| |
Records |
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Author |
Herzog, M.J.; Gauquelin, N.; Esken, D.; Verbeeck, J.; Janek, J. |
| |
Title |
Facile dry coating method of high-nickel cathode material by nanostructured fumed alumina (Al2O3) improving the performance of lithium-ion batteries |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Energy technology |
Abbreviated Journal |
|
| |
Volume |
9 |
Issue |
4 |
Pages |
2100028 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Surface coating is a crucial method to mitigate the aging problem of high-Ni cathode active materials (CAMs). By avoiding the direct contact of the CAM and the electrolyte, side reactions are hindered. Commonly used techniques like wet or ALD coating are time consuming and costly. Therefore, a more cost-effective coating technique is desirable. Herein, a facile and fast dry powder coating process for CAMs with nanostructured fumed metal oxides are reported. As the model case, the coating of high-Ni NMC (LiNi0.7Mn0.15Co0.15O2) by nanostructured fumed Al2O3 is investigated. A high coverage of the CAM surface with an almost continuous coating layer is achieved, still showing some porosity. Electrochemical evaluation shows a significant increase in capacity retention, cycle life and rate performance of the coated NMC material. The coating layer protects the surface of the CAM successfully and prevents side reactions, resulting in reduced solid electrolyte interface (SEI) formation and charge transfer impedance during cycling. A mechanism on how the coating layer enhances the cycling performance is hypothesized. The stable coating layer effectively prevents crack formation and particle disintegration of the NMC. In depth analysis indicates partial formation of LixAl2O3/LiAlO2 in the coating layer during cycling, enhancing lithium ion diffusivity and thus, also the rate performance. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000621000700001 |
Publication Date |
2021-01-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
| |
ISSN |
2194-4296; 2194-4288 |
ISBN  |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
25 |
Open Access |
OpenAccess |
| |
Notes |
The authors would like to thank Erik Peldszus and Steve Rienecker for the support with scanning electron microscopy and X-ray photoelectron spectroscopy analysis. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government. N.G. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. Funding from the Flemish Research Fund (FWO) project G0F1320N is acknowledged.; Open access funding enabled and organized by Projekt DEAL. |
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ admin @ c:irua:176670 |
Serial |
6724 |
| Permanent link to this record |
| |
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| |
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Author |
Sun, M.-H.; Zhou, J.; Hu, Z.-Y.; Chen, L.-H.; Li, L.-Y.; Wang, Y.-D.; Xie, Z.-K.; Turner, S.; Van Tendeloo, G.; Hasan, T.; Su, B.-L. |
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Title |
Hierarchical zeolite single-crystal reactor for excellent catalytic efficiency |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Matter |
Abbreviated Journal |
|
| |
Volume |
3 |
Issue |
4 |
Pages |
1226-1245 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
As a size- and shape-selective catalyst, zeolites are widely used in petroleum and fine-chemicals processing. However, their small micropores severely hinder molecular diffusion and are sensitive to coke formation. Hierarchically porous zeolite single crystals with fully interconnected, ordered, and tunable multimodal porosity at macro-, meso-, and microlength scale, like in leaves, offer the ideal solution. However, their synthesis remains highly challenging. Here, we report a versatile confined zeolite crystallization process to achieve these superior properties. Such zeolite single crystals lead to significantly improved mass transport properties by shortening the diffusion length while maintaining shape-selective properties, endowing them with a high efficiency of zeolite crystals, enhanced catalytic activities and lifetime, highly reduced coke formation, and reduced deactivation rate in bulky-molecule reactions and methanol-to-olefins process. Their industrial utilization can lead to the design of innovative and intensified reactors and processes with highly enhanced efficiency and minimum energy consumption. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000581132600021 |
Publication Date |
2020-08-12 |
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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 |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
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Approved |
Most recent IF: NA |
| |
Call Number |
UA @ admin @ c:irua:174329 |
Serial |
6727 |
| Permanent link to this record |
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| |
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Author |
Bahrami, F.; Hammad, M.; Fivel, M.; Huet, B.; D'Haese, C.; Ding, L.; Nysten, B.; Idrissi, H.; Raskin, J.P.; Pardoen, T. |
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Title |
Single layer graphene controlled surface and bulk indentation plasticity in copper |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
International Journal Of Plasticity |
Abbreviated Journal |
Int J Plasticity |
| |
Volume |
138 |
Issue |
|
Pages |
102936 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The impact of graphene reinforcement on the mechanical properties of metals has been a subject of intense investigation over the last decade in surface applications to mitigate the impact of tribological loadings or for strengthening purposes when dispersed into a bulk material. Here, the effect on the plastic indentation response of a single graphene layer grown on copper is analyzed for two configurations: one with graphene at the surface, the other with graphene sandwiched under a 100 nm thick copper cap layer. Nanoindentation under both displacement and load control conditions show both earlier and shorter pop-in excursions compared to systems without graphene. Atomic force microscopy reveals much smoother pile-ups with no slip traces in the presence of a surface graphene layer. The configuration with the intercalated graphene layer appears as an ideal elementary system to address bulk hardening mechanisms by indentation testing. Transmission electron microscopy (TEM) cross-sections below indents show more diffuse and homogeneous dislocation activity in the presence of graphene. 3D dislocation dynamics simulations allow unraveling of the origin of these 3D complex phenomena and prove that the collective dislocation mechanisms are dominantly controlled by the strong back stress caused by the graphene barrier. These results provide a quantitative understanding of the impact of graphene on dislocation mechanisms for both surface and bulk applications, but with an impact that is not as large as anticipated from other studies or general literature claims. |
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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 |
000623869800001 |
Publication Date |
2021-01-18 |
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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 |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0749-6419 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.702 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 5.702 |
| |
Call Number |
UA @ admin @ c:irua:176729 |
Serial |
6735 |
| Permanent link to this record |
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Author |
Chen, B.; Gauquelin, N.; Green, R.J.; Lee, J.H.; Piamonteze, C.; Spreitzer, M.; Jannis, D.; Verbeeck, J.; Bibes, M.; Huijben, M.; Rijnders, G.; Koster, G. |
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Title |
Spatially controlled octahedral rotations and metal-insulator transitions in nickelate superlattices |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
| |
Volume |
21 |
Issue |
3 |
Pages |
