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Author Khalilov, U.; Bogaerts, A.; Xu, B.; Kato, T.; Kaneko, T.; Neyts, E.C.
Title How the alignment of adsorbed ortho H pairs determines the onset of selective carbon nanotube etching Type A1 Journal article
Year 2017 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 9 Issue 9 Pages 1653-1661
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Unlocking the enormous technological potential of carbon nanotubes strongly depends on our ability to specifically produce metallic or semiconducting tubes. While selective etching of both has already been demonstrated, the underlying reasons, however, remain elusive as yet. We here present computational and experimental evidence on the operative mechanisms at the atomic scale. We demonstrate that during the adsorption of H atoms and their coalescence, the adsorbed ortho hydrogen pairs on single-walled carbon nanotubes induce higher shear stresses than axial stresses, leading to the elongation of HC–CH bonds as a function of their alignment with the tube chirality vector, which we denote as the γ-angle. As a result, the C–C cleavage occurs more rapidly in nanotubes containing ortho H-pairs with a small γ-angle. This phenomenon can explain the selective etching of small-diameter semiconductor nanotubes with a similar curvature. Both theoretical and experimental results strongly indicate the important role of the γ-angle in the selective etching mechanisms of carbon nanotubes, in addition to the nanotube curvature and metallicity effects and lead us to clearly understand the onset of selective synthesis/removal of CNT-based materials.
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Publisher Place of Publication Editor
Language Wos 000395422800036 Publication Date 2016-12-19
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 6 Open Access OpenAccess
Notes U. K. gratefully acknowledges financial support from the Fund of Scientific Research Flanders (FWO), Belgium (Grant No. 12M1315N). This work was also supported in part by Grant-in- Aid for Young Scientists A (Grant No. 25706028), Grant-in-Aid for Scientific Research on Innovative Areas (Grant No. 26107502) from JSPS KAKENHI. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. The authors also thank Prof. A. C. T. van Duin for sharing the ReaxFF code and J. Razzokov for his assistance to perform the DFT calculations. Approved (down) Most recent IF: 7.367
Call Number PLASMANT @ plasmant @ c:irua:140091 Serial 4417
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Author De Backer, A.; Jones, L.; Lobato, I.; Altantzis, T.; Goris, B.; Nellist, P.D.; Bals, S.; Van Aert, S.
Title Three-dimensional atomic models from a single projection using Z-contrast imaging: verification by electron tomography and opportunities Type A1 Journal article
Year 2017 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 9 Issue 9 Pages 8791-8798
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In order to fully exploit structure–property relations of nanomaterials, three-dimensional (3D) characterization at the atomic scale is often required. In recent years, the resolution of electron tomography has reached the atomic scale. However, such tomography typically requires several projection images demanding substantial electron dose. A newly developed alternative circumvents this by counting the number of atoms across a single projection. These atom counts can be used to create an initial atomic model with which an energy minimization can be applied to obtain a relaxed 3D reconstruction of the nanoparticle. Here, we compare, at the atomic scale, this single projection reconstruction approach with tomography and find an excellent agreement. This new approach allows for the characterization of beam-sensitive materials or where the acquisition of a tilt series is impossible. As an example, the utility is illustrated by the 3D atomic scale characterization of a nanodumbbell on an in situ heating holder of limited tilt range.
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Publisher Place of Publication Editor
Language Wos 000404614700031 Publication Date 2017-06-09
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 33 Open Access OpenAccess
Notes The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N, G.0368.15N, and WO.010.16N) and postdoctoral grants to T. Altantzis, A. De Backer, and B. Goris. S. Bals acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078). Funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiatieve-I3) is acknowledged. The authors would also like to thank Luis Liz-Marzán, Marek Grzelczak, and Ana Sánchez-Iglesias for sample provision. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @ c:irua:144436UA @ admin @ c:irua:144436 Serial 4617
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Author Schnepf, M.J.; Mayer, M.; Kuttner, C.; Tebbe, M.; Wolf, D.; Dulle, M.; Altantzis, T.; Formanek, P.; Förster, S.; Bals, S.; König, T.A.F.; Fery, A.
Title Nanorattles with tailored electric field enhancement Type A1 Journal article
Year 2017 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 9 Issue 9 Pages 9376-9385
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanorattles are metallic core–shell particles with core and shell separated by a dielectric spacer. These

nanorattles have been identified as a promising class of nanoparticles, due to their extraordinary high

electric-field enhancement inside the cavity. Limiting factors are reproducibility and loss of axial symmetry

owing to the movable metal core; movement of the core results in fluctuation of the nanocavity dimensions

and commensurate variations in enhancement factor. We present a novel synthetic approach for

the robust fixation of the central gold rod within a well-defined box, which results in an axisymmetric

nanorattle. We determine the structure of the resulting axisymmetric nanorattles by advanced transmission

electron microscopy (TEM) and small-angle X-ray scattering (SAXS). Optical absorption and scattering

cross-sections obtained from UV-vis-NIR spectroscopy quantitatively agree with finite-difference

time-domain (FDTD) simulations based on the structural model derived from SAXS. The predictions of

high and homogenous field enhancement are evidenced by scanning TEM electron energy loss spectroscopy

(STEM-EELS) measurement on single-particle level. Thus, comprehensive understanding of

structural and optical properties is achieved for this class of nanoparticles, paving the way for photonic

applications where a defined and robust unit cell is crucial.
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Publisher Place of Publication Editor
Language Wos 000405387100015 Publication Date 2017-06-22
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 69 Open Access OpenAccess
Notes This study was funded by the European Research Council under grant Template-assisted assembly of METAmaterials using MECHanical instabilities (METAMECH) ERC-2012-StG 306686. This work was also supported by the Deutsche Forschungsgemeinschaft (DFG) within the Cluster of Excellence ‘Center for Advancing Electronics Dresden’ (cfaed). M. T. wants to acknowledge funding by the Elite Network of Bavaria, the Bavarian Ministry of State according to the Bavarian elite promotion act (BayEFG), as well as the Alexander von Humboldt Foundation for a Feodor-Lynen Research Fellowship. S. B. acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078) and T. A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. We thank Ken Harris from the National Research Council Canada for valuable discussion of the manuscript. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @ c:irua:144797UA @ admin @ c:irua:144797 Serial 4631
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Author Albrecht, W.; Goris, B.; Bals, S.; Hutter, E.M.; Vanmaekelbergh, D.; van Huis, M.A.; van Blaaderen, A.
