Records |
Author |
Paolella, A.; Turner, S.; Bertoni, G.; Hovington, P.; Flacau, R.; Boyer, C.; Feng, Z.; Colombo, M.; Marras, S.; Prato, M.; Manna, L.; Guerfi, A.; Demopoulos, G.P.; Armand, M.; Zaghib, K.; |
Title |
Accelerated removal of Fe-antisite defects while nanosizing hydrothermal LiFePO4 with Ca2+ |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
Volume |
16 |
Issue |
16 |
Pages |
2692-2697 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Based on neutron powder diffraction (NPD) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), we show that calcium ions help eliminate the Fe-antisite defects by controlling the nucleation and evolution of the LiFePO4 particles during their hydrothermal synthesis. This Ca-regulated formation of LiFePO4 particles has an overwhelming impact on the removal of their iron antisite defects during the subsequent carbon coating step since (i) almost all the Fe-antisite defects aggregate at the surface of the LiFePO4 crystal when the crystals are small enough and (ii) the concomitant increase of the surface area, which further exposes the Fe-antisite defects. Our results not only justify a low-cost, efficient and reliable hydrothermal synthesis method for LiFePO4 but also provide a promising alternative viewpoint on the mechanism controlling the nanosizing of LiFePO4, which leads to improved electrochemical performances. |
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 |
Editor |
|
Language |
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Wos |
000374274600084 |
Publication Date |
2016-03-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.712 |
Times cited |
30 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.712 |
Call Number |
UA @ lucian @ c:irua:133600 |
Serial |
4134 |
Permanent link to this record |
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Author |
De Backer, A.; van den Bos, K.H.W.; Van den Broek, W.; Sijbers, J.; Van Aert, S. |
Title |
StatSTEM: An efficient approach for accurate and precise model-based quantification of atomic resolution electron microscopy images |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
171 |
Issue |
171 |
Pages |
104-116 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, has been investigated. The highest attainable precision is reached even for low dose images. Furthermore, the advantages of the model-based approach taking into account overlap between neighbouring columns are highlighted. This is done for the estimation of the distance between two neighbouring columns as a function of their distance and for the estimation of the scattering cross-section which is compared to the integrated intensity from a Voronoi cell. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. |
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 |
000389106200014 |
Publication Date |
2016-09-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
43 |
Open Access |
|
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0393.11, G.0064.10 and G.0374.13), a Ph.D. research grant to K.H.W. van den Bos, and a postdoctoral research grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). A. Rosenauer is acknowledged for providing the STEMsim program.; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
Call Number |
EMAT @ emat @ c:irua:135516 |
Serial |
4280 |
Permanent link to this record |
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Author |
Guidini, A.; Flammia, L.; Milošević, M.V.; Perali, A. |
Title |
BCS-BEC crossover in quantum confined superconductors |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
Volume |
29 |
Issue |
29 |
Pages |
711-715 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Ultranarrow superconductors are in the strong quantum confinement regime with formation of multiple coherent condensates associated with the many subbands of the electronic structure. Here, we analyze the multiband BCS-BEC crossover induced by the chemical potential tuned close to a subband bottom, in correspondence of a superconducting shape resonance. The evolution of the condensate fraction and of the pair correlation length in the ground state as functions of the chemical potential demonstrates the tunability of the BCS-BEC crossover for the condensate component of the selected subband. The extension of the crossover regime increases when the pairing strength and/or the characteristic energy of the interaction get larger. Our results indicate the coexistence of large and small Cooper pairs in the crossover regime, leading to the optimal parameter configuration for high transition temperature superconductivity. |
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 |
000371089500034 |
Publication Date |
2015-12-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1557-1939 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.18 |
Times cited |
12 |
Open Access |
|
Notes |
; We acknowledge A. Bianconi and A.A. Shanenko for useful discussions. A.P. acknowledges financial support from the University of Camerino under the project FAR “Control and enhancement of superconductivity by engineering materials at the nanoscale”. M.V.M. acknowledges support from the Research Foundation – Flanders (FWO) and the Special Research Funds of the University of Antwerp (BOF-UA). A.P. and M.V.M. acknowledge the collaboration within the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions. ; |
Approved |
Most recent IF: 1.18 |
Call Number |
UA @ lucian @ c:irua:132287 |
Serial |
4143 |
Permanent link to this record |
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Author |
Bacaksiz, C.; Cahangirov, S.; Rubio, A.; Senger, R.T.; Peeters, F.M.; Sahin, H. |
Title |
Bilayer SnS2 : tunable stacking sequence by charging and loading pressure |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
125403 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Employing density functional theory-based methods, we investigate monolayer and bilayer structures of hexagonal SnS2, which is a recently synthesized monolayer metal dichalcogenide. Comparison of the 1H and 1T phases of monolayer SnS2 confirms the ground state to be the 1T phase. In its bilayer structure we examine different stacking configurations of the two layers. It is found that the interlayer coupling in bilayer SnS2 is weaker than that of typical transition-metal dichalcogenides so that alternative stacking orders have similar structural parameters and they are separated with low energy barriers. A possible signature of the stacking order in the SnS2 bilayer has been sought in the calculated absorbance and reflectivity spectra. We also study the effects of the external electric field, charging, and loading pressure on the characteristic properties of bilayer SnS2. It is found that (i) the electric field increases the coupling between the layers at its preferred stacking order, so the barrier height increases, (ii) the bang gap value can be tuned by the external E field and under sufficient E field, the bilayer SnS2 can become a semimetal, (iii) the most favorable stacking order can be switched by charging, and (iv) a loading pressure exceeding 3 GPa changes the stacking order. The E-field tunable band gap and easily tunable stacking sequence of SnS2 layers make this 2D crystal structure a good candidate for field effect transistor and nanoscale lubricant applications. |