1295-1302 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The properties of correlated oxides can be manipulated by forming short-period superlattices since the layer thicknesses are comparable with the typical length scales of the involved correlations and interface effects. Herein, we studied the metal-insulator transitions (MITs) in tetragonal NdNiO3/SrTiO3 superlattices by controlling the NdNiO3 layer thickness, n in the unit cell, spanning the length scale of the interfacial octahedral coupling. Scanning transmission electron microscopy reveals a crossover from a modulated octahedral superstructure at n = 8 to a uniform nontilt pattern at n = 4, accompanied by a drastically weakened insulating ground state. Upon further reducing n the predominant dimensionality effect continuously raises the MIT temperature, while leaving the antiferromagnetic transition temperature unaltered down to n = 2. Remarkably, the MIT can be enhanced by imposing a sufficiently large strain even with strongly suppressed octahedral rotations. Our results demonstrate the relevance for the control of oxide functionalities at reduced dimensions. |
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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 |
000619638600014 |
Publication Date |
2021-01-20 |
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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 |
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Edition |
|
| |
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
12.712 |
Times cited |
19 |
Open Access |
OpenAccess |
| |
Notes |
This work is supported by the international M-ERA.NET project SIOX (project 4288). J.V. and N.G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. D.J. acknowledges funding from FWO Project G093417N from the Flemish fund for scientific research. M.S. acknowledges funding from Slovenian Research Agency (Grants J2-9237 and P2-0091). R.J.G. acknowledges funding from the Natural Sciences and Engineering Research Council of Canada (NSERC). Part of the research described in this paper was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation (CFI), NSERC, the National Research Council (NRC), the Canadian Institutes of Health Research (CIHR), the Government of Saskatchewan, and the University of Saskatchewan. This work received support from the ERC CoG MINT (No. 615759) and from a PHC Van Gogh grant. M.B. thanks the French Academy of Science and the Royal Netherlands Academy of Arts and Sciences for supporting his stays in The Netherlands. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 823717 -ESTEEM3. |
Approved |
Most recent IF: 12.712 |
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Call Number |
UA @ admin @ c:irua:176753 |
Serial |
6736 |
| Permanent link to this record |
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Author |
Hendrickx, M.; Tang, Y.; Hunter, E.C.; Battle, P.D.; Hadermann, J. |
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Title |
Structural and magnetic properties of the perovskites A₂LaFe₂SbO₉ (A = Ca, Sr, Ba) |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of Solid State Chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
295 |
Issue |
|
Pages |
121914 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Polycrystalline samples of A(2)LaFe(2)SbO(9) (A = Ca, Sr, Ba) perovskites appeared monophasic to X-ray or neutron powder diffraction but a single-crystal study utilising transmission electron microscopy revealed a greater level of complexity. Although local charge balance is maintained, compositional and structural variations are present among and within the submicron-sized crystals. Despite the inhomogeneity, A = Ca is monophasic with a partially-ordered distribution of Fe3+ and Sb5+ cations across two crystallographically-distinct octahedral sites, i.e. Ca2La(Fe1.25Sb0.25)(2d) (Fe0.75Sb0.75)(2c)O-9. For A = Sr or Ba, the inhomogeneities result in differences in the filling patterns of the octahedra and the ordering of the B cations. Particles of A = Sr contain a phase (Fe:Sb similar to 2:1) without B cation ordering and one (Fe:Sb similar to 1:1) with B cation ordering. Monophasic A = Ba lacks long-range cation order although ordered nanodomains are present within the disordered phase. The temperature dependence of the magnetic properties of each sample is discussed. |
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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 |
000615711800013 |
Publication Date |
2020-12-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0022-4596 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.299 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
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Approved |
Most recent IF: 2.299 |
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Call Number |
UA @ admin @ c:irua:176663 |
Serial |
6739 |
| Permanent link to this record |
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Author |
Bafekry, A.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Shojaei, F.; Feghhi, S.A.H.; Ghergherehchi, M.; Gogova, D. |
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Title |
Two-dimensional carbon nitride C₆N nanosheet with egg-comb-like structure and electronic properties of a semimetal |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
| |
Volume |
32 |
Issue |
21 |
Pages |
215702 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
In this study, the structural, electronic and optical properties of theoretically predicted C6N monolayer structure are investigated by means of Density Functional Theory-based First-Principles Calculations. Phonon band dispersion calculations and molecular dynamics simulations reveal the dynamical and thermal stability of the C6N single-layer structure. We found out that the C6N monolayer has large negative in-plane Poisson's ratios along both X and Y direction and the both values are almost four times that of the famous-pentagraphene. The electronic structure shows that C6N monolayer is a semi-metal and has a Dirac-point in the BZ. The optical analysis using the random phase approximation method constructed over HSE06 illustrates that the first peak of absorption coefficient of the C6N monolayer along all polarizations is located in the IR range of spectrum, while the second absorption peak occurs in the visible range, which suggests its potential applications in optical and electronic devices. Interestingly, optically anisotropic character of this system is highly desirable for the design of polarization-sensitive photodetectors. Thermoelectric properties such as Seebeck coefficient, electrical conductivity, electronic thermal conductivity and power factor are investigated as a function of carrier doping at temperatures 300, 400, and 500 K. In general, we predict that the C6N monolayer could be a new platform for study of novel physical properties in two-dimensional semi-metal materials, which may provide new opportunities to realize high-speed low-dissipation devices. |
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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 |
000624531500001 |
Publication Date |
2020-12-18 |
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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 |
0957-4484 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.44 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.44 |
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Call Number |
UA @ admin @ c:irua:176648 |
Serial |
6740 |
| Permanent link to this record |
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Author |
Chen, X.; Li, L.; Peeters, F.M.; Sanyal, B. |
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Title |
Two-dimensional oxygen functionalized honeycomb and zigzag dumbbell silicene with robust Dirac cones |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
New Journal Of Physics |
Abbreviated Journal |
New J Phys |
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Volume |
23 |
Issue |
2 |
Pages |