Title Morphological and chemical transformations of single silica-coated CdSe/CdS nanorods upon fs-laser excitation Type A1 Journal article
Year 2017 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 9 Issue 9 Pages 4810-4818
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Radiation-induced modifications of nanostructures are of fundamental interest and constitute a viable out-of-equilibrium approach to the development of novel nanomaterials. Herein, we investigated the structural transformation of silica-coated CdSe/CdS nanorods (NRs) under femtosecond (fs) illumination. By comparing the same nanorods before and after illumination with different fluences we found that the silica-shell did not only enhance the stability of the NRs but that the confinement of the NRs also led to novel morphological and chemical transformations. Whereas uncoated CdSe/CdS nanorods were found to sublimate under such excitations the silica-coated nanorods broke into fragments which deformed towards a more spherical shape. Furthermore, CdS decomposed which led to the formation of metallic Cd, confirmed by high-resolution electron microscopy and energy dispersive X-ray spectrometry (EDX), whereby an epitaxial interface with the remaining CdS lattice was formed. Under electron beam exposure similar transformations were found to take place which we followed in situ.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000398954800022 Publication Date 2017-03-23
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 4 Open Access OpenAccess
Notes ; The authors acknowledge financial support from the European Research Council under the European Unions Seventh Framework Programme (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. The authors furthermore acknowledge financial support from the European Research Council (ERC Starting Grant 335078-COLOURATOMS and ERC Consolidator Grant 683076 NANO-INSITU). The authors also appreciate financial support from the European Union under the Seventh Framework Program (Integrated Infrastructure Initiative No. 262348 European Soft Matter Infrastructure, ESMI). This work was supported by the Flemish Fund for Scientific Research (FWO Vlaanderen) through a postdoctoral research grant to B. G. The authors furthermore thank Dave J. van den Heuvel and Hans C. Gerritsen for use of the Thorlabs powermeter. We furthermore thank Ernest van der Wee for the simulation of the confocal point spread functions. ; ecas_sara Approved (down) Most recent IF: 7.367
Call Number UA @ lucian @ c:irua:142384UA @ admin @ c:irua:142384 Serial 4670
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Author Zheng, G.; Chen, Z.; Sentosun, K.; Pérez-Juste, I.; Bals, S.; Liz-Marzán, L.M.; Pastoriza-Santos, I.; Pérez-Juste, J.; Hong, M.
Title Shape control in ZIF-8 nanocrystals and metal nanoparticles@ZIF-8 heterostructures Type A1 Journal article
Year 2017 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 9 Issue 9 Pages 16645-16651
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Shape control in metal-organic frameworks still remains a challenge. We propose a strategy based on the capping agent modulator method to control the shape of ZIF-8 nanocrystals. This approach requires the use of a surfactant, cetyltrimethylammonium bromide (CTAB), and a second capping agent, tris(hydroxymethyl)aminomethane (TRIS), to obtain ZIF-8 nanocrystals with morphology control in aqueous media. Semiempirical computational simulations suggest that both shape-inducing agents adsorb onto different surface facets of ZIF-8, thereby slowing down their crystal growth rates. While CTAB molecules preferentially adsorb onto the {100} facets, leading to ZIF-8 particles with cubic morphology, TRIS preferentially stabilizes the {111} facets, inducing the formation of octahedral crystals. Interestingly, the presence of both capping agents leads to nanocrystals with irregular shapes and higher index facets, such as hexapods and burr puzzles. Additionally, the combination of ZIF-8 nanocrystals with other materials is expected to impart additional properties due to the hybrid nature of the resulting nanocomposites. In the present case, the presence of CTAB and TRIS molecules as capping agents facilitates the synthesis of metal nanoparticle@ZIF-8 nanocomposites, due to synergistic effects which could be of use in a number of applications such as catalysis, gas sensing and storage.
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Publisher Place of Publication Editor
Language Wos 000414960900015 Publication Date 2017-07-25
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 109 Open Access OpenAccess
Notes This work was supported by the Ministerio de Economía y Competitividad (MINECO, Spain), under the Grants MAT2013- 45168-R and MAT2016-77809-R. This study was also funded by the Xunta de Galicia/FEDER (ED431C 2016-048). We are grateful to the financial support from National Natural Science Foundation of China (21671010), Guangdong Science and Technology Program (2013A061401002), and Shenzhen Strategic Emerging Industries (KQCX2015032709315529, CXZZ20140419131807788). Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:145827UA @ admin @ c:irua:145827 Serial 4705
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Author Pramanik, G.; Humpolickova, J.; Valenta, J.; Kundu, P.; Bals, S.; Bour, P.; Dracinsky, M.; Cigler, P.
Title Gold nanoclusters with bright near-infrared photoluminescence Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 10 Issue 10 Pages 3792-3798
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The increase in nonradiative pathways with decreasing emission energy reduces the luminescence quantum yield (QY) of near-infrared photoluminescent (NIR PL) metal nanoclusters. Efficient surface ligand chemistry can significantly improve the luminescence QY of NIR PL metal nanoclusters. In contrast to the widely reported but modestly effective thiolate ligand-to-metal core charge transfer, we show that metal-to-ligand charge transfer (MLCT) can be used to greatly enhance the luminescence QY of NIR PL gold nanoclusters (AuNCs). We synthesized water-soluble and colloidally stable NIR PL AuNCs with unprecedentedly high QY (similar to 25%) upon introduction of triphenylphosphonium moieties into the surface capping layer. By using a combination of spectroscopic and theoretical methods, we provide evidence for gold core-to-ligand charge transfer occurring in AuNCs. We envision that this work can stimulate the development of these unusually bright AuNCs for promising optoelectronic, bioimaging, and other applications.
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Publisher Place of Publication Cambridge Editor
Language Wos 000426148500026 Publication Date 2018-01-08
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 97 Open Access OpenAccess
Notes ; The authors acknowledge support from the GACR project Nr. 18-12533S. J. V. acknowledges funding from the Ministry of Education, Youth and Sports of the Czech Republic via the V4+Japan project No. 8F15001 (cofinanced by the International Visegrad Fund). P. B. acknowledges GACR project No. 16-05935S and Ministry of Education, Youth and Sports of the Czech Republic project No. LTC17012. ; Approved (down) Most recent IF: 7.367
Call Number UA @ lucian @ c:irua:149901UA @ admin @ c:irua:149901 Serial 4935
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Author Lombardo, J.; Jelić, Ž.L.; Baumans, X.D.A.; Scheerder, J.E.; Nacenta, J.P.; Moshchalkov, V.V.; Van de Vondel, J.; Kramer, R.B.G.; Milošević, M.V.; Silhanek, A.V.
