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Author Bourgeois, L.; Zhang, Y.; Zhang, Z.; Chen, Y.; Medhekar, N., V url  doi
openurl 
  Title Transforming solid-state precipitates via excess vacancies Type A1 Journal article
  Year 2020 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 11 Issue 1 Pages 1248  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Many phase transformations associated with solid-state precipitation look structurally simple, yet, inexplicably, take place with great difficulty. A classic case of difficult phase transformations is the nucleation of strengthening precipitates in high-strength lightweight aluminium alloys. Here, using a combination of atomic-scale imaging, simulations and classical nucleation theory calculations, we investigate the nucleation of the strengthening phase theta' onto a template structure in the aluminium-copper alloy system. We show that this transformation can be promoted in samples exhibiting at least one nanoscale dimension, with extremely high nucleation rates for the strengthening phase as well as for an unexpected phase. This template-directed solid-state nucleation pathway is enabled by the large influx of surface vacancies that results from heating a nanoscale solid. Template-directed nucleation is replicated in a bulk alloy as well as under electron irradiation, implying that this difficult transformation can be facilitated under the general condition of sustained excess vacancy concentrations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000549162600025 Publication Date 2020-03-06  
  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 16.6 Times cited 5 Open Access OpenAccess  
  Notes ; The authors are indebted to Matthew Weyland for his expert advice on aberrationcorrected scanning transmission electron microscopy. L.B. would like to acknowledge initial discussions with B.C. Muddle and J.F. Nie many years ago regarding the possible thermodynamic role of vacancies in solid-state precipitation. The authors acknowledge funding from the Australian Research Council (LE0454166, LE110100223), the Victorian State Government and Monash University for instrumentation, and use of the facilities within the Monash Centre for Electron Microscopy. The authors thank Flame Burgmann, Dougal McCulloch and Edwin Mayes for access to and assistance at the Microscopy and Microanalysis Facility at RMIT University. L.B. and N.M. acknowledge the financial support of the Australian Research Council (DP150100558). Authors also gratefully acknowledge the computational support from MonARCH, MASSIVE and the National Computing Infrastructure and Pawsey Supercomputing Centre. ZZ and YZ are thankful to Monash University for a Monash Graduate Scholarship, a Monash International Postgraduate Research Scholarship. Z.Z. is grateful for a Monash Centre for Electron Microscopy Postgraduate Scholarship. The authors are grateful to Anita Hill for advice. ; Approved Most recent IF: 16.6; 2020 IF: 12.124  
  Call Number UA @ admin @ c:irua:170797 Serial 6635  
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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 Nat Commun  
  Volume 12 Issue 1 Pages 962  
  Keywords (down) 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  
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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 Nature  
  Volume 591 Issue 7848 Pages 82-86  
  Keywords (down) 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.  
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  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  
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Author Boschker, H.T.S.; Cook, P.L.M.; Polerecky, L.; Eachambadi, R.T.; Lozano, H.; Hidalgo-Martinez, S.; Khalenkow, D.; Spampinato, V.; Claes, N.; Kundu, P.; Wang, D.; Bals, S.; Sand, K.K.; Cavezza, F.; Hauffman, T.; Bjerg, J.T.; Skirtach, A.G.; Kochan, K.; McKee, M.; Wood, B.; Bedolla, D.; Gianoncelli, A.; Geerlings, N.M.J.; Van Gerven, N.; Remaut, H.; Geelhoed, J.S.; Millan-Solsona, R.; Fumagalli, L.; Nielsen, L.P.; Franquet, A.; Manca, J.V.; Gomila, G.; Meysman, F.J.R. 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 Nat Commun  
  Volume 12 Issue 1 Pages 3996  
  Keywords (down) 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 Haug, C.; Ruebeling, F.; Kashiwar, A.; Gumbsch, P.; Kübel, C.; Greiner, C. doi  openurl
  Title Early deformation mechanisms in the shear affected region underneath a copper sliding contact Type A1 Journal article
  Year 2020 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 11 Issue 1 Pages 839-8  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Dislocation mediated plastic deformation decisively influences the friction coefficient and the microstructural changes at many metal sliding interfaces during tribological loading. This work explores the initiation of a tribologically induced microstructure in the vicinity of a copper twin boundary. Two distinct horizontal dislocation traces lines (DTL) are observed in their interaction with the twin boundary beneath the sliding interface. DTL formation seems unaffected by the presence of the twin boundary but the twin boundary acts as an indicator of the occurring deformation mechanisms. Three concurrent elementary processes can be identified: simple shear of the subsurface area in sliding direction, localized shear at the primary DTL and crystal rotation in the layers above and between the DTLs around axes parallel to the transverse direction. Crystal orientation analysis demonstrates a strong compatibility of these proposed processes. Quantitatively separating these different deformation mechanisms is crucial for future predictive modeling of tribological contacts.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2020-02-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record  
  Impact Factor 16.6 Times cited Open Access  
  Notes Approved Most recent IF: 16.6; 2020 IF: 12.124  
  Call Number UA @ admin @ c:irua:183619 Serial 6863  
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Author Chen, B.; Gauquelin, N.; Strkalj, N.; Huang, S.; Halisdemir, U.; Nguyen, M.D.; Jannis, D.; Sarott, M.F.; Eltes, F.; Abel, S.; Spreitzer, M.; Fiebig, M.; Trassin, M.; Fompeyrine, J.; Verbeeck, J.; Huijben, M.; Rijnders, G.; Koster, G. url  doi
openurl 
  Title Signatures of enhanced out-of-plane polarization in asymmetric BaTiO3 superlattices integrated on silicon Type A1 Journal article
  Year 2022 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 13 Issue 1 Pages 265  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract In order to bring the diverse functionalities of transition metal oxides into modern electronics, it is imperative to integrate oxide films with controllable properties onto the silicon platform. Here, we present asymmetric LaMnO<sub>3</sub>/BaTiO<sub>3</sub>/SrTiO<sub>3</sub>superlattices fabricated on silicon with layer thickness control at the unit-cell level. By harnessing the coherent strain between the constituent layers, we overcome the biaxial thermal tension from silicon and stabilize<italic>c</italic>-axis oriented BaTiO<sub>3</sub>layers with substantially enhanced tetragonality, as revealed by atomically resolved scanning transmission electron microscopy. Optical second harmonic generation measurements signify a predominant out-of-plane polarized state with strongly enhanced net polarization in the tricolor superlattices, as compared to the BaTiO<sub>3</sub>single film and conventional BaTiO<sub>3</sub>/SrTiO<sub>3</sub>superlattice grown on silicon. Meanwhile, this coherent strain in turn suppresses the magnetism of LaMnO<sub>3</sub>as the thickness of BaTiO<sub>3</sub>increases. Our study raises the prospect of designing artificial oxide superlattices on silicon with tailored functionalities.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000741852200073 Publication Date 2022-01-11  
  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 16.6 Times cited 11 Open Access OpenAccess  
  Notes This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 823717—ESTEEM3. B.C. is sponsored by Shanghai Sailing Program 21YF1410700. J.V. and N.G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. D.J. acknowledges funding from FWO Project G093417N from the Flemish fund for scientific research. M.T., N.S., M.F.S. and M.F. acknowledge the financial support by the EU European Research Council (Advanced Grant 694955—INSEETO). M.T. acknowledges the Swiss National Science Foundation under Project No. 200021-188414. N.S. acknowledges support under the Swiss National Science Foundation under Project No. P2EZP2-199913. M.S. acknowledges funding from Slovenian Research Agency (Grants No. J2-2510, N2-0149 and P2-0091). B.C. acknowledges Prof. C.D.; Prof. F.Y.; Prof. B.T. and Dr. K.J. for valuable discussions.; esteem3reported; esteem3TA Approved Most recent IF: 16.6  
