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Records |
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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. |
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Title |
Annealing-Induced Bi Bilayer on Bi2Te3 Investigated via Quasi-Particle-Interference Mapping |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
10 |
Issue |
10 |
Pages |
8778-8787 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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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. |
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Address |
Department of Physics, Virginia Tech , Blacksburg, Virginia 24061, United States |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000384399300073 |
Publication Date |
2016-09-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
15 |
Open Access |
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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 |
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Call Number |
EMAT @ emat @ c:irua:136269 |
Serial |
4294 |
Permanent link to this record |
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Author |
Lentijo-Mozo, S.; Tan, R.P.; Garcia-Marcelot, C.; Altantzis, T.; Fazzini, P.F.; Hungria, T.; Cormary, B.; Gallagher, J.R.; Miller, J.T.; Martinez, H.; Schrittwieser, S.; Schotter, J.; Respaud, M.; Bals, S.; Van Tendeloo, G.; Gatel, C.; Soulantica, K. |
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Title |
Air- and water-resistant noble metal coated ferromagnetic cobalt nanorods |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
2792-2804 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Cobalt nanorods possess ideal magnetic properties for applications requiring magnetically hard nanoparticles. However, their exploitation is undermined by their sensitivity toward oxygen and water, which deteriorates their magnetic properties. The development of a continuous metal shell inert to oxidation could render them stable, opening perspectives not only for already identified applications but also for uses in which contact with air and/or aqueous media is inevitable. However, the direct growth of a conformal noble metal shell on magnetic metals is a challenge. Here, we show that prior treatment of Co nanorods with a tin coordination compound is the crucial step that enables the subsequent growth of a continuous noble metal shell on their surface, rendering them air- and water-resistant, while conserving the monocrystallity, metallicity and the magnetic properties of the Co core. Thus, the as-synthesized coreshell ferromagnetic nanorods combine high magnetization and strong uniaxial magnetic anisotropy, even after exposure to air and water, and hold promise for successful implementation in in vitro biodiagnostics requiring probes of high magnetization and anisotropic shape. |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Wos |
000351791800055 |
Publication Date |
2015-03-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
25 |
Open Access |
OpenAccess |
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Notes |
312483 Esteem2; 246791 Countatoms; 335078 Colouratom; esteem2ta; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:125380 c:irua:125380 |
Serial |
87 |
Permanent link to this record |
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Author |
Javon, E.; Gaceur, M.; Dachraoui, W.; Margeat, O.; Ackermann, J.; Ilenia Saba, M.; Delugas, P.; Mattoni, A.; Bals, S.; Van Tendeloo, G. |
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Title |
Competing forces in the self-assembly of coupled ZnO nanopyramids |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
3685-3694 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Self-assembly (SA) of nanostructures has recently gained increasing interest. A clear understanding of the process is not straightforward since SA of nanoparticles is a complex multiscale phenomenon including different driving forces. Here, we study the SA between aluminum doped ZnO nanopyramids into couples by combining inorganic chemistry and advanced electron microscopy techniques with atomistic simulations. Our results show that the SA of the coupled nanopyramids is controlled first by morphology, as coupling only occurs in the case of pyramids with well-developed facets of the basal planes. The combination of electron microscopy and atomistic modeling reveals that the coupling is further driven by strong ligandligand interaction between the bases of the pyramids as dominant force, while screening effects due to Al doping or solvent as well as corecore interaction are only minor contributions. Our combined approach provides a deeper understanding of the complex interplay between the interactions at work in the coupled SA of ZnO nanopyramids. |
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Thesis |
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Place of Publication |
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Editor |
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Wos |
000353867000030 |
Publication Date |
2015-03-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
21 |
Open Access |
OpenAccess |
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Notes |
Esmi; 335078 Colouratom; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:125978 |
Serial |
434 |
Permanent link to this record |
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Author |
Chen, B.; Sahin, H.; Suslu, A.; Ding, L.; Bertoni, M.I.; Peeters, F.M.; Tongay, S. |
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Title |
Environmental changes in MoTe2 excitonic dynamics by defects-activated molecular interaction |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
5326-5332 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Monolayers of group VI transition metal dichalcogenides possess direct gaps in the visible spectrum with the exception of MoTe2, where its gap is suitably located in the infrared region but its stability is of particular interest, as tellurium compounds are acutely sensitive to oxygen exposure. Here, our environmental (time-dependent) measurements reveal two distinct effects on MoTe2 monolayers: For weakly luminescent monolayers, photoluminescence signal and optical contrast disappear, as if they are decomposed, but yet remain intact as evidenced by AFM and Raman measurements. In contrast, strongly luminescent monolayers retain their optical contrast for a prolonged amount of time, while their PL peak blue-shifts and PL intensity saturates to slightly lower values. Our X-ray photoelectron spectroscopy measurements and DFT calculations suggest that the presence of defects and functionalization of these defect sites with O-2 molecules strongly dictate their material properties and aging response by changing the excitonic dynamics due to deep or shallow states that are created within the optical band gap. Presented results not only shed light on environmental effects on fundamental material properties and excitonic dynamics of MoTe2 monolayers but also highlight striking material transformation for metastable 20 systems such as WTe2, silicone, and phosphorene. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000355383000068 |
Publication Date |
2015-04-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
150 |
Open Access |
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Notes |