Title In situ tailoring of superconducting junctions via electro-annealing Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 10 Issue 4 Pages 1987-1996
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We demonstrate the in situ engineering of superconducting nanocircuitry by targeted modulation of material properties through high applied current densities. We show that the sequential repetition of such customized electro-annealing in a niobium (Nb) nanoconstriction can broadly tune the superconducting critical temperature T-c and the normal-state resistance R-n in the targeted area. Once a sizable R-n is reached, clear magneto-resistance oscillations are detected along with a Fraunhofer-like field dependence of the critical current, indicating the formation of a weak link but with further adjustable characteristics. Advanced Ginzburg-Landau simulations fully corroborate this picture, employing the detailed parametrization from the electrical characterization and high resolution electron microscope images of the region within the constriction where the material has undergone amorphization by electro-annealing.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000423355300049 Publication Date 2017-12-29
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 23 Open Access
Notes ; The authors thank the Fonds de la Recherche Scientifique – FNRS, the ARC grant 13/18-08 for Concerted Research Actions, financed by the French Community of Belgium (Wallonia-Brussels Federation), the Research Foundation – Flanders (FWO-Vlaanderen) and the COST action NanoCoHybri (CA16218). The work is also suppported by Methusalem Funding by the Flemish Government. J. Lombardo acknowledges support from F. R. S.-FNRS (FRIA Research Fellowship). The LANEF framework (ANR-10-LABX-51-01) and the Nanoscience Foundation are acknowledged for their support with mutualized infrastructure. The work of A. V. Silhanek is partially supported by PDR T.0106.16 of the F. R. S.-FNRS. The authors thank the ULg Microscopy facility CAREM for part of the SEM investigations. ; Approved (down) Most recent IF: 7.367
Call Number UA @ lucian @ c:irua:149315UA @ admin @ c:irua:149315 Serial 4937
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Author Claes, N.; Asapu, R.; Blommaerts, N.; Verbruggen, S.W.; Lenaerts, S.; Bals, S.
Title Characterization of silver-polymer core–shell nanoparticles using electron microscopy Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 10 Issue 10 Pages 9186-9191
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract Silver-polymer core–shell nanoparticles show interesting optical properties, making them widely applicable in the field of plasmonics. The uniformity, thickness and homogeneity of the polymer shell will affect the properties of the system which makes a thorough structural characterization of these core–shell silver-polymer nanoparticles of great importance. However, visualizing the shell and the particle simultaneously is far from straightforward due to the sensitivity of the polymer shell towards the electron beam. In this study, we use different 2D and 3D electron microscopy techniques to investigate different structural aspects of the polymer coating.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000437007700028 Publication Date 2018-04-16
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 11 Open Access OpenAccess
Notes N. C. and S. B. acknowledge financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS) and from the FWO through project funding (G038116N). R. A. and S. L. acknowledge the Research Foundation Flanders (FWO) for financial support. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ECAS_Sara Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:151290UA @ admin @ c:irua:151290 Serial 4959
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Author Rizzo, F.; Augieri, A.; Kursumovic, A.; Bianchetti, M.; Opherden, L.; Sieger, M.; Huehne, R.; Haenisch, J.; Meledin, A.; Van Tendeloo, G.; MacManus-Driscoll, J.L.; Celentano, G.
Title Pushing the limits of applicability of REBCO coated conductor films through fine chemical tuning and nanoengineering of inclusions Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 10 Issue 17 Pages 8187-8195
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract An outstanding current carrying performance (namely critical current density, J(c)) over a broad temperature range of 10-77 K for magnetic fields up to 12 T is reported for films of YBa2Cu3O7-x with Ba2Y(Nb,Ta)O-6 inclusion pinning centres (YBCO-BYNTO) and thicknesses in the range of 220-500 nm. J(c) values of 10 MA cm(-2) were measured at 30 K – 5 T and 10 K – 9 T with a corresponding maximum of the pinning force density at 10 K close to 1 TN m(-3). The system is very flexible regarding properties and microstructure tuning, and the growth window for achieving a particular microstructure is wide, which is very important for industrial processing. Hence, the dependence of J(c) on the magnetic field angle was readily controlled by fine tuning the pinning microstructure. Transmission electron microscopy (TEM) analysis highlighted that higher growth rates induce more splayed and denser BYNTO nanocolumns with a matching field as high as 5.2 T. Correspondingly, a strong peak at the B||c-axis is noticed when the density of vortices is lower than the nanocolumn density. YBCO-BYNTO is a very robust and reproducible composite system for high-current coated conductors over an extended range of magnetic fields and temperatures.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000432261400037 Publication Date 2018-03-26
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 9 Open Access OpenAccess
Notes ; This work was partially financially supported by EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7/ 2007-2013) under Grant Agreement No. 280432. This work has been partially carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 under grant agreement no. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. ; Approved (down) Most recent IF: 7.367
Call Number UA @ lucian @ c:irua:151520 Serial 5038
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Author Kong, X.; Li, L.; Leenaerts, O.; Wang, W.; Liu, X.-J.; Peeters, F.M.
Title Quantum anomalous Hall effect in a stable 1T-YN2 monolayer with a large nontrivial bandgap and a high Chern number Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 10 Issue 17 Pages 8153-8161
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The quantum anomalous Hall (QAH) effect is a topologically nontrivial phase, characterized by a non-zero Chern number defined in the bulk and chiral edge states in the boundary. Using first-principles calculations, we demonstrate the presence of the QAH effect in a 1T-YN2 monolayer, which was recently predicted to be a Dirac half metal without spin-orbit coupling (SOC). We show that the inclusion of SOC opens up a large nontrivial bandgap of nearly 0.1 eV in the electronic band structure. This results in the nontrivial bulk topology, which is confirmed by the calculation of Berry curvature, anomalous Hall conductance and the presence of chiral edge states. Remarkably, a QAH phase of high Chern number C = 3 is found, and there are three corresponding gapless chiral edge states emerging inside the bulk gap. Different substrates are also chosen to study the possible experimental realization of the 1T-YN2 monolayer, while retaining its nontrivial topological properties. Our results open a new avenue in searching for QAH insulators with high temperature and high Chern numbers, which can have nontrivial practical applications.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000432261400033 Publication Date 2018-03-28
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 28 Open Access
Notes ; This work was supported by the Ministry of Science and Technology of China (MOST) (Grant No. 2016YFA0301604), the National Natural Science Foundation of China (NSFC) (No. 11574008), the Thousand-Young-Talent Program of China, the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl) and the FLAG-ERA project TRANS 2D TMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government department EWI, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. W. Wang acknowledges financial support from the National Natural Science Foundation of China (Grant No. 11404214) and the China Scholarship Council (CSC). ; Approved (down) Most recent IF: 7.367
Call Number UA @ lucian @ c:irua:151519UA @ admin @ c:irua:151519 Serial 5040
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Author Barreca, D.; Gri, F.; Gasparotto, A.; Carraro, G.; Bigiani, L.; Altantzis, T.; Žener, B.; Lavrenčič Štangar, U.; Alessi, B.; Padmanaban, D.B.; Mariotti, D.; Maccato, C.
