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Author Sozen, Y.; Yagmurcukardes, M.; Sahin, H. doi  openurl
  Title Vibrational and optical identification of GeO₂ and GeO single layers : a first-principles study Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal (down) Phys Chem Chem Phys  
  Volume 23 Issue 37 Pages 21307-21315  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In the present work, the identification of two hexagonal phases of germanium oxides (namely GeO2 and GeO) through the vibrational and optical properties is reported using density functional theory calculations. While structural optimizations show that single-layer GeO2 and GeO crystallize in 1T and buckled phases, phonon band dispersions reveal the dynamical stability of each structure. First-order off-resonant Raman spectral predictions demonstrate that each free-standing single-layer possesses characteristic peaks that are representative for the identification of the germanium oxide phase. On the other hand, electronic band dispersion analysis shows the insulating and large-gap semiconducting nature of single-layer GeO2 and GeO, respectively. Moreover, optical absorption, reflectance, and transmittance spectra obtained by means of G(0)W(0)-BSE calculations reveal the existence of tightly bound excitons in each phase, displaying strong optical absorption. Furthermore, the excitonic gaps are found to be at deep UV and visible portions of the spectrum, for GeO2 and GeO crystals, with energies of 6.24 and 3.10 eV, respectively. In addition, at the prominent excitonic resonances, single-layers display high reflectivity with a zero transmittance, which is another indication of the strong light-matter interaction inside the crystal medium.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000697364300001 Publication Date 2021-09-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:181571 Serial 7044  
Permanent link to this record
 

 
Author Vermeyen, T.; Brence, J.; Van Echelpoel, R.; Aerts, R.; Acke, G.; Bultinck, P.; Herrebout, W. url  doi
openurl 
  Title Exploring machine learning methods for absolute configuration determination with vibrational circular dichroism Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal (down) Phys Chem Chem Phys  
  Volume 23 Issue 35 Pages 19781-19789  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Molecular Spectroscopy (MolSpec)  
  Abstract The added value of supervised Machine Learning (ML) methods to determine the Absolute Configuration (AC) of compounds from their Vibrational Circular Dichroism (VCD) spectra was explored. Among all ML methods considered, Random Forest (RF) and Feedforward Neural Network (FNN) yield the best performance for identification of the AC. At its best, FNN allows near-perfect AC determination, with accuracy of prediction up to 0.995, while RF combines good predictive accuracy (up to 0.940) with the ability to identify the spectral areas important for the identification of the AC. No loss in performance of either model is observed as long as the spectral sampling interval used does not exceed the spectral bandwidth. Increasing the sampling interval proves to be the best method to lower the dimensionality of the input data, thereby decreasing the computational cost associated with the training of the models.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000691366500001 Publication Date 2021-08-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:180290 Serial 7951  
Permanent link to this record
 

 
Author Shi, R.; Choudhuri, D.; Kashiwar, A.; Dasari, S.; Wang, Y.; Banerjee, R.; Banerjee, D. doi  openurl
  Title α phase growth and branching in titanium alloys Type A1 Journal article
  Year 2021 Publication Philosophical magazine Abbreviated Journal (down) Philos Mag  
  Volume Issue Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The morphology and spatial distribution of alpha (α) precipitates have been mapped as a function of Mo content in Ti-Mo binary alloys employing a combinatorial approach. Heat-treatments were carried out on compositionally graded Ti-xMo samples processed using a rapid throughput laser engineered net shape (LENS) process. The composition space spans 1.5 at% to 6 at% Mo with ageing at 750°C, 650°C and 600°C following a β solution treatment. Three distinct regimes of α morphology and distribution were observed. These are colony-dominated microstructures originating from grain boundary α allotriomorphs, bundles of intragranular α laths, and homogeneously distributed individual fine-scale α laths. Branching of the α precipitates was observed in all these domains in a manner reminiscent of solid-state dendritic growth. The phenomenon is particularly apparent at low volume fractions of α. Similar features are present in a wide variety of alloy compositions. 3-dimensional features of such branched structures have been analysed. Simulation of the branching process by phase field methods incorporating anisotropy in the α/β interface energy and elasticity suggests that it can be initiated at growth ledges present at broad faces of the α laths, driven by the enhancement of the diffusion flux at these steps. The dependence of branching on various parameters such as supersaturation and diffusivity, and microstructural features like ledge height and distribution and the presence of adjacent α variants has been evaluated.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000722082700001 Publication Date 2021-11-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1478-6435 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 1.505 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 1.505  
  Call Number UA @ admin @ c:irua:183616 Serial 6849  
Permanent link to this record
 

 
Author Dong, H.M.; Tao, Z.H.; Duan, Y.F.; Li, L.L.; Huang, F.; Peeters, F.M. url  doi
openurl 
  Title Substrate dependent terahertz magneto-optical properties of monolayer WS2 Type A1 Journal article
  Year 2021 Publication Optics Letters Abbreviated Journal (down) Opt Lett  
  Volume 46 Issue 19 Pages 4892-4895  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Terahertz (THz) magneto-optical (MO) properties of monolayer (ML) tungsten disulfide (WS2), placed on different substrates and subjected to external magnetic fields, are studied using THz time-domain spectroscopy (TDS). We find that the THz MO conductivity exhibits a nearly linear response in a weak magnetic field, while a distinctly nonlinear/oscillating behavior is found in strong magnetic fields owing to strong substrate-induced random impurity scattering and interactions. The THz MO response of ML WS2 depends sensitively on the choice of the substrates, which we trace back to electronic localization and the impact of the substrates on the Landau level (LL) spectrum. Our results provide an in-depth understanding of the THz MO properties of ML WS2/substrate systems, especially the effect of substrates, which can be utilized to realize atomically thin THz MO nano-devices. (C) 2021 Optical Society of America  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000702746400048 Publication Date 2021-09-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0146-9592 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 3.416 Times cited 2 Open Access OpenAccess  
  Notes Approved Most recent IF: 3.416  
  Call Number UA @ admin @ c:irua:182526 Serial 7023  
Permanent link to this record
 

