combination of low catalyst stability and activity, highlighting the need for recyclable heterogeneous catalysts with stable single-atom active sites. In this work, several palladium loaded metal-organic frameworks (MOFs) were tested as single-site catalysts for the oxidative coupling of arenes (e.g. o-xylene) via C-H/C-H activation. Isolation of the palladium active sites on the MOF supports reduced Pd(0) aggregate formation and thus catalyst deactivation, resulting in higher turnover numbers (TONs) compared to the homogeneous benchmark reaction. Notably, a threefold higher TON could be achieved for palladium loaded MOF-808 due to increased catalyst stability and the heterogeneous catalyst could efficiently be reused, resulting in a cumulative TON of 1218 after three runs. Additionally, the palladium single-atom active sites on MOF-808 were successfully identified by Fourier transform infrared (FTIR) and extended X-ray absorption fine structure (EXAFS) spectroscopy. |
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Corporate Author |
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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 |
000463759100017 |
Publication Date |
2019-02-18 |
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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 |
2041-6520 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.668 |
Times cited |
68 |
Open Access |
OpenAccess |
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Notes |
; The research leading to these results has received funding from the NMBP-01-2016 Program of the European Union's Horizon 2020 Framework Program H2020/2014-2020/under grant agreement no. [720996]. N. V. V., S. S., J. V., B. B. and D. E. D. V. thank the FWO for funding (SB, Aspirant and postdoctoral grants). The electron microscopy work was supported by FWO funding G038116. D. E. D. V. is grateful for KU Leuven support in the frame of the CASAS Metusalem project and a C3 type project. The XAS experiments were performed on beamline BM26A at the European Synchrotron Radiation Facility (ESRF), Grenoble, France. We are grateful to D. Banerjee at the ESRF for providing assistance in using beamline BM26A. Johnson Matthey and S. Bennett are gratefully acknowledged for providing Smopex-102. ; |
Approved |
Most recent IF: 8.668 |
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| |
Call Number |
UA @ admin @ c:irua:159403 |
Serial |
5259 |
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Author |
Mourdikoudis, S.; Montes-Garcia, V.; Rodal-Cedeira, S.; Winckelmans, N.; Perez-Juste, I.; Wu, H.; Bals, S.; Perez-Juste, J.; Pastoriza-Santos, I. |
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Title |
Highly porous palladium nanodendrites : wet-chemical synthesis, electron tomography and catalytic activity |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
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| |
Volume |
48 |
Issue |
48 |
Pages |
3758-3767 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A simple procedure to obtain highly porous hydrophilic palladium nanodendrites in one-step is described. The synthetic strategy is based on the thermal reduction of a Pd precursor in the presence of a positively charged polyelectrolyte such as polyethylenimine (PEI). Advanced electron microscopy techniques combined with X-ray diffraction (XRD), thermogravimetry and BET analysis demonstrate the polycrystalline nature of the nanodendrites as well as their high porosity and active surface area, facilitating a better understanding of their unique morphology. Besides, catalytic studies performed using Raman scattering and UV-Vis spectroscopies revealed that the nanodendrites exhibit a superior performance as recyclable catalysts towards hydrogenation reaction compared to other noble metal nanoparticles. |
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Place of Publication |
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Wos |
000461088700027 |
Publication Date |
2019-02-18 |
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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 |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
23 |
Open Access |
OpenAccess |
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Notes |
; This work was supported by the Ministerio de Economia y Competitividad (MINECO, Spain) under the Grant MAT2016-77809-R, Xunta de Galicia (GRC ED431C 2016-048 and Centro Singular de Investigacion de Galicia (ED431G/02)) and Fundacion Ramon Areces (SERSforSafety). S. M. acknowledges funding from the General Secretariat for Research and Technology in Greece (Project PE4 (1546)). S. B. and N. W. acknowledge financial support by the European Research Council (ERC Starting Grant #335078-COLOURATOMS). We thank the EPSRC CNIE Research Facility (EPSRC Award, EP/K038656/1) at the University College London for the collection of the BET data. Authors thank J. Millos for the XRD measurements. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:158530 |
Serial |
5251 |
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Author |
Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q. |
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Title |
Study of the Q′ (Q)-phase precipitation in Al–Mg–Si–Cu alloys by quantification of atomic-resolution transmission electron microscopy images and atom probe tomography |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Journal of materials science |
Abbreviated Journal |
J Mater Sci |
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Volume |
54 |
Issue |
10 |
Pages |
7943-7952 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The precipitation mechanism of the Q phase in Al-Mg-Si-Cu alloys has long been the subject of ambiguity and debate since its metastable phase (Q 0) has the same crystal structure and similar lattice parameters as its equilibrium counterparts. In the present work, the evolution of the Q 0 (Q) phase during aging is studied by combination of quantitative atomic-resolution scanning transmission electron microscopy and atom probe tomography. It was found that the transformation from the Q 0 to the Q phase involves changes of the occupancy of Al atoms in atomic columns of the Q 0 (Q) phase. The Al atoms incorporated in the Cu, Si and Mg columns are gradually released into the Al matrix, while mixing between Cu and Si atoms occurs in the Si columns. This transformation process is mainly attributed to the low lattice misfit of the equilibrium Q phase. Besides, the formation of various compositions of the Q phase is due to the different occupancy in the atomic columns of the Q phase. The occupancy changes in the columns of the Q phase are kinetically controlled and are strongly influenced by the alloy composition and aging temperature. |
