| |
Records |
Links |
|
Author |
Perez, A.J.; Batuk, D.; Saubanère, M.; Rousse, G.; Foix, D.; Mc Calla, E.; J. Berg, E.; Dugas, R.; van den Bos, K. H. W.; Doublet, M.-L.; Gonbeau, D.; Abakumov, A.M.; Van Tendeloo, G.; Tarascon, J.-M. |
|
| |
Title |
Strong oxygen participation in the redox governing the structural and electrochemical properties of Na-rich layered oxide Na2IrO3 |
Type |
A1 Journal article |
| |
Year  |
2016 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
| |
Volume |
28 |
Issue |
28 |
Pages |
8278-8288 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The recent revival of the Na-ion battery concept has prompted intense activities in the search for new Na-based layered oxide positive electrodes. The largest capacity to date was obtained for a Na-deficient layered oxide that relies on cationic redox processes only. To go beyond this limit, we decided to chemically manipulate these Na-based layered compounds in a way to trigger the participation of the anionic network. We herein report the electrochemical properties of a Na-rich phase Na2IrO3, which can reversibly cycle 1.5 Na+ per formula unit while not suffering from oxygen release nor cationic migrations. Such large capacities, as deduced by complementary XPS, X-ray/neutron diffraction and transmission electron microscopy measurements, arise from cumulative cationic and anionic redox processes occurring simultaneously at potentials as low as 3.0 V. The inability to remove more than 1.5 Na+ is rooted in the formation of an O1-type phase having highly stabilized Na sites as confirmed by DFT calculations, which could rationalize as well the competing metal/oxygen redox processes in Na2IrO3. This work will help to define the most fertile directions in the search for novel high energy Na-rich materials based on more sustainable elements than Ir. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000388914500021 |
Publication Date |
2016-10-17 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
9.466 |
Times cited |
45 |
Open Access |
|
|
| |
Notes |
The authors thank Montse Casas-Cabanas and Marine Reynaud for discussions about the FAULTS program, Sandra Van Aert for her great help in guiding us towards the use of the statistical parameter estimation method for establishing the O-O histogram, and Thomas Hansen and Vladimir Pomjakushin for their precious help in neutron diffraction experiments. This work is based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institute, Villigen, Switzerland, and at Institut Laue Langevin, Grenoble, France. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the U.S. department of Energy under contract No. DE-AC02-06CH11357 and is greatly acknowledged. |
Approved |
Most recent IF: 9.466 |
|
| |
Call Number |
EMAT @ emat @ c:irua:135994 |
Serial |
4287 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Walter, A.L.; Sahin, H.; Kang, J.; Jeon, K.J.; Bostwick, A.; Horzum, S.; Moreschini, L.; Chang, Y.J.; Peeters, F.M.; Horn, K.; Rotenberg, E.; |
|
| |
Title |
New family of graphene-based organic semiconductors : an investigation of photon-induced electronic structure manipulation in half-fluorinated graphene |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
93 |
Issue |
93 |
Pages |
075439 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The application of graphene to electronic and optoelectronic devices is limited by the absence of reliable semiconducting variants of this material. A promising candidate in this respect is graphene oxide, with a band gap on the order of similar to 5 eV, however, this has a finite density of states at the Fermi level. Here, we examine the electronic structure of three variants of half-fluorinated carbon on Sic(0001), i.e., the (6 root 3 x 6 root 3) R30 degrees C/SiC “buffer layer,” graphene on this (6 root 3 x 6 root 3) R30 degrees C/SiC buffer layer, and graphene decoupled from the SiC substrate by hydrogen intercalation. Using angle-resolved photoemission, core level photoemission, and x-ray absorption, we show that the electronic, chemical, and physical structure of all three variants is remarkably similar, exhibiting a large band gap and a vanishing density of states at the Fermi level. These results are explained in terms of first-principles calculations. This material thus appears very suitable for applications, even more so since it is prepared on a processing-friendly substrate. We also investigate two separate UV photon-induced modifications of the electronic structure that transform the insulating samples (6.2-eV band gap) into semiconducting (similar to 2.5-eV band gap) and metallic regions, respectively. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000371398000007 |
Publication Date |
2016-02-29 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
; The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under Contract No. DE-AC02-05CH11231. Work in Erlangen was supported by the DFG through SPP 1459 “Graphene” and SFB 953 “Synthetic Carbon Allotropes” and by the ESF through the EURO-Graphene project GraphicRF. A.L.W. acknowledges support from the Max-Planck-Gesellschaft, the Donostia International Physics Centre, and the Centro de Fisica de Materiales in San Sebastian, Spain, and Brookhaven National Laboratory under US Department of Energy, Office of Science, Office of Basic Energy Sciences, Contract No. DE-SC0012704. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. Y.J.C. acknowledges support from the National Research Foundation of Korea under Grant No. NRF-2014R1A1A1002868. The authors gratefully acknowledge the work of T. Seyller's group at the Institut fur Physik, Technische Universitat Chemnitz, Germany for providing the samples. ; |
Approved |
Most recent IF: 3.836 |
|
| |
Call Number |
UA @ lucian @ c:irua:132352 |
Serial |
4213 |
|
| Permanent link to this record |
