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Author | Kang, J.; Sahin, H.; Peeters, F.M. | ||||
Title | Tuning carrier confinement in the MoS2/WS2 lateral heterostructure | Type | A1 Journal article | ||
Year | 2015 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 119 | Issue | 119 | Pages | 9580-9586 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | To determine and control the spatial confinement of charge carriers is of importance for nanoscale optoelectronic device applications. Using first-principles calculations, we investigate the tunability of band alignment and Charge localization in lateral and combined lateral vertical heterostructures of MoS2 and WS2. First, we Show that a type-II to type-I band alignment transition takes place when tensile strain is applied on the WS2 region. This band alignment transition is a result of the different response of the band edge states with strain and is caused by their different wave function characters. Then we show that the presence of the grain boundary introduces localized in-gap states. The boundary at the armchair interface significantly modifies the charge distribution of the valence band maximum (VBM) state, whereas in a heterostructure with tilt grain domains both conducation band maximum (CBM) and VBM are found to be localized around the grain boundary. We also found that the thickness of the constituents in a lateral heterostructure also determines how the electrons and holes are confined. Creating combined lateral vertical heterostructures of MOS2/WS2 provides another way cif tuning the charge confinement. These results provide possible ways to tune the carrier confinement in MoS2/WS2 heterostructures, which are interesting for its practical: applications in the future. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000353930700066 | Publication Date | 2015-04-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 73 | Open Access | |
Notes | ; This work was supported by the Methusalem program of the Flemish government. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship and J.K. by a FWO Pegasus Marie Curie-short Fellowship. ; | Approved | Most recent IF: 4.536; 2015 IF: 4.772 | ||
Call Number | c:irua:126381 | Serial | 3747 | ||
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Author | Nourbakhsh, A.; Cantoro, M.; Klekachev, A.; Clemente, F.; Sorée, B.; van der Veen, M.H.; Vosch, T.; Stesmans, A.; Sels, B.; de Gendt, S. | ||||
Title | Tuning the Fermi level of SiO2-supported single-layer graphene by thermal annealing | Type | A1 Journal article | ||
Year | 2010 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
Volume | 114 | Issue | 5 | Pages | 6894-6900 |
Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
Abstract | The effects of thermal annealing in inert Ar gas atmosphere of SiO2-supported, exfoliated single-layer graphene are investigated in this work. A systematic, reproducible change in the electronic properties of graphene is observed after annealing. The most prominent Raman features in graphene, the G and 2D peaks, change in accord to what is expected in the case of hole doping. The results of electrical characterization performed on annealed, back-gated field-effect graphene devices show that the neutrality point voltage VNP increases monotonically with the annealing temperature, confirming the occurrence of excess hole accumulation. No degradation of the structural properties of graphene is observed after annealing at temperatures as high as 400 °C. Thermal annealing of single-layer graphene in controlled Ar atmosphere can therefore be considered a technique to reproducibly modify the electronic structure of graphene by tuning its Fermi level. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000276562500002 | Publication Date | 2010-03-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 54 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2010 IF: 4.524 | |||
Call Number | UA @ lucian @ c:irua:89508 | Serial | 3757 | ||
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Author | Skaltsas, T.; Ke, X.; Bittencourt, C.; Tagmatarchis, N. | ||||
Title | Ultrasonication induces oxygenated species and defects onto exfoliated graphene | Type | A1 Journal article | ||
Year | 2013 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 117 | Issue | 44 | Pages | 23272-23278 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The effect of ultrasonication parameters, such as time and power applied, to exfoliate graphite in o-dichlorobenzene (o-DCB) and N-methyl-1,2-pyrrolidone (NMP) was examined. It was found that the concentration of graphene was higher in o-DCB, while its dispersibility was increased when sonication was applied for a longer period and/or at higher power. However, spectroscopic examination by X-ray photoelectron spectroscopy (XPS) revealed that ultrasonication causes defects and induces oxygen functional groups in the form of carboxylic acids and ethers/epoxides onto the graphene lattice. Additional proof for the latter arose from Raman, IR, and thermogravimetry studies. The carboxylic acids and ethers/epoxides onto exfoliated graphene were derived from air during ultrasonication and found independent of the solvent used for the exfoliation and the power and/or time ultrasonication applied. Quantitative evaluation of the amount of oxygenated species present on exfoliated graphene as performed by high-resolution XPS revealed that the relative oxygen percentage was higher when exfoliation was performed in NMP. Finally, the sonication time and/or power affected the oxygen content on exfoliated graphene, since extended ultrasonication resulted in a decrease in the oxygen content on exfoliated graphene, with a simultaneous increase of defected sp(3) carbon atoms. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000326845400090 | Publication Date | 2013-10-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 65 | Open Access | |
Notes | Approved | Most recent IF: 4.536; 2013 IF: 4.835 | |||
Call Number | UA @ lucian @ c:irua:112710 | Serial | 3797 | ||
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Author | Iyikanat, F.; Sahin, H.; Senger, R.T.; Peeters, F.M. | ||||
Title | Vacancy formation and oxidation characteristics of single layer TiS3 | Type | A1 Journal article | ||
Year | 2015 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 119 | Issue | 119 | Pages | 10709-10715 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | The structural, electronic, and magnetic properties of pristine, defective, and oxidized monolayer TiS3 are investigated using first-principles calculations in the framework of density functional theory. We found that a single layer of TiS3 is a direct band gap semiconductor, and the bonding nature of the crystal is fundamentally different from other transition metal chalcogenides. The negatively charged surfaces of single layer TiS3 makes this crystal a promising material for lubrication applications. The formation energies of possible vacancies, i.e. S, Ti, TiS, and double S, are investigated via total energy optimization calculations. We found that the formation of a single S vacancy was the most likely one among the considered vacancy types. While a single S vacancy results in a nonmagnetic, semiconducting character with an enhanced band gap, other vacancy types induce metallic behavior with spin polarization of 0.3-0.8 mu(B). The reactivity of pristine and defective TiS3 crystals against oxidation was investigated using conjugate gradient calculations where we considered the interaction with atomic O, O-2, and O-3. While O-2 has the lowest binding energy with 0.05-0.07 eV, O-3 forms strong bonds stable even at moderate temperatures. The strong interaction (3.9-4.0 eV) between atomic O and TiS3 results in dissociative adsorption of some O-containing molecules. In addition, the presence of S-vacancies enhances the reactivity of the surface with atomic O, whereas it had a negative effect on the reactivity with O-2 and O-3 molecules. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000354912200063 | Publication Date | 2015-04-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 51 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. RI., H.S., and R.T.S. acknowledge the support from TUBITAK through project 114F397. ; | Approved | Most recent IF: 4.536; 2015 IF: 4.772 | ||
Call Number | c:irua:126410 | Serial | 3829 | ||
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Author | de Backer, J.W.; Vos, W.G.; Burnell, P.; Verhulst, S.L.; Salmon, P.; de Clerck, N.; de Backer, W. | ||||
Title | Study of the variability in upper and lower airway morphology in Sprague-Dawley rats using modern micro-CT scan-based segmentation techniques | Type | A1 Journal article | ||
Year | 2009 | Publication | The anatomical record: advances in integrative anatomy and evolutionary biology | Abbreviated Journal | Anat Rec |
Volume | 292 | Issue | 5 | Pages | 720-727 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