Title Multi-functional MnO2nanomaterials for photo-activated applications by a plasma-assisted fabrication route Type A1 Journal article
Year 2019 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 11 Issue 1 Pages 98-108
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Supported MnO2-based nanomaterials were fabricated on fluorine-doped tin oxide substrates by plasma enhanced-chemical vapor deposition (PE-CVD) between 100 °C and 400 °C, starting from a fluorinated Mn(II) diamine diketonate precursor. Growth experiments yielded -MnO2 nanosystems with hierarchical morphology tuneable from dendritic structures to quasi-1D nanosystems as a function of growth temperature, whose variation enabled also a concomitant tailoring of the system fluorine content, and of the optical absorption and band gap. Preliminary photocatalytic tests were aimed at the investigation of photoinduced hydrophilic (PH) and solid phase photocatalytic (PC) performances of the present nanomaterials, as well as at the photodegradation of Plasmocorinth B azo-dye aqueous solutions. The obtained findings highlighted an attractive system photoactivity even under visible light, finely tailored by fluorine content, morphological organization and optical properties of the prepared nanostructures. The results indicate that the synthesized MnO2 nanosystems have potential applications as advanced smart materials for anti-fogging/self-cleaning end uses and water purification.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000454327500037 Publication Date 2018-10-10
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 7 Open Access OpenAccess
Notes Padova University DOR 2016–2017, P-DiSC #03BIRD2016-UNIPD projects, HERALD Cost Action MP1402 – 37831 and ACTION post-doc fellowship are acknowledged for financial support. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO). Thanks are also due to Prof. Sara Bals (EMAT, University of Antwerp, Belgium), Prof. Romana Cerc Korošec and to Dr. Lev Matoh (University of Ljubljana, Slovenia), and to Prof. Elza Bontempi (Brescia University, Italy). The work was also supported by EPSRC (award EP/R008841/1, EP/M024938/1). Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @UA @ admin @ c:irua:156388 Serial 5148
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Author Vanrompay, H.; Bladt, E.; Albrecht, W.; Béché, A.; Zakhozheva, M.; Sánchez-Iglesias, A.; Liz-Marzán, L.M.; Bals, S.
Title 3D characterization of heat-induced morphological changes of Au nanostars by fast in situ electron tomography Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 10 Issue 10 Pages 22792-22801
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A thorough understanding of the thermal stability and potential reshaping of anisotropic gold nanostars is required for various potential applications. Combination of a tomographic heating holder with fast tilt series acquisition has been used to monitor temperature-induced morphological changes of Au nanostars. The outcome of our 3D investigations can be used as an input for boundary element method simulations, enabling us to investigate the influence of reshaping on the nanostars’ plasmonic properties. Our work leads to a better understanding of the mechanism behind thermal reshaping. In addition, the approach presented here is generic and can hence be applied to a wide variety of nanoparticles made of different materials and with arbitrary morphology.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000453248100010 Publication Date 2018-11-28
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 55 Open Access OpenAccess
Notes H.V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). E.B. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020. The authors acknowledge funding from European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M. and M.Z. and MUMMERING 765604 to S.B. and M.Z.). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #335078- COLOURATOMS).; Ecas_sara Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:155718UA @ admin @ c:irua:155718 Serial 5071
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Author Tonkikh, A.A.; Tsebro, V.I.; Obraztsova, E.A.; Rybkovskiy, D.V.; Orekhov, A.S.; Kondrashov, I.I.; Kauppinen, E.I.; Chuvilin, A.L.; Obraztsova, E.D.
Title Films of filled single-wall carbon nanotubes as a new material for high-performance air-sustainable transparent conductive electrodes operating in a wide spectral range Type A1 Journal article
Year 2019 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 11 Issue 14 Pages 6755-6765
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In this paper we show the advantages of transparent high conductive films based on filled single-wall carbon nanotubes. The nanotubes with internal channels filled with acceptor molecules (copper chloride or iodine) form networks demonstrating significantly improved characteristics. Due to the charge transfer between the nanotubes and filler, the doped-nanotube films exhibit a drop in electrical sheet resistance of an order of magnitude together with a noticeable increase of film transparency in the visible and near-infrared spectral range. The thermoelectric power measurements show a significant improvement of air-stability of the nanotube network in the course of the filling procedure. For the nanotube films with an initial transparency of 87% at 514 nm and electrical sheet resistance of 862 Ohm sq(-1) we observed an improvement of transparency up to 91% and a decrease of sheet resistance down to 98 Ohm sq(-1). The combination of the nanotube synthesis technique and molecules for encapsulation has been optimized for applications in optoelectronics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000464454400024 Publication Date 2019-03-05
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 2 Open Access Not_Open_Access: Available from 06.09.2019
Notes ; The work was supported by the RFBR project 18-29-19113-mk, grant no. 311533 of Academy of Finland, Russian Federation President Program for young scientist MK-3140.2018.2. Also, the reported study was funded by RFBR and Moscow city Government according to the research project no. 19-32-70004. TEM measurements were performed with financial support from the Ministry of Science and Higher Education of the Russian Federation within the state assignment for the Federal Scientific Research Centre “Crystallography and Photonics” of the Russian Academy of Sciences. ; Approved (down) Most recent IF: 7.367
Call Number UA @ admin @ c:irua:159339 Serial 5249
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Author Yu, S.; Sankaran, K.J.; Korneychuk, S.; Verbeeck, J.; Haenen, K.; Jiang, X.; Yang, N.
Title High-performance supercabatteries using graphite@diamond nano-needle capacitor electrodes and redox electrolytes Type A1 Journal article
Year 2019 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 11 Issue 38 Pages 17939-17946
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Supercabatteries have the characteristics of supercapacitors and batteries, namely high power and energy densities as well as long cycle life. To construct them, capacitor electrodes with wide potential windows and/or redox electrolytes are required. Herein, graphite@diamond nano-needles and an aqueous solution of Fe(CN)(6)(3-/4-) are utilized as the capacitor electrode and the electrolyte, respectively. This diamond capacitor electrode has a nitrogen-doped diamond core and a nano-graphitic shell. In 0.05 M Fe(CN)(6)(3-/4-) + 1.0 M Na2SO4 aqueous solution, the fabricated supercabattery has a capacitance of 66.65 mF cm(-2) at a scan rate of 10 mV s(-1). It is stable over 10 000 charge/discharge cycles. The symmetric supercabattery device assembled using a two-electrode system possesses energy and power densities of 10.40 W h kg(-1) and 6.96 kW kg(-1), respectively. These values are comparable to those of other energy storage devices. Therefore, diamond supercabatteries are promising for many industrial applications.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000489646900036 Publication Date 2019-09-06
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 26 Open Access
Notes ; S. Yu and K. J. Sankaran contributed equally to this work. N. Yang acknowledges funding from the German Science Foundation under the project of YA344/1-1. J. Verbeeck and S. Korneychuk acknowledge the funding from the GOA project “Solarpaint” of the University of Antwerp. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. K. J. Sankaran and K. Haenen like to acknowledge the financial support of the Methusalem “NANO” network. S. Yu likes to acknowledge the financial support from fundamental research funds for the central universities (Grant No. SWU019001). ; Approved (down) Most recent IF: 7.367
Call Number UA @ admin @ c:irua:163723 Serial 5388
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Author Liu, P.; Wu, T.; Madsen, J.; Schiotz, J.; Wagner, J.B.; Hansen, T.W.