023007 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Dumbbell-like structures are recently found to be energetically favored in group IV two-dimensional (2D) materials, exhibiting rich physics and many interesting properties. In this paper, using first-principles calculations, we have investigated the oxidized form of the hexagonal honeycomb (ODB-h) and zigzag dumbbell silicene (ODB-z). We confirm that both oxidization processes are energetically favorable, and their phonon spectra further demonstrate the dynamic stability. Contrary to the pristine dumbbell silicene structures (PDB-h and PDB-z silicene), these oxidized products ODB-h and ODB-z silicene are both semimetals with Dirac cones at the Fermi level. The Dirac cones of ODB-h and ODB-z silicene are at the K point and between Y and Gamma points respectively, possessing high Fermi velocities of 3.1 x 10(5) m s(-1) (ODB-h) and 2.9-3.4 x 10(5) m s(-1) (ODB-z). The origin of the Dirac cones is further explained by tight-binding models. The semimetallic properties of ODB-h and ODB-z are sensitive to compression due to the self-absorption effect, but quite robust against the tensile strain. These outstanding properties make oxidized dumbbell silicene a promising material for quantum computing and high-speed electronic devices. |
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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 |
000616114900001 |
Publication Date |
2021-01-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1367-2630 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.786 |
Times cited |
2 |
Open Access |
OpenAccess |
| |
Notes |
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Approved |
Most recent IF: 3.786 |
| |
Call Number |
UA @ admin @ c:irua:176575 |
Serial |
6741 |
| Permanent link to this record |
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Author |
Kovács, A.; Billen, P.; Cornet, I.; Wijnants, M.; Neyts, E.C. |
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Title |
Modeling the physicochemical properties of natural deep eutectic solvents : a review |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Chemsuschem |
Abbreviated Journal |
Chemsuschem |
| |
Volume |
13 |
Issue |
15 |
Pages |
3789-3804 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Biochemical Wastewater Valorization & Engineering (BioWaVE) |
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Abstract |
Natural deep eutectic solvents (NADES) are mixtures of naturally derived compounds with a significantly decreased melting point due to the specific interactions among the constituents. NADES have benign properties (low volatility, flammability, toxicity, cost) and tailorable physicochemical properties (by altering the type and molar ratio of constituents), hence they are often considered as a green alternative to common organic solvents. Modeling the relation between their composition and properties is crucial though, both for understanding and predicting their behavior. Several efforts were done to this end, yet this review aims at structuring the present knowledge as an outline for future research. First, we reviewed the key properties of NADES and relate them to their structure based on the available experimental data. Second, we reviewed available modeling methods applicable to NADES. At the molecular level, density functional theory and molecular dynamics allow interpreting density differences and vibrational spectra, and computation of interaction energies. Additionally, properties at the level of the bulk media can be explained and predicted by semi-empirical methods based on ab initio methods (COSMO-RS) and equation of state models (PC-SAFT). Finally, methods based on large datasets are discussed; models based on group contribution methods and machine learning. A combination of bulk media and dataset modeling allows qualitative prediction and interpretation of phase equilibria properties on the one hand, and quantitative prediction of melting point, density, viscosity, surface tension and refractive indices on the other hand. In our view, multiscale modeling, combining the molecular and macroscale methods, will strongly enhance the predictability of NADES properties and their interaction with solutes, yielding truly tailorable solvents to accommodate (bio)chemical reactions. |
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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 |
000541499100001 |
Publication Date |
2020-05-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1864-5631 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
8.4 |
Times cited |
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Open Access |
|
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Notes |
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Approved |
Most recent IF: 8.4; 2020 IF: 7.226 |
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Call Number |
UA @ admin @ c:irua:168851 |
Serial |
6770 |
| Permanent link to this record |
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Author |
Kaliyappan, P.; Paulus, A.; D’Haen, J.; Samyn, P.; Uytdenhouwen, Y.; Hafezkhiabani, N.; Bogaerts, A.; Meynen, V.; Elen, K.; Hardy, A.; Van Bael, M.K. |
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Title |
Probing the impact of material properties of core-shell SiO₂@TiO₂ spheres on the plasma-catalytic CO₂ dissociation using a packed bed DBD plasma reactor |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of Co2 Utilization |
Abbreviated Journal |
J Co2 Util |
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Volume |
46 |
Issue |
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Pages |
101468 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
Plasma catalysis, a promising technology for conversion of CO2 into value-added chemicals near room temperature, is gaining increasing interest. A dielectric barrier discharge (DBD) plasma has attracted attention due to its simple design and operation at near ambient conditions, ease to implement catalysts in the plasma zone and upscaling ability to industrial applications. To improve its main drawbacks, being relatively low conversion and energy efficiency, a packing material is used in the plasma discharge zone of the reactor, sometimes decorated by a catalytic material. Nevertheless, the extent to which different properties of the packing material influence plasma performance is still largely unexplored and unknown. In this study, the particular effect of synthesis induced differences in the morphology of a TiO2 shell covering a SiO2 core packing material on the plasma conversion of CO2 is studied. TiO2 has been successfully deposited around 1.6–1.8 mm sized SiO2 spheres by means of spray coating, starting from aqueous citratoperoxotitanate(IV) precursors. Parameters such as concentration of the Ti(IV) precursor solutions and addition of a binder were found to affect the shells’ properties and surface morphology and to have a major impact on the CO2 conversion in a packed bed DBD plasma reactor. Core-shell SiO2@TiO2 obtained from 0.25 M citratoperoxotitante(IV) precursors with the addition of a LUDOX binder showed the highest CO2 conversion 37.7% (at a space time of 70 s corresponding to an energy efficiency of 2%) and the highest energy efficiency of 4.8% (at a space time of 2.5 s corresponding to a conversion of 3%). |
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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 |
000634280300004 |
Publication Date |
2021-02-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
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| |
ISSN |
2212-9820 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.292 |
Times cited |
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Open Access |
OpenAccess |
| |
Notes |
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Approved |
Most recent IF: 4.292 |
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Call Number |
UA @ admin @ c:irua:175958 |
Serial |
6773 |
| Permanent link to this record |
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Author |
Vishwakarma, M.; Kumar, M.; Hendrickx, M.; Hadermann, J.; Singh, A.P.; Batra, Y.; Mehta, B.R. |
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Title |
Enhancing the hydrogen evolution properties of kesterite absorber by Si-doping in the surface of CZTS thin film |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
| |
Volume |
|
Issue |
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Pages |
2002124 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