  Call Number EMAT @ emat @c:irua:185179 Serial 6902  
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Author Toso, S.; Imran, M.; Mugnaioli, E.; Moliterni, A.; Caliandro, R.; Schrenker, N.J.; Pianetti, A.; Zito, J.; Zaccaria, F.; Wu, Y.; Gemmi, M.; Giannini, C.; Brovelli, S.; Infante, I.; Bals, S.; Manna, L. url  doi
openurl 
  Title Halide perovskites as disposable epitaxial templates for the phase-selective synthesis of lead sulfochloride nanocrystals Type A1 Journal article
  Year 2022 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 13 Issue 1 Pages 3976-10  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Colloidal chemistry grants access to a wealth of materials through simple and mild reactions. However, even few elements can combine in a variety of stoichiometries and structures, potentially resulting in impurities or even wrong products. Similar issues have been long addressed in organic chemistry by using reaction-directing groups, that are added to a substrate to promote a specific product and are later removed. Inspired by such approach, we demonstrate the use of CsPbCl3 perovskite nanocrystals to drive the phase-selective synthesis of two yet unexplored lead sulfochlorides: Pb3S2Cl2 and Pb4S3Cl2. When homogeneously nucleated in solution, lead sulfochlorides form Pb3S2Cl2 nanocrystals. Conversely, the presence of CsPbCl3 triggers the formation of Pb4S3Cl2/CsPbCl3 epitaxial heterostructures. The phase selectivity is guaranteed by the continuity of the cationic subnetwork across the interface, a condition not met in a hypothetical Pb3S2Cl2/CsPbCl3 heterostructure. The perovskite domain is then etched, delivering phase-pure Pb4S3Cl2 nanocrystals that could not be synthesized directly. Phase-selective approaches, such using reaction-directing groups, are often seen in traditional organic chemistry and catalysis. Here authors use perovskite nanocrystals as disposable templates to drive the phase-selective synthesis of two colloidal nanomaterials, the lead sulfohalides Pb3S2Cl2 and Pb4S3Cl2.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000825867200003 Publication Date 2022-07-08  
  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 16.6 Times cited 15 Open Access OpenAccess  
  Notes The authors would like to acknowledge Dr. Joka Buha for the help with preliminary tests preceding this project, and Dr. B. M. Aresta and Dr. L. Cassano for their administrative support. The authors acknowledge financial support from the Research Foundation Flanders (FWO) through a postdoctoral fellowship to N.J.S. (FWO Grant No. 1238622N, N.J.S). S.B. acknowledges financial support from the European Commission by ERC Consolidator grant REALNANO (No. 815128, S.B.). L.M. acknowledges financial support from the Italian Ministry of University and Research (MIUR) through the Flag-Era JTC2019 project “Solution-Processed Perovskite/Graphene Nanocomposites for SelfPowered Gas Sensors” (PeroGaS, L.M.). The access to the National Synchrotron Light Source, Brookhaven National Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC0298CH10886 (NSLS-II Proposal Number 307441). Approved Most recent IF: 16.6  
  Call Number UA @ admin @ c:irua:189684 Serial 7085  
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Author Zhang, H.; Pryds, N.; Park, D.-S.; Gauquelin, N.; Santucci, S.; Christensen, D., V.; Jannis, D.; Chezganov, D.; Rata, D.A.; Insinga, A.R.; Castelli, I.E.; Verbeeck, J.; Lubomirsky, I.; Muralt, P.; Damjanovic, D.; Esposito, V. pdf  url
doi  openurl
  Title Atomically engineered interfaces yield extraordinary electrostriction Type A1 Journal article
  Year 2022 Publication Nature Abbreviated Journal  
  Volume 609 Issue 7928 Pages 695-700  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Electrostriction is a property of dielectric materials whereby an applied electric field induces a mechanical deformation proportional to the square of that field. The magnitude of the effect is usually minuscule (<10(-19) m(2) V-2 for simple oxides). However, symmetry-breaking phenomena at the interfaces can offer an efficient strategy for the design of new properties(1,2). Here we report an engineered electrostrictive effect via the epitaxial deposition of alternating layers of Gd2O3-doped CeO2 and Er2O3-stabilized delta-Bi2O3 with atomically controlled interfaces on NdGaO3 substrates. The value of the electrostriction coefficient achieved is 2.38 x 10(-14) m(2) V-2, exceeding the best known relaxor ferroelectrics by three orders of magnitude. Our theoretical calculations indicate that this greatly enhanced electrostriction arises from coherent strain imparted by interfacial lattice discontinuity. These artificial heterostructures open a new avenue for the design and manipulation of electrostrictive materials and devices for nano/micro actuation and cutting-edge sensors.  
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  Publisher Place of Publication Editor  
  Language Wos 000859073900001 Publication Date 2022-09-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1476-4687 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 12 Open Access OpenAccess  
  Notes This research was supported by the BioWings project, funded by the European Union’s Horizon 2020, Future and Emerging Technologies programme (grant no. 801267), and by the Danish Council for Independent Research Technology and Production Sciences for the DFF—Research Project 2 (grant no. 48293). N.P. and D.V.C. acknowledge funding from Villum Fonden for the NEED project (no. 00027993) and from the Danish Council for Independent Research Technology and Production Sciences for the DFF—Research Project 3 (grant no. 00069 B). V.E. acknowledges funding from Villum Fonden for the IRIDE project (no. 00022862). N.G. and J.V. acknowledge funding from the GOA project ('Solarpaint') of the University of Antwerp. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. D.J. acknowledges funding from the FWO Project (no. G093417N) from the Flemish Fund for Scientific Research. D.C. acknowledges TOP/BOF funding from the University of Antwerp. This project has received funding from the European Union’s Horizon 2020 Research Infrastructure—Integrating Activities for Advanced Communities—under grant agreement no. 823717-ESTEEM3. We thank T. D. Pomar and A. J. Bergne for English proofreading.; esteem3reported; esteem3TA Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:190576 Serial 7129  
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Author Wang, D.; Hermes, M.; Najmr, S.; Tasios, N.; Grau-Carbonell, A.; Liu, Y.; Bals, S.; Dijkstra, M.; Murray, C.B.; van Blaaderen, A. url  doi
openurl 
  Title Structural diversity in three-dimensional self-assembly of nanoplatelets by spherical confinement Type A1 Journal article
  Year 2022 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 13 Issue 1 Pages 6001-6012  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Nanoplatelets offer many possibilities to construct advanced materials due to new properties associated with their (semi)two-dimensional shapes. However, precise control of both positional and orientational order of the nanoplatelets in three dimensions, which is required to achieve emerging and collective properties, is challenging to realize. Here, we combine experiments, advanced electron tomography and computer simulations to explore the structure of supraparticles self-assembled from nanoplatelets in slowly drying emulsion droplets. We demonstrate that the rich phase behaviour of nanoplatelets, and its sensitivity to subtle changes in shape and interaction potential can be used to guide the self-assembly into a wide range of different structures, offering precise control over both orientation and position order of the nanoplatelets. Our research is expected to shed light on the design of hierarchically structured metamaterials with distinct shape- and orientation- dependent properties. Nanoplatelets can be used as anisotropic building blocks for constructing novel optoelectronic materials. Here, Wang et al. show a route of assembling nanoplatelets with controllable positional and orientational order in three dimensions facilitated by the surface tension of drying emulsion droplets.  
