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| Author | van Thiel, T. c.; Brzezicki, W.; Autieri, C.; Hortensius, J. r.; Afanasiev, D.; Gauquelin, N.; Jannis, D.; Janssen, N.; Groenendijk, D. j.; Fatermans, J.; Van Aert, S.; Verbeeck, J.; Cuoco, M.; Caviglia, A. d. | ||||
| Title | Coupling Charge and Topological Reconstructions at Polar Oxide Interfaces | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 127 | Issue | 12 | Pages | 127202 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion symmetry across the heterointerfaces. A notable example is the interface between polar and nonpolar materials, where valence discontinuities lead to otherwise inaccessible charge and spin states. This approach paved the way for the discovery of numerous unconventional properties absent in the bulk constituents. However, control of the geometric structure of the electronic wave functions in correlated oxides remains an open challenge. Here, we create heterostructures consisting of ultrathin SrRuO3, an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and LaAlO3, a polar wide-band-gap insulator. Transmission electron microscopy reveals an atomically sharp LaO/RuO2/SrO interface configuration, leading to excess charge being pinned near the LaAlO3/SrRuO3 interface. We demonstrate through magneto-optical characterization, theoretical calculations and transport measurements that the real-space charge reconstruction drives a reorganization of the topological charges in the band structure, thereby modifying the momentum-space Berry curvature in SrRuO3. Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000704665000010 | Publication Date | 2021-09-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.462 | Times cited | 17 | Open Access | OpenAccess |
| Notes | The authors thank E. Lesne, M. Lee, H. Barakov, M. Matthiesen and U. Filippozzi for discussions. The authors are grateful to E.J.S. van Thiel for producing the illustration in Fig. 4a. This work was supported by the European Research Council under the European Unions Horizon 2020 programme/ERC Grant agreements No. [677458], [770887] and No. [731473] (Quantox of QuantERA ERA-NET Cofund in Quantum Technologies) and by the Netherlands Organisation for Scientific Research (NWO/OCW) as part of the Frontiers of Nanoscience (NanoFront) and VIDI program. The authors acknowledge funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. [823717] – ESTEEM3. N. G., J. V., and S. V. A. acknowledge funding from the University of Antwerp through the Concerted Research Actions (GOA) project Solarpaint and the TOP project. C. A. and W. B. are supported by the Foundation for Polish Science through the International Research Agendas program co-financed by the European Union within the Smart Growth Operational Programme. C. A. acknowledges access to the computing facilities of the Interdisciplinary Center of Modeling at the University of Warsaw, Grant No. G73-23 and G75-10. W.B. acknowledges support from the Narodowe Centrum Nauk (NCN, National Science Centre, Poland) Project No. 2019/34/E/ST3/00404'; esteem3TA; esteem3reported | Approved | Most recent IF: 8.462 | ||
| Call Number | EMAT @ emat @c:irua:182595 | Serial  |
6824 | ||
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| Author | Koo, J.; Dahl, A.B.; Bærentzen, J.A.; Chen, Q.; Bals, S.; Dahl, V.A. | ||||
| Title | Shape from projections via differentiable forward projector for computed tomography | Type | A1 Journal article | ||
| Year | 2021 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 224 | Issue | Pages | 113239 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In computed tomography, the reconstruction is typically obtained on a voxel grid. In this work, however, we propose a mesh-based reconstruction method. For tomographic problems, 3D meshes have mostly been studied to simulate data acquisition, but not for reconstruction, for which a 3D mesh means the inverse process of estimating shapes from projections. In this paper, we propose a differentiable forward model for 3D meshes that bridge the gap between the forward model for 3D surfaces and optimization. We view the forward projection as a rendering process, and make it differentiable by extending recent work in differentiable rendering. We use the proposed forward model to reconstruct 3D shapes directly from projections. Experimental results for single-object problems show that the proposed method outperforms traditional voxel-based methods on noisy simulated data. We also apply the proposed method on electron tomography images of nanoparticles to demonstrate the applicability of the method on real data. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000744576800008 | Publication Date | 2021-03-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 3 | Open Access | OpenAccess |
| Notes | EU Horizon 2020 MSCA Innovative Training Network MUMMERING Grant Number 765604. | Approved | Most recent IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:183267 | Serial |
6825 | ||
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| Author | Van Loenhout, J.; Freire Boullosa, L.; Quatannens, D.; De Waele, J.; Merlin, C.; Lambrechts, H.; Lau, H.W.; Hermans, C.; Lin, A.; Lardon, F.; Peeters, M.; Bogaerts, A.; Smits, E.; Deben, C. | ||||
| Title | Auranofin and Cold Atmospheric Plasma Synergize to Trigger Distinct Cell Death Mechanisms and Immunogenic Responses in Glioblastoma | Type | A1 Journal Article;oxidative stress | ||
| Year | 2021 | Publication | Cells | Abbreviated Journal | Cells |
| Volume | 10 | Issue | 11 | Pages | 2936 |
| Keywords | A1 Journal Article;oxidative stress; auranofin; cold atmospheric plasma; glioblastoma; cancer cell death; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | Targeting the redox balance of malignant cells via the delivery of high oxidative stress unlocks a potential therapeutic strategy against glioblastoma (GBM). We investigated a novel reactive oxygen species (ROS)-inducing combination treatment strategy, by increasing exogenous ROS via cold atmospheric plasma and inhibiting the endogenous protective antioxidant system via auranofin (AF), a thioredoxin reductase 1 (TrxR) inhibitor. The sequential combination treatment of AF and cold atmospheric plasma-treated PBS (pPBS), or AF and direct plasma application, resulted in a synergistic response in 2D and 3D GBM cell cultures, respectively. Differences in the baseline protein levels related to the antioxidant systems explained the cell-line-dependent sensitivity towards the combination treatment. The highest decrease of TrxR activity and GSH levels was observed after combination treatment of AF and pPBS when compared to AF and pPBS monotherapies. This combination also led to the highest accumulation of intracellular ROS. We confirmed a ROS-mediated response to the combination of AF and pPBS, which was able to induce distinct cell death mechanisms. On the one hand, an increase in caspase-3/7 activity, with an increase in the proportion of annexin V positive cells, indicates the induction of apoptosis in the GBM cells. On the other hand, lipid peroxidation and inhibition of cell death through an iron chelator suggest the involvement of ferroptosis in the GBM cell lines. Both cell death mechanisms induced by the combination of AF and pPBS resulted in a significant increase in danger signals (ecto-calreticulin, ATP and HMGB1) and dendritic cell maturation, indicating a potential increase in immunogenicity, although the phagocytotic capacity of dendritic cells was inhibited by AF. In vivo, sequential combination treatment of AF and cold atmospheric plasma both reduced tumor growth kinetics and prolonged survival in GBM-bearing mice. Thus, our study provides a novel therapeutic strategy for GBM to enhance the efficacy of oxidative stress-inducing therapy through a combination of AF and cold atmospheric plasma. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000807134000001 | Publication Date | 2021-10-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2073-4409 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | OpenAccess | ||
| Notes | Olivia Hendrickx Research Fund, 21OCL06 ; University of Antwerp, FFB160231 ; The authors would express their gratitude to Hans de Reu for technical assistance with flow cytometry. | Approved | Most recent IF: NA | ||
| Call Number | PLASMANT @ plasmant @c:irua:182915 | Serial |
6826 | ||
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| Author | Van Alphen, S.; Slaets, J.; Ceulemans, S.; Aghaei, M.; Snyders, R.; Bogaerts, A. | ||||
| Title | Effect of N2 on CO2-CH4 conversion in a gliding arc plasmatron: Can this major component in industrial emissions improve the energy efficiency? | Type | A1 Journal Article;Plasma-based CO2-CH4 conversion | ||