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 |
|
Wos |
000371405000005 |
Publication Date |
2016-03-03 |
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 |
38 |
Open Access |
|
Notes |
; The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). C.B., H.S., and R.T.S. acknowledge support from TUBITAK Project No. 114F397. H.S. is supported by an FWO Pegasus Marie Curie Fellowship. S.C. and A.R. acknowledge financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, the European Research Council (ERC-2010-AdG-267374), and Spanish grant Grupos Consolidados (IT578-13). S.C. acknowledges support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:132345 |
Serial |
4144 |
Permanent link to this record |
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Author |
Chinchilla, L.E.; Olmos, C.; Kurttepeli, M.; Bals, S.; Van Tendeloo, G.; Villa, A.; Prati, L.; Blanco, G.; Calvino, J.J.; Chen, X.; Hungría, A.B. |
Title |
Combined macroscopic, nanoscopic, and atomic-scale characterization of gold-ruthenium bimetallic catalysts for octanol oxidation |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Particle and particle systems characterization |
Abbreviated Journal |
Part Part Syst Char |
Volume |
33 |
Issue |
33 |
Pages |
419-437 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
A series of gold-ruthenium bimetallic catalysts of increasing Au:Ru molar ratios supported on a Ce0.62Zr0.38O2 mixed oxide are prepared and their structural and chemical features characterized by a combination of macroscopic and atomic-scale techniques based on scanning transmission electron microscopy. The influence of the temperature of the final reduction treatment used as activation step (350-700 degrees C range) is also investigated. The preparation method used allows catalysts to be successfully prepared where a major fraction of the metal nanoparticles is in the size range below 5 nm. The structural complexities characteristic of this type of catalysts are evidenced, as well as the capabilities and limitations of both the macroscopic and microscopic techniques in the characterization of the system of metal nanoparticles. A positive influence of the addition of Ru on both the resistance against sintering and the catalytic performance of the starting supported Au catalyst is evidenced. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000379970000011 |
Publication Date |
2016-05-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0934-0866 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.474 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
; This work was supported by the Ministry of Science and Innovation of Spain/ FEDER Program of the EU (Project Nos.: MAT 2013-40823-R and CSD2009-00013), ESTEEM2 (FP7-INFRASTUCTURE-2012-1-312493), Junta de Andalucia (FQM334 and FQM110 and Project: FQM3994). S.B. acknowledges the European Research Council, ERC grant No. 335078 – Colouratom. M.K. is grateful to the Fund for Scientific Research Flanders. X.C. thanks the Ramon y Cajal Program. ; ecas_sara |
Approved |
Most recent IF: 4.474 |
Call Number |
UA @ lucian @ c:irua:134958 |
Serial |
4150 |
Permanent link to this record |
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Author |
Agarwal, T.; Sorée, B.; Radu, I.; Raghavan, P.; Fiori, G.; Iannaccone, G.; Thean, A.; Heyns, M.; Dehaene, W. |
Title |
Comparison of short-channel effects in monolayer MoS2 based junctionless and inversion-mode field-effect transistors |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
108 |
Issue |
108 |
Pages |
023506 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Conventional junctionless (JL) multi/gate (MuG) field-effect transistors (FETs) require extremely scaled channels to deliver high on-state current with low short-channel effect related leakage. In this letter, using ultra-thin 2D materials (e.g., monolayer MoS2), we present comparison of short-channel effects in JL, and inversion-mode (IM) FETs. We show that JL FETs exhibit better sub-threshold slope (S.S.) and drain-induced-barrier-lowering (DIBL) in comparison to IM FETs due to reduced peak electric field at the junctions. But, threshold voltage (VT) roll-off with channel length downscaling is found to be significantly higher in JL FETs than IM FETs, due to higher source/drain controlled charges (dE/dx) in the channel. Further, we show that although VT roll-off in JL FETs improves by increasing the gate control, i.e., by scaling the oxide, or channel thickness, the sensitivity of threshold voltage on structural parameters is found out to be high. (C) 2016 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000370258400056 |
Publication Date |
2016-01-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
13 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.411 |
Call Number |
UA @ lucian @ c:irua:132318 |
Serial |
4152 |
Permanent link to this record |
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Author |
Sahin, H.; Torun, E.; Bacaksiz, C.; Horzum, S.; Kang, J.; Senger, R.T.; Peeters, F.M. |
Title |
Computing optical properties of ultra-thin crystals |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Wiley Interdisciplinary Reviews: Computational Molecular Science |
Abbreviated Journal |
Wires Comput Mol Sci |
Volume |
6 |
Issue |
6 |
Pages |
351-368 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
An overview is given of recent advances in experimental and theoretical understanding of optical properties of ultra-thin crystal structures (graphene, phosphorene, silicene, MoS2 , MoSe2, WS2, WSe2, h-AlN, h-BN, fluorographene, and graphane). Ultra-thin crystals are atomically thick-layered crystals that have unique properties which differ from their 3D counterpart. Because of the difficulties in the synthesis of few-atom-thick crystal structures, which are thought to be the main building blocks of future nanotechnology, reliable theoretical predictions of their electronic, vibrational, and optical properties are of great importance. Recent studies revealed the reliable predictive power of existing theoretical approaches based on density functional theory. (C) 2016 John Wiley & Sons, Ltd WIREs Comput Mol Sci 2016, 6:351-368. doi: 10.1002/wcms.1252 For further resources related to this article, please visit the . |
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 |
000379267300002 |
Publication Date |
2016-02-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1759-0876 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