Abstract | Animal models are being used extensively in pre-clinical and safety assessment studies to assess the effectiveness and safety of new chemical entities and delivery systems. Although never entirely replacing the need for animal testing, the use of computer simulations could eventually reduce the amount of animals needed for research purposes and refine the data acquired from the animal studies. Computational fluid dynamics is a powerful tool that makes it possible to simulate flow and particle behavior in animal or patient-specific respiratory models, for purposes of inhaled delivery. This tool requires an accurate representation of the respiratory system, respiration and dose delivery attributes. The aim of this study is to develop a representative airway model of the Sprague-Dawley rat using static and dynamic micro-CT scans. The entire respiratory tract was modeled, from the snout and nares down to the central airways at the point where no distinction could be made between intraluminal air and the surrounding tissue. For the selection of the representative model, variables such as upper airway movement, segmentation length, airway volume and size are taken into account. Dynamic scans of the nostril region were used to illustrate the characteristic morphology of this region in anaesthetized animals. It could be concluded from this study that it was possible to construct a highly detailed representative model of a Sprague-Dawley rat based on imaging modalities such as micro-CT scans | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000265766000010 | Publication Date | 2009-03-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-8486;1932-8494; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.431 | Times cited | 16 | Open Access | |
Notes | Approved | Most recent IF: 1.431; 2009 IF: 1.490 | |||
Call Number | UA @ lucian @ c:irua:76455 | Serial | 3342 | ||
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Author | Khosravian, N.; Bogaerts, A.; Huygh, S.; Yusupov, M.; Neyts, E.C. | ||||
Title | How do plasma-generated OH radicals react with biofilm components? Insights from atomic scale simulations | Type | A1 Journal article | ||
Year | 2015 | Publication | Biointerphases | Abbreviated Journal | Biointerphases |
Volume | 10 | Issue | 10 | Pages | 029501 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The application of nonthermal atmospheric pressure plasma is emerging as an alternative and efficient technique for the inactivation of bacterial biofilms. In this study, reactive molecular dynamics simulations were used to examine the reaction mechanisms of hydroxyl radicals, as key reactive oxygen plasma species in biological systems, with several organic molecules (i.e., alkane, alcohol, carboxylic acid, and amine), as prototypical components of biomolecules in the biofilm. Our results demonstrate that organic molecules containing hydroxyl and carboxyl groups may act as trapping agents for the OH radicals. Moreover, the impact of OH radicals on N-acetyl-glucosamine, as constituent component of staphylococcus epidermidis biofilms, was investigated. The results show how impacts of OH radicals lead to hydrogen abstraction and subsequent molecular damage. This study thus provides new data on the reaction mechanisms of plasma species, and particularly the OH radicals, with fundamental components of bacterial biofilms. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000357195600019 | Publication Date | 2014-12-17 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1934-8630;1559-4106; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.603 | Times cited | 10 | Open Access | |
Notes | Approved | Most recent IF: 2.603; 2015 IF: 3.374 | |||
Call Number | c:irua:121371 | Serial | 1492 | ||
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Author | Wende, K.; Williams, P.; Dalluge, J.; Van Gaens, W.; Aboubakr, H.; Bischof, J.; von Woedtke, T.; Goyal, S.M.; Weltmann, K.D.; Bogaerts, A.; Masur, K.; Bruggeman, P.J.; | ||||
Title | Identification of the biologically active liquid chemistry induced by a nonthermal atmospheric pressure plasma jet | Type | A1 Journal article | ||
Year | 2015 | Publication | Biointerphases | Abbreviated Journal | Biointerphases |
Volume | 10 | Issue | 10 | Pages | 029518 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The mechanism of interaction of cold nonequilibrium plasma jets with mammalian cells in physiologic liquid is reported. The major biological active species produced by an argon RF plasma jet responsible for cell viability reduction are analyzed by experimental results obtained through physical, biological, and chemical diagnostics. This is complemented with chemical kinetics modeling of the plasma source to assess the dominant reactive gas phase species. Different plasma chemistries are obtained by changing the feed gas composition of the cold argon based RF plasma jet from argon, humidified argon (0.27%), to argon/oxygen (1%) and argon/air (1%) at constant power. A minimal consensus physiologic liquid was used, providing isotonic and isohydric conditions and nutrients but is devoid of scavengers or serum constituents. While argon and humidified argon plasma led to the creation of hydrogen peroxide dominated action on the mammalian cells, argonoxygen and argonair plasma created a very different biological action and was characterized by trace amounts of hydrogen peroxide only. In particular, for the argonoxygen (1%), the authors observed a strong negative effect on mammalian cell proliferation and metabolism. This effect was distance dependent and showed a half life time of 30 min in a scavenger free physiologic buffer. Neither catalase and mannitol nor superoxide dismutase could rescue the cell proliferation rate. The strong distance dependency of the effect as well as the low water solubility rules out a major role for ozone and singlet oxygen but suggests a dominant role of atomic oxygen. Experimental results suggest that O reacts with chloride, yielding Cl2 − or ClO−. These chlorine species have a limited lifetime under physiologic conditions and therefore show a strong time dependent biological activity. The outcomes are compared with an argon MHz plasma jet (kinpen) to assess the differences between these (at least seemingly) similar plasma sources. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000357195600036 | Publication Date | 2015-05-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1934-8630;1559-4106; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.603 | Times cited | 137 | Open Access | |
Notes | Approved | Most recent IF: 2.603; 2015 IF: 3.374 | |||
Call Number | c:irua:126774 | Serial | 1549 | ||
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Author | Neek-Amal, M.; Peeters, F.M.; Grigorieva, I.V.; Geim, A.K. | ||||
Title | Commensurability Effects in Viscosity of Nanoconfined Water | Type | A1 Journal article | ||
Year | 2016 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 10 | Issue | 10 | Pages | 3685-3692 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | The rate of water flow through hydrophobic nanocapillaries is greatly enhanced as compared to that expected from macroscopic hydrodynamics. This phenomenon is usually described in terms of a relatively large slip length, which is in turn defined by such microscopic properties as the friction between water and capillary surfaces and the viscosity of water. We show that the viscosity of water and, therefore, its flow rate are profoundly affected by the layered structure of confined water if the capillary size becomes less than 2 nm. To this end, we study the structure and dynamics of water confined between two parallel graphene layers using equilibrium molecular dynamics simulations. We find that the shear viscosity is not only greatly enhanced for subnanometer capillaries, but also exhibits large oscillations that originate from commensurability between the capillary size and the size of water molecules. Such oscillating behavior of viscosity and, consequently, the slip length should be taken into account in designing and studying graphene-based and similar membranes for desalination and filtration. | ||||
Address | School of Physics and Astronomy, University of Manchester , Manchester M13 9PL, United Kingdom | ||||
Corporate Author | Thesis | ||||
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Language | English | Wos | 000372855400073 | Publication Date | 2016-02-16 |
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ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 160 | Open Access | |
Notes | ; M.N.A. was support by Shahid Rajaee Teacher Training University under contract number 29605. ; | Approved | Most recent IF: 13.942 | ||
Call Number | c:irua:133237 | Serial | 4012 | ||
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Author | Altantzis, T.; Coutino-Gonzalez, E.; Baekelant, W.; Martinez, G.T.; Abakumov, A.M.; Van Tendeloo, G.; Roeffaers, M.B.J.; Bals, S.; Hofkens, J. | ||||
Title | Direct Observation of Luminescent Silver Clusters Confined in Faujasite Zeolites | Type | A1 Journal article | ||
Year | 2016 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 10 | Issue | 10 | Pages | 7604-7611 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | One of the ultimate goals in the study of metal clusters is the correlation between the atomic-scale organization and their physicochemical properties. However, direct observation of the atomic organization of such minuscule metal clusters is heavily hindered by radiation damage imposed by the different characterization techniques. We present direct evidence of the structural arrangement, at an atomic level, of luminescent silver species stabilized in faujasite (FAU) zeolites using aberration-corrected scanning transmission electron microscopy. Two different silver clusters were identified in Ag-FAU zeolites, a trinuclear silver species associated with green emission and a tetranuclear silver species related to yellow emission. By combining direct imaging with complementary information obtained from X-ray powder diffraction and Rietveld analysis, we were able to elucidate the main differences at an atomic scale between luminescent (heat-treated) and nonluminescent (cation-exchanged) Ag-FAU zeolites. It is expected that such insights will trigger the directed synthesis of functional metal nanocluster-zeolite composites with tailored luminescent properties. | ||||
Address | RIES, Hokkaido University , N20W10, Kita-Ward Sapporo 001-0020, Japan | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000381959100043 | Publication Date | 2016-07-08 |