 
Author Prabhakara, V.; Nuytten, T.; Bender, H.; Vandervorst, W.; Bals, S.; Verbeeck, J. pdf  url
doi  openurl
  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 (down) 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.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000708940500144 Publication Date 2021-10-11  
  Series Editor Series Title Abbreviated Series Title  
  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  
Permanent link to this record
 

 
Author Marinov, D.; de Marneffe, J.-F.; Smets, Q.; Arutchelvan, G.; Bal, K.M.; Voronina, E.; Rakhimova, T.; Mankelevich, Y.; El Kazzi, S.; Nalin Mehta, A.; Wyndaele, P.-J.; Heyne, M.H.; Zhang, J.; With, P.C.; Banerjee, S.; Neyts, E.C.; Asselberghs, I.; Lin, D.; De Gendt, S. url  doi
openurl 
  Title Reactive plasma cleaning and restoration of transition metal dichalcogenide monolayers Type A1 Journal article
  Year 2021 Publication npj 2D Materials and Applications Abbreviated Journal (down) npj 2D Mater Appl  
  Volume 5 Issue 1 Pages 17  
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The cleaning of two-dimensional (2D) materials is an essential step in the fabrication of future devices, leveraging their unique physical, optical, and chemical properties. Part of these emerging 2D materials are transition metal dichalcogenides (TMDs). So far there is limited understanding of the cleaning of “monolayer” TMD materials. In this study, we report on the use of downstream H<sub>2</sub>plasma to clean the surface of monolayer WS<sub>2</sub>grown by MOCVD. We demonstrate that high-temperature processing is essential, allowing to maximize the removal rate of polymers and to mitigate damage caused to the WS<sub>2</sub>in the form of sulfur vacancies. We show that low temperature in situ carbonyl sulfide (OCS) soak is an efficient way to resulfurize the material, besides high-temperature H<sub>2</sub>S annealing. The cleaning processes and mechanisms elucidated in this work are tested on back-gated field-effect transistors, confirming that transport properties of WS<sub>2</sub>devices can be maintained by the combination of H<sub>2</sub>plasma cleaning and OCS restoration. The low-damage plasma cleaning based on H<sub>2</sub>and OCS is very reproducible, fast (completed in a few minutes) and uses a 300 mm industrial plasma etch system qualified for standard semiconductor pilot production. This process is, therefore, expected to enable the industrial scale-up of 2D-based devices, co-integrated with silicon technology.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000613258900001 Publication Date 2021-01-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2397-7132 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Daniil Marinov has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 752164. Ekaterina Voronina, Yuri Mankelevitch, and Tatyana Rakhimova are thankful to the Russian Science Foundation (RSF) for financial support (Grant No. 16-12-10361). This study was carried out using the equipment of the shared research facilities of high-performance computing resources at Lomonosov Moscow State University and the computational resources and services of the HPC core facility CalcUA of the University of Antwerp, and VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government. Patrick With gratefully acknowledges imec’s CTO office for financial support during his stay at imec. The authors thank Mr. Surajit Sutar (imec) for his help during sample electrical characterization, and Patrick Verdonck for lab processing. Jean-François de Marneffe thank Prof. Simone Napolitano from the Free University of Brussels for useful discussions on irreversibly adsorbed polymer layers, and Cédric Huyghebaert (imec) for his continuous support in the framework of the Graphene FET Flagship core project. All authors acknowledge the support of imec’s pilot line and materials characterization and analysis (MCA) group, namely Jonathan Ludwig, Stefanie Sergeant, Thomas Nuytten, Olivier Richard, and Thierry Conard. Finally, Daniil Marinov thank Mikhail Krishtab (imec/KU Leuven) for his help in selecting the optimal plasma etch system for this work. Part of this project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 649953. Approved Most recent IF: NA  
  Call Number PLASMANT @ plasmant @c:irua:175871 Serial 6671  
Permanent link to this record
 

 
Author Chen, X.; Li, L.; Peeters, F.M.; Sanyal, B. url  doi
openurl 
  Title Two-dimensional oxygen functionalized honeycomb and zigzag dumbbell silicene with robust Dirac cones Type A1 Journal article
  Year 2021 Publication New Journal Of Physics Abbreviated Journal (down) New J Phys  
  Volume 23 Issue 2 Pages 023007  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Dumbbell-like structures are recently found to be energetically favored in group IV two-dimensional (2D) materials, exhibiting rich physics and many interesting properties. In this paper, using first-principles calculations, we have investigated the oxidized form of the hexagonal honeycomb (ODB-h) and zigzag dumbbell silicene (ODB-z). We confirm that both oxidization processes are energetically favorable, and their phonon spectra further demonstrate the dynamic stability. Contrary to the pristine dumbbell silicene structures (PDB-h and PDB-z silicene), these oxidized products ODB-h and ODB-z silicene are both semimetals with Dirac cones at the Fermi level. The Dirac cones of ODB-h and ODB-z silicene are at the K point and between Y and Gamma points respectively, possessing high Fermi velocities of 3.1 x 10(5) m s(-1) (ODB-h) and 2.9-3.4 x 10(5) m s(-1) (ODB-z). The origin of the Dirac cones is further explained by tight-binding models. The semimetallic properties of ODB-h and ODB-z are sensitive to compression due to the self-absorption effect, but quite robust against the tensile strain. These outstanding properties make oxidized dumbbell silicene a promising material for quantum computing and high-speed electronic devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000616114900001 Publication Date 2021-01-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 2 Open Access OpenAccess  
  Notes Approved Most recent IF: 3.786  
  Call Number UA @ admin @ c:irua:176575 Serial 6741  
Permanent link to this record
 