; This work was supported by the Arizona State University seeding program. The authors thank Hui Cai and Kedi Wu for useful discussions. We gratefully acknowledge the use of facilities at the LeRoy Eyring Center for Solid State Science at Arizona State University. This work was supported by the Flemish Science Foundation (FWO-VI) and the Methusalem Foundation of the Flemish government. H.S. is supported by a FWO Pegasus Long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:126441 |
Serial |
1068 |
Permanent link to this record |
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Author |
Sanz-Ortiz, M.N.; Sentosun, K.; Bals, S.; Liz-Marzan, L.M. |
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Title |
Templated Growth of Surface Enhanced Raman Scattering -Active Branched Au Nanoparticles within Radial Mesoporous Silica Shells |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
10489-10497 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Noble metal nanoparticles are widely used as probes or substrates for surface-enhanced Raman scattering (SERS), due to their characteristic plasmon resonances in the visible and NIR spectral ranges. Aiming at obtaining a versatile system with high SERS performance we developed the synthesis of quasi-monodisperse, non-aggregated gold nanoparticles protected by radial mesoporous silica shells. The radial channels of such shells were used as templates for the growth of gold tips branching from the cores, thereby improving the plasmonic performance of the particles while favoring the localization of analyte molecules at high electric field regions: close to the tips, inside the pores. The method, which allows control over tip length, was successfully applied to various gold nanoparticle shapes, leading to materials with highly efficient SERS performance. The obtained nanoparticles are stable in ethanol and water upon thermal consolidation and can be safely stored as a powder. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000363915300105 |
Publication Date |
2015-09-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
110 |
Open Access |
OpenAccess |
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Notes |
This work has been funded by the European Research Council (ERC Advanced Grant 267867 Plasmaquo and Starting Grant Colouratom). The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013 under grant agreement no. 312184, SACS). Help from Mert Kurttepeli is acknowledged. Pentatwinned nanorods and nanotriangles were synthesized by L. Scarabelli.; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:129194 |
Serial |
3947 |
Permanent link to this record |
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Author |
Yan, Y.; Zhou, X.; Jin, H.; Li, C.-Z.; Ke, X.; Van Tendeloo, G.; Liu, K.; Yu, D.; Dressel, M.; Liao, Z.-M. |
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Title |
Surface-Facet-Dependent Phonon Deformation Potential in Individual Strained Topological Insulator Bi2Se3 Nanoribbons |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
10244-10251 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Strain is an important method to tune the properties of topological insulators. For example, compressive strain can induce superconductivity in Bi2Se3 bulk material. Topological insulator nanostructures are the superior candidates to utilize the unique surface states due to the large surface to volume ratio. Therefore, it is highly desirable to monitor the local strain effects in individual topological insulator nanostructures. Here, we report the systematical micro-Raman spectra of single strained Bi2Se3 nanoribbons with different thicknesses and different surface facets, where four optical modes are resolved in both Stokes and anti-Stokes Raman spectral lines. A striking anisotropy of the strain dependence is observed in the phonon frequency of strained Bi2Se3 nanoribbons grown along the ⟨112̅0⟩ direction. The frequencies of the in-plane Eg2 and out-of-plane A1g1 modes exhibit a nearly linear blue-shift against bending strain when the nanoribbon is bent along the ⟨112̅0⟩ direction with the curved {0001} surface. In this case, the phonon deformation potential of the Eg2 phonon for 100 nm-thick Bi2Se3 nanoribbon is up to 0.94 cm–1/%, which is twice of that in Bi2Se3 bulk material (0.52 cm–1/%). Our results may be valuable for the strain modulation of individual topological insulator nanostructures. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000363915300079 |
Publication Date |
2015-09-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
14 |
Open Access |
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Notes |
Y.Y. would like to thank Xuewen Fu for helpful discussions. This work was supported by MOST (Nos. 2013CB934600, 2013CB932602) and NSFC (Nos. 11274014, 11234001). |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:129216 |
Serial |
3963 |
Permanent link to this record |
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Author |
Chen, J.J.; Wang, Q.; Meng, J.; Ke, X.; Van Tendeloo, G.; Bie, Y.Q.; Liu, J.; Liu, K.; Liao, Z.M.; Sun, D.; Yu, D.; |
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Title |
Photovoltaic effect and evidence of carrier multiplication in graphene vertical homojunctions with asymmetrical metal contacts |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
8851-8858 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Graphene exhibits exciting potentials for high-speed wideband photodetection and high quantum efficiency solar energy harvest because of its broad spectral absorption, fast photoelectric response, and potential carrier multiplication. Although photocurrent can be generated near a metalgraphene interface in lateral devices, the photoactive area is usually limited to a tiny one-dimensional line-like interface region. Here, we report photoelectric devices based on vertical graphene two-dimensional homojunction, which is fabricated via vertically stacking four graphene monolayers with asymmetric metal contacts. The devices show excellent photovoltaic output with excitation wavelength ranging from visible light to mid-infrared. The wavelength dependence of the internal quantum efficiency gives direct evidence of the carrier multiplication effect in graphene. The simple fabrication process, easy scale-up, large photoresponsive active area, and broadband response of the vertical graphene device are very promising for practical applications in optoelectronics and photovoltaics. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000361935800023 |
Publication Date |
2015-08-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
11 |
Open Access |
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Notes |
246791 Countatoms |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:127689 |
Serial |
2615 |
Permanent link to this record |
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Author |
Ghosh, S.; Gaspari, R.; Bertoni, G.; Spadaro, M.C.; Prato, M.; Turner, S.; Cavalli, A.; Manna, L.; Brescia, R. |
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Title |
Pyramid-Shaped Wurtzite CdSe Nanocrystals with Inverted Polarity |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