| Year | 2021 | Publication | Journal Of Co2 Utilization | Abbreviated Journal | J Co2 Util |
| Volume | 54 | Issue | Pages | 101767 | |
| Keywords | A1 Journal Article;Plasma-based CO2-CH4 conversion; Effect of N2; Plasma chemistry; Computational modelling; Gliding arc plasmatron; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | Plasma-based CO2 and CH4 conversion is gaining increasing interest, and a great portion of research is dedicated to adapting the process to actual industrial conditions. In an industrial context, the process needs to be able to process N2 admixtures, since most industrial gas emissions contain significant amounts of N2, and gas separations are financially costly. In this paper we therefore investigate the effect of N2 on the CO2 and CH4 conversion in a gliding arc plasmatron reactor. The addition of 20 % N2 reduces the energy cost of the conversion process by 21 % compared to a pure CO2/CH4 mixture, from 2.9 down to 2.2 eV/molec (or from 11.5 to 8.7 kJ/L), yielding a CO2 and CH4 (absolute) conversion of 28.6 and 35.9 % and an energy efficiency of 58 %. These results are among the best reported in literature for plasma-based DRM, demonstrating the benefits of N2 present in the mix. Compared to DRM results in different plasma reactor types, a low energy cost was achieved. To understand the underlying mechanisms of N2 addition, we developed a combination of four different computational models, which reveal that the beneficial effect of N2 addition is attributed to (i) a rise in the electron density (increasing the plasma conductivity, and therefore reducing the plasma power needed to sustain the plasma, which reduces the energy cost), as well as (ii) a rise in the gas temperature, which accelerates the CO2 and CH4 conversion reactions. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000715057300005 | Publication Date | 2021-10-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2212-9820 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.292 | Times cited | Open Access | OpenAccess | |
| Notes | This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innova tion programme (grant agreement No 810182 – SCOPE ERC Synergy project), the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023), and through long-term structural funding (Methusalem). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. | Approved | Most recent IF: 4.292 | ||
| Call Number | PLASMANT @ plasmant @c:irua:184044 | Serial |
6827 | ||
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| Author | Jannis, D.; Hofer, C.; Gao, C.; Xie, X.; Béché, A.; Pennycook, Tj.; Verbeeck, J. | ||||
| Title | Event driven 4D STEM acquisition with a Timepix3 detector: Microsecond dwell time and faster scans for high precision and low dose applications | Type | A1 Journal article | ||
| Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 233 | Issue | Pages | 113423 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Four dimensional scanning transmission electron microscopy (4D STEM) records the scattering of electrons in a material in great detail. The benefits offered by 4D STEM are substantial, with the wealth of data it provides facilitating for instance high precision, high electron dose efficiency phase imaging via centre of mass or ptychography based analysis. However the requirement for a 2D image of the scattering to be recorded at each probe position has long placed a severe bottleneck on the speed at which 4D STEM can be performed. Recent advances in camera technology have greatly reduced this bottleneck, with the detection efficiency of direct electron detectors being especially well suited to the technique. However even the fastest frame driven pixelated detectors still significantly limit the scan speed which can be used in 4D STEM, making the resulting data susceptible to drift and hampering its use for low dose beam sensitive applications. Here we report the development of the use of an event driven Timepix3 direct electron camera that allows us to overcome this bottleneck and achieve 4D STEM dwell times down to 100 ns; orders of magnitude faster than what has been possible with frame based readout. We characterize the detector for different acceleration voltages and show that the method is especially well suited for low dose imaging and promises rich datasets without compromising dwell time when compared to conventional STEM imaging. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000734396800003 | Publication Date | 2021-11-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.2 | Times cited | 31 | Open Access | OpenAccess |
| Notes | This project has received funding from the Euro- pean Union’s Horizon 2020 Research Infrastructure – Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3. J.V. and A.B. acknowledge funding from FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’). J.V. and D.J. ac- knowledge funding from FWO project G042920N ‘Co- incident event detection for advanced spectroscopy in transmission electron microscopy’. We acknowledge funding under the European Union’s Horizon 2020 re- search and innovation programme (J.V. and D.J un- der grant agreement No 101017720, FET-Proactive EBEAM, and C.H., C.G., X.X. and T.J.P. from the Eu- ropean Research Council (ERC) Grant agreement No. 802123-HDEM).; esteem3JRA; esteem3reported | Approved | Most recent IF: 2.2 | ||
| Call Number | EMAT @ emat @c:irua:183948 | Serial |
6828 | ||
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| Author | Walters, A.A.; Santacana-Font, G.; Li, J.; Routabi, N.; Qin, Y.; Claes, N.; Bals, S.; Tzu-Wen Wang, J.; Al-Jamal, K.T. | ||||
| Title | Nanoparticle-MediatedIn SituMolecular Reprogramming of Immune Checkpoint Interactions for Cancer Immunotherapy | Type | A1 Journal article | ||
| Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
| Volume | 15 | Issue | 11 | Pages | 17549-17564 |
| Keywords | A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Immune checkpoint blockade involves targeting immune regulatory molecules with antibodies. Preclinically, complex multiantibody regimes of both inhibitory and stimulatory targets are a promising candidate for the next generation of immunotherapy. However, in this setting, the antibody platform may be limited due to excessive toxicity caused by off target effects as a result of systemic administration. RNA can be used as an alternate to antibodies as it can both downregulate immunosuppressive checkpoints (siRNA) or induce expression of immunostimulatory checkpoints (mRNA). In this study, we demonstrate that the combination of both siRNA and mRNA in a single formulation can simultaneously knockdown and induce expression of immune checkpoint targets, thereby reprogramming the tumor microenvironment from immunosuppressive to immunostimulatory phenotype. To achieve this, RNA constructs were synthesized and formulated into stable nucleic acid lipid nanoparticles (SNALPs); the SNALPs produced were 140−150 nm in size with >80% loading efficiency. SNALPs could transfect macrophages and B16F10 cells in vitro resulting in 75% knockdown of inhibitory checkpoint (PDL1) expression and simultaneously express high levels of stimulatory checkpoint (OX40L) with minimal toxicity. Intratumoral treatment with the proposed formulation resulted in statistically reduced tumor growth, a greater density of CD4+ and CD8+ infiltrates in the tumor, and immune activation within tumor-draining lymph nodes. These data suggest that a single RNA-based formulation can successfully reprogram multiple immune checkpoint interactions on a cellular level. Such a candidate may be able to replace future immune checkpoint therapeutic regimes composed of both stimulatory- and inhibitory-receptor-targeting antibodies. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000747115200039 | Publication Date | 2021-11-23 | |
| 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 | 13.942 | Times cited | 11 | Open Access | OpenAccess |
| Notes | A.A.W. is the grateful recipient of a Maplethorpe Fellowship. K.A.J. acknowledges funding from the British Council (Newton Fund, 337313), Wellcome Trust (WT103913), and the Cancer Research UK King’s Health Partners Centre at King’s College London. Financial support is acknowledged from the European Commission under the Horizon 2020 Programme, by means of Grant Agreement No. 731019 (EUSMI). Images were drawn on BioRender.com. | Approved | Most recent IF: 13.942 | ||
| Call Number | EMAT @ emat @c:irua:183950 | Serial |
6829 | ||
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| Author | Bruggeman, P.J.; Bogaerts, A.; Pouvesle, J.M.; Robert, E.; Szili, E.J. | ||||
