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Records |
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Author |
Sun, M.; Rousse, G.; Abakumov, A.M.; Saubanere, M.; Doublet, M.-L.; Rodriguez-Carvajal, J.; Van Tendeloo, G.; Tarascon, J.-M. |
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Title |
Li2Cu2O(SO4)2: a possible electrode for sustainable Li-based batteries showing a 4.7 V redox activity vs Li+/Li0 |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
27 |
Issue |
27 |
Pages |
3077-3087 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract  |
Li-ion batteries rely on the use of insertion positive electrodes with performances scaling with the redox potential of the 31) metals accompanying Liuptake/removal. Although not commonly studied, the Cu2+/Cu3+ redox potential has been predicted from theoretical calculations to possibly offer a high operating voltage redox couple. We herein report the synthesis and crystal structure of a hitherto-unknown oxysulfate phase, Li2Cu2O(SO4)(2), which contains infinite edgesharing CuO4 chains and presents attractive electrochemical redox activity with respect to Li+/Li, namely amphoteric characteristics. Li2Cu2O(SO4)(2) shows redox activity at 4.7 V vs Li+/Li corresponding to the oxidation of Cu2+ to Cu3+ enlisting ligand holes and associated with the reversible uptake-removal of 0.3 Li. Upon reduction, this compound reversibly uptakes similar to 2 Li at an average potential of about 2.5 V vs Li+/Li, associated with the Cu2+/Cu+ redox couple. The mechanism of the reactivity upon reduction is discussed in detail, with particular attention to the occasional appearance of an oscillation wave in the discharge profile. Our work demonstrates that Cu-based compounds can indeed be fertile scientific ground in the search for new high-energy-density electrodes. |
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Wos |
000353865800043 |
Publication Date |
2015-03-25 |
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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 |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2015 IF: 8.354 |
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Call Number |
c:irua:126061 |
Serial |
3541 |
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| Permanent link to this record |
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Author |
McCalla, E.; Sougrati, M.T.; Rousse, G.; Berg, E.J.; Abakumov, A.; Recham, N.; Ramesha, K.; Sathiya, M.; Dominko, R.; Van Tendeloo, G.; Novák, P.; Tarascon, J.M.; |
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Title |
Understanding the roles of anionic redox and oxygen release during electrochemical cycling of lithium-rich layered Li4FeSbO6 |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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| |
Volume |
137 |
Issue |
137 |
Pages |
4804-4814 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Li-rich oxides continue to be of immense interest as potential next generation Li-ion battery positive electrodes, and yet the role of oxygen during cycling is still poorly understood. Here, the complex electrochemical behavior of Li4FeSbO6 materials is studied thoroughly with a variety of methods. Herein, we show that oxygen release occurs at a distinct voltage plateau from the peroxo/superoxo formation making this material ideal for revealing new aspects of oxygen redox processes in Li-rich oxides. Moreover, we directly demonstrate the limited reversibility of the oxygenated species (O-2(n-); n = 1, 2, 3) for the first time. We also find that during charge to 4.2 V iron is oxidized from +3 to an unusual +4 state with the concomitant formation of oxygenated species. Upon further charge to 5.0 V, an oxygen release process associated with the reduction of iron +4 to +3 is present, indicative of the reductive coupling mechanism between oxygen and metals previously reported. Thus, in full state of charge, lithium removal is fully compensated by oxygen only, as the iron and antimony are both very close to their pristine states. Besides, this charging step results in complex phase transformations that are ultimately destructive to the crystallinity of the material. Such findings again demonstrate the vital importance of fully understanding the behavior of oxygen in such systems. The consequences of these new aspects of the electrochemical behavior of lithium-rich oxides are discussed in detail. |
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Corporate Author |
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Place of Publication |
Washington, D.C. |
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Language |
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Wos |
000353177100036 |
Publication Date |
2015-03-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0002-7863;1520-5126; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.858 |
Times cited |
86 |
Open Access |
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Notes |
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Approved |
Most recent IF: 13.858; 2015 IF: 12.113 |
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Call Number |
c:irua:126019 |
Serial |
3805 |
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Author |
Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Kuznetsov, A.S.; Chibotaru, L.F.; Baranov, A.N.; Van Tendeloo, G.; Moshchalkov, V.V. |
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Title |
Quantum cutting in Li (770 nm) and Yb (1000 nm) co-dopant emission bands by energy transfer from the ZnO nano-crystalline host |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Optics express |
Abbreviated Journal |
Opt Express |
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Volume |
19 |
Issue |
17 |
Pages |
15955-15964 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Li-Yb co-doped nano-crystalline ZnO has been synthesized by a method of thermal growth from the salt mixtures. X-ray diffraction, transmission electron microscopy, atomic absorption spectroscopy and optical spectroscopy confirm the doping and indicate that the dopants may form Li-Li and Yb3+-Li based nanoclusters. When pumped into the conduction and exciton absorption bands of ZnO between 250 to 425 nm, broad emission bands of about 100 nm half-height-width are excited around 770 and 1000 nm, due to Li and Yb dopants, respectively. These emission bands are activated by energy transfer from the ZnO host mostly by quantum cutting processes, which generate pairs of quanta in Li (770 nm) and Yb (1000 nm) emission bands, respectively, out of one quantum absorbed by the ZnO host. These quantum cutting phenomena have great potential for application in the down-conversion layers coupled to the Si solar cells. |
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Corporate Author |
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Place of Publication |
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Wos |
000293894900033 |
Publication Date |
2011-08-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1094-4087; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.307 |
Times cited |
19 |
Open Access |
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Notes |
FWO; Methusalem |
Approved |
Most recent IF: 3.307; 2011 IF: 3.587 |
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Call Number |
UA @ lucian @ c:irua:92428 |
Serial |
2776 |
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Author |
Hamelet, S.; Casas-Cabanas, M.; Dupont, L.; Davoisne, C.; Tarascon, J.M.; Masquelier, C. |
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Title |
Existence of superstructures due to large amounts of Fe vacancies in the LiFePO4-type framework |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
23 |
Issue |
1 |
Pages |
32-38 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LiFePO4 has been under intense scrutiny over the past decade because it stands as an attractive positive electrode material for the next generation of Li-ion batteries to power electric vehicles and hybrid electric vehicles, hence the importance of its thermal behavior. The reactivity of LiFePO4 with air at moderate temperatures is shown to be dependent on its particle size. For nanosized materials, a progressive displacement of Fe from the core structure leading to a composite made of nanosize Fe2O3 and highly defective, oxidized LixFeyPO4 compositions, among which the “ideal” formula LiFe2/3PO4. Herein we report, from both temperature-controlled X-ray diffraction and electronic diffraction microscopy, that these off-stoichiometry olivine-type compounds show a defect ordering resulting in the formation of a superstructure. Such a finding shows striking similarities with the temperature-driven oxidation of fayalite Fe2SiO4 (another olivine) to structurally defective laihunite, reported in the literature three decades ago. |
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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 |
Washington, D.C. |
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Language |
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Wos |
000285726900007 |
Publication Date |
2010-12-14 |
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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 |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
30 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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Call Number |
UA @ lucian @ c:irua:105605 |
Serial |
1130 |
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Author |
