| |
Records |
Links |
|
Author |
Bigiani, L.; Gasparotto, A.; Maccato, C.; Sada, C.; Verbeeck, J.; Andreu, T.; Morante, J.R.; Barreca, D. |
|
| |
Title |
Dual improvement of beta-MnO₂ oxygen evolution electrocatalysts via combined substrate control and surface engineering |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Chemcatchem |
Abbreviated Journal |
Chemcatchem |
|
| |
Volume |
|
Issue |
|
Pages |
1-10 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The development of catalysts with high intrinsic activity towards the oxygen evolution reaction (OER) plays a critical role in sustainable energy conversion and storage. Herein, we report on the development of efficient (photo)electrocatalysts based on functionalized MnO(2)systems. Specifically,beta-MnO(2)nanostructures grown by plasma enhanced-chemical vapor deposition on fluorine-doped tin oxide (FTO) or Ni foams were decorated with Co(3)O(4)or Fe(2)O(3)nanoparticles by radio frequency sputtering. Upon functionalization, FTO-supported materials yielded a performance increase with respect to bare MnO2, with current densities at 1.65 Vvs. the reversible hydrogen electrode (RHE) up to 3.0 and 3.5 mA/cm(2)in the dark and under simulated sunlight, respectively. On the other hand, the use of highly porous and conductive Ni foam substrates enabled to maximize cooperative interfacial effects between catalyst components. The best performing Fe2O3/MnO(2)system provided a current density of 17.9 mA/cm(2)at 1.65 Vvs. RHE, an overpotential as low as 390 mV, and a Tafel slope of 69 mV/decade under dark conditions, comparing favorably with IrO(2)and RuO(2)benchmarks. Overall, the control of beta-MnO2/substrate interactions and the simultaneous surface property engineering pave the way to an efficient energy generation from abundant natural resources. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000571229000001 |
Publication Date |
2020-09-18 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1867-3880; 1867-3899 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.5 |
Times cited |
5 |
Open Access  |
Not_Open_Access |
|
| |
Notes |
; This work has been financially supported by Padova University DOR 2017-2019, P-DiSC #03BIRD2016-UNIPD and #03BIRD2018-UNIPD projects. A.G. acknowledges AMGA Foundation and INSTM Consortium. J.V. gratefully acknowledges funding from the GOA project “Solarpaint” of the University of Antwerp and the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717-ESTEEM3. ; esteem3TA; esteem3reported |
Approved |
Most recent IF: 4.5; 2020 IF: 4.803 |
|
| |
Call Number |
UA @ admin @ c:irua:171949 |
Serial |
6493 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Delvaux, A.; Lumbeeck, G.; Idrissi, H.; Proost, J. |
|
| |
Title |
Effect of microstructure and internal stress on hydrogen absorption into Ni thin film electrodes during alkaline water electrolysis |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Electrochimica Acta |
Abbreviated Journal |
Electrochim Acta |
|
| |
Volume |
340 |
Issue |
|
Pages |
135970-10 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Efforts to improve the cell efficiency of hydrogen production by water electrolysis continue to address the electrochemical kinetics of the oxygen and hydrogen evolution reactions in detail. The objective of this work is to study a parasitic reaction occurring during the hydrogen evolution reaction (HER), namely the absorption of hydrogen atoms into the bulk electrode. Effects of the electrode microstructure and internal stress on this reaction have been addressed as well in this paper. Ni thin film samples were deposited on a Si substrate by sputter deposition with different deposition pressures, resulting in different microstructures and varying levels of internal stress. These microstructures were first analyzed in detail by Transmission Electron Microscopy (TEM). Cathodic chrono-amperometric measurements and cyclic voltammetries have then been performed in a homemade electrochemical cell. These tests were coupled to a multi-beam optical sensor (MOS) in order to obtain in-situ curvature measurements during hydrogen absorption. Indeed, since hydrogen absorption in the thin film geometry results in a constrained volume expansion, internal stress generation during HER can be monitored by means of curvature measurements. Our results show that different levels of internal stress, grain size and twin boundary density can be obtained by varying the deposition parameters. From an electrochemical point of view, this paper highlights the fact that the electrochemical surface mechanisms during HER are the same for all the electrodes, regardless of their microstructure. However it is shown that the absolute amount of hydrogen being absorbed into the Ni thin films increases when the grain size is reduced, due to a higher grain boundaries density which are favourite absorption sites for hydrogen. At the same time, it was concluded that H-2 evolution is favoured at electrodes having a more compressive (i.e. a less tensile) internal stress. Finally, the subtle effect of microstructure on the hydrogen absorption rate will be discussed as well. (C) 2020 Elsevier Ltd. All rights reserved. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000521531800011 |
Publication Date |
2020-02-26 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0013-4686 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.6 |
Times cited |
2 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; The authors gratefully acknowledge financial support of the Public Service of Wallonia e Department of Energy and Sustainable Building, through the project WallonHY. The ACOM-TEM work was supported by the Hercules Foundation [Grant No. AUHA13009], the Flemish Research Fund (FWO) [Grant No. G.0365.15 N], and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. We also like to cordially thank Ronny Santoro for carrying out the ICP-OES measurements. ; |
Approved |
Most recent IF: 6.6; 2020 IF: 4.798 |
|
| |
Call Number |
UA @ admin @ c:irua:168536 |
Serial |
6497 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Mao, J.; Milovanović, S.P.; Andelkovic, M.; Lai, X.; Cao, Y.; Watanabe, K.; Taniguchi, T.; Covaci, L.; Peeters, F.M.; Geim, A.K.; Jiang, Y.; Andrei, E.Y. |
|
| |
Title |
Evidence of flat bands and correlated states in buckled graphene superlattices |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Nature |
Abbreviated Journal |
Nature |
|
| |
Volume |
584 |
Issue |
7820 |
Pages |
215-220 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
| |
Abstract |