| Title | Plasma–liquid interactions | Type | A1 Journal Article | ||
| Year | 2021 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
| Volume | 130 | Issue | 20 | Pages | 200401 |
| Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | |||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | Publication Date | 2021-11-28 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979 | ISBN | Additional Links | UA library record | |
| Impact Factor | 2.068 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 2.068 | |||
| Call Number | PLASMANT @ plasmant @c:irua:184245 | Serial |
6830 | ||
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| Author | Renero-Lecuna, C.; Herrero, A.; Jimenez de Aberasturi, D.; Martínez-Flórez, M.; Valiente, R.; Mychinko, M.; Bals, S.; Liz-Marzán, L.M. | ||||
| Title | Nd3+-Doped Lanthanum Oxychloride Nanocrystals as Nanothermometers | Type | A1 Journal article | ||
| Year | 2021 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 125 | Issue | 36 | Pages | 19887-19896 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The development of optical nanothermometers operating in the near-infrared (NIR) is of high relevance toward temperature measurements in biological systems. We propose herein the use of Nd3+-doped lanthanum oxychloride nanocrystals as an efficient system with intense photoluminescence under NIR irradiation in the first biological transparency window and emission in the second biological window with excellent emission stability over time under 808 nm excitation, regardless of Nd3+ concentration, which can be considered as a particular strength of our system. Additionally, surface passivation through overgrowth of an inert LaOCl shell around optically active LaOCl/Nd3+ cores was found to further enhance the photoluminescence intensity and also the lifetime of the 1066 nm, 4F3/2 to 4I11/2 transition, without affecting its (ratiometric) sensitivity toward temperature changes. As required for biological applications, we show that the obtained (initially hydrophobic) nanocrystals can be readily transferred into aqueous solvents with high, long-term stability, through either ligand exchange or encapsulation with an amphiphilic polymer. | ||||
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| Language | Wos | 000697335100031 | Publication Date | 2021-09-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 9 | Open Access | OpenAccess |
| Notes | The authors thank the financial support of the European Research Council (ERC-AdG-2017 787510, ERC-CoG-2019 815128) and of the European Commission (EUSMI, Grant 731019). This work was performed under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency−Grant MDM-2017−0720. Realnano; sygmaSB | Approved | Most recent IF: 4.536 | ||
| Call Number | EMAT @ emat @c:irua:181671 | Serial |
6831 | ||
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| Author | Mushtaq, A.; Pradhan, B.; Kushavah, D.; Zhang, Y.; Wolf, M.; Schrenker, N.; Fron, E.; Bals, S.; Hofkens, J.; Debroye, E.; Pal, S.K. | ||||
| Title | Third-Order Nonlinear Optical Properties and Saturation of Two-Photon Absorption in Lead-Free Double Perovskite Nanocrystals under Femtosecond Excitation | Type | A1 Journal article | ||
| Year | 2021 | Publication | Acs Photonics | Abbreviated Journal | Acs Photonics |
| Volume | 8 | Issue | 11 | Pages | 3365-3374 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Lead halide perovskites have been widely explored in the field of photovoltaics, light-emitting diodes, and lasers due to their outstanding linear and nonlinear optical (NLO) properties. But, the presence of lead toxicity and low chemical stability remain serious concerns. Lead-free double perovskite with excellent optical properties and chemical stability could be an alternative. However, proper examination of the NLO properties of such a material is crucial to identify their utility for future nonlinear device applications. Herein, we have made use of femtosecond (fs) Z-scan technique to explore the NLO properties of Cs2AgIn0.9Bi0.1Cl6 nanocrystals (NCs). Our measurements suggest that under nonresonant fs excitation, perovskite NCs exhibit strong twophoton absorption (TPA). The observed saturation of TPA at high light intensities has been explained by a customized model. Furthermore, we have demonstrated a change in the nonlinear refractive index of the NCs under varying input intensities. The strong TPA absorption of lead-free double perovskite NCs could be used for Kerr nonlinearity-based nonlinear applications such as optical shutters for picosecond lasers. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000757024100028 | Publication Date | 2021-11-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2330-4022 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.756 | Times cited | 25 | Open Access | OpenAccess |
| Notes | A.M. is thankful to IIT Mandi for his fellowship and Advanced Materials Research Centre for the experimental facilities. A.M. is also thankful to Torbjörn Pascher (Pascher Instrument) for writing the Z-scan data acquisition program. J.H. acknowledges financial support from the Research Foundation-Flanders (FWO, Grant No. G983.19N, G0A5817N, and G0H6316N) and the Flemish government through long-term structural funding Methusalem (CASAS2, Meth/15/04). B.P. acknowledges postdoctoral fellowship from the Research Foundation- Flanders (FWO Grant No. 1275521N). D.K. acknowledges the financial support from Science and Engineering Research Board (Grant No. PDF/2018/003146), India. N.J.S. acknowledges financial support from the Research Foundation- Flanders via a postdoctoral fellowship (FWO Grant No. 1238622N). | Approved | Most recent IF: 6.756 | ||
| Call Number | EMAT @ emat @c:irua:184249 | Serial |
6832 | ||
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| Author | Feng, X.; Jena, H.S.; Krishnaraj, C.; Arenas-Esteban, D.; Leus, K.; Wang, G.; Sun, J.; Rüscher, M.; Timoshenko, J.; Roldan Cuenya, B.; Bals, S.; Voort, P.V.D. | ||||
| Title | Creation of Exclusive Artificial Cluster Defects by Selective Metal Removal in the (Zn, Zr) Mixed-Metal UiO-66 | Type | A1 Journal article | ||
| Year | 2021 | Publication | Journal Of The American Chemical Society | Abbreviated Journal | J Am Chem Soc |
| Volume | Issue | Pages | jacs.1c05357 | ||
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The differentiation between missing linker defects and missing cluster defects in MOFs is difficult, thereby limiting the ability to correlate materials properties to a specific type of defects. Herein, we present a novel and easy synthesis strategy for the creation of solely “missing cluster defects” by preparing mixed-metal (Zn, Zr)-UiO-66 followed by a gentle acid wash to remove the Zn nodes. The resulting material has the reo UiO-66 structure, typical for well-defined missing cluster defects. The missing clusters are thoroughly characterized, including low-pressure Ar-sorption, iDPCSTEM at a low dose (1.5 pA), and XANES/EXAFS analysis. We show that the missing cluster UiO-66 has a negligible number of missing linkers. We show the performance of the missing cluster UiO-66 in CO2 sorption and heterogeneous catalysis. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000730569500001 | Publication Date | 2021-12-07 | |
| 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 | 29 | Open Access | OpenAccess |
| Notes | Agentschap Innoveren en Ondernemen, HBC.2019.0110 HBC.2021.0254 ; Universiteit Gent; Fonds Wetenschappelijk Onderzoek, 665501 ; Dalian University of Technology; China Scholarship Council, 201507565009 ; National Natural Science Foundation of China, 22101039 ; H2020 European Research Council, 815128 REALNANO ; sygmaSB | Approved | Most recent IF: 13.858 | ||
| Call Number | EMAT @ emat @c:irua:183951 | Serial |
6833 | ||
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| Author | Mustonen, K.; Hofer, C.; Kotrusz, P.; Markevich, A.; Hulman, M.; Mangler, C.; Susi, T.; Pennycook, T.J.; Hricovini, K.; Richter, C.M.; Meyer, J.C.; Kotakoski, J.; Skákalová, V. | ||||
| Title | Towards Exotic Layered Materials: 2D Cuprous Iodide | Type | A1 Journal article | ||
| Year | 2021 | Publication | Advanced materials | Abbreviated Journal | Adv Mater |
| Volume | Issue | Pages | 2106922 | ||