Wang, L.; Li, Y.; Yang, X.-Y.; Zhang, B.-B.; Ninane, N.; Busscher, H.J.; Hu, Z.-Y.; Delneuville, C.; Jiang, N.; Xie, H.; Van Tendeloo, G.; Hasan, T.; Su, B.-L. |
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Title |
Single-cell yolk-shell nanoencapsulation for long-term viability with size-dependent permeability and molecular recognition |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
National Science Review |
Abbreviated Journal |
Natl Sci Rev |
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Volume |
8 |
Issue |
4 |
Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Like nanomaterials, bacteria have been unknowingly used for centuries. They hold significant economic potential for fuel and medicinal compound production. Their full exploitation, however, is impeded by low biological activity and stability in industrial reactors. Though cellular encapsulation addresses these limitations, cell survival is usually compromised due to shell-to-cell contacts and low permeability. Here, we report ordered packing of silica nanocolloids with organized, uniform and tunable nanoporosities for single cyanobacterium nanoencapsulation using protamine as an electrostatic template. A space between the capsule shell and the cell is created by controlled internalization of protamine, resulting in a highly ordered porous shell-void-cell structure formation. These unique yolk-shell nano structures provide long-term cell viability with superior photosynthetic activities and resistance in harsh environments. In addition, engineering the colloidal packing allows tunable shell-pore diameter for size-dependent permeability and introduction of new functionalities for specific molecular recognition. Our strategy could significantly enhance the activity and stability of cyanobacteria for various nanobiotechnological applications. |
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Corporate Author |
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Place of Publication |
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Wos |
000651827200002 |
Publication Date |
2020-05-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2095-5138 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.843 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 8.843 |
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Call Number |
UA @ admin @ c:irua:179085 |
Serial |
6885 |
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Author |
Fedotov, S.S.; Kuzovchikov, S.M.; Khasanova, N.R.; Drozhzhin, O.A.; Filimonov, D.S.; Karakulina, O.M.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V. |
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Title |
Synthesis, structure and electrochemical properties of LiNaCo0.5Fe0.5PO4F fluoride-phosphate |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
242 |
Issue |
242 |
Pages |
70-77 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LiNaCo 0.5 Fe 0.5 PO 4 F fluoride-phosphate was synthesized via conventional solid-state and novel freeze-drying routes. The crystal structure was refined based on neutron powder diffraction (NPD) data and validated by electron diffraction (ED) and high-resolution transmission electron microscopy (HRTEM). The alkali ions are ordered in LiNaCo 0.5 Fe 0.5 PO 4 F and the transition metals jointly occupy the same crystallographic sites. The oxidation state and oxygen coordination environment of the Fe atoms were verified by 57 Fe Mössbauer spectroscopy. Electrochemical tests of the LiNaCo 0.5 Fe 0.5 PO 4 F cathode material demonstrated a reversible activity of the Fe 3+ /Fe 2+ redox couple at the electrode potential near 3.4 V and minor activity of the Co 3+ /Co 2+ redox couple over 5 V vs Li/Li + . The material exhibits a good capacity retention in the 2.4÷4.6 V vs Li/Li + potential range with the delivered discharge capacity of more than 82% (theo.) regarding Fe 3+ /Fe 2+ . |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000383304900010 |
Publication Date |
2016-02-27 |
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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 |
0022-4596 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
1 |
Open Access |
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Notes |
The authors kindly thank Dr. O. A. Shlyakhtin for the assistance in the freeze-drying synthesis. We are grateful to the Laboratory for Neutron Scattering and Imaging (NLS) at the Paul Scherrer Institut (Villigen, Switzerland) for granting beam time at the HRPT diffractometer and to Dr. D. V. Sheptyakov for the technical support during the experiment. The work was partly supported by Russian Foundation for Basic Research (RFBR grant 13-03-00495a, 14-29-04064 ofim, 16-33-01131 mola), Skoltech Center for Electrochemical Energy Storage and Moscow State University Development Program up to 2020. J. Hadermann, O.M. Karakulina and A.M. Abakumov acknowledge support from FWO under grant G040116N. |
Approved |
Most recent IF: 2.299 |
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Call Number |
c:irua:133776 |
Serial |
4075 |
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| Permanent link to this record |
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Author |
Gong, X.; Marmy, P.; Volodin, A.; Amin-Ahmadi, B.; Qin, L.; Schryvers, D.; Gavrilov, S.; Stergar, E.; Verlinden, B.; Wevers, M.; Seefeldt, M. |
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Title |
Multiscale investigation of quasi-brittle fracture characteristics in a 9Cr–1Mo ferritic–martensitic steel embrittled by liquid lead–bismuth under low cycle fatigue |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Corrosion science |
Abbreviated Journal |
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Volume |
102 |
Issue |
102 |
Pages |
137-152 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Liquid metal embrittlement (LME) induced quasi-brittle fracture characteristics of a 9Cr–1Mo ferritic–martensitic steel (T91) after fatigue cracking in lead–bismuth eutectic (LBE) have been investigated at various length scales. The results show that the LME fracture morphology is primarily characterized by quasi-brittle translath flat regions partially covered by nanodimples, shallow secondary cracks propagating along the martensitic lath boundaries as well as tear ridges covered by micro dimples. These diverse LME fracture features likely indicate a LME mechanism involving multiple physical processes, such as weakening induced interatomic decohesion at the crack tip and plastic shearing induced nano/micro voiding in the plastic zone. |
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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 |
000367275700014 |
Publication Date |
2015-10-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0010938X |
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 |
16 |
Open Access |
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Notes |
The work is financially supported by the MYRRHA project,SCK•CEN, Belgium and partly funded by the European AtomicEnergy Community’s (Euratom) Seventh Framework ProgrammeFP7/2007-2013 under grant agreement No. 604862 (MatISSEproject) and in the framework of the EERA (European EnergyResearch Alliance) Joint Programme on Nuclear Materials. Dr. TomVan der Donck (KU Leuven) is acknowledged for the EBSD mea-surements. The authors are grateful to Dr. Van Renterghem Wouter(SCK•CEN) for fruitful discussion of the TEM results. Xing Gongsincerely acknowledges valuable suggestions from Dr. S.P. Lynch(Defence Science and Technology Organisation and Monash Uni-versity, Melbourne, Australia). |
Approved |
Most recent IF: NA |
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Call Number |
c:irua:129997 |
Serial |
4013 |
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| Permanent link to this record |
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Author |
McCalla, E.; Abakumov, A.M.; Saubanere, M.; Foix, D.; Berg, E.J.; Rousse, G.; Doublet, M.-L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Dominko, R.; Tarascon, J.-M. |
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Title |
Visualization of O-O peroxo-like dimers in high-capacity layered oxides for Li-ion batteries |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Science |
Abbreviated Journal |
Science |
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Volume |
350 |
Issue |
350 |
Pages |
1516-1521 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Lithium-ion (Li-ion) batteries that rely on cationic redox reactions are the primary energy source for portable electronics. One pathway toward greater energy density is through the use of Li-rich layered oxides. The capacity of this class of materials (>270 milliampere hours per gram) has been shown to be nested in anionic redox reactions, which are thought to form peroxo-like species. However, the oxygen-oxygen (O-O) bonding pattern has not been observed in previous studies, nor has there been a satisfactory explanation for the irreversible changes that occur during first delithiation. By using Li2IrO3 as a model compound, we visualize the O-O dimers via transmission electron microscopy and neutron diffraction. Our findings establish the fundamental relation between the anionic redox process and the evolution of the O-O bonding in layered oxides. |
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Address |
College de France, Chimie du Solide et de l'Energie, FRE 3677, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France. ALISTORE-European Research Institute, FR CNRS 3104, 80039 Amiens, France. Reseau sur le Stockage Electrochimique de l'Energie (RS2E), FR CNRS 3459, France. Sorbonne Universites-UPMC Univ Paris 06, 4 Place Jussieu, F-75005 Paris, France. jean-marie.tarascon@college-de-france.fr |
