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Records |
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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 |
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Volume |
288 |
Issue |
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Pages |
119997 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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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Wos |
000632996500002 |
Publication Date |
2021-02-17 |
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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 |
0926-3373 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.446 |
Times cited |
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Open Access  |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 9.446 |
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Call Number |
UA @ admin @ c:irua:177621 |
Serial |
6789 |
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| 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 |
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| |
Volume |
143 |
Issue |
11 |
Pages |
4213-4223 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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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Wos |
000634761500021 |
Publication Date |
2021-03-15 |
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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 |
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Series Issue |
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Edition |
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ISSN |
0002-7863 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.858 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 13.858 |
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Call Number |
UA @ admin @ c:irua:177697 |
Serial |
6790 |
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| Permanent link to this record |
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Author |
Xi, J.; Yang, S.; Silvioli, L.; Cao, S.; Liu, P.; Chen, Q.; Zhao, Y.; Sun, H.; Hansen, J.N.; Haraldsted, J.-P.B.; Kibsgaard, J.; Rossmeisl, J.; Bals, S.; Wang, S.; Chorkendorff, I. |
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Title |
Highly active, selective, and stable Pd single-atom catalyst anchored on N-doped hollow carbon sphere for electrochemical H₂O₂ synthesis under acidic conditions |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Journal Of Catalysis |
Abbreviated Journal |
J Catal |
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Volume |
393 |
Issue |
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Pages |
313-323 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Single-atom catalysts (SACs) have recently attracted broad scientific interests due to their unique structural feature, the single-atom dispersion. Optimized electronic structure as well as high stability are required for single-atom catalysts to enable efficient electrochemical production of H2O2. Herein, we report a facile synthesis method that stabilizes atomic Pd species on the reduced graphene oxide/Ndoped carbon hollow carbon nanospheres (Pd1/N-C). Pd1/N-C exhibited remarkable electrochemical H2O2 production rate with high faradaic efficiency, reaching 80%. The single-atom structure and its high H2O2 production rate were maintained even after 10,000 cycle stability test. The existence of single-atom Pd as well as its coordination with N species is responsible for its high activity, selectivity, and stability. The N coordination number and substrate doping around Pd atoms are found to be critical for an optimized adsorption energy of intermediate *OOH, resulting in efficient electrochemical H2O2 production. (C) 2020 Elsevier Inc. All rights reserved. |
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Wos |
000640923500003 |
Publication Date |
2020-11-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9517 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.844 |
Times cited |
40 |
Open Access |
Not_Open_Access |
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Notes |
This research was financially supported by the National Natural Science Foundation of China (No. 51772110), Natural Science Foundation of Hubei Province (No. 2019CFB539), Danmarks Innovationsfond within the ProActivE project (5160-00003B), Villum Foundation V-SUSTAIN grant 9455 to the Villum Center for the Science of Sustainable Fuels and Chemicals, the Carlsberg Foundation grant CF18-0435, the Institutional Research Program (2E30220) of the Korea Institute of Science and Technology (KIST), Shenzhen Science and Technology Plan under Grant (JCYJ20170818160751460) and the Open Project of Key Laboratory of Green Chemical Engineering Process of Ministry of Education (No. GCP20200205). The authors would like to acknowledge the Analytical and Testing Center of Huazhong University of Science and Technology and the Wuhan National Laboratory for Optoelectronics for SEM, TEM, Raman and XPS measurements. |
Approved |
Most recent IF: 6.844 |
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Call Number |
UA @ admin @ c:irua:178321 |
Serial |
6796 |
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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 |
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Year |
2021 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Dataset; Electron microscopy for materials research (EMAT) |
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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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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:180615 |
Serial |
6838 |
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Author |
Shi, R.; Choudhuri, D.; Kashiwar, A.; Dasari, S.; Wang, Y.; Banerjee, R.; Banerjee, D. |
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Title |
α phase growth and branching in titanium alloys |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Philosophical magazine |
Abbreviated Journal |
Philos Mag |
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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 morphology and spatial distribution of alpha (α) precipitates have been mapped as a function of Mo content in Ti-Mo binary alloys employing a combinatorial approach. Heat-treatments were carried out on compositionally graded Ti-xMo samples processed using a rapid throughput laser engineered net shape (LENS) process. The composition space spans 1.5 at% to 6 at% Mo with ageing at 750°C, 650°C and 600°C following a β solution treatment. Three distinct regimes of α morphology and distribution were observed. These are colony-dominated microstructures originating from grain boundary α allotriomorphs, bundles of intragranular α laths, and homogeneously distributed individual fine-scale α laths. Branching of the α precipitates was observed in all these domains in a manner reminiscent of solid-state dendritic growth. The phenomenon is particularly apparent at low volume fractions of α. Similar features are present in a wide variety of alloy compositions. 3-dimensional features of such branched structures have been analysed. Simulation of the branching process by phase field methods incorporating anisotropy in the α/β interface energy and elasticity suggests that it can be initiated at growth ledges present at broad faces of the α laths, driven by the enhancement of the diffusion flux at these steps. The dependence of branching on various parameters such as supersaturation and diffusivity, and microstructural features like ledge height and distribution and the presence of adjacent α variants has been evaluated. |
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Language |
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Wos |
000722082700001 |
Publication Date |
2021-11-24 |
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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 |
1478-6435 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.505 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 1.505 |
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Call Number |
UA @ admin @ c:irua:183616 |
Serial |
6849 |
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| Permanent link to this record |
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Author |
Peng, X.; Peng, H.; Zhao, K.; Zhang, Y.; Xia, F.; Lyu, J.; Van Tendeloo, G.; Sun, C.; Wu, J. |
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Title |
Direct visualization of atomic-scale heterogeneous structure dynamics in MnO₂ nanowires |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
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Volume |
13 |
Issue |
28 |
Pages |