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  Language Wos 000867312100031 Publication Date 2022-10-12  
  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 16.6 Times cited 7 Open Access OpenAccess  
  Notes We thank A. Kadu, M. Chiappini, F. Rabouw, S. Paliwal, X. Xie, C. Xia and Z. Wang for fruitful discussions. D.W. and A.v.B. acknowledge partial financial support from the European Research Council under the European Union's Seventh Framework Programme (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. M.H. was supported by the Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC). D.W. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 894254 SuprAtom). Y.L. acknowledges the Sustainability project between the faculties of Science and Geosciences of Utrecht University. M.D. acknowledges financial support from European Research Council (Grant No. ERC-2019-ADV-H2020 884902 SoftML). S.B. acknowledges financial support from ERC Consolidator Grant No. 815128 REALNANO. C.B.M. acknowledges support for materials synthesis from the Office of Naval Research Multidisciplinary University Research Initiative Award ONR N00014-18-1-2497. The authors acknowledge the EM square center at Utrecht University for the access to the microscopes. Approved Most recent IF: 16.6  
  Call Number UA @ admin @ c:irua:191387 Serial 7214  
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Author Chen, H.; Xiong, Y.; Li, J.; Abed, J.; Wang, D.; Pedrazo-Tardajos, A.; Cao, Y.; Zhang, Y.; Wang, Y.; Shakouri, M.; Xiao, Q.; Hu, Y.; Bals, S.; Sargent, E.H.H.; Su, C.-Y.; Yang, Z. url  doi
openurl 
  Title Epitaxially grown silicon-based single-atom catalyst for visible-light-driven syngas production Type A1 Journal article
  Year 2023 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 14 Issue 1 Pages 1719-11  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Despite the natural abundance and promising properties of Si, there are few examples of crystalline Si-based catalysts. Here, the authors report an epitaxial growth method to construct Co single atoms on Si for light driven CO2 reduction to syngas. Improving the dispersion of active sites simultaneous with the efficient harvest of photons is a key priority for photocatalysis. Crystalline silicon is abundant on Earth and has a suitable bandgap. However, silicon-based photocatalysts combined with metal elements has proved challenging due to silicon's rigid crystal structure and high formation energy. Here we report a solid-state chemistry that produces crystalline silicon with well-dispersed Co atoms. Isolated Co sites in silicon are obtained through the in-situ formation of CoSi2 intermediate nanodomains that function as seeds, leading to the production of Co-incorporating silicon nanocrystals at the CoSi2/Si epitaxial interface. As a result, cobalt-on-silicon single-atom catalysts achieve an external quantum efficiency of 10% for CO2-to-syngas conversion, with CO and H-2 yields of 4.7 mol g((Co))(-1) and 4.4 mol g((Co))(-1), respectively. Moreover, the H-2/CO ratio is tunable between 0.8 and 2. This photocatalyst also achieves a corresponding turnover number of 2 x 10(4) for visible-light-driven CO2 reduction over 6 h, which is over ten times higher than previously reported single-atom photocatalysts.  
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  Language Wos 000962607600018 Publication Date 2023-03-28  
  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 16.6 Times cited 6 Open Access OpenAccess  
  Notes This work was supported by the National Natural Science Foundation of China (21821003, 21890380, 21905316), Guangdong Natural Science Foundation (2019A1515011748), the Science and Technology Planning Project of Guangdong Province (2019A050510018), Pearl River Recruitment Program of Talent (2019QN01C108), the EU Infrastructure Project EUSMI (Grant No. E190700310), and Sun Yat-sen University. D.W. acknowledges an Individual Fellowship funded by the Marie-Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 894254 SuprAtom). S.B. and A.P.-T. acknowledge financial support from the European Commission under the Horizon 2020 Programme by grant no. 731019 (EUSMI) and ERC Consolidator grant no. 815128 (REALNANO). This project has received funding from the European Commission Grant (EUSMI E190700310). Synchrotron XAS data described in this paper was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation (CFI), the Natural Sciences and Engineering Research Council (NSERC), the National Research Council (NRC), the Canadian Institutes of Health Research (CIHR), the Government of Saskatchewan, and the University of Saskatchewan. Approved Most recent IF: 16.6; 2023 IF: 12.124  
  Call Number UA @ admin @ c:irua:196062 Serial 7932  
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Author Vijayakumar, J.; Savchenko, T.M.; Bracher, D.M.; Lumbeeck, G.; Béché, A.; Verbeeck, J.; Vajda, Š.; Nolting, F.; Vaz, Ca.f.; Kleibert, A. url  doi
openurl 
  Title Absence of a pressure gap and atomistic mechanism of the oxidation of pure Co nanoparticles Type A1 Journal article
  Year 2023 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 14 Issue 1 Pages 174  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Understanding chemical reactivity and magnetism of 3<italic>d</italic>transition metal nanoparticles is of fundamental interest for applications in fields ranging from spintronics to catalysis. Here, we present an atomistic picture of the early stage of the oxidation mechanism and its impact on the magnetism of Co nanoparticles. Our experiments reveal a two-step process characterized by (i) the initial formation of small CoO crystallites across the nanoparticle surface, until their coalescence leads to structural completion of the oxide shell passivating the metallic core; (ii) progressive conversion of the CoO shell to Co<sub>3</sub>O<sub>4</sub>and void formation due to the nanoscale Kirkendall effect. The Co nanoparticles remain highly reactive toward oxygen during phase (i), demonstrating the absence of a pressure gap whereby a low reactivity at low pressures is postulated. Our results provide an important benchmark for the development of theoretical models for the chemical reactivity in catalysis and magnetism during metal oxidation at the nanoscale.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000955726400021 Publication Date 2023-01-12  
  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 16.6 Times cited 1 Open Access OpenAccess  
  Notes Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, 200021160186 2002153540 ; EC | Horizon 2020 Framework Programme, 810310 823717 ; University of Basel | Swiss Nanoscience Institute, P1502 ; This work is funded by Swiss National Foundation (SNF) (Grants. No 200021160186 and 2002153540) and the Swiss Nanoscience Institut (SNI) (Grant No. SNI P1502). S.V. acknowledges support from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 810310, which corresponds to the J. Heyrovsky Chair project (“ERA Chair at J. Heyrovský Institute of Physical Chemistry AS CR – The institutional approach towards ERA”). The funders had no role in the preparation of the article. Part of this work was performed at the Surface/Interface: Microscopy (SIM) beamline of the Swiss Light Source (SLS), Paul Scherrer Institut, Villigen, Switzerland. We kindly acknowledge Anja Weber and Elisabeth Müller from PSI for their help in fabricating the sample markers. A.B. and J. Verbeeck received funding from the European Union’s Horizon 2020 Research Infrastructure – Integrating Activities for Advanced Communities under grant agreement No. 823717 – ESTEEM3 reported Approved Most recent IF: 16.6; 2023 IF: 12.124  
  Call Number EMAT @ emat @c:irua:196738 Serial 8804  
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Author Arteaga Cardona, F.; Jain, N.; Popescu, R.; Busko, D.; Madirov, E.; Arús, B.A.; Gerthsen, D.; De Backer, A.; Bals, S.; Bruns, O.T.; Chmyrov, A.; Van Aert, S.; Richards, B.S.; Hudry, D. pdf  url
doi  openurl
  Title Preventing cation intermixing enables 50% quantum yield in sub-15 nm short-wave infrared-emitting rare-earth based core-shell nanocrystals Type A1 Journal article