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Publisher |
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Place of Publication |
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Language |
English |
Wos |
000366591100056 |
Publication Date |
2015-12-17 |
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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 |
0036-8075 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
37.205 |
Times cited |
281 |
Open Access |
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Notes |
E.M. thanks the Fonds de Recherche du Québec–Nature et Technologies and ALISTORE–European Research Institute for funding this work, as well as the European community I3 networks for funding the neutron scattering research trip. This work was also funded by the Slovenian Research Agency research program P2-0148. This work is partially based on experiments performed at the Institut Laue Langevin. We thank J. Rodriguez-Carvajal for help with neutron scattering experiments and for fruitful discussions. We also thank M. T. Sougrati for performing the Sn-Mössbauer measurements. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract no. DE-AC02- 06CH11357. M.S. and M.-L.D. acknowledge high-performance computational resources from GENCI-CCRT/CINES (grant cmm6691). J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014-2020)/ERC Grant-Project670116-ARPEMA. |
Approved |
Most recent IF: 37.205; 2015 IF: 33.611 |
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Call Number |
c:irua:130202 |
Serial |
4005 |
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Author |
Pearce, P.E.; Perez, A.J.; Rousse, G.; Saubanère, M.; Batuk, D.; Foix, D.; McCalla, E.; Abakumov, A.M.; Van Tendeloo, G.; Doublet, M.-L.; Tarascon, J.-M. |
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Title |
Evidence for anionic redox activity in a tridimensional-ordered Li-rich positive electrode β-Li2IrO3 |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
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Volume |
16 |
Issue |
5 |
Pages |
580-586 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Lithium-ion battery cathode materials have relied on cationic redox reactions until the recent discovery of anionic redox activity in Li-rich layered compounds which enables capacities as high as 300 mAh g(-1). In the quest for new high-capacity electrodes with anionic redox, a still unanswered question was remaining regarding the importance of the structural dimensionality. The present manuscript provides an answer. We herein report on a beta-Li2IrO3 phase which, in spite of having the Ir arranged in a tridimensional (3D) framework instead of the typical two-dimensional (2D) layers seen in other Li-rich oxides, can reversibly exchange 2.5 e(-) per Ir, the highest value ever reported for any insertion reaction involving d-metals. We show that such a large activity results from joint reversible cationic (Mn+) and anionic (O-2)(n-) redox processes, the latter being visualized via complementary transmission electron microscopy and neutron diffraction experiments, and confirmed by density functional theory calculations. Moreover, beta-Li2IrO3 presents a good cycling behaviour while showing neither cationic migration nor shearing of atomic layers as seen in 2D-layered Li-rich materials. Remarkably, the anionic redox process occurs jointly with the oxidation of Ir4+ at potentials as low as 3.4 V versus Li+/Li-0, as equivalently observed in the layered alpha-Li2IrO3 polymorph. Theoretical calculations elucidate the electrochemical similarities and differences of the 3D versus 2D polymorphs in terms of structural, electronic and mechanical descriptors. Our findings free the structural dimensionality constraint and broaden the possibilities in designing high-energy-density electrodes for the next generation of Li-ion batteries. |
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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 |
000400004200018 |
Publication Date |
2017-02-27 |
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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 |
1476-1122 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
39.737 |
Times cited |
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Open Access |
Not_Open_Access |
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| |
Notes |
The authors thank Q. Jacquet for fruitful discussions and V. Pomjakushin for his valuable help in neutron diffraction experiments. This work is based on experiments performed at the Swiss Spallation Neutron Source SINQ, Paul Scherrer Institute, Villigen, Switzerland. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is greatly acknowledged. J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014)/ERC Grant-Project 670116-ARPEMA. E.M. acknowledges financial support from the Fonds de Recherche du Quebec-Nature et Technologies. |
Approved |
Most recent IF: 39.737 |
|
| |
Call Number |
EMAT @ emat @c:irua:147502 |
Serial |
4773 |
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| Permanent link to this record |
| |
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| |
|
Author |
Bercx, M.; Slap, L.; Partoens, B.; Lamoen, D. |
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| |
Title |
First-Principles Investigation of the Stability of the Oxygen Framework of Li-Rich Battery Cathodes |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
MRS advances |
Abbreviated Journal |
MRS Adv. |
|
| |
Volume |
4 |
Issue |
14 |
Pages |
813-820 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
| |
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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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 |
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 |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
2059-8521 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
3 |
Open Access |
Not_Open_Access: Available from 22.02.2020
|
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| |
Notes |
We acknowledge the financial support of FWO-Vlaanderen through project G040116N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: NA |
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| |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:160121 |
Serial |
5179 |
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| Permanent link to this record |
| |
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| |
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Author |
McCalla, E.; Prakash, A.S.; Berg, E.; Saubanere, M.; Abakumov, A.M.; Foix, D.; Klobes, B.; Sougrati, M.T.; Rousse, G.; Lepoivre, F.; Mariyappan, S.; Doublet, M.L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Hermann, R.P.; Tarascon, J.M.; |
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| |
Title |
Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of the electrochemical society |
Abbreviated Journal |
J Electrochem Soc |
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| |
Volume |
162 |
Issue |
162 |
Pages |
A1341-A1351 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved. |
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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 |
New York, N.Y. |
Editor |
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Language |
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Wos |
000355643700030 |
Publication Date |
2015-04-29 |
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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 |
0013-4651;1945-7111; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.259 |
Times cited |
23 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.259; 2015 IF: 3.266 |
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| |
Call Number |
c:irua:126445 |
Serial |
2903 |
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| Permanent link to this record |
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Author |
Ulu Okudur, F.; Batuk, M.; Hadermann, J.; Safari, M.; De Sloovere, D.; Kumar Mylavarapu, S.; Joos, B.; D'Haen, J.; Van Bael, M.K.; Hardy, A. |
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Title |
Solution-gel-based surface modification of LiNi0.5Mn1.5O4-δ with amorphous Li-Ti-O coating |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
RSC advances |
Abbreviated Journal |
|
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| |
Volume |
13 |
Issue |
47 |
Pages |
33146-33158 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
LNMO (LiNi0.5Mn1.5O4-delta) is a high-energy density positive electrode material for lithium ion batteries. Unfortunately, it suffers from capacity loss and impedance rise during cycling due to electrolyte oxidation and electrode/electrolyte interface instabilities at high operating voltages. Here, a solution-gel synthesis route was used to coat 0.5-2.5 mu m LNMO particles with amorphous Li-Ti-O (LTO) for improved Li conduction, surface structural stability and cyclability. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) analysis coupled with energy dispersive X-ray (EDX) showed Ti-rich amorphous coatings/islands or Ti-rich spinel layers on many of the LTO-modified LNMO facets, with a thickness varying from about 1 to 10 nm. The surface modification in the form of amorphous islands was mostly possible on high-energy crystal facets. Physicochemical observations were used to propose a molecular mechanism for the surface modification, combining insights from metalorganic chemistry with the crystallographic properties of LNMO. The improvements in functional properties were investigated in half cells. The cell impedance increased faster for the bare LNMO compared to amorphous LTO modified LNMO, resulting in R-ct values as high as 1247 Omega (after 1000 cycles) for bare LNMO, against 216 Omega for the modified material. At 10C, the modified material boosted a 15% increase in average discharge capacity. The improvements in electrochemical performance were attributed to the increase in electrochemically active surface area, as well as to improved HF-scavenging, resulting in the formation of protective byproducts, generating a more stable interface during prolonged cycling. |
