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Records |
Links |
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Author |
Huang, W.; Zhang, X.-B.; Tu, J.; Kong, F.; Ning, Y.; Xu, J.; Van Tendeloo, G. |
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Title |
Synthesis and characterization of graphite nanofibers deposited on nickel foams |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
4 |
Issue |
21 |
Pages |
5325-5329 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nickel foams were used as catalysts to dissociate acetylene and deposit carbon atoms. Graphite nanofibers with distinct structures were developed at 550degreesC with nickel foams pretreated with hydrogen. HREM observations showed that the graphite layers of the nanofibers were aligned at a certain angle to the fiber axis. It is suggested that hydrogen treatment and metal catalysts have a tremendous impact on the yields and microstructures of the graphite nanofibers. The growth mechanism of these fish-bone graphite nanofibers is also discussed. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000178635300016 |
Publication Date |
2002-10-17 |
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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 |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.123; 2002 IF: 1.838 |
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Call Number |
UA @ lucian @ c:irua:94938 |
Serial |
3411 |
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Permanent link to this record |
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Author |
Lobanov, M.V.; Abakumov, A.M.; Sidorova, A.V.; Rozova, M.G.; D'yachenko, O.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G. |
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Title |
Synthesis and investigation of novel Mn-based oxyfluoride Sr2Mn2O5-xF1+x |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Solid state sciences |
Abbreviated Journal |
Solid State Sci |
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Volume |
4 |
Issue |
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Pages |
19-22 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000174141100004 |
Publication Date |
2002-07-25 |
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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 |
1293-2558; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.811 |
Times cited |
21 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.811; 2002 IF: 1.667 |
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Call Number |
UA @ lucian @ c:irua:40346 |
Serial |
3432 |
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Permanent link to this record |
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Author |
Amelinckx, S.; Van Tendeloo, G.; van Landuyt, J. |
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Title |
The study of high Tc-superconducting materials by electron microscopy and electron diffraction |
Type |
A1 Journal article |
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Year |
1991 |
Publication |
Superconductor science and technology
T2 – SATELLITE CONF TO THE 19TH INTERNATIONAL CONF ON LOW TEMPERATURE PHYSICS : HIGH TEMPERATURE SUPERCONDUCTIVITY, AUG 13-15, 1990, QUEENS COLL, CAMBRIDGE, ENGLAND |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
4 |
Issue |
s:[1] |
Pages |
S19-S34 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A survey is given of the application of different electron microscopic techniques to the study of structural features of high T(c)-superconducting materials. Emphasis is laid in this contribution on those structural aspects for the study of which electron microscopy has been essential or has contributed to a significant extent. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
A1991FA42000004 |
Publication Date |
2002-08-25 |
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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 |
0953-2048;1361-6668; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.325 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
PHYSICS, APPLIED 47/145 Q2 # |
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Call Number |
UA @ lucian @ c:irua:104503 |
Serial |
3596 |
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Permanent link to this record |
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Author |
Stuer, C.; van Landuyt, J.; Bender, H.; Rooyackers, R.; Badenes, G. |
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Title |
The use of convergent beam electron diffraction for stress measurements in shallow trench isolation structures |
Type |
A1 Journal article |
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Year |
2001 |
Publication |
Materials science in semiconductor processing |
Abbreviated Journal |
Mat Sci Semicon Proc |
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Volume |
4 |
Issue |
1/3 |
Pages |
117-119 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Shallow trench isolation (STI) is a promising technology for the isolation structures of the new generation of ULSI devices with dimensions below 0.18 mum. The various processing steps cause stress fields in STI structures, which can lead to defect formation in the silicon substrate. In their turn, stress fields affect the electrical parameters and the reliability of devices. Convergent beam electron diffraction (CBED) is used in this study to examine the influence of a wet and a dry pre-gate oxidation on the stress distribution around STI structures. The measurements are performed on STI structures with different width and spacing. CBED analysis is compared with bright-field TEM images. Defects are observed in high-strain areas of small isolated structures. (C) 2001 Elsevier Science Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000167727200028 |
Publication Date |
2002-10-14 |
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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 |
1369-8001; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.359 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.359; 2001 IF: 0.419 |
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Call Number |
UA @ lucian @ c:irua:94968 |
Serial |
3602 |
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Permanent link to this record |
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Author |
Rizzo, F.; Augieri, A.; Angrisani Armenio, A.; Galluzzi, V.; Mancini, A.; Pinto, V.; Rufoloni, A.; Vannozzi, A.; Bianchetti, M.; Kursumovic, A.; MacManus-Driscoll, J.L.; Meledin, A.; Van Tendeloo, G.; Celentano, G. |
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Title |
Enhanced 77K vortex-pinning in YBa2Cu3O7−x films with Ba2YTaO6 and mixed Ba2YTaO6 + Ba2YNbO6 nano-columnar inclusions with irreversibility field to 11T |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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Volume |
4 |
Issue |
4 |
Pages |
061101 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Pulsed laser deposited thin YBa2Cu3O7−x (YBCO) films with pinning additions of 5at.% Ba2YTaO6 (BYTO) were compared to films with 2.5at.% Ba2YTaO6 + 2.5at.% Ba2YNbO6 (BYNTO) additions. Excellent magnetic flux-pinning at 77 K was obtained with remarkably high irreversibility fields greater than 10T (YBCO-BYTO) and 11T (YBCO-BYNTO), representing the highest ever achieved values in YBCO films. |
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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 |
000379042400002 |
Publication Date |
2016-06-08 |
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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 |
2166-532X |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.335 |
Times cited |
19 |
Open Access |
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Notes |
This work was financially supported by EUROTAPES, a collaborative project funded by the European Commission’s Seventh Framework Program (FP7 / 2007-2013) under Grant Agreement no. 280432 |
Approved |
Most recent IF: 4.335 |
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Call Number |
c:irua:133785 |
Serial |
4077 |
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Permanent link to this record |
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Author |
Neubert, S.; Mitoraj, D.; Shevlin, S.A.; Pulisova, P.; Heimann, M.; Du, Y.; Goh, G.K.L.; Pacia, M.; Kruczała, K.; Turner, S.; Macyk, W.; Guo, Z.X.; Hocking, R.K.; Beranek, R.; |
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Title |
Highly efficient rutile TiO2 photocatalysts with single Cu(II) and Fe(III) surface catalytic sites |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
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Volume |
4 |
Issue |
4 |
Pages |
3127-3138 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Highly active photocatalysts were obtained by impregnation of nanocrystalline rutile TiO2 powders with small amounts of Cu(II) and Fe(III) ions, resulting in the enhancement of initial rates of photocatalytic degradation of 4-chlorophenol in water by factors of 7 and 4, compared to pristine rutile, respectively. Detailed structural analysis by EPR and X-ray absorption spectroscopy (EXAFS) revealed that Cu(II) and Fe(III) are present as single species on the rutile surface. The mechanism of the photoactivity enhancement was elucidated by a combination of DFT calculations and detailed experimental mechanistic studies including photoluminescence measurements, photocatalytic experiments using scavengers, OH radical detection, and photopotential transient measurements. The results demonstrate that the single Cu(II) and Fe(III) ions act as effective cocatalytic sites, enhancing the charge separation, catalyzing “dark” redox reactions at the interface, thus improving the normally very low quantum yields of UV light-activated TiO2 photocatalysts. The exact mechanism of the photoactivity enhancement differs depending on the nature of the cocatalyst. Cu(II)-decorated samples exhibit fast transfer of photogenerated electrons to Cu(II/I) sites, followed by enhanced catalysis of dioxygen reduction, resulting in improved charge separation and higher photocatalytic degradation rates. At Fe(III)-modified rutile the rate of dioxygen reduction is not improved and the photocatalytic enhancement is attributed to higher production of highly oxidizing hydroxyl radicals produced by alternative oxygen reduction pathways opened by the presence of catalytic Fe(III/II) sites. Importantly, it was demonstrated that excessive heat treatment (at 450 degrees C) of photocatalysts leads to loss of activity due to migration of Cu(II) and Fe(III) ions from TiO2 surface to the bulk, accompanied by formation of oxygen vacancies. The demonstrated variety of mechanisms of photoactivity enhancement at single site catalyst-modified photocatalysts holds promise for developing further tailored photocatalysts for various applications. |