14.016 |
Times cited |
14 |
Open Access |
|
Notes |
; 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). H.S. is supported by a FWO Pegasus Long Marie Curie Fellowship. J.K. is supported by a FWO Pegasus short Marie Curie Fellowship. ; |
Approved |
Most recent IF: 14.016 |
Call Number |
UA @ lucian @ c:irua:134649 |
Serial |
4155 |
Permanent link to this record |
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Author |
Dharanipragada, N.V.R.A.; Meledina, M.; Galvita, V.V.; Poelman, H.; Turner, S.; Van Tendeloo, G.; Detavernier, C.; Marin, G.B. |
Title |
Deactivation study of Fe2O3-CeO2 during redox cycles for CO production from CO2 |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Industrial and engineering chemistry research |
Abbreviated Journal |
Ind Eng Chem Res |
Volume |
55 |
Issue |
55 |
Pages |
5911-5922 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Deactivation was investigated in Fe2O3-CeO2 oxygen storage materials during repeated H-2-reduction and CO2-reoxidation. In situ XRD, XAS, and TEM were used to identify phases, crystallite sizes, and morphological changes upon cycling operation. The effect of redox cycling was investigated both in Fe-rich (80 wt % Fe2O3-CeO2) and Ce-rich (10 wt %Fe2O3-CeO2) materials. The former consisted of 100 nm Fe2O3 particles decorated with 5-10 nm Ce1-xFexO2-x. The latter presented CeO2 with incorporated Fe, i.e. a solid solution of Ce1-xFexO2-x, as the main oxygen carrier. By modeling the EXAFS Ce-K signal for as-prepared 10 wt %Fe2O3-CeO2, the amount of Fe in CeO2 was determined as 21 mol %, corresponding to 86% of the total iron content. Sintering and solid solid transformations, the latter including both new phase formation and element segregation, were identified as deactivation pathways upon redox cycling. In Ce-rich material, perovskite (CeFeO3) was identified by XRD. This phase remained inert during reduction and reoxidation, resulting in an overall lower oxygen storage capacity. Further, Fe segregated from the solid solution, thereby decreasing its reducibility. In addition, an increase in crystallite size occurred for all phases. In Fe-rich material, sintering is the main deactivation pathway, although Fe segregation from the solid solution and perovskite formation cannot be excluded. |
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. |
Editor |
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Language |
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Wos |
000376825300013 |
Publication Date |
2016-04-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0888-5885; 1520-5045 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
26 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.843 |
Call Number |
UA @ lucian @ c:irua:134214 |
Serial |
4158 |
Permanent link to this record |
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Author |
Yang, S.; Kang, J.; Yue, Q.; Coey, J.M.D.; Jiang, C. |
Title |
Defect-modulated transistors and gas-enhanced photodetectors on ReS2 nanosheets |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
Volume |
3 |
Issue |
3 |
Pages |
1500707 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
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 |
000373149400011 |
Publication Date |
2016-01-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2196-7350; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.279 |
Times cited |
22 |
Open Access |
|
Notes |
; This work was supported by the National Natural Science Foundations of China (NSFC) under Grant No.51331001. The authors thank S. Tongay for giving them the ReS<INF>2</INF> crystals. ; |
Approved |
Most recent IF: 4.279 |
Call Number |
UA @ lucian @ c:irua:133232 |
Serial |
4159 |
Permanent link to this record |
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Author |
Lemoine, G.; Delannay, L.; Idrissi, H.; Colla, M.-S.; Pardoen, T. |
Title |
Dislocation and back stress dominated viscoplasticity in freestanding sub-micron Pd films |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
Volume |
111 |
Issue |
111 |
Pages |
10-21 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
A dislocation-based crystal plasticity model is developed in order to study the mechanical and creep/ relaxation behaviour of polycrystalline metallic thin films. The model accounts for the confinement of plasticity due to grain boundaries and for the anisotropy of individual grains, as well as for the significant viscoplastic effects associated to dislocation dominated thermally activated mechanisms. Numerical predictions are assessed based on experimental tensile test followed by relaxation on freestanding Pd films, based on an on-chip test technique. The dislocation-based mechanism assumption captures all the experimental trends, including the stress strain response, the relaxation behaviour and the dislocation density evolution, confirming the dominance of a dislocation driven deformation mechanism for the present Pd films with high defects density. The model has also been used to address some original experimental evidences involving back stresses, Bauschinger effect, backward creep and strain recovery. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000375812100002 |
Publication Date |
2016-03-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1359-6454 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.301 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 5.301 |
Call Number |
UA @ lucian @ c:irua:133636 |
Serial |
4162 |
Permanent link to this record |
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Author |
Berdiyorov, G.R.; Madjet, M.E.; El-Mellouhi, F.; Peeters, F.M. |
Title |
Effect of crystal structure on the electronic transport properties of the organometallic perovskite CH3NH3PbI3 |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Solar energy materials and solar cells
T2 – 2nd International Renewable and Sustainable Energy Conference (IRSEC), OCT 17-19, 2014, Ouarzazate, MOROCCO |
Abbreviated Journal |
Sol Energ Mat Sol C |
Volume |
148 |
Issue |
148 |
Pages |
60-66 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Using density-functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of the crystal lattice structure of organometallic perovskite CH3NH3PbI3 on its electronic transport properties. Both dispersive interactions and spin-orbit coupling are taken into account in describing structural and electronic properties of the system. We consider two different phases of the material, namely the orthorhombic and cubic lattice structures, which are energetically stable at low (< 160 K) and high (> 330 K) temperatures, respectively. The sizable geometrical differences between the two structures in term of lattice parameters, PbI6 octahedral tilts, rotation and deformations, have considerable impact on the transport properties of the material. For example, at zero bias and for all considered electron energies, the cubic phase has a larger transmission than the orthorhombic one, although both show similar electronic densities of states. Depending on the applied voltage, the current in the cubic system can be several orders of magnitude larger as compared to the one obtained for the orthorhombic sample. We attribute this enhancement in the transmission to the presence of extended states in the cubic phase due to the symmetrically shaped and ordered PbI6 octaherdra. (C) 2015 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Elsevier science bv |
Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000371944500011 |
Publication Date |
2015-11-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-0248 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.784 |
Times cited |
16 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 4.784 |
Call Number |
UA @ lucian @ c:irua:133151 |
Serial |
4163 |
Permanent link to this record |
|
|
|
Author |
Roy, P.; Torun, E.; de Groot, R.A. |
Title |
Effect of doping and elastic properties in (Mn,Fe)2(Si,P) |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
094110 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Mixed magnetism (the coexistence of strong and weak magnetism in one material) is regarded as the origin of the giant magnetocaloric effect (GMCE). A good example is (Mn,Fe)(2)(Si,P), which is established as one of the best magnetocaloric materials available. Tuning the material properties are essential for optimizing its performance, and a straightforward way to do that is by doping. In this article, an ab initio electronic structure method was used to calculate the structure and magnetic properties of 3d-transition-metal-doped (Mn,Fe)(2)(Si,P) materials for magnetocaloric applications (transition metals are Cr, Co, Mn, Ni, Cu). For a steady performance, the material should be mechanically stable. A detailed analysis of the elastic constants shows that the mechanical stability of the (Mn,Fe)(2)(Si,P) system increases significantly by doping with boron without affecting the magnetic properties. Insights of the influence of doping enable future studies to understand and predict bettermagnetocaloric materials. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000372712100001 |
Publication Date |
2016-03-25 |
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 |
9 |
Open Access |
|
Notes |
; This work is part of an Industrial Partnership Programme (IPP I28) of Fundamenteel Onderzoek der Materie (FOM) (The Netherlands) and co-financed by BASF New Business. The authors would like to thank Phuong Thao Nguyen and Dr. Gilles A. de Wijs for very useful discussions. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:133192 |
Serial |
4164 |
Permanent link to this record |
|
|
|
Author |
Berdiyorov, G.R.; El-Mellouhi, F.; Madjet, M.E.; Alharbi, F.H.; Peeters, F.M.; Kais, S. |
Title |
Effect of halide-mixing on the electronic transport properties of organometallic perovskites |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Solar energy materials and solar cells
T2 – 2nd International Renewable and Sustainable Energy Conference (IRSEC), OCT 17-19, 2014, Ouarzazate, MOROCCO |
Abbreviated Journal |
Sol Energ Mat Sol C |
Volume |
148 |
Issue |
148 |
Pages |
2-10 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Using density-functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of iodide/chloride and iodide/bromide mixing on the electronic transport in lead based organometallic perovskite CH3NH3PbI3, which is known to be an effective tool to tune the electronic and optical properties of such materials. We found that depending on the level and position of the halide mixing, the electronic transport can be increased by more than a factor of 4 for a given voltage biasing. The largest current is observed for small concentration of bromide substitutions located at the equatorial sites. However, full halide substitution has a negative effect on the transport properties of this material: the current drops by an order of magnitude for both CH3NH3PbCl3 and CH3NH3PbBr3 samples. (C) 2015 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier science bv |
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000371944500002 |
Publication Date |
2015-12-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-0248 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.784 |
Times cited |
23 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 4.784 |
Call Number |
UA @ lucian @ c:irua:133150 |
Serial |
4165 |
Permanent link to this record |
|
|
|
Author |
Bakalov, P.; Esfahani, D.N.; Covaci, L.; Peeters, F.M.; Tempere, J.; Locquet, J.-P. |
Title |
Electric-field-driven Mott metal-insulator transition in correlated thin films : an inhomogeneous dynamical mean-field theory approach |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
165112 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
Abstract |
Simulations are carried out based on the dynamical mean-field theory (DMFT) in order to investigate the properties of correlated thin films for various values of the chemical potential, temperature, interaction strength, and applied transverse electric field. Application of a sufficiently strong field to a thin film at half filling leads to the appearance of conducting regions near the surfaces of the film, whereas in doped slabs the application of a field leads to a conductivity enhancement on one side of the film and a gradual transition to the insulating state on the opposite side. In addition to the inhomogeneous DMFT, a local density approximation (LDA) is considered in which the particle density n, quasiparticle residue Z, and spectral weight at the Fermi level A(ω=0) of each layer are approximated by a homogeneous bulk environment. A systematic comparison between the two approaches reveals that the less expensive LDA results are in good agreement with the DMFT approach, except close to the metal-to-insulator transition points and in the layers immediately at the film surfaces. LDA values for n are overall more reliable than those for Z and A(ω=0). The hysteretic behavior (memory effect) characteristic of the bulk doping driven Mott transition persists in the slab. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000373572700002 |
Publication Date |
2016-04-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
5 |
Open Access |
|
Notes |
; This work was partially funded by the Flemish Fund for Scientific Research (FWO Belgium) under FWO Grant No. G.0520.10 and the joint FWF (Austria)-FWO Grant No. GOG6616N, and by the SITOGA FP7 project. Most of the calculations were performed on KU Leuven's ThinKing HPC cluster provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:132872 |
Serial |
4167 |
Permanent link to this record |
|
|
|
Author |
Craco, L.; Carara, S.S.; da Silva Pereira, T.A.; Milošević, M.V. |
Title |