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Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 57 | Open Access | OpenAccess |
Notes | The authors gratefully acknowledge financial support from the Belgian Federal government (Belspo through the IAP-VI/27 and IAP-VII/05 programs), the European Union’s Seventh Framework Programme (FP7/2007-2013 under grant agreement no. 310651 SACS and no. 312483-ESTEEM2), the Flemish government in the form of long-term structural funding “Methusalem” grant METH/15/04 CASAS2, the Hercules foundation (HER/11/14), the “Strategisch Initiatief Materialen” SoPPoM program, and the Fund for Scientific Research Flanders (FWO) grants G.0349.12 and G.0B39.15. S.B. acknowledges funding from ERC Starting Grant COLOURATOMS (335078). The authors thank Prof. S. Van Aert for helpful discussions, Dr. T. De Baerdemaeker for XRD measurements, Mr. B. Dieu for the preparation of graphical material, and UOP Antwerp for the kind donation of zeolite samples.; esteem2jra4; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 13.942 | ||
Call Number | c:irua:134576 c:irua:134576 | Serial | 4102 | ||
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Author | Schouteden, K.; Govaerts, K.; Debehets, J.; Thupakula, U.; Chen, T.; Li, Z.; Netsou, A.; Song, F.; Lamoen, D.; Van Haesendonck, C.; Partoens, B.; Park, K. | ||||
Title | Annealing-Induced Bi Bilayer on Bi2Te3 Investigated via Quasi-Particle-Interference Mapping | Type | A1 Journal article | ||
Year | 2016 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 10 | Issue | 10 | Pages | 8778-8787 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Topological insulators (TIs) are renowned for their exotic topological surface states (TSSs) that reside in the top atomic layers, and hence, detailed knowledge of the surface top atomic layers is of utmost importance. Here we present the remarkable morphology changes of Bi2Te3 surfaces, which have been freshly cleaved in air, upon subsequent systematic annealing in ultrahigh vacuum and the resulting effects on the local and area-averaging electronic properties of the surface states, which are investigated by combining scanning tunneling microscopy (STM), scanning tunneling spectroscopy (STS), and Auger electron spectroscopy (AES) experiments with density functional theory (DFT) calculations. Our findings demonstrate that the annealing induces the formation of a Bi bilayer atop the Bi2Te3 surface. The adlayer results in n-type doping, and the atomic defects act as scattering centers of the TSS electrons. We also investigated the annealing-induced Bi bilayer surface on Bi2Te3 via voltage-dependent quasi-particle-interference (QPI) mapping of the surface local density of states and via comparison with the calculated constant-energy contours and QPI patterns. We observed closed hexagonal patterns in the Fourier transform of real-space QPI maps with secondary outer spikes. DFT calculations attribute these complex QPI patterns to the appearance of a “second” cone due to the surface charge transfer between the Bi bilayer and the Bi2Te3. Annealing in ultrahigh vacuum offers a facile route for tuning of the topological properties and may yield similar results for other topological materials. | ||||
Address | Department of Physics, Virginia Tech , Blacksburg, Virginia 24061, United States | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000384399300073 | Publication Date | 2016-09-02 |
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ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 15 | Open Access | |
Notes | The research in Leuven and Antwerp was supported by the Research FoundationFlanders (FWO, Belgium). The research in Leuven received additional support from the Flemish Concerted Research Action Program (BOF KULeuven, Project GOA/14/007) and the KULeuven Project GOA “Fundamental Challenges in Semiconductor Research”. Z.L. acknowledges the support from the China Scholarship Council (2011624021) and from KU Leuven Internal Funds (PDM). K.S. and J.D. acknowledge additional support from the FWO. T.C. and F.S. acknowledge the financial support of the National Key Projects for Basic Research of China (Grants 2013CB922103 and 2011CB922103), the National NaturalScience Foundation of China (Grant s 91421109, 11134005,11522432, and 11274003), the Natural Science Foundation ofJiangsu Province (Grant BK20130054), and the FundamentalResearch Funds for the Central Universities. K.P. wassupported by the U.S. National Science Foundation (DMR-1206354) and San Diego Supercomputer Center (SDSC)Comet and Gordon (DMR060009N). | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @ c:irua:136269 | Serial | 4294 | ||
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Author | Zhang, L.; Lin, B.-C.; Wu, Y.-F.; Wu, H.; Huang, T.-W.; Chang, C.-R.; Ke, X.; Kurttepeli, M.; Tendeloo, G.V.; Xu, J.; Yu, D.; Liao, Z.-M. | ||||
Title | Electronic Coupling between Graphene and Topological Insulator Induced Anomalous Magnetotransport Properties | Type | A1 Journal article | ||
Year | 2017 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 11 | Issue | 11 | Pages | 6277-6285 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | It has been theoretically proposed that the spin textures of surface states in a topological insulator can be directly transferred to graphene by means of the proximity effect, which is very important for realizing the two-dimensional topological insulator based on graphene. Here we report the anomalous magnetotransport properties of graphene-topological insulator Bi2Se3 heterojunctions, which are sensitive to the electronic coupling between graphene and the topological surface state. The coupling between the p_z orbitals of graphene and the p orbitals of the surface states on the Bi2Se3 bottom surface can be enhanced by applying a perpendicular negative magnetic field, resulting in a giant negative magnetoresistance at the Dirac point up to about -91%. Obvious resistances dip in the transfer curve at the Dirac point is also observed in the hybrid devices, which is consistent with theoretical predictions of the distorted Dirac bands with nontrivial spin textures inherited from the Bi2Se3 surface states. | ||||
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Language | Wos | 000404808000110 | Publication Date | 2017-05-10 | |
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ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 12 | Open Access | OpenAccess |
Notes | ; This work was supported by National Key Research and Development Program of China (Nos. 2016YFA0300802, 2013CB934600) and NSFC (No. 11234001). ; | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @ c:irua:143192 | Serial | 4569 | ||
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Author | Montanarella, F.; Altantzis, T.; Zanaga, D.; Rabouw, F.T.; Bals, S.; Baesjou, P.; Vanmaekelbergh, D.; van Blaaderen, A. | ||||
Title | Composite Supraparticles with Tunable Light Emission | Type | A1 Journal article | ||
Year | 2017 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 11 | Issue | 11 | Pages | 9136-9142 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Robust luminophores emitting light with broadly tunable colors are desirable in many applications such as light-emitting diode (LED)-based lighting, displays, integrated optoelectronics and biology. Nanocrystalline quantum dots with multicolor emission, from core- and shell-localized excitons, as well as solid layers of mixed quantum dots that emit different colors have been proposed. Here, we report on colloidal supraparticles that are composed of three types of Cd(Se,ZnS) core/(Cd,Zn)S shell nanocrystals with emission in the red, green, and blue. The emission of the supraparticles can be varied from pure to composite colors over the entire visible region and finetuned into variable shades of white light by mixing the nanocrystals in controlled proportions. Our approach results in supraparticles with sizes spanning the colloidal domain and beyond that combine versatility and processability with a broad, stable, and tunable emission, promising applications in lighting devices and biological research. | ||||
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Language | Wos | 000411918200062 | Publication Date | 2017-09-26 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 36 | Open Access | OpenAccess |
Notes | We thank J. J. Geuchies for help with the optical analysis, W. Vlug for providing silica particles filled with RITC, J. D. Meeldijk for his assistance with SE-STEM measurements, E. B. van der Wee for help with the calculation of the radial distribution functions, and M. van Huis and S. Dussi for very fruitful discussions. This work was supported by the European Comission via the Marie-Sklodowska Curie action Phonsi (H2020-MSCA-ITN-642656). D.V. wishes to thank the Dutch FOM (program DDC13), NWO−CW (Toppunt 718.015.002), and the European Research Council under HORIZON 2020 (grant 692691 FIRSTSTEP) for financial support. A.v.B. and F.M. acknowledge partial funding from the European Research Council under the European Union’s Seventh Framework Programme (FP-2007-2013)/ERC advanced grant agreement 291667: HierarSACol. S.B. and D.Z. acknowledge financial support from the European Research Council (starting grant no. COLOURATOM 335078), and T.A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. ECAS_Sara (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:146095UA @ admin @ c:irua:146095 | Serial | 4732 | ||
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Author | Fedoseeva, Y.V.; Orekhov, A.S.; Chekhova, G.N.; Koroteev, V.O.; Kanygin, M.A.; Seovskiy, B.V.; Chuvilin, A.; Pontiroli, D.; Ricco, M.; Bulusheva, L.G.; Okotrub, A.V. | ||||