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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 |
001102666700001 |
Publication Date |
2023-11-09 |
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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 |
2046-2069 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
|
Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:202091 |
Serial |
9096 |
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| Permanent link to this record |
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Author |
Zelaya, E.; Esquivel, M.R.; Schryvers, D. |
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| |
Title |
Evolution of the phase stability of NiAl under low energy ball milling |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Advanced powder technology |
Abbreviated Journal |
Adv Powder Technol |
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| |
Volume |
24 |
Issue |
6 |
Pages |
1063-1069 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Low energy mechanical alloying of Ni35 at.%Al and Ni40 at.%Al material was performed and the resulting structures were investigated by XRD and TEM. The final intermetallics observed consist of two phases, NiAl(B2) and Ni3Al while 7R and 3R martensite was observed in post-annealed samples. Different integrated milling times were associated to the intermetallic consolidation and initial blend dissociation. |
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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 |
Zeist |
Editor |
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Language |
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Wos |
000339175000024 |
Publication Date |
2013-03-30 |
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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 |
0921-8831; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.659 |
Times cited |
10 |
Open Access |
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| |
Notes |
Fwo |
Approved |
Most recent IF: 2.659; 2013 IF: 1.642 |
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Call Number |
UA @ lucian @ c:irua:107345 |
Serial |
1102 |
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| Permanent link to this record |
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Author |
Berends, A.C.; Rabouw, F.T.; Spoor, F.C.M.; Bladt, E.; Grozema, F.C.; Houtepen, A.J.; Siebbeles, L.D.A.; de Donega, C.M. |
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Title |
Radiative and nonradiative recombination in CuInS2 nanocrystals and CuInS2-based core/shell nanocrystals |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
The journal of physical chemistry letters |
Abbreviated Journal |
J Phys Chem Lett |
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| |
Volume |
7 |
Issue |
7 |
Pages |
3503-3509 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Luminescent copper indium sulfide (CIS) nanocrystals are a potential solution to the toxicity issues associated with Cd- and Pb-based nanocrystals. However, the development of high-quality CIS nanocrystals has been complicated by insufficient knowledge of the electronic structure and of the factors that lead to luminescence quenching. Here we investigate the exciton decay pathways in CIS nanocrystals using time resolved photoluminescence and transient absorption spectroscopy. Core-only CIS nanocrystals with low quantum yield are compared to core/shell nanocrystals (CIS/ZnS and CIS/CdS) with higher quantum yield. Our measurements support the model of photoluminescence by radiative recombination of a conduction band electron with a localized hole. Moreover, we find that photoluminescence quenching in low-quantum-yield nanocrystals involves initially uncoupled decay pathways for the electron and hole. The electron decay pathway determines whether the exciton recombines radiatively or nonradiatively. The development of high-quality CIS nanocrystals should therefore focus on the elimination of electron traps. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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| |
Language |
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Wos |
000382603300037 |
Publication Date |
2016-08-23 |
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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 |
1948-7185 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.353 |
Times cited |
67 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.353 |
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| |
Call Number |
UA @ lucian @ c:irua:135715 |
Serial |
4308 |
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| Permanent link to this record |
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Author |
Venturi, F.; Calizzi, M.; Bals, S.; Perkisas, T.; Pasquini, L. |
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Title |
Self-assembly of gas-phase synthesized magnesium nanoparticles on room temperature substrates |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Materials research express |
Abbreviated Journal |
Mater Res Express |
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| |
Volume |
2 |
Issue |
2 |
Pages |
015007 |
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| |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Magnesium nanoparticles (NPs) with initial size in the 10-50 nmrange were synthesized by inert gas condensation under helium flow and deposited on room temperature substrates. The morphology and crystal structure of the NPs ensemble were investigated as a function of the deposition time by complementary electron microscopy techniques, including high resolution imaging and chemical mapping. With increasing amount of material, strong coarsening phenomena were observed at room temperature: small NPs disappeared while large faceted NPs developed, leading to a 5-fold increase of the average NPs size within a few minutes. The extent of coarsening and the final morphology depended also on the nature of the substrate. Furthermore, large single-crystal NPs were seen to arise from the self-organization of primary NPs units, providing a mechanism for crystal growth. The dynamics of the self-assembly process involves the basic steps of NPs sticking, diffusion on substrate, coordinated rotation and attachment/coalescence. Key features are the surface energy anisotropy, reflected by the faceted shape of the NPs, and the low melting point of the material. The observed phenomena have strong implications in relation to the synthesis and stability of nanostructures based on Mg or other elements with similar features. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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| |
Language |
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Wos |
000369978500007 |
Publication Date |
2014-12-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
2053-1591 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.068 |
Times cited |
14 |
Open Access |
Not_Open_Access |
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| |
Notes |
; Financial support by COST Action MP1103 'Nanostructured Materials for Solid-State Hydrogen Storage' is gratefully acknowledged. ; |
Approved |
Most recent IF: 1.068; 2015 IF: NA |
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Call Number |
UA @ lucian @ c:irua:132275 |
Serial |
4240 |
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| Permanent link to this record |
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Author |
Guzzinati, G.; Béché, A.; McGrouther, D.; Verbeeck, J. |
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Title |
Prospects for out-of-plane magnetic field measurements through interference of electron vortex modes in the TEM |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of optics |
Abbreviated Journal |
J Optics-Uk |
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| |
Volume |
21 |
Issue |
12 |
Pages |
124002 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Magnetic field mapping in transmission electron microscopy is commonplace, but all conventional methods provide only a projection of the components of the magnetic induction perpendicular to the electron trajectory. Recent experimental advances with electron vortices have shown that it is possible to map the out of plane magnetic induction in a TEM setup via interferometry with a specifically prepared electron vortex state carrying high orbital angular momentum (OAM). The method relies on the Aharonov?Bohm phase shift that the electron undergoes when going through a longitudinal field. Here we show how the same effect naturally occurs for any electron wave function, which can always be described as a superposition of OAM modes. This leads to a clear connection between the occurrence of high-OAM partial waves and the amount of azimuthal rotation in the far field angular distribution of the beam. We show that out of plane magnetic field measurement can thus be obtained with a much simpler setup consisting of a ring-like aperture with azimuthal spokes. We demonstrate the experimental setup and explore the achievable sensitivity of the magnetic field measurement. |