Electronic states in an atomistic carbon quantum dot patterned in graphene |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
155417 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We reveal the emergence of metallicKondo clouds in an atomistic carbon quantum dot, realized as a single-atom junction in a suitably patterned graphene nanoflake. Using density functional dynamical mean-field theory (DFDMFT) we show how correlation effects lead to striking features in the electronic structure of our device, and how those are enhanced by the electron-electron interactions when graphene is patterned at the atomistic scale. Our setup provides a well-controlled environment to understand the principles behind the orbital-selective Kondo physics and the interplay between orbital and spin degrees of freedom in carbon-based nanomaterials, which indicate new pathways for spintronics in atomically patterned graphene. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000373760900004 |
Publication Date |
2016-04-12 |
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 |
6 |
Open Access |
|
Notes |
; L.C.'s work is supported by CNPq (Proc. No. 307487/2014-8). Acknowledgment (L.C.) is also made to G. Seifert for discussions and the Department of Theoretical Chemistry at Technical University Dresden for hospitality. T.A.S.P. thanks PRONEX/CNPq/FAPEMAT 850109/2009 for financial support. M.V.M. acknowledges support from Research Foundation-Flanders (FWO), TOPBOF, and the CAPES-PVE program. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:133260 |
Serial |
4171 |
Permanent link to this record |
|
|
|
Author |
Mirzakhani, M.; Zarenia, M.; Ketabi, S.A.; da Costa, D.R.; Peeters, F.M. |
Title |
Energy levels of hybrid monolayer-bilayer graphene quantum dots |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
165410 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Often real samples of graphene consist of islands of both monolayer and bilayer graphene. Bound states in such hybrid quantum dots are investigated for (i) a circular single-layer graphene quantum dot surrounded by an infinite bilayer graphene sheet and (ii) a circular bilayer graphene quantum dot surrounded by an infinite single-layer graphene. Using the continuum model and applying zigzag boundary conditions at the single-layer-bilayer graphene interface, we obtain analytical results for the energy levels and the corresponding wave spinors. Their dependence on perpendicular magnetic and electric fields are studied for both types of quantum dots. The energy levels exhibit characteristics of interface states, and we find anticrossings and closing of the energy gap in the presence of a bias potential. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000373572700004 |
Publication Date |
2016-04-09 |
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 |
26 |
Open Access |
|
Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO)-CNPq project between Flanders and Brazil and the Brazilian Science Without Borders program. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:133261 |
Serial |
4174 |
Permanent link to this record |
|
|
|
Author |
Liao, Z.L.; Green, R.J.; Gauquelin, N.; Gonnissen, J.; Van Aert, S.; Verbeeck, J.; et al. |
Title |
Engineering properties by long range symmetry propagation initiated at perovskite heterostructure interface |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
|
Issue |
|
Pages |
1-25 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In epitaxial thin film systems, the crystal structure and its symmetry deviate from the bulk counterpart due to various mechanisms such as epitaxial strain and interfacial structural coupling, which induce an accompanying change in their properties. In perovskite materials, the crystal symmetry can be described by rotations of 6-fold coordinated transition metal oxygen octahedra, which are found to be altered at interfaces. Here, we unravel how the local oxygen octahedral coupling (OOC) at perovskite heterostructural interfaces initiates a different symmetry in epitaxial films and provide design rules to induce various symmetries in thin films by careful selecting appropriate combinations of substrate/buffer/film. Very interestingly we discovered that these combinations lead to symmetry changes throughout the full thickness of the film. Our results provide a deep insight into understanding the origin of induced crystal symmetry in a perovskite heterostructure and an intelligent route to achieve unique functional properties. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
|
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
12.124 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ lucian @ c:irua:134842 |
Serial |
4176 |
Permanent link to this record |
|
|
|
Author |
Lebedev, O.I.; Turner, S.; Caignaert, V.; Cherepanov, V.A.; Raveau, B. |
Title |
Exceptional layered ordering of cobalt and iron in perovskites |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
28 |
Issue |
28 |
Pages |
2907-2911 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000375810400005 |
Publication Date |
2016-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466 |
Call Number |
UA @ lucian @ c:irua:133640 |
Serial |
4178 |
Permanent link to this record |
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|
|
Author |
Cai, H.; Kang, J.; Sahin, H.; Chen, B.; Suslu, A.; Wu, K.; Peeters, F.; Meng, X.; Tongay, S. |
Title |
Exciton pumping across type-I gallium chalcogenide heterojunctions |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
27 |
Issue |
27 |
Pages |
065203 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Quasi-two-dimensional gallium chalcogenide heterostructures are created by transferring exfoliated few-layer GaSe onto bulk GaTe sheets. Luminescence spectroscopy measurements reveal that the light emission from underlying GaTe layers drastically increases on heterojunction regions where GaSe layers make contact with the GaTe. Density functional theory (DFT) and band offset calculations show that conduction band minimum (CBM) (valance band maximum (VBM)) values of GaSe are higher (lower) in energy compared to GaTe, forming type-I band alignment at the interface. Consequently, GaSe layers provide photo-excited electrons and holes to GaTe sheets through relatively large built-in potential at the interface, increasing overall exciton population and light emission from GaTe. Observed results are not specific to the GaSe/GaTe system but observed on GaS/GaSe heterolayers with type-I band alignment. Observed experimental findings and theoretical studies provide unique insights into interface effects across dissimilar gallium chalcogenides and offer new ways to boost optical performance by simple epitaxial coating. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000368897100008 |
Publication Date |
2016-01-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
15 |
Open Access |
|
Notes |
