Records |
Author |
Sandoval, S.; Kepic, D.; Perez del Pino, A.; Gyorgy, E.; Gomez, A.; Pfannmöller, M.; Van Tendeloo, G.; Ballesteros, B.; Tobias, G. |
Title |
Selective laser-assisted synthesis of tubular van der Waals heterostructures of single-layered PbI2 within carbon nanotubes exhibiting carrier photogeneration |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
12 |
Issue |
7 |
Pages |
6648-6656 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The electronic and optical properties of two-dimensional layered materials allow the miniaturization of nanoelectronic and optoelectronic devices in a competitive manner. Even larger opportunities arise when two or more layers of different materials are combined. Here, we report on an ultrafast energy efficient strategy, using laser irradiation, which allows bulk synthesis of crystalline single-layered lead iodide in the cavities of carbon nanotubes by forming cylindrical van der Waals heterostructures. In contrast to the filling of van der Waals solids into carbon nanotubes by conventional thermal annealing, which favors the formation of inorganic nanowires, the present strategy is highly selective toward the growth of monolayers forming lead iodide nanotubes. The irradiated bulk material bearing the nanotubes reveals a decrease of the resistivity as well as a significant increase in the current flow upon illumination. Both effects are attributed to the presence of single-walled lead iodide nanotubes in the cavities of carbon nanotubes, which dominate the properties of the whole matrix. The present study brings in a simple, ultrafast and energy efficient strategy for the tailored synthesis of rolled-up single-layers of lead iodide (i.e., single-walled PbI2 nanotubes), which we believe could be expanded to other two-dimensional (2D) van der Waals solids. In fact, initial tests with ZnI2 already reveal the formation of single-walled ZnI2 nanotubes, thus proving the versatility of the approach. |
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 |
000440505000029 |
Publication Date |
2018-07-05 |
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 |
|
ISSN |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
8 |
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; We acknowledge funding from MINECO (Spain), through MAT2017-86616-R, ENE2017-89210-C2-1-R, and “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0496, SEV-2013-0295), CERCA programme for funding ICN2 and support from AGAUR of Generalitat de Catalunya through the projects 2017 SGR 1086, 2017 SGR 581 and 2017 SGR 327. We thank Thomas Swan Co., Ltd., for supplying MWCNT Elicarb samples. D.K. acknowledges financial support from the Ministry of Education, Science, and Technological Development of the Republic of Serbia for postdoctoral research. We are grateful to R Rurali (ICMAB-CSIC) for providing the structural model of the PbI<INF>2</INF> nanotube employed for the schematic representation of PbI<INF>2</INF>@MVWCNT. ; |
Approved |
Most recent IF: 13.942 |
Call Number |
UA @ lucian @ c:irua:153169 |
Serial |
5127 |
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. |
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 |
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. |
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 |
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 |
26 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; 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 |
Jishkariani, D.; Elbert, K.C.; Wu, Y.; Lee, J.D.; Hermes, M.; Wang, D.; van Blaaderen, A.; Murray, C.B. |
Title |
Nanocrystal Core Size and Shape Substitutional Doping and Underlying Crystalline Order in Nanocrystal Superlattices |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
13 |
Issue |
5 |
Pages |
5712-5719 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Substitutional doping is a potentially powerful technique to control the properties of nanocrystal (NC) superlattices (SLs). However, not every NC can be substituted into any lattice, as the NCs have to be close in size and shape, limiting the application of substitutional doping. Here we show that this limitation can be overcome by employing ligands of various size. We show that small NCs with long ligands can be substituted into SLs of big NCs with short ligands. Furthermore, we show that shape differences can also be overcome and that cubes can substitute spheres when both are coated with long ligands. Finally, we use the NC effective ligand size, softness, and effective overall size ratio to explain observed doping behaviors. |
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 |
000469886300078 |
Publication Date |
2019-05-03 |
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 |
|
ISSN |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
6 |
Open Access |
Not_Open_Access |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; This work was supported by the University of Pennsylvania's NSF MRSEC under award no. DMR-112090 and the CNRS-UPENN-SOLVAY through the Complex Assemblies of Soft Matter Laboratory (COMPASS). K.C.E. acknowledges support from the NSF Graduate Research Fellowship Program under grant no. DGE-1321851. C.B.M. acknowledges the Richard Perry University Professorship at the University of Pennsylvania. D.W. and A.v.B. acknowledge partial funding from the European Research Council under the European Union's Seventh Framework Programme (FP -2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. M.H. was supported by The Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation programme funded by the Ministry of Education, Culture and Science of the government of The Netherlands. The authors thank EM square in Utrecht University for the access to the microscopes. ; |
