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Records |
Links |
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Author |
Raveau, B.; Michel, C.; Hervieu, M.; Van Tendeloo, G.; Maignan, A. |
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| |
Title |
Stabilization of mercury-based superconductors by foreign cations |
Type |
A1 Journal article |
| |
Year |
1994 |
Publication |
Annales de chimie (1914)
T2 – 4th North-African Materials Science Symposium (JMSM 94), NOV 23-24, 1994, CASABLANCA, MOROCCO |
Abbreviated Journal |
4th North-African Materials Science Symposium (JMSM 94), NOV 23-24, 1994, CASABLANCA, MOROCCO |
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| |
Volume |
19 |
Issue |
7-8 |
Pages |
487-492 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract  |
The recently discovered superconducting mercury-based cuprates HgBa2Can-1CunO2n+2+delta have proved difficult to synthesize as single phases and are sensitive to environment (CO2, moisture). The present paper gives an overview of new series mercury based superconductors, whose stabilisation is based on the fact that a foreign cation with a higher valency than Hg(II) must be introduced in the mercury layers, in order to fill up partially the oxygen vacancies of these layers. By this method, several new series of superconductors involving strontium instead of barium with critical temperatures ranging from 27 K to 95 K have been isolated : Hg0.5Bi0.5Sr2-xLaxCuO4+delta, Hg(0.5)Bi(0.5)Sr(2)Ca(1-x)R(x)Cu(2)O(6+delta) (R Y, Nd, Pr), Pb0.7Hg0.3Sr2-xLaxCuO4+delta, Pb(0.7)Hg(0.3)Sr(2)Ca(1-x)R(x)Cu(2)O(6+delta) (R = Y, Nd) Hg(1-x)Pr(x)Sr(2)A(1-x')Pr(x') Cu2O6+delta (A = Sr, Ca), Pb0.7Hg0.3Sr2Cu2CO3O7 and Hg1-xCrxSr2CuO4+delta. The behaviour of the praseodymium cuprates that exhibit a rather sharp transition and reach a Tc of 85 K is especially discussed. A method to synthesize new ''Ba-Hg'' superconducting cuprates with the 1212 structure at normal pressure with a Tc up to 110 K is also presented. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Paris |
Editor |
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Language |
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Wos |
A1994RC75300027 |
Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0151-9107 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
2 |
Open Access |
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Notes |
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Approved |
PHYSICS, APPLIED 28/145 Q1 # |
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Call Number |
UA @ lucian @ c:irua:104472 |
Serial |
3137 |
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| Permanent link to this record |
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Author |
Arisnabarreta, N.; Hao, Y.; Jin, E.; Salame, A.; Muellen, K.; Robert, M.; Lazzaroni, R.; Van Aert, S.; Mali, K.S.; De Feyter, S. |
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Title |
Single-layered imine-linked porphyrin-based two-dimensional covalent organic frameworks targeting CO₂ reduction |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Advanced energy materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The reduction of carbon dioxide (CO2) using porphyrin-containing 2D covalent organic frameworks (2D-COFs) catalysts is widely explored nowadays. While these framework materials are normally fabricated as powders followed by their uncontrolled surface heterogenization or directly grown as thin films (thickness >200 nm), very little is known about the performance of substrate-supported single-layered (approximate to 0.5 nm thickness) 2D-COFs films (s2D-COFs) due to its highly challenging synthesis and characterization protocols. In this work, a fast and straightforward fabrication method of porphyrin-containing s2D-COFs is demonstrated, which allows their extensive high-resolution visualization via scanning tunneling microscopy (STM) in liquid conditions with the support of STM simulations. The as-prepared single-layered film is then employed as a cathode for the electrochemical reduction of CO2. Fe porphyrin-containing s2D-COF@graphite used as a single-layered heterogeneous catalyst provided moderate-to-high carbon monoxide selectivity (82%) and partial CO current density (5.1 mA cm(-2)). This work establishes the value of using single-layered films as heterogene ous catalysts and demonstrates the possibility of achieving high performance in CO2 reduction even with extremely low catalyst loadings. |
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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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Wos |
001177577200001 |
Publication Date |
2024-02-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1614-6832; 1614-6840 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:204856 |
Serial |
9172 |
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| Permanent link to this record |
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Author |
Coeck, R.; Meeprasert, J.; Li, G.; Altantzis, T.; Bals, S.; Pidko, E.A.; De Vos, D.E. |
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Title |
Gold and silver-catalyzed reductive amination of aromatic carboxylic acids to benzylic amines |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
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| |
Volume |
11 |
Issue |
13 |
Pages |
7672-7684 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
The reductive amination of benzoic acid and its derivatives would be an effective addition to current synthesis methods for benzylamine. However, with current technology it is very difficult to keep the aromaticity intact when starting from benzoic acid, and salt wastes are often generated in the process. Here, we report a heterogeneous catalytic system for such a reductive amination, requiring solely H-2 and NH3 as the reactants. The Ag/TiO2 or Au/TiO2 catalysts can be used multiple times, and very little noble metal is required, only 0.025 mol % Au. The catalysts are bifunctional: the support catalyzes the dehydration of both the ammonium carboxylate to the amide and of the amide to the nitrile, while the sites at the metal-support interface promote the hydrogenation of the in situ generated nitrile. Yields of up to 92% benzylamine were obtained. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000670659900005 |
Publication Date |
2021-06-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
10.614 |
Times cited |
16 |
Open Access |
OpenAccess |
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| |
Notes |
R.C. thanks the FWO for his SB PhD fellowship. D.E.D.V. acknowledges FWO for research project funding, as well as KU Leuven for funding in the Metusalem program Casas. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO). T.A. acknowledges funding from the University of Antwerp Research fund (BOF). E.A.P. acknowledges the support from the European Research Council (ERC Consolidator grant #725686 DeliCAT). J.M. acknowledges financial support through the Royal Thai Government Scholarship. DFT calculations on SURFsara supercomputer facilities were performed with support from the Netherlands Organization for Scientific Research (NWO).; sygmaSB |
Approved |
Most recent IF: 10.614 |
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| |
Call Number |
UA @ admin @ c:irua:179851 |
Serial |
6840 |
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| Permanent link to this record |
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Author |
Ben Abdallah, M.A.; Bacchi, A.; Parisini, A.; Canossa, S.; Bergamonti, L.; Balestri, D.; Kamoun, S. |
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| |
Title |
Crystal structure, vibrational, electrical, optical and DFT study of C₂H₁0N₂(IO₃)₂.HIO₃ |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Molecular Structure |
Abbreviated Journal |
J Mol Struct |
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| |
Volume |
1215 |
Issue |
|
Pages |
128254-12 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The reinvestigation of the EDA-HIO3-H2O system using a different stoichiometric ratio gives rise to a new iodate salt C2H10N2(IO3)(2 center dot)HIO3 denoted as EBIMIA. In this study, we reported the structural properties of ethylenediammonium bis iodate mono iodic acid using X-ray powder and single crystal diffraction at room temperature. The Hirshfeld and the potential energy surface analysis reveal that I center dot center dot center dot O and N-H center dot center dot center dot O are the most noticeable interactions that took place inside the crystal and contribute to the cohesion and stability of the synthesized compound. The DSC measurement shows that this iodate salt undergoes two structural phase transitions, the first occurs at T = 290 K while the second occurs at T = 363 K. However, the dielectric analysis confirms only the second transition because it lies in the studied temperature domain 338-413K. Besides, the impedance data obey a circuit model consisting of a parallel combination of a bulk resistance and CPE. The frequency dispersion of the conductivity follows Jonscher's law and the charge carrier transport may be interpreted using the correlation barrier hopping mechanism (CBH). Finally, the electronic properties and the vibrational analysis of this novel iodate salt are studied using DFT and compared to the experimental data given by the FT-IR, Raman and UV-visible spectroscopies. (C) 2020 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000537221300012 |