  Year 2023 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 14 Issue 1 Pages 4462  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Short-wave infrared (SWIR) fluorescence could become the new gold standard in optical imaging for biomedical applications due to important advantages such as lack of autofluorescence, weak photon absorption by blood and tissues, and reduced photon scattering coefficient. Therefore, contrary to the visible and NIR regions, tissues become translucent in the SWIR region. Nevertheless, the lack of bright and biocompatible probes is a key challenge that must be overcome to unlock the full potential of SWIR fluorescence. Although rare-earth-based core-shell nanocrystals appeared as promising SWIR probes, they suffer from limited photoluminescence quantum yield (PLQY). The lack of control over the atomic scale organization of such complex materials is one of the main barriers limiting their optical performance. Here, the growth of either homogeneous (α-NaYF<sub>4</sub>) or heterogeneous (CaF<sub>2</sub>) shell domains on optically-active α-NaYF<sub>4</sub>:Yb:Er (with and without Ce<sup>3+</sup>co-doping) core nanocrystals is reported. The atomic scale organization can be controlled by preventing cation intermixing only in heterogeneous core-shell nanocrystals with a dramatic impact on the PLQY. The latter reached 50% at 60 mW/cm<sup>2</sup>; one of the highest reported PLQY values for sub-15 nm nanocrystals. The most efficient nanocrystals were utilized for in vivo imaging above 1450 nm.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001037058500022 Publication Date 2023-07-25  
  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 16.6 Times cited 1 Open Access OpenAccess  
  Notes D.H. would like to thank Dominique Ectors (Bruker AXS GmbH, Karlsruhe, Germany) for assistance and discussion on the PXRD data and TOPAS evaluations. The authors would like to acknowledge the financial support provided by the Helmholtz Association via: i) the Professorial Recruitment Initiative Funding (B.S.R.); ii) the Research Field Energy – Program Materials and Technologies for the Energy Transition – Topic 1 Photovoltaics (F.A.C., D.B., E.M., B.S.R., D.H.). This project received funding from the European Union’s Horizon 2020 innovation programme under grant agreement 823717. This work was supported by the European Research Council (grant 770887-PICOMETRICS to S.V.A. and Grant 815128-REALNANO to S.B.). The authors acknowledge financial support from the ResearchFoundation Flanders (FWO, Belgium) through project fundings (G.0346.21 N to S.V.A. and S.B.) and a postdoctoral grant (A.D.B.). The authors (B.A.A., O.T.B. and A.C.) acknowledge funding from the Helmholtz Zentrum München, the DFG-Emmy Noether program (BR 5355/2-1) and from the CZI Deep Tissue Imaging (DTI-0000000248). The authors (O.T.B. and D.H.) would like to thank the Helmholtz Imaging (ZT-I-PF-4-038-BENIGN). Approved Most recent IF: 16.6; 2023 IF: 12.124  
  Call Number EMAT @ emat @c:irua:198158 Serial 8808  
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Author Sasaki, S.; Giri, S.; Cassidy, S.J.; Dey, S.; Batuk, M.; Vandemeulebroucke, D.; Cibin, G.; Smith, R.I.; Holdship, P.; Grey, C.P.; Hadermann, J.; Clarke, S.J. url  doi
openurl 
  Title Anion redox as a means to derive layered manganese oxychalcogenides with exotic intergrowth structures Type A1 Journal article
  Year 2023 Publication Nature communications Abbreviated Journal  
  Volume 14 Issue 1 Pages 2917-11  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Topochemistry enables step-by-step conversions of solid-state materials often leading to metastable structures that retain initial structural motifs. Recent advances in this field revealed many examples where relatively bulky anionic constituents were actively involved in redox reactions during (de)intercalation processes. Such reactions are often accompanied by anion-anion bond formation, which heralds possibilities to design novel structure types disparate from known precursors, in a controlled manner. Here we present the multistep conversion of layered oxychalcogenides Sr(2)MnO(2)Cu(1.5)Ch(2) (Ch=S, Se) into Cu-deintercalated phases where antifluorite type [Cu(1.5)Ch(2)](2.5-) slabs collapsed into two-dimensional arrays of chalcogen dimers. The collapse of the chalcogenide layers on deintercalation led to various stacking types of Sr(2)MnO(2)Ch(2) slabs, which formed polychalcogenide structures unattainable by conventional high-temperature syntheses. Anion-redox topochemistry is demonstrated to be of interest not only for electrochemical applications but also as a means to design complex layered architectures. Low temperature chemical transformations of solids using high-energy intermediates have enabled the synthesis of a new series of layered oxide chalcogenide containing oxidised chalcogenide dimers promising a new range of solids.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001024186000011 Publication Date 2023-05-22  
  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 16.6 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 16.6; 2023 IF: 12.124  
  Call Number UA @ admin @ c:irua:199281 Serial 8832  
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Author Cui, W.; Lin, W.; Lu, W.; Liu, C.; Gao, Z.; Ma, H.; Zhao, W.; Van Tendeloo, G.; Zhao, W.; Zhang, Q.; Sang, X. url  doi
openurl 
  Title Direct observation of cation diffusion driven surface reconstruction at van der Waals gaps Type A1 Journal article
  Year 2023 Publication Nature communications Abbreviated Journal  
  Volume 14 Issue 1 Pages 554-10  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Weak interlayer van der Waals (vdW) bonding has significant impact on the surface/interface structure, electronic properties, and transport properties of vdW layered materials. Unraveling the complex atomistic dynamics and structural evolution at vdW surfaces is therefore critical for the design and synthesis of the next-generation vdW layered materials. Here, we show that Ge/Bi cation diffusion along the vdW gap in layered GeBi2Te4 (GBT) can be directly observed using in situ heating scanning transmission electron microscopy (STEM). The cation concentration variation during diffusion was correlated with the local Te-6 octahedron distortion based on a quantitative analysis of the atomic column intensity and position in time-elapsed STEM images. The in-plane cation diffusion leads to out-of-plane surface etching through complex structural evolutions involving the formation and propagation of a non-centrosymmetric GeTe2 triple layer surface reconstruction on fresh vdW surfaces, and GBT subsurface reconstruction from a septuple layer to a quintuple layer. Our results provide atomistic insight into the cation diffusion and surface reconstruction in vdW layered materials. Weak interlayer van der Waals (vdW) bonding has significant impact on the structure and properties of vdW layered materials. Here authors use in-situ aberration-corrected ADF-STEM for an atomistic insight into the cation diffusion in the vdW gaps and the etching of vdW surfaces at high temperatures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001076227200001 Publication Date 2023-02-02  
  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 16.6 Times cited Open Access  
  Notes Approved Most recent IF: 16.6; 2023 IF: 12.124  
  Call Number UA @ admin @ c:irua:201342 Serial 9021  
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Author Morad, V.; Stelmakh, A.; Svyrydenko, M.; Feld, L.G.; Boehme, S.C.; Aebli, M.; Affolter, J.; Kaul, C.J.; Schrenker, N.J.; Bals, S.; Sahin, Y.; Dirin, D.N.; Cherniukh, I.; Raino, G.; Baumketner, A.; Kovalenko, M.V. url  doi
openurl 
  Title Designer phospholipid capping ligands for soft metal halide nanocrystals Type A1 Journal article
  Year 2024 Publication Nature Abbreviated Journal  