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Heterostructures composed of two-dimensional (2D) materials are already opening many new possibilities in such fields of technology as electronics and magnonics, but far more could be achieved if the number and diversity of 2D materials is increased. So far, only a few dozen 2D crystals have been extracted from materials that exhibit a layered phase in ambient conditions, omitting entirely the large number of layered materials that may exist in other temperatures and pressures. Here, we demonstrate how these structures can be stabilized in 2D van der Waals stacks under room temperature via growing them directly in graphene encapsulation by using graphene oxide as the template material. Specifically, we produce an ambient stable 2D structure of copper and iodine, a material that normally only occurs in layered form at elevated temperatures between 645 and 675 K. Our results establish a simple route to the production of more exotic phases of materials that would otherwise be difficult or impossible to stabilize for experiments in ambient. | ||||
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| Language | Wos | 000744012500001 | Publication Date | 2021-12-07 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0935-9648 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 19.791 | Times cited | Open Access | OpenAccess | |
| Notes | We acknowledge funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme Grant agreements No.~756277-ATMEN (A.M. and T.S.) and No.802123-HDEM (C.H. and T.J.P.). Computational resources from the Vienna Scientific Cluster (VSC) are gratefully acknowledged. V.S. was supported by the Austrian Science Fund (FWF) (project no. I2344-N36), the Slovak Research and Development Agency (APVV-16-0319), the project CEMEA of the Slovak Academy of Sciences, ITMS project code 313021T081 of the Research & Innovation Operational Programme and from the V4-Japan Joint Research Program (BGapEng). J.K. acknowledges the FWF funding within project P31605-N36 and M.H. the funding from Slovak Research and Development Agency via the APVV-15-0693 and APVV-19-0365 project grants. Danubia NanoTech s.r.o. has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101008099 (CompSafeNano project) and also thanks Mr. Kamil Bernath for his support. | Approved | Most recent IF: 19.791 | ||
| Call Number | EMAT @ emat @c:irua:183956 | Serial |
6834 | ||
| Permanent link to this record | |||||
| Author | Kelly, S.; Bogaerts, A. | ||||
| Title | Nitrogen fixation in an electrode-free microwave plasma | Type | A1 Journal Article | ||
| Year | 2021 | Publication | Joule | Abbreviated Journal | Joule |
| Volume | 5 | Issue | 11 | Pages | 3006-3030 |
| Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | Plasma-based gas conversion has great potential for enabling carbon-free fertilizer production powered by renewable electricity. Sustaining an energy-efficient plasma process without eroding the containment vessel is currently a significant challenge, limiting scaling to higher powers and throughputs. Isolation of the plasma from contact with any solid surfaces is an advantage, which both limits energy loss to the walls and prevents material erosion that could lead to disastrous soil contamination. This paper presents highly energy-efficient nitrogen fixation from air into NOx by microwave plasma, with the plasma filament isolated at the center of a quartz tube using a vortex gas flow. NOx production is found to scale very efficiently when increasing both gas flow rate and absorbed power. The lowest energy cost recorded of ~2 MJ/mol, for a total NOx production of ~3.8%, is the lowest reported up to now for atmospheric pressure plasmas. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000723010700018 | Publication Date | 2021-10-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2542-4351 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | OpenAccess | ||
| Notes | We acknowledge financial support by the European Marie Skłodowska-Curie Individual Fellowship ‘‘PENFIX’’ within Horizon 2020 (grant no. 838181), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no 810182 – SCOPE ERC Synergy project), and the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Centre VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. We thank Dr. Waldo Bongers and Dr. Floran Peeters of the DIFFER institute for their help and advice in the initial phase of the project, as well as Mr. Luc van‘t Dack, Dr. Karen Leyssens and Ing. Karel Venken for their technical assistance. We thank Dr. Klaus Werner, executive director of the RF Energy Alliance, for his extensive expertise and helpful discourse regarding solid-state MW technology. | Approved | Most recent IF: NA | ||
| Call Number | PLASMANT @ plasmant @c:irua:184250 | Serial |
6835 | ||
| Permanent link to this record | |||||
| Author | Pedrazo Tardajos, A. | ||||
| Title | Advanced graphene supports for 3D in situ transmission electron microscopy | Type | Doctoral thesis | ||
| Year | 2021 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 247 p. | ||
| Keywords | Doctoral thesis; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Transmission electron microscopy (TEM) is an ideal tool to investigate nanomaterials. The information from TEM experiments allows us to link the structure and composition of nanomaterials to their intrinsic physical properties. However, despite the significant evolution of the TEM field during the last two decades, major progress is still possible through the development of optimal TEM techniques and supports. The results presented in this thesis focus on the optimization of sample supports and their application. Among the different options, graphene has previously been reported as useful sample support for electron microscopy due to its unparalleled properties, for example, it is the thinnest known support and provides a protective effect to the sample under investigation. Unfortunately, commercial graphene grids show poor quality, in terms of intactness and cleanness, inhibiting their wide application within the field. Therefore, this thesis focuses on the application of optimized graphene TEM grids, obtained by transferring high quality graphene using an advanced procedure. This improvement on the transfer has enabled the visualization of materials with low contrast and high sensitivity towards the electron beam, such as surface ligands capping gold nanoparticles or metal halide perovskites. Furthermore, the implemented protocol is not only of interest for conventional TEM grids but also a major benefit for in situ TEM studies, where the sample is investigated in real time under certain stimuli. Hence, the same graphene transfer technology can be also applied to advanced in situ MEMS holders dedicated for both heating and gas experiments, where the thickness and insulating nature of the silicon nitride (Si3N4) support may hamper some applications. By engineering periodic arrays of holes in their Si3N4 membrane by focused ion beam, onto which the graphene is transferred, it has been possible to get proof-of-concept 3D in situ investigations of heat-induced morphological and compositional transformations of complex nanosystems. As an example, it has enabled the investigation of the possible phase-transition of metal halide perovskites upon heating using 2D and 3D structural characterization. Moreover, it has allowed the study of in situ three-dimensional nanoparticle dynamics during gas phase catalysis as well as the first steps that would lead towards the design and creation of the first Graphene Gas Cell. Consequently, implementation of the advanced graphene transfer technology described in this thesis is envisaged to impact a broad range of future experiments. | ||||
| 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 | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:181143 | Serial |
6836 | ||
| Permanent link to this record | |||||
| Author | Chee, S.-S.; Greboval, C.; Vale Magalhaes, D.; Ramade, J.; Chu, A.; Qu, J.; Rastogi, P.; Khalili, A.; Dang, T.H.; Dabard, C.; Prado, Y.; Patriarche, G.; Chaste, J.; Rosticher, M.; Bals, S.; Delerue, C.; Lhuillier, E. | ||||
| Title | Correlating structure and detection properties in HgTe nanocrystal films | Type | A1 Journal article | ||
| Year | 2021 | Publication | Nano Letters | Abbreviated Journal | Nano Lett |