Publication Date |
2020-04-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0022-2860 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
3.8 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
; The authors are grateful to Pr. Giovani Predieri, Pr. Pier Paolo Lottici, and Pr. Danilo Bersani, for their help with the vibrational measurement. Moreover, authors wish to thank, Pr. Salvatore Vantaggio and Dr. Silvio Scaravonati for their contribution in carrying out the impedance spectroscopy measurements. The authors acknowledge also the Analytical Chemistry, Cultural Heritage, Inorganic Chemistry and Crystallography Unit (SCVSA department, university of Parma, Italy) and the Tunisian Ministry of Higher Education and Scientific Research (LR11ES46) for their support. ; |
Approved |
Most recent IF: 3.8; 2020 IF: 1.753 |
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| |
Call Number |
UA @ admin @ c:irua:170148 |
Serial |
6480 |
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| Permanent link to this record |
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Author |
Vanhumbeeck, J.-F.; Tian, H.; Schryvers, D.; Proost, J. |
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Title |
Stress-assisted crystallisation in anodic titania |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Corrosion science |
Abbreviated Journal |
Corros Sci |
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| |
Volume |
53 |
Issue |
4 |
Pages |
1269-1277 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The relationship between the microstructural and internal stress evolution during Ti anodising is discussed. Samples anodised galvanostatically to 12 V and 40 V, corresponding to different stages of the internal stress evolution, were examined by in-plane and cross-section transmission electron microscopy. Electron diffraction patterns have been complemented with stoichiometry data obtained from energy loss near edge structure spectra. The sample anodised to 40 V was observed to consist of two regions, with a crystallised inner region adjacent to the metal/oxide interface. Crystallisation of this region is associated with the presence of large compressive internal stresses which build up during anodising up to 12 V. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000288972000016 |
Publication Date |
2010-12-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0010-938X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.245 |
Times cited |
11 |
Open Access |
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| |
Notes |
Fwo |
Approved |
Most recent IF: 5.245; 2011 IF: 3.734 |
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| |
Call Number |
UA @ lucian @ c:irua:88385 |
Serial |
3177 |
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| Permanent link to this record |
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Author |
Schuddinck, W.; Van Tendeloo, G.; Barnabé, A.; Hervieu, M.; Raveau, B. |
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Title |
Relation between structure, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites |
Type |
A1 Journal article |
| |
Year |
2000 |
Publication |
Journal of magnetism and magnetic materials
T2 – Symposium G Material Physics Issues and Applications of Magnetic Oxides, at the E-MRS Spring Meeting, JUN 01-04, 1999, Strasbourg, France |
Abbreviated Journal |
J Magn Magn Mater |
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| |
Volume |
211 |
Issue |
1-3 |
Pages |
105-110 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The relationships between incommensurability, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites have been studied by electron diffraction and lattice imaging versus temperature with 0.02 less than or equal to x less than or equal to 0.07. All compositions show an incommensurate superstructure over the whole temperature domain, despite the fact that they are ferromagnetic and conductive below 140 K, The q-vector (1/2 – delta)a* decreases with increasing temperature for all compositions x. For a given temperature q also decreases with x. Lattice images obtained at low temperature give a clear view of the characteristics of the incommensurate structure. They also provide a better understanding of the charge ordering process. The low-temperature form of the Cr-doped manganites is not a perfectly doubled cell [[2a(p)root 2 x 2a(p) x a(p)root 2]], but defects inducing a tripled cell occur pseudo-periodically. (C) 2000 Elsevier Science B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000085772100017 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-8853; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.63 |
Times cited |
16 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.63; 2000 IF: 0.996 |
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Call Number |
UA @ lucian @ c:irua:104256 |
Serial |
2858 |
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| Permanent link to this record |
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Author |
Sun, C.; Liao, X.; Xia, F.; Zhao, Y.; Zhang, L.; Mu, S.; Shi, S.; Li, Y.; Peng, H.; Van Tendeloo, G.; Zhao, K.; Wu, J. |
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Title |
High-voltage cycling induced thermal vulnerability in LiCoO₂ cathode : cation loss and oxygen release driven by oxygen vacancy migration |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
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| |
Volume |
14 |
Issue |
5 |
Pages |
6181-6190 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The release of the lattice oxygen due to the thermal degradation of layered lithium transition metal oxides is one of the major safety concerns in Li-ion batteries. The oxygen release is generally attributed to the phase transitions from the layered structure to spinel and rocksalt structures that contain less lattice oxygen. Here, a different degradation pathway in LiCoO2 is found, through oxygen vacancy facilitated cation migration and reduction. This process leaves undercoordinated oxygen that gives rise to oxygen release while the structure integrity of the defect-free region is mostly preserved. This oxygen release mechanism can be called surface degradation due to the kinetic control of the cation migration but has a slow surface to bulk propagation with continuous loss of the surface cation ions. It is also strongly correlated with the high-voltage cycling defects that end up with a significant local oxygen release at low temperatures. This work unveils the thermal vulnerability of high-voltage Li-ion batteries and the critical role of the surface fraction as a general mitigating approach. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000537682300101 |
Publication Date |
2020-04-17 |
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Series Editor |
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Series Title |
|
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 |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
17.1 |
Times cited |
8 |
Open Access |
Not_Open_Access |
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Notes |
; C.S., X.L., and F.X. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (21905169). The S/TEM work was performed at the Nanostructure Research Center (NRC), which is supported by the Fundamental Research Funds for the Central Universities (WUT: 2019III012GX), the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, and the State Key Laboratory of Silicate Materials for Architectures (all of the laboratories are at Wuhan University of Technology). ; |
Approved |
Most recent IF: 17.1; 2020 IF: 13.942 |
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Call Number |
UA @ admin @ c:irua:170246 |
Serial |
6537 |
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| Permanent link to this record |
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Author |
Buffière, M.; Brammertz, G.; Sahayaraj, S.; Batuk, M.; Khelifi, S.; Mangin, D.; El Mel, A.A.; Arzel, L.; Hadermann, J.; Meuris, M.; Poortmans, J.; |
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Title |
KCN chemical etch for interface engineering in Cu2ZnSnSe4 solar cells |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