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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 |
000499367800001 |
Publication Date |
2019-10-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2040-8978 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.741 |
Times cited |
3 |
Open Access |
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| |
Notes |
The authors thank V Grillo and T Harvey for interesting and fruitful discussion. GG acknowledges support from a postdoctoral fellow-ship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. AB acknowledges funding from FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy'). DM gratefully acknowledges funding of the FEBID capability through joint funding by University of Glasgow & EPSRC through a Strategic Equipment Grant (EP/P001483/1). |
Approved |
Most recent IF: 1.741 |
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| |
Call Number |
UA @ admin @ c:irua:165116 |
Serial |
6319 |
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| Permanent link to this record |
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Author |
Crippa, F.; Rodriguez-Lorenzo, L.; Hua, X.; Goris, B.; Bals, S.; Garitaonandia, J.S.; Balog, S.; Burnand, D.; Hirt, A.M.; Haeni, L.; Lattuada, M.; Rothen-Rutishauser, B.; Petri-Fink, A. |
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Title |
Phase transformation of superparamagnetic iron oxide nanoparticles via thermal annealing : implications for hyperthermia applications |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
ACS applied nano materials |
Abbreviated Journal |
|
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| |
Volume |
2 |
Issue |
2 |
Pages |
4462-4470 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Magnetic hyperthermia has the potential to play an important role in cancer therapy and its efficacy relies on the nanomaterials selected. Superparamagnetic iron oxide nanoparticles (SPIONs) are excellent candidates due to the ability of producing enough heat to kill tumor cells by thermal ablation. However, their heating properties depend strongly on crystalline structure and size, which may not be controlled and tuned during the synthetic process; therefore, a postprocessing is needed. We show how thermal annealing can be simultaneously coupled with ligand exchange to stabilize the SPIONs in polar solvents and to modify their crystal structure, which improves hyperthermia behavior. Using high-resolution transmission electron microscopy, X-ray diffraction, Mossbauer spectroscopy, vibrating sample magnetometry, and lock-in thermography, we systematically investigate the impact of size and ligand exchange procedure on crystallinity, their magnetism, and heating ability. We describe a valid and simple approach to optimize SPIONs for hyperthermia by carefully controlling the size, colloidal stability, and crystallinity. |
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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 |
000477917700048 |
Publication Date |
2019-06-27 |
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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 |
|
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
18 |
Open Access |
Not_Open_Access |
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| |
Notes |
; This work was supported by the Swiss National Science Foundation through the National Center of Competence in Research Bio-Inspired Materials, the Adolphe Merkle Foundation, the University of Fribourg, and the European Society for Molecular Imaging (Grant E141200643). ; |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ admin @ c:irua:161927 |
Serial |
5393 |
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| Permanent link to this record |
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Author |
Kleibert, A.; Balan, A.; Yanes, R.; Derlet, P.M.; Vaz, C.A.F.; Timm, M.; Fraile Rodríguez, A.; Béché, A.; Verbeeck, J.; Dhaka, R.S.; Radovic, M.; Nowak, U.; Nolting, F. |
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Title |
Direct observation of enhanced magnetism in individual size- and shape-selected 3d transition metal nanoparticles |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
95 |
Issue |
95 |
Pages |
195404 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Magnetic nanoparticles are critical building blocks for future technologies ranging from nanomedicine to spintronics. Many related applications require nanoparticles with tailored magnetic properties. However, despite significant efforts undertaken towards this goal, a broad and poorly understood dispersion of magnetic properties is reported, even within monodisperse samples of the canonical ferromagnetic 3d transition metals. We address this issue by investigating the magnetism of a large number of size- and shape-selected, individual nanoparticles of Fe, Co, and Ni using a unique set of complementary characterization techniques. At room temperature, only superparamagnetic behavior is observed in our experiments for all Ni nanoparticles within the investigated sizes, which range from 8 to 20 nm. However, Fe and Co nanoparticles can exist in two distinct magnetic states at any size in this range: (i) a superparamagnetic state, as expected from the bulk and surface anisotropies known for the respective materials and as observed for Ni, and (ii) a state with unexpected stable magnetization at room temperature. This striking state is assigned to significant modifications of the magnetic properties arising from metastable lattice defects in the core of the nanoparticles, as concluded by calculations and atomic structural characterization. Also related with the structural defects, we find that the magnetic state of Fe and Co nanoparticles can be tuned by thermal treatment enabling one to tailor their magnetic properties for applications. This paper demonstrates the importance of complementary single particle investigations for a better understanding of nanoparticle magnetism and for full exploration of their potential for applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
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| |
Language |
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Wos |
000400665300002 |
Publication Date |
2017-05-05 |
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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 |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
OpenAccess |
|
| |
Notes |
We thank A. Weber, R. Schelldorfer, and J. Krbanjevic (Paul Scherrer Institut) for technical assistance. This paper was supported by the Swiss Nanoscience Institute, University of Basel. A.F.R. acknowledges support from the MICIIN “Ramón y Cajal” Programme. A.B. and J.V. acknowledge funding from the European Union under the European Research Council (ERC) Starting Grant No. 278510 VORTEX and under a contract for Integrated Infrastructure Initiative ESTEEM2 No. 312483. R.Y. and U.N. thank the Deutsche Forschungsgemeinschaft for financial support via Sonderforschungsbereich 1214. Part of this work was performed at the Surface/Interface: Microscopy (SIM) beamline of the Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland. |
Approved |
Most recent IF: 3.836 |
|
| |
Call Number |
EMAT @ emat @ c:irua:143634UA @ admin @ c:irua:143634 |
Serial |
4575 |
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| Permanent link to this record |
| |
|
| |
|
Author |
Breynaert, E.; Emmerich, J.; Mustafa, D.; Bajpe, S.R.; Altantzis, T.; Van Havenbergh, K.; Taulelle, F.; Bals, S.; Van Tendeloo, G.; Kirschhock, C.E.A.; Martens, J.A.; |
|
| |
Title |
Enhanced self-assembly of metal oxides and metal-organic frameworks from precursors with magnetohydrodynamically induced long-lived collective spin states |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
|
| |
Volume |
26 |
Issue |
30 |
Pages |
5173-5178 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Magneto-hydrodynamic generation of long-lived collective spin states and their impact on crystal morphology is demonstrated for three different, technologically relevant materials: COK-16 metal organic framework, manganese oxide nanotubes, and vanadium oxide nano-scrolls. |
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Address |
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Corporate Author |
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Thesis |
|
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| |
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
|
| |
Language |
|
Wos |
000340546300015 |
Publication Date |
2014-06-02 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0935-9648; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
19.791 |
Times cited |
7 |
Open Access |
OpenAccess |
|
| |
Notes |
IAP-PAI; Marie Curie IEF; 262348 ESMI; 335078 COLOURATOM; 246791 COUNTATOMS; IWT; Methusalem; FWO; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 19.791; 2014 IF: 17.493 |
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| |
Call Number |
UA @ lucian @ c:irua:118827 |
Serial |
1053 |
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| Permanent link to this record |
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| |