| Volume | 21 | Issue | 10 | Pages | 4145-4151 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | HgTe nanocrystals (NCs) enable broadly tunable infrared absorption, now commonly used to design light sensors. This material tends to grow under multipodic shapes and does not present well-defined size distributions. Such point generates traps and reduces the particle packing, leading to a reduced mobility. It is thus highly desirable to comprehensively explore the effect of the shape on their performance. Here, we show, using a combination of electron tomography and tight binding simulations, that the charge dissociation is strong within HgTe NCs, but poorly shape dependent. Then, we design a dual-gate field-effect-transistor made of tripod HgTe NCs and use it to generate a planar p-n junction, offering more tunability than its vertical geometry counterpart. Interestingly, the performance of the tripods is higher than sphere ones, and this can be correlated with a stronger Te excess in the case of sphere shapes which is responsible for a higher hole trap density. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000657242300002 | Publication Date | 2021-05-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1530-6984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.712 | Times cited | 20 | Open Access | OpenAccess |
| Notes | The project is supported by ERC starting grant blackQD (Grant No. 756225) and consolidator grant Realnano (815128). This project has received funding from the European Commission (Grant 731019, EUSMI). We acknowledge the use of cleanroom facilities from the “Centrale de Proximité Paris-Centre”. This work has been supported by the Region Ile-de-France in the framework of DIM Nano-K (Grant dopQD). This work was supported by French state funds managed by the ANR within the Investissements d’Avenir programme under reference ANR11-IDEX-0004-02, and more specifically within the framework of the Cluster of Excellence MATISSE and also by grants IPERNano2 (ANR-18CE30-0023-01), Copin (ANR-19-CE24- 0022), Frontal (ANR-19-CE09-0017), Graskop (ANR-19- CE09-0026), and NITQuantum (ANR-20-ASTR-0008-01). A.C. thanks Agence innovation defense for Ph.D. funding; sygmaSB | Approved | Most recent IF: 12.712 | ||
| Call Number | UA @ admin @ c:irua:179127 | Serial |
6837 | ||
| 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 | Salzmann, B.B.V.; Vliem, J.F.; Maaskant, D.N.; Post, L.C.; Li, C.; Bals, S.; Vanmaekelbergh, D. | ||||
| Title | From CdSe nanoplatelets to quantum rings by thermochemical edge reconfiguration | Type | A1 Journal article | ||
| Year | 2021 | Publication | Chemistry Of Materials | Abbreviated Journal | Chem Mater |
| Volume | 33 | Issue | 17 | Pages | 6853-6859 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The variation in the shape of colloidal semiconductor nanocrystals (NCs) remains intriguing. This interest goes beyond crystallography as the shape of the NC determines its energy levels and optoelectronic properties. While thermodynamic arguments point to a few or just a single shape(s), terminated by the most stable crystal facets, a remarkable variation in NC shape has been reported for many different compounds. For instance, for the well-studied case of CdSe, close-to-spherical quantum dots, rods, two-dimensional nanoplatelets, and quantum rings have been reported. Here, we report how two-dimensional CdSe nanoplatelets reshape into quantum rings. We monitor the reshaping in real time by combining atomically resolved structural characterization with optical absorption and photoluminescence spectroscopy. We observe that CdSe units leave the vertical sides of the edges and recrystallize on the top and bottom edges of the nanoplatelets, resulting in a thickening of the rims. The formation of a central hole, rendering the shape into a ring, only occurs at a more elevated temperature. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000696553600024 | Publication Date | 2021-08-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0897-4756; 1520-5002 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 7 | Open Access | OpenAccess |
| Notes | Hans Meeldijk is kindly acknowledged for helping with electron microscopy at Utrecht University. B.B.V.S. and D.V. acknowledge the Dutch NWO for financial support via the TOP-ECHO grant no. 715.016.002. D.V. acknowledges financial support from the European ERC Council, ERC Advanced grant 692691 “First Step”. D.V. and L.C.P. acknowledge the Dutch NWO for financial support via the TOP-ECHO grant nr. 718.015.002. S.B acknowledges financial support from the European ERC Council, ERC Consolidator grant 815128. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 731019 (EUSMI). Realnano; sygmaSB | Approved | Most recent IF: 9.466 | ||
| Call Number | UA @ admin @ c:irua:181550 | Serial |
6839 | ||
| Permanent link to this record | |||||
| Author | Coeck, R.; Meeprasert, J.; Li, G.; Altantzis, T.; Bals, S.; Pidko, E.A.; De Vos, D.E. | ||||
| Title | Gold and silver-catalyzed reductive amination of aromatic carboxylic acids to benzylic amines | Type | A1 Journal article | ||
| Year | 2021 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
| Volume | 11 | Issue | 13 | Pages | 7672-7684 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
| Abstract | The reductive amination of benzoic acid and its derivatives would be an effective addition to current synthesis methods for benzylamine. However, with current technology it is very difficult to keep the aromaticity intact when starting from benzoic acid, and salt wastes are often generated in the process. Here, we report a heterogeneous catalytic system for such a reductive amination, requiring solely H-2 and NH3 as the reactants. The Ag/TiO2 or Au/TiO2 catalysts can be used multiple times, and very little noble metal is required, only 0.025 mol % Au. The catalysts are bifunctional: the support catalyzes the dehydration of both the ammonium carboxylate to the amide and of the amide to the nitrile, while the sites at the metal-support interface promote the hydrogenation of the in situ generated nitrile. Yields of up to 92% benzylamine were obtained. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000670659900005 | Publication Date | 2021-06-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 10.614 | Times cited | 16 | Open Access | OpenAccess |
| Notes | R.C. thanks the FWO for his SB PhD fellowship. D.E.D.V. acknowledges FWO for research project funding, as well as KU Leuven for funding in the Metusalem program Casas. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO). T.A. acknowledges funding from the University of Antwerp Research fund (BOF). E.A.P. acknowledges the support from the European Research Council (ERC Consolidator grant #725686 DeliCAT). J.M. acknowledges financial support through the Royal Thai Government Scholarship. DFT calculations on SURFsara supercomputer facilities were performed with support from the Netherlands Organization for Scientific Research (NWO).; sygmaSB | Approved | Most recent IF: 10.614 | ||
| Call Number | UA @ admin @ c:irua:179851 | Serial |
6840 | ||
| 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 | OpenAccess | |
| 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 | Du, K. | ||||
| Title | In situ TEM study on the manipulation of ferroelectrics | Type | Doctoral thesis | ||
| Year | 2021 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 91 p. | ||
| Keywords | Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The strong correlated oxide systems attract a lot of attentions of scientists recently, the coexistence and interplay between various degrees of freedom, such as charge, spin and orbital, has been demonstrated to induce some fancy physical properties and phenomenon, including metal-insulator transition, high temperature superconductivity, colossal magnetoresistance. As a part of the strong correlated oxide systems, the ferroelectrics is abundant in both physical properties and application. First, if the electric dipole continuously rotating around a stable core then a topological structure is produced. If people could manipulate the topological structure and simultaneously observe the structure evolution, with external field applied on the topological structure, then it is very likely for such kind of ferroelectrics to be the next generation of storage, for it is reported to need low power input and produce high density of storage. In the other hand, in solids, charge polarity can one-to-one correspond to spin polarity phenomenologically, such as ferroelectricity and ferromagnetism, antiferroelectricity and antiferromagnetism, but ferrielectricity and ferrimagnetism kept telling a disparate story in microscopic level. The claimed “ferrielectrics” in existing research is equivalent to ferroelectric ones, thus the findings of such a real irreducible solids would complete the last piece of the ferroelectrics family. While solving the above two questions remain challengeable: the size of topological structure is small (typically below 10 nm), general characterization methods are insufficient for such high demand on space resolution, not to mention manipulating and observing its dynamic behavior at an atomic level. Here, employing the spherical aberration corrected electron