; This work was supported by the Arizona State University seeding program, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of the John M Cowley Center for High Resolution Electron Microscopy at Arizona State University. The authors thank Anupum Pant for useful discussions. We gratefully acknowledge the use of the facilities at the LeRoy Eyring Center for Solid State Science at Arizona State University. S Tongay acknowledges support from DMR-1552220. ; |
Approved |
Most recent IF: 3.44 |
Call Number |
UA @ lucian @ c:irua:131570 |
Serial |
4179 |
Permanent link to this record |
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|
|
Author |
Clima, S.; Chen, Y.Y.; Chen, C.Y.; Goux, L.; Govoreanu, B.; Degraeve, R.; Fantini, A.; Jurczak, M.; Pourtois, G. |
Title |
First-principles thermodynamics and defect kinetics guidelines for engineering a tailored RRAM device |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
119 |
Issue |
119 |
Pages |
225107 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Resistive Random Access Memories are among the most promising candidates for the next generation of non-volatile memory. Transition metal oxides such as HfOx and TaOx attracted a lot of attention due to their CMOS compatibility. Furthermore, these materials do not require the inclusion of extrinsic conducting defects since their operation is based on intrinsic ones (oxygen vacancies). Using Density Functional Theory, we evaluated the thermodynamics of the defects formation and the kinetics of diffusion of the conducting species active in transition metal oxide RRAM materials. The gained insights based on the thermodynamics in the Top Electrode, Insulating Matrix and Bottom Electrode and at the interfaces are used to design a proper defect reservoir, which is needed for a low-energy reliable switching device. The defect reservoir has also a direct impact on the retention of the Low Resistance State due to the resulting thermodynamic driving forces. The kinetics of the diffusing conducting defects in the Insulating Matrix determine the switching dynamics and resistance retention. The interface at the Bottom Electrode has a significant impact on the low-current operation and long endurance of the memory cell. Our first-principles findings are confirmed by experimental measurements on fabricated RRAM devices. Published by AIP Publishing. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000378925400035 |
Publication Date |
2016-06-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ lucian @ c:irua:134651 |
Serial |
4181 |
Permanent link to this record |
|
|
|
Author |
Calizzi, M.; Venturi, F.; Ponthieu, M.; Cuevas, F.; Morandi, V.; Perkisas, T.; Bals, S.; Pasquini, L. |
Title |
Gas-phase synthesis of Mg-Ti nanoparticles for solid-state hydrogen storage |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
18 |
Issue |
18 |
Pages |
141-148 |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
Abstract |
Mg-Ti nanostructured samples with different Ti contents were prepared via compaction of nanoparticles grown by inert gas condensation with independent Mg and Ti vapour sources. The growth set-up offered the option to perform in situ hydrogen absorption before compaction. Structural and morphological characterisation was carried out by X-ray diffraction, energy dispersive spectroscopy and electron microscopy. The formation of an extended metastable solid solution of Ti in hcp Mg was detected up to 15 at% Ti in the as-grown nanoparticles, while after in situ hydrogen absorption, phase separation between MgH2 and TiH2 was observed. At a Ti content of 22 at%, a metastable Mg-Ti-H fcc phase was observed after in situ hydrogen absorption. The co-evaporation of Mg and Ti inhibited nanoparticle coalescence and crystallite growth in comparison with the evaporation of Mg only. In situ hydrogen absorption was beneficial to subsequent hydrogen behaviour, studied by high pressure differential scanning calorimetry and isothermal kinetics. A transformed fraction of 90% was reached within 100 s at 300 degrees C during both hydrogen absorption and desorption. The enthalpy of hydride formation was not observed to differ from bulk MgH2. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000368755500014 |
Publication Date |
2015-11-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
31 |
Open Access |
Not_Open_Access |
Notes |
; Part of this work was supported by the COST Action MP1103 “Nanostructured materials for solid-state hydrogen storage”. ; |
Approved |
Most recent IF: 4.123 |
Call Number |
UA @ lucian @ c:irua:131589 |
Serial |
4184 |
Permanent link to this record |
|
|
|
Author |
Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M. |
Title |
Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
28 |
Issue |
28 |
Pages |
195301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000374394700007 |
Publication Date |
2016-04-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ lucian @ c:irua:133611 |
Serial |
4185 |
Permanent link to this record |
|
|
|
Author |
da Costa; Zarenia, M.; Chaves, A.; Pereira, J.M., Jr.; Farias, G.A.; Peeters, F.M. |
Title |
Hexagonal-shaped monolayer-bilayer quantum disks in graphene : a tight-binding approach |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
94 |
Issue |
94 |
Pages |
035415 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the tight-binding approach, we investigate confined states in two different hybrid monolayer-bilayer systems: (i) a hexagonal monolayer area surrounded by bilayer graphene in the presence of a perpendicularly applied electric field and (ii) a hexagonal bilayer graphene dot surrounded by monolayer graphene. The dependence of the energy levels on dot size and external magnetic field is calculated. We find that the energy spectrum for quantum dots with zigzag edges consists of states inside the gap which range from dot-localized states, edge states, to mixed states coexisting together, whereas for dots with armchair edges, only dot-localized states are observed. |
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 |
000379502200008 |
Publication Date |
2016-07-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
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Notes |
; This work was financially supported by CNPq, under contract NanoBioEstruturas No. 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation, under the process No. BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, the Brazilian Program Science Without Borders (CsF), and the Lemann Foundation. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:134947 |
Serial |
4190 |
Permanent link to this record |
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Author |
Neubert, S.; Mitoraj, D.; Shevlin, S.A.; Pulisova, P.; Heimann, M.; Du, Y.; Goh, G.K.L.; Pacia, M.; Kruczała, K.; Turner, S.; Macyk, W.; Guo, Z.X.; Hocking, R.K.; Beranek, R.; |
Title |