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Place of Publication |
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Language |
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Wos |
000460069500043 |
Publication Date |
2019-02-14 |
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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 |
0022-2461 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.599 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing, cstc2017zdcy-zdzxX0006 ; Fundamental Research Funds for the Central Universities of China, 2018CDGFCL0002 106112017CDJQJ308822 ; Belgian National Fund for Scientific Research; the National Natural Science Foundation of China, 51871035 ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant No. cstc2017zdcyzdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDGFCL0002), the National Natural Science Foundation of China (Grant No. 51871035) and the Foundation for Innovative Research Groups J Mater Sci National Natural Science Foundation of China (Grant No. 51421001). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). |
Approved |
Most recent IF: 2.599 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:158112 |
Serial |
5158 |
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Author |
Van Aert, S.; De Backer, A.; Jones, L.; Martinez, G.T.; Béché, A.; Nellist, P.D. |
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Title |
Control of Knock-On Damage for 3D Atomic Scale Quantification of Nanostructures: Making Every Electron Count in Scanning Transmission Electron Microscopy |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
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Volume |
122 |
Issue |
6 |
Pages |
066101 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Understanding nanostructures down to the atomic level is the key to optimizing the design of advancedmaterials with revolutionary novel properties. This requires characterization methods capable of quantifying the three-dimensional (3D) atomic structure with the highest possible precision. A successful approach to reach this goal is to count the number of atoms in each atomic column from 2D annular dark field scanning transmission electron microscopy images. To count atoms with single atom sensitivity, a minimum electron dose has been shown to be necessary, while on the other hand beam damage, induced by the high energy electrons, puts a limit on the tolerable dose. An important challenge is therefore to develop experimental strategies to optimize the electron dose by balancing atom-counting fidelity vs the risk of knock-on damage. To achieve this goal, a statistical framework combined with physics-based modeling of the dose-dependent processes is here proposed and experimentally verified. This model enables an investigator to theoretically predict, in advance of an experimental measurement, the optimal electron dose resulting in an unambiguous quantification of nanostructures in their native state with the highest attainable precision. |
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Place of Publication |
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Language |
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Wos |
000458824200008 |
Publication Date |
2019-02-13 |
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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 |
8.462 |
Times cited |
3 |
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). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (WO.010.16N, G.0934.17N, G.0502.18N, G.0267.18N), and a grant to A. D. B. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement No. 312483— ESTEEM2 (Integrated Infrastructure Initiative-I3) and the UK EPSRC (Grant No. EP/M010708/1). |
Approved |
Most recent IF: 8.462 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:157175 |
Serial |
5156 |
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Author |
Scarabelli, L.; Schumacher, M.; Jimenez de Aberasturi, D.; Merkl, J.‐P.; Henriksen‐Lacey, M.; Milagres de Oliveira, T.; Janschel, M.; Schmidtke, C.; Bals, S.; Weller, H.; Liz‐Marzán, L.M. |
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Title |
Encapsulation of Noble Metal Nanoparticles through Seeded Emulsion Polymerization as Highly Stable Plasmonic Systems |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
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Volume |
29 |
Issue |
29 |
Pages |
1809071 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The implementation of plasmonic nanoparticles in vivo remains hindered by important limitations such as biocompatibility, solubility in biological fluids, and physiological stability. A general and versatile protocol is presented, based on seeded emulsion polymerization, for the controlled encapsulation of gold and silver nanoparticles. This procedure enables the encapsulation of single nanoparticles as well as nanoparticle clusters inside a protecting polymer shell. Specifically, the efficient coating of nanoparticles of both metals is demonstrated, with final dimensions ranging between 50 and 200 nm, i.e., sizes of interest for bio-applications. Such hybrid nanocomposites display extraordinary stability in high ionic strength and oxidizing environments, along with high cellular uptake, and low cytotoxicity. Overall, the prepared nanostructures are promising candidates for plasmonic applications under biologically relevant conditions. |
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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 |
000467109100024 |
Publication Date |
2019-02-11 |
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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 |
1616-301X |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
12.124 |
Times cited |
19 |
Open Access |
OpenAccess |
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Notes |