33644-33651 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Manganese oxides are attracting great interest owing to their rich polymorphism and multiple valent states, which give rise to a wide range of applications in catalysis, capacitors, ion batteries, and so forth. Most of their functionalities are connected to transitions among the various polymorphisms and Mn valences. However, their atomic-scale dynamics is still a great challenge. Herein, we discovered a strong heterogeneity in the crystalline structure and defects, as well as in the Mn valence state. The transitions are studied by in situ transmission electron microscopy (TEM), and they involve a complex ordering of [MnO6] octahedra as the basic building tunnels. MnO2 nanowires synthesized using solution-based hydrothermal methods usually exhibit a large number of multiple polymorphism impurities with different tunnel sizes. Upon heating, MnO2 nanowires undergo a series of stoichiometric polymorphism changes, followed by oxygen release toward an oxygen-deficient spinel and rock-salt phase. The impurity polymorphism exhibits an abnormally high stability with interesting small-large-small tunnel size transition, which is attributed to a preferential stabilizer (K+) concentration, as well as a strong competition of kinetics and thermodynamics. Our results unveil the complicated intergrowth of polymorphism impurities in MnO2, which provide insights into the heterogeneous kinetics, thermodynamics, and transport properties of the tunnel-based building blocks. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000677540900101 |
Publication Date |
2021-07-08 |
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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 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.504 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 7.504 |
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Call Number |
UA @ admin @ c:irua:180450 |
Serial |
6861 |
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Author |
Neelisetty, K.K.; Kumar C.N., S.; Kashiwar, A.; Scherer, T.; Chakravadhanula, V.S.K.; Kuebel, C. |
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Title |
Novel thin film lift-off process for in situ TEM tensile characterization |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Microscopy And Microanalysis |
Abbreviated Journal |
Microsc Microanal |
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Volume |
27 |
Issue |
S1 |
Pages |
216-217 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
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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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Wos |
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Publication Date |
2021-07-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1431-9276 |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
1.891 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 1.891 |
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Call Number |
UA @ admin @ c:irua:183617 |
Serial |
6873 |
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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. |
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Title |
Optical encoding of luminescent carbon nanodots in confined spaces |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Chemical Communications |
Abbreviated Journal |
Chem Commun |
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Volume |
57 |
Issue |
90 |
Pages |
11952-11955 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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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Place of Publication |
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Wos |
000711122000001 |
Publication Date |
2021-10-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1359-7345; 1364-548x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.319 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 6.319 |
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Call Number |
UA @ admin @ c:irua:184147 |
Serial |
6876 |
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Author |
Liang, Q.; Yang, D.; Xia, F.; Bai, H.; Peng, H.; Yu, R.; Yan, Y.; He, D.; Cao, S.; Van Tendeloo, G.; Li, G.; Zhang, Q.; Tang, X.; Wu, J. |
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Title |
Phase-transformation-induced giant deformation in thermoelectric Ag₂Se semiconductor |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
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Volume |
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Issue |
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Pages |
2106938 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In most semiconducting metal chalcogenides, a large deformation is usually accompanied by a phase transformation, while the deformation mechanism remains largely unexplored. Herein, a phase-transformation-induced deformation in Ag2Se is investigated by in situ transmission electron microscopy, and a new ordered high-temperature phase (named as alpha '-Ag2Se) is identified. The Se-Se bonds are folded when the Ag+-ion vacancies are ordered and become stretched when these vacancies are disordered. Such a stretch/fold of the Se-Se bonds enables a fast and large deformation occurring during the phase transition. Meanwhile, the different Se-Se bonding states in alpha-, alpha '-, beta-Ag2Se phases lead to the formation of a large number of nanoslabs and the high concentration of dislocations at the interface, which flexibly accommodate the strain caused by the phase transformation. This study reveals the atomic mechanism of the deformation in Ag2Se inorganic semiconductors during the phase transition, which also provides inspiration for understanding the phase transition process in other functional materials. |
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Wos |
000695142800001 |
Publication Date |
2021-09-13 |
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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 |
1616-301x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.124 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 12.124 |
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Call Number |
UA @ admin @ c:irua:181527 |
Serial |
6879 |
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Author |
Zhou, X.-G.; Yang, C.-Q.; Sang, X.; Li, W.; Wang, L.; Yin, Z.-W.; Han, J.-R.; Li, Y.; Ke, X.; Hu, Z.-Y.; Cheng, Y.-B.; Van Tendeloo, G. |
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Title |
Probing the electron beam-induced structural evolution of halide perovskite thin films by scanning transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
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Volume |
125 |
Issue |
19 |
Pages |
10786-10794 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
A deep understanding of the fine structure at the atomic scale of halide perovskite materials has been limited by their sensitivity to the electron beam that is widely used for structural characterization. The sensitivity of a gamma-CsPbIBr2 perovskite thin film under electron beam irradiation is revealed by scanning transmission electron microscopy (STEM) through a universal large-range electron dose measurement, which is based on discrete single-electron events in the STEM mode. Our research indicates that the gamma-CsPbIBr2 thin film undergoes structural changes with increasing electron overall dose (e(-).A(-2)) rather than dose rate (e(-).A(-2).s(-1)), which suggests that overall dose is the key operative parameter. The electron beam-induced structural evolution of gamma-CsPbIBr2 is monitored by fine control of the electron beam dose, together with the analysis of high-resolution (S)TEM, diffraction, and energy-dispersive X-ray spectroscopy. Our results show that the gamma-CsPbIBr2 phase first forms an intermediate phase [e.g., CsPb(1-x)(IBr)((3-y))] with a superstructure of ordered vacancies in the pristine unit cell, while a fraction of Pb2+ is reduced to Pb-0. As the electron dose increases, Pb nanoparticles precipitate, while the remaining framework forms the Cs2IBr phase, accompanied by some amorphization. This work provides guidelines to minimize electron beam irradiation artifacts for atomic-resolution imaging on CsPbIBr2 thin films. |
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Wos |
000655640900061 |
Publication Date |
2021-05-11 |
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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 |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.536 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.536 |
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| |
Call Number |
UA @ admin @ c:irua:179187 |
Serial |
6880 |
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| Permanent link to this record |
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| |
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Author |