Title | Single-walled carbon nanotube reactor for redox transformation of mercury dichloride | Type | A1 Journal article | ||
Year | 2017 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 11 | Issue | 9 | Pages | 8643-8649 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | <script type='text/javascript'>document.write(unpmarked('Single-walled carbon nanotubes (SWCNTs) possessing a confined inner space protected by chemically resistant shells are promising for delivery, storage, and desorption of various compounds, as well as carrying out specific reactions. Here, we show that SWCNTs interact with molten mercury dichloride (HgCl2) and guide its transformation into dimercury dichloride (Hg2Cl2) in the cavity. The chemical state of host SWCNTs remains almost unchanged except for a small p-doping from the guest Hg2Cl2 nanocrystals. The density functional theory calculations reveal that the encapsulated HgCl2 molecules become negatively charged and start interacting via chlorine bridges when local concentration increases. This reduces the bonding strength in HgCl2, which facilitates removal of chlorine, finally leading to formation of Hg2Cl2 species. The present work demonstrates that SWCNTs not only serve as a template for growing nanocrystals but also behave as an electron-transfer catalyst in the spatially confined redox reaction by donation of electron density for temporary use by the guests.')); | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000411918200012 | Publication Date | 2017-08-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 11 | Open Access | Not_Open_Access |
Notes | ; Collaboration between partner institutions was partially supported by European FP7 IRSES project 295180. We are grateful to the bilateral Program “Russian-German Laboratory at BESSY II” for the assistance in XPS and NEXAFS measurements. We acknowledge C. Tollan for proofreading the manuscript. We are grateful to Dr. Y.V. Shubin for XRD measurements of graphite with HgCl<INF>2</ INF>. ; | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ lucian @ c:irua:146770 | Serial | 4895 | ||
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Author | Sandoval, S.; Kepic, D.; Perez del Pino, A.; Gyorgy, E.; Gomez, A.; Pfannmöller, M.; Van Tendeloo, G.; Ballesteros, B.; Tobias, G. | ||||
Title | Selective laser-assisted synthesis of tubular van der Waals heterostructures of single-layered PbI2 within carbon nanotubes exhibiting carrier photogeneration | Type | A1 Journal article | ||
Year | 2018 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 12 | Issue | 7 | Pages | 6648-6656 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The electronic and optical properties of two-dimensional layered materials allow the miniaturization of nanoelectronic and optoelectronic devices in a competitive manner. Even larger opportunities arise when two or more layers of different materials are combined. Here, we report on an ultrafast energy efficient strategy, using laser irradiation, which allows bulk synthesis of crystalline single-layered lead iodide in the cavities of carbon nanotubes by forming cylindrical van der Waals heterostructures. In contrast to the filling of van der Waals solids into carbon nanotubes by conventional thermal annealing, which favors the formation of inorganic nanowires, the present strategy is highly selective toward the growth of monolayers forming lead iodide nanotubes. The irradiated bulk material bearing the nanotubes reveals a decrease of the resistivity as well as a significant increase in the current flow upon illumination. Both effects are attributed to the presence of single-walled lead iodide nanotubes in the cavities of carbon nanotubes, which dominate the properties of the whole matrix. The present study brings in a simple, ultrafast and energy efficient strategy for the tailored synthesis of rolled-up single-layers of lead iodide (i.e., single-walled PbI2 nanotubes), which we believe could be expanded to other two-dimensional (2D) van der Waals solids. In fact, initial tests with ZnI2 already reveal the formation of single-walled ZnI2 nanotubes, thus proving the versatility of the approach. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000440505000029 | Publication Date | 2018-07-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 8 | Open Access | OpenAccess |
Notes | ; We acknowledge funding from MINECO (Spain), through MAT2017-86616-R, ENE2017-89210-C2-1-R, and “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0496, SEV-2013-0295), CERCA programme for funding ICN2 and support from AGAUR of Generalitat de Catalunya through the projects 2017 SGR 1086, 2017 SGR 581 and 2017 SGR 327. We thank Thomas Swan Co., Ltd., for supplying MWCNT Elicarb samples. D.K. acknowledges financial support from the Ministry of Education, Science, and Technological Development of the Republic of Serbia for postdoctoral research. We are grateful to R Rurali (ICMAB-CSIC) for providing the structural model of the PbI<INF>2</INF> nanotube employed for the schematic representation of PbI<INF>2</INF>@MVWCNT. ; | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ lucian @ c:irua:153169 | Serial | 5127 | ||
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Author | Feld, A.; Weimer, A.; Kornowski, A.; Winckelmans, N.; Merkl, J.-P.; Kloust, H.; Zierold, R.; Schmidtke, C.; Schotten, T.; Riedner, M.; Bals, S.; Weller, P.D., Horst | ||||
Title | Chemistry of Shape-Controlled Iron Oxide Nanocrystal Formation | Type | A1 Journal article | ||
Year | 2018 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 13 | Issue | 13 | Pages | 152-162 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Herein we demonstrate that meticulous and in-depth analysis of the reaction mechanisms of nanoparticle formation is rewarded by full control of size, shape and crystal structure of superparamagnetic iron oxide nanocrystals during synthesis. Starting from two iron sources – iron(II)- and iron(III) carbonate -a strict separation of oleate formation from the generation of reactive pyrolysis products and concomitant nucleation of iron oxide nanoparticles was achieved. This protocol enabled us to analyze each step of nanoparticle formation independently in depth. Progress of the entire reaction was monitored via matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and gas chromatography (GC) gaining insight into the formation of various iron oleate species prior to nucleation. Interestingly, due to the intrinsic strongly reductive pyrolysis conditions of the oleate intermediates and redox process in early stages of the synthesis, pristine iron oxide nuclei were composed exclusively from wustite, irrespective of the oxidation state of the iron source. Controlling the reaction conditions provided a very broad range of size- and shape defined monodisperse iron oxide nanoparticles. Curiously, after nucleation star shaped nanocrystals were obtained, which underwent metamorphism towards cubic shaped particles. EELS tomography revealed ex post oxidation of the primary wustite nanocrystal providing a full 3D image of Fe2+ and Fe3+ distribution within. Overall, we developed a highly flexible synthesis, yielding multigram amounts of well-defined iron oxide nanocrystals of different sizes and morphologies. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000456749900017 | Publication Date | 2018-12-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 54 | Open Access | OpenAccess |
Notes | The authors gratefully acknowledge financial support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Projektnummer 192346071 – SFB 986 and the excellence cluster ‘The Hamburg Centre for Ultrafast Imaging – Structure, Dynamics and Control of Matter at the Atomic Scale’ (by grant EXC 1074) S.B. and N.W. acknowledge financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS) and from the Research Foundation Flanders (FWO, Belgium) through Project fundings G038116N. Dr. Volker Sauerland for his support in calibrating the MALDI-TOF spectra. Almut Bark for measuring XRD (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ecas_sara | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:155716UA @ admin @ c:irua:155716 | Serial | 5073 | ||
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Author | Gonzalez-Rubio, G.; Kumar, V.; Llombart, P.; Diaz-Nunez, P.; Bladt, E.; Altantzis, T.; Bals, S.; Pena-Rodriguez, O.; Noya, E.G.; MacDowell, L.G.; Guerrero-Martinez, A.; Liz-Marzan, L.M. | ||||
Title | Disconnecting Symmetry Breaking from Seeded Growth for the Reproducible Synthesis of High Quality Gold Nanorods | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 13 | Issue | 13 | Pages | 4424-4435 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | One of the major difficulties hindering the widespread application of colloidal anisotropic plasmonic nanoparticles is the limited robustness and reproducibility of multistep synthetic methods. We demonstrate herein that the reproducibility and reliability of colloidal gold nanorod (AuNR) synthesis can be greatly improved by disconnecting the symmetry-breaking event from the seeded growth process. We have used a modified silver-assisted seeded growth method in the presence of the surfactant hexadecyltrimethylammonium bromide and n-decanol as a co-surfactant to prepare small AuNRs in high yield, which were then used as seeds for the growth of high quality AuNR colloids. Whereas the use of n-decanol provides a more-rigid micellar system, the growth on anisotropic seeds avoids sources of irreproducibility during the symmetry breaking step, yielding uniform AuNR colloids with narrow plasmon bands, ranging from 600 to 1270 nm, and allowing the fine-tuning of the final dimensions. This method provides a robust route for the preparation of high quality AuNR colloids with tunable morphology, size, and optical response in a reproducible and scalable manner. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000466052900067 | Publication Date | 2019-04-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 100 | Open Access | OpenAccess |