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| |
Volume |
7 |
Issue |
7 |
Pages |
14690-14698 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The removal of secondary phases from the surface of the kesterite crystals is one of the major challenges to improve the performances of Cu2ZnSn(S,Se)(4) (CZTSSe) thin film solar cells. In this Contribution, the KCN/KOH Chemical etching approach, originally developed for the removal of CuxSe phases in Cu(In,Ga)(S,Se)(2) thin films) is applied to CZTSe absorbers exhibiting various chemical compositions. Two distinct electrical behaviors were observed on CZTSe/CdS solar cells after treatment: (i) the improvement of the fill factor (FF) after 30 s of etching for the CZTSe absorbers showing initially a distortion of the electrical characteristic; (ii) the progressive degradation Of the FF after long treatment time for all Cu-poor CZTSe solar cell samples. The first effect can be attributed to the action of KCN on the absorber, that is found to clean the absorber free surface from most of the secondary phases surrounding the kesterite grains (e.g., Se-0, CuxSe, SnSex, SnO2, Cu2SnSe3 phases, excepting the ZnSe-based phases). The second observation was identified as a consequence of the preferential etching of Se, Sn, and Zn from the CZTSe surface by the KOH solution, combined with the modification of the alkali content of the absorber. The formation of a Cu-rich shell at the absorber/buffer layer interface, leading to the increase of the recombination rate at the interface, and the increase in the doping of the absorber layer after etching are found to be at the origin of the deterioration of the FF of the solar cells. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000358395200019 |
Publication Date |
2015-06-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
7.504 |
Times cited |
34 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
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Call Number |
c:irua:127153 |
Serial |
1755 |
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| Permanent link to this record |
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Author |
Ghica, C.; Nistor, L.; Bender, H.; Steegen, A.; Lauwers, A.; Maex, K.; van Landuyt, J. |
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Title |
In situ transmission electron microscopy study of the silicidation process in Co thin films on patterned (001) Si substrates |
Type |
A1 Journal article |
| |
Year |
2001 |
Publication |
Journal of materials research |
Abbreviated Journal |
J Mater Res |
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| |
Volume |
16 |
Issue |
3 |
Pages |
701-708 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The results of an in situ transmission electron microscopy study of the formation of Co-silicides on patterned (001) Si substrates are discussed. It is shown that the results of the in situ heating experiments agreed very well with the data based on standard rapid thermal annealing experiments. Fast heating rates resulted in better definition of the silicide lines. Also, better lines were obtained for samples that received already a low-temperature ex situ anneal. A Ti cap layer gave rise to a higher degree of epitaxy in the CoSi2 silicide. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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| |
Language |
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Wos |
000167407200011 |
Publication Date |
2008-03-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
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| |
ISSN |
0884-2914;2044-5326; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.673 |
Times cited |
4 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 1.673; 2001 IF: 1.539 |
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| |
Call Number |
UA @ lucian @ c:irua:103926 |
Serial |
1588 |
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| Permanent link to this record |
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Author |
Pearce, P.E.; Rousse, G.; Karakulina, O.M.; Hadermann, J.; Van Tendeloo, G.; Foix, D.; Fauth, F.; Abakumov, A.M.; Tarascon, J.-M. |
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Title |
β-Na1.7IrO3: A Tridimensional Na-Ion Insertion Material with a Redox Active Oxygen Network |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
30 |
Issue |
10 |
Pages |
3285-3293 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The revival of the Na-ion battery concept has prompted an intense search for new high capacity Na-based positive electrodes. Recently, emphasis has been placed on manipulating Na-based layered compounds to trigger the participation of the anionic network. We further explored this direction and show the feasibility of achieving anionic-redox activity in three-dimensional Na-based compounds. A new 3D β-Na1.7IrO3 phase was synthesized in a two-step process, which involves first the electrochemical removal of Li from β-Li2IrO3 to produce β-IrO3, which is subsequently reduced by electrochemical Na insertion. We show that β-Na1.7IrO3 can reversibly uptake nearly 1.3 Na+ per formula unit through an uneven voltage profile characterized by the presence of four plateaus related to structural transitions. Surprisingly, the β-Na1.7IrO3 phase was found to be stable up to 600 °C, while it could not be directly synthesized via conventional synthetic methods. Although these Na-based iridate phases are of limited practical interest, they help to understand how introducing highly polarizable guest ions (Na+) into host rocksalt-derived oxide structures affects the anionic redox mechanism. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000433403800014 |
Publication Date |
2018-05-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
OpenAccess |
|
| |
Notes |
The authors thank A. Perez for fruitful discussions and his valuable help in synchrotron XRD experiment and Matthieu Courty for carrying out the DSC measurements. The authors also greatly thank Matthieu Saubanère and Marie-Liesse Doublet for valuable discussions on theoretical aspects of this work. This work is based on experiments performed on the Materials Science and Powder Diffraction Beamline at ALBA synchrotron (Proposal 2016091814), Cerdanyola del Vallès, E- 08290 Barcelona, Spain. J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014)/ERC Grant- Project 670116-ARPEMA. G.R. acknowledges funding from ANR DeliRedox. O.M.K., J.H., and A.M.A. are grateful to FWO Vlaanderen for financial support under Grant G040116N. |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
EMAT @ emat @c:irua:152048 |
Serial |
4996 |
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| Permanent link to this record |
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| |
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Author |
Baral, P.; Orekhov, A.; Dohmen, R.; Coulombier, M.; Raskin, J.P.; Cordier, P.; Idrissi, H.; Pardoen, T. |
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| |
Title |
Rheology of amorphous olivine thin films characterized by nanoindentation |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Acta Materialia |
Abbreviated Journal |
Acta Mater |
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| |
Volume |
219 |
Issue |
|
Pages |
117257 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The rheological properties of amorphous olivine thin films deposited by pulsed laser deposition have been studied based on ambient temperature nanoindentation under constant strain-rate as well as re-laxation conditions. The amorphous olivine films exhibit a viscoelastic-viscoplastic behavior with a significant rate dependency. The strain-rate sensitivity m is equal to similar to 0 . 05 which is very high for silicates, indicating a complex out-of-equilibrium structure. The minimum apparent activation volume determined from nanoindentation experiments corresponds to Mg and Fe atomic metallic sites in the (Mg,Fe)(2)SiO4 crystalline lattice. The ambient temperature creep behavior of the amorphous olivine films differs very much from the one of single crystal olivine. This behavior directly connects to the recent demonstration of the activation of grain boundary sliding in polycrystalline olivine following grain boundary amorphization under high-stress. (C) 2021 The Authors. Published by Elsevier Ltd on behalf of Acta Materialia Inc. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000706867800004 |
Publication Date |
2021-08-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1359-6454 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.301 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
|
Approved |
Most recent IF: 5.301 |
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| |
Call Number |
UA @ admin @ c:irua:182592 |