Approved |
Most recent IF: 13.942 |
Call Number |
UA @ admin @ c:irua:160344 |
Serial |
5256 |
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. |
Title |
Environmental changes in MoTe2 excitonic dynamics by defects-activated molecular interaction |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
9 |
Issue |
9 |
Pages |
5326-5332 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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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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 |
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 |
150 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; 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 |
Call Number |
c:irua:126441 |
Serial |
1068 |
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. |
Title |
Electronic Coupling between Graphene and Topological Insulator Induced Anomalous Magnetotransport Properties |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
11 |
Issue |
11 |
Pages |
6277-6285 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
It has been theoretically proposed that the spin textures of surface states in a topological insulator can be directly transferred to graphene by means of the proximity effect, which is very important for realizing the two-dimensional topological insulator based on graphene. Here we report the anomalous magnetotransport properties of graphene-topological insulator Bi2Se3 heterojunctions, which are sensitive to the electronic coupling between graphene and the topological surface state. The coupling between the p_z orbitals of graphene and the p orbitals of the surface states on the Bi2Se3 bottom surface can be enhanced by applying a perpendicular negative magnetic field, resulting in a giant negative magnetoresistance at the Dirac point up to about -91%. Obvious resistances dip in the transfer curve at the Dirac point is also observed in the hybrid devices, which is consistent with theoretical predictions of the distorted Dirac bands with nontrivial spin textures inherited from the Bi2Se3 surface states. |
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 |
000404808000110 |
Publication Date |
2017-05-10 |
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 |
|
ISSN |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
12 |
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; This work was supported by National Key Research and Development Program of China (Nos. 2016YFA0300802, 2013CB934600) and NSFC (No. 11234001). ; |
Approved |
Most recent IF: 13.942 |
Call Number |
EMAT @ emat @ c:irua:143192 |
Serial |
4569 |
Permanent link to this record |
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Author |
Gonzalez-Rubio, G.; Kumar, V.; Llombart, P.; Diaz-Nunez, P.; Bladt, E.; Altantzis, T.; Bals, S.; Pena-Rodriguez, O.; Noya, E.G.; MacDowell, L.G.; Guerrero-Martinez, A.; Liz-Marzan, L.M. |
Title |
Disconnecting Symmetry Breaking from Seeded Growth for the Reproducible Synthesis of High Quality Gold Nanorods |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
13 |
Issue |
13 |
Pages |
4424-4435 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
One of the major difficulties hindering the widespread application of colloidal anisotropic plasmonic nanoparticles is the limited robustness and reproducibility of multistep synthetic methods. We demonstrate herein that the reproducibility and reliability of colloidal gold nanorod (AuNR) synthesis can be greatly improved by disconnecting the symmetry-breaking event from the seeded growth process. We have used a modified silver-assisted seeded growth method in the presence of the surfactant hexadecyltrimethylammonium bromide and n-decanol as a co-surfactant to prepare small AuNRs in high yield, which were then used as seeds for the growth of high quality AuNR colloids. Whereas the use of n-decanol provides a more-rigid micellar system, the growth on anisotropic seeds avoids sources of irreproducibility during the symmetry breaking step, yielding uniform AuNR colloids with narrow plasmon bands, ranging from 600 to 1270 nm, and allowing the fine-tuning of the final dimensions. This method provides a robust route for the preparation of high quality AuNR colloids with tunable morphology, size, and optical response in a reproducible and scalable manner. |
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 |
000466052900067 |
Publication Date |
2019-04-02 |
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 |
Impact Factor |
13.942 |
Times cited |
100 |
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; This work has been funded by the Spanish MINECO (grant nos. FIS2017-89361-C3-2-P and MAT2017-86659-R), the Madrid Regional Government (grant no. P2018/NMT-4389) and the Complutense University of Madrid (grant no. PR75/18-21616). Funding is acknowledged from the European Commission (grant no. EUSMI 731019). G.G.-R. acknowledges receipt of FPI Fellowship from the Spanish MINECO. E.B. and T.A. acknowledge postdoctoral grants from the Research Foundation Flanders (FWO). The authors are indebted to Profs. Justin Gooding, Watson Loh, Nicholas Kotov, Deqing Zhang, Mihaela Delcea, Maurizio Prato, and Krishna Ganesh, for providing milli-Q water samples. ; |
Approved |
Most recent IF: 13.942 |
Call Number |
UA @ admin @ c:irua:160417 |
Serial |
5246 |
Permanent link to this record |
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Author |
Griffin, E.; Mogg, L.; Hao, G.-P.; Kalon, G.; Bacaksiz, C.; Lopez-Polin, G.; Zhou, T.Y.; Guarochico, V.; Cai, J.; Neumann, C.; Winter, A.; Mohn, M.; Lee, J.H.; Lin, J.; Kaiser, U.; Grigorieva, I., V; Suenaga, K.; Ozyilmaz, B.; Cheng, H.-M.; Ren, W.; Turchanin, A.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