Notes | ; This work has been funded by the Spanish MINECO (grant nos. FIS2017-89361-C3-2-P and MAT2017-86659-R), the Madrid Regional Government (grant no. P2018/NMT-4389) and the Complutense University of Madrid (grant no. PR75/18-21616). Funding is acknowledged from the European Commission (grant no. EUSMI 731019). G.G.-R. acknowledges receipt of FPI Fellowship from the Spanish MINECO. E.B. and T.A. acknowledge postdoctoral grants from the Research Foundation Flanders (FWO). The authors are indebted to Profs. Justin Gooding, Watson Loh, Nicholas Kotov, Deqing Zhang, Mihaela Delcea, Maurizio Prato, and Krishna Ganesh, for providing milli-Q water samples. ; | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:160417 | Serial | 5246 | ||
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Author | Jishkariani, D.; Elbert, K.C.; Wu, Y.; Lee, J.D.; Hermes, M.; Wang, D.; van Blaaderen, A.; Murray, C.B. | ||||
Title | Nanocrystal Core Size and Shape Substitutional Doping and Underlying Crystalline Order in Nanocrystal Superlattices | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 13 | Issue | 5 | Pages | 5712-5719 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Substitutional doping is a potentially powerful technique to control the properties of nanocrystal (NC) superlattices (SLs). However, not every NC can be substituted into any lattice, as the NCs have to be close in size and shape, limiting the application of substitutional doping. Here we show that this limitation can be overcome by employing ligands of various size. We show that small NCs with long ligands can be substituted into SLs of big NCs with short ligands. Furthermore, we show that shape differences can also be overcome and that cubes can substitute spheres when both are coated with long ligands. Finally, we use the NC effective ligand size, softness, and effective overall size ratio to explain observed doping behaviors. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000469886300078 | Publication Date | 2019-05-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 6 | Open Access | Not_Open_Access |
Notes | ; This work was supported by the University of Pennsylvania's NSF MRSEC under award no. DMR-112090 and the CNRS-UPENN-SOLVAY through the Complex Assemblies of Soft Matter Laboratory (COMPASS). K.C.E. acknowledges support from the NSF Graduate Research Fellowship Program under grant no. DGE-1321851. C.B.M. acknowledges the Richard Perry University Professorship at the University of Pennsylvania. D.W. and A.v.B. acknowledge partial funding 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), an NWO Gravitation programme funded by the Ministry of Education, Culture and Science of the government of The Netherlands. The authors thank EM square in Utrecht University for the access to the microscopes. ; | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:160344 | Serial | 5256 | ||
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Author | Albrecht, W.; Bladt, E.; Vanrompay, H.; Smith, J.D.; Skrabalak, S.E.; Bals, S. | ||||
Title | Thermal Stability of Gold/Palladium Octopods Studied in Situ in 3D: Understanding Design Rules for Thermally Stable Metal Nanoparticles | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 13 | Issue | 13 | Pages | 6522-6530 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Multifunctional metal nanoparticles (NPs) such as anisotropic multimetallic NPs are crucial for boosting nanomaterial based applications. Advanced synthetic protocols exist to make a large variety of such nanostructures. However, a major limiting factor for the usability of them in real life applications is their stability. Here, we show that Au/Pd octopods, 8-branched nanocrystals with Oh symmetry, with only a low amount of Pd exhibited a high thermal stability and maintained strong plasmon resonances up to 600 ◦C. Furthermore, we study the influence of the composition, morphology and environment on the thermal stability and define key parameters for the design of thermally stable multifunctional NPs. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000473248300038 | Publication Date | 2019-06-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 46 | Open Access | OpenAccess |
Notes | W. A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020. H. V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). E. B. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). J. D. S. and S.E.S acknowledge funding from the US National Science Foundation (award number: CHE-1602476). The authors acknowledge funding from the European Commission Grant (EUSMI E180600101 to S. B. and S. E. S.) and European Research Council (ERC Starting Grant #335078-COLOURATOMS). Realnano 815128; sygma | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:161356 | Serial | 5285 | ||
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Author | Skorikov, A.; Albrecht, W.; Bladt, E.; Xie, X.; van der Hoeven, J.E.S.; van Blaaderen, A.; Van Aert, S.; Bals, S. | ||||
Title | Quantitative 3D Characterization of Elemental Diffusion Dynamics in Individual Ag@Au Nanoparticles with Different Shapes | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 13 | Issue | 13 | Pages | 13421-13429 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Anisotropic bimetallic nanoparticles are promising candidates for plasmonic and catalytic applications. Their catalytic performance and plasmonic properties are closely linked to the distribution of the two metals, which can change during applications in which the particles are exposed to heat. Due to this fact, correlating the thermal stability of complex heterogeneous nanoparticles to their microstructural properties is of high interest for the practical applications of such materials. Here, we employ quantitative electron tomography in high-angle annular dark-field scanning transmission electron microscopy (HAADFSTEM) mode to measure the 3D elemental diffusion dynamics in individual anisotropic Au−Ag nanoparticles upon heating in situ. This approach allows us to study the elemental redistribution in complex, asymmetric nanoparticles on a single particle level, which has been inaccessible to other techniques so far. In this work, we apply the proposed method to compare the alloying dynamics of Au−Ag nanoparticles with different shapes and compositions and find that the shape of the nanoparticle does not exhibit a significant effect on the alloying speed whereas the composition does. Finally, comparing the experimental results to diffusion simulations allows us to estimate the diffusion coefficients of the metals for individual nanoparticles. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000500650000115 | Publication Date | 2019-10-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 29 | Open Access | OpenAccess |
Notes | This project has received funding from the European Commission (grant 731019, EUSMI) and European Research Council (ERC Consolidator Grants 815128, REALNANO; 770887, PICOMETRICS; 648991, 3MC; and ERC Advanced Grant 291667, HierarSACol). This project has also received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement 823717, ESTEEM3. W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 797153, SOPMEN). E.B. acknowledges a postdoctoral grant 12T2719N from the Research Foundation Flanders (FWO, Belgium). X.X. acknowledges financial support from the EU H2020-MSCAITN-2015 project 676045, MULTIMAT. The authors also acknowledge financial support by the Research Foundation Flanders (FWO grants G038116N, G026718N, and G036915N).; sygma; esteem3JRA; esteem3reported | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:164061 | Serial | 5379 | ||
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Author | Hinterding, S.O.M.; Berends, A.C.; Kurttepeli, M.; Moret, M.-E.; Meeldijk, J.D.; Bals, S.; van der Stam, W.; de Donega, C.M. | ||||
Title | Tailoring Cu+ for Ga3+ cation exchange in Cu2-xS and CuInS2 nanocrystals by controlling the Ga precursor chemistry | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 13 | Issue | 13 | Pages | 12880-12893 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanoscale cation exchange (CE) has resulted in colloidal nanomaterials that are unattainable by direct synthesis methods. Aliovalent CE is complex and synthetically challenging because the exchange of an unequal number of host and guest cations is required to maintain charge balance. An approach to control aliovalent CE reactions is the use of a single reactant to both supply the guest cation and extract the host cation. Here, we study the application of GaCl3-L complexes [L = trioctylphosphine (TOP), triphenylphosphite (TPP), diphenylphosphine (DPP)] as reactants in the exchange of Cu+ for Ga3+ in Cu2-xS nanocrystals. We find that noncomplexed GaCl3 etches the nanocrystals by S2- extraction, whereas GaCl3-TOP is unreactive. Successful exchange of Cu+ for Ga3+ is only possible when GaCl3 is complexed with either TPP or DPP. This is attributed to the pivotal role of the Cu2-xS-GaCl3-L activated complex that forms at the surface of the nanocrystal at the onset of the CE reaction, which must be such that simultaneous Ga3+ insertion and Cu+ extraction can occur. This requisite is only met if GaCl3 is bound to a phosphine ligand, with a moderate bond strength, to allow facile dissociation of the complex at the nanocrystal surface. The general validity of this mechanism is demonstrated by using GaCl3-DPP to convert CuInS2 into (Cu,Ga,In)S-2 nanocrystals, which increases the photoluminescence quantum yield 10 -fold, while blue -shifting the photoluminescence into the NIR biological window. This highlights the general applicability of the mechanistic insights provided by our work. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000500650000061 | Publication Date | 2019-10-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 27 | Open Access | OpenAccess |