Highly efficient rutile TiO2 photocatalysts with single Cu(II) and Fe(III) surface catalytic sites |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
Volume |
4 |
Issue |
4 |
Pages |
3127-3138 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Highly active photocatalysts were obtained by impregnation of nanocrystalline rutile TiO2 powders with small amounts of Cu(II) and Fe(III) ions, resulting in the enhancement of initial rates of photocatalytic degradation of 4-chlorophenol in water by factors of 7 and 4, compared to pristine rutile, respectively. Detailed structural analysis by EPR and X-ray absorption spectroscopy (EXAFS) revealed that Cu(II) and Fe(III) are present as single species on the rutile surface. The mechanism of the photoactivity enhancement was elucidated by a combination of DFT calculations and detailed experimental mechanistic studies including photoluminescence measurements, photocatalytic experiments using scavengers, OH radical detection, and photopotential transient measurements. The results demonstrate that the single Cu(II) and Fe(III) ions act as effective cocatalytic sites, enhancing the charge separation, catalyzing “dark” redox reactions at the interface, thus improving the normally very low quantum yields of UV light-activated TiO2 photocatalysts. The exact mechanism of the photoactivity enhancement differs depending on the nature of the cocatalyst. Cu(II)-decorated samples exhibit fast transfer of photogenerated electrons to Cu(II/I) sites, followed by enhanced catalysis of dioxygen reduction, resulting in improved charge separation and higher photocatalytic degradation rates. At Fe(III)-modified rutile the rate of dioxygen reduction is not improved and the photocatalytic enhancement is attributed to higher production of highly oxidizing hydroxyl radicals produced by alternative oxygen reduction pathways opened by the presence of catalytic Fe(III/II) sites. Importantly, it was demonstrated that excessive heat treatment (at 450 degrees C) of photocatalysts leads to loss of activity due to migration of Cu(II) and Fe(III) ions from TiO2 surface to the bulk, accompanied by formation of oxygen vacancies. The demonstrated variety of mechanisms of photoactivity enhancement at single site catalyst-modified photocatalysts holds promise for developing further tailored photocatalysts for various applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000371077300040 |
Publication Date |
2015-12-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2050-7488; 2050-7496 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.867 |
Times cited |
44 |
Open Access |
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Notes |
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Approved |
Most recent IF: 8.867 |
Call Number |
UA @ lucian @ c:irua:132322 |
Serial |
4191 |
Permanent link to this record |
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Author |
Roesler, C.; Aijaz, A.; Turner, S.; Filippousi, M.; Shahabi, A.; Xia, W.; Van Tendeloo, G.; Muhler, M.; Fischer, R.A. |
Title |
Hollow Zn/Co Zeolitic Imidazolate Framework (ZIF) and Yolk-Shell Metal@Zn/Co ZIF nanostructures |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Chemistry: a European journal |
Abbreviated Journal |
Chem-Eur J |
Volume |
22 |
Issue |
22 |
Pages |
3304-3311 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Metal-organic frameworks (MOFs) feature a great possibility for a broad spectrum of applications. Hollow MOF structures with tunable porosity and multifunctionality at the nanoscale with beneficial properties are desired as hosts for catalytically active species. Herein, we demonstrate the formation of well-defined hollow Zn/Co-based zeolitic imidazolate frameworks (ZIFs) by use of epitaxial growth of Zn-MOF (ZIF-8) on preformed Co-MOF (ZIF-67) nanocrystals that involve in situ self-sacrifice/excavation of the Co-MOF. Moreover, any type of metal nanoparticles can be accommodated in Zn/Co-ZIF shells to generate yolk-shell metal@ZIF structures. Transmission electron microscopy and tomography studies revealed the inclusion of these nanoparticles within hollow Zn/Co-ZIF with dominance of the Zn-MOF as shell. Our findings lead to a generalization of such hollow systems that are working effectively to other types of ZIFs. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000371419200001 |
Publication Date |
2016-01-29 |
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 |
0947-6539 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.317 |
Times cited |
43 |
Open Access |
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Notes |
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Approved |
Most recent IF: 5.317 |
Call Number |
UA @ lucian @ c:irua:132347 |
Serial |
4192 |
Permanent link to this record |
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Author |
Felgen, N.; Naydenov, B.; Turner, S.; Jelezko, F.; Reithmaier, J.P.; Popov, C. |
Title |
Incorporation and study of SiV centers in diamond nanopillars |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Diamond and related materials |
Abbreviated Journal |
Diam Relat Mater |
Volume |
64 |
Issue |
64 |
Pages |
64-69 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report on the incorporation of SiV centers during hot filament chemical vapor deposition of diamond on top of diamond nanopillars with diameters down to 100 nm. The nanopillars themselves were prepared from nano crystalline diamond films by applying electron beam lithography and inductively coupled plasma reactive ion etching. The optical investigations revealed the presence of ensembles of SiV color centers incorporated during the overgrowth step. (C) 2016 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000374608100009 |
Publication Date |
2016-01-16 |
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 |
0925-9635 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.561 |
Times cited |
14 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.561 |
Call Number |
UA @ lucian @ c:irua:133623 |
Serial |
4193 |
Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Vasenko, A.S.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
Title |
Influence of disorder on superconducting correlations in nanoparticles |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
Volume |
29 |
Issue |
29 |
Pages |
605-609 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate how the interplay of quantum confinement and level broadening caused by disorder affects superconducting correlations in ultra-small metallic grains. We use the electron-phonon interaction-induced electron mass renormalization and the reduced static-path approximation of the BCS formalism to calculate the critical temperature as a function of the grain size. We show how the strong electron-impurity scattering additionally smears the peak structure in the electronic density of states of a metallic grain and imposes additional limits on the critical temperature under strong quantum confinement. |