 
Author Chen, Q.; Guo, A.-M.; Liu, J.; Peeters, F.M.; Sun, Q.-F. url  doi
openurl 
  Title Topological phase transitions and Majorana zero modes in DNA double helix coupled to s-wave superconductors Type A1 Journal article
  Year 2021 Publication New Journal Of Physics Abbreviated Journal (down) New J Phys  
  Volume 23 Issue 9 Pages 093047  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Topological properties of a double-stranded DNA (dsDNA) proximity-coupled by an s-wave superconductor are investigated, in which the energy spectra and the differential conductance are calculated within the framework of tight-binding approximation. Our results indicate that this dsDNA-superconductor system hosts Majorana zero modes (MZMs) when the Zeeman field is perpendicular to the helix axis, whereas no MZM could be observed when the Zeeman field is parallel to the helix axis, in sharp contrast to previous studies on nanowires including single-stranded DNA. In particular, two topological phase transitions could take place in the dsDNA-superconductor system by changing the Zeeman field, one from a topological trivial phase to a topological nontrivial phase with one pair of MZMs in small Zeeman field regime, and the other from a phase with one pair of MZMs to a phase with two pairs of MZMs by further increasing the Zeeman field. In the presence of a gate field normal to the helix axis, the topological nontrivial phase with two pairs of MZMs can transform into the phase with one pair of MZMs. The topological phase with one pair of MZMs is more stable and robust against Anderson disorder.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000702122000001 Publication Date 2021-09-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 7 Open Access OpenAccess  
  Notes Approved Most recent IF: 3.786  
  Call Number UA @ admin @ c:irua:182597 Serial 7033  
Permanent link to this record
 

 
Author Bafekry, A.; Faraji, M.; Ziabari, A.A.; Fadlallah, M.M.; Nguyen, C., V; Ghergherehchi, M.; Feghhi, S.A.H. url  doi
openurl 
  Title A van der Waals heterostructure of MoS₂/MoSi₂N₄ : a first-principles study Type A1 Journal article
  Year 2021 Publication New Journal Of Chemistry Abbreviated Journal (down) New J Chem  
  Volume 45 Issue 18 Pages 8291-8296  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the successful preparation of MoSi2N4 monolayers in the last year [Y.-L. Hong et al., Science, 2020, 369, 670-674], we investigate the structural, electronic and optical properties of the MoS2/MoSi2N4 heterostructure (HTS). The phonon dispersion and the binding energy calculations refer to the stability of the HTS. The heterostructure has an indirect bandgap of 1.26 (1.84) eV using PBE (HSE06) which is smaller than the corresponding value of MoSi2N4 and MoS2 monolayers. We find that the work function of the MoS2/MoSi2N4 HTS is smaller than the corresponding value of its individual monolayers. The heterostructure structure can enhance the absorption of light spectra not only in the ultraviolet region but also in the visible region as compared to MoSi2N4 and MoS2 monolayers. The refractive index behaviour of the HTS can be described as the cumulative effect which is well described in terms of a combination of the individual effects (the refractive index of MoSi2N4 and MoS2 monolayers).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000642436200001 Publication Date 2021-03-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.269 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.269  
  Call Number UA @ admin @ c:irua:178300 Serial 6964  
Permanent link to this record
 

 
Author Faraji, M.; Bafekry, A.; Gogova, D.; Hoat, D.M.; Ghergherehchi, M.; Chuong, N.V.; Feghhi, S.A.H. url  doi
openurl 
  Title Novel two-dimensional ZnO₂, CdO₂ and HgO₂ monolayers: a first-principles-based prediction Type A1 Journal article
  Year 2021 Publication New Journal Of Chemistry Abbreviated Journal (down) New J Chem  
  Volume 45 Issue Pages 9368-9374  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this paper, the existence of monolayers with the chemical formula XO2, where X = Zn, Cd, and Hg with hexagonal and tetragonal lattice structures is theoretically predicted by means of first principles calculations. Through cohesive energy calculation and phonon dispersion simulation, it has been proven that the two-dimensional XO2 monolayers proposed are energetically and dynamically stable suggesting their potential experimental realization. Our detailed study demonstrates that these novel newly predicted materials are half-metals and dilute magnetic semiconductors, and they exhibit magnetism in the ground state. The half-metallic character could find many applications in electronic and spintronic devices. Research into the magnetic properties revealed here can enrich theoretical knowledge in this area and provide more potential candidates for XO2 2D-based materials and van der Waals heterostructures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000645671700001 Publication Date 2021-04-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.269 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.269  
  Call Number UA @ admin @ c:irua:178245 Serial 7006  
Permanent link to this record
 