Two-dimensional atomic crystals can radically change their properties in response to external influences, such as substrate orientation or strain, forming materials with novel electronic structure(1-5). An example is the creation of weakly dispersive, 'flat' bands in bilayer graphene for certain 'magic' angles of twist between the orientations of the two layers(6). The quenched kinetic energy in these flat bands promotes electron-electron interactions and facilitates the emergence of strongly correlated phases, such as superconductivity and correlated insulators. However, the very accurate fine-tuning required to obtain the magic angle in twisted-bilayer graphene poses challenges to fabrication and scalability. Here we present an alternative route to creating flat bands that does not involve fine-tuning. Using scanning tunnelling microscopy and spectroscopy, together with numerical simulations, we demonstrate that graphene monolayers placed on an atomically flat substrate can be forced to undergo a buckling transition(7-9), resulting in a periodically modulated pseudo-magnetic field(10-14), which in turn creates a 'post-graphene' material with flat electronic bands. When we introduce the Fermi level into these flat bands using electrostatic doping, we observe a pseudogap-like depletion in the density of states, which signals the emergence of a correlated state(15-17). This buckling of two-dimensional crystals offers a strategy for creating other superlattice systems and, in particular, for exploring interaction phenomena characteristic of flat bands. Buckled monolayer graphene superlattices are found to provide an alternative to twisted bilayer graphene for the study of flat bands and correlated states in a carbon-based material. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000559831500012 |
Publication Date |
2020-08-12 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0028-0836 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
64.8 |
Times cited |
75 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 64.8; 2020 IF: 40.137 |
|
| |
Call Number |
UA @ admin @ c:irua:171150 |
Serial |
6513 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Jin, B.; Zuo, N.; Hu, Z.-Y.; Cui, W.; Wang, R.; Van Tendeloo, G.; Zhou, X.; Zhai, T. |
|
| |
Title |
Excellent excitonic photovoltaic effect in 2D CsPbBr₃/CdS heterostructures |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
|
| |
Volume |
|
Issue |
|
Pages |
2006166-2006168 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
P-n photovoltaic junctions are essential building blocks for optoelectronic devices for energy conversion. However, this photovoltaic efficiency has almost reached its theoretical limit. Here, a brand-new excitonic photovoltaic effect in 2D CsPbBr3/CdS heterostructures is revealed. These heterostructures, synthesized by epitaxial growth, display a clean interface and a strong interlayer coupling. The excitonic photovoltaic effect is a function of both the built-in equilibrium electrical potential energy and the chemical potential energy, which is generated by the significant concentration gradient of electrons and holes at the heterojunction interface. Excitingly, this novel photovoltaic effect results in a large open-circuit voltage of 0.76 V and a high power conversion efficiency of 17.5%. In addition, high photodetection performance, including a high photoswitch ratio (I-light/I-dark) of 10(5)and a fast response rate of 23 mu s are obtained. These findings provide a new platform for photovoltaic applications. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000567829000001 |
Publication Date |
2020-09-21 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
19 |
Times cited |
1 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; B.J., N.Z., and Z.Y.H. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (Grant No. 21825103 and 51802103), the Hubei Provincial Natural Science Foundation of China (Grant No. 2019CFA002), and the Fundamental Research Funds for the Central University (Grant No. 2019kfyXMBZ018, WUT: 2019III012GX). Here the authors also thank the support from Analytical and Testing Center in HUST and the State Key Laboratory of Silicate Materials for Architectures in WUT. ; |
Approved |
Most recent IF: 19; 2020 IF: 12.124 |
|
| |
Call Number |
UA @ admin @ c:irua:171970 |
Serial |
6514 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Sun, C.; Liao, X.; Xia, F.; Zhao, Y.; Zhang, L.; Mu, S.; Shi, S.; Li, Y.; Peng, H.; Van Tendeloo, G.; Zhao, K.; Wu, J. |
|
| |
Title |
High-voltage cycling induced thermal vulnerability in LiCoO₂ cathode : cation loss and oxygen release driven by oxygen vacancy migration |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
|
| |
Volume |
14 |
Issue |
5 |
Pages |
6181-6190 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The release of the lattice oxygen due to the thermal degradation of layered lithium transition metal oxides is one of the major safety concerns in Li-ion batteries. The oxygen release is generally attributed to the phase transitions from the layered structure to spinel and rocksalt structures that contain less lattice oxygen. Here, a different degradation pathway in LiCoO2 is found, through oxygen vacancy facilitated cation migration and reduction. This process leaves undercoordinated oxygen that gives rise to oxygen release while the structure integrity of the defect-free region is mostly preserved. This oxygen release mechanism can be called surface degradation due to the kinetic control of the cation migration but has a slow surface to bulk propagation with continuous loss of the surface cation ions. It is also strongly correlated with the high-voltage cycling defects that end up with a significant local oxygen release at low temperatures. This work unveils the thermal vulnerability of high-voltage Li-ion batteries and the critical role of the surface fraction as a general mitigating approach. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000537682300101 |
Publication Date |
2020-04-17 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
17.1 |
Times cited |
8 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; C.S., X.L., and F.X. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (21905169). The S/TEM work was performed at the Nanostructure Research Center (NRC), which is supported by the Fundamental Research Funds for the Central Universities (WUT: 2019III012GX), the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, and the State Key Laboratory of Silicate Materials for Architectures (all of the laboratories are at Wuhan University of Technology). ; |
Approved |
Most recent IF: 17.1; 2020 IF: 13.942 |
|
| |
Call Number |
UA @ admin @ c:irua:170246 |
Serial |
6537 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Zhao, Z.X.; Ma, X.; Cao, S.; Li, Y.Y.; Zeng, C.Y.; Wang, D.X.; Yao, X.; Deng, Z.J.; Zhang, X.P. |
|
| |
Title |
Identification of nano-width variants in a fully monoclinic martensitic Ni50Ti50 alloy by scanning electron microscope-based transmission Kikuchi diffraction and improved groupoid structure approach |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Materials Letters |
Abbreviated Journal |
Mater Lett |
|
| |
Volume |
281 |
Issue |
|
Pages |