Zhao, H.; Li, C.-F.; Hu, Z.-Y.; Liu, J.; Li, Y.; Hu, J.; Van Tendeloo, G.; Chen, L.-H.; Su, B.-L. |
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| |
Title |
Size effect of bifunctional gold in hierarchical titanium oxide-gold-cadmium sulfide with slow photon effect for unprecedented visible-light hydrogen production |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of Colloid And Interface Science |
Abbreviated Journal |
J Colloid Interf Sci |
|
| |
Volume |
604 |
Issue |
|
Pages |
131-139 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Gold nanoparticles (Au NPs) with surface plasmonic resonance (SPR) effect and excellent internal electron transfer ability have widely been combined with semiconductors for photocatalysis. However, the in-depth effects of Au NPs in multicomponent photocatalysts have not been completely understood. Herein, ternary titanium oxide-gold-cadmium sulfide (TiO2-Au-CdS, TAC) photocatalysts, based on hierarchical TiO2 inverse opal photonic crystal structure with different Au NPs sizes have been designed to reveal the SPR effect and internal electron transfer of Au NPs in the presence of slow photon effect. It appears that the SPR effect and internal electron transfer ability of Au NPs, depending on their sizes, play a synergistic effect on the photocatalytic enhancement. The ternary TAC-10 photocatalyst with – 10 nm Au NPs demonstrates an unprecedented hydrogen evolution rate of 47.6 mmolh-1g 1 under visible-light, demonstrating- 48% enhancement comparing to the sample without slow photon effect. In particular, a 9.83% apparent quantum yield under 450 nm monochromatic light is achieved for TAC-10. A model is proposed and finite-difference time-domain (FDTD) simulations reveal the size influence of Au NPs in ternary TAC photocatalysts. This work suggests that the rational design of bifunctional Au NPs coupling with slow photon effect could largely promote hydrogen production from visible-light driven water splitting. (c) 2021 Elsevier Inc. 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 |
000704428600004 |
Publication Date |
2021-07-01 |
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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 |
0021-9797 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.233 |
Times cited |
|
Open Access |
Not_Open_Access |
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| |
Notes |
|
Approved |
Most recent IF: 4.233 |
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| |
Call Number |
UA @ admin @ c:irua:182531 |
Serial |
6886 |
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| Permanent link to this record |
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| |
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Author |
Lezaack, M.B.; Hannard, F.; Zhao, L.; Orekhov, A.; Adrien, J.; Miettinen, A.; Idrissi, H.; Simar, A. |
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| |
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 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
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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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 |
000718127100006 |
Publication Date |
2021-10-19 |
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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 |
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Series Issue |
|
Edition |
|
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| |
ISSN |
2589-1529 |
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 |
Not_Open_Access |
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| |
Notes |
|
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ admin @ c:irua:184145 |
Serial |
6894 |
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| Permanent link to this record |
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| |
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Author |
Ding, L.; Zhao, M.; Ehlers, F.J.H.; Jia, Z.; Zhang, Z.; Weng, Y.; Schryvers, D.; Liu, Q.; Idrissi, H. |
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| |
Title |
“Branched” structural transformation of the L12-Al3Zr phase manipulated by Cu substitution/segregation in the Al-Cu-Zr alloy system |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Journal of materials science & technology |
Abbreviated Journal |
Journal of Materials Science & Technology |
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| |
Volume |
185 |
Issue |
|
Pages |
186-206 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The effect of Cu on the evolution of the Al3Zr phase in an Al-Cu-Zr cast alloy during solution treatment at 500 °C has been thoroughly studied by combining atomic resolution high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy and first-principles cal- culations. The heat treatment initially produces a pure L12-Al3Zr microstructure, allowing for about 13 % Cu to be incorporated in the dispersoid. Cu incorporation increases the energy barrier for anti-phase boundary (APB) activation, thus stabilizing the L12 structure. Additional heating leads to a Cu-induced “branched”path for the L12 structural transformation, with the latter process accelerated once the first APB has been created. Cu atoms may either (i) be repelled by the APBs, promoting the transformation to a Cu-poor D023 phase, or (ii) they may segregate at one Al-Zr layer adjacent to the APB, promoting a transformation to a new thermodynamically favored phase, Al4CuZr, formed when these segregation layers are periodically arranged. Theoretical studies suggest that the branching of the L12 transformation path is linked to the speed at which an APB is created, with Cu attraction triggered by a comparatively slow process. This unexpected transformation behavior of the L12-Al3Zr phase opens a new path to understanding, and potentially regulating the Al3Zr dispersoid evolution for high temperature applications. |
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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 |
001154261100001 |
Publication Date |
2023-12-24 |
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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 |
1005-0302 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
10.9 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
This work was supported by the National Key Research and Development Program (No. 2020YFA0405900), the National Natural Science Foundation of China (Grant No. 52371111 and U2141215 ), the Natural Science Foundation of Jiangsu Province (No. BE2022159 ). We are grateful to the High Performance Computing Center of Nanjing Tech University for supporting the computational resources. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR- FNRS). |
Approved |
Most recent IF: 10.9; 2024 IF: 2.764 |
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| |
Call Number |
EMAT @ emat @c:irua:202392 |
Serial |
8981 |
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| Permanent link to this record |
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Author |
Windels, S.; Diefenhardt, T.; Jain, N.; Marquez, C.; Bals, S.; Schlummer, M.; De Vos, D.E. |
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| |
Title |
Catalytic upcycling of PVC waste-derived phthalate esters into safe, hydrogenated plasticizers |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Green chemistry : cutting-edge research for a greener sustainable future |
Abbreviated Journal |
Green Chem |
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| |
Volume |
24 |
Issue |
2 |
Pages |
754-766 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Recycling of end-of-life polyvinyl chloride (PVC) calls for solutions to deal with the vast amounts of harmful phthalate plasticizers that have historically been incorporated in PVC. Here, we report on the upcycling of such waste-extracted phthalate esters into analogues of the much safer diisononyl 1,2-cyclohexanedicarboxylate plasticizer (DINCH), via a catalytic one-pot (trans)esterification-hydrogenation process. For most of the virgin phthalates, Ru/Al2O3 is a highly effective hydrogenation catalyst, yielding >99% ring-hydrogenated products under mild reaction conditions (0.1 mol% Ru, 80 degrees C, 50 bar H-2). However, applying this reaction to PVC-extracted phthalates proved problematic, (1) as benzyl phthalates are hydrogenolyzed to benzoic acids that inhibit the Ru-catalyst, and (2) because impurities in the plasticizer extract (PVC, sulfur) further retard the hydrogenation. These complications were solved by coupling the hydrogenation to an in situ (trans)esterification with a higher alcohol, and by pretreating the extract with an activated carbon adsorbent. In this way, a real phthalate extract obtained from post-consumer PVC waste was eventually completely (>99%) hydrogenated to phthalate-free, cycloaliphatic plasticizers. |