Notes | ; S.O.M.H., W.v.d.S., A.C.B., and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under Grant Nos. ECHO.712.012.0001 and ECHO.712.014.001. S.B. acknowledges financial support from the European Research Council (ERC Consolidator Grant No. 815128-REALNANO). S.O.M.H. is supported by The Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation Programme funded by the Ministry of Education, Culture and Science of the government of The Netherlands. DFT calculations were carried out on the Dutch national e-infrastructure with the support of SURF Cooperative. This work was sponsored by NWO Physical Sciences for the use of supercomputer facilities. The authors thank Jessi van der Hoeven for EDS and TEM measurements. ; sygma | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:165149 | Serial | 6324 | ||
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Author | Rodal-Cedeira, S.; Vázquez-Arias, A.; Bodelon, G.; Skorikov, A.; Núñez-Sanchez, S.; La Porta, A.; Polavarapu, L.; Bals, S.; Liz-Marzán, L.M.; Perez-Juste, J.; Pastoriza-Santos, I. | ||||
Title | An Expanded Surface-Enhanced Raman Scattering Tags Library by Combinatorial Encapsulation of Reporter Molecules in Metal Nanoshells | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | Issue | Pages | |||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Raman-encoded gold nanoparticles have been widely employed as photostable multifunctional probes for sensing, bioimaging, multiplex diagnostics, and surface-enhanced Raman scattering (SERS)-guided tumor therapy. We report a strategy toward obtaining a particularly large library of Au nanocapsules encoded with Raman codes defined by the combination of different thiol-free Raman reporters, encapsulated at defined molar ratios. The fabrication of SERS tags with tailored size and pre-defined codes is based on the in situ incorporation of Raman reporter molecules inside Au nanocapsules during their formation via Galvanic replacement coupled to seeded growth on Ag NPs. The hole-free closed shell structure of the nanocapsules is confirmed by electron tomography. The unusually wide encoding possibilities of the obtained SERS tags are investigated by means of either wavenumber-based encoding or Raman frequency combined with signal intensity, leading to an outstanding performance as exemplified by 26 and 54 different codes, respectively. We additionally demonstrate that encoded nanocapsules can be readily bioconjugated with antibodies for applications such as SERS-based targeted cell imaging and phenotyping. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000595533800019 | Publication Date | 2020-09-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | 14 | Open Access | OpenAccess |
Notes | L.M.L.-M. acknowledges financial support from the European Research Council (ERC-AdG-4DbioSERS-787510) and the Spanish State Research Agency (Grant No. MDM-2017-0720 and PID2019-108954RB-I00). I.P.-S. and J.P.-J. acknowledge financial support from the Spanish State Research Agency (Grant No. MAT2016-77809-R)) and Ramon Areces Foundation (Grant No. SERSforSAFETY). G.B. acknowledges financial support from CINBIO (Grant number ED431G 2019/07 Xunta de Galicia). S.B. and A.S. acknowledge financial support by the Research Foundation Flanders (FWO grant G038116N). This project received funding as well from the European Union’s Horizon 2020 research and innovation program under grant agreement No 731019 (EUSMI). S.B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO). We thank Carlos Fernández-Lodeiro and Daniel García-Lojo for their helpful contribution to the SEM characterization and SERS analysis and Veronica Montes-García for her fruitful contribution in the PCA analysis.; sygma | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:172492 | Serial | 6403 | ||
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Author | Milagres de Oliveira, T.; Albrecht, W.; González-Rubio, G.; Altantzis, T.; Lobato Hoyos, I.P.; Béché, A.; Van Aert, S.; Guerrero-Martínez, A.; Liz-Marzán, L.M.; Bals, S. | ||||
Title | 3D Characterization and Plasmon Mapping of Gold Nanorods Welded by Femtosecond Laser Irradiation | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 14 | Issue | Pages | acsnano.0c02610 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Ultrafast laser irradiation can induce morphological and structural changes in plasmonic nanoparticles. Gold nanorods (Au NRs), in particular, can be welded together upon irradiation with femtosecond laser pulses, leading to dimers and trimers through the formation of necks between individual nanorods. We used electron tomography to determine the 3D (atomic) structure at such necks for representative welding geometries and to characterize the induced defects. The spatial distribution of localized surface plasmon modes for different welding configurations was assessed by electron energy loss spectroscopy. Additionally, we were able to directly compare the plasmon line width of single-crystalline and welded Au NRs with single defects at the same resonance energy, thus making a direct link between the structural and plasmonic properties. In this manner, we show that the occurrence of (single) defects results in significant plasmon broadening. | ||||
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Language | Wos | 000586793400016 | Publication Date | 2020-08-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | 25 | Open Access | OpenAccess |
Notes | This project has received funding from the European Research Council under the European Union's Horizon 2020 research and innovation program (ERC Consolidator Grants #815128 – REALNANO and #770887 – PICOMETRICS). The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project funding G.0381.16N and G.0267.18N. W.A. acknowledges an Individual Fellowship funded by the Marie 27 Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 797153, SOPMEN). G.G.-R. acknowledge receipt of FPI Fellowship from the Spanish MINECO. This work has been funded by the Spanish Ministry of Science, Innovation and Universities (MICIU) (Grants RTI2018-095844-B-I00 and MAT2017-86659-R) and the Madrid Regional Government (Grant P2018/NMT-4389). A.B. acknowledges funding from FWO project G093417N and from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. L.M.L.-M. acknowledges the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720); Comunidad de Madrid, P2018/NMT-4389 ; Ministerio de Ciencia, Innovación y Universidades, MAT2017-86659-R RTI2018-095844-B-I00 ; Ministerio de Economía y Competitividad; H2020 Marie Sklodowska-Curie Actions, 797153 ; Fonds Wetenschappelijk Onderzoek, G.0267.18N G.0381.16N G093417N ; H2020 Research Infrastructures, 823717 ; H2020 European Research Council, 770887 815128 ; Agencia Estatal de Investigación, Ministerio de Ciencia, Innovación y Universidades, MDM-2017-0720 ; sygma | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:172440 | Serial | 6426 | ||
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Author | Busatto, S.; Ruiter, M. de; Jastrzebski, J.T.B.H.; Albrecht, W.; Pinchetti, V.; Brovelli, S.; Bals, S.; Moret, M.-E.; de Mello Donega, C. | ||||
Title | Luminescent Colloidal InSb Quantum Dots from In Situ Generated Single-Source Precursor | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 14 | Issue | 10 | Pages | 13146-13160 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Despite recent advances, the synthesis of colloidal InSb quantum dots (QDs) remains underdeveloped, mostly due to the lack of suitable precursors. In this work, we use Lewis acid–base interactions between Sb(III) and In(III) species formed at room temperature in situ from commercially available compounds (viz., InCl3, Sb[NMe2]3 and a primary alkylamine) to obtain InSb adduct complexes. These complexes are successfully used as precursors for the synthesis of colloidal InSb QDs ranging from 2.8 to 18.2 nm in diameter by fast coreduction at sufficiently high temperatures (≥230 °C). Our findings allow us to propose a formation mechanism for the QDs synthesized in our work, which is based on a nonclassical nucleation event, followed by aggregative growth. This yields ensembles with multimodal size distributions, which can be fractionated in subensembles with relatively narrow polydispersity by postsynthetic size fractionation. InSb QDs with diameters below 7.0 nm have the zinc blende crystal structure, while ensembles of larger QDs (≥10 nm) consist of a mixture of wurtzite and zinc blende QDs. The QDs exhibit photoluminescence with small Stokes shifts and short radiative lifetimes, implying that the emission is due to band-edge recombination and that the direct nature of the bandgap of bulk InSb is preserved in InSb QDs. Finally, we constructed a sizing curve correlating the peak position of the lowest energy absorption transition with the QD diameters, which shows that the band gap of colloidal InSb QDs increases with size reduction following a 1/d dependence. | ||||
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Language | Wos | 000586793400068 | Publication Date | 2020-10-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | 21 | Open Access | OpenAccess |