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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 |
Cambridge |
Editor |
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Language |
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Wos |
000371077300040 |
Publication Date |
2015-12-30 |
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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 |
2050-7488; 2050-7496 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.867 |
Times cited |
44 |
Open Access |
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Notes |
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Approved |
Most recent IF: 8.867 |
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Call Number |
UA @ lucian @ c:irua:132322 |
Serial |
4191 |
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Permanent link to this record |
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Author |
Naik, P.V.; Wee, L.H.; Meledina, M.; Turner, S.; Li, Y.; Van Tendeloo, G.; Martens, J.A.; Vankelecom, I.F.J. |
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Title |
PDMS membranes containing ZIF-coated mesoporous silica spheres for efficient ethanol recovery via pervaporation |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
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Volume |
4 |
Issue |
4 |
Pages |
12790-12798 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The design of functional micro- and mesostructured composite materials is significantly important for separation processes. Mesoporous silica is an attractive material for fast diffusion, while microporous zeolitic imidazolate frameworks (ZIFs) are beneficial for selective adsorption and diffusion. In this work, ZIF-71 and ZIF-8 nanocrystals were grown on the surface of mesoporous silica spheres (MSS) via the seeding and regrowth approach in order to obtain monodispersed MSS-ZIF-71 and MSS-ZIF-8 spheres with a particle size of 2-3 mm. These MSS-ZIF spheres were uniformly dispersed into a polydimethylsiloxane (PDMS) matrix to prepare mixed matrix membranes (MMMs). These MMMs were evaluated for the separation of ethanol from water via pervaporation. The pervaporation results reveal that the MSS-ZIF filled MMMs substantially improve the ethanol recovery in both aspects viz. flux and separation factor. These MMMs outperforms the unfilled PDMS membranes and the conventional carbon and zeolite filled MMMs. As expected, the mesoporous silica core allows very fast flow of the permeating compound, while the hydrophobic ZIF coating enhances the ethanol selectivity through its specific pore structure, hydrophobicity and surface chemistry. It can be seen that ZIF-8 mainly has a positive impact on the selectivity, while ZIF-71 enhances fluxes more significantly. |
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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 |
Cambridge |
Editor |
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Language |
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Wos |
000382015100012 |
Publication Date |
2016-07-12 |
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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 |
2050-7488; 2050-7496 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.867 |
Times cited |
26 |
Open Access |
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Notes |
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Approved |
Most recent IF: 8.867 |
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Call Number |
UA @ lucian @ c:irua:137188 |
Serial |
4395 |
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Permanent link to this record |
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Author |
Van Havenbergh, K.; Turner, S.; Marx, N.; Van Tendeloo, G. |
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Title |
The mechanical behavior during (de)lithiation of coated silicon nanoparticles as anode material for lithium-ion batteries studied by InSitu transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Energy technology |
Abbreviated Journal |
Energy Technol-Ger |
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Volume |
4 |
Issue |
4 |
Pages |
1005-1012 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
One approach to cope with the continuous irreversible capacity loss in Si-based electrodes, attributed to lithiation-induced volume changes and the formation of a solid-electrolyte interface (SEI), is by coating silicon nanoparticles. A coating can improve the conductivity of the electrode, form a chemical shield against the electrolyte, or provide mechanical confinement to reduce the volume increase. The influence of such a coating on the mechanical behavior of silicon nanoparticles during Li insertion and Li extraction was investigated by insitu transmission electron microscopy. The type of coating was shown to influence the size of the unreacted core that remains after reaction of silicon with lithium. Furthermore, two mechanisms to relieve the stress generated during volume expansion are reported: the initiation of cracks and the formation of nanovoids. Both result in a full reaction of the silicon nanoparticles, whereas with the formation of cracks, additional surface area is created, on which an SEI can be formed. |
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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 |
000382549500012 |
Publication Date |
2016-06-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2194-4296; 2194-4288 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.789 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:137167 |
Serial |
4406 |
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Permanent link to this record |
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Author |
Ata, I.; Ben Dkhil, S.; Pfannmoeller, M.; Bals, S.; Duche, D.; Simon, J.-J.; Koganezawa, T.; Yoshimoto, N.; Videlot-Ackermann, C.; Margeat, O.; Ackermann, J.; Baeuerle, P. |
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Title |
The influence of branched alkyl side chains in A-D-A oligothiophenes on the photovoltaic performance and morphology of solution-processed bulk-heterojunction solar cells |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Organic chemistry frontiers : an international journal of organic chemistry |
Abbreviated Journal |
Org Chem Front |
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Volume |
4 |
Issue |
4 |
Pages |
1561-1573 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Besides providing sufficient solubility, branched alkyl chains also affect the film-forming and packing properties of organic semiconductors. In order to avoid steric hindrance as it is present in wide-spread alkyl chains comprising a branching point position at the C2-position, i.e., 2-ethylhexyl, the branching point can be moved away from the pi-conjugated backbone. In this report, we study the influence of the modification of the branching point position from the C2-position in 2-hexyldecylamine (1) to the C4-position in 4-hexyldecylamine (2) connected to the central dithieno[3,2-b: 2', 3'-d] pyrrole (DTP) moiety in a well-studied A-D-A oligothiophene on the optoelectronic properties and photovoltaic performance in solution- processed bulk heterojunction solar cells (BHJSCs) with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor material. Post-treatment of the photoactive layers is performed via solvent vapor annealing (SVA) in order to improve the film microstructure of the bulk heterojunction. The time evolution of nanoscale morphological changes is followed by combining scanning transmission electron microscopy with low-energy-loss spectroscopic imaging (STEM-SI), solid-state absorption spectroscopy, and two-dimensional grazing incidence X-ray diffraction (2D-GIXRD). Our results show an improvement of the photovoltaic performance that is dependent on the branching point position in the donor oligomer. Optical spacers are utilized to increase light absorption inside the co-oligomer 2-based BHJSCs leading to increased power conversion efficiencies (PCEs) of 8.2% when compared to the corresponding co-oligomer 1-based devices. A STEM-SI analysis of the respective device cross-sections of active layers containing 1 and 2 as donor materials indeed reveals significant differences in their respective active layer morphologies. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
RSC Publishing |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000406374800013 |
Publication Date |
2017-05-02 |
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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 |
2052-4129 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.955 |
Times cited |
24 |
Open Access |
OpenAccess |
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Notes |
; We acknowledge financial support by the European Commission under the project “SUNFLOWER” (FP7-ICT-2011-7, grant number: 287594) and S.B. acknowledges the ERC Starting Grant Colouratoms (335078). ; |
Approved |
Most recent IF: 4.955 |
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Call Number |
UA @ lucian @ c:irua:145176UA @ admin @ c:irua:145176 |
Serial |
4727 |
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Permanent link to this record |
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Author |
Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Altantzis, T.; Sada, C.; Kaunisto, K.; Ruoko, T.-P.; Bals, S. |
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Title |
Vapor Phase Fabrication of Nanoheterostructures Based on ZnO for Photoelectrochemical Water Splitting |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
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Volume |
4 |
Issue |
4 |
Pages |
1700161 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nanoheterostructures based on metal oxide semiconductors have emerged
as promising materials for the conversion of sunlight into chemical energy.