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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 |
000726865200001 |
Publication Date |
2021-11-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
1463-9262; 1463-9270 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.8 |
Times cited |
8 |
Open Access |
Not_Open_Access |
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| |
Notes |
This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement no. 821366 (programma acronym: Circular Flooring). D. E. D. V. thanks FWO for project funding (SBO project S001819N Triple Cycle); N. J. and S. B. acknowledge the financial support from FWO and FNRS (EOS 30489208). Finally, the authors also thank S. Smolders for assistance with the TGA-MS experiments and D. Paredaens for his experimental contribution |
Approved |
Most recent IF: 9.8 |
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| |
Call Number |
UA @ admin @ c:irua:184746 |
Serial |
6958 |
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| Permanent link to this record |
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Author |
Meng, X.; Chen, S.; Peng, H.; Bai, H.; Zhang, S.; Su, X.; Tan, G.; Van Tendeloo, G.; Sun, Z.; Zhang, Q.; Tang, X.; Wu, J. |
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Title |
Ferroelectric engineering : enhanced thermoelectric performance by local structural heterogeneity |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Science China : materials |
Abbreviated Journal |
Sci China Mater |
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Volume |
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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 |
Although traditional ferroelectric materials are usually dielectric and nonconductive, GeTe is a typical ferroelectric semiconductor, possessing both ferroelectric and semiconducting properties. GeTe is also a widely studied thermoelectric material, whose performance has been optimized by doping with various elements. However, the impact of the ferroelectric domains on the thermoelectric properties remains unclear due to the difficulty to directly observe the ferroelectric domains and their evolutions under actual working conditions where the material is exposed to high temperatures and electric currents. Herein, based on in-situ investigations of the ferroelectric domains and domain walls in both pure and Sb-doped GeTe crystals, we have been able to analyze the dynamic evolution of the ferroelectric domains and domain walls, exposed to an electric field and temperature. Local structural heterogeneities and nano-sized ferroelectric domains are generated due to the interplay of the Sb3+ dopant and the Ge-vacancies, leading to the increased number of charged domain walls and a much improved thermoelectric performance. This work reveals the fundamental mechanism of ferroelectric thermoelectrics and provides insights into the decoupling of previously interdependent properties such as thermo-power and electrical conductivity. |
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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 |
000749973500001 |
Publication Date |
2022-02-02 |
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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 |
2095-8226; 2199-4501 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.1 |
Times cited |
|
Open Access |
Not_Open_Access |
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| |
Notes |
|
Approved |
Most recent IF: 8.1 |
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| |
Call Number |
UA @ admin @ c:irua:186429 |
Serial |
6959 |
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| Permanent link to this record |
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Author |
Lu, W.; Cui, W.; Zhao, W.; Lin, W.; Liu, C.; Van Tendeloo, G.; Sang, X.; Zhao, W.; Zhang, Q. |
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Title |
In situ atomistic insight into magnetic metal diffusion across Bi0.5Sb1.5Te3 quintuple layers |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
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Volume |
|
Issue |
|
Pages |
2102161 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Diffusion and occupancy of magnetic atoms in van der Waals (VDW) layered materials have significant impact on applications such as energy storage, thermoelectrics, catalysis, and topological phenomena. However, due to the weak VDW bonding, most research focus on in-plane diffusion within the VDW gap, while out-of-plane diffusion has rarely been reported. Here, to investigate out-of-plane diffusion in VDW-layered Bi2Te3-based alloys, a Ni/Bi0.5Sb1.5Te3 heterointerface is synthesized by depositing magnetic Ni metal on a mechanically exfoliated Bi0.5Sb1.5Te3 (0001) substrate. Diffusion of Ni atoms across the Bi0.5Sb1.5Te3 quintuple layers is directly observed at elevated temperatures using spherical-aberration-corrected scanning transmission electron microscopy (STEM). Density functional theory calculations demonstrate that the diffusion energy barrier of Ni atoms is only 0.31-0.45 eV when they diffuse through Te-3(Bi, Sb)(3) octahedron chains. Atomic-resolution in situ STEM reveals that the distortion of the Te-3(Bi, Sb)(3) octahedron, induced by the Ni occupancy, drives the formation of coherent NiM (M = Bi, Sb, Te) at the heterointerfaces. This work can lead to new strategies to design novel thermoelectric and topological materials by introducing magnetic dopants to VDW-layered materials. |
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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 |
000751742300001 |
Publication Date |
2022-02-07 |
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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 |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.4 |
Times cited |
|
Open Access |
Not_Open_Access |
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| |
Notes |
|
Approved |
Most recent IF: 5.4 |
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| |
Call Number |
UA @ admin @ c:irua:186421 |
Serial |
6960 |
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| Permanent link to this record |
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Author |
Li, W.; Tong, W.; Yadav, A.; Bladt, E.; Bals, S.; Funston, A.M.; Etheridge, J. |
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Title |
Shape control beyond the seeds in gold nanoparticles |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
33 |
Issue |
23 |
Pages |
9152-9164 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In typical seed-mediated syntheses of metal nanocrystals, the shape of the nanocrystal is determined largely by the seed nucleation environment and subsequent growth environment (where “environment” refers to the chemical environment, including the surfactant and additives). In this approach, crystallinity is typically determined by the seeds, and surfaces are controlled by the environment(s). However, surface energies, and crystallinity, are both influenced by the choice of environment(s). This limits the permutations of crystallinity and surface facets that can be mixed and matched to generate new nanocrystal morphologies. Here, we control post-seed growth to deliberately incorporate twin planes during the growth stage to deliver new final morphologies, including twinned cubes and bipyramids from single-crystal seeds. The nature and number of twin planes, together with surfactant control of facet growth, define the final nanoparticle morphology. Moreover, by breaking symmetry, the twin planes introduce new facet orientations. This additional mechanism opens new routes for the synthesis of different morphologies and facet orientations. |
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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 |
000753956100012 |
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 |
|
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 |
3 |
Open Access |
Not_Open_Access |
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| |
Notes |
This work was supported by the Australian Research Council (ARC) Grants DP160104679 and CE170100026 and used microscopes at the Monash Centre for Electron Microscopy funded by ARC Grants LE0454166, LE110100223, and LE140100104. W.L. thanks the support of the Australian Government Research Training Program (RTP) scholarship. W.T. thanks the Australian Department of Education and Monash University for the IPRS and APA scholarships. E.B. acknowledges financial support and a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). The authors thank Dr. Matthew Weyland and Dr. Tim Peterson for helpful discussions. A.Y. thanks the support from Post Graduation Publication Award (PPA) scholarship from Monash University. |
Approved |
Most recent IF: 9.466 |
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| |
Call Number |