  Volume 626 Issue Pages 542-548  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The success of colloidal semiconductor nanocrystals (NCs) in science and optoelectronics is inextricable from their surfaces. The functionalization of lead halide perovskite NCs1-5 poses a formidable challenge because of their structural lability, unlike the well-established covalent ligand capping of conventional semiconductor NCs6,7. We posited that the vast and facile molecular engineering of phospholipids as zwitterionic surfactants can deliver highly customized surface chemistries for metal halide NCs. Molecular dynamics simulations implied that ligand-NC surface affinity is primarily governed by the structure of the zwitterionic head group, particularly by the geometric fitness of the anionic and cationic moieties into the surface lattice sites, as corroborated by the nuclear magnetic resonance and Fourier-transform infrared spectroscopy data. Lattice-matched primary-ammonium phospholipids enhance the structural and colloidal integrity of hybrid organic-inorganic lead halide perovskites (FAPbBr3 and MAPbBr3 (FA, formamidinium; MA, methylammonium)) and lead-free metal halide NCs. The molecular structure of the organic ligand tail governs the long-term colloidal stability and compatibility with solvents of diverse polarity, from hydrocarbons to acetone and alcohols. These NCs exhibit photoluminescence quantum yield of more than 96% in solution and solids and minimal photoluminescence intermittency at the single particle level with an average ON fraction as high as 94%, as well as bright and high-purity (about 95%) single-photon emission. Phospholipids enhance the structural and colloidal integrity of hybrid organic-inorganic lead halide perovskites and lead-free metal halide nanocrystals, which then exhibit enhanced robustness and optical properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001176943100001 Publication Date 2023-12-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836; 1476-4687 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 64.8 Times cited Open Access  
  Notes Approved Most recent IF: 64.8; 2024 IF: 40.137  
  Call Number UA @ admin @ c:irua:204796 Serial 9144  
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Author Tongay, S.; Sahin, H.; Ko, C.; Luce, A.; Fan, W.; Liu, K.; Zhou, J.; Huang, Y.S.; Ho, C.H.; Yan, J.; Ogletree, D.F.; Aloni, S.; Ji, J.; Li, S.; Li, J.; Peeters, F.M.; Wu, J.; doi  openurl
  Title Monolayer behaviour in bulk ReS2 due to electronic and vibrational decoupling Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 5 Issue Pages 3252  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Semiconducting transition metal dichalcogenides consist of monolayers held together by weak forces where the layers are electronically and vibrationally coupled. Isolated monolayers show changes in electronic structure and lattice vibration energies, including a transition from indirect to direct bandgap. Here we present a new member of the family, rhenium disulphide (ReS2), where such variation is absent and bulk behaves as electronically and vibrationally decoupled monolayers stacked together. From bulk to monolayers, ReS2 remains direct bandgap and its Raman spectrum shows no dependence on the number of layers. Interlayer decoupling is further demonstrated by the insensitivity of the optical absorption and Raman spectrum to interlayer distance modulated by hydrostatic pressure. Theoretical calculations attribute the decoupling to Peierls distortion of the 1T structure of ReS2, which prevents ordered stacking and minimizes the interlayer overlap of wavefunctions. Such vanishing interlayer coupling enables probing of two-dimensional-like systems without the need for monolayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000332666700010 Publication Date 2014-02-06  
  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 806 Open Access  
  Notes ; This work was supported by the United States Department of Energy Early Career Award DE-FG02-11ER46796. The high pressure part of this work was supported by COMPRES, the Consortium for Materials Properties Research in Earth Sciences, under National Science Foundation Cooperative Agreement EAR 11-577758. The electron microscopy and nano-Auger measurements were supported by the user programme at the Molecular Foundry, which was supported by the Office of Science, Office of Basic Energy Sciences, of the United States Department of Energy under contract no. DE-AC02-05CH11231. S. A. gratefully acknowledges Dr Virginia Altoe of the Molecular Foundry for help with the TEM data acquisition and analysis. J.L. acknowledges support from the Natural Science Foundation of China for Distinguished Young Scholar (grant nos. 60925016 and 91233120). Y.-S.H. and C.-H. H. acknowledge support from the National Science Council of Taiwan under project nos. NSC 100-2112-M-011-001-MY3 and NSC 101-2221-E-011-052-MY3. H. S. was supported by the FWO Pegasus Marie Curie Long Fellowship programme. The DFT work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem programme of the Flemish government. Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Centre. ; Approved Most recent IF: 12.124; 2014 IF: 11.470  
  Call Number UA @ lucian @ c:irua:119247 Serial 2192  
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Author Neek-Amal, M.; Xu, P.; Schoelz, J.K.; Ackerman, M.L.; Barber, S.D.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M. doi  openurl
  Title Thermal mirror buckling in freestanding graphene locally controlled by scanning tunnelling microscopy Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 5 Issue Pages 4962  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Knowledge of and control over the curvature of ripples in freestanding graphene are desirable for fabricating and designing flexible electronic devices, and recent progress in these pursuits has been achieved using several advanced techniques such as scanning tunnelling microscopy. The electrostatic forces induced through a bias voltage (or gate voltage) were used to manipulate the interaction of freestanding graphene with a tip (substrate). Such forces can cause large movements and sudden changes in curvature through mirror buckling. Here we explore an alternative mechanism, thermal load, to control the curvature of graphene. We demonstrate thermal mirror buckling of graphene by scanning tunnelling microscopy and large-scale molecular dynamic simulations. The negative thermal expansion coefficient of graphene is an essential ingredient in explaining the observed effects. This new control mechanism represents a fundamental advance in understanding the influence of temperature gradients on the dynamics of freestanding graphene and future applications with electro-thermal-mechanical nanodevices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000342984800018 Publication Date 2014-09-17  
  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 36 Open Access  
  Notes ; Financial support for this study was provided, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M. N.-A.), the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. has also been supported partially by BOF project of University of Antwerp number 28033. ; Approved Most recent IF: 12.124; 2014 IF: 11.470  
  Call Number UA @ lucian @ c:irua:121121 Serial 3628  
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Author Xu, P.; Neek-Amal, M.; Barber, S.D.; Schoelz, J.K.; Ackerman, M.L.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M. doi  openurl
  Title Unusual ultra-low-frequency fluctuations in freestanding graphene Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 5 Issue Pages 3720  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Intrinsic ripples in freestanding graphene have been exceedingly difficult to study. Individual ripple geometry was recently imaged using scanning tunnelling microscopy, but these measurements are limited to static configurations. Thermally-activated flexural phonon modes should generate dynamic changes in curvature. Here we show how to track the vertical movement of a one-square-angstrom region of freestanding graphene using scanning tunnelling microscopy, thereby allowing measurement of the out-of-plane time trajectory and fluctuations over long time periods. We also present a model from elasticity theory to explain the very-low-frequency oscillations. Unexpectedly, we sometimes detect a sudden colossal jump, which we interpret as due to mirror buckling. This innovative technique provides a much needed atomic-scale probe for the time-dependent behaviours of intrinsic ripples. The discovery of this novel progenitor represents a fundamental advance in the use of scanning tunnelling microscopy, which together with the application of a thermal load provides a low-frequency nano-resonator.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000335223200007 Publication Date 2014-04-28  