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 |
000371089500013 |
Publication Date |
2016-01-08 |
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 |
1557-1939 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.18 |
Times cited |
7 |
Open Access |
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Notes |
; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Flemish Science Foundation (FWO-Vl), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO-Vl. ; |
Approved |
Most recent IF: 1.18 |
Call Number |
UA @ lucian @ c:irua:132286 |
Serial |
4195 |
Permanent link to this record |
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Author |
Zhang, B.; Dugas, R.; Rousse, G.; Rozier, P.; Abakumov, A.M.; Tarascon, J.-M. |
Title |
Insertion compounds and composites made by ball milling for advanced sodium-ion batteries |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
7 |
Issue |
7 |
Pages |
10308 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Sodium-ion batteries have been considered as potential candidates for stationary energy storage because of the low cost and wide availability of Na sources. However, their future commercialization depends critically on control over the solid electrolyte interface formation, as well as the degree of sodiation at the positive electrode. Here we report an easily scalable ball milling approach, which relies on the use of metallic sodium, to prepare a variety of sodium-based alloys, insertion layered oxides and polyanionic compounds having sodium in excess such as the Na4V2(PO4)(2)F-3 phase. The practical benefits of preparing sodium-enriched positive electrodes as reservoirs to compensate for sodium loss during solid electrolyte interphase formation are demonstrated by assembling full C/P'2-Na-1[Fe0.5Mn0.5]O-2 and C/'Na3+xV2(PO4)(2)F-3' sodium-ion cells that show substantial increases (>10%) in energy storage density. Our findings may offer electrode design principles for accelerating the development of the sodium-ion technology. |
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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 |
000369021400002 |
Publication Date |
2016-01-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2041-1723 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
104 |
Open Access |
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Notes |
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Approved |
Most recent IF: 12.124 |
Call Number |
UA @ lucian @ c:irua:131599 |
Serial |
4197 |
Permanent link to this record |
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Author |
Van de Put, M.L.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Fischetti, M.V. |
Title |
Inter-ribbon tunneling in graphene: An atomistic Bardeen approach |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
119 |
Issue |
119 |
Pages |
214306 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A weakly coupled system of two crossed graphene nanoribbons exhibits direct tunneling due to the overlap of the wavefunctions of both ribbons. We apply the Bardeen transfer Hamiltonian formalism, using atomistic band structure calculations to account for the effect of the atomic structure on the tunneling process. The strong quantum-size confinement of the nanoribbons is mirrored by the one-dimensional character of the electronic structure, resulting in properties that differ significantly from the case of inter-layer tunneling, where tunneling occurs between bulk two-dimensional graphene sheets. The current-voltage characteristics of the inter-ribbon tunneling structures exhibit resonance, as well as stepwise increases in current. Both features are caused by the energetic alignment of one-dimensional peaks in the density-of-states of the ribbons. Resonant tunneling occurs if the sign of the curvature of the coupled energy bands is equal, whereas a step-like increase in the current occurs if the signs are opposite. Changing the doping modulates the onset-voltage of the effects as well as their magnitude. Doping through electrostatic gating makes these structures promising for application towards steep slope switching devices. Using the atomistic empirical pseudopotentials based Bardeen transfer Hamiltonian method, inter-ribbon tunneling can be studied for the whole range of two-dimensional materials, such as transition metal dichalcogenides. The effects of resonance and of step-like increases in the current we observe in graphene ribbons are also expected in ribbons made from these alternative two-dimensional materials, because these effects are manifestations of the one-dimensional character of the density-of-states. Published by AIP Publishing. |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000378923100022 |
Publication Date |
2016-06-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
6 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ lucian @ c:irua:134652 |
Serial |
4198 |
Permanent link to this record |
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Author |
O'Sullivan, M.; Hadermann, J.; Dyer, M.S.; Turner, S.; Alaria, J.; Manning, T.D.; Abakumov, A.M.; Claridge, J.B.; Rosseinsky, M.J. |
Title |
Interface control by chemical and dimensional matching in an oxide heterostructure |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2016 |
Publication |
Nature chemistry |
Abbreviated Journal |
Nat Chem |
Volume |
8 |
Issue |
8 |
Pages |
347-353 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Interfaces between different materials underpin both new scientific phenomena, such as the emergent behaviour at oxide interfaces, and key technologies, such as that of the transistor. Control of the interfaces between materials with the same crystal structures but different chemical compositions is possible in many materials classes, but less progress has been made for oxide materials with different crystal structures. We show that dynamical self-organization during growth can create a coherent interface between the perovskite and fluorite oxide structures, which are based on different structural motifs, if an appropriate choice of cations is made to enable this restructuring. The integration of calculation with experimental observation reveals that the interface differs from both the bulk components and identifies the chemical bonding requirements to connect distinct oxide structures. |
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 |
000372505500013 |
Publication Date |
2016-02-01 |
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 |
1755-4330; 1755-4349 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
25.87 |
Times cited |
28 |
Open Access |
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Notes |
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Approved |
Most recent IF: 25.87 |
Call Number |
UA @ lucian @ c:irua:133189 |
Serial |
4199 |
Permanent link to this record |