UA @ admin @ c:irua:187229 |
Serial |
7065 |
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| Permanent link to this record |
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Author |
Canossa, S.; Ferrari, E.; Sippel, P.; Fischer, J.K.H.; Pfattner, R.; Frison, R.; Masino, M.; Mas-Torrent, M.; Lunkenheimer, P.; Rovira, C.; Girlando, A. |
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Title |
Tetramethylbenzidine-TetrafluoroTCNQ (TMB-TCNQF(4)) : a narrow-gap semiconducting salt with room-temperature relaxor ferroelectric behavior |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
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| |
Volume |
125 |
Issue |
46 |
Pages |
25816-25824 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We present an extension and revision of the spectroscopic and structural data of the mixed-stack charge-transfer (CT) crystal 3,3 ',5,5 '-tetramethylbenzidine-tetrafluorotetracyano-quinodimethane (TMB-TCNQF4), associated with new electric and dielectric measurements. Refinement of synchrotron structural data at low temperature has led to revise the previously reported C2/m structure. The revised structure is P2(1)/m, with two dimerized stacks per unit cell, and is consistent with the low temperature vibrational data. However, polarized Raman data in the low-frequency region also indicate that by increasing temperature above 200 K, the structure presents an increasing degree of disorder, mainly along the stack axis. X-ray diffraction data at room temperature have confirmed that the correct structure is P2(1)/ m -no phase transitions -but did not allow substantiating the presence of disorder. On the other hand, dielectric measurements have evidenced a typical relaxor ferroelectric behavior already at room temperature, with a peak in the real part of dielectric constant epsilon'(T,v) around 200 K and 0.1 Hz. The relaxor behavior is explained in terms of the presence of spin solitons separating domains of opposite polarity that yield to ferroelectric nanodomains. TMB-TCNQF(4) is confirmed to be a narrow-gap band semiconductor (Ea similar to 0.3 eV) with a room-temperature conductivity of similar to 10(-4) Omega(-1) cm(-1). |
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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 |
000731170500008 |
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 |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.536 |
Times cited |
|
Open Access |
Not_Open_Access |
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| |
Notes |
A.G. thanks Prof. Pascale Foury-Leylekian for very helpful discussions about the crystallographic issues. R.F. thanks Prof. Anthony Linden for his help in the X-ray diffraction data collection. J.K.H.F. and P.L. acknowledge funding from the Deutsche Forschungsgemeinschaft (DFG) via the Transregional Collaborative Research Center TRR80 (Augsburg, Munich). R.P. and M.M.-T. acknowledge support from the Marie Curie Cofund, Beatriu de Pinós Fellowships (Grant nos. AGAUR 2017 BP 00064). This work was also supported by the Spanish Ministry project GENESIS PID2019-111682RBI00, the “Severo Ochoa” Programme for Centers of Excellence in R&D (FUNFUTURE, CEX2019-000917-S), and the Generalitat de Catalunya (2017-SGR-918). The Elettra Synchrotron (CNR Trieste) is acknowledged for granting the beamtime at the single-crystal diffraction beamline XRD1 (Proposal ID 20185483). In Parma, the work has benefited from the equipment and support of the COMP-HUB Initiative, funded by the “Departments of Excellence” program of the |
Approved |
Most recent IF: 4.536 |
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| |
Call Number |
UA @ admin @ c:irua:184866 |
Serial |
7066 |
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| Permanent link to this record |
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Author |
Savina, A.A.; Saiutina, V.V.; Morozov, A.V.; Boev, A.O.; Aksyonov, D.A.; Dejoie, C.; Batuk, M.; Bals, S.; Hadermann, J.; Abakumov, A.M. |
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Title |
Chemistry, local molybdenum clustering, and electrochemistry in the Li2+xMo1-xO3 solid solutions |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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| |
Volume |
61 |
Issue |
14 |
Pages |
5637-5652 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A broad range of cationic nonstoichiometry has been demonstratedfor the Li-rich layered rock-salt-type oxide Li2MoO3, which has generally been considered as a phase with a well-defined chemical composition. Li2+xMo1-xO3(-0.037 <= x <= 0.124) solid solutions were synthesized via hydrogen reduction ofLi2MoO4in the temperature range of 650-1100 degrees C, withxdecreasing with theincrease of the reduction temperature. The solid solutions adopt a monoclinicallydistorted O3-type layered average structure and demonstrate a robust localordering of the Li cations and Mo3triangular clusters within the mixed Li/Mocationic layers. The local structure was scrutinized in detail by electron diffractionand aberration-corrected scanning transmission electron microcopy (STEM),resulting in an ordering model comprising a uniform distribution of the Mo3clusters compatible with local electroneutrality and chemical composition. The geometry of the triangular clusters with their oxygenenvironment (Mo3O13groups) has been directly visualized using differential phase contrast STEM imaging. The established localstructure was used as input for density functional theory (DFT)-based calculations; they support the proposed atomic arrangementand provide a plausible explanation for the staircase galvanostatic charge profiles upon electrochemical Li+extraction fromLi2+xMo1-xO3in Li cells. According to DFT, all electrochemical capacity in Li2+xMo1-xO3solely originates from the cationic Moredox process, which proceeds via oxidation of the Mo3triangular clusters into bent Mo3chains where the electronic capacity of the clusters depends on the initial chemical composition and Mo oxidation state defining the width of the first charge low-voltageplateau. Further oxidation at the high-voltage plateau proceeds through decomposition of the Mo3chains into Mo2dimers and further into individual Mo6+cations |
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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 |
000789034200023 |
Publication Date |
2022-04-01 |
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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 |
0020-1669 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.6 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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Notes |
The authors acknowledge Russian Science Foundation (grant 20-43-01012) and Research Foundation Flanders (FWO Vlaanderen, project number G0F1320N) for financial support. The authors are grateful to AICF of Skoltech for providing access to electron microscopy equipment. The authors are grateful to Prof. G. Van Tendeloo for discussing the results. |
Approved |
Most recent IF: 4.6 |
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| |
Call Number |
UA @ admin @ c:irua:188631 |
Serial |
7079 |
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| Permanent link to this record |
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Author |
Poulain, R.; Lumbeeck, G.; Hunka, J.; Proost, J.; Savolainen, H.; Idrissi, H.; Schryvers, D.; Gauquelin, N.; Klein, A. |
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Title |
Electronic and chemical properties of nickel oxide thin films and the intrinsic defects compensation mechanism |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
ACS applied electronic materials |
Abbreviated Journal |
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| |
Volume |
4 |
Issue |
6 |
Pages |
2718-2728 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Although largely studied, contradictory results on nickel oxide (NiO) properties can be found in the literature. We herein propose a comprehensive study that aims at leveling contradictions related to NiO materials with a focus on its conductivity, surface properties, and the intrinsic charge defects compensation mechanism with regards to the conditions preparation. The experiments were performed by in situ photo-electron spectroscopy, electron energy loss spectroscopy, and optical as well as electrical measurements on polycrystalline NiO thin films prepared under various preparation conditions by reactive sputtering. The results show that surface and bulk properties were strongly related to the deposition temperature with in particular the observation of Fermi level pinning, high work function, and unstable oxygen-rich grain boundaries for the thin films produced at room temperature but not at high temperature (>200 degrees C). Finally, this study provides substantial information about surface and bulk NiO properties enabling to unveil the origin of the high electrical conductivity of room temperature NiO thin films and also for supporting a general electronic charge compensation mechanism of intrinsic defects according to the deposition temperature. |