 
Author Dubinina, T.; Maklakov, S.; Petrusevich, E.; Borisova, N.E.; Trashin, S.A.; De Wael, K.; Tomilova, L.G. url  doi
openurl 
  Title Photoactive layers for photovoltaics based on near-infrared absorbing aryl-substituted naphthalocyanine complexes : preparation and investigation of properties Type A1 Journal article
  Year 2021 Publication New Journal Of Chemistry Abbreviated Journal (down) New J Chem  
  Volume 45 Issue 32 Pages 14815-14821  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Photoactive layers based on aryl- and aryloxy-substituted naphthalocyanines and conductive polymer poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) were prepared using the spin-coating technique and their conductivity was tested in dark and under illumination. For this purpose novel octa-2-naphthoxy-substituted naphthalocyanines were synthesized starting from 6,7-di(2-naphthoxy)naphthalene-2,3-dicarbonitrile. For those novel naphthalocyanine complexes, spectral and electrochemical data were measured and compared with corresponding ones for other aryl-substituted analogues. In comparison to the previously studied naphthalocyanines with alkyl- and phenyl- groups, the formal oxidation and reduction potentials were rather similar. All target complexes demonstrate intense near-infrared absorption at 760-790 nm, which is about 30 nm bathochromically shifted in thin films. The photo-resistive effect was found increasing from composites comprised of naphthoxy- to phenyl-substituted naphthalocyanines. This peculiarity was explained by using optical and atomic force microscopy in terms of different sizes of aggregates formed. The photo-response time for novel composited was approximately 3 s, which is about 20 times faster than measured previously for the films deposited via the drop-casting technique.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000680389800001 Publication Date 2021-07-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 3.269 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.269  
  Call Number UA @ admin @ c:irua:179884 Serial 8379  
Permanent link to this record
 

 
Author Samae, V.; Cordier, P.; Demouchy, S.; Bollinger, C.; Gasc, J.; Koizumi, S.; Mussi, A.; Schryvers, D.; Idrissi, H. pdf  url
doi  openurl
  Title Stress-induced amorphization triggers deformation in the lithospheric mantle Type A1 Journal article
  Year 2021 Publication Nature Abbreviated Journal (down) Nature  
  Volume 591 Issue 7848 Pages 82-86  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The mechanical properties of olivine-rich rocks are key to determining the mechanical coupling between Earth's lithosphere and asthenosphere. In crystalline materials, the motion of crystal defects is fundamental to plastic flow(1-4.) However, because the main constituent of olivine-rich rocks does not have enough slip systems, additional deformation mechanisms are needed to satisfy strain conditions. Experimental studies have suggested a non-Newtonian, grain-size-sensitive mechanism in olivine involving grain-boundary sliding(5,6). However, very few microstructural investigations have been conducted on grain-boundary sliding, and there is no consensus on whether a single or multiple physical mechanisms are at play. Most importantly, there are no theoretical frameworks for incorporating the mechanics of grain boundaries in polycrystalline plasticity models. Here we identify a mechanism for deformation at grain boundaries in olivine-rich rocks. We show that, in forsterite, amorphization takes place at grain boundaries under stress and that the onset of ductility of olivine-rich rocks is due to the activation of grain-boundary mobility in these amorphous layers. This mechanism could trigger plastic processes in the deep Earth, where high-stress conditions are encountered (for example, at the brittle-plastic transition). Our proposed mechanism is especially relevant at the lithosphere-asthenosphere boundary, where olivine reaches the glass transition temperature, triggering a decrease in its viscosity and thus promoting grain-boundary sliding.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000626921700014 Publication Date 2021-03-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 40.137 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 40.137  
  Call Number UA @ admin @ c:irua:176656 Serial 6738  
Permanent link to this record
 

 
Author Wang, L.; Li, Y.; Yang, X.-Y.; Zhang, B.-B.; Ninane, N.; Busscher, H.J.; Hu, Z.-Y.; Delneuville, C.; Jiang, N.; Xie, H.; Van Tendeloo, G.; Hasan, T.; Su, B.-L. url  doi
openurl 
  Title Single-cell yolk-shell nanoencapsulation for long-term viability with size-dependent permeability and molecular recognition Type A1 Journal article
  Year 2021 Publication National Science Review Abbreviated Journal (down) Natl Sci Rev  
  Volume 8 Issue 4 Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Like nanomaterials, bacteria have been unknowingly used for centuries. They hold significant economic potential for fuel and medicinal compound production. Their full exploitation, however, is impeded by low biological activity and stability in industrial reactors. Though cellular encapsulation addresses these limitations, cell survival is usually compromised due to shell-to-cell contacts and low permeability. Here, we report ordered packing of silica nanocolloids with organized, uniform and tunable nanoporosities for single cyanobacterium nanoencapsulation using protamine as an electrostatic template. A space between the capsule shell and the cell is created by controlled internalization of protamine, resulting in a highly ordered porous shell-void-cell structure formation. These unique yolk-shell nano structures provide long-term cell viability with superior photosynthetic activities and resistance in harsh environments. In addition, engineering the colloidal packing allows tunable shell-pore diameter for size-dependent permeability and introduction of new functionalities for specific molecular recognition. Our strategy could significantly enhance the activity and stability of cyanobacteria for various nanobiotechnological applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000651827200002 Publication Date 2020-05-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2095-5138 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.843 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 8.843  
  Call Number UA @ admin @ c:irua:179085 Serial 6885  
Permanent link to this record
 