Notes | S.B. and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under Grant No. TOP.715.016.001. W.A. acknowledges an Individual Fellowship from the Marie Sklodowska-Curie actions (MSCA) under the EU?s Horizon 2020 program (Grant No. 797153, SOPMEN). This project has received funding from the European Commission Grant (EUSMI E180900184) and European Research Council (ERC Consolidator Grant No. 815128 REALNANO).; sygma | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:173862 | Serial | 6438 | ||
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Author | Sun, C.; Liao, X.; Xia, F.; Zhao, Y.; Zhang, L.; Mu, S.; Shi, S.; Li, Y.; Peng, H.; Van Tendeloo, G.; Zhao, K.; Wu, J. | ||||
Title | High-voltage cycling induced thermal vulnerability in LiCoO₂ cathode : cation loss and oxygen release driven by oxygen vacancy migration | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 14 | Issue | 5 | Pages | 6181-6190 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The release of the lattice oxygen due to the thermal degradation of layered lithium transition metal oxides is one of the major safety concerns in Li-ion batteries. The oxygen release is generally attributed to the phase transitions from the layered structure to spinel and rocksalt structures that contain less lattice oxygen. Here, a different degradation pathway in LiCoO2 is found, through oxygen vacancy facilitated cation migration and reduction. This process leaves undercoordinated oxygen that gives rise to oxygen release while the structure integrity of the defect-free region is mostly preserved. This oxygen release mechanism can be called surface degradation due to the kinetic control of the cation migration but has a slow surface to bulk propagation with continuous loss of the surface cation ions. It is also strongly correlated with the high-voltage cycling defects that end up with a significant local oxygen release at low temperatures. This work unveils the thermal vulnerability of high-voltage Li-ion batteries and the critical role of the surface fraction as a general mitigating approach. | ||||
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Language | Wos | 000537682300101 | Publication Date | 2020-04-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | 8 | Open Access | Not_Open_Access |
Notes | ; C.S., X.L., and F.X. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (21905169). The S/TEM work was performed at the Nanostructure Research Center (NRC), which is supported by the Fundamental Research Funds for the Central Universities (WUT: 2019III012GX), the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, and the State Key Laboratory of Silicate Materials for Architectures (all of the laboratories are at Wuhan University of Technology). ; | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:170246 | Serial | 6537 | ||
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Author | Griffin, E.; Mogg, L.; Hao, G.-P.; Kalon, G.; Bacaksiz, C.; Lopez-Polin, G.; Zhou, T.Y.; Guarochico, V.; Cai, J.; Neumann, C.; Winter, A.; Mohn, M.; Lee, J.H.; Lin, J.; Kaiser, U.; Grigorieva, I., V; Suenaga, K.; Ozyilmaz, B.; Cheng, H.-M.; Ren, W.; Turchanin, A.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. | ||||
Title | Proton and Li-Ion permeation through graphene with eight-atom-ring defects | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 14 | Issue | 6 | Pages | 7280-7286 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Defect-free graphene is impermeable to gases and liquids but highly permeable to thermal protons. Atomic-scale defects such as vacancies, grain boundaries, and Stone-Wales defects are predicted to enhance graphene's proton permeability and may even allow small ions through, whereas larger species such as gas molecules should remain blocked. These expectations have so far remained untested in experiment. Here, we show that atomically thin carbon films with a high density of atomic-scale defects continue blocking all molecular transport, but their proton permeability becomes similar to 1000 times higher than that of defect-free graphene. Lithium ions can also permeate through such disordered graphene. The enhanced proton and ion permeability is attributed to a high density of eight-carbon-atom rings. The latter pose approximately twice lower energy barriers for incoming protons compared to that of the six-atom rings of graphene and a relatively low barrier of similar to 0.6 eV for Li ions. Our findings suggest that disordered graphene could be of interest as membranes and protective barriers in various Li-ion and hydrogen technologies. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000543744100086 | Publication Date | 2020-05-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | 53 | Open Access | |
Notes | ; The work was supported by the Lloyd's Register Foundation, EPSRC-EP/N010345/1, the European Research Council, the Graphene Flagship, the Deutsche Forschungsgemeinschaft project TRR 234 “CataLight” (Project B7, Grant No. 364549901), and the research infrastructure Grant No. INST 275/25 7-1 FUGG. E.G. and L.M. acknowledge the EPSRC NowNANO programme for funding. ; | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:170708 | Serial | 6586 | ||
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Author | Bagiński, M.; Pedrazo-Tardajos, A.; Altantzis, T.; Tupikowska, M.; Vetter, A.; Tomczyk, E.; Suryadharma, R.N.S.; Pawlak, M.; Andruszkiewicz, A.; Górecka, E.; Pociecha, D.; Rockstuhl, C.; Bals, S.; Lewandowski, W. | ||||
Title | Understanding and Controlling the Crystallization Process in Reconfigurable Plasmonic Superlattices | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | Issue | Pages | acsnano.0c09746 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | The crystallization of nanomaterials is a primary source of solid-state, photonic structures. Thus, a detailed understanding of this process is of paramount importance for the successful application of photonic nanomaterials in emerging optoelectronic technologies. While colloidal crystallization has been thoroughly studied, for example, with advanced in situ electron microscopy methods, the noncolloidal crystallization (freezing) of nanoparticles (NPs) remains so far unexplored. To fill this gap, in this work, we present proof-of principle experiments decoding a crystallization of reconfigurable assemblies of NPs at a solid state. The chosen material corresponds to an excellent testing bed, as it enables both in situ and ex situ investigation using X-ray diffraction (XRD), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), atomic force microscopy (AFM), and optical spectroscopy in visible and ultraviolet range (UV−vis) techniques. In particular, ensemble measurements with small-angle XRD highlighted the dependence of the correlation length in the NPs assemblies on the number of heating/cooling cycles and the rate of cooling. Ex situ TEM imaging further supported these results by revealing a dependence of domain size and structure on the sample preparation route and by showing we can control the domain size over 2 orders of magnitude. The application of HAADF-STEM tomography, combined with in situ thermal control, provided three-dimensional single-particle level information on the positional order evolution within assemblies. This combination of real and reciprocal space provides insightful information on the anisotropic, reversibly reconfigurable assemblies of NPs. TEM measurements also highlighted the importance of interfaces in the polydomain structure of nanoparticle solids, allowing us to understand experimentally observed differences in UV−vis extinction spectra of the differently prepared crystallites. Overall, the obtained results show that the combination of in situ heating HAADF-STEM tomography with XRD and ex situ TEM techniques is a powerful approach to study nanoparticle freezing processes and to reveal the crucial impact of disorder in the solid-state aggregates of NPs on their plasmonic properties. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000634569100101 | Publication Date | 2021-02-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 10 | Open Access | OpenAccess |
Notes | Ministerstwo Nauki i Szkolnictwa Wyzszego, 0112/DIA/2019/48 ; European Commission, 731019 E171000009 (EUSMI) ; Narodowe Centrum Nauki, 2016/21/N/ST5/03356 ; Deutsche Forschungsgemeinschaft, RO 3640/12-1 ; Fundacja na rzecz Nauki Polskiej, First TEAM2016–2/15 ; European Research Council, 815128 (REALNANO) ; sygma; | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:175872 | Serial | 6673 | ||
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Author | Frolov, A.S.; Sanchez-Barriga, J.; Callaert, C.; Hadermann, J.; Fedorov, A., V; Usachov, D.Y.; Chaika, A.N.; Walls, B.C.; Zhussupbekov, K.; Shvets, I., V.; Muntwiler, M.; Amati, M.; Gregoratti, L.; Varykhalov, A.Y.; Rader, O.; Yashina, L., V. | ||||
