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Author | Arenas-Vivo, A.; Rojas, S.; Ocaña, I.; Torres, A.; Liras, M.; Salles, F.; Arenas-Esteban, D.; Bals, S.; Ávila, D.; Horcajada, P. | ||||
Title | Ultrafast reproducible synthesis of a Ag-nanocluster@MOF composite and its superior visible-photocatalytic activity in batch and in continuous flow | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Materials Chemistry A | Abbreviated Journal | J Mater Chem A |
Volume | 9 | Issue | 28 | Pages | 15704-15713 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The (photo)catalytic properties of metal–organic frameworks (MOFs) can be enhanced by post-synthetic inclusion of metallic species in their porosity. Due to their extraordinarily high surface area and well defined porous structure, MOFs can be used for the stabilization of metal nanoparticles with adjustable size within their porosity. Originally, we present here an optimized ultrafast photoreduction protocol for the<italic>in situ</italic>synthesis of tiny and monodisperse silver nanoclusters (AgNCs) homogeneously supported on a photoactive porous titanium carboxylate MIL-125-NH<sub>2</sub>MOF. The strong metal–framework interaction between –NH<sub>2</sub>and Ag atoms influences the AgNC growth, leading to the surfactant-free efficient catalyst AgNC@MIL-125-NH<sub>2</sub>with improved visible light absorption. The potential use of AgNC@MIL-125-NH<sub>2</sub>was further tested in challenging applications: (i) the photodegradation of the emerging organic contaminants (EOCs) methylene blue (MB-dye) and sulfamethazine (SMT-antibiotic) in water treatment, and (ii) the catalytic hydrogenation of<italic>p</italic>-nitroaniline (4-NA) to<italic>p</italic>-phenylenediamine (PPD) with industrial interest. It is noteworthy that compared with the pristine MIL-125-NH<sub>2</sub>, the composite presents an improved catalytic activity and stability, being able to photodegrade 92% of MB in 60 min and 96% of SMT in 30 min, and transform 100% of 4-NA to PPD in 30 min. Aside from these very good results, this study describes for the first time the use of a MOF in a visible light continuous flow reactor for wastewater treatment. With only 10 mg of AgNC@MIL-125-NH<sub>2</sub>, high SMT removal efficiency over 70% is maintained after >2 h under water flow conditions found in real wastewater treatment plants, signaling a future real application of MOFs in water remediation. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000671839200001 | Publication Date | 2021-06-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2050-7488 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.867 | Times cited | 18 | Open Access | OpenAccess |
Notes | Comunidad de Madrid, CAM PEJD-2016/IND-2828 Talento Modality 2, 2017-T2/IND-5149 ; Secretaría de Estado de Investigación, Desarrollo e Innovación, Raphuel project (ENE2016-79608-C2-1-R) Retos Project MAT2017-84385-R ; Ministerio de Ciencia e Innovación, Juan de la Cierva Incorporación Fellowship (grant agreement no. IJC2019-038894-I) MOFSEIDON project (PID2019-104228RB-I00) Ramón y Cajal, Grant Agreements 2014-15039 and 2015-18677 ; Fundación BBVA, IN[17]CBBQUI_0197 ; H2020 European Research Council, ERC Consolidator Grant REALNANO 815128 Grant Agreement no. 731019 (EUSMI) ; sygmaSB; | Approved | Most recent IF: 8.867 | ||
Call Number | EMAT @ emat @c:irua:179791 | Serial | 6802 | ||
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Author | Boschker, H.T.S.; Cook, P.L.M.; Polerecky, L.; Eachambadi, R.T.; Lozano, H.; Hidalgo-Martinez, S.; Khalenkow, D.; Spampinato, V.; Claes, N.; Kundu, P.; Wang, D.; Bals, S.; Sand, K.K.; Cavezza, F.; Hauffman, T.; Bjerg, J.T.; Skirtach, A.G.; Kochan, K.; McKee, M.; Wood, B.; Bedolla, D.; Gianoncelli, A.; Geerlings, N.M.J.; Van Gerven, N.; Remaut, H.; Geelhoed, J.S.; Millan-Solsona, R.; Fumagalli, L.; Nielsen, L.P.; Franquet, A.; Manca, J.V.; Gomila, G.; Meysman, F.J.R. | ||||
Title | Efficient long-range conduction in cable bacteria through nickel protein wires | Type | A1 Journal article | ||
Year | 2021 | Publication | Nature Communications | Abbreviated Journal | Nat Commun |
Volume | 12 | Issue | 1 | Pages | 3996 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Filamentous cable bacteria display long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on individual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating protein shell layer. The core proteins contain a sulfur-ligated nickel cofactor, and conductivity decreases when nickel is oxidized or selectively removed. The involvement of nickel as the active metal in biological conduction is remarkable, and suggests a hitherto unknown form of electron transport that enables efficient conduction in centimeter-long protein structures. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000669944900006 | Publication Date | 2021-06-28 | |
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 | 23 | Open Access | OpenAccess |