 
Author Zou, Y.-C.; Mogg, L.; Clark, N.; Bacaksiz, C.; Milanovic, S.; Sreepal, V.; Hao, G.-P.; Wang, Y.-C.; Hopkinson, D.G.; Gorbachev, R.; Shaw, S.; Novoselov, K.S.; Raveendran-Nair, R.; Peeters, F.M.; Lozada-Hidalgo, M.; Haigh, S.J. url  doi
openurl 
  Title Ion exchange in atomically thin clays and micas Type A1 Journal article
  Year 2021 Publication Nature Materials Abbreviated Journal (down) Nat Mater  
  Volume 20 Issue 12 Pages 1677-1682  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The physical properties of clays and micas can be controlled by exchanging ions in the crystal lattice. Atomically thin materials can have superior properties in a range of membrane applications, yet the ion-exchange process itself remains largely unexplored in few-layer crystals. Here we use atomic-resolution scanning transmission electron microscopy to study the dynamics of ion exchange and reveal individual ion binding sites in atomically thin and artificially restacked clays and micas. We find that the ion diffusion coefficient for the interlayer space of atomically thin samples is up to 10(4) times larger than in bulk crystals and approaches its value in free water. Samples where no bulk exchange is expected display fast exchange at restacked interfaces, where the exchanged ions arrange in islands with dimensions controlled by the moire superlattice dimensions. We attribute the fast ion diffusion to enhanced interlayer expandability resulting from weaker interlayer binding forces in both atomically thin and restacked materials. This work provides atomic scale insights into ion diffusion in highly confined spaces and suggests strategies to design exfoliated clay membranes with enhanced performance. Layered clays are of interest for membranes and many other applications but their ion-exchange dynamics remain unexplored in atomically thin materials. Here, using electron microscopy, it is found that the ion diffusion for few-layer two-dimensional clays approaches that of free water and that superlattice cation islands can form in twisted and restacked materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000689664000001 Publication Date 2021-09-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1476-1122; 1476-4660 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 39.737 Times cited 2 Open Access OpenAccess  
  Notes Approved Most recent IF: 39.737  
  Call Number UA @ admin @ c:irua:181691 Serial 6999  
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Author Zheng, Y.-R.; Vernieres, J.; Wang, Z.; Zhang, K.; Hochfilzer, D.; Krempl, K.; Liao, T.-W.; Presel, F.; Altantzis, T.; Fatermans, J.; Scott, S.B.; Secher, N.M.; Moon, C.; Liu, P.; Bals, S.; Van Aert, S.; Cao, A.; Anand, M.; Nørskov, J.K.; Kibsgaard, J.; Chorkendorff, I. url  doi
openurl 
  Title Monitoring oxygen production on mass-selected iridium–tantalum oxide electrocatalysts Type A1 Journal article
  Year 2021 Publication Nature Energy Abbreviated Journal (down) Nat Energy  
  Volume Issue Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)  
  Abstract Development of low-cost and high-performance oxygen evolution reaction catalysts is key to implementing polymer electrolyte membrane water electrolyzers for hydrogen production. Iridium-based oxides are the state-of-the-art acidic oxygen evolution reactio catalysts but still suffer from inadequate activity and stability, and iridium's scarcity motivates the discovery of catalysts with lower iridium loadings. Here we report a mass-selected iridium-tantalum oxide catalyst prepared by a magnetron-based cluster source with considerably reduced noble-metal loadings beyond a commercial IrO2 catalyst. A sensitive electrochemistry/mass-spectrometry instrument coupled with isotope labelling was employed to investigate the oxygen production rate under dynamic operating conditions to account for the occurrence of side reactions and quantify the number of surface active sites. Iridium-tantalum oxide nanoparticles smaller than 2 nm exhibit a mass activity of 1.2 ± 0.5 kA “g” _“Ir” ^“-1” and a turnover frequency of 2.3 ± 0.9 s-1 at 320 mV overpotential, which are two and four times higher than those of mass-selected IrO2, respectively. Density functional theory calculations reveal that special iridium coordinations and the lowered aqueous decomposition free energy might be responsible for the enhanced performance.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000728458000001 Publication Date 2021-12-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2058-7546 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 95 Open Access OpenAccess  
  Notes Y.-R.Z. and Z.W acknowledge funding from the Toyota Research Institute. This project has received funding from VILLUM FONDEN (grant no. 9455) and the European Research Council under the European Union’s Horizon 2020 research and innovation programme (grants no. 741860-CLUNATRA, no. 815128−REALNANO and no. 770887−PICOMETRICS). S.B. and S.V.A. acknowledge funding from the Research Foundation Flanders (FWO, G026718N and G050218N). T.A. acknowledges the University of Antwerp Research Fund (BOF). STEM measurements were supported by the European Union's Horizon 2020 Research Infrastructure-Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3.; sygmaSB Approved Most recent IF: NA  
  Call Number EMAT @ emat @c:irua:184794 Serial 6903  
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Author Samaee, V.; Dupraz, M.; Pardoen, T.; VAn Swygenhoven, H.; Schryvers, D.; Idrissi, H. url  doi
openurl 
  Title Deciphering the interactions between single arm dislocation sources and coherent twin boundary in nickel bi-crystal Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) Nat Commun  
  Volume 12 Issue 1 Pages 962  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The introduction of a well-controlled population of coherent twin boundaries (CTBs) is an attractive route to improve the strength ductility product in face centered cubic (FCC) metals. However, the elementary mechanisms controlling the interaction between single arm dislocation sources (SASs), often present in nanotwinned FCC metals, and CTB are still not well understood. Here, quantitative in-situ transmission electron microscopy (TEM) observations of these mechanisms under tensile loading are performed on submicron Ni bi-crystal. We report that the absorption of curved screw dislocations at the CTB leads to the formation of constriction nodes connecting pairs of twinning dislocations at the CTB plane in agreement with large scale 3D atomistic simulations. The coordinated motion of the twinning dislocation pairs due to the presence of the nodes leads to a unique CTB sliding mechanism, which plays an important role in initiating the fracture process at a CTB ledge. TEM observations of the interactions between non-screw dislocations and the CTB highlight the importance of the synergy between the repulsive force of the CTB and the back stress from SASs when the interactions occur in small volumes. Interactions of dislocations with coherent twin boundaries contribute to strength and ductility in metals, but investigating the interaction mechanisms is challenging. Here the authors unravel these mechanisms through quantitative in-situ transmission electron microscopy observations in nickel bi-crystal samples under tensile loading.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000620142700024 Publication Date 2021-02-11  
  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 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:176680 Serial 6722  
Permanent link to this record
 