  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 62 Open Access  
  Notes ; This work was financially supported, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Euro-GRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 12.124; 2014 IF: 11.470  
  Call Number UA @ lucian @ c:irua:117201 Serial 3819  
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Author Buh, J.; Kabanov, V.; Baranov, V.; Mrzel, A.; Kovic, A.; Mihailovic, D. url  doi
openurl 
  Title Control of switching between metastable superconducting states in delta-MoN nanowires Type A1 Journal article
  Year 2015 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 6 Issue 6 Pages 10250  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The superconducting state in one-dimensional nanosystems is very delicate. While fluctuations of the phase of the superconducting wave function lead to the spontaneous decay of persistent supercurrents in thin superconducting wires and nanocircuits, discrete phase-slip fluctuations can also lead to more exotic phenomena, such as the appearance of metastable superconducting states in current-bearing wires. Here we show that switching between different metastable superconducting states in d-MoN nanowires can be very effectively manipulated by introducing small amplitude electrical noise. Furthermore, we show that deterministic switching between metastable superconducting states with different numbers of phase-slip centres can be achieved in both directions with small electrical current pulse perturbations of appropriate polarity. The observed current-controlled bi-stability is in remarkable agreement with theoretically predicted trajectories of the system switching between different limit cycle solutions of a model one-dimensional superconductor.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000367576600002 Publication Date 2015-12-21  
  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 8 Open Access  
  Notes ; ; Approved Most recent IF: 12.124; 2015 IF: 11.470  
  Call Number UA @ lucian @ c:irua:131108 Serial 4156  
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Author Ghorbanfekr-Kalashami, H.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M. url  doi
openurl 
  Title Dependence of the shape of graphene nanobubbles on trapped substance Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue 8 Pages 15844  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Van der Waals (vdW) interaction between two-dimensional crystals (2D) can trap substances in high pressurized (of order 1 GPa) on nanobubbles. Increasing the adhesion between the 2D crystals further enhances the pressure and can lead to a phase transition of the trapped material. We found that the shape of the nanobubble can depend critically on the properties of the trapped substance. In the absence of any residual strain in the top 2D crystal, flat nanobubbles can be formed by trapped long hydrocarbons (that is, hexadecane). For large nanobubbles with radius 130 nm, our atomic force microscopy measurements show nanobubbles filled with hydrocarbons (water) have a cylindrical symmetry (asymmetric) shape which is in good agreement with our molecular dynamics simulations. This study provides insights into the effects of the specific material and the vdW pressure on the microscopic details of graphene bubbles.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000403417500001 Publication Date 2017-06-16  
  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 44 Open Access  
  Notes We acknowledge fruitful discussion with Irina Grigorieva and Andre K. Geim. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program, the Royal Society and the Engineering and Physical Sciences Research Council, UK (EP/K016946/1). M.N.-A. was supported by Iran National Science Foundation (INSF). Approved Most recent IF: 12.124  
  Call Number CMT @ cmt @ c:irua:144189 Serial 4580  
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Author Chirayath, V.A.; Callewaert, V.; Fairchild, A.J.; Chrysler, M.D.; Gladen, R.W.; Mcdonald, A.D.; Imam, S.K.; Shastry, K.; Koymen, A.R.; Saniz, R.; Barbiellini, B.; Rajeshwar, K.; Partoens, B.; Weiss, A.H. pdf  url
doi  openurl
  Title Auger electron emission initiated by the creation of valence-band holes in graphene by positron annihilation Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue 8 Pages 16116  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Auger processes involving the filling of holes in the valence band are thought to make important contributions to the low-energy photoelectron and secondary electron spectrum from many solids. However, measurements of the energy spectrum and the efficiency with which electrons are emitted in this process remain elusive due to a large unrelated background resulting from primary beam-induced secondary electrons. Here, we report the direct measurement of the energy spectra of electrons emitted from single layer graphene as a result of the decay of deep holes in the valence band. These measurements were made possible by eliminating competing backgrounds by employing low-energy positrons (<1.25 eV) to create valence-band holes by annihilation. Our experimental results, supported by theoretical calculations, indicate that between 80 and 100% of the deep valence-band holes in graphene are filled via an Auger transition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000405398200001 Publication Date 2017-07-13  
  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 20 Open Access  
  Notes The experiments in this work were supported by the grant NSF DMR 1508719. A.H.W and A.R.K. gratefully acknowledge support for the building of advanced positron beam through the grant NSF DMR MRI 1338130. V.C. and R.S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. The computational resources and services used in this work were in part provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government (EWI Department). The work at Northeastern University was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences grant number DE-FG02-07ER46352 (core research), and benefited from Northeastern University’s Advanced Scientific Computation Center (ASCC), the NERSC supercomputing center through DOE grant number DE-AC02-05CH11231, and support (applications to layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. Approved Most recent IF: 12.124  
  Call Number CMT @ cmt @ c:irua:144625 Serial 4627  
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Author Wu, K.; Torun, E.; Sahin, H.; Chen, B.; Fan, X.; Pant, A.; Wright, D.P.; Aoki, T.; Peeters, F.M.; Soignard, E.; Tongay, S. url  doi
openurl 
  Title Unusual lattice vibration characteristics in whiskers of the pseudo-one-dimensional titanium trisulfide TiS3 Type A1 Journal article
  Year 2016 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 7 Issue Pages 12952  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Transition metal trichalcogenides form a class of layered materials with strong in-plane anisotropy. For example, titanium trisulfide (TiS3) whiskers are made out of weakly interacting TiS3 layers, where each layer is made of weakly interacting quasi-one-dimensional chains extending along the b axis. Here we establish the unusual vibrational properties of TiS3 both experimentally and theoretically. Unlike other two-dimensional systems, the Raman active peaks of TiS3 have only out-of-plane vibrational modes, and interestingly some of these vibrations involve unique rigid-chain vibrations and S-S molecular oscillations. High-pressure Raman studies further reveal that the A(g)(S-S) S-S molecular mode has an unconventional negative pressure dependence, whereas other peaks stiffen as anticipated. Various vibrational modes are doubly degenerate at ambient pressure, but the degeneracy is lifted at high pressures. These results establish the unusual vibrational properties of TiS3 with strong in-plane anisotropy, and may have relevance to understanding of vibrational properties in other anisotropic two-dimensional material systems.  