128624 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Nano-width martensite plates in a fully martensitic Ni50Ti50 alloy are indexed successfully by using the off-axis transmission Kikuchi diffraction in scanning electron microscope (i.e., SEM-based TKD). The data obtained by SEM-TKD are effectively interpreted using an improved approach based on the framework of the theoretical groupoid structure method, where the equivalent variants transformed from the monoclinic variants are introduced to calculate all theoretical axis/angle pairs of rotation, and to formulate a complete list of source martensite to target martensite pairs. Consequently, B19' monoclinic martensite variants in NiTi alloys are identified unambiguously, by using numerical comparison between the experimental and theoretical rotation components, without the reference of retained parent phase. (C) 2020 Elsevier B.V. All rights reserved. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000581134200033 |
Publication Date |
2020-09-07 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0167-577x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
; This work was supported by National Natural Science Foundation of China under Grant Nos. 51571092 and 51401081, and Guangdong Provincial Natural Science Foundation under Grant Nos. 2018B0303110012 and 2017A030313323. ; |
Approved |
Most recent IF: 3; 2020 IF: 2.572 |
|
| |
Call Number |
UA @ admin @ c:irua:173509 |
Serial |
6540 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Nicolas-Boluda, A.; Yang, Z.; Dobryden, I.; Carn, F.; Winckelmans, N.; Pechoux, C.; Bonville, P.; Bals, S.; Claesson, P.M.; Gazeau, F.; Pileni, M.P. |
|
| |
Title |
Intracellular fate of hydrophobic nanocrystal self-assemblies in tumor cells |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
|
| |
Volume |
30 |
Issue |
40 |
Pages |
2004274-15 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Control of interactions between nanomaterials and cells remains a biomedical challenge. A strategy is proposed to modulate the intralysosomal distribution of nanoparticles through the design of 3D suprastructures built by hydrophilic nanocrystals (NCs) coated with alkyl chains. The intracellular fate of two water-dispersible architectures of self-assembled hydrophobic magnetic NCs: hollow deformable shells (colloidosomes) or solid fcc particles (supraballs) is compared. These two self-assemblies display increased cellular uptake by tumor cells compared to dispersions of the water-soluble NC building blocks. Moreover, the self-assembly structures increase the NCs density in lysosomes and close to the lysosome membrane. Importantly, the structural organization of NCs in colloidosomes and supraballs are maintained in lysosomes up to 8 days after internalization, whereas initially dispersed hydrophilic NCs are randomly aggregated. Supraballs and colloidosomes are differently sensed by cells due to their different architectures and mechanical properties. Flexible and soft colloidosomes deform and spread along the biological membranes. In contrast, the more rigid supraballs remain spherical. By subjecting the internalized suprastructures to a magnetic field, they both align and form long chains. Overall, it is highlighted that the mechanical and topological properties of the self-assemblies direct their intracellular fate allowing the control intralysosomal density, ordering, and localization of NCs. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000559913300001 |
Publication Date |
2020-08-27 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
19 |
Times cited |
11 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; F.G. and M.P.P. contributed equally to this work. Dr. J. Teixeira from Laboratoire Leon Brillouin CEA Saclay is thanked for fruitful discussions on SAXS measurement. Dr. J.M. Guinier is thanked for cryoTEM experiments. A.N.-B. received a Ph.D. fellowship from the Institute thematique multi-organismes (ITMO) Cancer and the doctoral school Frontieres du Vivant (FdV)-Programme Bettencourt and the Fondation ARC pour la recherche sur le cancer. ; |
Approved |
Most recent IF: 19; 2020 IF: 12.124 |
|
| |
Call Number |
UA @ admin @ c:irua:171145 |
Serial |
6551 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Parsons, T.G.; Hadermann, J.; Halasyamani, P.S.; Hayward, M.A. |
|
| |
Title |
Preparation of the noncentrosymmetric ferrimagnetic phase La0.9Ba0.1Mn0.96O2.43 by topochemical reduction |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Solid State Chemistry |
Abbreviated Journal |
J Solid State Chem |
|
| |
Volume |
287 |
Issue |
|
Pages |
121356-121357 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Topochemical reduction of La0.9Ba0.1MnO3 with NaH at 225 degrees C yields the brownmillerite phase La0.9Ba0.1MnO2.5. However, reduction with CaH2 at 435 degrees C results in the formation of La0.9Ba0.1Mn0.96O2.43 via the deintercalation of both oxide anions and manganese cations from the parent perovskite phase. Electron and neutron diffraction data reveal La0.9Ba0.1Mn0.96O2.43 adopts a complex noncentrosymmetric structure, described in space group I23, confirmed by SHG measurements. Low-temperature neutron diffraction data reveal La0.9Ba0.1Mn0.96O2.43 adopts an ordered magnetic structure in which all the nearest neighbor interactions are antiferromagnetic. However, the presence of ordered manganese cation-vacancies results in a net ferrimagnetic structure with net saturated moment of 0.157(2) mu B per manganese center. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000533632700029 |
Publication Date |
2020-04-05 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0022-4596 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
3.3 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
; We thank the EPSRC for funding this work and E. Suard for assisting with the collection of the neutron powder diffraction data. PSH thanks the Welch Foundation (Grant E-1457) for support. ; |
Approved |
Most recent IF: 3.3; 2020 IF: 2.299 |
|
| |
Call Number |
UA @ admin @ c:irua:169450 |
Serial |
6583 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Lu, Y.; Liu, X.-L.; He, L.; Zhang, Y.-X.; Hu, Z.-Y.; Tian, G.; Cheng, X.; Wu, S.-M.; Li, Y.-Z.; Yang, X.-H.; Wang, L.-Y.; Liu, J.-W.; Janiak, C.; Chang, G.-G.; Li, W.-H.; Van Tendeloo, G.; Yang, X.-Y.; Su, B.-L. |
|
| |
Title |
Spatial heterojunction in nanostructured TiO₂ and its cascade effect for efficient photocatalysis |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
|
| |
Volume |
20 |
Issue |
5 |
Pages |
3122-3129 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
A highly efficient photoenergy conversion is strongly dependent on the cumulative cascade efficiency of the photogenerated carriers. Spatial heterojunctions are critical to directed charge transfer and, thus, attractive but still a challenge. Here, a spatially ternary titanium-defected TiO2@carbon quantum dots@reduced graphene oxide (denoted as V-Ti@CQDs@rGO) in one system is shown to demonstrate a cascade effect of charges and significant performances regarding the photocurrent, the apparent quantum yield, and photocatalysis such as H-2 production from water splitting and CO2 reduction. A key aspect in the construction is the technologically irrational junction of Ti-vacancies and nanocarbons for the spatially inside-out heterojunction. The new “spatial heterojunctions” concept, characteristics, mechanism, and extension are proposed at an atomic- nanoscale to clarify the generation of rational heterojunctions as well as the cascade electron transfer. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000535255300024 |