 
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. url  doi
openurl 
  Title Efficient long-range conduction in cable bacteria through nickel protein wires Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) 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.  
  Address  
  Corporate Author Thesis  
  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 Wang, D.; van der Wee, E.B.; Zanaga, D.; Altantzis, T.; Wu, Y.; Dasgupta, T.; Dijkstra, M.; Murray, C.B.; Bals, S.; van Blaaderen, A. url  doi
openurl 
  Title Quantitative 3D real-space analysis of Laves phase supraparticles Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) Nat Commun  
  Volume 12 Issue 1 Pages 3980  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)  
  Abstract 3D real-space analysis of thick nanoparticle crystals is non-trivial. Here, the authors demonstrate the structural analysis of a bulk-like Laves phase by imaging an off-stoichiometric binary mixture of hard-sphere-like nanoparticles in spherical confinement by electron tomography, enabling defect analysis on the single-particle level. Assembling binary mixtures of nanoparticles into crystals, gives rise to collective properties depending on the crystal structure and the individual properties of both species. However, quantitative 3D real-space analysis of binary colloidal crystals with a thickness of more than 10 layers of particles has rarely been performed. Here we demonstrate that an excess of one species in the binary nanoparticle mixture suppresses the formation of icosahedral order in the self-assembly in droplets, allowing the study of bulk-like binary crystal structures with a spherical morphology also called supraparticles. As example of the approach, we show single-particle level analysis of over 50 layers of Laves phase binary crystals of hard-sphere-like nanoparticles using electron tomography. We observe a crystalline lattice composed of a random mixture of the Laves phases. The number ratio of the binary species in the crystal lattice matches that of a perfect Laves crystal. Our methodology can be applied to study the structure of a broad range of binary crystals, giving insights into the structure formation mechanisms and structure-property relations of nanomaterials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000687320200032 Publication Date 2021-06-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 10 Open Access OpenAccess  
  Notes M. Hermes is sincerely thanked for providing interactive views of the structures in this work. The authors thank I. Lobato, S. Dussi, L. Filion, E. Boattini, S. Paliwal, B. van der Meer and X. Xie for fruitful discussions. D.W., E.B.v.d.W. and A.v.B. acknowledge partial financial support from the European Research Council under the European Union’s Seventh Framework Program (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. T.D. and M.D. acknowledge financial support from the Industrial Partnership Program, “Computational Sciences for Energy Research” (Grant no. 13CSER025), of the Netherlands Organization for Scientific Research (NWO), which was co-financed by Shell Global Solutions International B.V. S.B. acknowledges financial support from ERC Consolidator Grant No. 815128 REALNANO. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). C.B.M and Y.W. acknowledge support for materials synthesis from the Office of Naval Research Multidisciplinary University Research Initiative Award ONR N00014-18-1-2497. The authors acknowledge EM Square center at Utrecht University for the access to the microscopes.; sygmaSB Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:181662 Serial 6845  
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Author Zalalutdinov, M.K.; Robinson, J.T.; Fonseca, J.J.; LaGasse, S.W.; Pandey, T.; Lindsay, L.R.; Reinecke, T.L.; Photiadis, D.M.; Culbertson, J.C.; Cress, C.D.; Houston, B.H. url  doi
openurl 
  Title Acoustic cavities in 2D heterostructures Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) Nat Commun  
  Volume 12 Issue 1 Pages 3267  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional (2D) materials offer unique opportunities in engineering the ultrafast spatiotemporal response of composite nanomechanical structures. In this work, we report on high frequency, high quality factor (Q) 2D acoustic cavities operating in the 50-600GHz frequency (f) range with f x Q up to 1 x 10(14). Monolayer steps and material interfaces expand cavity functionality, as demonstrated by building adjacent cavities that are isolated or strongly-coupled, as well as a frequency comb generator in MoS2/h-BN systems. Energy dissipation measurements in 2D cavities are compared with attenuation derived from phonon-phonon scattering rates calculated using a fully microscopic ab initio approach. Phonon lifetime calculations extended to low frequencies (<1THz) and combined with sound propagation analysis in ultrathin plates provide a framework for designing acoustic cavities that approach their fundamental performance limit. These results provide a pathway for developing platforms employing phonon-based signal processing and for exploring the quantum nature of phonons. Here, authors report on acoustic cavities in 2D materials operating in the 50-600GHz range and show that quality factors approach the limit set by lattice anharmonicity. Functionality expanded by heterogeneities (steps and interfaces) is demonstrated through coupled cavities and frequency comb generation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000660772400004 Publication Date 2021-06-01  
  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 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:179597 Serial 6968  
Permanent link to this record
 