In the present study, ZnO-based nanocomposites have been developed by
a hybrid vapor phase route, consisting in the chemical vapor deposition
of ZnO systems on fluorine-doped tin oxide substrates, followed by the
functionalization with Fe2O3 or WO3 via radio frequency-sputtering. The
target systems are subjected to thermal treatment in air both prior and after
sputtering, and their properties, including structure, chemical composition,
morphology, and optical absorption, are investigated by a variety of characterization
methods. The obtained results evidence the formation of highly
porous ZnO nanocrystal arrays, conformally covered by an ultrathin Fe2O3
or WO3 overlayer. Photocurrent density measurements for solar-triggered
water splitting reveal in both cases a performance improvement with respect
to bare zinc oxide, that is mainly traced back to an enhanced separation of
photogenerated charge carriers thanks to the intimate contact between the
two oxides. This achievement can be regarded as a valuable result in view of
future optimization of similar nanoheterostructured photoanodes. |
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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 |
000411525700007 |
Publication Date |
2017-05-15 |
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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 |
2196-7350 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.279 |
Times cited |
30 |
Open Access |
OpenAccess |
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Notes |
The authors kindly acknowledge the financial support under Padova University ex-60% 2013–2016, P-DiSC #SENSATIONAL BIRD2016- UNIPD projects and the post-doc fellowship ACTION. S.B. acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078) and T.A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. Many thanks are also due to Dr. Rosa Calabrese (Department of Chemistry, Padova University, Italy) for experimental assistance. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; |
Approved |
Most recent IF: 4.279 |
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Call Number |
EMAT @ emat @c:irua:146104UA @ admin @ c:irua:146104 |
Serial |
4731 |
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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 |
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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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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 |
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 |
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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 |
Daems, N.; De Mot, B.; Choukroun, D.; Van Daele, K.; Li, C.; Hubin, A.; Bals, S.; Hereijgers, J.; Breugelmans, T. |
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Title |
Nickel-containing N-doped carbon as effective electrocatalysts for the reduction of CO2 to CO in a continuous-flow electrolyzer |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Sustainable energy & fuels |
Abbreviated Journal |
|
|
|
Volume |
4 |
Issue |
4 |
Pages |
1296-1311 |
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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 |
Nickel-containing N-doped carbons were synthesized for the electrochemical reduction of CO2 to CO, which is a promising approach to reduce the atmospheric CO2 levels and its negative impact on the environment. Unfortunately, poor performance (activity, selectivity and/or stability) is still a major hurdle for the economical implementation of this type of materials. The electrocatalysts were prepared through an easily up-scalable and easily tunable method based on the pyrolysis of Ni-containing N-doped carbons. Ni–N–AC–B1 synthesized with a high relative amount of nitrogen and nickel with respect to carbon, was identified as the most promising candidate for this reaction based on its partial CO current density (4.2 mA cm−2), its overpotential (0.57 V) and its faradaic efficiency to CO (>99%). This results in unprecedented values for the current density per g active sites (690 A g−1 active sites). Combined with its decent stability and its high performance in an actual electrolyzer setup, this makes it a promising candidate for the electrochemical reduction of CO2 to CO on a larger scale. Finally, the evaluation of this kind of material in a flow-cell setup has been limited and to the best of our knowledge never included an evaluation of several crucial parameters (e.g. electrolyte type, anode composition and membrane type) and is an essential investigation in the move towards up-scaling and ultimately industrial application of this technique. This study resulted in an optimal cell configuration, consisting of Pt as an anode, Fumatech® as the membrane and 1 M KHCO3 and 2 M KOH as catholyte and anolyte, respectively. In conclusion, this research offers a unique combination of electrocatalyst development and reactor optimization. |
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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 |
000518690900030 |
Publication Date |
2019-12-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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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 |
14 |
Open Access |
OpenAccess |
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Notes |
; The authors acknowledge sponsoring from the research foundation of Flanders (FWO) in the frame of a post-doctoral grant (12Y3919N – ND). J. Hereijgers was supported through a postdoctoral fellowship (28761) of the Research Foundation Flanders (FWO). This project was co-funded by the Interreg 2 Seas-Program 2014-2020, co-.nanced by the European Fund for Regional Development in the frame of subsidiary contract nr 2S03-019. This work was further performed in the framework of the Catalisti cluster SBO project CO2PERATE (“All renewable CCU based on formic acid integrated in an industrial microgrid”), with the.nancial support of VLAIO (Flemish Agency for Innovation and Entrepreneurship). This project.nally received funding from the European Research Council (ERC Consolidator Grant 815128, REALNANO). We thank Karen Leyssens for helping with the N<INF>2</INF> physisorption measurements and Kitty Baert (VUB) for analyzing the samples with XPS and Raman. ; sygma |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:165482 |
Serial |
6311 |
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Permanent link to this record |
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Author |
Chen, B.; Gauquelin, N.; Reith, P.; Halisdemir, U.; Jannis, D.; Spreitzer, M.; Huijben, M.; Abel, S.; Fompeyrine, J.; Verbeeck, J.; Hilgenkamp, H.; Rijnders, G.; Koster, G. |
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Title |
Thermal-strain-engineered ferromagnetism of LaMnO3/SrTiO3 heterostructures grown on silicon |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical review materials |
Abbreviated Journal |
Phys. Rev. Materials |
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Volume |
4 |
Issue |
2 |
Pages |
024406 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The integration of oxides on Si remains challenging, which largely hampers the practical applications of oxide-based electronic devices with superior performance. Recently, LaMnO3/SrTiO3 (LMO/STO) heterostructures have gained renewed interest for the debating origin of the ferromagnetic-insulating ground state as well as for their spin-filter applications. Here we report on the structural and magnetic properties of high-quality LMO/STO heterostructures grown on silicon. The chemical abruptness across the interface was investigated by atomic-resolution scanning transmission electron microscopy. The difference in the thermal expansion coefficients between LMO and Si imposed a large biaxial tensile strain to the LMO film, resulting in a tetragonal structure with c/a∼ 0.983. Consequently, we observed a significantly suppressed ferromagnetism along with an enhanced coercive field, as compared to the less distorted LMO film (c/a∼1.004) grown on STO single crystal. The results are discussed in terms of tensile-strain enhanced antiferromagnetic instabilities. Moreover, the ferromagnetism of LMO on Si sharply disappeared below a thickness of 5 unit cells, in agreement with the LMO/STO case, pointing to a robust critical behavior irrespective of the strain state. Our results demonstrate that the growth of oxide films on Si can be a promising way to study the tensile-strain effects in correlated oxides, and also pave the way towards the integration of multifunctional oxides on Si with atomic-layer control. |
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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 |
000513552900003 |
Publication Date |
2020-02-12 |
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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 |
3.4 |
Times cited |
6 |
Open Access |
Not_Open_Access |