8537-8546 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on pyramid-shaped wurtzite cadmium selenide (CdSe) nanocrystals (NCs), synthesized by hot injection in the presence of chloride ions as shape-directing agents, exhibiting reversed crystal polarity compared to former reports. Advanced transmission electron microscopy (TEM) techniques (image-corrected high-resolution TEM with exit wave reconstruction and probe-corrected high-angle annular dark field-scanning TEM) unequivocally indicate that the triangular base of the pyramids is the polar (0001) facet and their apex points toward the [0001] direction. Density functional theory calculations, based on a simple model of binding of Cl(-) ions to surface Cd atoms, support the experimentally evident higher thermodynamic stability of the (0001) facet over the (0001) one conferred by Cl(-) ions. The relative stability of the two polar facets of wurtzite CdSe is reversed compared to previous experimental and computational studies on Cd chalcogenide NCs, in which no Cl-based chemicals were deliberately used in the synthesis or no Cl(-) ions were considered in the binding models. Self-assembly of these pyramids in a peculiar clover-like geometry, triggered by the addition of oleic acid, suggests that the basal (polar) facet has a density and perhaps type of ligands significantly different from the other three facets, since the pyramids interact with each other exclusively via their lateral facets. A superstructure, however with no long-range order, is observed for clovers with their (0001) facets roughly facing each other. The CdSe pyramids were also exploited as seeds for CdS pods growth, and the peculiar shape of the derived branched nanostructures clearly arises from the inverted polarity of the seeds. |
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Address |
Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego 30, I-16163 Genova, Italy |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000360323300085 |
Publication Date |
2015-07-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
16 |
Open Access |
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Notes |
PMID:26203791 |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:127807 |
Serial |
3956 |
Permanent link to this record |
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Author |
van der Stam, W.; Bladt, E.; Rabouw, F.T.; Bals, S.; de Mello Donega, C. |
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Title |
Near-Infrared Emitting CuInSe/CuInS Dot Core/Rod Shell Heteronanorods by Sequential Cation Exchange |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
9 |
Issue |
9 |
Pages |
11430-11438 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The direct synthesis of heteronanocrystals (HNCs) combining different ternary semiconductors is challenging and has not yet been successful. Here, we report a sequential topotactic cation exchange (CE) pathway that yields CuInSe2/CuInS2 dot core/rod shell nanorods with near-infrared luminescence. In our approach, the Cu+ extraction rate is coupled to the In3+ incorporation rate by the use of a stoichiometric trioctylphosphine-InCl3 complex, which fulfills the roles of both In-source and Cu-extracting agent. In this way, Cu+ ions can be extracted by trioctylphosphine ligands only when the In-P bond is broken. This results in readily available In3+ ions at the same surface site from which the Cu+ is extracted, making the process a direct place exchange reaction and shifting the overall energy balance in favor of the CE. Consequently, controlled cation exchange can occur even in large and anisotropic heterostructured nanocrystals with preservation of the size, shape, and heterostructuring of the template NCs into the product NCs. The cation exchange is self-limited, stopping when the ternary core/shell CuInSe2/CuInS2 composition is reached. The method is very versatile, successfully yielding a variety of luminescent CuInX2 (X = S, Se, and Te) quantum dots, nanorods, and HNCs, by using Cd-chalcogenide NCs and HNCs as templates. The approach reported here thus opens up routes toward materials with unprecedented properties, which would otherwise remain inaccessible. |
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Address |
Debye Institute for Nanomaterials Science, Utrecht University , P.O. Box 80000, 3508 TA Utrecht, The Netherlands |
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Corporate Author |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000365464800094 |
Publication Date |
2015-10-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
88 |
Open Access |
OpenAccess |
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Notes |
The authors thank Gang Wang for XRD measurements and Eline Hutter for providing CdSe/CdS NRs. W.v.d.S. 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 number ECHO.712.012.001. This work was supported by the European Research Council (ERC Starting Grant #335078 Colouratom). E.B. gratefully acknowledges financial support by the Flemish Fund for Scientific Research (FWO Vlaanderen).; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:129184 |
Serial |
3948 |
Permanent link to this record |
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Author |
Kundu, P.; Turner, S.; Van Aert, S.; Ravishankar, N.; Van Tendeloo, G. |
|
Title |
Atomic structure of quantum gold nanowires : quantification of the lattice strain |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
1 |
Pages |
599-606 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Theoretical studies exist to compute the atomic arrangement in gold nanowires and the influence on their electronic behavior with decreasing diameter. Experimental studies, e.g., by transmission electron microscopy, on chemically synthesized ultrafine wires are however lacking owing to the unavailability of suitable protocols for sample preparation and the stability of the wires under electron beam irradiation. In this work, we present an atomic scale structural investigation on quantum single crystalline gold nanowires of 2 nm diameter, chemically prepared on a carbon film grid. Using low dose aberration-corrected high resolution (S)TEM, we observe an inhomogeneous strain distribution in the crystal, largely concentrated at the twin boundaries and the surface along with the presence of facets and surface steps leading to a noncircular cross section of the wires. These structural aspects are critical inputs needed to determine their unique electronic character and their potential as a suitable catalyst material. Furthermore, electron-beam-induced structural changes at the atomic scale, having implications on their mechanical behavior and their suitability as interconnects, are discussed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000330542900061 |
Publication Date |
2013-11-29 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
20 |
Open Access |
|
|
Notes |
FWO; Countatoms; Hercules |
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:113856 |
Serial |
199 |
Permanent link to this record |
|
|
|
|
Author |
Xu, X.; Vereecke, G.; Chen, C.; Pourtois, G.; Armini, S.; Verellen, N.; Tsai, W.K.; Kim, D.W.; Lee, E.; Lin, C.Y.; Van Dorpe, P.; Struyf, H.; Holsteyns, F.; Moshchalkov, V.; Indekeu, J.; De Gendt, S.; |
|
Title |
Capturing wetting states in nanopatterned silicon |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
1 |
Pages |
885-893 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
Abstract |