 
Author Sun, P.Z.; Yagmurcukardes, M.; Zhang, R.; Kuang, W.J.; Lozada-Hidalgo, M.; Liu, B.L.; Cheng, H.-M.; Wang, F.C.; Peeters, F.M.; Grigorieva, I.V.; Geim, A.K. url  doi
openurl 
  Title Exponentially selective molecular sieving through angstrom pores Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) Nat Commun  
  Volume 12 Issue 1 Pages 7170  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional crystals with angstrom-scale pores are widely considered as candidates for a next generation of molecular separation technologies aiming to provide extreme, exponentially large selectivity combined with high flow rates. No such pores have been demonstrated experimentally. Here we study gas transport through individual graphene pores created by low intensity exposure to low kV electrons. Helium and hydrogen permeate easily through these pores whereas larger species such as xenon and methane are practically blocked. Permeating gases experience activation barriers that increase quadratically with molecules' kinetic diameter, and the effective diameter of the created pores is estimated as similar to 2 angstroms, about one missing carbon ring. Our work reveals stringent conditions for achieving the long sought-after exponential selectivity using porous two-dimensional membranes and suggests limits on their possible performance. Two-dimensional membranes with angstrom-sized pores are predicted to combine high permeability with exceptional selectivity, but experimental demonstration has been challenging. Here the authors realize angstrom-sized pores in monolayer graphene and demonstrate gas transport with activation barriers increasing quadratically with the molecular kinetic diameter.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000728562700016 Publication Date 2021-12-09  
  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 28 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:184840 Serial 6989  
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Author Lyu, Y.-Y.; Jiang, J.; Wang, Y.-L.; Xiao, Z.-L.; Dong, S.; Chen, Q.-H.; Milošević, M.V.; Wang, H.; Divan, R.; Pearson, J.E.; Wu, P.; Peeters, F.M.; Kwok, W.-K. url  doi
openurl 
  Title Superconducting diode effect via conformal-mapped nanoholes Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) Nat Commun  
  Volume 12 Issue 1 Pages 2703  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract A superconducting diode is an electronic device that conducts supercurrent and exhibits zero resistance primarily for one direction of applied current. Such a dissipationless diode is a desirable unit for constructing electronic circuits with ultralow power consumption. However, realizing a superconducting diode is fundamentally and technologically challenging, as it usually requires a material structure without a centre of inversion, which is scarce among superconducting materials. Here, we demonstrate a superconducting diode achieved in a conventional superconducting film patterned with a conformal array of nanoscale holes, which breaks the spatial inversion symmetry. We showcase the superconducting diode effect through switchable and reversible rectification signals, which can be three orders of magnitude larger than that from a flux-quantum diode. The introduction of conformal potential landscapes for creating a superconducting diode is thereby proven as a convenient, tunable, yet vastly advantageous tool for superconducting electronics. This could be readily applicable to any superconducting materials, including cuprates and iron-based superconductors that have higher transition temperatures and are desirable in device applications. A superconducting diode is dissipationless and desirable for electronic circuits with ultralow power consumption, yet it remains challenging to realize it. Here, the authors achieve a superconducting diode in a conventional superconducting film patterned with a conformal array of nanoscale holes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000658724200018 Publication Date 2021-05-11  
  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 71 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:179611 Serial 7024  
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Author Lee, Y.; Forte, J.D.'arf S.; Chaves, A.; Kumar, A.; Tran, T.T.; Kim, Y.; Roy, S.; Taniguchi, T.; Watanabe, K.; Chernikov, A.; Jang, J.I.; Low, T.; Kim, J. url  doi
openurl 
  Title Boosting quantum yields in two-dimensional semiconductors via proximal metal plates Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) Nat Commun  
  Volume 12 Issue 1 Pages 7095  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The short exciton lifetime and strong exciton-exciton interaction in transition metal dichalcogenides limit the efficiency of exciton emission. Here, the authors show that exciton-exciton interaction in monolayer WS2 can be screened using proximal metal plates, leading to an improved quantum yield. Monolayer transition metal dichalcogenides (1L-TMDs) have tremendous potential as atomically thin, direct bandgap semiconductors that can be used as convenient building blocks for quantum photonic devices. However, the short exciton lifetime due to the defect traps and the strong exciton-exciton interaction in TMDs has significantly limited the efficiency of exciton emission from this class of materials. Here, we show that exciton-exciton interaction in 1L-WS2 can be effectively screened using an ultra-flat Au film substrate separated by multilayers of hexagonal boron nitride. Under this geometry, induced dipolar exciton-exciton interaction becomes quadrupole-quadrupole interaction because of effective image dipoles formed within the metal. The suppressed exciton-exciton interaction leads to a significantly improved quantum yield by an order of magnitude, which is also accompanied by a reduction in the exciton-exciton annihilation (EEA) rate, as confirmed by time-resolved optical measurements. A theoretical model accounting for the screening of the dipole-dipole interaction is in a good agreement with the dependence of EEA on exciton densities. Our results suggest that fundamental EEA processes in the TMD can be engineered through proximal metallic screening, which represents a practical approach towards high-efficiency 2D light emitters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000728559600014 Publication Date 2021-12-07  
  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 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:184870 Serial 7566  
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Author Wang, F.; Wang, C.; Chaves, A.; Song, C.; Zhang, G.; Huang, S.; Lei, Y.; Xing, Q.; Mu, L.; Xie, Y.; Yan, H. doi  openurl
  Title Prediction of hyperbolic exciton-polaritons in monolayer black phosphorus Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal (down) Nat Commun  