Notes | The authors thank Marlies Neiemeisland for assistance with Raman microscopy, Michiel Kienhuis for assistance with NanoSIMS analysis, Peter Hildebrandt and Diego Millo for helping with the interpretation of the Raman spectra, IONTOF for the Orbitrap Hybrid- SIMS analysis, and Rene Fabregas for helping with finite-element numerical modeling for SDM. H.T.S.B. and F.J.R.M. were financially supported by the Netherlands Organization for Scientific Research (VICI grant 016.VICI.170.072). Research Foundation Flanders supported F.J.R.M., J.V.M., and R.T.E. through FWO grant G031416N, and F.J.R.M. and J.S.G. through FWO grant G038819N. N.M.J.G. is the recipient of a Ph.D. scholarship for teachers from NWO in the Netherlands (grant 023.005.049). The NanoSIMS facility at Utrecht University was financed through a large infrastructure grant by the Netherlands Organization for Scientific Research (NWO, grant no. 175.010.2009.011) and through a Research Infrastructure Fund by the Utrecht University Board. A.G.S. is supported by the Special Research Fund (BOF) of Ghent University (BOF14/IOP/003, BAS094-18, 01IO3618) and FWO (G043219). The ToF-SIMS was funded by FWO Hercules grant (ZW/13/07) to J.V.M. and A.F. H.L., R.M.S., and G.G. were funded by the European Union H2020 Framework Programme (MSCA-ITN-2016) under grant agreement n 721874.EU, the Spanish Agencia Estatal de Investigación and EU FEDER under grant agreements TEC2016-79156-P and TEC2015-72751-EXP, the Generalitat de Catalunya through 2017-SGR1079 grant and CERCA Program. G.G. was recipient of an ICREA Academia Award, and H.L. of a FPI fellowship (BES-2015-074799) from the Agencia Estatal de Investigación/Fondo Social Europeo. L.F. received funding from the European Research Council (grant agreement No. 819417) under the European Union’s Horizon 2020 research and innovation programme. | Approved | Most recent IF: 12.124 | ||
Call Number | EMAT @ emat @c:irua:179813 | Serial | 6803 | ||
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Author | Mychinko, M.; Skorikov, A.; Albrecht, W.; Sánchez‐Iglesias, A.; Zhuo, X.; Kumar, V.; Liz‐Marzán, L.M.; Bals, S. | ||||
Title | The Influence of Size, Shape, and Twin Boundaries on Heat‐Induced Alloying in Individual Au@Ag Core–Shell Nanoparticles | Type | A1 Journal article | ||
Year | 2021 | Publication | Small | Abbreviated Journal | Small |
Volume | Issue | Pages | 2102348 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Environmental conditions during real-world application of bimetallic core–shell nanoparticles (NPs) often include the use of elevated temperatures, which are known to cause elemental redistribution, in turn significantly altering the properties of these nanomaterials. Therefore, a thorough understanding of such processes is of great importance. The recently developed combination of fast electron tomography with in situ heating holders is a powerful approach to investigate heat-induced processes at the single NP level, with high spatial resolution in 3D. In combination with 3D finite-difference diffusion simulations, this method can be used to disclose the influence of various NP parameters on the diffusion dynamics in Au@Ag core–shell systems. A detailed study of the influence of heating on atomic diffusion and alloying for Au@Ag NPs with varying core morphology and crystallographic details is carried out. Whereas the core shape and aspect ratio of the NPs play a minor role, twin boundaries are found to have a strong influence on the elemental diffusion. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000673326600001 | Publication Date | 2021-07-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1613-6810 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.643 | Times cited | 8 | Open Access | OpenAccess |
Notes | The funding for this project was provided by European Research Council (ERC Consolidator Grant 815128, REALNANO) and European Commission (grant 731019, EUSMI and grant 26019, ESTEEM). This work was performed under the Maria de Maeztu Units of Excellence Programme-Grant No. MDM-2017-0720, Ministry of Science and Innovation.; sygmaSB | Approved | Most recent IF: 8.643 | ||
Call Number | EMAT @ emat @c:irua:179856 | Serial | 6804 | ||
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Author | Albrecht, W.; Arslan Irmak, E.; Altantzis, T.; Pedrazo‐Tardajos, A.; Skorikov, A.; Deng, T.‐S.; van der Hoeven, J.E.S.; van Blaaderen, A.; Van Aert, S.; Bals, S. | ||||
Title | 3D Atomic‐Scale Dynamics of Laser‐Light‐Induced Restructuring of Nanoparticles Unraveled by Electron Tomography | Type | A1 Journal article | ||
Year | 2021 | Publication | Advanced Materials | Abbreviated Journal | Adv Mater |
Volume | Issue | Pages | 2100972 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Understanding light–matter interactions in nanomaterials is crucial for optoelectronic, photonic, and plasmonic applications. Specifically, metal nanoparticles (NPs) strongly interact with light and can undergo shape transformations, fragmentation and ablation upon (pulsed) laser excitation. Despite being vital for technological applications, experimental insight into the underlying atomistic processes is still lacking due to the complexity of such measurements. Herein, atomic resolution electron tomography is performed on the same mesoporous-silica-coated gold nanorod, before and after femtosecond laser irradiation, to assess the missing information. Combined with molecular dynamics (MD) simulations based on the experimentally determined 3D atomic-scale morphology, the complex atomistic rearrangements, causing shape deformations and defect generation, are unraveled. These rearrangements are simultaneously driven by surface diffusion, facet restructuring, and strain formation, and are influenced by subtleties in the atomic distribution at the surface. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000671662000001 | Publication Date | 2021-07-11 | |