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Notes |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Vlaamse regering; Fonds Wetenschappelijk Onderzoek, G093417N ; Javna Agencija za Raziskovalno Dejavnost RS, J2-9237 P2-0091 ; European Commission, H2020-ICT-2016-1-732642 ; |
Approved |
Most recent IF: 3.4; 2020 IF: NA |
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Call Number |
EMAT @ emat @c:irua:167782 |
Serial |
6375 |
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Permanent link to this record |
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Author |
Araizi-Kanoutas, G.; Geessinck, J.; Gauquelin, N.; Smit, S.; Verbeek, X.H.; Mishra, S.K.; Bencok, P.; Schlueter, C.; Lee, T.-L.; Krishnan, D.; Fatermans, J.; Verbeeck, J.; Rijnders, G.; Koster, G.; Golden, M.S. |
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Title |
Co valence transformation in isopolar LaCoO3/LaTiO3 perovskite heterostructures via interfacial engineering |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical review materials |
Abbreviated Journal |
Phys. Rev. Materials |
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Volume |
4 |
Issue |
2 |
Pages |
026001 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report charge transfer up to a single electron per interfacial unit cell across nonpolar heterointerfaces from the Mott insulator LaTiO3 to the charge transfer insulator LaCoO3. In high-quality bi- and trilayer systems grown using pulsed laser deposition, soft x-ray absorption, dichroism, and scanning transmission electron microscopy-electron energy loss spectroscopy are used to probe the cobalt-3d electron count and provide an element-specific investigation of the magnetic properties. The experiments show the cobalt valence conversion is active within 3 unit cells of the heterointerface, and able to generate full conversion to 3d7 divalent Co, which displays a paramagnetic ground state. The number of LaTiO3/LaCoO3 interfaces, the thickness of an additional, electronically insulating “break” layer between the LaTiO3 and LaCoO3, and the LaCoO3 film thickness itself in trilayers provide a trio of control knobs for average charge of the cobalt ions in LaCoO3, illustrating the efficacy of O−2p band alignment as a guiding principle for property design in complex oxide heterointerfaces. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000513551200007 |
Publication Date |
2020-02-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
13 |
Open Access |
OpenAccess |
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Notes |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Horizon 2020, 730872 ; Department of Science and Technology, Ministry of Science and Technology, SR/NM/Z-07/2015 ; Jawaharlal Nehru Centre for Advanced Scientific Research; |
Approved |
Most recent IF: 3.4; 2020 IF: NA |
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Call Number |
EMAT @ emat @c:irua:167787 |
Serial |
6376 |
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Permanent link to this record |
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Author |
Lin, S.-C.; Kuo, C.-T.; Shao, Y.-C.; Chuang, Y.-D.; Geessinck, J.; Huijben, M.; Rueff, J.-P.; Graff, I.L.; Conti, G.; Peng, Y.; Bostwick, A.; Gullikson, E.; Nemsak, S.; Vailionis, A.; Gauquelin, N.; Verbeeck, J.; Ghiringhelli, G.; Schneider, C.M.; Fadley, C.S. |
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Title |
Two-dimensional electron systems in perovskite oxide heterostructures : role of the polarity-induced substitutional defects |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
4 |
Issue |
11 |
Pages |
115002 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The discovery of a two-dimensional electron system (2DES) at the interfaces of perovskite oxides such as LaAlO3 and SrTiO3 has motivated enormous efforts in engineering interfacial functionalities with this type of oxide heterostructures. However, the fundamental origins of the 2DES are still not understood, e.g., the microscopic mechanisms of coexisting interface conductivity and magnetism. Here we report a comprehensive spectroscopic investigation on the depth profile of 2DES-relevant Ti 3d interface carriers using depthand element-specific techniques like standing-wave excited photoemission and resonant inelastic scattering. We found that one type of Ti 3d interface carriers, which give rise to the 2DES are located within three unit cells from the n-type interface in the SrTiO3 layer. Unexpectedly, another type of interface carriers, which are polarity-induced Ti-on-Al antisite defects, reside in the first three unit cells of the opposing LaAlO3 layer (similar to 10 angstrom). Our findings provide a microscopic picture of how the localized and mobile Ti 3d interface carriers distribute across the interface and suggest that the 2DES and 2D magnetism at the LaAlO3/SrTiO3 interface have disparate explanations as originating from different types of interface carriers. |
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Language |
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Wos |
000592432200004 |
Publication Date |
2020-11-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
7 |
Open Access |
OpenAccess |
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Notes |
; We thank G. M. De Luca and L. Braicovich for discussions. Charles S. Fadley was deceased on August 1, 2019. We are grateful for his significant contributions to this work. We thank Advanced Light Source for the access to Beamline 8.0.3 (qRIXS) via Proposal No. 09892 and beamline 7.0.2 (MAESTRO) via Proposal No. RA-00291 that contributed to the results presented here. We thank synchrotron SOLEIL (via Proposal No. 99180118) for the access to Beamline GALAXIES. This work was supported by the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231 (Advanced Light Source), and by DOE Contract No. DE-SC0014697 through the University of California, Davis (S.-C.L., C.-T.K, and C.S.F.), and from the Julich Research Center, Peter Grunberg Institute, PGI-6. I. L. G. wishes to thank Brazilian scientific agencies CNPQ (Project No. 200789/2017-1) and CAPES (CAPES-PrInt-UFPR) for their financial support. J.V. and N.G. acknowledge funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and the European Union's horizon 2020 research and innovation program ES-TEEM3 under grant agreement no 823717. The Qu-Ant-EM microscope used in this study was partly funded by the Hercules fund from the Flemish Government. ; esteem3TA; esteem3reported |
Approved |
Most recent IF: 3.4; 2020 IF: NA |
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Call Number |
UA @ admin @ c:irua:174316 |
Serial |
6713 |
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Permanent link to this record |
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Author |
Herzog, M.J.; Gauquelin, N.; Esken, D.; Verbeeck, J.; Janek, J. |
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Title |
Increased Performance Improvement of Lithium-Ion Batteries by Dry Powder Coating of High-Nickel NMC with Nanostructured Fumed Ternary Lithium Metal Oxides |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
ACS Appl. Energy Mater. |
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Volume |
4 |
Issue |
9 |
Pages |
8832-8848 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Dry powder coating is an effective approach to protect the surfaces of layered cathode active materials (CAMs) in lithium-ion batteries. Previous investigations indicate an incorporation of lithium ions in fumed Al2O3, ZrO2, and TiO2 coatings on LiNi0.7Mn0.15Co0.15O2 during cycling, improving the cycling performance. Here, this coating approach is transferred for the first time to fumed ternary LiAlO2, Li4Zr3O8, and Li4Ti5O12 and directly compared with their lithium-free equivalents. All materials could be processed equally and their nanostructured small aggregates accumulate on the CAM surfaces to quite homogeneous coating layers with a certain porosity. The LiNixMnyCozO2 (NMC) coated with lithium-containing materials shows an enhanced improvement in overall capacity, capacity retention, rate performance, and polarization behavior during cycling, compared to their lithium-free analogues. The highest rate performance was achieved with the fumed ZrO2 coating, while the best long-term cycling stability with the highest absolute capacity was obtained for the fumed LiAlO2-coated NMC. The optimal coating agent for NMC to achieve a balanced system is fumed Li4Ti5O12, providing a good compromise between high rate capability and good capacity retention. The coating agents prevent CAM particle cracking and degradation in the order LiAlO2 ≈ Al2O3 > Li4Ti5O12 > Li4Zr3O8 > ZrO2 > TiO2. A schematic model for the protection and electrochemical performance enhancement of high-nickel NMC with fumed metal oxide coatings is sketched. It becomes apparent that physical and chemical characteristics of the coating significantly influence the performance of NMC. A high degree of coating-layer porosity is favorable for the rate capability, while a high coverage of the surface, especially in vulnerable grain boundaries, enhances the long-term cycling stability and improves the cracking behavior of NMCs. While zirconium-containing coatings possess the best chemical properties for high rate performances, aluminum-containing coatings feature a superior chemical nature to protect high-nickel NMCs. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000703338600018 |