Serial |
6882 |
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| Permanent link to this record |
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| |
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Author |
Idrissi, H.; Bollinger, C.; Boioli, F.; Schryvers, D.; Cordier, P. |
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Title |
Low-temperature plasticity of olivine revisited with in situ TEM nanomechanical testing |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Science Advances |
Abbreviated Journal |
|
|
| |
Volume |
2 |
Issue |
2 |
Pages |
e1501671-e1501671 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The rheology of the lithospheric mantle is fundamental to understanding how mantle convection couples with plate tectonics. However, olivine rheology at lithospheric conditions is still poorly understood because experiments are difficult in this temperature range where rocks and mineral become very brittle. We combine techniques of quantitative in situ tensile testing in a transmission electron microscope and numerical modeling of dislocation dynamics to constrain the low-temperature rheology of olivine. We find that the intrinsic ductility of olivine at low temperature is significantly lower than previously reported values, which were obtained under strain-hardened conditions. Using this method, we can anchor rheological laws determined at higher temperature and can provide a better constraint on intermediate temperatures relevant for the lithosphere. More generally, we demonstrate the possibility of characterizing the mechanical properties of specimens, which can be available in the form of submillimeter-sized particles only. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000379620200043 |
Publication Date |
2016-03-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2375-2548 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
32 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:134983 |
Serial |
4202 |
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| Permanent link to this record |
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| |
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Author |
Esken, D.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Fischer, R.A. |
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Title |
Au@ZIFs: stabilization and encapsulation of cavity-size matching gold clusters inside functionalized Zeolite Imidazolate Frameworks, ZIFs |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
22 |
Issue |
23 |
Pages |
6393-6401 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The selective formation and stabilization of very small, naked metal particles inside the cavities of metal organic frameworks (MOFs) and the simultaneous realization of an even distribution of the particles throughout the crystalline MOF host matrix over a wide range of metal loading are challenging goals. MOFs reveal high specific surface areas, tunable pore sizes, and organic linkers, which are able to interact with guests. The chemically very robust zeolite imidazolate frameworks (ZIFs) are a subclass of MOFs. We chose the microporous sodalite-like ZIF-8 (Zn(MelM)(2); IM = imidazolate) and ZIF-90 (Zn(ICA)(2); ICA = imidazolate-2-carboxyaldehyde) as host matrices to influence the dispersion of imbedded gold nanoparticles (Au NPs). The metal loading was achieved via gas phase infiltration of [Au(CO)Cl] followed by a thermal hydrogenation step to form the Au NPs. Low-dose high-resolution transmission electron microscopy ((HR)TEM) and electron tomography reveal a homogeneous distribution of Au NPs throughout the ZIF matrix. The functional groups of ZIF-90 direct the anchoring of intermediate Au species and stabilize drastically smaller and quite monodisperse Au NPs in contrast to the parent not functionalized ZIF-8. The particles can be very small, match the cavity size and approach defined molecular clusters of magic numbers, i.e., Au(55), independently from the level of loading. Post-synthetic oxidation of the aldehyde groups to yield alkyl esters by the adjacent, catalytically active metal NPs is presented as a new concept of encapsulating nanoparticles inside MOFs and allows multiple steps of metal loadings without decomposition of the MOF. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000284975100025 |
Publication Date |
2010-11-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
194 |
Open Access |
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| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
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| |
Call Number |
UA @ lucian @ c:irua:95530 |
Serial |
208 |
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| Permanent link to this record |
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Author |
Adamson, P.; Hadermann, J.; Smura, C.F.; Rutt, O.J.; Hyett, G.; Free, D.G.; Clarke, S.J. |
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Title |
Competing magnetic structures and the evolution of copper ion/vacancy ordering with composition in the manganite oxide chalcogenides Sr2MnO2Cu1.5(S1-xSex)2 |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
24 |
Issue |
14 |
Pages |
2802-2816 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The series Sr2MnO2Cu1.5(S1-xSex)(2) (0 <= x <= 1) contains mixed-valent Mn ions (Mn2+/Mn3+) in MnO2 sheets which are separated by copper-deficient antifluorite-type Cu(2-delta)Ch(2) layers with delta similar to 0.5. The compounds crystallize in the structure type first described for Sr2Mn3Sb2O2 and are described in the I4/mmm space group at ambient temperatures. Below about 250 K, ordering between Cu+ ions and tetrahedral vacancies occurs which is long-range and close to complete in the sulfide-containing end member of the series Sr2MnO2Cu1.5S2 but which occurs over shorter length scales as the selenide content increases. The superstructure is an orthorhombic 2 root 2a x root 2a x c expansion in Ibam of the room temperature cell. For x > 0.3 there are no superstructure reflections evident in the X-ray or neutron diffraction patterns, and the I4/mmm description is valid for the average structure at all temperatures. However, in the pure selenide end member, Sr2MnO2Cu1.5Se2, diffuse scattering in electron diffractograms and modulation in high resolution lattice image profiles may arise from short-range Cu/vacancy order. All members of the series exhibit long-range magnetic order. In the sulfide-rich end member and in compounds with x < 0.1 in the formula Sr2MnO2Cu1.5(S1-xSex)(2), which show well developed superstructures due to long-range Cu/vacancy order, the magnetic structure has a (1/4 1/4 0) propagation vector in which ferromagnetic zigzag chains of Mn moments in the MnO2 sheets are coupled antiferromagnetically in an arrangement described as the CE-type magnetic structure and found in many mixed-valent perovskite and Ruddlesden-Popper type oxide manganites. In these cases the magnetic cell is an a x 2b x c expansion of the low temperature Ibam structural cell. For x >= 0.2 in the formula Sr2MnO2Cu1.5(S1-xSex)(2) the magnetic structure has a (0 0 0) propagation vector and is similar to the A-type structure, also commonly adopted by some perovskite-related manganites, in which the Mn moments in the MnO2 sheets are coupled ferromagnetically and long-range antiferromagnetic order results from antiferromagnetic coupling between planes. In the region of the transition between the two different structural and magnetic long-range ordering schemes (0.1 < x < 0.2) the two magnetic structures coexist in the same sample. The evolution of the competition between magnetic ordering schemes and the length scale of the structural order with composition in Sr2MnO2Cu1.5(S1-xSex)(2) suggest that the changes in magnetic and structural order are related consequences of the introduction of chemical disorder. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000306674200024 |
Publication Date |
2012-06-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
9.466 |
Times cited |
11 |
Open Access |
|
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
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| |
Call Number |
UA @ lucian @ c:irua:100839 |
Serial |
435 |
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| Permanent link to this record |
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Author |
Chen, Z.; Tan, Z.; Ji, G.; Schryvers, D.; Ouyang, Q.; Li, Z. |
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Title |
Effect of interface evolution on thermal conductivity of vacuum hot pressed SiC/Al composites |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Advanced engineering materials |
Abbreviated Journal |
Adv Eng Mater |
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| |
Volume |
17 |
Issue |
17 |
Pages |