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Author |
Maignan, A.; Martin, C.; Singh, K.; Simon, C.; Lebedev, O.I.; Turner, S. |
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| |
Title |
From spin induced ferroelectricity to dipolar glasses : spinel chromites and mixed delafossites |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
|
| |
Volume |
195 |
Issue |
|
Pages |
41-49 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Magnetoelectric multiferroics showing coupling between polarization and magnetic order are attracting much attention. For instance, they could be used in memory devices. Metal-transition oxides are provided several examples of inorganic magnetoelectric multiferroics. In the present short review, spinel and delafossite chromites are described. For the former, an electric polarization is evidenced in the ferrimagnetic state for ACr2O4 polycrystalline samples (A=Ni, Fe, Co). The presence of a JahnTeller cation such as Ni2+ at the A site is shown to yield larger polarization values. In the delafossites, substitution by V3+ at the Cr or Fe site in CuCrO2 (CuFeO2) suppresses the complex antiferromagnetic structure at the benefit of a spin glass state. The presence of cation disorder, probed by transmission electron microscopy, favors relaxor-like ferroelectricity. The results on the ferroelectricity of ferrimagnets and insulating spin glasses demonstrate that, in this research field, transition-metal oxides are worth to be studied. |
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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 |
London |
Editor |
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| |
Language |
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Wos |
000309783600006 |
Publication Date |
2012-02-09 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.299 |
Times cited |
27 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.299; 2012 IF: 2.040 |
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| |
Call Number |
UA @ lucian @ c:irua:101219 |
Serial |
1286 |
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| Permanent link to this record |
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| |
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Author |
Yan, Y.; Wang, L.-X.; Ke, X.; Van Tendeloo, G.; Wu, X.-S.; Yu, D.-P.; Liao, Z.-M. |
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| |
Title |
High-mobility Bi2Se3 nanoplates manifesting quantum oscillations of surface states in the sidewalls |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
|
| |
Volume |
4 |
Issue |
|
Pages |
3817-7 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Magnetotransport measurements of topological insulators are very important to reveal the exotic topological surface states for spintronic applications. However, the novel properties related to the surface Dirac fermions are usually accompanied by a large linear magnetoresistance under perpendicular magnetic field, which makes the identification of the surface states obscure. Here, we report prominent Shubnikov-de Haas (SdH) oscillations under an in-plane magnetic field, which are identified to originate from the surface states in the sidewalls of topological insulator Bi2Se3 nanoplates. Importantly, the SdH oscillations appear with a dramatically weakened magnetoresistance background, offering an easy path to probe the surface states directly when the coexistence of surface states and bulk conduction is inevitable. Moreover, under a perpendicular magnetic field, the oscillations in Hall conductivity have peak-to-valley amplitudes of 2 e(2)/h, giving confidence to achieve a quantum Hall effect in this system. A cross-section view of the nanoplate shows that the sidewall is (015) facet dominant and therefore forms a 586 angle with regard to the top/ bottom surface instead of being perpendicular; this gives credit to the surface states' behavior as two-dimensional transport. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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| |
Language |
|
Wos |
000330044700008 |
Publication Date |
2014-01-22 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2045-2322; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.259 |
Times cited |
31 |
Open Access |
|
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| |
Notes |
ERC grant Nu246791 – COUNTATOMS |
Approved |
Most recent IF: 4.259; 2014 IF: 5.578 |
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| |
Call Number |
UA @ lucian @ c:irua:114815 |
Serial |
1436 |
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| Permanent link to this record |
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Author |
Peng, X.; Peng, H.; Zhao, K.; Zhang, Y.; Xia, F.; Lyu, J.; Van Tendeloo, G.; Sun, C.; Wu, J. |
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Title |
Direct visualization of atomic-scale heterogeneous structure dynamics in MnO₂ nanowires |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
|
| |
Volume |
13 |
Issue |
28 |
Pages |
33644-33651 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Manganese oxides are attracting great interest owing to their rich polymorphism and multiple valent states, which give rise to a wide range of applications in catalysis, capacitors, ion batteries, and so forth. Most of their functionalities are connected to transitions among the various polymorphisms and Mn valences. However, their atomic-scale dynamics is still a great challenge. Herein, we discovered a strong heterogeneity in the crystalline structure and defects, as well as in the Mn valence state. The transitions are studied by in situ transmission electron microscopy (TEM), and they involve a complex ordering of [MnO6] octahedra as the basic building tunnels. MnO2 nanowires synthesized using solution-based hydrothermal methods usually exhibit a large number of multiple polymorphism impurities with different tunnel sizes. Upon heating, MnO2 nanowires undergo a series of stoichiometric polymorphism changes, followed by oxygen release toward an oxygen-deficient spinel and rock-salt phase. The impurity polymorphism exhibits an abnormally high stability with interesting small-large-small tunnel size transition, which is attributed to a preferential stabilizer (K+) concentration, as well as a strong competition of kinetics and thermodynamics. Our results unveil the complicated intergrowth of polymorphism impurities in MnO2, which provide insights into the heterogeneous kinetics, thermodynamics, and transport properties of the tunnel-based building blocks. |
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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 |
000677540900101 |
Publication Date |
2021-07-08 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
7.504 |
Times cited |
|
Open Access |
Not_Open_Access |
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| |
Notes |
|
Approved |
Most recent IF: 7.504 |
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| |
Call Number |
UA @ admin @ c:irua:180450 |
Serial |
6861 |
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| Permanent link to this record |
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Author |
Skorikov, A.; Batenburg, K.J.; Bals, S. |
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| |
Title |
Analysis of 3D elemental distribution in nanomaterials : towards higher throughput and dose efficiency |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
Journal of microscopy |
Abbreviated Journal |
|
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| |
Volume |
289 |
Issue |
3 |
Pages |
157-163 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Many advanced nanomaterials rely on carefully designed morphology and elemental distribution to achieve their functionalities. Among the few experimental techniques that can directly visualise the 3D elemental distribution on the nanoscale are approaches based on electron tomography in combination with energy-dispersive X-ray spectroscopy (EDXS) and electron energy loss spectroscopy (EELS). Unfortunately, these highly informative methods are severely limited by the fundamentally low signal-to-noise ratio, which makes long experimental times and high electron irradiation doses necessary to obtain reliable 3D reconstructions. Addressing these limitations has been the major research question for the development of these techniques in recent years. This short review outlines the latest progress on the methods to reduce experimental time and electron irradiation dose requirements for 3D elemental distribution analysis and gives an outlook on the development of this field in the near future. |
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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 |
000910532600001 |
Publication Date |
2022-12-26 |
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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 |
0022-2720 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2 |
Times cited |
2 |
Open Access |
OpenAccess |
|
| |
Notes |
ERC Consolidator Grant, Grant/Award Number: 815128 |
Approved |
Most recent IF: 2; 2023 IF: 1.692 |
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| |
Call Number |
UA @ admin @ c:irua:193428 |
Serial |
7281 |
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| Permanent link to this record |
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Author |
Schalm, O.; Crabbé, A.; Storme, P.; Wiesinger, R.; Gambirasi, A.; Grieten, E.; Tack, P.; Bauters, S.; Kleber, C.; Favaro, M.; Schryvers, D.; Vincze, L.; Terryn, H.; Patelli, A. |