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 | 8 | Open Access | OpenAccess |
Notes | W.A. and E.A.I. contributed equally to this work. The authors acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ERC Consolidator Grants No. 815128 – REALNANO and No. 770887 – PICOMETRICS), the European Union’s Seventh Framework Programme (ERC Advanced Grant No. 291667 – HierarSACol), and the European Commission (EUSMI). W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in the Horizon2020 program (Grant 797153, SOPMEN). T.-S.D. acknowledges financial support from the National Science Foundation of China (NSFC, Grant No. 61905056). The authors also acknowledge financial support by the Research Foundation Flanders (FWO Grant G.0267.18N).; sygmaSB | Approved | Most recent IF: 19.791 | ||
Call Number | EMAT @ emat @c:irua:179781 | Serial | 6805 | ||
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Author | De wael, A.; De Backer, A.; Lobato, I.; Van Aert, S. | ||||
Title | Modelling ADF STEM images using elliptical Gaussian peaks and its effects on the quantification of structure parameters in the presence of sample tilt | Type | A1 Journal article | ||
Year | 2021 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | Issue | Pages | 113391 | ||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A small sample tilt away from a main zone axis orientation results in an elongation of the atomic columns in ADF STEM images. An often posed research question is therefore whether the ADF STEM image intensities of tilted nanomaterials should be quantified using a parametric imaging model consisting of elliptical rather than the currently used symmetrical peaks. To this purpose, simulated ADF STEM images corresponding to different amounts of sample tilt are studied using a parametric imaging model that consists of superimposed 2D elliptical Gaussian peaks on the one hand and symmetrical Gaussian peaks on the other hand. We investigate the quantification of structural parameters such as atomic column positions and scattering cross sections using both parametric imaging models. In this manner, we quantitatively study what can be gained from this elliptical model for quantitative ADF STEM, despite the increased parameter space and computational effort. Although a qualitative improvement can be achieved, no significant quantitative improvement in the estimated structure parameters is achieved by the elliptical model as compared to the symmetrical model. The decrease in scattering cross sections with increasing sample tilt is even identical for both types of parametric imaging models. This impedes direct comparison with zone axis image simulations. Nonetheless, we demonstrate how reliable atom-counting can still be achieved in the presence of small sample tilt. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000704334200001 | Publication Date | 2021-09-24 | |
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 | This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 770887 and No. 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through grants to A.D.w. and A.D.B. and projects G.0502.18N, G.0267.18N, and EOS 30489208. S.V.A. acknowledges TOP BOF funding from the University of Antwerp.; esteem3JRA; esteem3reported | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:181462 | Serial | 6810 | ||
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Author | Dingenen, F.; Blommaerts, N.; Van Hal, M.; Borah, R.; Arenas-Esteban, D.; Lenaerts, S.; Bals, S.; Verbruggen, S.W. | ||||
Title | Layer-by-Layer-Stabilized Plasmonic Gold-Silver Nanoparticles on TiO2: Towards Stable Solar Active Photocatalysts | Type | A1 Journal article | ||
Year | 2021 | Publication | Nanomaterials | Abbreviated Journal | Nanomaterials-Basel |
Volume | 11 | Issue | 10 | Pages | 2624 |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | To broaden the activity window of TiO2, a broadband plasmonic photocatalyst has been designed and optimized. This plasmonic ‘rainbow’ photocatalyst consists of TiO2 modified with gold–silver composite nanoparticles of various sizes and compositions, thus inducing a broadband interaction with polychromatic solar light. However, these nanoparticles are inherently unstable, especially due to the use of silver. Hence, in this study the application of the layer-by-layer technique is introduced to create a protective polymer shell around the metal cores with a very high degree of control. Various TiO2 species (pure anatase, PC500, and P25) were loaded with different plasmonic metal loadings (0–2 wt %) in