Spectacular progress in developing advanced Si circuits with reduced size, along the track of Moore's law, has been relying on necessary developments in wet cleaning of nanopatterned Si wafers to provide contaminant free surfaces. The most efficient cleaning is achieved when complete wetting can be realized. In this work, ordered arrays of silicon nanopillars on a hitherto unexplored small scale have been used to study the wetting behavior on nanomodulated surfaces in a substantial range of surface treatments and geometrical parameters. With the use of optical reflectance measurements, the nanoscale water imbibition depths have been measured and the transition to the superhydrophobic Cassie-Baxter state has been accurately determined. For pillars of high aspect ratio (about 15), the transition occurs even when the surface is grafted with a hydrophilic functional group. We have found a striking consistent deviation between the contact angle measurements and the straightforward application of the classical wetting models. Molecular dynamics simulations show that these deviations can be attributed to the long overlooked atomic-scale surface perturbations that are introduced during the nanofabrication process. When the transition condition is approached, transient states of partial imbibition that characterize intermediate states between the Wenzel and Cassie-Baxter states are revealed in our experiments. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000330542900092 |
Publication Date |
2013-12-31 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
39 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:114871 |
Serial |
276 |
Permanent link to this record |
|
|
|
|
Author |
Walter, A.L.; Sahin, H.; Jeon, K.J.; Bostwick, A.; Horzum, S.; Koch, R.; Speck, F.; Ostler, M.; Nagel, P.; Merz, M.; Schupler, S.; Moreschini, L.; Chang, Y.J.; Seyller, T.; Peeters, F.M.; Horn, K.; Rotenberg, E.; |
|
Title |
Luminescence, patterned metallic regions, and photon-mediated electronic changes in single-sided fluorinated graphene sheets |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
8 |
Pages |
7801-7808 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
Abstract |
Single-sided fluorination has been predicted to open an electronic band gap in graphene and to exhibit unique electronic and magnetic properties; however, this has not been substantiated by experimental reports. Our comprehensive experimental and theoretical study of this material on a SiC(0001) substrate shows that single-sided fluorographene exhibits two phases, a stable one with a band gap of similar to 6 eV and a metastable one, induced by UV irradiation, with a band gap of similar to 2.5 eV. The metastable structure, which reverts to the stable “ground-state” phase upon annealing under emission of blue light, in our view is induced by defect states, based on the observation of a nondispersive electronic state at the top of the valence band, not unlike that found in organic molecular layers. Our structural data show that the stable C2F ground state has a “boat” structure, in agreement with our X-ray magnetic circular dichroism data, which show the absence of an ordered magnetic phase. A high flux of UV or X-ray photons removes the fluorine atoms, demonstrating the possibility of lithographically patterning conducting regions into an otherwise semiconducting 2D material. |
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Address |
|
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
|
|
Language |
|
Wos |
000340992300025 |
Publication Date |
2014-08-09 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
23 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:119263 |
Serial |
1857 |
Permanent link to this record |
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|
|
|
Author |
El-Gogary, R.I.; Rubio, N.; Wang, J.T.W.; Al-Jamal, W.T.; Bourgognon, M.; Kafa, H.; Naeem, M.; Klippstein, R.; Abbate, V.; Leroux, F.; Bals, S.; Van Tendeloo, G.; Kamel, A.O.; Awad, G.A.S.; Mortada, N.D.; Al-Jamal, K.T.; |
|
Title |
Polyethylene glycol conjugated polymeric nanocapsules for targeted delivery of quercetin to folate-expressing cancer cells in vitro and in vivo |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
2 |
Pages |
1384-1401 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
In this work we describe the formulation and characterization of chemically modified polymeric nanocapsules incorporating the anticancer drug, quercetin, for the passive and active targeting to tumors. Folic acid was conjugated to poly(lactide-co-glycolide) (PLGA) polymer to facilitate active targeting to cancer cells. Two different methods for the conjugation of PLGA to folic acid were employed utilizing polyethylene glycol (PEG) as a spacer. Characterization of the conjugates was performed using FTIR and H-1 NMR studies. The PEG and folk acid content was independent of the conjugation methodology employed. PEGylation has shown to reduce the size of the nanocapsule; moreover, zeta-potential was shown to be polymer-type dependent. Comparative studies on the cytotoxicity and cellular uptake of the different formulations by He La cells, in the presence and absence of excess folic acid, were carried out using MTT assay and Confocal Laser Scanning Microscopy, respectively. Both results confirmed the selective uptake and cytotoxicity of the folic acid targeted nanocapsules to the folate enriched cancer cells in a folate-dependent manner. Finally, the passive tumor accumulation and the active targeting of the nanocapsules to folate-expressing cells were confirmed upon intravenous administration in He La or IGROV-1 tumor-bearing mice. The developed nanocapsules provide a system for targeted delivery of a range of hydrophobic anticancer drugs in vivo. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000332059200032 |
Publication Date |
2014-01-07 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
144 |
Open Access |
Not_Open_Access |
|
Notes |
290023 Raddel; 262348 Esmi; Iap-Pai |
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:115862 |
Serial |
2670 |
Permanent link to this record |
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|
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Author |
Galván-Moya, J.E.; Altantzis, T.; Nelissen, K.; Peeters, F.M.; Grzelczak, M.; Liz-Marán, L.M.; Bals, S.; Van Tendeloo, G. |
|
Title |
Self-organization of highly symmetric nanoassemblies : a matter of competition |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
4 |
Pages |
3869-3875 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
The properties and applications of metallic nanoparticles are inseparably connected not only to their detailed morphology and composition but also to their structural configuration and mutual interactions. As a result, the assemblies often have superior properties as compared to individual nanoparticles. Although it has been reported that nanoparticles can form highly symmetric clusters, if the configuration can be predicted as a function of the synthesis parameters, more targeted and accurate synthesis will be possible. We present here a theoretical model that accurately predicts the structure and configuration of self-assembled gold nanoclusters. The validity of the model is verified using quantitative experimental data extracted from electron tomography 3D reconstructions of different assemblies. The present theoretical model is generic and can in principle be used for different types of nanoparticles, providing a very wide window of potential applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000334990600084 |
Publication Date |
2014-03-13 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
34 |
Open Access |
OpenAccess |
|
Notes |
FWO; Methusalem; 246791 COUNTATOMS; 335078 COLOURATOM; 262348 ESMI; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:116955 |
Serial |
2977 |
Permanent link to this record |
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|
Author |