Publication Date |
2020-04-28 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
10.8 |
Times cited |
5 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; This work was supported by the joint National Natural Science Foundation of China-Deutsche Forschungsgemeinschaft (NSFC-DFG) project (NSFC grant 51861135313, DFG JA466/39-1), Fundamental Research Funds for the Central Universities (19lgpy113, 19lgzd16), Program for Changjiang Scholars and Innovative Research Team in University (IRT_15R52) and Jilin Province Science and Technology Development Plan (20180101208JC). ; |
Approved |
Most recent IF: 10.8; 2020 IF: 12.712 |
|
| |
Call Number |
UA @ admin @ c:irua:170263 |
Serial |
6608 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ding, L.; Raskin, J.-P.; Lumbeeck, G.; Schryvers, D.; Idrissi, H. |
|
| |
Title |
TEM investigation of the role of the polycrystalline-silicon film/substrate interface in high quality radio frequency silicon substrates |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Materials Characterization |
Abbreviated Journal |
Mater Charact |
|
| |
Volume |
161 |
Issue |
|
Pages |
110174-10 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The microstructural characteristics of two polycrystalline silicon (poly-Si) films with different electrical properties produced by low-pressure chemical vapour deposition on top of high resistivity silicon substrates were investigated by advanced transmission electron microscopy (TEM), including high resolution aberration corrected TEM and automated crystallographic orientation mapping in TEM. The results reveal that the nature of the poly-Si film/Si substrate interface is the main factor controlling the electrical resistivity of the poly-Si films. The high resistivity and high electrical linearity of poly-Si films are strongly promoted by the Sigma 3 twin type character of the poly-Si/Si substrate interface, leading to the generation of a huge amount of extended defects including stacking faults, Sigma 3 twin boundaries as well as Sigma 9 grain boundaries at this interface. Furthermore, a high density of interfacial dislocations has been observed at numerous common and more exotic grain boundaries deviating from their standard crystallographic planes. In contrast, poly-Si film/Si substrate interfaces with random character do not favour the formation of such complex patterns of defects, leading to poor electrical resistivity of the poly-Si film. This finding opens windows for the development of high resistivity silicon substrates for Radio Frequency (RF) integrated circuits (ICs) applications. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000521515800027 |
Publication Date |
2020-01-30 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1044-5803 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.7 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
; H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). ; |
Approved |
Most recent IF: 4.7; 2020 IF: 2.714 |
|
| |
Call Number |
UA @ admin @ c:irua:168664 |
Serial |
6621 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Cautaerts, N.; Delville, R.; Stergar, E.; Pakarinen, J.; Verwerft, M.; Yang, Y.; Hofer, C.; Schnitzer, R.; Lamm, S.; Felfer, P.; Schryvers, D. |
|
| |
Title |
The role of Ti and TiC nanoprecipitates in radiation resistant austenitic steel: A nanoscale study |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acta Materialia |
Abbreviated Journal |
Acta Mater |
|
| |
Volume |
197 |
Issue |
|
Pages |
184-197 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
This work encompasses an in-depth transmission electron microscopy and atom probe tomography study of Ti-stabilized austenitic steel irradiated with Fe-ions. The focus is on radiation induced segregation and precipitation, and in particular on how Ti and TiC affect these processes. A 15-15Ti steel (grade: DIN 1.4970) in two thermo-mechanical states (cold-worked and aged) was irradiated at different temperatures up to a dose of 40 dpa. At low irradiation temperatures, the cold-worked and aged materials evolved to a similar microstructure dominated by small Si and Ni clusters, corresponding to segregation to small point defect clusters. TiC precipitates, initially present in the aged material, were found to be unstable under these irradiation conditions. Elevated irradiation temperatures resulted in the nucleation of nanometer sized Cr enriched TiC precipitates surrounded by Si and Ni enriched shells. In addition, nanometer sized Ti- and Mn-enriched G-phase (M6Ni16Si7) precipitates formed, often attached to TiC precipitates. Post irradiation, larger number densities of TiC were observed in the cold-worked material compared to the aged material. This was correlated with a lower volume fraction of G-phase. The findings suggest that at elevated irradiation temperatures, the precipitate-matrix interface is an important point defect sink and contributes to the improved radiation resistance of this material. The study is a first of its kind on stabilized steel and demonstrates the significance of the small Ti addition to the evolution of the microstructure under irradiation. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000564767000001 |
Publication Date |
2020-07-10 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1359-6454 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
9.4 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
; This work was supported by ENGIE [contract number 2015-AC-007 e BSUEZ6900]; the U.S. Department of Energy, Office of Nuclear Energy under DOE Idaho Operations Office Contract DE-AC07051D14517 as part of a Nuclear Science User Facilities experiment; and by the MYRRHA program at SCK-CEN, Belgium. Funding of the Austrian BMK (846933) in the framework of the program “Production of the future” and the “BMK Professorship for Industry” is gratefully acknowledged. We want to thank the staffat MIBL for assisting with the ion irradiations as well as the staffat CAES for assisting with FIB work and conducting APT measurements. ; |
Approved |
Most recent IF: 9.4; 2020 IF: 5.301 |
|
| |
Call Number |
UA @ admin @ c:irua:171956 |
Serial |
6626 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Wang, H.S.; Chen, L.; Elibol, K.; He, L.; Wang, H.; Chen, C.; Jiang, C.; Li, C.; Wu, T.; Cong, C.X.; Pennycook, T.J.; Argentero, G.; Zhang, D.; Watanabe, K.; Taniguchi, T.; Wei, W.; Yuan, Q.; Meyer, J.C.; Xie, X. |
|
| |
Title |
Towards chirality control of graphene nanoribbons embedded in hexagonal boron nitride |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Nature Materials |
Abbreviated Journal |
Nat Mater |
|
| |
Volume |
|
Issue |
|
Pages |