L.S. and M.S. contributed equally to this work. This work was supported by the Spanish MINECO (Grant MAT2017-86659-R), by the German Research Foundation (DFG, Grant LA 2901/1-1) and by the European Research Council (Grant 335078 COLOURATOM to S.B). The authors acknowledge funding from the European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M). L.S. acknowledges funding from the American-Italian Cancer Foundation through a Post-Doctoral Research Fellowship. D.J.d.A. thanks MINECO for a Juan de la Cierva fellowship (IJCI-2015-24264). J.P.M. was financed by Verband der Chemischen Industrie e.V. (VCI). The authors thank Dr. Artur Feld, Dr. Andreas Kornowski and Stefan Werner (Institute of Physical Chemistry, University of Hamburg) for their support. |
Approved |
Most recent IF: 12.124 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:160710 |
Serial |
5190 |
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| Permanent link to this record |
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Author |
Bercx, M.; Partoens, B.; Lamoen, D. |
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Title |
Quantitative modeling of secondary electron emission from slow-ion bombardment on semiconductors |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
99 |
Issue |
8 |
Pages |
085413 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
When slow ions incident on a surface are neutralized, the excess potential energy is passed on to an electron inside the surface, leading to emission of secondary electrons. The microscopic description of this process, as
well as the calculation of the secondary electron yield, is a challenging problem due to its complexity as well
as its sensitivity to surface properties. One of the first quantitative descriptions was articulated in the 1950s by
Hagstrum, who based his calculation on a parametrization of the density of states of the material. In this paper, we
present a model for calculating the secondary electron yield, derived from Hagstrum’s initial approach. We use
first-principles density functional theory calculations to acquire the necessary input and introduce the concept of
electron cascades to Hagstrum’s model in order to improve the calculated spectra, as well as remove its reliance
on fitting parameters. We apply our model to He+ and Ne+ ions incident on Ge(111) and Si(111) and obtain
yield spectra that match closely to the experimental results of Hagstrum. |
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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 |
000458367800010 |
Publication Date |
2019-02-11 |
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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 |
2469-9950 |
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 |
5 |
Open Access |
OpenAccess |
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Notes |
We would like to thank Prof. D. Depla for the useful discussions on the secondary electron yield. Furthermore, we acknowledge financial support of FWO-Vlaanderen through project G.0216.14N. 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 the FWOVlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 3.836 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:157174 |
Serial |
5154 |
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| Permanent link to this record |
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Author |
Keunecke, M.; Lyzwa, F.; Schwarzbach, D.; Roddatis, V.; Gauquelin, N.; Müller-Caspary, K.; Verbeeck, J.; Callori, S.J.; Klose, F.; Jungbauer, M.; Moshnyaga, V. |
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Title |
High-TCInterfacial Ferromagnetism in SrMnO3/LaMnO3Superlattices |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv. Funct. Mater. |
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Volume |
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Issue |
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Pages |
1808270 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Heterostructures of strongly correlated oxides demonstrate various intriguing and potentially useful interfacial phenomena. LaMnO3/SrMnO3 superlattices are presented showcasing a new high‐temperature ferromagnetic phase with Curie temperature, TC ≈360 K, caused by electron transfer from the surface of the LaMnO3 donor layer into the neighboring SrMnO3 acceptor layer. As a result, the SrMnO3 (top)/LaMnO3 (bottom) interface shows an enhancement of the magnetization as depth‐profiled by polarized neutron reflectometry. The length scale of charge transfer, λTF ≈2 unit cells, is obtained from in situ growth monitoring by optical ellipsometry, supported by optical simulations, and further confirmed by high resolution electron microscopy and spectroscopy. A model of the inhomogeneous distribution of electron density in LaMnO3/SrMnO3 layers along the growth direction is concluded to account for a complex interplay between ferromagnetic and antiferromagnetic layers in superlattices. |
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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 |
000535358900008 |
Publication Date |
2019-02-10 |
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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 |
1616301X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15.621 |
Times cited |
26 |
Open Access |
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Notes |
The authors thank EU FP7 Framework (Project IFOX) and DFG (SFB 1073, TP B04, A02, Z02) for the financial support. J.V., K.M.C and N.G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge ordering). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. The PNR experiment was funded by the Australian Nuclear Science and Technology Organization (proposal number P3985). |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:162108 |
Serial |
5294 |
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| Permanent link to this record |
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Author |
Leuthner, G.T.; Hummel, S.; Mangler, C.; Pennycook, T.J.; Susi, T.; Meyer, J.C.; Kotakoski, J. |
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Title |
Scanning transmission electron microscopy under controlled low-pressure atmospheres |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
203 |
Issue |
203 |
Pages |