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Place of Publication |
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Wos |
000819431200001 |
Publication Date |
2022-06-07 |
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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 |
2637-6113 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:189555 |
Serial |
7081 |
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| Permanent link to this record |
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Author |
Vishwakarma, M.; Batra, Y.; Hadermann, J.; Singh, A.; Ghosh, A.; Mehta, B.R. |
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Title |
Exploring the role of graphene oxide as a co-catalyst in the CZTS photocathodes for improved photoelectrochemical properties |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
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| |
Volume |
5 |
Issue |
6 |
Pages |
7538-7549 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The hydrogen evolution properties of CZTS heterostructure photocathodes are reported with graphene oxide (GO) as a co-catalyst layer coated by a drop-cast method and an Al2O3 protection layer fabricated using atomic layer deposition. In the CZTS absorber, a minor deviation from stoichiometry across the cross section of the thin film results in nanoscale growth of spurious phases, but the kesterite phase remains the dominant phase. We have investigated the band alignment parameters such as the band gap, work function, and Fermi level position that are crucial for making kesterite-based heterostructure devices. The photocurrent density in the photocathode CZTS/CdS/ZnO is found to be improved to -4.71 mAmiddotcm(-2) at -0.40 V-RHE, which is 3 times that of the pure CZTS. This enhanced photoresponse can be attributed to faster carrier separation at p-n junction regions driven by upward band bending at CZTS grain boundaries and the ZnO layer. GO as a co-catalyst over the heterostructure photocathode significantly improves the photocurrent density to -6.14 mAmiddotcm(-2) at -0.40 V-RHE by effective charge migration in the CZTS/CdS/ZnO/GO configuration, but the onset potential shifts only after application of the Al2O3 protection layer. Significant photocurrents of -29 mAmiddotcm(-2) at -0.40 V-RHE and -8 mAmiddotcm(-2) at 0 V-RHE are observed, with an onset potential of 0.7 V-RHE in CZTS/CdS/ZnO/GO/Al2O3. The heterostructure configuration and the GO co-catalyst reduce the charge-transfer resistance, while the Al2O3 top layer provides a stable photocurrent for a prolonged time (similar to 16 h). The GO co-catalyst increases the flat band potential from 0.26 to 0.46 V-RHE in CZTS/CdS/ZnO/GO, which supports the bias-induced band bending at the electrolyte-electrode interface. |
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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 |
000820418400001 |
Publication Date |
2022-05-24 |
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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 |
2574-0962 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.4 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
|
Approved |
Most recent IF: 6.4 |
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Call Number |
UA @ admin @ c:irua:189666 |
Serial |
7082 |
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| Permanent link to this record |
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Author |
Hao, Y.; Velpula, G.; Kaltenegger, M.; Bodlos, W.R.; Vibert, F.; Mali, K.S.; De Feyter, S.; Resel, R.; Geerts, Y.H.; Van Aert, S.; Beljonne, D.; Lazzaroni, R. |
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Title |
From 2D to 3D : bridging self-assembled monolayers to a substrate-induced polymorph in a molecular semiconductor |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
34 |
Issue |
5 |
Pages |
2238-2248 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In this study, a new bottom-up approach is proposed to predict the crystal structure of the substrate-induced polymorph (SIP) of an archetypal molecular semiconductor. In spite of intense efforts, the formation mechanism of SIPs is still not fully understood, and predicting their crystal structure is a very delicate task. Here, we selected lead phthalocyanine (PbPc) as a prototypical molecular material because it is a highly symmetrical yet nonplanar molecule and we demonstrate that the growth and crystal structure of the PbPc SIPs can be templated by the corresponding physisorbed self-assembled molecular networks (SAMNs). Starting from SAMNs of PbPc formed at the solution/graphite interface, the structural and energetic aspects of the assembly were studied by a combination of in situ scanning tunneling microscopy and multiscale computational chemistry approach. Then, the growth of a PbPc SIP on top of the physisorbed monolayer was modeled without prior experimental knowledge, from which the crystal structure of the SIP was predicted. The theoretical prediction of the SIP was verified by determining the crystal structure of PbPc thin films using X-ray diffraction techniques, revealing the formation of a new polymorph of PbPc on the graphite substrate. This study clearly illustrates the correlation between the SAMNs and SIPs, which are traditionally considered as two separate but conceptually connected research areas. This approach is applicable to molecular materials in general to predict the crystal structure of their SIPs. |
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Corporate Author |
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Place of Publication |
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Wos |
000812125800001 |
Publication Date |
2022-02-17 |
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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 |
0897-4756; 1520-5002 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.6 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 8.6 |
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Call Number |
UA @ admin @ c:irua:189086 |
Serial |
7084 |
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| Permanent link to this record |
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Author |
Hofer, C.; Gao, C.; Chennit, T.; Yuan, B.; Pennycook, T.J. |
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Title |
Phase offset method of ptychographic contrast reversal correction |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
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Issue |
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Pages |
113922 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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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 |
001164447000001 |
Publication Date |
2024-01-08 |
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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 |
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Impact Factor |
2.2 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
FWO, G013122N ; Horizon 2020 Framework Programme; European Research Council, 802123-HDEM ; European Research Council; |
Approved |
Most recent IF: 2.2; 2024 IF: 2.843 |
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Call Number |
EMAT @ emat @c:irua:202379 |
Serial |
8988 |
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Author |
Mary Joy, R.; Pobedinskas, P.; Baule, N.; Bai, S.; Jannis, D.; Gauquelin, N.; Pinault-Thaury, M.-A.; Jomard, F.; Sankaran, K.J.; Rouzbahani, R.; Lloret, F.; Desta, D.; D’Haen, J.; Verbeeck, J.; Becker, M.F.; Haenen, K. |
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Title |
The effect of microstructure and film composition on the mechanical properties of linear antenna CVD diamond thin films |
Type |
A1 Journal Article |
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Year |
2024 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Materialia |
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Volume |
264 |
Issue |
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Pages |
119548 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