In this work, the effects of Si-doping in Cu2ZnSnS4 are examined computationally and experimentally. The density functional theory calculations show that an increasing concentration of Si (from x = 0 to x = 1) yields a band gap rise due to shifting of the conduction band minimum towards higher energy states in the Cu2Zn(Sn1-xSix)S-4. CZTSiS thin film prepared by co-sputtering process shows Cu2Zn(Sn1-xSix)S-4 (Si-rich) and Cu2ZnSnS4 (S-rich) kesterite phases on the surface and in the bulk of the sample, respectively. A significant change in surface electronic properties is observed in CZTSiS thin film. Si-doping in CZTS inverts the band bending at grain-boundaries from downward to upward and the Fermi level of CZTSiS shifts upward. Further, the coating of the CdS and ZnO layer improves the photocurrent to approximate to 5.57 mA cm(-2) at -0.41 V-RHE in the CZTSiS/CdS/ZnO sample, which is 2.39 times higher than that of pure CZTS. The flat band potential increases from CZTS approximate to 0.43 V-RHE to CZTSiS/CdS/ZnO approximate to 1.31 V-RHE indicating the faster carrier separation process at the electrode-electrolyte interface in the latter sample. CdS/ZnO layers over CZTSiS significantly reduce the charge transfer resistance at the semiconductor-electrolyte interface. |
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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 |
|
| |
Language |
|
Wos |
000635804900001 |
Publication Date |
2021-04-02 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.279 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 4.279 |
| |
Call Number |
UA @ admin @ c:irua:177688 |
Serial |
6780 |
| Permanent link to this record |
| |
|
| |
|
Author |
Do, M.T.; Gauquelin, N.; Nguyen, M.D.; Blom, F.; Verbeeck, J.; Koster, G.; Houwman, E.P.; Rijnders, G. |
| |
Title |
Interface degradation and field screening mechanism behind bipolar-cycling fatigue in ferroelectric capacitors |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Apl Materials |
Abbreviated Journal |
Apl Mater |
| |
Volume |
9 |
Issue |
2 |
Pages |
021113 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Polarization fatigue, i.e., the loss of polarization of ferroelectric capacitors upon field cycling, has been widely discussed as an interface related effect. However, mechanism(s) behind the development of fatigue have not been fully identified. Here, we study the fatigue mechanisms in Pt/PbZr0.52Ti0.48O3/SrRuO3 (Pt/PZT/SRO) capacitors in which all layers are fabricated by pulsed laser deposition without breaking the vacuum. With scanning transmission electron microscopy, we observed that in the fatigued capacitor, the Pt/PZT interface becomes structurally degraded, forming a 5 nm-10 nm thick non-ferroelectric layer of crystalline ZrO2 and diffused Pt grains. We then found that the fatigued capacitors can regain the full initial polarization switching if the externally applied field is increased to at least 10 times the switching field of the pristine capacitor. These findings suggest that polarization fatigue is driven by a two-step mechanism. First, the transient depolarization field that repeatedly appears during the domain switching under field cycling causes decomposition of the metal/ferroelectric interface, resulting in a non-ferroelectric degraded layer. Second, this interfacial non-ferroelectric layer screens the external applied field causing an increase in the coercive field beyond the usually applied maximum field and consequently suppresses the polarization switching in the cycled capacitor. Our work clearly confirms the key role of the electrode/ferroelectric interface in the endurance of ferroelectric-based devices. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000630052100006 |
Publication Date |
2021-02-09 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2166-532x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.335 |
Times cited |
5 |
Open Access |
OpenAccess |
| |
Notes |
This work was supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek through Grant No. F62.3.15559. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government. N.G. and J.V. acknowledge funding from the GOA project “Solarpaint” of the University of Antwerp. This work has also received funding from the European Union's Horizon 2020 research and innovation program under Grant No. 823717-ESTEEM3. We acknowledge D. Chezganov for his useful insights. |
Approved |
Most recent IF: 4.335 |
| |
Call Number |
UA @ admin @ c:irua:177663 |
Serial |
6783 |
| Permanent link to this record |
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|
Author |
Akamine, H.; Mitsuhara, M.; Nishida, M.; Samaee, V.; Schryvers, D.; Tsukamoto, G.; Kunieda, T.; Fujii, H. |
| |
Title |
Precipitation behaviors in Ti-2.3 Wt Pct Cu alloy during isothermal and two-step aging |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Metallurgical And Materials Transactions A-Physical Metallurgy And Materials Science |
Abbreviated Journal |
Metall Mater Trans A |
| |
Volume |
52 |
Issue |
|
Pages |
2760-2772 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Time evolution of precipitates related to age-hardening in Ti-2.3 wt pct Cu alloys was investigated by electron microscopy. In isothermal aging at 723 K, the hardness increases continuously owing to precipitation strengthening, whereas in two-step aging where the aging temperature is switched from 673 K to 873 K after 100 hours, the hardness is found to drastically drop after the aging temperature switches. In isothermal aging, metastable and stable precipitates are independently nucleated, whereas characteristic V-shaped clusters of precipitates are observed during the two-step aging. It is revealed by atomic-scale observations that the V-shaped clusters are composed of metastable and stable precipitates and each type of precipitate has a different orientation relationship with the alpha phase: (10 (3) over bar)//(0001)(alpha) and [0 (1) over bar0]//respectively. The drop in hardness during two-step aging can be explained by a synergistic effect of decreased precipitation strengthening and solid solution strengthening. (C) The Minerals, Metals & Materials Society and ASM International 2021 |
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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 |
000644823000001 |
Publication Date |
2021-04-27 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1073-5623 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| |
Impact Factor |
1.874 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 1.874 |
| |
Call Number |
UA @ admin @ c:irua:178222 |
Serial |
6786 |
| Permanent link to this record |
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|
| |
|
Author |
Fu, Y.; Ding, L.; Singleton, M.L.; Idrissi, H.; Hermans, S. |
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Title |
Synergistic effects altering reaction pathways : the case of glucose hydrogenation over Fe-Ni catalysts |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Applied Catalysis B-Environmental |
Abbreviated Journal |
Appl Catal B-Environ |
| |
Volume |
288 |
Issue |
|
Pages |
119997 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Carbon black (CB) supported Ni, Fe, or Fe-Ni alloy catalysts were synthesized by sol-gel to elucidate the reaction pathways over each catalyst, as well as synergistic effects in glucose to sorbitol hydrogenation. The bimetallic materials presented small and alloyed nanoparticles that were richer in reduced metallic sites at the surface than their monometallic counterparts. Glucose isomerization to fructose was favoured over Fe/CB, while glucose hydrogenation to sorbitol is the dominating pathway over Ni/CB catalyst. By contrast, sorbitol production was promoted and undesired isomerization was suppressed when Fe and Ni formed a nanoalloy. In addition, the alloy catalyst presented better stability than the corresponding monometallic catalyst. A comparison with a mechanical mixture of Fe/CB and Ni/CB monometallic catalysts demonstrated the synergy at the nanoscale in the alloy. By comparing different Fe:Ni ratios, the 1:1 formulation was identified as the best compromise to achieve a high activity while maintaining high sorbitol selectivity. |
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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 |
000632996500002 |
Publication Date |
2021-02-17 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0926-3373 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
9.446 |
Times cited |
|
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 9.446 |
| |
Call Number |
UA @ admin @ c:irua:177621 |
Serial |
6789 |