76-81 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Transmission electron microscopy (TEM) is carried out in vacuum to minimize the interaction of the imaging electrons with gas molecules while passing through the microscope column. Nevertheless, in typical devices, the pressure remains at 10(-7) mbar or above, providing a large number of gas molecules for the electron beam to crack, which can lead to structural changes in the sample. Here, we describe experiments carried out in a modified scanning TEM (STEM) instrument, based on the Nion UltraSTEM 100. In this instrument, the base pressure at the sample is around 2 x 10(-10 )mbar, and can be varied up to 10(-6) mbar through introduction of gases directly into the objective area while maintaining atomic resolution imaging conditions. We show that air leaked into the microscope column during the experiment is efficient in cleaning graphene samples from contamination, but ineffective in damaging the pristine lattice. Our experiments also show that exposure to O(2 )and H2O lead to a similar result, oxygen providing an etching effect nearly twice as efficient as water, presumably due to the two 0 atoms per molecule. H(2 )and N-2 environments have no influence on etching. These results show that the residual gas environment in typical TEM instruments can have a large influence on the observations, and show that chemical etching of carbon-based structures can be effectively carried out with oxygen. |
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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 |
000465021000010 |
Publication Date |
2019-02-04 |
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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 |
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 |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843 |
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Call Number |
UA @ admin @ c:irua:165937 |
Serial |
6321 |
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| Permanent link to this record |
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Author |
Fatermans, J.; Van Aert, S.; den Dekker, A.J. |
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Title |
The maximum a posteriori probability rule for atom column detection from HAADF STEM images |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
201 |
Issue |
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Pages |
81-91 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Recently, the maximum a posteriori (MAP) probability rule has been proposed as an objective and quantitative method to detect atom columns and even single atoms from high-resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images. The method combines statistical parameter estimation and model-order selection using a Bayesian framework and has been shown to be especially useful for the analysis of the structure of beam-sensitive nanomaterials. In order to avoid beam damage, images of such materials are usually acquired using a limited incoming electron dose resulting in a low contrast-to-noise ratio (CNR) which makes visual inspection unreliable. This creates a need for an objective and quantitative approach. The present paper describes the methodology of the MAP probability rule, gives its step-by-step derivation and discusses its algorithmic implementation for atom column detection. In addition, simulation results are presented showing that the performance of the MAP probability rule to detect the correct number of atomic columns from HAADF STEM images is superior to that of other model-order selection criteria, including the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC). Moreover, the MAP probability rule is used as a tool to evaluate the relation between STEM image quality measures and atom detectability resulting in the introduction of the so-called integrated CNR (ICNR) as a new image quality measure that better correlates with atom detectability than conventional measures such as signal-to-noise ratio (SNR) and CNR. |
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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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Wos |
000466343800009 |
Publication Date |
2019-02-04 |
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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 |
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 |
1 |
Open Access |
OpenAccess |
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Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (No. W.O.010.16N, No. G.0368.15N, No. G.0502.18N). This project has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (Grant Agreement No. 770887). |
Approved |
Most recent IF: 2.843 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:157176 |
Serial |
5153 |
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Author |
O'Donnell, D.; Hassan, S.; Du, Y.; Gauquelin, N.; Krishnan, D.; Verbeeck, J.; Fan, R.; Steadman, P.; Bencok, P.; Dobrynin, A.N. |
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Title |
Etching induced formation of interfacial FeMn in IrMn/CoFe bilayers |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
52 |
Issue |
16 |
Pages |
165002 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The effect of ion etching on exchange bias in IrMn3/Co70Fe30 bilayers is investigated. In spite of the reduction of saturation magnetization caused by the embedding of Tr from the capping layer into the Co70Fe30 layer during the etching process, the exchange bias in samples with the same thickness of the Co70Fe30 layer is reducing in proportion to the etching power. X-ray magnetic circular dichroism measurements revealed the emergence of an uncompensated Mn magnetization after etching, which is antiferromagnetically coupled to the ferromagnetic layer. This suggests etching induced formation of small interfacial FeMn regions which leads to the decrease of effective exchange coupling between ferromagnetic and antiferromagnetic layers. |
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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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Language |
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Wos |
000458524800001 |
Publication Date |
2019-01-31 |
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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 |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.588 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
; This work was supported by Seagate Technology (Ireland). Beamline I10, Diamond Light Source, is acknowledged for provided beamtime. ; |
Approved |
Most recent IF: 2.588 |
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Call Number |
UA @ admin @ c:irua:157458 |
Serial |
5247 |
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| Permanent link to this record |