  Volume 12 Issue 1 Pages 5628  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Hyperbolic polaritons exhibit large photonic density of states and can be collimated in certain propagation directions. The majority of hyperbolic polaritons are sustained in man-made metamaterials. However, natural-occurring hyperbolic materials also exist. Particularly, natural in-plane hyperbolic polaritons in layered materials have been demonstrated in MoO3 and WTe2, which are based on phonon and plasmon resonances respectively. Here, by determining the anisotropic optical conductivity (dielectric function) through optical spectroscopy, we predict that monolayer black phosphorus naturally hosts hyperbolic exciton-polaritons due to the pronounced in-plane anisotropy and strong exciton resonances. We simultaneously observe a strong and sharp ground state exciton peak and weaker excited states in high quality monolayer samples in the reflection spectrum, which enables us to determine the exciton binding energy of similar to 452 meV. Our work provides another appealing platform for the in-plane natural hyperbolic polaritons, which is based on excitons rather than phonons or plasmons.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000698984500003 Publication Date 2021-10-12  
  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 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:191688 Serial 8404  
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Author Bafekry, A.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Shojaei, F.; Feghhi, S.A.H.; Ghergherehchi, M.; Gogova, D. pdf  url
doi  openurl
  Title Two-dimensional carbon nitride C₆N nanosheet with egg-comb-like structure and electronic properties of a semimetal Type A1 Journal article
  Year 2021 Publication Nanotechnology Abbreviated Journal (down) Nanotechnology  
  Volume 32 Issue 21 Pages 215702  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract In this study, the structural, electronic and optical properties of theoretically predicted C6N monolayer structure are investigated by means of Density Functional Theory-based First-Principles Calculations. Phonon band dispersion calculations and molecular dynamics simulations reveal the dynamical and thermal stability of the C6N single-layer structure. We found out that the C6N monolayer has large negative in-plane Poisson's ratios along both X and Y direction and the both values are almost four times that of the famous-pentagraphene. The electronic structure shows that C6N monolayer is a semi-metal and has a Dirac-point in the BZ. The optical analysis using the random phase approximation method constructed over HSE06 illustrates that the first peak of absorption coefficient of the C6N monolayer along all polarizations is located in the IR range of spectrum, while the second absorption peak occurs in the visible range, which suggests its potential applications in optical and electronic devices. Interestingly, optically anisotropic character of this system is highly desirable for the design of polarization-sensitive photodetectors. Thermoelectric properties such as Seebeck coefficient, electrical conductivity, electronic thermal conductivity and power factor are investigated as a function of carrier doping at temperatures 300, 400, and 500 K. In general, we predict that the C6N monolayer could be a new platform for study of novel physical properties in two-dimensional semi-metal materials, which may provide new opportunities to realize high-speed low-dissipation devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000624531500001 Publication Date 2020-12-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.44 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.44  
  Call Number UA @ admin @ c:irua:176648 Serial 6740  
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Author Osca, J.; Moors, K.; Sorée, B.; Serra, L. pdf  doi
openurl 
  Title Fabry-Perot interferometry with gate-tunable 3D topological insulator nanowires Type A1 Journal article
  Year 2021 Publication Nanotechnology Abbreviated Journal (down) Nanotechnology  
  Volume 32 Issue 43 Pages 435002  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Three-dimensional topological insulator (3D TI) nanowires display remarkable magnetotransport properties that can be attributed to their spin-momentum-locked surface states such as quasiballistic transport and Aharonov-Bohm oscillations. Here, we focus on the transport properties of a 3D TI nanowire with a gated section that forms an electronic Fabry-Perot (FP) interferometer that can be tuned to act as a surface-state filter or energy barrier. By tuning the carrier density and length of the gated section of the wire, the interference pattern can be controlled and the nanowire can become fully transparent for certain topological surface-state input modes while completely filtering out others. We also consider the interplay of FP interference with an external magnetic field, with which Klein tunneling can be induced, and transverse asymmetry of the gated section, e.g. due to a top-gated structure, which displays an interesting analogy with Rashba nanowires. Due to its rich conductance phenomenology, we propose a 3D TI nanowire with gated section as an ideal setup for a detailed transport-based characterization of 3D TI nanowire surface states near the Dirac point, which could be useful towards realizing 3D TI nanowire-based topological superconductivity and Majorana bound states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000682173800001 Publication Date 2021-07-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.44 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.44  
  Call Number UA @ admin @ c:irua:180487 Serial 6990  
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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. pdf  url
doi  openurl
  Title Three-dimensional atomic structure of supported Au nanoparticles at high temperature Type A1 Journal article
  Year 2021 Publication Nanoscale Abbreviated Journal (down) 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 Most recent IF: 7.367  
  Call Number EMAT @ emat @c:irua:174858 Serial 6665  
Permanent link to this record
 

 
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. url  doi
openurl 
  Title Spherical core–shell alumina support particles for model platinum catalysts Type A1 Journal article
  Year 2021 Publication Nanoscale Abbreviated Journal (down) 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 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. doi  openurl
  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 (down) 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 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. url  doi
openurl 
  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 (down) 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 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. pdf  url
doi  openurl
  Title Deep learning-based denoising for improved dose efficiency in EDX tomography of nanoparticles Type A1 Journal article
  Year 2021 Publication Nanoscale Abbreviated Journal (down) 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 Most recent IF: 7.367  
  Call Number EMAT @ emat @c:irua:179756 Serial 6799  
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