| Permanent link to this record |
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Author |
Bhaskar, G.; Gvozdetskyi, V.; Batuk, M.; Wiaderek, K.M.; Sun, Y.; Wang, R.; Zhang, C.; Carnahan, S.L.; Wu, X.; Ribeiro, R.A.; Bud'ko, S.L.; Canfield, P.C.; Huang, W.; Rossini, A.J.; Wang, C.-Z.; Ho, K.-M.; Hadermann, J.; Zaikina, J., V |
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Title |
Topochemical deintercalation of Li from layered LiNiB : toward 2D MBene |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of The American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| |
Volume |
143 |
Issue |
11 |
Pages |
4213-4223 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The pursuit of two-dimensional (2D) borides, MBenes, has proven to be challenging, not the least because of the lack of a suitable precursor prone to the deintercalation. Here, we studied room-temperature topochemical deintercalation of lithium from the layered polymorphs of the LiNiB compound with a considerable amount of Li stored in between [NiB] layers (33 at. % Li). Deintercalation of Li leads to novel metastable borides (Li similar to 0.5NiB) with unique crystal structures. Partial removal of Li is accomplished by exposing the parent phases to air, water, or dilute HCl under ambient conditions. Scanning transmission electron microscopy and solid-state Li-7 and B-1(1) NMR spectroscopy, combined with X-ray pair distribution function (PDF) analysis and DFT calculations, were utilized to elucidate the novel structures of (Li similar to 0.5NiB) and the mechanism of Li-deintercalation. We have shown that the deintercalation of Li proceeds via a “zip-lock” mechanism, leading to the condensation of single [NiB] layers into double or triple layers bound via covalent bonds, resulting in structural fragments with Li[NiB](2) and Li[NiB](3) compositions. The crystal structure of Li similar to 0.5NiB is best described as an intergrowth of the ordered single [NiB], double [NiB](2), or triple [NiB](3) layers alternating with single Li layers; this explains its structural complexity. The formation of double or triple [NiB] layers induces a change in the magnetic behavior from temperature-independent paramagnets in the parent LiNiB compounds to the spin-glassiness in the deintercalated Li similar to 0.5NiB counterparts. LiNiB compounds showcase the potential to access a plethora of unique materials, including 2D MBenes (NiB). |
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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 |
000634761500021 |
Publication Date |
2021-03-15 |
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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 |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.858 |
Times cited |
|
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 13.858 |
| |
Call Number |
UA @ admin @ c:irua:177697 |
Serial |
6790 |
| Permanent link to this record |
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Author |
Skorikov, A.; Heyvaert, W.; Albrecht, W.; Pelt, D.M.; Bals, S. |
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Title |
EMAT Simulated 3D Nanoparticle Structures Dataset |
Type |
Dataset |
| |
Year |
2021 |
Publication |
|
Abbreviated Journal |
|
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Volume |
|
Issue |
|
Pages |
|
| |
Keywords |
Dataset; Electron microscopy for materials research (EMAT) |
| |
Abstract |
This dataset contains 1000 simulated nanoparticle-like 3D structures and noisy EDX-like elemental maps based on them. These data are intended to be used for quantitative analysis of data processing methods in (EDX) tomography of nanoparticles and training the data-driven approaches for these tasks. The dataset is structured as follows: voxel_data/clean 3D voxel grid representation of the simulated nanoparticles. Voxel intensities are adjusted so that the total intensity equals 103. All 3D structures have unique identifiers in 0..999 range. The data derived from a 3D structure preserves this unique identifier. sinograms/clean Tilt series of projection images obtained from the corresponding 3D structures over an angular range of -75..75 degrees with a tilt step of 10 degrees to simulate a typical tilt series used in EDX tomography. Total intensity in each projection image equals 103. sinograms/noisy Tilt series of projection images corrupted with Poisson noise and an additional spatially uniform background noise. projections/clean Projection images extracted from the clean tilt series at 0 degrees tilt angle. projections/noisy Projection images extracted from the noisy tilt series at 0 degrees tilt angle. images/clean Visualizations of the clean projections as PNG images with the intensity range adjusted to 0..255 images/noisy Visualizations of the noisy projections as PNG images with the intensity range adjusted to 0..255 |
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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 |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ admin @ c:irua:180615 |
Serial |
6838 |
| Permanent link to this record |
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Author |
Zhang, Z.; Bourgeois, L.; Zhang, Y.; Rosalie, J.M.; Medhekar, N. |
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Title |
Advanced imaging and simulations of precipitate interfaces in aluminium alloys and their role in phase transformations |
Type |
P1 Proceeding |
| |
Year |
2020 |
Publication |
MATEC web of conferences
T2 – 17th International Conference on Aluminium Alloys (ICAA), October 26-29, 2020 |
Abbreviated Journal |
|
| |
Volume |
|
Issue |
|
Pages |
09003 |
| |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Precipitation is accompanied by the formation and migration of heterophase interfaces. Using the combined approach of advanced imaging and atomistic simulations, we studied the precipitate-matrix interfaces in various aluminium alloy systems, aiming to resolve their detailed atomic structures and illuminate their role in phase transformations. |
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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 |
000652552200053 |
Publication Date |
2020-11-05 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
326 |
Series Issue |
|
Edition |
|
| |
ISSN |
2261-236x; 2274-7214 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ admin @ c:irua:179147 |
Serial |
6851 |
| Permanent link to this record |
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Author |
Feng, H.L.; Kang, C.-J.; Manuel, P.; Orlandi, F.; Su, Y.; Chen, J.; Tsujimoto, Y.; Hadermann, J.; Kotliar, G.; Yamaura, K.; McCabe, E.E.; Greenblatt, M. |
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Title |
Antiferromagnetic order breaks inversion symmetry in a metallic double perovskite, Pb₂NiOsO₆ |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
33 |
Issue |
11 |
Pages |
4188-4195 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
A polycrystalline sample of Pb2NiOsO6 was synthesized under high-pressure (6 GPa) and high-temperature (1575 K) conditions. Pb2NiOsO6 crystallizes in a monoclinic double perovskite structure with a centrosymmetric space group P2(1)/n at room temperature. Pb2NiOsO6 is metallic down to 2 K and shows a single antiferromagnetic (AFM) transition at T-N = 58 K. Pb2NiOsO6 is a new example of a metallic and AFM oxide with three-dimensional connectivity. Neutron powder diffraction and first-principles calculation studies indicate that both Ni and Os moments are ordered below T-N and the AFM magnetic order breaks inversion symmetry. This loss of inversion symmetry driven by AFM order is unusual in metallic systems, and the 3d-Sd double-perovskite oxides represent a new class of noncentrosymmetric AFM metallic oxides. |
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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 |
000661521800032 |
Publication Date |
2021-05-26 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0897-4756; 1520-5002 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
9.466 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 9.466 |
| |
Call Number |
UA @ admin @ c:irua:179679 |
Serial |
6854 |
| Permanent link to this record |
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|
Author |