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| |
Title |
The corrosion process of sterling silver exposed to a Na2S solution: monitoring and characterizing the complex surface evolution using a multi-analytical approach |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Applied Physics A-Materials Science & Processing |
Abbreviated Journal |
Appl Phys A-Mater |
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| |
Volume |
122 |
Issue |
122 |
Pages |
903 |
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| |
Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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| |
Abstract |
Many historical ‘silver’ objects are composed of sterling silver, a silver alloy containing small amounts of copper. Besides the dramatic impact of copper on the corrosion process, the chemical composition of the corrosion layer evolves continuously. The evolution of the surface during the exposure to a Na2S solution was monitored by means of visual observation at macroscopic level, chemical analysis at microscopic level and analysis at the nanoscopic level. The corrosion process starts with the preferential oxidation of copper, forming mixtures of oxides and sulphides while voids are being created beneath the corrosion layer. Only at a later stage, the silver below the corrosion layer is consumed. This results in the formation of jalpaite and at a later stage of acanthite. The acanthite is found inside the corrosion layer at the boundaries of jalpaite grains and as individual grains between the jalpaite grains but also as a thin film on top of the corrosion layer. The corrosion process could be described as a sequence of 5 subsequent surface states with transitions between these states. |
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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 |
000384753800033 |
Publication Date |
2016-09-20 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0947-8396 |
ISBN |
|
Additional Links |
|
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| |
Impact Factor |
1.455 |
Times cited |
9 |
Open Access |
|
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| |
Notes |
The authors are grateful for the financial support by the EU-FP7 Grant PANNA No. 282998 and for the opportunity to perform SR-XPS measurements at the NanoESCA beamline of the Elettra storage ring, under the approval of the advisory Committee (Proposal No. 20135164), as well as the opportunity to perform XANES measurements at the DUBBLE beamline of the ESRF storage ring (Proposal No. 26-01-990). The authors are grateful for the financial support by the STIMPRO Project FFB150215 of the University of Antwerp. Pieter Tack is funded by a Ph.D. Grant of the Agency for Innovation by Science and Technology (IWT). We would also like to thank Peter Van den Haute for the XRD measurements that were performed at the University of Ghent. |
Approved |
Most recent IF: 1.455 |
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| |
Call Number |
EMAT @ emat @ |
Serial |
4331 |
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| Permanent link to this record |
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Author |
Jones, L.; Yang, H.; Pennycook, T.J.; Marshall, M.S.J.; Van Aert, S.; Browning, N.D.; Castell, M.R.; Nellist, P.D. |
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| |
Title |
Smart Align : a new tool for robust non-rigid registration of scanning microscope data |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Advanced Structural and Chemical Imaging |
Abbreviated Journal |
|
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| |
Volume |
1 |
Issue |
1 |
Pages |
8 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Many microscopic investigations of materials may benefit from the recording of multiple successive images. This can include techniques common to several types of microscopy such as frame averaging to improve signal-to-noise ratios (SNR) or time series to study dynamic processes or more specific applications. In the scanning transmission electron microscope, this might include focal series for optical sectioning or aberration measurement, beam damage studies or camera-length series to study the effects of strain; whilst in the scanning tunnelling microscope, this might include bias-voltage series to probe local electronic structure. Whatever the application, such investigations must begin with the careful alignment of these data stacks, an operation that is not always trivial. In addition, the presence of low-frequency scanning distortions can introduce intra-image shifts to the data. Here, we describe an improved automated method of performing non-rigid registration customised for the challenges unique to scanned microscope data specifically addressing the issues of low-SNR data, images containing a large proportion of crystalline material and/or local features of interest such as dislocations or edges. Careful attention has been paid to artefact testing of the non-rigid registration method used, and the importance of this registration for the quantitative interpretation of feature intensities and positions is evaluated. |
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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 |
000218507000008 |
Publication Date |
2015-07-09 |
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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 |
2198-0926; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
131 |
Open Access |
|
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| |
Notes |
312483 Esteem2; esteem2_jra2 |
Approved |
Most recent IF: NA |
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| |
Call Number |
c:irua:126944 c:irua:126944 |
Serial |
3043 |
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| Permanent link to this record |
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Author |
Bourgeois, L.; Zhang, Y.; Zhang, Z.; Chen, Y.; Medhekar, N., V |
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Title |
Transforming solid-state precipitates via excess vacancies |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat Commun |
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| |
Volume |
11 |
Issue |
1 |
Pages |
1248 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Many phase transformations associated with solid-state precipitation look structurally simple, yet, inexplicably, take place with great difficulty. A classic case of difficult phase transformations is the nucleation of strengthening precipitates in high-strength lightweight aluminium alloys. Here, using a combination of atomic-scale imaging, simulations and classical nucleation theory calculations, we investigate the nucleation of the strengthening phase theta' onto a template structure in the aluminium-copper alloy system. We show that this transformation can be promoted in samples exhibiting at least one nanoscale dimension, with extremely high nucleation rates for the strengthening phase as well as for an unexpected phase. This template-directed solid-state nucleation pathway is enabled by the large influx of surface vacancies that results from heating a nanoscale solid. Template-directed nucleation is replicated in a bulk alloy as well as under electron irradiation, implying that this difficult transformation can be facilitated under the general condition of sustained excess vacancy concentrations. |
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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 |
000549162600025 |
Publication Date |
2020-03-06 |
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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 |
16.6 |
Times cited |
5 |
Open Access |
OpenAccess |
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| |
Notes |
; The authors are indebted to Matthew Weyland for his expert advice on aberrationcorrected scanning transmission electron microscopy. L.B. would like to acknowledge initial discussions with B.C. Muddle and J.F. Nie many years ago regarding the possible thermodynamic role of vacancies in solid-state precipitation. The authors acknowledge funding from the Australian Research Council (LE0454166, LE110100223), the Victorian State Government and Monash University for instrumentation, and use of the facilities within the Monash Centre for Electron Microscopy. The authors thank Flame Burgmann, Dougal McCulloch and Edwin Mayes for access to and assistance at the Microscopy and Microanalysis Facility at RMIT University. L.B. and N.M. acknowledge the financial support of the Australian Research Council (DP150100558). Authors also gratefully acknowledge the computational support from MonARCH, MASSIVE and the National Computing Infrastructure and Pawsey Supercomputing Centre. ZZ and YZ are thankful to Monash University for a Monash Graduate Scholarship, a Monash International Postgraduate Research Scholarship. Z.Z. is grateful for a Monash Centre for Electron Microscopy Postgraduate Scholarship. The authors are grateful to Anita Hill for advice. ; |
Approved |
Most recent IF: 16.6; 2020 IF: 12.124 |
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| |
Call Number |
UA @ admin @ c:irua:170797 |
Serial |
6635 |
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| Permanent link to this record |
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Author |
Hens, S.; Bender, H.; Donaton, R.A.; Maex, K.; Vanhaelemeersch, S.; van Landuyt, J. |
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| |
Title |
EFTEM study of plasma etched low-k Si-O-C dielectrics |