order to identify the most solar active composite materials. The prepared plasmonic photocatalysts were tested towards stearic acid degradation under simulated sunlight. From all materials tested, P25 + 2 wt % of plasmonic ‘rainbow’ nanoparticles proved to be the most promising (56% more efficient compared to pristine P25) and was also identified as the most cost-effective. Further, 2 wt % of layer-by-layer-stabilized ‘rainbow’ nanoparticles were loaded on P25. These layer-by-layer-stabilized metals showed superior stability under a heated oxidative atmosphere, as well as in a salt solution. Finally, the activity of the composite was almost completely retained after 1 month of aging, while the nonstabilized equivalent lost 34% of its initial activity. This work shows for the first time the synergetic application of a plasmonic ‘rainbow’ concept and the layer-by-layer stabilization technique, resulting in a promising solar active, and long-term stable photocatalyst. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000712759800001 | Publication Date | 2021-10-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2079-4991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.553 | Times cited | 7 | Open Access | OpenAccess |
Notes | Research was funded by Research Foundation—Flanders (FWO), FN 700300001— Aspirant F. Dingenen. | Approved | Most recent IF: 3.553 | ||
Call Number | EMAT @ emat @c:irua:183281 | Serial | 6812 | ||
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Author | Esteban, D.A.; Vanrompay, H.; Skorikov, A.; Béché, A.; Verbeeck, J.; Freitag, B.; Bals, S. | ||||
Title | Fast electron low dose tomography for beam sensitive materials | Type | A1 Journal article | ||
Year | 2021 | Publication | Microscopy And Microanalysis | Abbreviated Journal | Microsc Microanal |
Volume | 27 | Issue | S1 | Pages | 2116-2118 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2021-07-30 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1431-9276 | ISBN | Additional Links | UA library record | |
Impact Factor | 1.891 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 1.891 | |||
Call Number | EMAT @ emat @c:irua:183278 | Serial | 6813 | ||
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Author | Gorbanev, Y.; Engelmann, Y.; van’t Veer, K.; Vlasov, E.; Ndayirinde, C.; Yi, Y.; Bals, S.; Bogaerts, A. | ||||
Title | Al2O3-Supported Transition Metals for Plasma-Catalytic NH3 Synthesis in a DBD Plasma: Metal Activity and Insights into Mechanisms | Type | A1 Journal article | ||
Year | 2021 | Publication | Catalysts | Abbreviated Journal | Catalysts |
Volume | 11 | Issue | 10 | Pages | 1230 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Movement Antwerp (MOVANT) | ||||
Abstract | N2 fixation into NH3 is one of the main processes in the chemical industry. Plasma catalysis is among the environmentally friendly alternatives to the industrial energy-intensive Haber-Bosch process. However, many questions remain open, such as the applicability of the conventional catalytic knowledge to plasma. In this work, we studied the performance of Al2O3-supported Fe, Ru, Co and Cu catalysts in plasma-catalytic NH3 synthesis in a DBD reactor. We investigated the effects of different active metals, and different ratios of the feed gas components, on the concentration and production rate of NH3, and the energy consumption of the plasma system. The results show that the trend of the metal activity (common for thermal catalysis) does not appear in the case of plasma catalysis: here, all metals exhibited similar performance. These findings are in good agreement with our recently published microkinetic model. This highlights the virtual independence of NH3 production on the metal catalyst material, thus validating the model and indicating the potential contribution of radical adsorption and Eley-Rideal reactions to the plasma-catalytic mechanism of NH3 synthesis. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000715656300001 | Publication Date | 2021-10-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2073-4344 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.082 | Times cited | 19 | Open Access | OpenAccess |
Notes | Catalisti, Moonshot P2C ; Research Foundation – Flanders, GoF9618n ; European Research Council, 810182 SCOPE 815128 REALNANO ; sygmaSB | Approved | Most recent IF: 3.082 | ||
Call Number | EMAT @ emat @c:irua:183279 | Serial | 6815 | ||
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Author | Prabhakara, V.; Nuytten, T.; Bender, H.; Vandervorst, W.; Bals, S.; Verbeeck, J. | ||||
Title | Linearized radially polarized light for improved precision in strain measurements using micro-Raman spectroscopy | Type | A1 Journal article | ||
Year | 2021 | Publication | Optics Express | Abbreviated Journal | Opt Express |