1076-1084 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The SiC/Al composites have been fabricated by a vacuum hot pressing (VHP) process in order to study the effect of interface evolution on the global thermal conductivity (TC). By optimizing the VHP parameters of sintering temperature and time, the three different kinds of SiC/Al interface configurations, that is, non-bonded, diffusion-bonded, and reaction-bonded interfaces, are formed and identified by measurement of relative density, X-ray diffraction, scanning and (high-resolution) transmission electron microscopy. The VHPed composite sintered at 655 °C for 60 min is fully dense and presents a tightly-adhered and clean SiC/Al interface at the nanoscale, the ideal diffusion-bonded interface being the most favorable for minimizing interfacial thermal resistance, which in turn results in the highest TC of around 270 W/mK. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000357680700019 |
Publication Date |
2015-01-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1438-1656; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.319 |
Times cited |
9 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 2.319; 2015 IF: 1.758 |
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| |
Call Number |
c:irua:123000 |
Serial |
818 |
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| Permanent link to this record |
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Author |
Verbeeck, J.; Hébert; Rubino, S.; Novák, P.; Rusz, J.; Houdellier, F.; Gatel, C.; Schattschneider, P. |
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Title |
Optimal aperture sizes and positions for EMCD experiments |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
108 |
Issue |
9 |
Pages |
865-872 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The signal-to-noise ratio (SNR) in energy-loss magnetic chiral dichroism (EMCD)the equivalent of X-ray magnetic circular dichroism (XMCD) in the electron microscopeis optimized with respect to the detector shape, size and position. We show that an important increase in SNR over previous experiments can be obtained when taking much larger detector sizes. We determine the ideal shape of the detector but also show that round apertures are a good compromise if placed in their optimal position. We develop the theory for a simple analytical description of the EMCD experiment and then apply it to dynamical multibeam Bloch wave calculations and to an experimental data set. In all cases it is shown that a significant and welcome improvement of the SNR is possible. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000258747600009 |
Publication Date |
2008-03-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
|
Edition |
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| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
27 |
Open Access |
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| |
Notes |
This work was supported by the European Commission under contract no. 508971 CHIRALTEM. J.V. and F.H. thank the financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. Thanks to J.P. Morniroli for making the Fe sample available. |
Approved |
Most recent IF: 2.843; 2008 IF: 2.629 |
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| |
Call Number |
UA @ lucian @ c:irua:76492UA @ admin @ c:irua:76492 |
Serial |
2480 |
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| Permanent link to this record |
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Author |
Madsen, J.; Pennycook, T.J.; Susi, T. |
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Title |
ab initio description of bonding for transmission electron microscopy |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
231 |
Issue |
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Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The simulation of transmission electron microscopy (TEM) images or diffraction patterns is often required to interpret their contrast and extract specimen features. This is especially true for high-resolution phase-contrast imaging of materials, but electron scattering simulations based on atomistic models are widely used in materials science and structural biology. Since electron scattering is dominated by the nuclear cores, the scattering potential is typically described by the widely applied independent atom model. This approximation is fast and fairly accurate, especially for scanning TEM (STEM) annular dark-field contrast, but it completely neglects valence bonding and its effect on the transmitting electrons. However, an emerging trend in electron microscopy is to use new instrumentation and methods to extract the maximum amount of information from each electron. This is evident in the increasing popularity of techniques such as 4D-STEM combined with ptychography in materials science, and cryogenic microcrystal electron diffraction in structural biology, where subtle differences in the scattering potential may be both measurable and contain additional insights. Thus, there is increasing interest in electron scattering simulations based on electrostatic potentials obtained from first principles, mainly via density functional theory, which was previously mainly required for holography. In this Review, we discuss the motivation and basis for these developments, survey the pioneering work that has been published thus far, and give our outlook for the future. We argue that a physically better justified ab initio description of the scattering potential is both useful and viable for an increasing number of systems, and we expect such simulations to steadily gain in popularity and importance. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000744190300006 |
Publication Date |
2021-03-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
|
Approved |
Most recent IF: 2.843 |
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| |
Call Number |
UA @ admin @ c:irua:183955 |
Serial |
6850 |
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| Permanent link to this record |
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| |
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Author |
Wang, H.; Cuppens, J.; Biermans, E.; Bals, S.; Fernandez-Ballester, L.; Kvashnina, K.O.; Bras, W.; van Bael, M.J.; Temst, K.; Vantomme, A. |
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Title |
Tuning of the size and the lattice parameter of ion-beam synthesized Pb nanoparticles embedded in Si |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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| |
Volume |
45 |
Issue |
3 |
Pages |
035301-035301,7 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The size and lattice constant evolution of Pb nanoparticles (NPs) synthesized by high fluence implantation in crystalline Si have been studied with a variety of experimental techniques. Results obtained from small-angle x-ray scattering showed that the Pb NPs grow with increasing implantation fluence and annealing duration. The theory of NP growth kinetics can be applied to qualitatively explain the size evolution of the Pb NPs during the implantation and annealing processes. Moreover, the lattice constant of the Pb NPs was evaluated by conventional x-ray diffraction. The lattice dilatation was observed to decrease with increasing size of the Pb NPs. Such lattice constant tuning can be attributed to the pseudomorphism caused by the lattice mismatch between the Pb NPs and the Si matrix. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000299308400008 |
Publication Date |
2011-12-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.588 |
Times cited |
5 |
Open Access |
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| |
Notes |
Fwo; Iap |
Approved |
Most recent IF: 2.588; 2012 IF: 2.528 |
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| |
Call Number |
UA @ lucian @ c:irua:94208 |
Serial |
3754 |
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| Permanent link to this record |
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Author |
Cao, S.; Somsen, C.; Croitoru, M.; Schryvers, D.; Eggeler, G. |
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Title |
Focused ion beam/scanning electron microscopy tomography and conventional transmission electron microscopy assessment of Ni4Ti3 morphology in compression-aged Ni-rich Ni-Ti single crystals |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
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| |
Volume |
62 |
Issue |
6 |
Pages |
399-402 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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| |
Abstract |