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  Language Wos 000385444300004 Publication Date 2016-09-22  
  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 50 Open Access  
  Notes ; S.T. acknowledges support from the National Science Foundation (DMR-1552220) and (CMMI-1561839). F.M.P., H.S. and E.T. were supported by the Flemish Science Foundation (FWO-Vl). Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e Infrastructure). H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP programme. F.P. acknowledges the funding from Flemish Science Foundation (FWO-Vl). K.W. acknowledges helpful discussions with H. Cai, W. Kong and X. Meng. We gratefully acknowledge the use of facilities within the LeRoy Eyring Center for Solid State Science at Arizona State University. ; Approved Most recent IF: 12.124  
  Call Number UA @ lucian @ c:irua:144662 Serial 4700  
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Author Embon, L.; Anahory, Y.; Jelić, Z.L.; Lachman, E.O.; Myasoedov, Y.; Huber, M.E.; Mikitik, G.P.; Silhanek, A.V.; Milošević, M.V.; Gurevich, A.; Zeldov, E. url  doi
openurl 
  Title Imaging of super-fast dynamics and flow instabilities of superconducting vortices Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue Pages 85  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the physics of ultrafast vortices under strong currents remains largely unexplored. Here, we use a nanoscale scanning superconducting quantum interference device to image vortices penetrating into a superconducting Pb film at rates of tens of GHz and moving with velocities of up to tens of km/s, which are not only much larger than the speed of sound but also exceed the pair-breaking speed limit of superconducting condensate. These experiments reveal formation of mesoscopic vortex channels which undergo cascades of bifurcations as the current and magnetic field increase. Our numerical simulations predict metamorphosis of fast Abrikosov vortices into mixed Abrikosov-Josephson vortices at even higher velocities. This work offers an insight into the fundamental physics of dynamic vortex states of superconductors at high current densities, crucial for many applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000405900400002 Publication Date 2017-07-13  
  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 124 Open Access  
  Notes ; We would like to thank M.L. Rappaport for fruitful discussions and technical support. This work was supported by the US-Israel Binational Science Foundation (BSF) grant No. 2014155 and the Israel Science Foundation grant No. 132/14. A.G. was also supported by the United States Department of Energy under Grant No. DE-SC0010081. M.V.M. acknowledges support from Research Foundation-Flanders (FWO). The work of Z.L.J. and A.V.S. was partially supported by “Mandat d'Impulsion Scientifique” MIS F.4527.13 of the F.R.S.-FNRS. This work benefited from the support of COST action MP-1201. ; Approved Most recent IF: 12.124  
  Call Number UA @ lucian @ c:irua:144832 Serial 4720  
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Author Jiang, Y.; Mao, J.; Moldovan, D.; Masir, M.R.; Li, G.; Watanabe, K.; Taniguchi, T.; Peeters, F.M.; Andrei, E.Y. doi  openurl
  Title Tuning a circular p-n junction in graphene from quantum confinement to optical guiding Type A1 Journal article
  Year 2017 Publication Nature nanotechnology Abbreviated Journal Nat Nanotechnol  
  Volume 12 Issue 11 Pages 1045-+  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract <script type='text/javascript'>document.write(unpmarked('The photon-like propagation of the Dirac electrons in graphene, together with its record-high electronic mobility(1-3), can lead to applications based on ultrafast electronic response and low dissipation(4-6). However, the chiral nature of the charge carriers that is responsible for the high mobility also makes it difficult to control their motion and prevents electronic switching. Here, we show how to manipulate the charge carriers by using a circular p-n junction whose size can be continuously tuned from the nanometre to the micrometre scale(7,8). The junction size is controlled with a dual-gate device consisting of a planar back gate and a point-like top gate made by decorating a scanning tunnelling microscope tip with a gold nanowire. The nanometre-scale junction is defined by a deep potential well created by the tip-induced charge. It traps the Dirac electrons in quantum-confined states, which are the graphene equivalent of the atomic collapse states (ACSs) predicted to occur at supercritically charged nuclei(9-13). As the junction size increases, the transition to the optical regime is signalled by the emergence of whispering-gallery modes(14-16), similar to those observed at the perimeter of acoustic or optical resonators, and by the appearance of a Fabry-Perot interference pattern(17-20) for junctions close to a boundary.'));  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000414531800011 Publication Date 2017-09-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-3387; 1748-3395 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 38.986 Times cited 65 Open Access  
  Notes ; The authors acknowledge funding provided by DOE-FG02-99ER45742 (STM/STS) and NSF DMR 1708158 (fabrication). Theoretical work was supported by ESF-EUROCORES-EuroGRAPHENE, FWO VI and the Methusalem program of the Flemish government. ; Approved Most recent IF: 38.986  
  Call Number UA @ lucian @ c:irua:147406 Serial 4902  
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Author Hu, S.; Gopinadhan, K.; Rakowski, A.; Neek-Amal, M.; Heine, T.; Grigorieva, I.V.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. pdf  doi
openurl 
  Title Transport of hydrogen isotopes through interlayer spacing in van der Waals crystals Type A1 Journal article
  Year 2018 Publication Nature nanotechnology Abbreviated Journal Nat Nanotechnol  
  Volume 13 Issue 6 Pages 468-+  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Atoms start behaving as waves rather than classical particles if confined in spaces commensurate with their de Broglie wavelength. At room temperature this length is only about one angstrom even for the lightest atom, hydrogen. This restricts quantum-confinement phenomena for atomic species to the realm of very low temperatures(1-5). Here, we show that van der Waals gaps between atomic planes of layered crystals provide angstrom-size channels that make quantum confinement of protons apparent even at room temperature. Our transport measurements show that thermal protons experience a notably higher barrier than deuterons when entering van der Waals gaps in hexagonal boron nitride and molybdenum disulfide. This is attributed to the difference in the de Broglie wavelengths of the isotopes. Once inside the crystals, transport of both isotopes can be described by classical diffusion, albeit with unexpectedly fast rates comparable to that of protons in water. The demonstrated angstrom-size channels can be exploited for further studies of atomistic quantum confinement and, if the technology can be scaled up, for sieving hydrogen isotopes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000434715700015 Publication Date 2018-04-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-3387; 1748-3395 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 38.986 Times cited 32 Open Access  
  Notes ; The authors acknowledge support from the Lloyd's Register Foundation, EPSRC – EP/N010345/1, the European Research Council ARTIMATTER project – ERC-2012-ADG and from Graphene Flagship. M.L.-H. acknowledges a Leverhulme Early Career Fellowship. ; Approved Most recent IF: 38.986  
  Call Number UA @ lucian @ c:irua:152014UA @ admin @ c:irua:152014 Serial 5046  
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Author Zhou, K.-G.; Vasu, K.S.; Cherian, C.T.; Neek-Amal, M.; Zhang, J.C.; Ghorbanfekr-Kalashami, H.; Huang, K.; Marshall, O.P.; Kravets, V.G.; Abraham, J.; Su, Y.; Grigorenko, A.N.; Pratt, A.; Geim, A.K.; Peeters, F.M.; Novoselov, K.S.; Nair, R.R. pdf  doi