Volume | 29 | Issue | 21 | Pages | 34531 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Strain engineering in semiconductor transistor devices has become vital in the semiconductor industry due to the ever-increasing need for performance enhancement at the nanoscale. Raman spectroscopy is a non-invasive measurement technique with high sensitivity to mechanical stress that does not require any special sample preparation procedures in comparison to characterization involving transmission electron microscopy (TEM), making it suitable for inline strain measurement in the semiconductor industry. Indeed, at present, strain measurements using Raman spectroscopy are already routinely carried out in semiconductor devices as it is cost effective, fast and non-destructive. In this paper we explore the usage of linearized radially polarized light as an excitation source, which does provide significantly enhanced accuracy and precision as compared to linearly polarized light for this application. Numerical simulations are done to quantitatively evaluate the electric field intensities that contribute to this enhanced sensitivity. We benchmark the experimental results against TEM diffraction-based techniques like nano-beam diffraction and Bessel diffraction. Differences between both approaches are assigned to strain relaxation due to sample thinning required in TEM setups, demonstrating the benefit of Raman for nondestructive inline testing. | ||||
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Language | Wos | 000708940500144 | Publication Date | 2021-10-11 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1094-4087 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.307 | Times cited | 2 | Open Access | OpenAccess |
Notes | Horizon 2020 Framework Programme, 823717 – ESTEEM3 ; GOA project, “Solarpaint” ; Herculesstichting;; esteem3jra; esteem3reported; | Approved | Most recent IF: 3.307 | ||
Call Number | EMAT @ emat @c:irua:182472 | Serial | 6816 | ||
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Author | Hudry, D.; De Backer, A.; Popescu, R.; Busko, D.; Howard, I.A.; Bals, S.; Zhang, Y.; Pedrazo‐Tardajos, A.; Van Aert, S.; Gerthsen, D.; Altantzis, T.; Richards, B.S. | ||||
Title | Interface Pattern Engineering in Core‐Shell Upconverting Nanocrystals: Shedding Light on Critical Parameters and Consequences for the Photoluminescence Properties | Type | A1 Journal article | ||
Year | 2021 | Publication | Small | Abbreviated Journal | Small |
Volume | Issue | Pages | 2104441 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Advances in controlling energy migration pathways in core-shell lanthanide (Ln)-based hetero-nanocrystals (HNCs) have relied heavily on assumptions about how optically active centers are distributed within individual HNCs. In this article, it is demonstrated that different types of interface patterns can be formed depending on shell growth conditions. Such interface patterns are not only identified but also characterized with spatial resolution ranging from the nanometer- to the atomic-scale. In the most favorable cases, atomic-scale resolved maps of individual particles are obtained. It is also demonstrated that, for the same type of core-shell architecture, the interface pattern can be engineered with thicknesses of just 1 nm up to several tens of nanometers. Total alloying between the core and shell domains is also possible when using ultra-small particles as seeds. Finally, with different types of interface patterns (same architecture and chemical composition of the core and shell domains) it is possible to modify the output color (yellow, red, and green-yellow) or change (improvement or degradation) the absolute upconversion quantum yield. The results presented in this article introduce an important paradigm shift and pave the way toward the emergence of a new generation of core-shell Ln-based HNCs with better control over their atomic-scale organization. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000710758000001 | Publication Date | 2021-10-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1613-6810 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.643 | Times cited | 17 | Open Access | OpenAccess |
Notes | The authors would like to acknowledge the financial support provided by the Helmholtz Recruitment Initiative Fellowship (B.S.R.) and the Helmholtz Association's Research Field Energy (Materials and Technologies for the Energy Transition program, Topic 1 Photovoltaics and Wind Energy). The authors would like to thank the Karlsruhe Nano Micro Facility (KNMF) for STEM access. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (Grant agreement no. 770887 PICOMETRICS to S.V.A. and Grant agreement no. 815128 REALNANO to S.B.). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through Projects no. G.0502.18N, G.0267.18N, and a postdoctoral grant to A.D.B. T.A. acknowledges funding from the University of Antwerp Research fund (BOF). This project had received funding (EUSMI proposal #E181100205) from the European Union's Horizon 2020 Research and Innovation Programme under Grant agreement no 731019 (EUSMI). D.H. would like to thank “CGFigures” for helpful tutorials on 3D graphics with Blender.; sygmaSB | Approved | Most recent IF: 8.643 | ||
Call Number | EMAT @ emat @c:irua:183285 | Serial | 6817 | ||
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Author | Velazco, A.; Béché, A.; Jannis, D.; Verbeeck, J. | ||||
Title | Reducing electron beam damage through alternative STEM scanning strategies, Part I: Experimental findings | Type | A1 Journal article | ||
Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 232 | Issue | Pages | 113398 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The highly energetic electrons in a transmission electron microscope (TEM) can alter or even completely destroy the structure of samples before sufficient information can be obtained. This is especially problematic in the case of zeolites, organic and biological materials. As this effect depends on both the electron beam and the sample and can involve multiple damage pathways, its study remained difficult and is plagued with irreproducibility issues, circumstantial evidence, rumors, and a general lack of solid data. Here we take on the experimental challenge to investigate the role of the STEM scan pattern on the damage behavior of a commercially available zeolite sample with the clear aim to make our observations as reproducible as possible. We make use of a freely programmable scan engine that gives full control over the tempospatial distribution of the electron probe on the sample and we use its flexibility to obtain multiple repeated experiments under identical conditions comparing the difference in beam damage between a conventional raster scan pattern and a newly proposed interleaved scan pattern that provides exactly the same dose and dose rate and visits exactly the same scan points. We observe a significant difference in beam damage for both patterns with up to 11 % reduction in damage (measured from mass loss). These observations demonstrate without doubt that electron dose, dose rate and acceleration voltage are not the only parameters affecting beam damage in (S)TEM experiments and invite the community to rethink beam damage as an unavoidable consequence of applied electron dose. | ||||
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Language | Wos | 000714819200002 | Publication Date | 2021-10-02 | |
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 | 18 | Open Access | OpenAccess |
Notes | A.V., D.J., A.B. and J.V. acknowledge funding from FWO project G093417N (’Compressed sensing enabling low dose imaging in transmission electron microscopy’) and G042920N (’Coincident event detection for advanced spectroscopy in transmission electron microscopy’). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 ESTEEM3. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from GOA project “Solarpaint” of the University of Antwerp.; JRA; reported | Approved | Most recent IF: 2.2 | ||
Call Number | EMAT @ emat @c:irua:183282 | Serial | 6818 | ||
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Author | Arslan Irmak, E.; Liu, P.; Bals, S.; Van Aert, S. | ||||
Title | 3D Atomic Structure of Supported Metallic Nanoparticles Estimated from 2D ADF STEM Images: A Combination of Atom – Counting and a Local Minima Search Algorithm | Type | A1 Journal article | ||
Year | 2021 | Publication | Small methods | Abbreviated Journal | Small Methods |
Volume | Issue | Pages | 2101150 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Determining the three-dimensional (3D) atomic structure of nanoparticles (NPs) is critical to understand their structure-dependent properties. It is hereby important to perform such analyses under conditions relevant for the envisioned application. Here, we investigate the 3D structure of supported Au NPs at high temperature, which is of importance to understand their behavior during catalytic reactions. To overcome limitations related to conventional high-resolution electron tomography at high temperature, 3D characterization of NPs with atomic resolution has been performed by applying atom-counting using atomic resolution annular darkfield scanning transmission electron microscopy (ADF STEM) images followed by structural relaxation. However, at high temperatures, thermal displacements, which affect the ADF STEM intensities, should be taken into account. Moreover, it is very likely that the structure of a NP investigated at elevated temperature deviates from a ground state configuration, which is difficult to determine using purely computational energy minimization approaches. In this paper, we therefore propose an optimized approach using an iterative local minima search algorithm followed by molecular dynamics (MD) structural relaxation of candidate structures associated with each local minimum. In this manner, it becomes possible to investigate the 3D atomic structure of supported NPs, which may deviate from their ground state configuration. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000716511600001 | Publication Date | 2021-11-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2366-9608 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 12 | Open Access | OpenAccess | |
Notes | This work was supported by the European Research Council (Grant 815128 REALNANO to SB, Grant 770887 PICOMETRICS to SVA, Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0267.18N, G.0502.18N, G.0346.21N).; sygmaSB; esteem3jra; esteem3reported | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @c:irua:183289 | Serial | 6820 | ||