The size, morphology and configuration of Ni4Ti3 precipitates in a single-crystal NiTi alloy have been investigated by two-dimensional transmission electron microscopy-based image analysis and three-dimensional reconstruction from slice-and-view images obtained in a focused ion beam/scanning electron microscopy (FIB/SEM) dual-beam system. Average distances between the precipitates measured along the compression direction correlate well between both techniques, while particle shape and configuration data is best obtained from FIB/SEM. Precipitates form pockets of B2 of 0.54 ìm in the compression direction and 1 ìm perpendicular to the compression direction. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
|
Wos |
000275072700020 |
Publication Date |
2009-12-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.747 |
Times cited |
16 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 3.747; 2010 IF: 2.820 |
|
| |
Call Number |
UA @ lucian @ c:irua:79817 |
Serial |
1246 |
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| Permanent link to this record |
| |
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| |
|
Author |
Cao, S.; Pourbabak, S.; Schryvers, D. |
|
| |
Title |
Quantitative 3-D morphologic and distributional study of Ni4Ti3 precipitates in a Ni51Ti49 single crystal alloy |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
|
| |
Volume |
66 |
Issue |
9 |
Pages |
650-653 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The size, shape and distribution of Ni4Ti3 precipitates in Ni51Ti49 single crystals annealed under stress-free and 〈1 1 1〉B2 compressive conditions are studied via focused ion beam/scanning electron microscopy slice-and-view. The precipitates in the stress-free material grow in autocatalytic pockets with larger size, lower number density, flatter shape and larger inter-particle distance than in the compressed material. Nevertheless, a new quantification method called water penetration reveals that, due to the precipitate alignment, martensite can grow more easily in the compressed material perpendicular to the compression direction. |
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| |
Address |
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| |
Corporate Author |
|
Thesis |
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| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
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| |
Language |
|
Wos |
000302425100010 |
Publication Date |
2012-01-30 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.747 |
Times cited |
8 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 3.747; 2012 IF: 2.821 |
|
| |
Call Number |
UA @ lucian @ c:irua:97387 |
Serial |
2743 |
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| Permanent link to this record |
| |
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| |
|
Author |
Zhao, H.; Hu, Z.; Liu, J.; Li, Y.; Wu, M.; Van Tendeloo, G.; Su, B.-L. |
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| |
Title |
Blue-edge slow photons promoting visible-light hydrogen production on gradient ternary 3DOM TiO 2 -Au-CdS photonic crystals |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Nano energy |
Abbreviated Journal |
Nano Energy |
|
| |
Volume |
47 |
Issue |
|
Pages |
266-274 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The slow photon effect, a structural effect of photonic crystal photocatalyst, is very efficient in the enhancement of photocatalytic reactions. However, slow photons in powdered photonic crystal photocatalyst have rarely been discussed because they are usually randomly oriented when the photocatalytic reaction happens in solution under constant stirring. In this work, for the first time we design a gradient ternary TiO2-Au-CdS photonic crystal based on three-dimensionally ordered macroporous (3DOM) TiO2 as skeleton, Au as electron transfer medium and CdS as active material for photocatalytic H2 production under visible-light. As a result, this gradient ternary photocatalyst is favorable to simultaneously enhance light absorption, extend the light responsive region and reduce the recombination rate of the charge carriers. In particular, we found that slow photons at blue-edge exhibit much higher photocatalytic activity than that at red-edge. The photonic crystal photocatalyst with a macropore size of 250 nm exhibits the highest visible-light H2 production rate of 3.50 mmolh⁻¹g⁻¹ due to the slow photon energy at the blue-edge to significantly enhance the incident photons utilization. This work verifies that slow photons at the blue-edge can largely enhance light harvesting and sheds a light on designing the powdered photonic crystal photocatalyst to promote the photocatalytic H2 production via slow photon effect. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
|
Editor |
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|
| |
Language |
|
Wos |
000430057000027 |
Publication Date |
2018-02-27 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2211-2855 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
12.343 |
Times cited |
33 |
Open Access |
OpenAccess |
|
| |
Notes |
B. L. Su acknowledges the Chinese Central Government for an “Expert of the State” position in the Program of the “Thousand Talents”. Y. Li acknowledges Hubei Provincial Department of Education for the “Chutian Scholar” program. This work is financially supported the National KeyR&D Program of China (2016YFA0202602), National Natural Science Foundation of China (U1663225, 51502225), Program for Changjiang Scholars and Innovative Research Team in University (IRT_15R52), Hubei Provincial Natural Science Foundation (2015CFB516), International Science &Technology Cooperation Program of China (2015DFE52870) and the Fundamental Research Funds for the Central Universities (WUT: 2016III029). |
Approved |
Most recent IF: 12.343 |
|
| |
Call Number |
EMAT @ lucian @c:irua:150721 |
Serial |
4924 |
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| Permanent link to this record |
| |
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| |
|
Author |
Abakumov, A.M.; Tsirlin, A.A.; Perez-Mato, J.M.; Petřiček, V.; Rosner, H.; Yang, T.; Greenblatt, M. |
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| |
Title |
Spiral ground state against ferroelectricity in the frustrated magnet BiMnFe2O6 |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
83 |
Issue |
21 |
Pages |
214402-214402,10 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The spiral magnetic structure and underlying spin lattice of BiMnFe2O6 are investigated by low-temperature neutron powder diffraction and density functional theory band structure calculations. In spite of the random distribution of the Mn3+ and Fe3+ cations, this centrosymmetric compound undergoes a transition into an incommensurate antiferromagnetically ordered state below TN≃220 K. The magnetic structure is characterized by the propagation vector k=[0,β,0] with β≃0.14 and the P221211′(0β0)0s0s magnetic superspace symmetry. It comprises antiferromagnetic helixes propagating along the b axis. The magnetic moments lie in the ac plane and rotate about π(1+β)≃204.8-deg angle between the adjacent magnetic atoms along b. The spiral magnetic structure arises from the peculiar frustrated arrangement of exchange couplings in the ab plane. The antiferromagnetic coupling along the c axis cancels the possible electric polarization and prevents ferroelectricity in BiMnFe2O6. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
|
Editor |
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| |
Language |
|
Wos |
000291197400001 |
Publication Date |
2011-06-03 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
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 |
12 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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| |
Call Number |
UA @ lucian @ c:irua:90080 |
Serial |
3107 |
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| Permanent link to this record |
| |
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| |
|
Author |
De Meulenaere, P.; Rodewald, M.; Van Tendeloo, G. |
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| |
Title |
Anisotropic cluster model for the short-range order in Cu1-xPdx-type alloys |
Type |
A1 Journal article |
| |
Year |
1998 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
57 |
Issue |
18 |
Pages |
11132-11140 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The split diffuse maxima around the {110} and {100} positions in the diffraction pattern of short-range-ordered Cu1-xPdx alloys (x=0.10...0.60) are attributed to small atomic clusters, being part of the underlying fee lattice. By analyzing the reciprocal space geometry, our cluster method identifies two prominent cluster types: the tetrahedron of nearest neighbors and a linear three-points cluster along the [110] directions. Since both cluster types contain different information on the same nearest-neighbor correlations, local anisotropy has to be assumed. It is shown that the three interatomic pair interactions within these basic clusters are sufficient to generate the spot splitting in the diffraction pattern. A ground-state analysis with these interactions reproduces the results of the anisotropic next-nearest-neighbor Ising model. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