Xu, P.; Dong, L.; Neek-Amal, M.; Ackerman, M.L.; Yu, J.; Barber, S.D.; Schoelz, J.K.; Qi, D.; Xu, F.; Thibado, P.M.; Peeters, F.M.; |
|
Title |
Self-organized platinum nanoparticles on freestanding graphene |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
3 |
Pages |
2697-2703 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
Abstract |
Freestanding graphene membranes were successfully functionalized with platinum nanoparticles (Pt NPs). High-resolution transmission electron microscopy revealed a homogeneous distribution of single-crystal Pt NPs that tend to exhibit a preferred orientation. Unexpectedly, the NPs were also found to be partially exposed to the vacuum with the top Pt surface raised above the graphene substrate, as deduced from atomic-scale scanning tunneling microscopy images and detailed molecular dynamics simulations. Local strain accumulation during the growth process is thought to be the origin of the NP self-organization. These findings are expected to shape future approaches in developing Pt NP catalysts for fuel cells as well as NP-functionalized graphene-based high-performance electronics. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000333539400085 |
Publication Date |
2014-02-05 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
38 |
Open Access |
|
|
Notes |
; M.N.A. acknowledges financial support by the EU-Marie Curie IIF postdoc Fellowship/299855. F.M.P. acknowledges financial support by the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Foundation of the Flemish Government. L.D. acknowledges financial support by the Taishan Overseas Scholar program (tshw20091005), the International Science & Technology Cooperation Program of China (2014DFA60150), the National Natural Science Foundation of China (51172113), the Shandong Natural Science Foundation (JQ201118), the Qingdao Municipal Science and Technology Commission (12-1-4-136-hz), and the National Science Foundation (DMR-0821159). P.M.T. is thankful for the financial support of the Office of Naval Research under Grant No. N00014-10-1-0181 and the National Science Foundation under Grant No. DMR-0855358. ; |
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:116881 |
Serial |
2978 |
Permanent link to this record |
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Author |
Goris, B.; Turner, S.; Bals, S.; Van Tendeloo, G. |
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Title |
Three-dimensional valency mapping in ceria nanocrystals |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
10 |
Pages |
10878-10884 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Using electron tomography combined with electron energy loss spectroscopy (EELS), we are able to map the valency of the Ce ions in CeO2-x nanocrystals in three dimensions. Our results show a clear facet-dependent reduction shell at the surface of ceria nanoparticles; {111} surface facets show a low surface reduction, whereas at {001} surface facets, the cerium ions are more likely to be reduced over a larger surface shell. Our generic tomographic technique allows a full 3D data cube to be reconstructed, containing an EELS spectrum in each voxel. This possibility enables a three-dimensional investigation of a plethora of material-specific physical properties such as valency, chemical composition, oxygen coordination, or bond lengths, triggering the synthesis of nanomaterials with improved properties. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000343952600126 |
Publication Date |
2014-10-06 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
85 |
Open Access |
OpenAccess |
|
Notes |
335078 Colouratom; 246791 Countatoms; Fwo; 312483 Esteem2; esteem2jra4; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:121219 |
Serial |
3656 |
Permanent link to this record |
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Author |
Heyer, S.; Janssen, W.; Turner, S.; Lu, Y.-G.; Yeap, W.S.; Verbeeck, J.; Haenen, K.; Krueger, A. |
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Title |
Toward deep blue nano hope diamonds : heavily boron-doped diamond nanoparticles |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
8 |
Issue |
6 |
Pages |
5757-5764 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
The production of boron-doped diamond nanoparticles enables the application of this material for a broad range of fields, such as electrochemistry, thermal management, and fundamental superconductivity research. Here we present the production of highly boron-doped diamond nanoparticles using boron-doped CVD diamond films as a starting material. In a multistep milling process followed by purification and surface oxidation we obtained diamond nanoparticles of 1060 nm with a boron content of approximately 2.3 × 1021 cm3. Aberration-corrected HRTEM reveals the presence of defects within individual diamond grains, as well as a very thin nondiamond carbon layer at the particle surface. The boron K-edge electron energy-loss near-edge fine structure demonstrates that the B atoms are tetrahedrally embedded into the diamond lattice. The boron-doped diamond nanoparticles have been used to nucleate growth of a boron-doped diamond film by CVD that does not contain an insulating seeding layer. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000338089200039 |
Publication Date |
2014-04-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
71 |
Open Access |
|
|
Notes |
the Research Foundation Flanders (FWO-Vlaanderen) (G.0555.10N;G.0568.10N; G.0456.12; G0044.13N and a postdoctoral scholarship for S.T.); EU FP7 through Marie Curie ITN “MATCON” (PITNGA-127 2009-238201)the Collaborative Project “DINAMO” (No. 245122) Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2.; esteem2_jra3 |
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
|
Call Number |
UA @ lucian @ c:irua:117599 |
Serial |
3683 |
Permanent link to this record |
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Author |
Rossell, M.D.; Abakumov, A.M.; Ramasse, Q.M.; Erni, R. |
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Title |
Direct evidence of stacking disorder in the mixed ionic-electronic conductor Sr4Fe6O12+\delta |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
7 |
Issue |
4 |
Pages |
3078-3085 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Determining the structure-to-property relationship of materials becomes particularly challenging when the material under investigation is dominated by defects and structural disorder. Knowledge on the exact atomic arrangement at the defective structure is required to understand its influence on the functional properties. However, standard diffraction techniques deliver structural information that is averaged over many unit cells. In particular, information about defects and order-disorder phenomena is contained in the coherent diffuse scattering intensity which often is difficult to uniquely interpret. Thus, the examination of the local disorder in materials requires a direct method to study their structure on the atomic level with chemical sensitivity. Using aberration-corrected scanning transmission electron microscopy in combination with atomic-resolution electron energy-loss spectroscopy, we show that the controversial structural arrangement of the Fe2O2+delta layers in the mixed ionic-electronic conducting Sr4Fe6O12+delta perovskite can be unambiguously resolved. Our results provide direct experimental evidence for the presence of a nanomixture of “ordered” and “disordered” domains in an epitaxial Sr4Fe6O12+delta thin film. The most favorable arrangement is the disordered structure and is interpreted as a randomly occurring but well-defined local shift of the Fe-O chains in the Fe2O2+delta layers. By analyzing the electron energy-loss near-edge structure of the different building blocks in the Sr4Fe6O12+delta unit cell we find that the mobile holes in this mixed ionic-electronic conducting oxide are highly localized in the Fe2O2+delta layers, which are responsible for the oxide-ion conductivity. A possible link between disorder and oxygen-ion transport along the Fe2O2+delta layers is proposed by arguing that the disorder can effectively break the oxygen diffusion pathways. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000318143300021 |