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Author | Jannis, D.; Müller-Caspary, K.; Béché, A.; Verbeeck, J. | ||||
Title | Coincidence Detection of EELS and EDX Spectral Events in the Electron Microscope | Type | A1 Journal article | ||
Year | 2021 | Publication | Applied Sciences-Basel | Abbreviated Journal | Appl Sci-Basel |
Volume | 11 | Issue | 19 | Pages | 9058 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Recent advances in the development of electron and X-ray detectors have opened up the possibility to detect single events from which its time of arrival can be determined with nanosecond resolution. This allows observing time correlations between electrons and X-rays in the transmission electron microscope. In this work, a novel setup is described which measures individual events using a silicon drift detector and digital pulse processor for the X-rays and a Timepix3 detector for the electrons. This setup enables recording time correlation between both event streams while at the same time preserving the complete conventional electron energy loss (EELS) and energy dispersive X-ray (EDX) signal. We show that the added coincidence information improves the sensitivity for detecting trace elements in a matrix as compared to conventional EELS and EDX. Furthermore, the method allows the determination of the collection efficiencies without the use of a reference sample and can subtract the background signal for EELS and EDX without any prior knowledge of the background shape and without pre-edge fitting region. We discuss limitations in time resolution arising due to specificities of the silicon drift detector and discuss ways to further improve this aspect. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000710160300001 | Publication Date | 2021-09-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2076-3417 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.679 | Times cited | 9 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G042920 ; Horizon 2020 Framework Programme, 101017720 ; Helmholtz-Fonds, VH-NG-1317 ; | Approved | Most recent IF: 1.679 | ||
Call Number | EMAT @ emat @c:irua:183336 | Serial | 6821 | ||
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Author | Lebedev, N.; Stehno, M.; Rana, A.; Reith, P.; Gauquelin, N.; Verbeeck, J.; Hilgenkamp, H.; Brinkman, A.; Aarts, J. | ||||
Title | Gate-tuned anomalous Hall effect driven by Rashba splitting in intermixed LaAlO3/GdTiO3/SrTiO3 | Type | A1 Journal article | ||
Year | 2021 | Publication | Scientific Reports | Abbreviated Journal | Sci Rep-Uk |
Volume | 11 | Issue | 1 | Pages | 10726 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The Anomalous Hall Effect (AHE) is an important quantity in determining the properties and understanding the behaviour of the two-dimensional electron system forming at the interface of SrTiO<sub>3</sub>-based oxide heterostructures. The occurrence of AHE is often interpreted as a signature of ferromagnetism, but it is becoming more and more clear that also paramagnets may contribute to AHE. We studied the influence of magnetic ions by measuring intermixed LaAlO<sub>3</sub>/GdTiO<sub>3</sub>/SrTiO<sub>3</sub>at temperatures below 10 K. We find that, as function of gate voltage, the system undergoes a Lifshitz transition while at the same time an onset of AHE is observed. However, we do not observe clear signs of ferromagnetism. We argue the AHE to be due to the change in Rashba spin-orbit coupling at the Lifshitz transition and conclude that also paramagnetic moments which are easily polarizable at low temperatures and high magnetic fields lead to the presence of AHE, which needs to be taken into account when extracting carrier densities and mobilities. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000658820100014 | Publication Date | 2021-05-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2045-2322 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.259 | Times cited | 5 | Open Access | OpenAccess |
Notes | J.V. and N.G. acknowledge funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and the European Union’s horizon 2020 research and innovation programme ESTEEM3 under grant agreement 823717. The Qu-Ant-EM microscope used in this study was partly funded by the Hercules fund from the Flemish Government.; esteem3TA; esteem3reported | Approved | Most recent IF: 4.259 | ||
Call Number | EMAT @ emat @c:irua:179608 | Serial | 6822 | ||
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Author | Herzog, M.J.; Gauquelin, N.; Esken, D.; Verbeeck, J.; Janek, J. | ||||
Title | Increased Performance Improvement of Lithium-Ion Batteries by Dry Powder Coating of High-Nickel NMC with Nanostructured Fumed Ternary Lithium Metal Oxides | Type | A1 Journal article | ||
Year | 2021 | Publication | ACS applied energy materials | Abbreviated Journal | ACS Appl. Energy Mater. |