Title Transformations of supported gold nanoparticles observed by in situ electron microscopy Type A1 Journal article
Year 2019 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 11 Issue 24 Pages 11885-11891
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Oxide supported metal nanoparticles play an important role in heterogeneous catalysis. However, understanding the metal/oxide interface and their evolution under reaction conditions remains challenging. Herein, we investigate the interface between Au nanoparticles and a CeO2 substrate by environmental transmission electron microscopy with atomic resolution. We find that the Au nanoparticles have two preferential epitaxial relationships with the substrate, i.e. Type I (111)[-110]CeO2//(111)[-110]Au and Type II (111)[-110]CeO2//(111)[1-10]Au orientation relationships, where Type I is preferred. In situ observations in the presence of O-2 show that the gas can stimulate the supported Au nanoparticles to transform between these two orientations even at room temperature. Moreover, when increasing the temperature to 973 K, the transformation of an Au nanoparticle between the two orientation states and a non-crystalline state in the presence of O-2 is also observed. DFT calculations of the binding between Au and CeO2 in the two relationships are strongly influenced by the presence of oxygen vacancies. For a given position of a vacancy, there is a significant energy difference between the energy of the two types. However, for some positions, Type I is preferred, and for others, Type II, but the most favourable position of the vacancy for the two types has a very similar energy. This is consistent with the observation of both types of adhesion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000472559800049 Publication Date 2019-05-22
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
Notes ; ; Approved (down) Most recent IF: 7.367
Call Number UA @ admin @ c:irua:161313 Serial 5402
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Author Liu, P.; Arslan Irmak, E.; De Backer, A.; De wael, A.; Lobato, I.; Béché, A.; Van Aert, S.; Bals, S.
Title Three-dimensional atomic structure of supported Au nanoparticles at high temperature Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Au nanoparticles (NPs) deposited on CeO2 are extensively used as thermal catalysts since the morphology of the NPs is expected to be stable at elevated temperatures. Although it is well known that the activity of Au NPs depends on their size and surface structure, their three-dimensional (3D) structure at the atomic scale has not been completely characterized as a function of temperature. In this paper, we overcome the limitations of conventional electron tomography by combining atom counting applied to aberration-corrected scanning transmission electron microscopy images and molecular dynamics relaxation. In this manner, we are able to perform an atomic resolution 3D investigation of supported Au NPs. Our results enable us to characterize the 3D equilibrium structure of single NPs as a function of temperature. Moreover, the dynamic 3D structural evolution of the NPs at high temperatures, including surface layer jumping and crystalline transformations, has been studied.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000612999200029 Publication Date 2020-12-29
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 13 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 grants to A. D. w. and A. D. B. and project funding G.0267.18N.; sygma; esteem3JRA; esteem3reported Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:174858 Serial 6665
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Author Geerts, L.; Geerts-Claes, H.; Skorikov, A.; Vermeersch, J.; Vanbutsele, G.; Galvita, V.; Constales, D.; Chandran, C.V.; Radhakrishnan, S.; Seo, J.W.; Breynaert, E.; Bals, S.; Sree, S.P.; Martens, J.A.
Title Spherical core–shell alumina support particles for model platinum catalysts Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue 7 Pages 4221-4232
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract γ- and δ-alumina are popular catalyst support materials. Using a hydrothermal synthesis method starting from aluminum nitrate and urea in diluted solution, spherical core–shell particles with a uniform particle size of about 1 μm were synthesized. Upon calcination at 1000 °C, the particles adopted a core–shell structure with a γ-alumina core and δ-alumina shell as evidenced by 2D and 3D electron microscopy and<sup>27</sup>Al magic angle spinning nuclear magnetic resonance spectroscopy. The spherical alumina particles were loaded with Pt nanoparticles with an average size below 1 nm using the strong electrostatic adsorption method. Electron microscopy and energy dispersive X-ray spectroscopy revealed a homogeneous platinum dispersion over the alumina surface. These platinum loaded alumina spheres were used as a model catalyst for bifunctional catalysis. Physical mixtures of Pt/alumina spheres and spherical zeolite particles are equivalent to catalysts with platinum deposited on the zeolite itself facilitating the investigation of the catalyst components individually. The spherical alumina particles are very convenient supports for obtaining a homogeneous distribution of highly dispersed platinum nanoparticles. Obtaining such a small Pt particle size is challenging on other support materials such as zeolites. The here reported and well-characterized Pt/alumina spheres can be combined with any zeolite and used as a bifunctional model catalyst. This is an interesting strategy for the examination of the acid catalytic function without the interference of the supported platinum metal on the investigated acid material.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000621767000026 Publication Date 2021-01-21
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 3 Open Access OpenAccess
Notes Fonds Wetenschappelijk Onderzoek, G0A5417N G038116N ; Vlaamse regering, Methusalem ; Hercules Foundation, AKUL/13/19 ; Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:176021 Serial 6679
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Author Jalali, H.; Khoeini, F.; Peeters, F.M.; Neek-Amal, M.
Title Hydration effects and negative dielectric constant of nano-confined water between cation intercalated MXenes Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue 2 Pages 922-929
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Using electrochemical methods a profound enhancement of the capacitance of electric double layer capacitor electrodes was reported when water molecules are strongly confined into the two-dimensional slits of titanium carbide MXene nanosheets [A. Sugahara et al., Nat. Commun., 2019, 10, 850]. We study the effects of hydration on the dielectric properties of nanoconfined water and supercapacitance properties of the cation intercalated MXene. A model for the electric double layer capacitor is constructed where water molecules are strongly confined in two-dimensional slits of MXene. We report an abnormal dielectric constant and polarization of nano-confined water between MXene layers. We found that by decreasing the ionic radius of the intercalated cations and in a critical hydration shell radius the capacitance of the system increases significantly (similar or equal to 200 F g(-1)) which can be interpreted as a negative permittivity. This study builds a bridge between the fundamental understanding of the dielectric properties of nanoconfined water and the capability of using MXene films for supercapacitor technology, and in doing so provides a solid theoretical support for recent experiments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000610368100035 Publication Date 2020-12-08
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 7 Open Access Not_Open_Access
Notes ; ; Approved (down) Most recent IF: 7.367
Call Number UA @ admin @ c:irua:176141 Serial 6690
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Author Wu, L.; Kolmeijer, K.E.; Zhang, Y.; An, H.; Arnouts, S.; Bals, S.; Altantzis, T.; Hofmann, J.P.; Costa Figueiredo, M.; Hensen, E.J.M.; Weckhuysen, B.M.; van der Stam, W.