microscope, we applied external field (heating and bias) on ferroelectrics. Combined with high-end characterization methods including the high-angle annular dark field (HAADF-STEM) image, Electron Energy Loss Spectroscopy (EELS) and integrated differential phase contrast (iDPC), the dynamic evolution of ferroelectrics are observed and analyzed. The main findings of this paper could be concluded as listed here: (1) PbTiO3(001)// SrTiO3(001) is grown on DyScO3 and SrRuO3 by pusled laser deposition, the atomical EDS mapping results reveal that the interface between PTO and STO is atomically sharp. Increasing the thickness of PTO from 1 uc to 21 uc, the topological structure wihtin PTO layer would transform from a/c domain to wave, vortex and finally flux closure domain. The geometric phase analysis results (GPA) reveal that above topological structures are corresponding to various strain. (2) Combined with in-situ biasing holder, the electric bias was applied on polar vortex, and it evolved from vortex (0 V) to polar wave (2 V) and finally polar down (5 V). EELS analysis was performed and we find that negative charge is gathered at vortex core, which turns the Ti4+ to Ti3+ there. The oxygen vacancy at negative polarization surface and the negative charge at the positive polarization surface realized the polarization screening of polar down domain. (3) Through the atomic inspection and analysis on lattice structure of BaFe2Se3, the near ladders within single unit are found to be different in degree of tetramerization, thus leading to a residual polarization along the a-axis. The further in-situ heating and biasing experiment was conducted on BaFe2Se3, and the strong and weak ladders are proved to be independent for their behavior under external field. This findings distinguishes ferrielectrics from ferroelectrics in solids. | ||||
| 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 | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:179310 | Serial |
6842 | ||
| Permanent link to this record | |||||
| Author | Pramanik, G.; Kvakova, K.; Thottappali, M.A.; Rais, D.; Pfleger, J.; Greben, M.; El-Zoka, A.; Bals, S.; Dracinsky, M.; Valenta, J.; Cigler, P. | ||||
| Title | Inverse heavy-atom effect in near infrared photoluminescent gold nanoclusters | Type | A1 Journal article | ||
| Year | 2021 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
| Volume | 12 | Issue | 23 | Pages | 10462-10467 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Fluorophores functionalized with heavy elements show enhanced intersystem crossing due to increased spin-orbit coupling, which in turn shortens the fluorescence decay lifetime (tau(PL)). This phenomenon is known as the heavy-atom effect (HAE). Here, we report the observation of increased tau(PL) upon functionalisation of near-infrared photoluminescent gold nanoclusters with iodine. The heavy atom-mediated increase in tau(PL) is in striking contrast with the HAE and referred to as inverse HAE. Femtosecond and nanosecond transient absorption spectroscopy revealed overcompensation of a slight decrease in lifetime of the transition associated with the Au core (ps) by a large increase in the long-lived triplet state lifetime associated with the Au shell, which contributed to the observed inverse HAE. This unique observation of inverse HAE in gold nanoclusters provides the means to enhance the triplet excited state lifetime. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000657052500001 | Publication Date | 2021-06-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.367 | Times cited | 1 | Open Access | OpenAccess |
| Notes | The authors acknowledge support from GACR project no. 18-12533S. G. P. acknowledges support from EUSMI project no. E180200060; J. P. from the Ministry of Education, Youth and Sports of the Czech Republic – Program INTER-EXCELLENCE (LTAUSA19066). | Approved | Most recent IF: 7.367 | ||
| Call Number | UA @ admin @ c:irua:179052 | Serial |
6843 | ||
| Permanent link to this record | |||||
| Author | Choukroun, D.; Pacquets, L.; Li, C.; Hoekx, S.; Arnouts, S.; Baert, K.; Hauffman, T.; Bals, S.; Breugelmans, T. | ||||
| Title | Mapping composition–selectivity relationships of supported sub-10 nm Cu–Ag nanocrystals for high-rate CO₂ electroreduction | Type | A1 Journal article | ||
| Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
| Volume | 15 | Issue | 9 | Pages | 14858-14872 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
| Abstract | Colloidal Cu–Ag nanocrystals measuring less than 10 nm across are promising candidates for integration in hybrid CO2 reduction reaction (CO2RR) interfaces, especially in the context of tandem catalysis and selective multicarbon (C2–C3) product formation. In this work, we vary the synthetic-ligand/copper molar ratio from 0.1 to 1.0 and the silver/copper atomic ratio from 0 to 0.7 and study the variations in the nanocrystals’ size distribution, morphology and reactivity at rates of ≥100 mA cm–2 in a gas-fed recycle electrolyzer operating under neutral to mildly basic conditions (0.1–1.0 M KHCO3). High-resolution electron microscopy and spectroscopy are used in order to characterize the morphology of sub-10 nm Cu–Ag nanodimers and core–shells and to elucidate trends in Ag coverage and surface composition. It is shown that Cu–Ag nanocrystals can be densely dispersed onto a carbon black support without the need for immediate ligand removal or binder addition, which considerably facilitates their application. Although CO2RR product distribution remains an intricate function of time, (kinetic) overpotential and processing conditions, we nevertheless conclude that the ratio of oxygenates to hydrocarbons (which depends primarily on the initial dispersion of the nanocrystals and their composition) rises 3-fold at moderate Ag atom % relative to Cu NCs-based electrodes. Finally, the merits of this particular Cu–Ag/C system and the recycling reactor employed are utilized to obtain maximum C2–C3 partial current densities of 92–140 mA cm–2 at −1.15 VRHE and liquid product concentrations in excess of 0.05 wt % in 1 M KHCO3 after short electrolysis periods. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000703553600082 | Publication Date | 2021-08-24 | |
| 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 | 13.942 | Times cited | 25 | Open Access | OpenAccess |
| Notes | D.C. acknowledges Thomas Kenis for configuring the analytical instrumentation (HPLC/GC-FID/ICP-MS), Hannelore Andries for assistance with ICP-MS measurements, and Dr. Saeid Pourbabak and Dr. Tine Derez for assistance with Cu sputtering. L.P. was supported by Research Foundation of Flanders (FWO 1S56920N). S.B. acknowledges financial support from ERC Consolidator grant number 815128 REALNANO. S.B. and T.B. acknowledge financial support from the university research fund (BOF-GOA-PS ID no. 33928).; sygmaSB | Approved | Most recent IF: 13.942 | ||
| Call Number | UA @ admin @ c:irua:180305 | Serial |
6844 | ||
| Permanent link to this record | |||||
| Author | Wang, D.; van der Wee, E.B.; Zanaga, D.; Altantzis, T.; Wu, Y.; Dasgupta, T.; Dijkstra, M.; Murray, C.B.; Bals, S.; van Blaaderen, A. | ||||
| Title | Quantitative 3D real-space analysis of Laves phase supraparticles | Type | A1 Journal article | ||
| Year | 2021 | Publication | Nature Communications | Abbreviated Journal | Nat Commun |
| Volume | 12 | Issue | 1 | Pages | 3980 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
| Abstract | 3D real-space analysis of thick nanoparticle crystals is non-trivial. Here, the authors demonstrate the structural analysis of a bulk-like Laves phase by imaging an off-stoichiometric binary mixture of hard-sphere-like nanoparticles in spherical confinement by electron tomography, enabling defect analysis on the single-particle level. Assembling binary mixtures of nanoparticles into crystals, gives rise to collective properties depending on the crystal structure and the individual properties of both species. However, quantitative 3D real-space analysis of binary colloidal crystals with a thickness of more than 10 layers of particles has rarely been performed. Here we demonstrate that an excess of one species in the binary nanoparticle mixture suppresses the formation of icosahedral order in the self-assembly in droplets, allowing the study of bulk-like binary crystal structures with a spherical morphology also called supraparticles. As example of the approach, we show single-particle level analysis of over 50 layers of Laves phase binary crystals of hard-sphere-like nanoparticles using electron tomography. We observe a crystalline lattice composed of a random mixture of the Laves phases. The number ratio of the binary species in the crystal lattice matches that of a perfect Laves crystal. Our methodology can be applied to study the structure of a broad range of binary crystals, giving insights into the structure formation mechanisms and structure-property relations of nanomaterials. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000687320200032 | Publication Date | 2021-06-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 10 | Open Access | OpenAccess |