Publication Date |
2013-03-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
4 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2013 IF: 12.033 |
|
Call Number |
UA @ lucian @ c:irua:108476 |
Serial |
713 |
Permanent link to this record |
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Author |
Quintana, M.; López, A.M.; Rapino, S.; Toma, F.M.; Iurlo, M.; Carraro, M.; Sartorel, A.; Maccato, C.; Ke, X.; Bittencourt, C.; Da Ros, T.; Van Tendeloo, G.; Marcaccio, M.; Paolucci, F.; Prato, M.; Bonchio, M.; |
|
Title |
Knitting the catalytic pattern of artificial photosynthesis to a hybrid graphene nanotexture |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
7 |
Issue |
1 |
Pages |
811-817 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
The artificial leaf project calls for new materials enabling multielectron catalysis with minimal overpotential, high turnover frequency, and long-term stability. Is graphene a better material than carbon nanotubes to enhance water oxidation catalysis for energy applications? Here we show that functionalized graphene with a tailored distribution of polycationic, quaternized, ammonium pendants provides an sp(2) carbon nanoplatform to anchor a totally inorganic tetraruthenate catalyst, mimicking the oxygen evolving center of natural PSII. The resulting hybrid material displays oxygen evolution at overpotential as low as 300 mV at neutral pH with negligible loss of performance after 4 h testing. This multilayer electroactive asset enhances the turnover frequency by 1 order of magnitude with respect to the isolated catalyst, and provides a definite up-grade of the carbon nanotube material, with a similar surface functionalization. Our innovation is based on a noninvasive, synthetic protocol for graphene functionalization that goes beyond the ill-defined oxidation-reduction methods, allowing a definite control of the surface properties. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000314082800088 |
Publication Date |
2012-12-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
69 |
Open Access |
|
|
Notes |
246791 COUNTATOMS; 262348 ESMI; ESF Cost Action NanoTP MP0901 |
Approved |
Most recent IF: 13.942; 2013 IF: 12.033 |
|
Call Number |
UA @ lucian @ c:irua:107707 |
Serial |
1766 |
Permanent link to this record |
|
|
|
|
Author |
Groeneveld, E.; Witteman, L.; Lefferts, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; de Mello Donega, C. |
|
Title |
Tailoring ZnSe-CdSe colloidal quantum dots via cation exchange : from core/shell to alloy nanocrystals |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
7 |
Issue |
9 |
Pages |
7913-7930 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
We report a study of Zn2+ by Cd2+ cation exchange (CE) in colloidal ZnSe nanocrystals (NCs). Our results reveal that CE in ZnSe NCs is a thermally activated isotropic process. The CE efficiency (i.e., fraction of Cd2+ ions originally in solution, Cdsol, that is incorporated in the ZnSe NC) increases with temperature and depends also on the Cdsol/ZnSe ratio. Interestingly, the reaction temperature can be used as a sensitive parameter to tailor both the composition and the elemental distribution profile of the product (Zn,Cd)Se NCs. At 150 °C ZnSe/CdSe core/shell hetero-NCs (HNCs) are obtained, while higher temperatures (200 and 220 °C) produce (Zn1xCdx)Se gradient alloy NCs, with increasingly smoother gradients as the temperature increases, until homogeneous alloy NCs are obtained at T ≥ 240 °C. Remarkably, sequential heating (150 °C followed by 220 °C) leads to ZnSe/CdSe core/shell HNCs with thicker shells, rather than (Zn1xCdx)Se gradient alloy NCs. Thermal treatment at 250 °C converts the ZnSe/CdSe core/shell HNCs into (Zn1xCdx)Se homogeneous alloy NCs, while preserving the NC shape. A mechanism for the cation exchange in ZnSe NCs is proposed, in which fast CE takes place at the NC surface, and is followed by relatively slower thermally activated solid-state cation diffusion, which is mediated by Frenkel defects. The findings presented here demonstrate that cation exchange in colloidal ZnSe NCs provides a very sensitive tool to tailor the nature and localization regime of the electron and hole wave functions and the optoelectronic properties of colloidal ZnSeCdSe NCs. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000330016900051 |
Publication Date |
2013-08-13 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
153 |
Open Access |
|
|
Notes |
262348 Esmi; 246791 Countatoms |
Approved |
Most recent IF: 13.942; 2013 IF: 12.033 |
|
Call Number |
UA @ lucian @ c:irua:110038 |
Serial |
3469 |
Permanent link to this record |
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|
|
Author |
Bertoni, G.; Grillo, V.; Brescia, R.; Ke, X.; Bals, S.; Catellani, A.; Li, H.; Manna, L. |
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Title |
Direct determination of polarity, faceting, and core location in colloidal core/shell wurtzite semiconductor nanocrystals |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
6 |
Issue |
7 |
Pages |
6453-6461 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
The ability to determine the atomic arrangement and termination of various facets of surfactant-coated nanocrystals is of great importance for understanding their growth mechanism and their surface properties and represents a critical piece of information that can be coupled to other experimental techniques and to calculations. This is especially appealing in the study of nanocrystals that can be grown in strongly anisotropic shapes, for which the relative growth rates of various facets can be influenced under varying reaction conditions. Here we show that in two representative cases of rod-shaped nanocrystals in the wurtzite phase (CdSe(core)/CdS(shell) and ZnSe(core)/ZnS(shell) nanorods) the terminations of the polar facets can be resolved unambiguously by combining advanced electron microscopy techniques, such as aberration-corrected HRTEM with exit wave reconstruction or aberration-corrected HAADF-STEM. The [0001] and [000-1] polar directions of these rods, which grow preferentially along their c-axis, are revealed clearly, with one side consisting of the Cd (or Zn)-terminated (0001) facet and the other side with a pronounced faceting due to Cd (or Zn)-terminated {10-1-1} facets. The lateral faceting of the rods is instead dominated by three nonpolar {10-10} facets. The core buried in the nanostructure can be localized in both the exit wave phase and HAADF-STEM images. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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|
Language |
|
Wos |
000306673800079 |
Publication Date |
2012-06-18 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
63 |
Open Access |
|
|
Notes |