Volume | 4 | Issue | 9 | Pages | 8832-8848 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Dry powder coating is an effective approach to protect the surfaces of layered cathode active materials (CAMs) in lithium-ion batteries. Previous investigations indicate an incorporation of lithium ions in fumed Al2O3, ZrO2, and TiO2 coatings on LiNi0.7Mn0.15Co0.15O2 during cycling, improving the cycling performance. Here, this coating approach is transferred for the first time to fumed ternary LiAlO2, Li4Zr3O8, and Li4Ti5O12 and directly compared with their lithium-free equivalents. All materials could be processed equally and their nanostructured small aggregates accumulate on the CAM surfaces to quite homogeneous coating layers with a certain porosity. The LiNixMnyCozO2 (NMC) coated with lithium-containing materials shows an enhanced improvement in overall capacity, capacity retention, rate performance, and polarization behavior during cycling, compared to their lithium-free analogues. The highest rate performance was achieved with the fumed ZrO2 coating, while the best long-term cycling stability with the highest absolute capacity was obtained for the fumed LiAlO2-coated NMC. The optimal coating agent for NMC to achieve a balanced system is fumed Li4Ti5O12, providing a good compromise between high rate capability and good capacity retention. The coating agents prevent CAM particle cracking and degradation in the order LiAlO2 ≈ Al2O3 > Li4Ti5O12 > Li4Zr3O8 > ZrO2 > TiO2. A schematic model for the protection and electrochemical performance enhancement of high-nickel NMC with fumed metal oxide coatings is sketched. It becomes apparent that physical and chemical characteristics of the coating significantly influence the performance of NMC. A high degree of coating-layer porosity is favorable for the rate capability, while a high coverage of the surface, especially in vulnerable grain boundaries, enhances the long-term cycling stability and improves the cracking behavior of NMCs. While zirconium-containing coatings possess the best chemical properties for high rate performances, aluminum-containing coatings feature a superior chemical nature to protect high-nickel NMCs. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000703338600018 | Publication Date | 2021-09-27 | |
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 | 15 | Open Access | OpenAccess | |
Notes | For his support in scanning electron microscopy analysis, the authors thank Erik Peldszus. N. G. and J. V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and from the Flemish Research Fund (FWO) project G0F1320N. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @c:irua:183949 | Serial | 6823 | ||
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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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Corporate Author | Thesis | ||||
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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Corporate Author | Thesis | ||||
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 | 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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Corporate Author | Thesis | ||||
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 | 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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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
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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Publisher | Place of Publication | Editor | |||
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 | ||
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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. | ||||
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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 | ||
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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. | ||||
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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 | ||
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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 | ||||
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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 | Not_Open_Access | ||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ admin @ c:irua:180615 | Serial | 6838 | ||
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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. | ||||
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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 | ||
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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. | ||||
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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 | ||
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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. | ||||
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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 | ||
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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. | ||||
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Language | Wos | Publication Date | |||
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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 | ||
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