Title Stabilization effects in binary colloidal Cu and Ag nanoparticle electrodes under electrochemical CO₂ reduction conditions Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue 9 Pages 4835-4844
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Nanoparticle modified electrodes constitute an attractive way to tailor-make efficient carbon dioxide (CO2) reduction catalysts. However, the restructuring and sintering processes of nanoparticles under electrochemical reaction conditions not only impedes the widespread application of nanoparticle catalysts, but also misleads the interpretation of the selectivity of the nanocatalysts. Here, we colloidally synthesized metallic copper (Cu) and silver (Ag) nanoparticles with a narrow size distribution (<10%) and utilized them in electrochemical CO2 reduction reactions. Monometallic Cu and Ag nanoparticle electrodes showed severe nanoparticle sintering already at low overpotential of -0.8 V vs. RHE, as evidenced by ex situ SEM investigations, and potential-dependent variations in product selectivity that resemble bulk Cu (14% for ethylene at -1.3 V vs. RHE) and Ag (69% for carbon monoxide at -1.0 V vs. RHE). However, by co-deposition of Cu and Ag nanoparticles, a nanoparticle stabilization effect was observed between Cu and Ag, and the sintering process was greatly suppressed at CO2 reducing potentials (-0.8 V vs. RHE). Furthermore, by varying the Cu/Ag nanoparticle ratio, the CO2 reduction reaction (CO2RR) selectivity towards methane (maximum of 20.6% for dense Cu-2.5-Ag-1 electrodes) and C-2 products (maximum of 15.7% for dense Cu-1-Ag-1 electrodes) can be tuned, which is attributed to a synergistic effect between neighbouring Ag and Cu nanoparticles. We attribute the stabilization of the nanoparticles to the positive enthalpies of Cu-Ag solid solutions, which prevents the dissolution-redeposition induced particle growth under CO2RR conditions. The observed nanoparticle stabilization effect enables the design and fabrication of active CO2 reduction nanocatalysts with high durability.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000628024200011 Publication Date 2021-02-22
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 24 Open Access OpenAccess
Notes This work is funded by the Strategic UU-TU/e Alliance project ‘Joint Centre for Chemergy Research’ (budget holder B. M. W.). S. B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO). S. A. and T. A. acknowledge funding from the University of Antwerp Research fund (BOF). We thank Eric Hellebrand (Faculty of Geosciences, Utrecht University) for the assistance in SEM measurements. Dr Ramon Oord (ARC Chemical Building Blocks Consortium, Faculty of Science, Utrecht University) is acknowledged for assisting with the grazing incidence XRD measurements; sygma Approved (down) Most recent IF: 7.367
Call Number UA @ admin @ c:irua:176723 Serial 6737
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Author Skorikov, A.; Heyvaert, W.; Albecht, W.; Pelt, D.M.; Bals, S.
Title Deep learning-based denoising for improved dose efficiency in EDX tomography of nanoparticles Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue Pages 12242-12249
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The combination of energy-dispersive X-ray spectroscopy (EDX) and electron tomography is a powerful approach to retrieve the 3D elemental distribution in nanomaterials, providing an unprecedented level of information for complex, multi-component systems, such as semiconductor devices, as well as catalytic and plasmonic nanoparticles. Unfortunately, the applicability of EDX tomography is severely limited because of extremely long acquisition times and high electron irradiation doses required to obtain 3D EDX reconstructions with an adequate signal-to-noise ratio. One possibility to address this limitation is intelligent denoising of experimental data using prior expectations about the objects of interest. Herein, this approach is followed using the deep learning methodology, which currently demonstrates state-of-the-art performance for an increasing number of data processing problems. Design choices for the denoising approach and training data are discussed with a focus on nanoparticle-like objects and extremely noisy signals typical for EDX experiments. Quantitative analysis of the proposed method demonstrates its significantly enhanced performance in comparison to classical denoising approaches. This allows for improving the tradeoff between the reconstruction quality, acquisition time and radiation dose for EDX tomography. The proposed method is therefore especially beneficial for the 3D EDX investigation of electron beam-sensitive materials and studies of nanoparticle transformations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000671395800001 Publication Date 2021-07-08
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 11 Open Access OpenAccess
Notes Nederlandse Organisatie voor Wetenschappelijk Onderzoek, 016.Veni.192.235 ; H2020 European Research Council, 815128 ; H2020 Marie Skłodowska-Curie Actions, 797153 ; H2020 Research Infrastructures, 731019; realnano; sygmaSB Approved (down) Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:179756 Serial 6799
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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 (down) Most recent IF: 7.367
Call Number UA @ admin @ c:irua:179052 Serial 6843
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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 13 Issue 23 Pages 10462-10467
Keywords A1 Journal Article; Electron Microscopy for Materials Science (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 (<italic>τ</italic><sup>PL</sup>). This phenomenon is known as the heavy-atom effect (HAE). Here, we report the observation of increased<italic>τ</italic><sup>PL</sup>upon functionalisation of near-infrared photoluminescent gold nanoclusters with iodine. The heavy atom-mediated increase in<italic>τ</italic><sup>PL</sup>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 Publication Date 2021-05-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links
Impact Factor 7.367 Times cited 7 Open Access OpenAccess
Notes The authors acknowledge support from GACR project Nr.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 (down) Most recent IF: 7.367
Call Number EMAT @ emat @ Serial 6950
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Author Yagmurcukardes, M.; Sozen, Y.; Baskurt, M.; Peeters, F.M.; Sahin, H.
Title Interface-dependent phononic and optical properties of GeO/MoSO heterostructures Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The interface-dependent electronic, vibrational, piezoelectric, and optical properties of van der Waals heterobilayers, formed by buckled GeO (b-GeO) and Janus MoSO structures, are investigated by means of first-principles calculations. The electronic band dispersions show that O/Ge and S/O interface formations result in a type-II band alignment with direct and indirect band gaps, respectively. In contrast, O/O and S/Ge interfaces give rise to the formation of a type-I band alignment with an indirect band gap. By considering the Bethe-Salpeter equation (BSE) on top of G(0)W(0) approximation, it is shown that different interfaces can be distinguished from each other by means of the optical absorption spectra as a consequence of the band alignments. Additionally, the low- and high-frequency regimes of the Raman spectra are also different for each interface type. The alignment of the individual dipoles, which is interface-dependent, either weakens or strengthens the net dipole of the heterobilayers and results in tunable piezoelectric coefficients. The results indicate that the possible heterobilayers of b-GeO/MoSO asymmetric structures possess various electronic, optical, and piezoelectric properties arising from the different interface formations and can be distinguished by means of various spectroscopic techniques.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000738899600001 Publication Date 2021-12-09
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 5 Open Access Not_Open_Access
Notes Approved (down) Most recent IF: 7.367
Call Number UA @ admin @ c:irua:184722 Serial 6998
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Author Craig, T.M.; Kadu, A.A.; Batenburg, K.J.; Bals, S.