1-10 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Oriented trenches are created in h-BN using different catalysts, and used as templates to grow seamlessly integrated armchair and zigzag graphene nanoribbons with chirality-dependent electrical and magnetic conductance properties. The integrated in-plane growth of graphene nanoribbons (GNRs) and hexagonal boron nitride (h-BN) could provide a promising route to achieve integrated circuitry of atomic thickness. However, fabrication of edge-specific GNRs in the lattice of h-BN still remains a significant challenge. Here we developed a two-step growth method and successfully achieved sub-5-nm-wide zigzag and armchair GNRs embedded in h-BN. Further transport measurements reveal that the sub-7-nm-wide zigzag GNRs exhibit openings of the bandgap inversely proportional to their width, while narrow armchair GNRs exhibit some fluctuation in the bandgap-width relationship. An obvious conductance peak is observed in the transfer curves of 8- to 10-nm-wide zigzag GNRs, while it is absent in most armchair GNRs. Zigzag GNRs exhibit a small magnetic conductance, while armchair GNRs have much higher magnetic conductance values. This integrated lateral growth of edge-specific GNRs in h-BN provides a promising route to achieve intricate nanoscale circuits. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000571692500001 |
Publication Date |
2020-09-21 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1476-1122; 1476-4660 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
41.2 |
Times cited |
3 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; H.W. and X.X. thank J.H. Edgar (Kansas State University, USA) for supplying the partial h-BN crystals. H. S. Wang, L. Chen and H. Wang thank M. Liu, X. Qiu and J. Pan from NCNT of China, F. Liou, H. Tsai, M. Crommie from UCB, USA, J. Xue and P. Yu from ShanghaiTech University and S. Wang from SJTU for nc-AFM measurement. H. S. Wang, L. Chen and H. Wang thank B. Sun and S. Li from Hunan University for the fusion of the STEM image and the electron energy loss spectroscopy mapping images. Funding: The work was partially supported by the National Key R&D program (Grant No. 2017YFF0206106), the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB30000000), the National Science Foundation of China (Grant No. 51772317, 51302096, 61774040, 91964102), the Science and Technology Commission of Shanghai Municipality (Grant No. 16ZR1442700, 16ZR1402500 18511110700), Shanghai Rising-Star Program (A type) (Grant No.18QA1404800), the Hubei Provincial Natural Science Foundation of China (Grant No. ZRMS2017000370), China Postdoctoral Science Foundation (Grant No. 2017M621563, 2018T110415), and the Fundamental Research Funds of Wuhan City (No. 2016060101010075). C.L. acknowledges support from the European Union's Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grants No. 656378 – Interfacial Reactions. T.J.P. acknowledges funding from European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie grant agreement no. 655760-DIGIPHASE. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan and the CREST (JPMJCR15F3), JST. C.X.C. acknowledges financial support from the National Young 1000 Talent Plan of China and the National Key R&D Program of China (No. 2018YFA0703700). L.H. acknowledges financial support from the programme of China Scholarships Council (No. 201706160037). ; |
Approved |
Most recent IF: 41.2; 2020 IF: 39.737 |
|
| |
Call Number |
UA @ admin @ c:irua:171944 |
Serial |
6633 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Chaves, A.; Moura, V.N.; Linard, F.J.A.; Covaci, L.; Milošević, M.V. |
|
| |
Title |
Tunable magnetic focusing using Andreev scattering in superconductor-graphene hybrid devices |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
|
| |
Volume |
128 |
Issue |
12 |
Pages |
124303 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
| |
Abstract |
We perform the wavepacket dynamics simulation of a graphene-based device where propagating electron trajectories are tamed by an applied magnetic field toward a normal/superconductor interface. The magnetic field controls the incidence angle of the incoming electronic wavepacket at the interface, which results in the tunable electron-hole ratio in the reflected wave function due to the angular dependence of the Andreev reflection. Here, mapped control of the quasiparticle trajectories by the external magnetic field not only defines an experimental probe for fundamental studies of the Andreev reflection in graphene but also lays the foundation for further development of magnetic focusing devices based on nanoengineered superconducting two-dimensional materials. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000576393200002 |
Publication Date |
2020-09-28 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.2 |
Times cited |
1 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; This work was supported by the Brazilian Council for Research (CNPq) through the PRONEX/FUNCAP and PQ programs and by the Research Foundation-Flanders (FWO). ; |
Approved |
Most recent IF: 3.2; 2020 IF: 2.068 |
|
| |
Call Number |
UA @ admin @ c:irua:172730 |
Serial |
6639 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Han, Y.; Zeng, Y.; Hendrickx, M.; Hadermann, J.; Stephens, P.W.; Zhu, C.; Grams, C.P.; Hemberger, J.; Frank, C.; Li, S.; Wu, M.X.; Retuerto, M.; Croft, M.; Walker, D.; Yao, D.-X.; Greenblatt, M.; Li, M.-R. |
|
| |
Title |
Universal a-cation splitting in LiNbO₃-type structure driven by intrapositional multivalent coupling |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of The American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
|
| |
Volume |
142 |
Issue |
15 |
Pages |
7168-7178 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Understanding the electric dipole switching in multiferroic materials requires deep insight of the atomic-scale local structure evolution to reveal the ferroelectric mechanism, which remains unclear and lacks a solid experimental indicator in high-pressure prepared LiNbO3-type polar magnets. Here, we report the discovery of Zn-ion splitting in LiNbO3-type Zn2FeNbO6 established by multiple diffraction techniques. The coexistence of a high-temperature paraelectric-like phase in the polar Zn2FeNbO6 lattice motivated us to revisit other high-pressure prepared LiNbO3-type A(2)BB'O-6 compounds. The A-site atomic splitting (similar to 1.0-1.2 angstrom between the split-atom pair) in B/B'-mixed Zn2FeTaO6 and O/N-mixed ZnTaO2N is verified by both powder X-ray diffraction structural refinements and high angle annular dark field scanning transmission electron microscopy images, but is absent in single-B-site ZnSnO3. Theoretical calculations are in good agreement with experimental results and suggest that this kind of A-site splitting also exists in the B-site mixed Mn-analogues, Mn2FeMO6 (M = Nb, Ta) and anion-mixed MnTaO2N, where the smaller A-site splitting (similar to 0.2 angstrom atomic displacement) is attributed to magnetic interactions and bonding between A and B cations. These findings reveal universal A-site splitting in LiNbO3-type structures with mixed multivalent B/B', or anionic sites, and the splitting-atomic displacement can be strongly suppressed by magnetic interactions and/or hybridization of valence bands between d electrons of the A- and B-site cations. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000526300600046 |