| Notes | M. Hermes is sincerely thanked for providing interactive views of the structures in this work. The authors thank I. Lobato, S. Dussi, L. Filion, E. Boattini, S. Paliwal, B. van der Meer and X. Xie for fruitful discussions. D.W., E.B.v.d.W. and A.v.B. acknowledge partial financial support from the European Research Council under the European Union’s Seventh Framework Program (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. T.D. and M.D. acknowledge financial support from the Industrial Partnership Program, “Computational Sciences for Energy Research” (Grant no. 13CSER025), of the Netherlands Organization for Scientific Research (NWO), which was co-financed by Shell Global Solutions International B.V. S.B. acknowledges financial support from ERC Consolidator Grant No. 815128 REALNANO. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). C.B.M and Y.W. acknowledge support for materials synthesis from the Office of Naval Research Multidisciplinary University Research Initiative Award ONR N00014-18-1-2497. The authors acknowledge EM Square center at Utrecht University for the access to the microscopes.; sygmaSB | Approved | Most recent IF: 12.124 | ||
| Call Number | UA @ admin @ c:irua:181662 | Serial |
6845 | ||
| Permanent link to this record | |||||
| Author | Dey, A.; Ye, J.; De, A.; Debroye, E.; Ha, S.K.; Bladt, E.; Kshirsagar, A.S.; Wang, Z.; Yin, J.; Wang, Y.; Quan, L.N.; Yan, F.; Gao, M.; Li, X.; Shamsi, J.; Debnath, T.; Cao, M.; Scheel, M.A.; Kumar, S.; Steele, J.A.; Gerhard, M.; Chouhan, L.; Xu, K.; Wu, X.-gang; Li, Y.; Zhang, Y.; Dutta, A.; Han, C.; Vincon, I.; Rogach, A.L.; Nag, A.; Samanta, A.; Korgel, B.A.; Shih, C.-J.; Gamelin, D.R.; Son, D.H.; Zeng, H.; Zhong, H.; Sun, H.; Demir, H.V.; Scheblykin, I.G.; Mora-Sero, I.; Stolarczyk, J.K.; Zhang, J.Z.; Feldmann, J.; Hofkens, J.; Luther, J.M.; Perez-Prieto, J.; Li, L.; Manna, L.; Bodnarchuk, M., I; Kovalenko, M., V; Roeffaers, M.B.J.; Pradhan, N.; Mohammed, O.F.; Bakr, O.M.; Yang, P.; Muller-Buschbaum, P.; Kamat, P., V; Bao, Q.; Zhang, Q.; Krahne, R.; Galian, R.E.; Stranks, S.D.; Bals, S.; Biju, V.; Tisdale, W.A.; Yan, Y.; Hoye, R.L.Z.; Polavarapu, L. | ||||
| Title | State of the art and prospects for Halide Perovskite Nanocrystals | Type | A1 Journal article | ||
| Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
| Volume | 15 | Issue | 7 | Pages | 10775-10981 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Metal-halide perovskites have rapidly emerged as one of the most promising materials of the 21st century, with many exciting properties and great potential for a broad range of applications, from photovoltaics to optoelectronics and photocatalysis. The ease with which metal-halide perovskites can be synthesized in the form of brightly luminescent colloidal nanocrystals, as well as their tunable and intriguing optical and electronic properties, has attracted researchers from different disciplines of science and technology. In the last few years, there has been a significant progress in the shape-controlled synthesis of perovskite nanocrystals and understanding of their properties and applications. In this comprehensive review, researchers having expertise in different fields (chemistry, physics, and device engineering) of metal-halide perovskite nanocrystals have joined together to provide a state of the art overview and future prospects of metal-halide perovskite nanocrystal research. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000679406500006 | Publication Date | 2021-06-17 | |
| 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 | 13.942 | Times cited | 538 | Open Access | OpenAccess |
| Notes | E.D. and J.H. acknowledge financial support from the Research FoundationFlanders (FWO Grant Nos. S002019N, G.0B39.15, G.0B49.15, G.0962.13, G098319N, and ZW15_09-GOH6316), the Research Foundation Flanders postdoctoral fellowships to J.A.S. and E.D. (FWO Grant Nos. 12Y7218N and 12O3719N, respectively), | Approved | Most recent IF: 13.942 | ||
| Call Number | UA @ admin @ c:irua:180553 | Serial |
6846 | ||
| Permanent link to this record | |||||
| Author | Prabhakara, V. | ||||
| Title | Strain measurement for semiconductor applications with Raman spectroscopy and Transmission electron microscopy | Type | Doctoral thesis | ||
| Year | 2021 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 149 p. | ||
| Keywords | Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Scaling down the size of transistors has been a trend for several decades which has led to improved transistor performance, increased transistor density and hence the overall computation power of IC chips. The trend slowed in recent years due to reliability and power consumption issues at the nanoscale. Hence strain is introduced into transistor channels that has beneficial effects on improving the mobility of charge carriers, providing an alternative pathway for enhancing transistor performance. Therefore, monitoring strain is vital for the semiconductor industry. With the recent trend of decreasing device dimensions (FinFETS ~ 10-20nm) and strain modulation being used throughout, industry needs a reliable and fast method as quality control or defect characterisation. Such a universal strain measurement method does not exist, and one relies on a combination of quantitative in-line methods and complex off-line approaches. In this thesis, I investigated TEM and Raman spectroscopy-based methodologies for strain measurement. In terms of TEM methodologies, advancements are made for the STEM moiré imaging, targeting strain spatial resolution enhancement. I introduce advanced quadrature demodulation and phase stepping interferometry applied to STEM moiré that greatly enhances the spatial resolution while providing enhanced field of view and sensitivity for strain measurement. We introduce ways to reduce scan distortions in strain maps using an alternative scan strategy called “Block scanning” and the non-linear regression applied for strain extraction. Prospects for 3D strain analysis using high-resolution tomography is also investigated which gives direct access for the full second order strain tensors calculation. Finally, we compare strain measurements from TEM techniques with inline techniques like Raman spectroscopy. Raman stress measurement involves sensitive identification of the TO and LO phonon peaks. Raman spectrum of strained Ge transistor channel consists of strongly overlapping peaks within the spectral resolution of the spectrometer. Hence, the process of deconvolution of the two peaks is rather challenging. Hence, we explore new polarisation geometries like radially polarised incoming light which was shown to ease the deconvolution problem resulting in improved precision for Raman stress–strain measurements. | ||||
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| 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 | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:182261 | Serial |
6847 | ||
| Permanent link to this record | |||||
| Author | Ma, R.; He, Y.; Feng, J.; Hu, Z.-Y.; Van Tendeloo, G.; Li, D. | ||||
| Title | A facile synthesis of Ag@PdAg core-shell architecture for efficient purification of ethene feedstock | Type | A1 Journal article | ||
| Year | 2019 | Publication | Journal of catalysis | Abbreviated Journal | |
| Volume | 369 | Issue | Pages | 440-449 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Precise control of elemental configurations within multimetallic nanoparticles could enable access to functional nanomaterials with significant performance benefits. Here, we present a one-pot synthesis of supported Ag@PdAg core-shell catalyst with an ordered PdAg alloy shell and an Ag core. Both the relative reduction potential and ratio of metal precursors are essential for this synthesis strategy. The distinguished properties of Ag@PdAg, particularly the electronic structure, indicates the existence of electron modification not only between Pd and Ag on PdAg shell, but between Ag core and alloy shell. The Ag@PdAg catalyst displays 97% ethene yield in the partial hydrogenation of acetylene, which is 2.0 and 8.1 times that of over PdAg alloy and pure Pd catalysts, and this is the most selective catalyst reported to data under industrial evaluation conditions. Moreover, this core-shell structure exhibits preferable stability with comparison to PdAg alloy catalyst. The facile synthesis of core-shell architecture with alloy shell structure provides a new platform for efficient catalytic transfer of chemical resource. (C) 2018 Elsevier Inc. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000460711700045 | Publication Date | 2018-12-11 | |