Publication Date |
2021-09-27 |
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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 |
2574-0962 |
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 |
15 |
Open Access |
OpenAccess |
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Notes |
For his support in scanning electron microscopy analysis, the authors thank Erik Peldszus. N. G. and J. V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and from the Flemish Research Fund (FWO) project G0F1320N. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @c:irua:183949 |
Serial |
6823 |
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Permanent link to this record |
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Author |
Abakumov, A.M.; Li, C.; Boev, A.; Aksyonov, D.A.; Savina, A.A.; Abakumova, T.A.; Van Tendeloo, G.; Bals, S. |
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Title |
Grain boundaries as a diffusion-limiting factor in lithium-rich NMC cathodes for high-energy lithium-ion batteries |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
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Volume |
4 |
Issue |
7 |
Pages |
6777-6786 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
High-energy lithium-rich layered transition metal oxides are capable of delivering record electrochemical capacity and energy density as positive electrodes for Li-ion batteries. Their electrochemical behavior is extremely complex due to sophisticated interplay between crystal structure, electronic structure, and defect structure. Here we unravel an extra level of this complexity by revealing that the most typical representative Li1.2Ni0.13Mn0.54Co0.13O2 material, prepared by a conventional coprecipitation technique with Na2CO3 as a precipitating agent, contains abundant coherent (001) grain boundaries with a Na-enriched P2-structured block due to segregation of the residual sodium traces. The trigonal prismatic oxygen coordination of Na triggers multiple nanoscale twinning, giving rise to incoherent (104) boundaries. The cationic layers at the (001) grain boundaries are filled with transition metal cations being Mn-depleted and Co-enriched; this makes them virtually not permeable for the Li+ cations, and therefore they negatively influence the Li diffusion in and out of the spherical agglomerates. These results demonstrate that besides the mechanisms intrinsic to the crystal and electronic structure of Li-rich cathodes, their rate capability might also be depreciated by peculiar microstructural aspects. Dedicated engineering of grain boundaries opens a way for improving inherently sluggish kinetics of these materials. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000678382900042 |
Publication Date |
2021-07-02 |
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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 |
2574-0962 |
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 |
4 |
Open Access |
OpenAccess |
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Notes |
We thank Dr. M. V. Berekchiian (MSU) for assisting in ICPMS measurements. We acknowledge Russian Science Foundation (Grant 20-43-01012) and Research Foundation Flanders (FWO Vlaanderen, Project No. G0F1320N) for financial support. |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:180556 |
Serial |
6841 |
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Permanent link to this record |
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Author |
Heyvaert, W.; Pedrazo-Tardajos, A.; Kadu, A.; Claes, N.; González-Rubio, G.; Liz-Marzán, L.M.; Albrecht, W.; Bals, S. |
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Title |
Quantification of the Helical Morphology of Chiral Gold Nanorods |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
ACS materials letters |
Abbreviated Journal |
ACS Materials Lett. |
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Volume |
4 |
Issue |
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Pages |
642-649 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Chirality in inorganic nanoparticles and nanostructures has gained increasing scientific interest, because of the possibility to tune their ability to interact differently with left- and right-handed circularly polarized light. In some cases, the optical activity is hypothesized to originate from a chiral morphology of the nanomaterial. However, quantifying the degree of chirality in objects with sizes of tens of nanometers is far from straightforward. Electron tomography offers the possibility to faithfully retrieve the three-dimensional morphology of nanomaterials, but only a qualitative interpretation of the morphology of chiral nanoparticles has been possible so far. We introduce herein a methodology that enables us to quantify the helicity of complex chiral nanomaterials, based on the geometrical properties of a helix. We demonstrate that an analysis at the single particle level can provide significant insights into the origin of chiroptical properties. |
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Place of Publication |
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Language |
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Wos |
000784490000013 |
Publication Date |
2022-03-08 |
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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 |
2639-4979 |
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 |
S.B. and A.P.-T. gratefully acknowledge funding by the European Research Council (ERC Consolidator Grant #815128-REALNANO) the European Union’s Horizon 2020 research and innovation program under grant agreement #823717ESTEEM3. L.M.L.-M. acknowledges funding from MCIN/ AEI /10.13039/501100011033, grant # PID2020- 117779RB-I00 and the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720). G.G.-R. thanks the Spanish Spanish Ministerio de Ciencia e Innovación for an FPI (BES-2014- 068972) fellowship.; SygmaSB; esteem3reported; esteem3jra |
Approved |
Most recent IF: NA |
|
|
Call Number |
EMAT @ emat @c:irua:186959 |
Serial |
6956 |
|
Permanent link to this record |
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Author |
Poulain, R.; Lumbeeck, G.; Hunka, J.; Proost, J.; Savolainen, H.; Idrissi, H.; Schryvers, D.; Gauquelin, N.; Klein, A. |
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|
Title |
Electronic and chemical properties of nickel oxide thin films and the intrinsic defects compensation mechanism |
Type |
A1 Journal article |
|
Year |
2022 |
Publication |
ACS applied electronic materials |
Abbreviated Journal |
|
|
|
Volume |
4 |
Issue |
6 |
Pages |
2718-2728 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Although largely studied, contradictory results on nickel oxide (NiO) properties can be found in the literature. We herein propose a comprehensive study that aims at leveling contradictions related to NiO materials with a focus on its conductivity, surface properties, and the intrinsic charge defects compensation mechanism with regards to the conditions preparation. The experiments were performed by in situ photo-electron spectroscopy, electron energy loss spectroscopy, and optical as well as electrical measurements on polycrystalline NiO thin films prepared under various preparation conditions by reactive sputtering. The results show that surface and bulk properties were strongly related to the deposition temperature with in particular the observation of Fermi level pinning, high work function, and unstable oxygen-rich grain boundaries for the thin films produced at room temperature but not at high temperature (>200 degrees C). Finally, this study provides substantial information about surface and bulk NiO properties enabling to unveil the origin of the high electrical conductivity of room temperature NiO thin films and also for supporting a general electronic charge compensation mechanism of intrinsic defects according to the deposition temperature. |
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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 |
000819431200001 |
Publication Date |
2022-06-07 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2637-6113 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
|
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:189555 |
Serial |
7081 |
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Permanent link to this record |
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Author |
Birkholzer, Y.A.; Sotthewes, K.; Gauquelin, N.; Riekehr, L.; Jannis, D.; van der Minne, E.; Bu, Y.; Verbeeck, J.; Zandvliet, H.J.W.; Koster, G.; Rijnders, G. |
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Title |
High-strain-induced local modification of the electronic properties of VO₂ thin films |
Type |
A1 Journal article |
|
Year |
2022 |
Publication |
ACS applied electronic materials |
Abbreviated Journal |
|
|
|
Volume |
4 |