Mahadi, A.H.; Ye, L.; Fairclough, S.M.; Qu, J.; Wu, S.; Chen, W.; Papaioannou, E.; Ray, B.; Pennycook, T.J.; Haigh, S.J.; Young, N.P.; Tedsree, K.; Metcalfe, I.S.; Tsang, S.C.E. |
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Title |
Beyond surface redox and oxygen mobility at pd-polar ceria (100) interface : underlying principle for strong metal-support interactions in green catalysis |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Applied Catalysis B-Environmental |
Abbreviated Journal |
Appl Catal B-Environ |
| |
Volume |
270 |
Issue |
|
Pages |
118843 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
When ceria is used as a support for many redox catalysis involved in green catalysis, it is well-known that the overlying noble metal can gain access to a significant quantity of oxygen atoms with high mobility and fast reduction and oxidation properties under mild conditions. However, it is as yet unclear what the underlying principle and the nature of the ceria surface involved are. By using two tailored morphologies of ceria nanocrystals, namely cubes and rods, it is demonstrated from Scanning Transmission Electron Microscopy with Electron Energy Loss Spectroscopy (STEM-EELS) mapping and Pulse Isotopic Exchange (PIE) that ceria nano-cubes terminated with a polar surface (100) can give access to more than the top most layer of surface oxygen atoms. Also, they give higher oxygen mobility than ceria nanorods with a non-polar facet of (110). A new insight for the possible additional role of polar ceria surface plays in the oxygen mobility is obtained from Density Functional Theory (DFT) calculations which suggest that the (100) surface sites that has more than half-filled O on same plane can drive oxygen atoms to oxidise adsorbate(s) on Pd due to the strong electrostatic repulsion. |
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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 |
000526110500007 |
Publication Date |
2020-03-04 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0926-3373 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
22.1 |
Times cited |
|
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 22.1; 2020 IF: 9.446 |
| |
Call Number |
UA @ admin @ c:irua:183959 |
Serial |
6856 |
| Permanent link to this record |
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Author |
Villarreal, R.; Lin, P.-C.; Faraji, F.; Hassani, N.; Bana, H.; Zarkua, Z.; Nair, M.N.; Tsai, H.-C.; Auge, M.; Junge, F.; Hofsaess, H.C.; De Gendt, S.; De Feyter, S.; Brems, S.; Ahlgren, E.H.; Neyts, E.C.; Covaci, L.; Peeters, F.M.; Neek-Amal, M.; Pereira, L.M.C. |
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Title |
Breakdown of universal scaling for nanometer-sized bubbles in graphene |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
| |
Volume |
21 |
Issue |
19 |
Pages |
8103-8110 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
We report the formation of nanobubbles on graphene with a radius of the order of 1 nm, using ultralow energy implantation of noble gas ions (He, Ne, Ar) into graphene grown on a Pt(111) surface. We show that the universal scaling of the aspect ratio, which has previously been established for larger bubbles, breaks down when the bubble radius approaches 1 nm, resulting in much larger aspect ratios. Moreover, we observe that the bubble stability and aspect ratio depend on the substrate onto which the graphene is grown (bubbles are stable for Pt but not for Cu) and trapped element. We interpret these dependencies in terms of the atomic compressibility of the noble gas as well as of the adhesion energies between graphene, the substrate, and trapped atoms. |
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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 |
000709549100026 |
Publication Date |
2021-09-14 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
12.712 |
Times cited |
24 |
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 12.712 |
| |
Call Number |
UA @ admin @ c:irua:184137 |
Serial |
6857 |
| Permanent link to this record |
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| |
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Author |
Golovachev, I.B.; Mychinko, M.Y.; Volkova, N.E.; Gavrilova, L.Y.; Raveau, B.; Maignan, A.; Cherepanov, V.A. |
| |
Title |
Effect of cobalt content on the properties of quintuple perovskites Sm₂Ba₃Fe₅-xCoxO₁₅-δ |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of Solid State Chemistry |
Abbreviated Journal |
J Solid State Chem |
| |
Volume |
301 |
Issue |
|
Pages |
122324 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Quintuple perovskites Sm2Ba3Fe5-xCoxO15-delta = 0.5, 1.0 and 1.5) have been prepared by glycerin-nitrate tech- nique in air. The phase purity was confirmed by XRD. Partial substitution of Co for Fe decreases the oxygen content and thus the mean oxidation state of 3d-metals. It also slightly decreases the thermal expansion coefficient of oxides. Positive value of the Seebeck coefficient confirmed p-type conductivity, though the thermopower decreases as the Co content increases. The temperature dependence of electrical conductivity reveals a maximum at 550-750 degrees C. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000684543700028 |
Publication Date |
2021-06-03 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
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 |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 2.299 |
| |
Call Number |
UA @ admin @ c:irua:181656 |
Serial |
6864 |
| Permanent link to this record |
| |
|
| |
|
Author |
Gonzalez-Nelson, A.; Mula, S.; Simenas, M.; Balciunas, S.; Altenhof, A.R.; Vojvodin, C.S.; Canossa, S.; Banys, J.; Schurko, R.W.; Coudert, F.-X.; van der Veen, M.A. |
| |
Title |
Emergence of coupled rotor dynamics in metal-organic frameworks via tuned steric interactions |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of The American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| |
Volume |
143 |
Issue |
31 |
Pages |
12053-12062 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The organic components in metal-organic frameworks (MOFs) are unique: they are embedded in a crystalline lattice, yet, as they are separated from each other by tunable free space, a large variety of dynamic behavior can emerge. These rotational dynamics of the organic linkers are especially important due to their influence over properties such as gas adsorption and kinetics of guest release. To fully exploit linker rotation, such as in the form of molecular machines, it is necessary to engineer correlated linker dynamics to achieve their cooperative functional motion. Here, we show that for MIL-53, a topology with closely spaced rotors, the phenylene functionalization allows researchers to tune the rotors' steric environment, shifting linker rotation from completely static to rapid motions at frequencies above 100 MHz. For steric interactions that start to inhibit independent rotor motion, we identify for the first time the emergence of coupled rotation modes in linker dynamics. These findings pave the way for function-specific engineering of gear-like cooperative motion in MOFs. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000684581100022 |
Publication Date |
2021-07-29 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.858 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 13.858 |
| |
Call Number |
UA @ admin @ c:irua:180504 |
Serial |
6867 |
| Permanent link to this record |
| |
|
| |
|
Author |
Marteleur, M.; Idrissi, H.; Amin-Ahmadi, B.; Prima, F.; Schryvers, D.; Jacques, P.J. |
| |
Title |
On the nucleation mechanism of {112} < 111 > mechanical twins in as-quenched beta metastable Ti-12 wt.% Mo alloy |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Materialia |
Abbreviated Journal |
|
| |
Volume |
7 |
Issue |
|
Pages |