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| |
Language |
|
Wos |
000073585200026 |
Publication Date |
2002-07-27 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
1 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 3.836; 1998 IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:25678 |
Serial |
125 |
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| Permanent link to this record |
| |
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| |
|
Author |
Abakumov, A.M.; d' Hondt, H.; Rossell, M.D.; Tsirlin, A.A.; Gutnikova, O.; Filimonov, D.S.; Schnelle, W.; Rosner, H.; Hadermann, J.; Van Tendeloo, G.; Antipov, E.V. |
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| |
Title |
Coupled anion and cation ordering in Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficientperovskites |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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| |
Volume |
183 |
Issue |
12 |
Pages |
2845-2854 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficient perovskites were prepared using a solid-state reaction in evacuated sealed silica tubes. Transmission electron microscopy and 57Fe Mössbauer spectroscopy evidenced a complete A-cations and oxygen vacancies ordering. The structure model was further refined by ab initio structure relaxation, based on density functional theory calculations. The compounds crystallize in a tetragonal a≈2√2ap≈11.3 Å, с≈4сp≈16 Å unit cell (ap: parameter of the perovskite subcell) with the P42/mnm space group. Oxygen vacancies reside in the (FeO5/4□3/4) layers, comprising corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids, which are sandwiched between the layers of the FeO6 octahedra. Smaller R atoms occupy the 9-fold coordinated position, whereas the 10-fold coordinated positions are occupied by larger Sr atoms. The Fe sublattice is ordered aniferromagnetically up to at least 500 K, while the rare-earth sublattice remains disordered down to 2 K. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
London |
Editor |
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| |
Language |
|
Wos |
000285431100014 |
Publication Date |
2010-10-02 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.299 |
Times cited |
8 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
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| |
Call Number |
UA @ lucian @ c:irua:88071 |
Serial |
533 |
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| Permanent link to this record |
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| |
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Author |
Tian, H.; Schryvers, D.; Liu, D.; Jiang, Q.; van Humbeeck, J. |
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| |
Title |
Stability of Ni in nitinol oxide surfaces |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Acta biomaterialia |
Abbreviated Journal |
Acta Biomater |
|
| |
Volume |
7 |
Issue |
2 |
Pages |
892-899 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The stability of Ni in titanium oxide surface layers on nitinol wires known to release certain amounts of Ni was investigated by first principles density functional theory and transmission electron microscopy. The oxides were identified as a combination of TiO and TiO2 depending on the thickness of the layer. The calculations indicate that free Ni atoms can exist in TiO at ambient temperature while Ni particles form in TiO2, which was confirmed by the transmission electron microscopy observations. The results are discussed with respect to surface stability and Ni release due to free Ni atoms and Ni particles. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
S.l. |
Editor |
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| |
Language |
|
Wos |
000286707700047 |
Publication Date |
2010-09-17 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-7061; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
6.319 |
Times cited |
39 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 6.319; 2011 IF: 4.865 |
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| |
Call Number |
UA @ lucian @ c:irua:85998 |
Serial |
3128 |
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| Permanent link to this record |
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| |
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Author |
Wang, J.; Zhang, K.; Kavak, S.; Bals, S.; Meynen, V. |
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| |
Title |
Modifying the Stöber Process: Is the Organic Solvent Indispensable? |
Type |
A1 Journal Article |
| |
Year |
2022 |
Publication |
Chemistry-A European Journal |
Abbreviated Journal |
Chem-Eur J |
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| |
Volume |
|
Issue |
|
Pages |
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| |
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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| |
Abstract |
The Stöber method is one of the most important and fundamental processes for the synthesis of inorganic (nano)materials but has the drawback of using a large amount of organic solvent. Herein, ethanol was used as an example to explore if the organic solvent in a typical Stöber method can be omitted. It was found that ethanol increases the particle size of the obtained silica spheres and aids the formation of uniform silica particles rather than forming a gel. Nevertheless, the results indicated that an organic solvent in the initial synthesis mixture is not indispensable. An initially immiscible synthesis method was discovered, which can replace the organic solvent-based Stöber method to successfully synthesize silica particles with the same size ranges as the original Stöber process without addition of organic solvents. Moreover, this process can be of further value for the extension to synthesis processes of other materials based on the Stöber process. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
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Editor |
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| |
Language |
|
Wos |
000898283500001 |
Publication Date |
2022-12-14 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0947-6539 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.3 |
Times cited |
3 |
Open Access |
OpenAccess |
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| |
Notes |
The authors are grateful to Alexander Vansant and Dr. Steven Mullens of VITO for their contributions to the DLS measurements in this paper. J.W acknowledges the State Scholarship funded by the China Scholarship Council (201806060123). K.Z acknowledges the EASiCHEM project funded by the Flemish Strategic Basic Research Program of the Catalisti cluster and Flanders Innovation & Entrepreneurship (HBC.2018.0484). S.K acknowledges the Flemish Fund for Scientific Research (FWO Flanders) through a PhD research grant (1181122N). |
Approved |
Most recent IF: 4.3 |
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| |
Call Number |
EMAT @ emat @c:irua:191646 |
Serial |
7233 |
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| Permanent link to this record |
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| |
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Author |
Milovanović, S.P.; Andelkovic, M.; Covaci, L.; Peeters, F.M. |
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| |
Title |
Band flattening in buckled monolayer graphene |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
102 |
Issue |
24 |
Pages |
245427 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
| |
Abstract |
The strain fields of periodically buckled graphene induce a periodic pseudomagnetic field (PMF) that modifies the electronic band structure. From the geometry, amplitude, and period of the periodic pseudomagnetic field, we determine the necessary conditions to access the regime of correlated phases by examining the band flattening. As compared to twisted bilayer graphene the proposed system has the advantages that (1) only a single layer of graphene is needed, (2) one is not limited to hexagonal superlattices, and (3) narrower flat bandwidth and larger separation between flat bands can be induced. We, therefore, propose that periodically strained graphene single layers can become a platform for the exploration of exotic many-body phases. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
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Editor |
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| |
Language |
|
Wos |
000602844600007 |
Publication Date |
2020-12-28 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.7 |
Times cited |
11 |
Open Access |