The authors gratefully acknowledge funding from the European Research Council under grant number 240111 (NANO-ARCH) and the financial support from the Flemish Hercules 3 Programme for large infrastructures. G.B. and V.G. thank E. Rotunno for his help with STEM_CELL and IWFR. |
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
|
Call Number |
UA @ lucian @ c:irua:101138 |
Serial |
710 |
Permanent link to this record |
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Author |
Sánchez-Iglesias, A.; Grzelczak, M.; Altantzis, T.; Goris, B.; Pérez-Juste, J.; Bals, S.; Van Tendeloo, G.; Donaldson, S.H.; Chmelka, B.F.; Israelachvili, J.N.; Liz-Marzán, L.M.; |
|
Title |
Hydrophobic interactions modulate self-assembly of nanoparticles |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
6 |
Issue |
12 |
Pages |
11059-11065 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Hydrophobic interactions constitute one of the most important types of nonspecific interactions in biological systems, which emerge when water molecules rearrange as two hydrophobic species come close to each other. The prediction of hydrophobic interactions at the level of nanoparticles (Brownian objects) remains challenging because of uncontrolled diffusive motion of the particles. We describe here a general methodology for solvent-induced, reversible self-assembly of gold nanoparticles into 3D clusters with well-controlled sizes. A theoretical description of the process confirmed that hydrophobic interactions are the main driving force behind nanoparticle aggregation. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000312563600070 |
Publication Date |
2012-11-28 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
311 |
Open Access |
|
|
Notes |
267867 Plasma Quo; 246791 Countatoms; 262348 Esmi |
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
|
Call Number |
UA @ lucian @ c:irua:105292 |
Serial |
1538 |
Permanent link to this record |
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Author |
De Trizio, L.; Figuerola, A.; Manna, L.; Genovese, A.; George, C.; Brescia, R.; Saghi, Z.; Simonutti, R.; van Huis, M.; Falqui, A. |
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Title |
Size-tunable, hexagonal plate-like Cu3P and Janus-like Cu-Cu3P nanocrystals |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
6 |
Issue |
1 |
Pages |
32-41 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
We describe two synthesis approaches to colloidal Cu3P nanocrystals using trioctylphosphine (TOP) as phosphorus precursor. One approach is based on the homogeneous nucleation of small Cu3P nanocrystals with hexagonal plate-like morphology and with sizes that can be tuned from 5 to 50 nm depending on the reaction time. In the other approach, metallic Cu nanocrystals are nucleated first and then they are progressively phosphorized to Cu3P. In this case, intermediate Janus-like dimeric nanoparticles can be isolated, which are made of two domains of different materials, Cu and Cu3P, sharing a flat epitaxial interface. The Janus-like nanoparticles can be transformed back to single-crystalline copper particles if they are annealed at high temperature under high vacuum conditions, which makes them an interesting source of phosphorus. The features of the Cu Cu3P Janus-like nanoparticles are compared with those of the Wiped microstructure discovered more than two decades ago in the rapidly quenched Cu Cu3P eutectic of the Cu P alloy, suggesting that other alloy/eutectic systems that display similar behavior might give origin to nanostructures with flat, epitaxial Interface between domains of two diverse materials. Finally, the electrochemical properties of the copper phosphide plates are studied, and they are found to be capable of undergoing lithiation/delithiation through a displacement reaction, while the Janus-like Cu Cu3P particles do not display an electrochemical behavior that would make them suitable for applications in batteries. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000299368300006 |
Publication Date |
2011-12-03 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
60 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
|
Call Number |
UA @ lucian @ c:irua:99172 |
Serial |
3039 |
Permanent link to this record |
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Author |
Tognalii, N.G.; Cortés, E.; Hernández-Nieves, A.D.; Carro, P.; Usaj, G.; Balseiro, C.A.; Vela, M.E.; Salvarezza, R.C.; Fainstein, A. |
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Title |
From single to multiple Ag-layer modification of Au nanocavity substrates : a tunable probe of the chemical surface-enhanced Raman scattering mechanism |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
5 |
Issue |
7 |
Pages |
5433-5443 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
We present experimental and computational results that enlighten the mechanisms underlying the chemical contribution to surface-enhanced Raman scattering (SERS). Gold void metallic arrays electrochemically covered either by a Ag monolayer or 10100 Ag layers were modified with a self-assembled monolayer of 4-mercaptopyridine as a molecular Raman probe displaying a rich and unexpected Raman response. A resonant increase of the Raman intensity in the red part of the spectrum is observed that cannot be related to plasmon excitations of the cavity-array. Notably, we find an additional 1020 time increase of the SERS amplification upon deposition of a single Ag layer on the Au substrate, which is, however, almost quenched upon deposition of 10 atomic layers. Further deposition of 100 atomic Ag layers results in a new increase of the SERS signal, consistent with the improved plasmonic efficiency of Ag bulk-like structures. The SERS response as a function of the Ag layer thickness is analyzed in terms of ab initio calculations and a microscopic model for the SERS chemical mechanism based on a resonant charge transfer process between the molecular HOMO state and the Fermi level in the metal surface. We find that a rearrangement of the electronic charge density related to the presence of the Ag monolayer in the Au/Ag/molecule complex causes an increase in the distance between the HOMO center of charge and the metallic image plane that is responsible for the variation of Raman enhancement between the studied substrates. Our results provide a general platform for studying the chemical contribution to SERS, and for enhancing the Raman efficiency of tailored Au-SERS templates through electrochemical modification with Ag films. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000293035200019 |
Publication Date |
2011-06-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
26 |
Open Access |
|
|
Notes |
; We acknowledge financial support from ANPCyT (Argentina, PICT08-1617, PICT08-2236, PICT06-621, PICT-CNPQ-08-0019, PAE 22711, PICT06-01061, PICT06-483) and Project CTQ2008-06017/BQU, Spain. N.G.T, E.C., A.D.H.N., R.C.S, G.U., C.A.B., and A.F. are also at CONICET. M.E.V. is a member of the research career of CIC BsAs. R.C.S., C.A.B., and A.F. are Guggenheim Foundation Fellows. We would like to thank Dr. M. H. Fonticelli for fruitful discussions on the electrochemical measurements and Dr. H. Pastoriza for the help with the SEM measurements. ; |
Approved |
Most recent IF: 13.942; 2011 IF: 11.421 |
|
Call Number |
UA @ lucian @ c:irua:91775 |
Serial |
1285 |
Permanent link to this record |
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Author |
Neyts, E.C.; Shibuta, Y.; van Duin, A.C.T.; Bogaerts, A. |
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Title |