Publication Date |
2020-03-27 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
15 |
Times cited |
1 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; This work was supported by the National Science Foundation of China (NSFC-21875287), the Program for Guangdong Introducing Innovative and Entrepreneurial Teams (2017ZT07C069), and an NSF-DMR-1507252 grant (U.S.). Use of the NSLS, Brookhaven National Laboratory, was supported by the DOE BES (DE-AC02-98CH10886). M.R. is thankful for the Spanish Juan de la Cierva grant FPDI-2013-17582. Y.Z. and D.-X.Y. are supported by NKRDPC-2018YFA0306001, NKRDPC-2017YFA0206203, NSFC-11974432, NSFG-2019A1515011337, the National Supercomputer Center in Guangzhou, and the Leading Talent Program of Guangdong Special Projects. Work on IOP, CAS, was supported by NSFC and MOST grants. A portion of this research at ORNL's Spallation Neutron Source was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy. J.H. and M.H. thank the FWO for support for the electron microscopy studies through grant G035619N. We thank beamline BL14B1 (Shanghai Synchrotron Radiation Facility) for providing beam time and help during the experiments. ; |
Approved |
Most recent IF: 15; 2020 IF: 13.858 |
|
| |
Call Number |
UA @ admin @ c:irua:170294 |
Serial |
6646 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Volykhov, A.A.; Frolov, A.S.; Neudachina, V.S.; Vladimirova, N.V.; Gerber, E.; Callaert, C.; Hadermann, J.; Khmelevsky, N.O.; Knop-Gericke, A.; Sanchez-Barriga, J.; Yashina, L.V. |
|
| |
Title |
Impact of ordering on the reactivity of mixed crystals of topological insulators with anion substitution: Bi₂SeTe₂ and Sb₂SeTe₂ |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Applied Surface Science |
Abbreviated Journal |
Appl Surf Sci |
|
| |
Volume |
541 |
Issue |
|
Pages |
148490 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Three-dimensional topological insulators are exotic materials with unique properties. Tetradymite type binary chalcogenides of bismuth and antimony, as well as their mixed crystals, belong to prototypical TIs. Potential device applications of these materials require in-depth knowledge of their stability in the ambient atmosphere and other media maintained during their processing. Here we investigated the reactivity of mixed crystals with anion substitution, Bi-2(Se1-xTex)(3) and Sb2(Se1-xTex)(3), towards molecular oxygen using both in situ and ex situ X-ray photoelectron spectroscopy. The results indicate that, in contrast to cation substitution, partial substitution of tellurium by selenium atoms leads to anomalously high surface reactivity, which even exceeds that of the most reactive binary constituent. We attribute this effect to anion ordering that essentially modifies the bond geometry, especially the respective bond angles as modeled by DFT. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000608492900003 |
Publication Date |
2020-11-18 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0169-4332 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.387 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.387 |
|
| |
Call Number |
UA @ admin @ c:irua:176067 |
Serial |
6728 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Fatermans, J.; de Backer, A.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
Atom column detection |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
177-214 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
| |
Abstract |
By combining statistical parameter estimation and model-order selection using a Bayesian framework, the maximum a posteriori (MAP) probability rule is proposed in this chapter as an objective and quantitative method to detect atom columns from high-resolution scanning transmission electron microscopy (HRSTEM) images. The validity and usefulness of this approach is demonstrated to both simulated and experimental annular dark-field (ADF) STEM images, but also to simultaneously acquired annular bright-field (ABF) and ADF STEM image data. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177531 |
Serial |
6775 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
Atom counting |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
91-144 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
| |
Abstract |
In this chapter, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high-resolution annular dark-field (ADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. We show that this method can be applied to nanocrystals of arbitrary shape, size, and atom type. The validity of the atom-counting results is confirmed by means of detailed image simulations and it is shown that the high sensitivity of our method enables us to count atoms with single atom sensitivity. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177529 |
Serial |
6776 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
Efficient fitting algorithm |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
73-90 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic-resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighboring columns, enabling the analysis of a large field of view. To provide end-users with this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. In this chapter, this efficient algorithm is applied to three different nanostructures for which the analysis of a large field of view is required. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177528 |
Serial |
6778 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
General conclusions and future perspectives |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
243-253 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
| |
Abstract |
This chapter provides an overview of statistical and quantitative methodologies that have pushed (scanning) transmission electron microscopy ((S)TEM) toward accurate and precise measurements of unknown structure parameters for understanding the relation between the structure of a material and its properties. Hereby, statistical parameter estimation theory has extensively been used which enabled not only measuring atomic column positions, but also quantifying the number of atoms, and detecting atomic columns as accurately and precisely as possible from experimental images. As a general conclusion, it can be stated that advanced statistical techniques are ideal tools to perform quantitative electron microscopy at the atomic scale. In the future, statistical methods will continue to be developed and novel quantification procedures will open up new possibilities for studying material structures at the atomic scale. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177533 |
Serial |
6781 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Fatermans, J.; de Backer, A.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