Unsp 100418 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Recently developed beta-metastable Ti grades take advantage of the simultaneous activation of TRIP and TWIP effects for enhancing their work hardening rate. However, the role of each plasticity mechanism on the macroscopic mechanical response is still unclear. In this work, the nucleation mechanism of the first activated plasticity mechanism, namely {112} < 111 > twinning, was investigated. Firstly, post-mortem TEM analysis showed that twins nucleate on pre-existing microstructural defects such as thermal jogs with the zonal dislocation mechanism. The precipitation of the omega phase on twin boundaries has been observed, as well as the emission of numerous dislocations from super-jogs present in these twin boundaries. It is also shown that {112} < 111 > twins act as effective dislocation sources for the subsequent plasticity mechanisms such as beta -> alpha '' martensitic transformation and {332} < 111 > twinning. Secondly, in situ TEM tensile testing of the investigated Ti grade highlighted the primary role of the initial defect configuration present in the microstructure. It is shown that twins cannot nucleate without the presence of specific defects allowing the triggering of the dislocation decomposition needed for the twinning mechanism highlighted in investigated bulk samples. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
|
| |
Language |
|
Wos |
000537131000052 |
Publication Date |
2019-07-31 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2589-1529 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
| |
Notes |
|
Approved |
no |
| |
Call Number |
UA @ admin @ c:irua:170326 |
Serial |
6875 |
| Permanent link to this record |
| |
|
| |
|
Author |
Bartholomeeusen, E.; De Cremer, G.; Kennes, K.; Hammond, C.; Hermans, I.; Lu, J.-B.; Schryvers, D.; Jacobs, P.A.; Roeffaers, M.B.J.; Hofkens, J.; Sels, B.F.; Coutino-Gonzalez, E. |
| |
Title |
Optical encoding of luminescent carbon nanodots in confined spaces |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Chemical Communications |
Abbreviated Journal |
Chem Commun |
| |
Volume |
57 |
Issue |
90 |
Pages |
11952-11955 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Stable emissive carbon nanodots were generated in zeolite crystals using near infrared photon irradiation gradually converting the occluded organic template, originally used to synthesize the zeolite crystals, into discrete luminescent species consisting of nano-sized carbogenic fluorophores, as ascertained using Raman microscopy, and steady-state and time-resolved spectroscopic techniques. Photoactivation in a confocal laser fluorescence microscope allows 3D resolved writing of luminescent carbon nanodot patterns inside zeolites providing a cost-effective and non-toxic alternative to previously reported metal-based nanoclusters confined in zeolites, and opens up opportunities in bio-labelling and sensing applications. |
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Address |
|
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Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000711122000001 |
Publication Date |
2021-10-26 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1359-7345; 1364-548x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.319 |
Times cited |
|
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 6.319 |
| |
Call Number |
UA @ admin @ c:irua:184147 |
Serial |
6876 |
| Permanent link to this record |
| |
|
| |
|
Author |
Psilodimitrakopoulos, S.; Orekhov, A.; Mouchliadis, L.; Jannis, D.; Maragkakis, G.M.; Kourmoulakis, G.; Gauquelin, N.; Kioseoglou, G.; Verbeeck, J.; Stratakis, E. |
| |
Title |
Optical versus electron diffraction imaging of Twist-angle in 2D transition metal dichalcogenide bilayers |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
npj 2D Materials and Applications |
Abbreviated Journal |
|
| |
Volume |
5 |
Issue |
1 |
Pages |
77 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Atomically thin two-dimensional (2D) materials can be vertically stacked with van der Waals bonds, which enable interlayer coupling. In the particular case of transition metal dichalcogenide (TMD) bilayers, the relative direction between the two monolayers, coined as twist-angle, modifies the crystal symmetry and creates a superlattice with exciting properties. Here, we demonstrate an all-optical method for pixel-by-pixel mapping of the twist-angle with a resolution of 0.55(degrees), via polarization-resolved second harmonic generation (P-SHG) microscopy and we compare it with four-dimensional scanning transmission electron microscopy (4D STEM). It is found that the twist-angle imaging of WS2 bilayers, using the P-SHG technique is in excellent agreement with that obtained using electron diffraction. The main advantages of the optical approach are that the characterization is performed on the same substrate that the device is created on and that it is three orders of magnitude faster than the 4D STEM. We envisage that the optical P-SHG imaging could become the gold standard for the quality examination of TMD superlattice-based devices. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
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Editor |
|
| |
Language |
|
Wos |
000694849200001 |
Publication Date |
2021-09-09 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2397-7132 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
4 |
Open Access |
OpenAccess |
| |
Notes |
This research has been co-financed by the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call European R & T Cooperation-Grant Act of Hellenic Institutions that have successfully participated in Joint Calls for Proposals of European Networks ERA NETS (National project code: GRAPH-EYE T8 Epsilon Rho Alpha 2-00009 and European code: 26632, FLAGERA). L.M., G.Ko. and G.Ki. acknowledge funding by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant” (Project No: HFRI-FM17-3034). GKi, S.P. and G.M.M. acknowledge funding from a research co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme “Human Resources Development, Education and Lifelong Learning 2014-2020” in the context of the project “Crystal quality control of two-dimensional materials and their heterostructures via imaging of their non-linear optical properties” (MIS 5050340)“. J.V acknowledges funding from FWO G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund, EU. J.V. and N.G. acknowledge funding from the European Union under the Horizon 2020 programme within a contract for Integrating Activities for Advanced Communities No 823717-ESTEEM3. J.V. N.G. and A.O. acknowledge funding through a GOA project ”Solarpaint" of the University of Antwerp. |
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ admin @ c:irua:181610 |
Serial |
6877 |
| Permanent link to this record |
| |
|
| |
|
Author |
Bae, J.; Cichocka, M.O.; Zhang, Y.; Bacsik, Z.; Bals, S.; Zou, X.; Willhammar, T.; Hong, S.B. |
| |
Title |
Phase transformation behavior of a two-dimensional zeolite |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
|
| |
Volume |
58 |
Issue |
30 |
Pages |
10230-10235 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Understanding the molecular-level mechanisms of phase transformation in solids is of fundamental interest for functional materials such as zeolites. Two-dimensional (2D) zeolites, when used as shape-selective catalysts, can offer improved access to the catalytically active sites and a shortened diffusion length in comparison with their 3D analogues. However, few materials are known to maintain both their intralayer microporosity and structure during calcination for organic structure-directing agent (SDA) removal. Herein we report that PST-9, a new 2D zeolite which has been synthesized via the multiple inorganic cation approach and fulfills the requirements for true layered zeolites, can be transformed into the small-pore zeolite EU-12 under its crystallization conditions through the single-layer folding process, but not through the traditional dissolution/recrystallization route. We also show that zeolite crystal growth pathway can differ according to the type of organic SDAs employed. |
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Address |
|
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000476452700030 |
Publication Date |
2019-05-22 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1433-7851; 0570-0833 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
2 |
Open Access |
OpenAccess |
| |
Notes |
We acknowledge financial support from National Creative Research Initiative Program (2012R1A3A-2048833) through the National Research Foundation of Korea, the National Research Council of Science & Technology (CRC-14-1-KRICT) grant by the Korea government (MSIP), the Swedish Research Council (2017-04321), and the Knut and Alice Wallenberg Foundation (KAW) through the project grant 3DEM-NATUR (2012.0112). T.W. acknowledges an international postdoc grant from the Swedish Research Council (2014-06948). |