| 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 | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:181261 | Serial |
6848 | ||
| 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. | ||||
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| 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 | Madsen, J.; Pennycook, T.J.; Susi, T. | ||||
| Title | ab initio description of bonding for transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2021 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 231 | Issue | Pages | ||
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The simulation of transmission electron microscopy (TEM) images or diffraction patterns is often required to interpret their contrast and extract specimen features. This is especially true for high-resolution phase-contrast imaging of materials, but electron scattering simulations based on atomistic models are widely used in materials science and structural biology. Since electron scattering is dominated by the nuclear cores, the scattering potential is typically described by the widely applied independent atom model. This approximation is fast and fairly accurate, especially for scanning TEM (STEM) annular dark-field contrast, but it completely neglects valence bonding and its effect on the transmitting electrons. However, an emerging trend in electron microscopy is to use new instrumentation and methods to extract the maximum amount of information from each electron. This is evident in the increasing popularity of techniques such as 4D-STEM combined with ptychography in materials science, and cryogenic microcrystal electron diffraction in structural biology, where subtle differences in the scattering potential may be both measurable and contain additional insights. Thus, there is increasing interest in electron scattering simulations based on electrostatic potentials obtained from first principles, mainly via density functional theory, which was previously mainly required for holography. In this Review, we discuss the motivation and basis for these developments, survey the pioneering work that has been published thus far, and give our outlook for the future. We argue that a physically better justified ab initio description of the scattering potential is both useful and viable for an increasing number of systems, and we expect such simulations to steadily gain in popularity and importance. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000744190300006 | Publication Date | 2021-03-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 2.843 | |||
| Call Number | UA @ admin @ c:irua:183955 | Serial |
6850 | ||
| Permanent link to this record | |||||
| Author | Zhang, Z.; Bourgeois, L.; Zhang, Y.; Rosalie, J.M.; Medhekar, N. | ||||
| Title | Advanced imaging and simulations of precipitate interfaces in aluminium alloys and their role in phase transformations | Type | P1 Proceeding | ||
| Year | 2020 | Publication | MATEC web of conferences T2 – 17th International Conference on Aluminium Alloys (ICAA), October 26-29, 2020 | Abbreviated Journal | |
| Volume | Issue | Pages | 09003 | ||
| Keywords | P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Precipitation is accompanied by the formation and migration of heterophase interfaces. Using the combined approach of advanced imaging and atomistic simulations, we studied the precipitate-matrix interfaces in various aluminium alloy systems, aiming to resolve their detailed atomic structures and illuminate their role in phase transformations. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000652552200053 | Publication Date | 2020-11-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | 326 | Series Issue | Edition | ||
| ISSN | 2261-236x; 2274-7214 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:179147 | Serial |
6851 | ||
| Permanent link to this record | |||||
| Author | Velazco Torrejón, A. | ||||
| Title | Alternative scan strategies for high resolution STEM imaging | Type | Doctoral thesis | ||
| Year | 2021 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 131 p. | ||
| Keywords | Doctoral thesis; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Currently, a large variety of materials are studied by transmission electron microscopy (TEM) as it offers the possibility to perform structural and elemental analysis at a local scale. Relatively recent advances in aberration correctors and electron sources allow the instrument to achieve atomic resolution. Along with these advances, a state-of-the-art technology has been reached in TEM. However, the instrument is far from being perfect and imperfections or external sources can make the interpretation of information troublesome. Environmental factors such as acoustic and mechanical vibrations, temperature fluctuations, etc., can induce sample drift and create image distortions. These distortions are enhanced in scanning operation because of the serial acquisition of the information, which are more apparent at atomic resolution as small field of views are imaged. In addition, scanning distortions are induced due to the finite time response of the scan coils. These types of distortions would reduce precision in atomic-scale strain analysis, for instance, in semiconductors. Most of the efforts to correct these distortions are focused on data processing techniques post-acquisition. Another limitation in TEM is beam damage effects. Beam damage arises because of the energy transferred to the sample in electron-sample interactions. In scanning TEM, at atomic resolution, the increased electron charge density (electron dose) carried on a sub-Å size electron probe may aggravate beam damage effects. Soft materials such as zeolites, organic, biological materials, etc., can be destroyed under irradiation limiting the amount of information that can be acquired. Current efforts to circumvent beam damage are mostly based on low electron dose acquisitions and data processing methods to maximize the signal at low dose conditions. In this thesis, a different approach is given to address drift and scanning distortions, as well as beam damage effects. Novel scan strategies are proposed for that purpose, which are shown to substantially overcome these issues compared to the standard scan method in TEM. | ||||
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| 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 | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:180973 | Serial |
6852 | ||
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| Author | Wang, X.; Yao, X.; Schryvers, D.; Verlinden, B.; Wang, G.; Zhao, G.; Van Humbeeck, J.; Kustov, S. | ||||
| Title | Anomalous stress-strain behavior of NiTi shape memory alloy close to the border of superelastic window | Type | A1 Journal article | ||
| Year | 2021 | Publication | Scripta Materialia | Abbreviated Journal | Scripta Mater |
| Volume | 204 | Issue | Pages | 114135 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In this work, we report an anomalous phenomenon on superelastic cycling of NiTi shape memory alloys when deforming at the temperature close to the border of superelastic window. New unexpected effects are found-(i) critical stress for inducing martensite transformation during the second loading cycle is higher than that of the first cycle; ( ii ) the plateau stress of the second cycle decreases to the original level when the strain overcomes the limit of the first cycle; ( iii ) transition from good superelasticity in the first cycle to fully irreversible strain in the second. We propose that defects generated during the first superelastic cycle close to the border of superelastic window impede following stress-induced martensitic transformations, leading to the increase of critical stress beyond yield stress of the B2 matrix, and thus functional fatigue of NiTi alloys. (c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000690441400007 | Publication Date | 2021-07-14 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6462 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.747 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 3.747 | |||
| Call Number | UA @ admin @ c:irua:181658 | Serial |
6853 | ||
| Permanent link to this record | |||||