Issue |
12 |
Pages |
6020-6028 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Vanadium dioxide (VO2) is a popular candidate for electronic and optical switching applications due to its well-known semiconductor-metal transition. Its study is notoriously challenging due to the interplay of long- and short-range elastic distortions, as well as the symmetry change and the electronic structure changes. The inherent coupling of lattice and electronic degrees of freedom opens the avenue toward mechanical actuation of single domains. In this work, we show that we can manipulate and monitor the reversible semiconductor-to-metal transition of VO2 while applying a controlled amount of mechanical pressure by a nanosized metallic probe using an atomic force microscope. At a critical pressure, we can reversibly actuate the phase transition with a large modulation of the conductivity. Direct tunneling through the VO2-metal contact is observed as the main charge carrier injection mechanism before and after the phase transition of VO2. The tunneling barrier is formed by a very thin but persistently insulating surface layer of the VO2. The necessary pressure to induce the transition decreases with temperature. In addition, we measured the phase coexistence line in a hitherto unexplored regime. Our study provides valuable information on pressure-induced electronic modifications of the VO2 properties, as well as on nanoscale metal-oxide contacts, which can help in the future design of oxide electronics. |
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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 |
000890974900001 |
Publication Date |
2022-11-18 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2637-6113 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
|
Times cited |
2 |
Open Access |
OpenAccess |
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|
Notes |
This work received financial support from the project Green ICT (grant number 400.17.607) of the research program NWA, which is financed by the Dutch Research Council (NWO), Research Foundation Flanders (FWO grant number G0F1320N), and the European Union’s Horizon 2020 research and innovation program within a contract for Integrating Activities for Advanced Communities (grant number 823717 − ESTEEM3). The K2 camera was funded through the Research Foundation Flanders (FWO-Hercules grant number G0H4316N – “Direct electron detector for soft matter TEM”).; esteem3reported; esteem3jra |
Approved |
Most recent IF: NA |
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|
Call Number |
UA @ admin @ c:irua:192712 |
Serial |
7309 |
|
Permanent link to this record |
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Author |
Yu, R.; Zeng, W.; Zhou, L.; Van Tendeloo, G.; Mai, L.; Yao, Z.; Wu, J. |
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Title |
Layer-by-layer delithiation during lattice collapse as the origin of planar gliding and microcracking in Ni-rich cathodes |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Cell reports physical science |
Abbreviated Journal |
|
|
|
Volume |
4 |
Issue |
7 |
Pages |
101480-14 |
|
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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|
Abstract |
High-energy-density nickel (Ni)-rich cathode materials are used in commercial lithium (Li)-ion batteries for electric vehicles, but they suffer from severe structural degradation upon cycling. Planar gliding and microcracking are seeds for fatal mechanical fracture, but their origin remains unclear. Herein, we show that “layer-by -layer delithiation”is activated at high voltages during the charge process when the “lattice collapse”(a characteristic high-voltage lattice evolution in Ni-rich cathodes) occurs. Layer-by-layer deli-thiation is evidenced by direct observation of the consecutive lattice collapse using in situ scanning transmission electron micro-scopy (STEM). The collapsing of the lattice initiates in the expanded planes and consecutively extends to the whole crystal. Localized strain will be induced at lattice-collapsing interface where planar gliding and intragranular microcracks are generated to release this strain. Our study reveals that layer-by-layer delithia-tion during lattice collapse is the fundamental origin of the mechanical instability in single-crystalline Ni-rich cathodes. |
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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 |
001048074500001 |
Publication Date |
2023-06-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
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|
Notes |
|
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:198299 |
Serial |
8893 |
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Permanent link to this record |
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Author |
Bals, S.; Van Aert, S.; Romero, C.P.; Lauwaet, K.; Van Bael, M.J.; Schoeters, B.; Partoens, B.; Yuecelen, E.; Lievens, P.; Van Tendeloo, G. |
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Title |
Atomic scale dynamics of ultrasmall germanium clusters |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
|
|
Volume |
3 |
Issue |
897 |
Pages |
897 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
|
Abstract |
Starting from the gas phase, small clusters can be produced and deposited with huge flexibility with regard to composition, materials choice and cluster size. Despite many advances in experimental characterization, a detailed morphology of such clusters is still lacking. Here we present an atomic scale observation as well as the dynamical behaviour of ultrasmall germanium clusters. Using quantitative scanning transmission electron microscopy in combination with ab initio calculations, we are able to characterize the transition between different equilibrium geometries of a germanium cluster consisting of less than 25 atoms. Seven-membered rings, trigonal prisms and some smaller subunits are identified as possible building blocks that stabilize the structure. |
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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 |
000306099900024 |
Publication Date |
2012-06-12 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2041-1723; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
12.124 |
Times cited |
90 |
Open Access |
|
|
|
Notes |
Fwo; Iap; Iwt |
Approved |
Most recent IF: 12.124; 2012 IF: 10.015 |
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Call Number |
UA @ lucian @ c:irua:100340 |
Serial |
183 |
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Permanent link to this record |
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Author |
Godefroo, S.; Hayne, M.; Jivanescu, M.; Stesmans, A.; Zacharias, M.; Lebedev, O.I.; Van Tendeloo, G.; Moshchalkov, V.V. |
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Title |
Classification and control of the origin of photoluminescence from Si nanocrystals |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
|
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Volume |
3 |
Issue |
3 |
Pages |
174-178 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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|
Abstract |
Silicon dominates the electronics industry, but its poor optical properties mean that III-V compound semiconductors are preferred for photonics applications. Photoluminescence at visible wavelengths was observed from porous Si at room temperature in 1990, but the origin of these photons (do they arise from highly localized defect states or quantum confinement effects?) has been the subject of intense debate ever since. Attention has subsequently shifted from porous Si to Si nanocrystals, but the same fundamental question about the origin of the photoluminescence has remained. Here we show, based on measurements in high magnetic fields, that defects are the dominant source of light from Si nanocrystals. Moreover, we show that it is possible to control the origin of the photoluminescence in a single sample: passivation with hydrogen removes the defects, resulting in photoluminescence from quantum-confined states, but subsequent ultraviolet illumination reintroduces the defects, making them the origin of the light again. |
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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 |
000254743600017 |
Publication Date |
2008-03-02 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1748-3387;1748-3395; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
38.986 |
Times cited |
426 |
Open Access |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 38.986; 2008 IF: 20.571 |
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|
Call Number |
UA @ lucian @ c:irua:102630 |
Serial |
373 |
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Permanent link to this record |
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Author |
Mei, B.; Wiktor, C.; Turner, S.; Pougin, A.; Van Tendeloo, G.; Fischer, R.A.; Muhler, M.; Strunk, J. |
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Title |