Type |
A1 Journal article |
| |
Year |
2001 |
Publication |
Institute of physics conference series
T2 – Royal-Microscopical-Society Conference on Microscopy of Semiconducting, Materials, MAR 25-29, 2001, UNIV OXFORD, OXFORD, ENGLAND |
Abbreviated Journal |
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| |
Volume |
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Issue |
169 |
Pages |
415-418 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Materials with low dielectric constant ("low-k'') in combination with Cu metallization are replacing the oxide based dielectrics with Al metallization in future generations of micro-electronic devices. In this work, a carbon doped oxide low-k dielectric material is studied after different kinds of etch/strip steps in single damascene Cu. filled line structures. Interline capacitance measurements indicate a dependence of the dielectric constant on the strip conditions. EFTEM is used to study the composition of the dielectric material and the modification of the low-k material at the sidewall of the etched structures for the various treatment 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 |
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Publication Date |
0000-00-00 |
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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 |
0-7503-0818-4; 0951-3248 |
ISBN |
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Additional Links |
UA library record; WoS full record; |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:103432 |
Serial |
877 |
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| Permanent link to this record |
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Author |
Quintanilla, M.; Zhang, Y.; Liz-Marzan, L.M. |
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| |
Title |
Subtissue plasmonic heating monitored with CaF2:Nd3+,Y3+ nanothermometers in the second biological window |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
30 |
Issue |
8 |
Pages |
2819-2828 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Measuring temperature in biological environments is an ambitious goal toward supporting medical treatment and diagnosis. Minimally invasive techniques based on optical probes require very specific properties that are difficult to combine within a single material. These include high chemical stability in aqueous environments, optical signal stability, low toxicity, high emission intensity, and, essential, working at wavelengths within the biological transparency windows so as to minimize invasiveness while maximizing penetration depth. We propose CaF2:Nd3+,Y3+ as a candidate for thermometry based on an intraband ratiometric approach, fully working within the biological windows (excitation at 808 nm; emission around 1050 nm). We optimized the thermal probes through the addition of Y3+ as a dopant to improve both emission intensity and thermal sensitivity. To define the conditions under which the proposed technique can be applied, gold nanorods were used to optically generate subtissue hot areas, while the resulting temperature variation was monitored with the new nanothermometers. |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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Language |
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Wos |
000431088400038 |
Publication Date |
2018-03-27 |
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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 |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
28 |
Open Access |
Not_Open_Access |
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Notes |
; The authors would like to thank Dr. Guillermo Gonzalez Rubio for the kind support with the synthesis of gold nanorods. M.Q and L.M.L.-M. acknowledge financial support from the European Commission under the Marie Sklodowska-Curie program (H2020-MSCA-IF-2014_659021 – PHELLINI). Y.Z. acknowledges financial support from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 665501 through a FWO [PEGASUS]^2 Marie Sklodowska-Curie fellowship (12U4917N). ; |
Approved |
Most recent IF: 9.466 |
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Call Number |
UA @ lucian @ c:irua:151576 |
Serial |
5042 |
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| Permanent link to this record |
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Author |
Zaghi, A.E.; Buffière, M.; Brammertz, G.; Batuk, M.; Lenaers, N.; Kniknie, B.; Hadermann, J.; Meuris, M.; Poortmans, J.; Vleugels, J. |
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Title |
Mechanical synthesis of high purity Cu-In-Se alloy nanopowder as precursor for printed CISe thin film solar cells |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Advanced powder technology |
Abbreviated Journal |
Adv Powder Technol |
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Volume |
25 |
Issue |
4 |
Pages |
1254-1261 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Mechanical alloying and ball milling are low cost, up-scalable techniques for the preparation of high purity chalcogenide nanopowders to be used as precursor material for printing thin film solar cells. In this study, high purity copper indium selenium (Cu-In-Se) alloy nanopowders with 20-200 nm particle size were synthesized from macroscopic elemental Cu, In and Se powders via mechanical alloying and planetary ball milling. The particle size distribution, morphology, composition, and purity level of the synthesized Cu-In-Se alloy nanopowders were investigated. Thin Cu-In-Se alloy nanopowder ink coatings, deposited on Mo-coated glass substrates by doctor blading, were converted into a CuInSe2 semiconductor film by selenization heat treatment in Se vapor. The CuInSe2 film showed semiconducting band gap around 1 eV measured by photoluminescence spectroscopy. CuInSe2 absorber layer based thin film solar cell devices were fabricated to assess their performance. The solar cell device showed a total efficiency of 4.8%, as measured on 0.25 cm(2) area cell. (c) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved. |
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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 |
Zeist |
Editor |
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Language |
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Wos |
000341871700015 |
Publication Date |
2014-03-17 |
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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 |
0921-8831; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.659 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.659; 2014 IF: 2.638 |
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Call Number |
UA @ lucian @ c:irua:119896 |
Serial |
1977 |
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| Permanent link to this record |
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Author |
Guo, A.; Bai, H.; Liang, Q.; Feng, L.; Su, X.; Van Tendeloo, G.; Wu, J. |
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Title |
Resistive switching in Ag₂Te semiconductor modulated by Ag+-ion diffusion and phase transition |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Advanced Electronic Materials |
Abbreviated Journal |
Adv Electron Mater |
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Volume |
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Issue |
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Pages |
2200850-2200858 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Memristors are considered to be the fourth circuit element and have great potential in areas like logic operations, information storage, and neuromorphic computing. The functional material in a memristor, which has a nonlinear resistance, is the key component to be developed. Herein, resistive switching is demonstrated and the structural evolutions in Ag2Te are examined under an external electric field. It is shown that the electroresistance effect is originating from an electronically triggered phase transition together with directional Ag+-ion diffusion. Using in situ transmission electron microscopy, the phase transition from the monoclinic alpha-Ag2Te into the face-centered cubic beta-Ag2Te, accompanied by a change in resistance, is directly observed. Diffusion of Ag+-ions modulates the localized density of Ag+-ion vacancies, leading to a change in electrical conductivity and influences the threshold voltage to trigger the phase transition. During the electric field-driven phase transition, the spontaneous and localized multiple polarizations from the low-symmetry alpha-Ag2Te (referring to an antiferroelectric structure) are vanishing in the cubic beta-Ag2Te (referring to a paraelectric structure). The abrupt resistance change of thin Ag2Te caused by the phase transition and modulated by the applied electric field demonstrates its great potential as functional material in volatile memory and memristors with a low-energy consumption. |
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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 |
000855728500001 |
Publication Date |
2022-09-21 |
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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 |
2199-160x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.2 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 6.2 |
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Call Number |
UA @ admin @ c:irua:190582 |
Serial |
7203 |
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| Permanent link to this record |