Image-quality evaluation and model selection with maximum a posteriori probability |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
215-242 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
| |
Abstract |
The maximum a posteriori (MAP) probability rule for atom column detection can also be used as a tool to evaluate the relation between scanning transmission electron microscopy (STEM) image quality and atom detectability. In this chapter, a new image-quality measure is proposed that correlates well with atom detectability, namely the integrated contrast-to-noise ratio (ICNR). Furthermore, the working principle of the MAP probability rule is described in detail showing a close relation to the principles of model-selection methods. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177532 |
Serial |
6782 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
Introduction |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
1-28 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
|
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177525 |
Serial |
6784 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
Optimal experiment design for nanoparticle atom counting from ADF STEM images |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
145-175 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
| |
Abstract |
In this chapter, the principles of detection theory are used to quantify the probability of error for atom counting from high-resolution scanning transmission electron microscopy (HRSTEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom counting using the expression of the probability of error. We show that for very thin objects the low-angle annular dark-field (LAADF) regime is optimal and that for thicker objects the optimal inner detector angle increases. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177530 |
Serial |
6785 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
| |
Title |
Statistical parameter estimation theory : principles and simulation studies |
Type |
H2 Book chapter |
| |
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
29-72 |
|
| |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
| |
Abstract |
In this chapter, the principles of statistical parameter estimation theory for a quantitative analysis of atomic-resolution electron microscopy images are introduced. Within this framework, electron microscopy images are described by a parametric statistical model. Here, parametric models are introduced for different types of electron microscopy images: reconstructed exit waves, annular dark-field (ADF) scanning transmission electron microscopy (STEM) images, and simultaneously acquired ADF and annular bright-field (ABF) STEM images. Furthermore, the Cramér-Rao lower bound (CRLB) is introduced, i.e. a theoretical lower bound on the variance of any unbiased estimator. This CRLB is used to quantify the precision of the structure parameters of interest, such as the atomic column positions and the integrated atomic column intensities. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:177527 |
Serial |
6788 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Fu, Y.; Ding, L.; Singleton, M.L.; Idrissi, H.; Hermans, S. |
|
| |
Title |
Synergistic effects altering reaction pathways : the case of glucose hydrogenation over Fe-Ni catalysts |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Applied Catalysis B-Environmental |
Abbreviated Journal |
Appl Catal B-Environ |
|
| |
Volume |
288 |
Issue |
|
Pages |
119997 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Carbon black (CB) supported Ni, Fe, or Fe-Ni alloy catalysts were synthesized by sol-gel to elucidate the reaction pathways over each catalyst, as well as synergistic effects in glucose to sorbitol hydrogenation. The bimetallic materials presented small and alloyed nanoparticles that were richer in reduced metallic sites at the surface than their monometallic counterparts. Glucose isomerization to fructose was favoured over Fe/CB, while glucose hydrogenation to sorbitol is the dominating pathway over Ni/CB catalyst. By contrast, sorbitol production was promoted and undesired isomerization was suppressed when Fe and Ni formed a nanoalloy. In addition, the alloy catalyst presented better stability than the corresponding monometallic catalyst. A comparison with a mechanical mixture of Fe/CB and Ni/CB monometallic catalysts demonstrated the synergy at the nanoscale in the alloy. By comparing different Fe:Ni ratios, the 1:1 formulation was identified as the best compromise to achieve a high activity while maintaining high sorbitol selectivity. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000632996500002 |
Publication Date |
2021-02-17 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0926-3373 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
9.446 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: 9.446 |
|
| |
Call Number |
UA @ admin @ c:irua:177621 |
Serial |
6789 |
|
| Permanent link to this record |
| |
|
| |
|
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 |
|
| |
Title |
Topochemical deintercalation of Li from layered LiNiB : toward 2D MBene |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of The American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
|
| |
Volume |
143 |
Issue |
11 |
Pages |
4213-4223 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The pursuit of two-dimensional (2D) borides, MBenes, has proven to be challenging, not the least because of the lack of a suitable precursor prone to the deintercalation. Here, we studied room-temperature topochemical deintercalation of lithium from the layered polymorphs of the LiNiB compound with a considerable amount of Li stored in between [NiB] layers (33 at. % Li). Deintercalation of Li leads to novel metastable borides (Li similar to 0.5NiB) with unique crystal structures. Partial removal of Li is accomplished by exposing the parent phases to air, water, or dilute HCl under ambient conditions. Scanning transmission electron microscopy and solid-state Li-7 and B-1(1) NMR spectroscopy, combined with X-ray pair distribution function (PDF) analysis and DFT calculations, were utilized to elucidate the novel structures of (Li similar to 0.5NiB) and the mechanism of Li-deintercalation. We have shown that the deintercalation of Li proceeds via a “zip-lock” mechanism, leading to the condensation of single [NiB] layers into double or triple layers bound via covalent bonds, resulting in structural fragments with Li[NiB](2) and Li[NiB](3) compositions. The crystal structure of Li similar to 0.5NiB is best described as an intergrowth of the ordered single [NiB], double [NiB](2), or triple [NiB](3) layers alternating with single Li layers; this explains its structural complexity. The formation of double or triple [NiB] layers induces a change in the magnetic behavior from temperature-independent paramagnets in the parent LiNiB compounds to the spin-glassiness in the deintercalated Li similar to 0.5NiB counterparts. LiNiB compounds showcase the potential to access a plethora of unique materials, including 2D MBenes (NiB). |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000634761500021 |