Evidence for metalsupport interactions in Au modified TiOx/SBA-15 materials prepared by photodeposition |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
3 |
Issue |
12 |
Pages |
3041-3049 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Gold nanoparticles have been efficiently photodeposited onto titanate-loaded SBA-15 (Ti(x)/SBA-15) with different titania coordination. Transmission electron microscopy shows that relatively large Au nanoparticles are photodeposited on the outer surface of the Ti(x)/SBA-15 materials and that TiOx tends to form agglomerates in close proximity to the Au nanoparticles, often forming coreshell Au/TiOx structures. This behavior resembles typical processes observed due to strong-metal support interactions. In the presence of gold, the formation of hydrogen on Ti(x)/SBA-15 during the photodeposition process and the performance in the hydroxylation of terephthalic acid is greatly enhanced. The activity of the Au/Ti(x)/SBA-15 materials is found to depend on the TiOx loading, increasing with a larger amount of initially isolated TiO4 tetrahedra. Samples with initially clustered TiOx species show lower photocatalytic activities. When isolated zinc oxide (ZnOx) species are present on Ti(x)/SBA-15, gold nanoparticles are smaller and well dispersed within the pores. Agglomeration of TiOx species and the formation of Au/TiOx structures is negligible. The dispersion of gold and the formation of Au/TiOx in the SBA-15 matrix seem to depend on the mobility of the TiOx species. The mobility is determined by the initial degree of agglomeration of TiOx. Effective hydrogen evolution requires Au/TiOx coreshell composites as in Au/Ti(x)/SBA-15, whereas hydroxylation of terephthalic acid can also be performed with Au/ZnOx/TiOx/SBA-15 materials. However, isolated TiOx species have to be grafted onto the support prior to the zinc oxide species, providing strong evidence for the necessity of TiOSi bridges for high photocatalytic activity in terephthalic acid hydroxylation. |
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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 |
000328231400044 |
Publication Date |
2013-11-05 |
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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 |
|
Series Issue |
|
Edition |
|
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ISSN |
2155-5435;2155-5435; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
22 |
Open Access |
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Notes |
262348 ESMI; FWO; 246791 COUNTATOMS; IAP-PAI; Hercules |
Approved |
Most recent IF: 10.614; 2013 IF: 7.572 |
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Call Number |
UA @ lucian @ c:irua:112502 |
Serial |
1094 |
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Permanent link to this record |
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Author |
Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Lebedev, O.I.; Turner, S.; Sada, C.; Depero, L.E.; Van Tendeloo, G.; Barreca, D. |
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Title |
Fluorine doped Fe2O3 nanostructures by a one-pot plasma-assisted strategy |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
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Volume |
3 |
Issue |
45 |
Pages |
23762-23768 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The present work reports on the synthesis of fluorine doped Fe2O3 nanomaterials by a single-step plasma enhanced-chemical vapor deposition (PE-CVD) strategy. In particular, Fe(hfa)2TMEDA (hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine) was used as molecular source for both Fe and F in Ar/O2 plasmas. The structure, morphology and chemical composition of the synthesized nanosystems were thoroughly analyzed by two-dimensional X-ray diffraction (XRD2), field emission-scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS) and transmission electron microscopy (TEM). A suitable choice of processing parameters enabled the selective formation of α-Fe2O3 nanomaterials, characterized by an homogeneous F doping, even at 100 °C. Interestingly, a simultaneous control of the system nanoscale organization and fluorine content could be achieved by varying the sole growth temperature. The tailored properties of the resulting materials can be favourably exploited for several technological applications, ranging from photocatalysis, to photoelectrochemical cells and gas sensing. |
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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 |
000326395800141 |
Publication Date |
2013-10-03 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
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ISSN |
2046-2069; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.108 |
Times cited |
23 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 3.108; 2013 IF: 3.708 |
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Call Number |
UA @ lucian @ c:irua:111091 |
Serial |
1237 |
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Permanent link to this record |
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Author |
Turner, S.; Lazar, S.; Freitag, B.; Egoavil, R.; Verbeeck, J.; Put, S.; Strauven, Y.; Van Tendeloo, G. |
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Title |
High resolution mapping of surface reduction in ceria nanoparticles |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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Volume |
3 |
Issue |
8 |
Pages |
3385-3390 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Surface reduction of ceria nano octahedra with predominant {111} and {100} type surfaces is studied using a combination of aberration-corrected Transmission Electron Microscopy (TEM) and spatially resolved electron energy-loss spectroscopy (EELS) at high energy resolution and atomic spatial resolution. The valency of cerium ions at the surface of the nanoparticles is mapped using the fine structure of the Ce M4,5 edge as a fingerprint. The valency of the surface cerium ions is found to change from 4+ to 3+ owing to oxygen deficiency (vacancies) close to the surface. The thickness of this Ce3+ shell is measured using atomic-resolution Scanning Transmission Electron Microscopy (STEM)-EELS mapping over a {111} surface (the predominant facet for this ceria morphology), {111} type surface island steps and {100} terminating planes. For the {111} facets and for {111} surface islands, the reduction shell is found to extend over a single fully reduced surface plane and 12 underlying mixed valency planes. For the {100} facets the reduction shell extends over a larger area of 56 oxygen vacancy-rich planes. This finding provides a plausible explanation for the higher catalytic activity of the {100} surface facets in ceria. |
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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 |
Cambridge |
Editor |
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Language |
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Wos |
000293521700057 |
Publication Date |
2011-06-30 |
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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 |
|
Series Issue |
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Edition |
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ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
7.367 |
Times cited |
127 |
Open Access |
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|
Notes |
Fwo |
Approved |
Most recent IF: 7.367; 2011 IF: 5.914 |
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Call Number |
UA @ lucian @ c:irua:90361UA @ admin @ c:irua:90361 |
Serial |
1458 |
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Permanent link to this record |
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Author |
Orlinskii, S.B.; Bogomolov, R.S.; Kiyamova, A.M.; Yavkin, B.V.; Mamin, G.M.; Turner, S.; Van Tendeloo, G.; Shiryaev, A.A.; Vlasov, I.I.; Shenderova, O. |
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Title |
Identification of substitutional nitrogen and surface paramagnetic centers in nanodiamond of dynamic synthesis by electron paramagnetic resonance |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Nanoscience and nanotechnology letters |
Abbreviated Journal |
Nanosci Nanotech Let |
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Volume |
3 |
Issue |
1 |
Pages |
63-67 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Production of nanodiamond particles containing substitutional nitrogen is important for a wide variety of advanced applications. In the current work nanodiamond particles synthesized from a mixture of graphite and hexogen were analyzed to determine the presence of substitutional nitrogen using pulsed electron paramagnetic resonance (EPR) spectroscopy. Nitrogen paramagnetic centers in the amount of 1.2 ppm have been identified. The spin relaxation characteristics for both nitrogen and surface defects are also reported. A new approach for efficient depletion of the strong non-nitrogen EPR signal in nanodiamond material by immersing nanodiamond particles into ice matrix is suggested. This approach allows an essential decrease of the spin relaxation time of the dominant non-nitrogen defects, while preserving the substitutional nitrogen spin relaxation time. |