openurl 
  Title Electrically controlled water permeation through graphene oxide membranes Type A1 Journal article
  Year 2018 Publication Nature Abbreviated Journal Nature  
  Volume 559 Issue 7713 Pages 236-+  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Controlled transport of water molecules through membranes and capillaries is important in areas as diverse as water purification and healthcare technologies(1-7). Previous attempts to control water permeation through membranes (mainly polymeric ones) have concentrated on modulating the structure of the membrane and the physicochemical properties of its surface by varying the pH, temperature or ionic strength(3,8). Electrical control over water transport is an attractive alternative; however, theory and simulations(9-14) have often yielded conflicting results, from freezing of water molecules to melting of ice(14-16) under an applied electric field. Here we report electrically controlled water permeation through micrometre-thick graphene oxide membranes(17-21). Such membranes have previously been shown to exhibit ultrafast permeation of water(17,22) and molecular sieving properties(18,21), with the potential for industrial-scale production. To achieve electrical control over water permeation, we create conductive filaments in the graphene oxide membranes via controllable electrical breakdown. The electric field that concentrates around these current-carrying filaments ionizes water molecules inside graphene capillaries within the graphene oxide membranes, which impedes water transport. We thus demonstrate precise control of water permeation, from ultrafast permeation to complete blocking. Our work opens up an avenue for developing smart membrane technologies for artificial biological systems, tissue engineering and filtration.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000438240900052 Publication Date 2018-07-05  
  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 216 Open Access  
  Notes ; This work was supported by the Royal Society, Engineering and Physical Sciences Research Council, UK (EP/K016946/1, EP/N013670/1 and EP/P00119X/1), British Council (award reference number 279336045), European Research Council (contract 679689) and Lloyd's Register Foundation. We thank J. Waters for assisting with X-ray measurements and G. Yu for electrical measurements. ; Approved Most recent IF: 40.137  
  Call Number UA @ lucian @ c:irua:152420UA @ admin @ c:irua:152420 Serial 5096  
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Author Mogg, L.; Hao, G.-P.; Zhang, S.; Bacaksiz, C.; Zou, Y.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. url  doi
openurl 
  Title Atomically thin micas as proton-conducting membranes Type A1 Journal article
  Year 2019 Publication Nature nanotechnology Abbreviated Journal Nat Nanotechnol  
  Volume 14 Issue 10 Pages 962-+  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Monolayers of graphene and hexagonal boron nitride (hBN) are highly permeable to thermal protons1,2. For thicker two-dimensional (2D) materials, proton conductivity diminishes exponentially, so that, for example, monolayer MoS2 that is just three atoms thick is completely impermeable to protons1. This seemed to suggest that only one-atom-thick crystals could be used as proton-conducting membranes. Here, we show that few-layer micas that are rather thick on the atomic scale become excellent proton conductors if native cations are ion-exchanged for protons. Their areal conductivity exceeds that of graphene and hBN by one to two orders of magnitude. Importantly, ion-exchanged 2D micas exhibit this high conductivity inside the infamous gap for proton-conducting materials3, which extends from ∼100 °C to 500 °C. Areal conductivity of proton-exchanged monolayer micas can reach above 100 S cm−2 at 500 °C, well above the current requirements for the industry roadmap4. We attribute the fast proton permeation to ~5-Å-wide tubular channels that perforate micas’ crystal structure, which, after ion exchange, contain only hydroxyl groups inside. Our work indicates that there could be other 2D crystals5 with similar nanometre-scale channels, which could help close the materials gap in proton-conducting applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000488977100016 Publication Date 2019-09-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-3387; 1748-3395 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 38.986 Times cited 37 Open Access  
  Notes ; The work was supported by the Lloyd's Register Foundation, the Engineering and Physical Sciences Research Council (EPSRC)-EP/N010345/1, EP/M010619/1 and EP/ P009050/1, the European Research Council, the Graphene Flagship and the Royal Society. M.L.-H. acknowledges a Leverhulme Early Career Fellowship, G.-P.H. acknowledges a Marie Curie International Incoming Fellowship, and L.M. acknowledges the EPSRC NOWNano programme for funding. Y.Z. acknowledges the assistance of Eric Prestat in TEM specimen preparation. Computational resources were provided by the TUBITAK ULAKBIM High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; Approved Most recent IF: 38.986  
  Call Number UA @ admin @ c:irua:163589 Serial 5407  
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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 Nat Commun  
  Volume 12 Issue 1 Pages 3267  
  Keywords (down) 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  
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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 Nat Commun  
  Volume 12 Issue 1 Pages 7170  
  Keywords (down) 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 10 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:184840 Serial 6989  
Permanent link to this record
 

 
Author Raymenants, E.; Bultynck, O.; Wan, D.; Devolder, T.; Garello, K.; Souriau, L.; Thiam, A.; Tsvetanova, D.; Canvel, Y.; Nikonov, D.E.; Young, I.A.; Heyns, M.; Sorée, B.; Asselberghs, I.; Radu, I.; Couet, S.; Nguyen, V.D. url  doi
openurl 
  Title Nanoscale domain wall devices with magnetic tunnel junction read and write Type A1 Journal article
  Year 2021 Publication Nature Electronics Abbreviated Journal  
  Volume 4 Issue 6 Pages 392-398  
  Keywords (down) A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The manipulation of fast domain wall motion in magnetic nanostructures could form the basis of novel magnetic memory and logic devices. However, current approaches for reading and writing domain walls require external magnetic fields, or are based on conventional magnetic tunnel junctions (MTJs) that are not compatible with high-speed domain wall motion. Here we report domain wall devices based on perpendicular MTJs that offer electrical read and write, and fast domain wall motion via spin-orbit torque. The devices have a hybrid free layer design that consists of platinum/cobalt (Pt/Co) or a synthetic antiferromagnet (Pt/Co/Ru/Co) into the free layer of conventional MTJs. We show that our devices can achieve good tunnelling magnetoresistance readout and efficient spin-transfer torque writing that is comparable to current magnetic random-access memory technology, as well as domain wall depinning efficiency that is similar to stand-alone materials. We also show that a domain wall conduit based on a synthetic antiferromagnet offers the potential for reliable domain wall motion and faster write speed compared with a device based on Pt/Co. Domain wall devices based on perpendicular magnetic tunnel junctions with a hybrid free layer design can offer electrical read and write, and fast domain wall motion driven via spin-orbit torque.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000665011500005 Publication Date 2021-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2520-1131 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:179673 Serial 7003  
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