| |
|
| |
|
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. |
|
| |
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 |
|
| |
Volume |
350 |
Issue |
350 |
Pages |
1516-1521 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
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. |
|
| |
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 |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Wos |
000366591100056 |
Publication Date |
2015-12-17 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0036-8075 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
37.205 |
Times cited |
281 |
Open Access |
|
|
| |
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 |
|
| |
Call Number |
c:irua:130202 |
Serial |
4005 |
|
| Permanent link to this record |
| |
|
| |
|
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.; |
|
| |
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 |
|
| |
Volume |
162 |
Issue |
162 |
Pages |
A1341-A1351 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
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. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
| |
Language |
|
Wos |
000355643700030 |
Publication Date |
2015-04-29 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0013-4651;1945-7111; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.259 |
Times cited |
23 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.259; 2015 IF: 3.266 |
|
| |
Call Number |
c:irua:126445 |
Serial |
2903 |
|
| Permanent link to this record |
| |
|
| |
|
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.; |
|
| |
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 |
|
| |
Volume |
137 |
Issue |
137 |
Pages |
4804-4814 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
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. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
| |
Language |
|
Wos |
000353177100036 |
Publication Date |
2015-03-26 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
13.858 |
Times cited |
86 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 13.858; 2015 IF: 12.113 |
|
| |
Call Number |
c:irua:126019 |
Serial |
3805 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Walter, A.L.; Sahin, H.; Jeon, K.J.; Bostwick, A.; Horzum, S.; Koch, R.; Speck, F.; Ostler, M.; Nagel, P.; Merz, M.; Schupler, S.; Moreschini, L.; Chang, Y.J.; Seyller, T.; Peeters, F.M.; Horn, K.; Rotenberg, E.; |
|
| |
Title |
Luminescence, patterned metallic regions, and photon-mediated electronic changes in single-sided fluorinated graphene sheets |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
| |
Volume |
8 |
Issue |
8 |
Pages |
7801-7808 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Single-sided fluorination has been predicted to open an electronic band gap in graphene and to exhibit unique electronic and magnetic properties; however, this has not been substantiated by experimental reports. Our comprehensive experimental and theoretical study of this material on a SiC(0001) substrate shows that single-sided fluorographene exhibits two phases, a stable one with a band gap of similar to 6 eV and a metastable one, induced by UV irradiation, with a band gap of similar to 2.5 eV. The metastable structure, which reverts to the stable “ground-state” phase upon annealing under emission of blue light, in our view is induced by defect states, based on the observation of a nondispersive electronic state at the top of the valence band, not unlike that found in organic molecular layers. Our structural data show that the stable C2F ground state has a “boat” structure, in agreement with our X-ray magnetic circular dichroism data, which show the absence of an ordered magnetic phase. A high flux of UV or X-ray photons removes the fluorine atoms, demonstrating the possibility of lithographically patterning conducting regions into an otherwise semiconducting 2D material. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000340992300025 |
Publication Date |
2014-08-09 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
13.942 |
Times cited |
23 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
| |
Call Number |
UA @ lucian @ c:irua:119263 |
Serial |
1857 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rosenberg, E.; De Santis, F.; Kontozova-Deutsch, V.; Odlyha, M.; Van Grieken, R.; Vichi, F. |
|
| |
Title |
Measuring gaseous and particulate pollutants: instruments and instrumental problems |
Type |
H2 Book chapter |
| |
Year |
2010 |
Publication |
|
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
115-146
T2 - Basic environmental mechanisms: affec |
|
| |
Keywords |
H2 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
|
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-88-404-4334-8 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:83559 |
Serial |
8213 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Lazoryak, B.I.; Morozov, V.A.; Belik, A.A.; Stefanovich, S.Y.; Grebenev, V.V.; Leonidov, I.A.; Mitberg, E.B.; Davydov, S.A.; Lebedev, O.I.; Van Tendeloo, G. |
|
| |
Title |
Ferroelectric phase transition in the whitlockite-type Ca9Fe(PO4)7; crystal structure of the paraelectric phase at 923 K |
Type |
A1 Journal article |
| |
Year |
2004 |
Publication |
Solid state sciences |
Abbreviated Journal |
Solid State Sci |
|
| |
Volume |
6 |
Issue |
2 |
Pages |
185-195 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
|
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
| |
Language |
|
Wos |
000220312700005 |
Publication Date |
2004-02-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1293-2558; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.811 |
Times cited |
41 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 1.811; 2004 IF: 1.598 |
|
| |
Call Number |
UA @ lucian @ c:irua:54699 |
Serial |
1180 |
|
| Permanent link to this record |