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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 |
000293211200012 |
Publication Date |
2011-09-19 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
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ISSN |
1941-4900;1941-4919; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
1.889 |
Times cited |
14 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 1.889; 2011 IF: 0.528 |
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Call Number |
UA @ lucian @ c:irua:91943 |
Serial |
1548 |
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Permanent link to this record |
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Author |
Dubrovinsky, L.; Dubrovinskaia, N.; Prakapenka, V.B.; Abakumov, A.M. |
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Title |
Implementation of micro-ball nanodiamond anvils for high-pressure studies above 6 Mbar |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
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Volume |
3 |
Issue |
|
Pages |
1163-1167 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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|
Abstract |
Since invention of the diamond anvil cell technique in the late 1950s for studying materials at extreme conditions, the maximum static pressure generated so far at room temperature was reported to be about 400 GPa. Here we show that use of micro-semi-balls made of nanodiamond as second-stage anvils in conventional diamond anvil cells drastically extends the achievable pressure range in static compression experiments to above 600 GPa. Micro-anvils (10-50 mu m in diameter) of superhard nano-diamond (with a grain size below similar to 50 nm) were synthesized in a large volume press using a newly developed technique. In our pilot experiments on rhenium and gold we have studied the equation of state of rhenium at pressures up to 640 GPa and demonstrated the feasibility and crucial necessity of the in situ ultra high-pressure measurements for accurate determination of material properties at extreme conditions. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000313514100073 |
Publication Date |
2012-10-23 |
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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 |
2041-1723; |
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 |
150 |
Open Access |
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Notes |
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Approved |
Most recent IF: 12.124; 2012 IF: 10.015 |
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Call Number |
UA @ lucian @ c:irua:110134 |
Serial |
1563 |
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Permanent link to this record |
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Author |
Muguerra, H.; Pescheux, A.-C.; Meledin, A.; Van Tendeloo, G.; Soubeyroux, J.-L. |
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Title |
A La2−xGdxZr2O7layer deposited by chemical solution: a promising seed layer for the fabrication of high Jcand low cost coated conductors |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
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Volume |
3 |
Issue |
3 |
Pages |
11766-11772 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We deposited La2-xGdxZr2O7 seed layers by a chemical solution method on a Ni-5%W substrate to study the influence of these layers on the growth process of a 60 nm-thick La2Zr2O7 layer. We measured the performances of these new buffer layers integrated in a coated conductor with a 300 nm-thick Y0.5Gd0.5Ba2Cu3O7-x layer. For the seed layers{,} we considered two different gadolinium contents (x = 0.2 and x = 0.8) and three different thicknesses for these compositions (20 nm{,} 40 nm{,} and 60 nm). The most promising buffer layer stacks are those with 20 nm of the La1.8Gd0.2Zr2O7 layer or La1.2Gd0.8Zr2O7. Indeed the La2-xGdxZr2O7/La2Zr2O7 films are highly textured{,} similar to a 100 nm-thick La2Zr2O7 layer{,} but their roughness is four times lower. Moreover they contain less and smaller pores in the seed layer than a pure La2Zr2O7 layer. The surface of La2Zr2O7 is also homogenous and crystalline with an orientation deviation from the ideal ?011? (100) direction below 10[degree]. With the 20 nm La2-xGdxZr2O7 seed layers we obtain in the coated conductors an efficiently textured transfer with no gradual degradation from the substrate throughout the superconducting layer. The highest Tc and Jc values are achieved with the La1.8Gd0.2Zr2O7 layer and are{,} respectively{,} 91 K and 1.4 MA cm-2. This trend seems to be due to an improvement of the surface quality of the Ni5%W substrate by the addition of a thin seed layer. Our results offer the potential of the La2-xGdxZr2O7 seed layers as promising alternatives for the classic Ni-5%W/LZO/CeO2/YBCO architectures. |
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Wos |
000364826000024 |
Publication Date |
2015-10-21 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2050-7526;2050-7534; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.256 |
Times cited |
4 |
Open Access |
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Notes |
This work was performed within the framework of the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280438), funded by the European Union. The authors also thank L. Porcar and P. Chometon for superconducting transition temperature and critical current density measurements and P. Odier for fruitful discussion. |
Approved |
Most recent IF: 5.256; 2015 IF: 4.696 |
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Call Number |
c:irua:130181 |
Serial |
3968 |
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Author |
Van Aert, S.; De Backer, A.; Martinez, G.T.; den Dekker, A.J.; Van Dyck, D.; Bals, S.; Van Tendeloo, G. |
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Title |
Advanced electron crystallography through model-based imaging |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
IUCrJ |
Abbreviated Journal |
Iucrj |
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Volume |
3 |
Issue |
3 |
Pages |
71-83 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab; Engineering Management (ENM) |
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Abstract |
The increasing need for precise determination of the atomic arrangement of non-periodic structures in materials design and the control of nanostructures explains the growing interest in quantitative transmission electron microscopy. The aim is to extract precise and accurate numbers for unknown structure parameters including atomic positions, chemical concentrations and atomic numbers. For this purpose, statistical parameter estimation theory has been shown to provide reliable results. In this theory, observations are considered purely as data planes, from which structure parameters have to be determined using a parametric model describing the images. As such, the positions of atom columns can be measured with a precision of the order of a few picometres, even though the resolution of the electron microscope is still one or two orders of magnitude larger. Moreover, small differences in average atomic number, which cannot be distinguished visually, can be quantified using high-angle annular dark-field scanning transmission electron microscopy images. In addition, this theory allows one to measure compositional changes at interfaces, to count atoms with single-atom sensitivity, and to reconstruct atomic structures in three dimensions. This feature article brings the reader up to date, summarizing the underlying theory and highlighting some of the recent applications of quantitative model-based transmisson electron microscopy. |
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Wos |
000368590900010 |
Publication Date |
2015-11-13 |
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Series Issue |
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Edition |
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ISSN |
2052-2525; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.793 |
Times cited |
30 |
Open Access |
OpenAccess |
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Notes |
The authors gratefully acknowledge the Research Foundation Flanders (FWO, Belgium) for funding and for a PhD grant to ADB. The research leading to these results has received funding from the European Union 7th Framework Program (FP7/20072013) under grant agreement No. 312483 (ESTEEM2). SB and GVT acknowledge the European Research Council under the 7th Framework Program (FP7), ERC grant No. 335078 – COLOURATOMS and ERC grant No. 246791 – COUNTATOMS.; esteem2jra2; ECASSara; (ROMEO:green; preprint:; postprint:can ; pdfversion:can); |
Approved |
Most recent IF: 5.793 |
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Call Number |
c:irua:129589 c:irua:129589 |
Serial |
3965 |
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Permanent link to this record |