Title Real-time tilt undersampling optimization during electron tomography of beam sensitive samples using golden ratio scanning and RECAST3D Type A1 Journal article
Year 2023 Publication Nanoscale Abbreviated Journal
Volume 15 Issue 11 Pages 5391-5402
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Electron tomography is a widely used technique for 3D structural analysis of nanomaterials, but it can cause damage to samples due to high electron doses and long exposure times. To minimize such damage, researchers often reduce beam exposure by acquiring fewer projections through tilt undersampling. However, this approach can also introduce reconstruction artifacts due to insufficient sampling. Therefore, it is important to determine the optimal number of projections that minimizes both beam exposure and undersampling artifacts for accurate reconstructions of beam-sensitive samples. Current methods for determining this optimal number of projections involve acquiring and post-processing multiple reconstructions with different numbers of projections, which can be time-consuming and requires multiple samples due to sample damage. To improve this process, we propose a protocol that combines golden ratio scanning and quasi-3D reconstruction to estimate the optimal number of projections in real-time during a single acquisition. This protocol was validated using simulated and realistic nanoparticles, and was successfully applied to reconstruct two beam-sensitive metal–organic framework complexes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000937908900001 Publication Date 2023-02-13
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 6.7 Times cited 1 Open Access OpenAccess
Notes H2020 European Research Council, 815128 ; H2020 Marie Skłodowska-Curie Actions, 860942 ; Approved (down) Most recent IF: 6.7; 2023 IF: 7.367
Call Number EMAT @ emat @c:irua:195235 Serial 7260
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Author Smeyers, R.; Milošević, M.V.; Covaci, L.
Title Strong gate-tunability of flat bands in bilayer graphene due to moiré encapsulation between hBN monolayers Type A1 Journal article
Year 2023 Publication Nanoscale Abbreviated Journal
Volume 15 Issue 9 Pages 4561-4569
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract When using hexagonal boron-nitride (hBN) as a substrate for graphene, the resulting moire pattern creates secondary Dirac points. By encapsulating a multilayer graphene within aligned hBN sheets the controlled moire stacking may offer even richer benefits. Using advanced tight-binding simulations on atomistically-relaxed heterostructures, here we show that the gap at the secondary Dirac point can be opened in selected moire-stacking configurations, and is independent of any additional vertical gating of the heterostructure. On the other hand, gating can broadly tune the gap at the principal Dirac point, and may thereby strongly compress the first moire mini-band in width against the moire-induced gap at the secondary Dirac point. We reveal that in hBN-encapsulated bilayer graphene this novel mechanism can lead to isolated bands flatter than 10 meV under moderate gating, hence presenting a convenient pathway towards electronically-controlled strongly-correlated states on demand.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000933052600001 Publication Date 2023-02-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited Open Access OpenAccess
Notes Approved (down) Most recent IF: 6.7; 2023 IF: 7.367
Call Number UA @ admin @ c:irua:195249 Serial 7340
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Author Chinnabathini, V.C.; Dingenen, F.; Borah, R.; Abbas, I.; van der Tol, J.; Zarkua, Z.; D'Acapito, F.; Nguyen, T.H.T.; Lievens, P.; Grandjean, D.; Verbruggen, S.W.; Janssens, E.
Title Gas phase deposition of well-defined bimetallic gold-silver clusters for photocatalytic applications Type A1 Journal article
Year 2023 Publication Nanoscale Abbreviated Journal
Volume 15 Issue 14 Pages 6696-6708
Keywords A1 Journal article; Engineering sciences. Technology
Abstract Cluster beam deposition is employed for fabricating well-defined bimetallic plasmonic photocatalysts to enhance their activity while facilitating a more fundamental understanding of their properties. AuxAg1-x clusters with compositions (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1) spanning the metals' miscibility range were produced in the gas-phase and soft-landed on TiO2 P25-coated silicon wafers with an optimal coverage of 4 atomic monolayer equivalents. Electron microscopy images show that at this coverage most clusters remain well dispersed whereas EXAFS data are in agreement with the finding that the deposited clusters have an average size of ca. 5 nm and feature the same composition as the ablated alloy targets. A composition-dependant electron transfer from Au to Ag that is likely to impart chemical stability to the bimetallic clusters and protect Ag atoms against oxidation is additionally evidenced by XPS and XANES. Under simulated solar light, AuxAg1-x clusters show a remarkable composition-dependent volcano-type enhancement of their photocatalytic activity towards degradation of stearic acid, a model compound for organic fouling on surfaces. The Formal Quantum Efficiency (FQE) is peaking at the Au0.3Ag0.7 composition with a value that is twice as high as that of the pristine TiO2 P25 under solar simulator. Under UV the FQE of all compositions remains similar to that of pristine TiO2. A classical electromagnetic simulation study confirms that among all compositions Au0.3Ag0.7 features the largest near-field enhancement in the wavelength range of maximal solar light intensity, as well as sufficient individual photon energy resulting in a better photocatalytic self-cleaning activity. This allows ascribing the mechanism for photocatalysis mostly to the plasmonic effect of the bimetallic clusters through direct electron injection and near-field enhancement from the resonant cluster towards the conduction band of TiO2. These results not only demonstrate the added value of using well-defined bimetallic nanocatalysts to enhance their photocatalytic activity but also highlights the potential of the cluster beam deposition to design tailored noble metal modified photocatalytic surfaces with controlled compositions and sizes without involving potentially hazardous chemical agents.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000968631100001 Publication Date 2023-03-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited Open Access Not_Open_Access
Notes Approved (down) Most recent IF: 6.7; 2023 IF: 7.367
Call Number UA @ admin @ c:irua:196040 Serial 7988
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Author Conti, S.; Chaves, A.; Pandey, T.; Covaci, L.; Peeters, F.M.; Neilson, D.; Milošević, M.V.
Title Flattening conduction and valence bands for interlayer excitons in a moire MoS₂/WSe₂ heterobilayer Type A1 Journal article
Year 2023 Publication Nanoscale Abbreviated Journal
Volume Issue Pages 1-11
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract We explore the flatness of conduction and valence bands of interlayer excitons in MoS2/WSe2 van der Waals heterobilayers, tuned by interlayer twist angle, pressure, and external electric field. We employ an efficient continuum model where the moire pattern from lattice mismatch and/or twisting is represented by an equivalent mesoscopic periodic potential. We demonstrate that the mismatch moire potential is too weak to produce significant flattening. Moreover, we draw attention to the fact that the quasi-particle effective masses around the Gamma-point and the band flattening are reduced with twisting. As an alternative approach, we show (i) that reducing the interlayer distance by uniform vertical pressure can significantly increase the effective mass of the moire hole, and (ii) that the moire depth and its band flattening effects are strongly enhanced by accessible electric gating fields perpendicular to the heterobilayer, with resulting electron and hole effective masses increased by more than an order of magnitude – leading to record-flat bands. These findings impose boundaries on the commonly generalized benefits of moire twistronics, while also revealing alternative feasible routes to achieve truly flat electron and hole bands to carry us to strongly correlated excitonic phenomena on demand.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001047512300001 Publication Date 2023-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited 1 Open Access Not_Open_Access: Available from 25.01.2024
Notes Approved (down) Most recent IF: 6.7; 2023 IF: 7.367
Call Number UA @ admin @ c:irua:198290 Serial 8819
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Author Kocabas, T.; Keceli, M.; Vazquez-Mayagoitia, A.; Sevik, C.