This study reports the impact of film microstructure and composition on the Young’s modulus and residual stress in nanocrystalline diamond (NCD) thin films ( thick) grown on silicon substrates using a linear antenna microwave plasma-enhanced chemical vapor deposition (CVD) system. Combining laser acoustic wave spectroscopy to determine the elastic properties with simple wafer curvature measurements, a straightforward method to determine the intrinsic stress in NCD films is presented. Two deposition parameters are varied: (1) the substrate temperature from 400 °C to 900 °C, and (2) the [P]/[C] ratio from 0 ppm to 8090 ppm in the H2/CH4/CO2/PH3 diamond CVD plasma. The introduction of PH3 induces a transition in the morphology of the diamond film, shifting from NCD with larger grains to ultra-NCD with a smaller grain size, concurrently resulting in a decrease in Young’s modulus. Results show that the highest Young’s modulus of (113050) GPa for the undoped NCD deposited at 800 °C is comparable to single crystal diamond, indicating that NCD with excellent mechanical properties is achievable with our process for thin diamond films. Based on the film stress results, we propose the origins of tensile intrinsic stress in the diamond films. In NCD, the tensile intrinsic stress is attributed to larger grain size, while in ultra-NCD films the tensile intrinsic stress is due to grain boundaries and impurities. |
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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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Language |
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Wos |
001126632800001 |
Publication Date |
2023-11-23 |
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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 |
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ISSN |
1359-6454 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.4 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
This work was financially supported by the Special Research Fund (BOF) via Methusalem NANO network, the Research Foundation – Flanders (FWO) via Project G0D4920N, and the CORNET project nr 263-EN “ULTRAHARD: Ultrahard optical diamond coatings” (2020–2021). |
Approved |
Most recent IF: 9.4; 2024 IF: 5.301 |
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Call Number |
EMAT @ emat @c:irua:202169 |
Serial |
8989 |
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Author |
Hendrickx, M.; Paulus, A.; Kirsanova, M.A.; Van Bael, M.K.; Abakumov, A.M.; Hardy, A.; Hadermann, J. |
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Title |
The influence of synthesis method on the local structure and electrochemical properties of Li-rich/Mn-rich NMC cathode materials for Li-Ion batteries |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Nanomaterials |
Abbreviated Journal |
Nanomaterials-Basel |
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Volume |
12 |
Issue |
13 |
Pages |
2269-18 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Electrochemical energy storage plays a vital role in combating global climate change. Nowadays lithium-ion battery technology remains the most prominent technology for rechargeable batteries. A key performance-limiting factor of lithium-ion batteries is the active material of the positive electrode (cathode). Lithium- and manganese-rich nickel manganese cobalt oxide (LMR-NMC) cathode materials for Li-ion batteries are extensively investigated due to their high specific discharge capacities (>280 mAh/g). However, these materials are prone to severe capacity and voltage fade, which deteriorates the electrochemical performance. Capacity and voltage fade are strongly correlated with the particle morphology and nano- and microstructure of LMR-NMCs. By selecting an adequate synthesis strategy, the particle morphology and structure can be controlled, as such steering the electrochemical properties. In this manuscript we comparatively assessed the morphology and nanostructure of LMR-NMC (Li1.2Ni0.13Mn0.54Co0.13O2) prepared via an environmentally friendly aqueous solution-gel and co-precipitation route, respectively. The solution-gel (SG) synthesized material shows a Ni-enriched spinel-type surface layer at the {200} facets, which, based on our post-mortem high-angle annual dark-field scanning transmission electron microscopy and selected-area electron diffraction analysis, could partly explain the retarded voltage fade compared to the co-precipitation (CP) synthesized material. In addition, deviations in voltage fade and capacity fade (the latter being larger for the SG material) could also be correlated with the different particle morphology obtained for both materials. |
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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 |
000824547500001 |
Publication Date |
2022-07-01 |
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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 |
2079-4991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.3 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
|
Approved |
Most recent IF: 5.3 |
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Call Number |
UA @ admin @ c:irua:189591 |
Serial |
7098 |
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| Permanent link to this record |
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Author |
Arseenko, M.; Hannard, F.; Ding, L.; Zhao, L.; Maire, E.; Villanova, J.; Idrissi, H.; Simar, A. |
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Title |
A new healing strategy for metals : programmed damage and repair |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
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Volume |
238 |
Issue |
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Pages |
118241-10 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Self-healing strategies aim at avoiding part repair or even replacement, which is time consuming, expen-sive and generates waste. However, strategies for metallic systems are still under-developed and solid-state solutions for room temperature service are limited to nano-scale damage repair. Here we propose a new healing strategy of micron-sized damage requiring only short and low temperature heating. This new strategy is based on damage localization particles, which can be healed by fast diffusing atoms of the matrix activated during heat treatment. The healing concept was successfully validated with a com-mercial aluminum alloy and manufactured by Friction Stir Processing (FSP). Damage was demonstrated to initiate on particles that were added to the matrix during material processing. In situ 2D and 3D nano -imaging confirmed healing of the damaged material and showed that heating this material for 10 min at 400 degrees C is sufficient to heal incipient damage with complete filling of 70% of all damage (and up to 90% when their initial size is below 0.2 mu m). Furthermore, strength is retained and the work of fracture of the alloy is improved by about 40% after healing. The proposed Programmed Damage and Repair healing strategy could be extended to other metal based systems presenting precipitation. (C) 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
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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 |
000843502700006 |
Publication Date |
2022-08-03 |
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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 |
1359-6454 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.4 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 9.4 |
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Call Number |
UA @ admin @ c:irua:190561 |
Serial |
7121 |
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| Permanent link to this record |
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Author |
Frolov, A.S.; Callaert, C.; Batuk, M.; Hadermann, J.; Volykhov, A.A.; Sirotina, A.P.; Amati, M.; Gregoratti, L.; Yashina, L.V. |
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Title |
Nanoscale phase separation in the oxide layer at GeTe (111) surfaces |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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Volume |
14 |
Issue |
35 |
Pages |
12918-12927 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
As a semiconductor ferroelectric, GeTe has become a focus of renewed attention due to the recent discovery of giant Rashba splitting. It already has a wide range of applications, from thermoelectricity to data storage. Its stability in ambient air, as well as the structure and properties of an oxide layer, define the processing media for device production and operation. Here, we studied a reaction between the GeTe (111) surface and molecular oxygen for crystals having solely inversion domains. We evaluated the reaction kinetics both ex situ and in situ using NAP XPS. The structure of the oxide layer is extensively discussed, where, according to HAADF-STEM and STEM-EDX, nanoscale phase separation of GeO2 and Te is observed, which is unusual for semiconductors. We believe that such behaviour is closely related to the ferroelectric properties and the domain structure of GeTe. |
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Corporate Author |
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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 |