Catalyzed growth of carbon nanotube with definable chirality by hybrid molecular dynamics-force biased Monte Carlo simulations |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
4 |
Issue |
11 |
Pages |
6665-6672 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
Abstract |
Metal-catalyzed growth mechanisms of carbon nanotubes (CNTs) were studied by hybrid molecular dynamics−Monte Carlo simulations using a recently developed ReaxFF reactive force field. Using this novel approach, including relaxation effects, a CNT with definable chirality is obtained, and a step-by-step atomistic description of the nucleation process is presented. Both root and tip growth mechanisms are observed. The importance of the relaxation of the network is highlighted by the observed healing of defects. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000284438000043 |
Publication Date |
2010-10-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
129 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2010 IF: 9.865 |
|
Call Number |
UA @ lucian @ c:irua:84759 |
Serial |
294 |
Permanent link to this record |
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Author |
Quintana, M.; Ke, X.; Van Tendeloo, G.; Meneghetti, M.; Bittencourt, C.; Prato, M. |
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Title |
Light-induced selective deposition of Au nanoparticles on single-wall carbon nanotubes |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
4 |
Issue |
10 |
Pages |
6105-6113 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Novel applications of single-walled carbon nanotubes (SWNT) rely on the development of new strategies to make them easier to handle without affecting their structural properties. In this work, we have selectively deposited Au nanoparticles (Au NP) on SWNT assisted by UV light irradiation. XPS analysis and UV-vis spectroscopy indicate that the deposition occurs at the defects generated after oxidation of the SWNT. By addition of n-dodecylthiol, the separation of oxidized tubes with Au NP (Au-ox-SWNT) from tubes devoid of Au NP (bare tubes, b-SWNT) was achieved. Raman and UV-vis-NIR spectra indicate that UV irradiation induces a faster nucleation of Au NP on metallic SWNT. This new technique can be useful for the preparation of nanohybrid composites with enhanced properties, as increased thermal stability, and to obtain purified SWNT. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000283453700081 |
Publication Date |
2010-09-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
26 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2010 IF: 9.865 |
|
Call Number |
UA @ lucian @ c:irua:99202 |
Serial |
1819 |
Permanent link to this record |
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Author |
Felten, A.; Gillon, X.; Gulas, M.; Pireaux, J.-J.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Najafi, E.; Hitchcock, A.P. |
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Title |
Measuring point defect density in individual carbon nanotubes using polarization-dependent X-ray microscopy |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
4 |
Issue |
8 |
Pages |
4431-4436 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
The presence of defects in carbon nanotubes strongly modifies their electrical, mechanical, and chemical properties. It was long thought undesirable, but recent experiments have shown that introduction of structural defects using ion or electron irradiation can lead to novel nanodevices. We demonstrate a method for detecting and quantifying point defect density in individual carbon nanotubes (CNTs) based on measuring the polarization dependence (linear dichroism) of the C 1s → π* transition at specific locations along individual CNTs with a scanning transmission X-ray microscope (STXM). We show that STXM can be used to probe defect density in individual CNTs with high spatial resolution. The quantitative relationship between ion dose, nanotube diameter, and defect density was explored by purposely irradiating selected sections of nanotubes with kiloelectronvolt (keV) Ga+ ions. Our results establish polarization-dependent X-ray microscopy as a new and very powerful characterization technique for carbon nanotubes and other anisotropic nanostructures. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281052700014 |
Publication Date |
2010-07-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
26 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2010 IF: 9.865 |
|
Call Number |
UA @ lucian @ c:irua:84734 |
Serial |
1966 |
Permanent link to this record |
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Author |
Suarez-Martinez, I.; Ewels, C.P.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Felten, A.; Pireaux, J.-J.; Ghijsen, J.; Bittencourt, C. |
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Title |
Study of the interface between rhodium and carbon nanotubes |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
|
Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
4 |
Issue |
3 |
Pages |
1680-1686 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
X-ray photoelectron spectroscopy at 3.5 keV photon energy, in combination with high-resolution transmission electron microscopy, is used to follow the formation of the interface between rhodium and carbon nanotubes. Rh nucleates at defect sites, whether initially present or induced by oxygen-plasma treatment. More uniform Rh cluster dispersion is observed on plasma-treated CNTs. Experimental results are compared to DFT calculations of small Rh clusters on pristine and defective graphene. While Rh interacts as strongly with the carbon as Ti, it is less sensitive to the presence of oxygen, suggesting it as a good candidate for nanotube contacts. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000275858200053 |
Publication Date |
2010-02-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
13.942 |
Times cited |
26 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 13.942; 2010 IF: 9.865 |
|
Call Number |
UA @ lucian @ c:irua:82440 |
Serial |
3337 |
Permanent link to this record |
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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 ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
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. |
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Address |
School of Physics and Astronomy, University of Manchester , Manchester M13 9PL, United Kingdom |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000372855400073 |
Publication Date |
2016-02-16 |
|
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 |
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 |
Permanent link to this record |
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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. |
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Title |
Electronic Coupling between Graphene and Topological Insulator Induced Anomalous Magnetotransport Properties |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume ![sorted by Volume (numeric) field, descending order (down)](img/sort_desc.gif) |
11 |
Issue |
11 |
Pages |
6277-6285 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000404808000110 |
Publication Date |
2017-05-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
12 |
Open Access |
OpenAccess |
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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 |
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Call Number |
EMAT @ emat @ c:irua:143192 |
Serial |
4569 |
Permanent link to this record |