Publication Date |
2021-03-15 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
13.858 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: 13.858 |
|
| |
Call Number |
UA @ admin @ c:irua:177697 |
Serial |
6790 |
|
| Permanent link to this record |
| |
|
| |
|
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. |
|
| |
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 |
| |
Year |
2021 |
Publication |
Journal Of Catalysis |
Abbreviated Journal |
J Catal |
|
| |
Volume |
393 |
Issue |
|
Pages |
313-323 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
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. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000640923500003 |
Publication Date |
2020-11-26 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0021-9517 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.844 |
Times cited |
40 |
Open Access |
Not_Open_Access |
|
| |
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 |
|
| |
Call Number |
UA @ admin @ c:irua:178321 |
Serial |
6796 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Skorikov, A.; Heyvaert, W.; Albrecht, W.; Pelt, D.M.; Bals, S. |
|
| |
Title |
EMAT Simulated 3D Nanoparticle Structures Dataset |
Type |
Dataset |
| |
Year |
2021 |
Publication |
|
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
Dataset; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
This dataset contains 1000 simulated nanoparticle-like 3D structures and noisy EDX-like elemental maps based on them. These data are intended to be used for quantitative analysis of data processing methods in (EDX) tomography of nanoparticles and training the data-driven approaches for these tasks. The dataset is structured as follows: voxel_data/clean 3D voxel grid representation of the simulated nanoparticles. Voxel intensities are adjusted so that the total intensity equals 103. All 3D structures have unique identifiers in 0..999 range. The data derived from a 3D structure preserves this unique identifier. sinograms/clean Tilt series of projection images obtained from the corresponding 3D structures over an angular range of -75..75 degrees with a tilt step of 10 degrees to simulate a typical tilt series used in EDX tomography. Total intensity in each projection image equals 103. sinograms/noisy Tilt series of projection images corrupted with Poisson noise and an additional spatially uniform background noise. projections/clean Projection images extracted from the clean tilt series at 0 degrees tilt angle. projections/noisy Projection images extracted from the noisy tilt series at 0 degrees tilt angle. images/clean Visualizations of the clean projections as PNG images with the intensity range adjusted to 0..255 images/noisy Visualizations of the noisy projections as PNG images with the intensity range adjusted to 0..255 |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:180615 |
Serial |
6838 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Abakumov, A.M.; Li, C.; Boev, A.; Aksyonov, D.A.; Savina, A.A.; Abakumova, T.A.; Van Tendeloo, G.; Bals, S. |
|
| |
Title |
Grain boundaries as a diffusion-limiting factor in lithium-rich NMC cathodes for high-energy lithium-ion batteries |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
|
|
| |
Volume |
4 |
Issue |
7 |
Pages |
6777-6786 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
High-energy lithium-rich layered transition metal oxides are capable of delivering record electrochemical capacity and energy density as positive electrodes for Li-ion batteries. Their electrochemical behavior is extremely complex due to sophisticated interplay between crystal structure, electronic structure, and defect structure. Here we unravel an extra level of this complexity by revealing that the most typical representative Li1.2Ni0.13Mn0.54Co0.13O2 material, prepared by a conventional coprecipitation technique with Na2CO3 as a precipitating agent, contains abundant coherent (001) grain boundaries with a Na-enriched P2-structured block due to segregation of the residual sodium traces. The trigonal prismatic oxygen coordination of Na triggers multiple nanoscale twinning, giving rise to incoherent (104) boundaries. The cationic layers at the (001) grain boundaries are filled with transition metal cations being Mn-depleted and Co-enriched; this makes them virtually not permeable for the Li+ cations, and therefore they negatively influence the Li diffusion in and out of the spherical agglomerates. These results demonstrate that besides the mechanisms intrinsic to the crystal and electronic structure of Li-rich cathodes, their rate capability might also be depreciated by peculiar microstructural aspects. Dedicated engineering of grain boundaries opens a way for improving inherently sluggish kinetics of these materials. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000678382900042 |
Publication Date |
2021-07-02 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2574-0962 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
4 |
Open Access |
Not_Open_Access |
|
| |
Notes |
We thank Dr. M. V. Berekchiian (MSU) for assisting in ICPMS measurements. We acknowledge Russian Science Foundation (Grant 20-43-01012) and Research Foundation Flanders (FWO Vlaanderen, Project No. G0F1320N) for financial support. |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:180556 |
Serial |
6841 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Shi, R.; Choudhuri, D.; Kashiwar, A.; Dasari, S.; Wang, Y.; Banerjee, R.; Banerjee, D. |
|
| |
Title |
α phase growth and branching in titanium alloys |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Philosophical magazine |
Abbreviated Journal |
Philos Mag |
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
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. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000722082700001 |
Publication Date |
2021-11-24 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1478-6435 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
1.505 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: 1.505 |
|
| |
Call Number |
UA @ admin @ c:irua:183616 |
Serial |
6849 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Peng, X.; Peng, H.; Zhao, K.; Zhang, Y.; Xia, F.; Lyu, J.; Van Tendeloo, G.; Sun, C.; Wu, J. |
|
| |
Title |
Direct visualization of atomic-scale heterogeneous structure dynamics in MnO₂ nanowires |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
|
| |
Volume |
13 |
Issue |
28 |
Pages |
33644-33651 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
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. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000677540900101 |
Publication Date |
2021-07-08 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
7.504 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: 7.504 |
|
| |
Call Number |
UA @ admin @ c:irua:180450 |
Serial |
6861 |
|
| Permanent link to this record |