Title Gaussian approximation potentials for accurate thermal properties of two-dimensional materials Type A1 Journal article
Year 2023 Publication Nanoscale Abbreviated Journal
Volume 15 Issue 19 Pages 8772-8780
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Two-dimensional materials (2DMs) continue to attract a lot of attention, particularly for their extreme flexibility and superior thermal properties. Molecular dynamics simulations are among the most powerful methods for computing these properties, but their reliability depends on the accuracy of interatomic interactions. While first principles approaches provide the most accurate description of interatomic forces, they are computationally expensive. In contrast, classical force fields are computationally efficient, but have limited accuracy in interatomic force description. Machine learning interatomic potentials, such as Gaussian Approximation Potentials, trained on density functional theory (DFT) calculations offer a compromise by providing both accurate estimation and computational efficiency. In this work, we present a systematic procedure to develop Gaussian approximation potentials for selected 2DMs, graphene, buckled silicene, and h-XN (X = B, Al, and Ga, as binary compounds) structures. We validate our approach through calculations that require various levels of accuracy in interatomic interactions. The calculated phonon dispersion curves and lattice thermal conductivity, obtained through harmonic and anharmonic force constants (including fourth order) are in excellent agreement with DFT results. HIPHIVE calculations, in which the generated GAP potentials were used to compute higher-order force constants instead of DFT, demonstrated the first-principles level accuracy of the potentials for interatomic force description. Molecular dynamics simulations based on phonon density of states calculations, which agree closely with DFT-based calculations, also show the success of the generated potentials in high-temperature simulations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000976615200001 Publication Date 2023-04-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited Open Access Not_Open_Access
Notes Approved (down) Most recent IF: 6.7; 2023 IF: 7.367
Call Number UA @ admin @ c:irua:196722 Serial 8873
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Author Sevik, C.; Bekaert, J.; Milošević, M.V.
Title Superconductivity in functionalized niobium-carbide MXenes Type A1 Journal article
Year 2023 Publication Nanoscale Abbreviated Journal
Volume 15 Issue 19 Pages 8792-8799
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We detail the effects of Cl and S functionalization on the superconducting properties of layered (bulk) and monolayer niobium carbide (Nb2C) MXene crystals, based on first-principles calculations combined with Eliashberg theory. For bulk layered Nb2CCl2, the calculated superconducting transition temperature (T-c) is in very good agreement with the recently measured value of 6 K. We show that T-c is enhanced to 10 K for monolayer Nb2CCl2, due to an increase in the density of states at the Fermi level, and the corresponding electron-phonon coupling. We further demonstrate feasible gate- and strain-induced enhancements of T-c for both bulk-layered and monolayer Nb2CCl2 crystals, resulting in T-c values of around 38 K. In the S-functionalized Nb2CCl2 crystals, our calculations reveal the importance of phonon softening in understanding their superconducting properties. Finally, we predict that Nb3C2S2 in bulk-layered and monolayer forms is also superconducting, with a T-c of around 28 K. Considering that Nb2C is not superconducting in pristine form, our findings promote functionalization as a pathway towards robust superconductivity in MXenes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000976973900001 Publication Date 2023-04-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited Open Access OpenAccess
Notes Approved (down) Most recent IF: 6.7; 2023 IF: 7.367
Call Number UA @ admin @ c:irua:196711 Serial 8938
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Author Payne, L.M.; Albrecht, W.; Langbein, W.; Borri, P.
Title The optical nanosizer – quantitative size and shape analysis of individual nanoparticles by high-throughput widefield extinction microscopy Type A1 Journal article
Year 2020 Publication Nanoscale Abbreviated Journal Nanoscale
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanoparticles are widely utilised for a range of applications, from catalysis to medicine, requiring accurate knowledge of their size and shape. Current techniques for particle characterisation are either not very accurate or time consuming and expensive. Here we demonstrate a rapid and quantitative method for particle analysis based on measuring the polarisation-resolved optical extinction cross-section of hundreds of individual nanoparticles using wide-field microscopy, and determining the particle size and shape from the optical properties. We show measurements on three samples consisting of nominally spherical gold nanoparticles of 20 nm and 30 nm diameter, and gold nanorods of 30 nm length and 10 nm diameter. Nanoparticle sizes and shapes in three dimensions are deduced from the measured optical cross-sections at different wavelengths and light polarisation, by solving the inverse problem, using an ellipsoid model of the particle polarisability in the dipole limit. The sensitivity of the method depends on the experimental noise and the choice of wavelengths. We show an uncertainty down to about 1 nm in mean diameter, and 10% in aspect ratio when using two or three color channels, for a noise of about 50 nm<sup>2</sup>in the measured cross-section. The results are in good agreement with transmission electron microscopy, both 2D projection and tomography, of the same sample batches. Owing to its combination of experimental simplicity, ease of access to statistics over many particles, accuracy, and geometrical particle characterisation in 3D, this “optical nanosizer” method has the potential to become the technique of choice for quality control in next-generation particle manufacturing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000558928800022 Publication Date 2020-07-08
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 6.7 Times cited Open Access OpenAccess
Notes This work was supported by a Welsh Government Life Sciences Bridging Fund (grant LSBF/R6-005) and by the UK EPSRC (grant no. EP/I005072/1 and EP/M028313/1). PB acknowledges the Royal Society for her Wolfson research merit award (grant WM140077). The authors acknowledge funding from the European Commission (Grant EUSMI E191000350). WA acknowledges an Individual Fellowship from the Marie Sklodowska-Curie actions (MSCA) under the EU’s Horizon 2020 program (Grant 797153, SOPMEN), and Sara Bals for supporting the STEM measurements. The bright-field TEM was performed by Thomas Davies at Cardiff University. We acknowledge Attilio Zilli for helpful discussions and contributions in calculating the relative field strengths in the illumination and finite-element simulation of cross-sections shown in the ESI.† We acknowledge Iestyn Pope for technical support of the optical equipment. Approved (down) Most recent IF: 6.7; 2020 IF: 7.367
Call Number UA @ lucian @c:irua:170485 Serial 6397
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