000847743300001 |
Publication Date |
2022-08-25 |
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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 |
2040-3364; 2040-3372 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
6.7 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 6.7 |
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Call Number |
UA @ admin @ c:irua:190665 |
Serial |
7181 |
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Author |
Guo, A.; Bai, H.; Liang, Q.; Feng, L.; Su, X.; Van Tendeloo, G.; Wu, J. |
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Title |
Resistive switching in Ag₂Te semiconductor modulated by Ag+-ion diffusion and phase transition |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Advanced Electronic Materials |
Abbreviated Journal |
Adv Electron Mater |
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Volume |
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Issue |
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Pages |
2200850-2200858 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Memristors are considered to be the fourth circuit element and have great potential in areas like logic operations, information storage, and neuromorphic computing. The functional material in a memristor, which has a nonlinear resistance, is the key component to be developed. Herein, resistive switching is demonstrated and the structural evolutions in Ag2Te are examined under an external electric field. It is shown that the electroresistance effect is originating from an electronically triggered phase transition together with directional Ag+-ion diffusion. Using in situ transmission electron microscopy, the phase transition from the monoclinic alpha-Ag2Te into the face-centered cubic beta-Ag2Te, accompanied by a change in resistance, is directly observed. Diffusion of Ag+-ions modulates the localized density of Ag+-ion vacancies, leading to a change in electrical conductivity and influences the threshold voltage to trigger the phase transition. During the electric field-driven phase transition, the spontaneous and localized multiple polarizations from the low-symmetry alpha-Ag2Te (referring to an antiferroelectric structure) are vanishing in the cubic beta-Ag2Te (referring to a paraelectric structure). The abrupt resistance change of thin Ag2Te caused by the phase transition and modulated by the applied electric field demonstrates its great potential as functional material in volatile memory and memristors with a low-energy consumption. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Wos |
000855728500001 |
Publication Date |
2022-09-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2199-160x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.2 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 6.2 |
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Call Number |
UA @ admin @ c:irua:190582 |
Serial |
7203 |
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Author |
Zeegers, M.T.; Kadu, A.; van Leeuwen, T.; Batenburg, K.J. |
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Title |
ADJUST : a dictionary-based joint reconstruction and unmixing method for spectral tomography |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Inverse problems |
Abbreviated Journal |
Inverse Probl |
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Volume |
38 |
Issue |
12 |
Pages |
125002-125033 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Advances in multi-spectral detectors are causing a paradigm shift in x-ray computed tomography (CT). Spectral information acquired from these detectors can be used to extract volumetric material composition maps of the object of interest. If the materials and their spectral responses are known a priori, the image reconstruction step is rather straightforward. If they are not known, however, the maps as well as the responses need to be estimated jointly. A conventional workflow in spectral CT involves performing volume reconstruction followed by material decomposition, or vice versa. However, these methods inherently suffer from the ill-posedness of the joint reconstruction problem. To resolve this issue, we propose 'A Dictionary-based Joint reconstruction and Unmixing method for Spectral Tomography' (ADJUST). Our formulation relies on forming a dictionary of spectral signatures of materials common in CT and prior knowledge of the number of materials present in an object. In particular, we decompose the spectral volume linearly in terms of spatial material maps, a spectral dictionary, and the indicator of materials for the dictionary elements. We propose a memory-efficient accelerated alternating proximal gradient method to find an approximate solution to the resulting bi-convex problem. From numerical demonstrations on several synthetic phantoms, we observe that ADJUST performs exceedingly well compared to other state-of-the-art methods. Additionally, we address the robustness of ADJUST against limited and noisy measurement patterns. The demonstration of the proposed approach on a spectral micro-CT dataset shows its potential for real-world applications. Code is available at https://github.com/mzeegers/ADJUST. |
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Thesis |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000868885200001 |
Publication Date |
2022-09-20 |
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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 |
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Series Issue |
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Edition |
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ISSN |
0266-5611 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.1 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 2.1 |
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Call Number |
UA @ admin @ c:irua:191536 |
Serial |
7280 |
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Author |
Morsdorf, L.; Kashiwar, A.; Kübel, C.; Tasan, C.C. |
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Title |
Carbon segregation and cementite precipitation at grain boundaries in quenched and tempered lath martensite |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
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Volume |
862 |
Issue |
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Pages |
144369-21 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Tempering is widely applied to make carbon atoms beneficially rearrange in high strength steel microstructures after quenching; though the nano-scale interaction of carbon atoms with crystallographic defects is hard to experimentally observe. To improve, we investigate the redistribution of carbon atoms along martensite grain boundaries in a quenched and tempered low carbon steel. We observe the tempering-induced microstructural evolution by in-situ heating in a transmission electron microscope (TEM) and by compositional analysis through atom probe tomography (APT). Probe volumes for APT originate from a single martensite packet but in different tempering conditions, which is achieved via a sequential lift-out with in-between tempering treatments. The complementary use of TEM and APT provides crystallographic as well as chemical information on carbon segregation and subsequent carbide precipitation at martensite grain boundaries. The results show that the amount of carbon segregation to martensite grain boundaries is influenced by the boundary type, e.g. low-angle lath or high-angle block boundaries. Also, the growth behavior of cementite precipitates from grain boundary nucleation sites into neighboring martensite grains differs at low- and high-angle grain boundaries. This is due to the crystallographic constraints arising from the semi-coherent orientation relationship between cementite and adjacent martensite. We also show that slower quenching stabilizes thin retained austenite films between martensite grains because of enhanced carbon segregation during cooling. Finally, we demonstrate the effect of carbon redistribution along martensite grain boundaries on the mechanical properties. Here, we compare micro-scale Vickers hardness results from boundary-containing probe volumes to nanoindentation results from pure bulk martensite (boundary-free) probe volumes. |
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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 |
000905165700001 |
Publication Date |
2022-12-07 |
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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 |
0921-5093 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.4 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 6.4; 2023 IF: 3.094 |
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Call Number |
UA @ admin @ c:irua:192279 |
Serial |
7285 |
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| Permanent link to this record |