OpenAccess |
|
| |
Notes |
; S.P.M. is supported by the Flemish Science Foundation (FWO). We thank E. Y. Andrei, Y. Jiang, and J. Mao for fruitful discussions. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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| |
Call Number |
UA @ admin @ c:irua:175021 |
Serial |
6684 |
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| Permanent link to this record |
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| |
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Author |
Cooper, D.; Le Royer, C.; Béché, A.; Rouvière, J.-L. |
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| |
Title |
Strain mapping for the silicon-on-insulator generation of semiconductor devices by high-angle annular dark field scanning electron transmission microscopy |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
|
| |
Volume |
100 |
Issue |
|
Pages |
233121 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The strain in pMOS p-type metal-oxide-semiconductor devicesgrown on silicon-on-insulator substrates has been measured by using the geometrical phase analysis of high angle annular dark field scanning electron microscopy. We show that by using the latest generations of electron microscopes, the strain can now be quantitatively measured with a large field of view, a spatial resolution as low as 1 nm with a sensitivity as good as 0.15%. This technique is extremely flexible, provides both structural and strain information, and can be applied to all types of nanoscale materials both quickly and easily. |
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| |
Address |
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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 |
|
Wos |
|
Publication Date |
2012-06-08 |
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| |
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 |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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| |
Call Number |
UA @ lucian @ c:irua:136432 |
Serial |
4509 |
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| Permanent link to this record |
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| |
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Author |
Penders, A.; Konstantinovic, M.J.; Van Renterghem, W.; Bosch, R.W.; Schryvers, D. |
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| |
Title |
TEM investigation of SCC crack tips in high Si stainless steel tapered specimens |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Corrosion Engineering Science And Technology |
Abbreviated Journal |
Corros Eng Sci Techn |
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| |
Volume |
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Issue |
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Pages |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The stress corrosion cracking (SCC) mechanism is investigated in high Si duplex stainless steel in a simulated PWR environment based on TEM analysis of FIB-extracted SCC crack tips. The microstructural investigation in the near vicinity of SCC crack tips illustrates a strain-rate dependence in SCC mechanisms. Detailed analysis of the crack tip morphology, that includes crack tip oxidation and surrounding deformation field, indicates the existence of an interplay between corrosion- and deformation-driven failure as a function of the strain rate. Slow strain-rate crack tips exhibit a narrow cleavage failure which can be linked to the film-induced failure mechanism, while rounded shaped crack tips for faster strain rates could be related to the strain-induced failure. As a result, two nominal strain-rate-dependent failure regimes dominated either by corrosion or deformation-driven cracking mechanisms can be distinguished. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
|
Editor |
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| |
Language |
|
Wos |
000695956400001 |
Publication Date |
2021-09-14 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1478-422x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
0.879 |
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
Most recent IF: 0.879 |
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| |
Call Number |
UA @ admin @ c:irua:181533 |
Serial |
6892 |
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| Permanent link to this record |
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| |
|
Author |
Du, K. |
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| |
Title |
In situ TEM study on the manipulation of ferroelectrics |
Type |
Doctoral thesis |
| |
Year |
2021 |
Publication |
|
Abbreviated Journal |
|
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| |
Volume |
|
Issue |
|
Pages |
91 p. |
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| |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The strong correlated oxide systems attract a lot of attentions of scientists recently, the coexistence and interplay between various degrees of freedom, such as charge, spin and orbital, has been demonstrated to induce some fancy physical properties and phenomenon, including metal-insulator transition, high temperature superconductivity, colossal magnetoresistance. As a part of the strong correlated oxide systems, the ferroelectrics is abundant in both physical properties and application. First, if the electric dipole continuously rotating around a stable core then a topological structure is produced. If people could manipulate the topological structure and simultaneously observe the structure evolution, with external field applied on the topological structure, then it is very likely for such kind of ferroelectrics to be the next generation of storage, for it is reported to need low power input and produce high density of storage. In the other hand, in solids, charge polarity can one-to-one correspond to spin polarity phenomenologically, such as ferroelectricity and ferromagnetism, antiferroelectricity and antiferromagnetism, but ferrielectricity and ferrimagnetism kept telling a disparate story in microscopic level. The claimed “ferrielectrics” in existing research is equivalent to ferroelectric ones, thus the findings of such a real irreducible solids would complete the last piece of the ferroelectrics family. While solving the above two questions remain challengeable: the size of topological structure is small (typically below 10 nm), general characterization methods are insufficient for such high demand on space resolution, not to mention manipulating and observing its dynamic behavior at an atomic level. Here, employing the spherical aberration corrected electron microscope, we applied external field (heating and bias) on ferroelectrics. Combined with high-end characterization methods including the high-angle annular dark field (HAADF-STEM) image, Electron Energy Loss Spectroscopy (EELS) and integrated differential phase contrast (iDPC), the dynamic evolution of ferroelectrics are observed and analyzed. The main findings of this paper could be concluded as listed here: (1) PbTiO3(001)// SrTiO3(001) is grown on DyScO3 and SrRuO3 by pusled laser deposition, the atomical EDS mapping results reveal that the interface between PTO and STO is atomically sharp. Increasing the thickness of PTO from 1 uc to 21 uc, the topological structure wihtin PTO layer would transform from a/c domain to wave, vortex and finally flux closure domain. The geometric phase analysis results (GPA) reveal that above topological structures are corresponding to various strain. (2) Combined with in-situ biasing holder, the electric bias was applied on polar vortex, and it evolved from vortex (0 V) to polar wave (2 V) and finally polar down (5 V). EELS analysis was performed and we find that negative charge is gathered at vortex core, which turns the Ti4+ to Ti3+ there. The oxygen vacancy at negative polarization surface and the negative charge at the positive polarization surface realized the polarization screening of polar down domain. (3) Through the atomic inspection and analysis on lattice structure of BaFe2Se3, the near ladders within single unit are found to be different in degree of tetramerization, thus leading to a residual polarization along the a-axis. The further in-situ heating and biasing experiment was conducted on BaFe2Se3, and the strong and weak ladders are proved to be independent for their behavior under external field. This findings distinguishes ferrielectrics from ferroelectrics in solids. |
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UA library record |
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Most recent IF: NA |
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UA @ admin @ c:irua:179310 |
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6842 |
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