Title | Atomic and electronic structure of a multidomain GeTe crystal | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 14 | Issue | 12 | Pages | 16576-16589 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Renewed interest in the ferroelectric semi-conductor germanium telluride was recently triggered by the direct observation of a giant Rashba effect and a 30-year-old dream about a functional spin field-effect transistor. In this respect, all-electrical control of the spin texture in this material in combination with ferroelectric properties at the nanoscale would create advanced functionalities in spintronics and data information processing. Here, we investigate the atomic and electronic properties of GeTe bulk single crystals and their (111) surfaces. We succeeded in growing crystals possessing solely inversion domains of similar to 10 nm thickness parallel to each other. Using HAADF-TEM we observe two types of domain boundaries, one of them being similar in structure to the van der Waals gap in layered materials. This structure is responsible for the formation of surface domains with preferential Te-termination (similar to 68%) as we determined using photoelectron diffraction and XPS. The lateral dimensions of the surface domains are in the range of similar to 10-100 nm, and both Ge- and Te-terminations reveal no reconstruction. Using spin-ARPES we establish an intrinsic quantitative relationship between the spin polarization of pure bulk states and the relative contribution of different terminations, a result that is consistent with a reversal of the spin texture of the bulk Rashba bands for opposite configurations of the ferroelectric polarization within individual nanodomains. Our findings are important for potential applications of ferroelectric Rashba semiconductors in nonvolatile spintronic devices with advanced memory and computing capabilities at the nanoscale. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000603308800022 | Publication Date | 2020-11-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | |||
Call Number | UA @ admin @ c:irua:175027 | Serial | 6716 | ||
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Author | Walters, A.A.; Santacana-Font, G.; Li, J.; Routabi, N.; Qin, Y.; Claes, N.; Bals, S.; Tzu-Wen Wang, J.; Al-Jamal, K.T. | ||||
Title | Nanoparticle-MediatedIn SituMolecular Reprogramming of Immune Checkpoint Interactions for Cancer Immunotherapy | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 15 | Issue | 11 | Pages | 17549-17564 |
Keywords | A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Immune checkpoint blockade involves targeting immune regulatory molecules with antibodies. Preclinically, complex multiantibody regimes of both inhibitory and stimulatory targets are a promising candidate for the next generation of immunotherapy. However, in this setting, the antibody platform may be limited due to excessive toxicity caused by off target effects as a result of systemic administration. RNA can be used as an alternate to antibodies as it can both downregulate immunosuppressive checkpoints (siRNA) or induce expression of immunostimulatory checkpoints (mRNA). In this study, we demonstrate that the combination of both siRNA and mRNA in a single formulation can simultaneously knockdown and induce expression of immune checkpoint targets, thereby reprogramming the tumor microenvironment from immunosuppressive to immunostimulatory phenotype. To achieve this, RNA constructs were synthesized and formulated into stable nucleic acid lipid nanoparticles (SNALPs); the SNALPs produced were 140−150 nm in size with >80% loading efficiency. SNALPs could transfect macrophages and B16F10 cells in vitro resulting in 75% knockdown of inhibitory checkpoint (PDL1) expression and simultaneously express high levels of stimulatory checkpoint (OX40L) with minimal toxicity. Intratumoral treatment with the proposed formulation resulted in statistically reduced tumor growth, a greater density of CD4+ and CD8+ infiltrates in the tumor, and immune activation within tumor-draining lymph nodes. These data suggest that a single RNA-based formulation can successfully reprogram multiple immune checkpoint interactions on a cellular level. Such a candidate may be able to replace future immune checkpoint therapeutic regimes composed of both stimulatory- and inhibitory-receptor-targeting antibodies. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000747115200039 | Publication Date | 2021-11-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 11 | Open Access | OpenAccess |
Notes | A.A.W. is the grateful recipient of a Maplethorpe Fellowship. K.A.J. acknowledges funding from the British Council (Newton Fund, 337313), Wellcome Trust (WT103913), and the Cancer Research UK King’s Health Partners Centre at King’s College London. Financial support is acknowledged from the European Commission under the Horizon 2020 Programme, by means of Grant Agreement No. 731019 (EUSMI). Images were drawn on BioRender.com. | Approved | Most recent IF: 13.942 | ||
Call Number | EMAT @ emat @c:irua:183950 | Serial | 6829 | ||
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Author | Choukroun, D.; Pacquets, L.; Li, C.; Hoekx, S.; Arnouts, S.; Baert, K.; Hauffman, T.; Bals, S.; Breugelmans, T. | ||||
Title | Mapping composition–selectivity relationships of supported sub-10 nm Cu–Ag nanocrystals for high-rate CO₂ electroreduction | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 15 | Issue | 9 | Pages | 14858-14872 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Colloidal Cu–Ag nanocrystals measuring less than 10 nm across are promising candidates for integration in hybrid CO2 reduction reaction (CO2RR) interfaces, especially in the context of tandem catalysis and selective multicarbon (C2–C3) product formation. In this work, we vary the synthetic-ligand/copper molar ratio from 0.1 to 1.0 and the silver/copper atomic ratio from 0 to 0.7 and study the variations in the nanocrystals’ size distribution, morphology and reactivity at rates of ≥100 mA cm–2 in a gas-fed recycle electrolyzer operating under neutral to mildly basic conditions (0.1–1.0 M KHCO3). High-resolution electron microscopy and spectroscopy are used in order to characterize the morphology of sub-10 nm Cu–Ag nanodimers and core–shells and to elucidate trends in Ag coverage and surface composition. It is shown that Cu–Ag nanocrystals can be densely dispersed onto a carbon black support without the need for immediate ligand removal or binder addition, which considerably facilitates their application. Although CO2RR product distribution remains an intricate function of time, (kinetic) overpotential and processing conditions, we nevertheless conclude that the ratio of oxygenates to hydrocarbons (which depends primarily on the initial dispersion of the nanocrystals and their composition) rises 3-fold at moderate Ag atom % relative to Cu NCs-based electrodes. Finally, the merits of this particular Cu–Ag/C system and the recycling reactor employed are utilized to obtain maximum C2–C3 partial current densities of 92–140 mA cm–2 at −1.15 VRHE and liquid product concentrations in excess of 0.05 wt % in 1 M KHCO3 after short electrolysis periods. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000703553600082 | Publication Date | 2021-08-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 25 | Open Access | OpenAccess |
Notes | D.C. acknowledges Thomas Kenis for configuring the analytical instrumentation (HPLC/GC-FID/ICP-MS), Hannelore Andries for assistance with ICP-MS measurements, and Dr. Saeid Pourbabak and Dr. Tine Derez for assistance with Cu sputtering. L.P. was supported by Research Foundation of Flanders (FWO 1S56920N). S.B. acknowledges financial support from ERC Consolidator grant number 815128 REALNANO. S.B. and T.B. acknowledge financial support from the university research fund (BOF-GOA-PS ID no. 33928).; sygmaSB | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:180305 | Serial | 6844 | ||
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Author | Dey, A.; Ye, J.; De, A.; Debroye, E.; Ha, S.K.; Bladt, E.; Kshirsagar, A.S.; Wang, Z.; Yin, J.; Wang, Y.; Quan, L.N.; Yan, F.; Gao, M.; Li, X.; Shamsi, J.; Debnath, T.; Cao, M.; Scheel, M.A.; Kumar, S.; Steele, J.A.; Gerhard, M.; Chouhan, L.; Xu, K.; Wu, X.-gang; Li, Y.; Zhang, Y.; Dutta, A.; Han, C.; Vincon, I.; Rogach, A.L.; Nag, A.; Samanta, A.; Korgel, B.A.; Shih, C.-J.; Gamelin, D.R.; Son, D.H.; Zeng, H.; Zhong, H.; Sun, H.; Demir, H.V.; Scheblykin, I.G.; Mora-Sero, I.; Stolarczyk, J.K.; Zhang, J.Z.; Feldmann, J.; Hofkens, J.; Luther, J.M.; Perez-Prieto, J.; Li, L.; Manna, L.; Bodnarchuk, M., I; Kovalenko, M., V; Roeffaers, M.B.J.; Pradhan, N.; Mohammed, O.F.; Bakr, O.M.; Yang, P.; Muller-Buschbaum, P.; Kamat, P., V; Bao, Q.; Zhang, Q.; Krahne, R.; Galian, R.E.; Stranks, S.D.; Bals, S.; Biju, V.; Tisdale, W.A.; Yan, Y.; Hoye, R.L.Z.; Polavarapu, L. | ||||
Title | State of the art and prospects for Halide Perovskite Nanocrystals | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 15 | Issue | 7 | Pages | 10775-10981 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Metal-halide perovskites have rapidly emerged as one of the most promising materials of the 21st century, with many exciting properties and great potential for a broad range of applications, from photovoltaics to optoelectronics and photocatalysis. The ease with which metal-halide perovskites can be synthesized in the form of brightly luminescent colloidal nanocrystals, as well as their tunable and intriguing optical and electronic properties, has attracted researchers from different disciplines of science and technology. In the last few years, there has been a significant progress in the shape-controlled synthesis of perovskite nanocrystals and understanding of their properties and applications. In this comprehensive review, researchers having expertise in different fields (chemistry, physics, and device engineering) of metal-halide perovskite nanocrystals have joined together to provide a state of the art overview and future prospects of metal-halide perovskite nanocrystal research. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000679406500006 | Publication Date | 2021-06-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 538 | Open Access | OpenAccess |
Notes | E.D. and J.H. acknowledge financial support from the Research FoundationFlanders (FWO Grant Nos. S002019N, G.0B39.15, G.0B49.15, G.0962.13, G098319N, and ZW15_09-GOH6316), the Research Foundation Flanders postdoctoral fellowships to J.A.S. and E.D. (FWO Grant Nos. 12Y7218N and 12O3719N, respectively), | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:180553 | Serial | 6846 | ||
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