Approved |
no |
| |
Call Number |
UA @ admin @ c:irua:181233 |
Serial |
6878 |
| Permanent link to this record |
| |
|
| |
|
Author |
Baral, P.; Orekhov, A.; Dohmen, R.; Coulombier, M.; Raskin, J.P.; Cordier, P.; Idrissi, H.; Pardoen, T. |
| |
Title |
Rheology of amorphous olivine thin films characterized by nanoindentation |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Acta Materialia |
Abbreviated Journal |
Acta Mater |
| |
Volume |
219 |
Issue |
|
Pages |
117257 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
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 |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000706867800004 |
Publication Date |
2021-08-19 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1359-6454 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.301 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 5.301 |
| |
Call Number |
UA @ admin @ c:irua:182592 |
Serial |
6882 |
| Permanent link to this record |
| |
|
| |
|
Author |
Yang, M.; Orekhov, A.; Hu, Z.-Y.; Feng, M.; Jin, S.; Sha, G.; Li, K.; Samaee, V.; Song, M.; Du, Y.; Van Tendeloo, G.; Schryvers, D. |
| |
Title |
Shearing and rotation of β'' and β' precipitates in an Al-Mg-Si alloy under tensile deformation : in-situ and ex-situ studies |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Acta Materialia |
Abbreviated Journal |
Acta Mater |
| |
Volume |
220 |
Issue |
|
Pages |
117310 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The interaction between dislocations and nano-precipitates during deformation directly influences hardening response of precipitation-strengthening metals such as Al-Mg-Si alloys. However, how coherent and semi-coherent nano-precipitates accommodate external deformation applied to an Al alloy remains to be elucidated. In-situ tensile experiments in a transmission electron microscope (TEM) were conducted to study the dynamic process of dislocations cutting through coherent needle-like beta '' precipitates with diameters of 3 similar to 8 nm. Comprehensive investigations using in-situ, ex-situ TEM and atom probe tomography uncovered that beta '' precipitates were firstly sheared into small fragments, and then the rotation of the fragments, via sliding along precipitate/matrix interfaces, destroyed their initially coherent interface with the Al matrix. In contrast, semi-coherent beta' precipitates with sizes similar to beta '' were more difficult to be fragmented and accumulation of dislocations at the interface increased interface misfit between beta' and the Al matrix. Consequently, beta' precipitates could basically maintain their needle-like shape after the tensile deformation. This research gains new insights into the interaction between nano-precipitates and dislocations. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
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Address |
|
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000705535300005 |
Publication Date |
2021-09-12 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1359-6454 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.301 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 5.301 |
| |
Call Number |
UA @ admin @ c:irua:182528 |
Serial |
6884 |
| Permanent link to this record |
| |
|
| |
|
Author |
Penders, A.; Konstantinovic, M.J.; Van Renterghem, W.; Bosch, R.W.; Schryvers, D. |
| |
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 |
| |
Volume |
|
Issue |
|
Pages |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
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 |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000695956400001 |
Publication Date |
2021-09-14 |
| |
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 |
| |
Call Number |
UA @ admin @ c:irua:181533 |
Serial |
6892 |
| Permanent link to this record |
| |
|
| |
|
Author |
Mallick, S.; Khalsa, G.; Kaaret, J.Z.; Zhang, W.; Batuk, M.; Gibbs, A.S.; Hadermann, J.; Halasyamani, P.S.; Benedek, N.A.; Hayward, M.A. |
| |
Title |
The influence of the 6s² configuration of Bi³+ on the structures of A ' BiNb₂O₇ (A ' = Rb, Na, Li) layered perovskite oxides |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
|
| |
Volume |
50 |
Issue |
42 |
Pages |
15359-15369 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Solid state compounds which exhibit non-centrosymmetric crystal structures are of great interest due to the physical properties they can exhibit. The 'hybrid improper' mechanism – in which two non-polar distortion modes couple to, and stabilize, a further polar distortion mode, yielding an acentric crystal structure – offers opportunities to prepare a range of novel non-centrosymmetric solids, but examples of compounds exhibiting acentric crystal structures stabilized by this mechanism are still relatively rare. Here we describe a series of bismuth-containing layered perovskite oxide phases, RbBiNb2O7, LiBiNb2O7 and NaBiNb2O7, which have structural frameworks compatible with hybrid-improper ferroelectricity, but also contain Bi3+ cations which are often observed to stabilize acentric crystal structures due to their 6s(2) electronic configurations. Neutron powder diffraction analysis reveals that RbBiNb2O7 and LiBiNb2O7 adopt polar crystal structures (space groups I2cm and B2cm respectively), compatible with stabilization by a trilinear coupling of non-polar and polar modes. The Bi3+ cations present are observed to enhance the magnitude of the polar distortions of these phases, but are not the primary driver for the acentric structure, as evidenced by the observation that replacing the Bi3+ cations with Nd3+ cations does not change the structural symmetry of the compounds. In contrast the non-centrosymmetric, but non-polar structure of NaBiNb2O7 (space group P2(1)2(1)2(1)) differs significantly from the centrosymmetric structure of NaNdNb2O7, which is attributed to a second-order Jahn-Teller distortion associated with the presence of the Bi3+ cations. |
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Address |
|
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Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000706651100001 |
Publication Date |
2021-10-05 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1477-9234 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ admin @ c:irua:182584 |
Serial |
6893 |
| Permanent link to this record |
| |
|
| |
|
Author |
Lezaack, M.B.; Hannard, F.; Zhao, L.; Orekhov, A.; Adrien, J.; Miettinen, A.; Idrissi, H.; Simar, A. |
| |
Title |
Towards ductilization of high strength 7XXX aluminium alloys via microstructural modifications obtained by friction stir processing and heat treatments |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Materialia |
Abbreviated Journal |
|
| |
Volume |
20 |
Issue |
|
Pages |
101248 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
High strength 7XXX aluminium series reach exceptional strength, higher than all other industrial aluminium alloys. However, they suffer from a lack of ductility compared to softer series. This work presents a procedure to improve the ductility of 7475 Al alloy in high strength condition, reaching a true fracture strain of 70% at full 500 MPa T6 yield strength. Using friction stir processing (FSP) and post-FSP heat treatments, 100% of industrial rolled material T6 yield stress is maintained but a 180% increase in fracture strain is measured for the processed material. This ductility improvement is studied by in-situ synchrotron X-ray tomography and is explained by the reduction of intermetallic particles size and the homogenization of their spatial distribution. Furthermore, the microstructure after FSP shows equiaxed refined grains which favour crack deviation as opposed to large cracks parallel to the elongated coarse grains in rolled plate. These results are paving the way to better formability and crashworthiness of 7XXX alloys. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000718127100006 |
Publication Date |
2021-10-19 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
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Edition |
|
| |
ISSN |
2589-1529 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ admin @ c:irua:184145 |
Serial |
6894 |
| Permanent link to this record |