Title |
Proton and Li-Ion permeation through graphene with eight-atom-ring defects |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
Volume |
14 |
Issue |
6 |
Pages |
7280-7286 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Defect-free graphene is impermeable to gases and liquids but highly permeable to thermal protons. Atomic-scale defects such as vacancies, grain boundaries, and Stone-Wales defects are predicted to enhance graphene's proton permeability and may even allow small ions through, whereas larger species such as gas molecules should remain blocked. These expectations have so far remained untested in experiment. Here, we show that atomically thin carbon films with a high density of atomic-scale defects continue blocking all molecular transport, but their proton permeability becomes similar to 1000 times higher than that of defect-free graphene. Lithium ions can also permeate through such disordered graphene. The enhanced proton and ion permeability is attributed to a high density of eight-carbon-atom rings. The latter pose approximately twice lower energy barriers for incoming protons compared to that of the six-atom rings of graphene and a relatively low barrier of similar to 0.6 eV for Li ions. Our findings suggest that disordered graphene could be of interest as membranes and protective barriers in various Li-ion and hydrogen technologies. |
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 |
000543744100086 |
Publication Date |
2020-05-19 |
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 |
|
ISSN |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
17.1 |
Times cited |
53 |
Open Access |
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Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; The work was supported by the Lloyd's Register Foundation, EPSRC-EP/N010345/1, the European Research Council, the Graphene Flagship, the Deutsche Forschungsgemeinschaft project TRR 234 “CataLight” (Project B7, Grant No. 364549901), and the research infrastructure Grant No. INST 275/25 7-1 FUGG. E.G. and L.M. acknowledge the EPSRC NowNANO programme for funding. ; |
Approved |
Most recent IF: 17.1; 2020 IF: 13.942 |
Call Number |
UA @ admin @ c:irua:170708 |
Serial |
6586 |
Permanent link to this record |
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Author |
Hinterding, S.O.M.; Berends, A.C.; Kurttepeli, M.; Moret, M.-E.; Meeldijk, J.D.; Bals, S.; van der Stam, W.; de Donega, C.M. |
Title |
Tailoring Cu+ for Ga3+ cation exchange in Cu2-xS and CuInS2 nanocrystals by controlling the Ga precursor chemistry |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
13 |
Issue |
13 |
Pages |
12880-12893 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Nanoscale cation exchange (CE) has resulted in colloidal nanomaterials that are unattainable by direct synthesis methods. Aliovalent CE is complex and synthetically challenging because the exchange of an unequal number of host and guest cations is required to maintain charge balance. An approach to control aliovalent CE reactions is the use of a single reactant to both supply the guest cation and extract the host cation. Here, we study the application of GaCl3-L complexes [L = trioctylphosphine (TOP), triphenylphosphite (TPP), diphenylphosphine (DPP)] as reactants in the exchange of Cu+ for Ga3+ in Cu2-xS nanocrystals. We find that noncomplexed GaCl3 etches the nanocrystals by S2- extraction, whereas GaCl3-TOP is unreactive. Successful exchange of Cu+ for Ga3+ is only possible when GaCl3 is complexed with either TPP or DPP. This is attributed to the pivotal role of the Cu2-xS-GaCl3-L activated complex that forms at the surface of the nanocrystal at the onset of the CE reaction, which must be such that simultaneous Ga3+ insertion and Cu+ extraction can occur. This requisite is only met if GaCl3 is bound to a phosphine ligand, with a moderate bond strength, to allow facile dissociation of the complex at the nanocrystal surface. The general validity of this mechanism is demonstrated by using GaCl3-DPP to convert CuInS2 into (Cu,Ga,In)S-2 nanocrystals, which increases the photoluminescence quantum yield 10 -fold, while blue -shifting the photoluminescence into the NIR biological window. This highlights the general applicability of the mechanistic insights provided by our work. |
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 |
000500650000061 |
Publication Date |
2019-10-16 |
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 |
Impact Factor |
13.942 |
Times cited |
27 |
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; S.O.M.H., W.v.d.S., A.C.B., and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under Grant Nos. ECHO.712.012.0001 and ECHO.712.014.001. S.B. acknowledges financial support from the European Research Council (ERC Consolidator Grant No. 815128-REALNANO). S.O.M.H. is supported by The Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation Programme funded by the Ministry of Education, Culture and Science of the government of The Netherlands. DFT calculations were carried out on the Dutch national e-infrastructure with the support of SURF Cooperative. This work was sponsored by NWO Physical Sciences for the use of supercomputer facilities. The authors thank Jessi van der Hoeven for EDS and TEM measurements. ; sygma |
Approved |
Most recent IF: 13.942 |
Call Number |
UA @ admin @ c:irua:165149 |
Serial |
6324 |
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 |
10 |
Issue |
10 |
Pages |
3685-3692 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
The rate of water flow through hydrophobic nanocapillaries is greatly enhanced as compared to that expected from macroscopic hydrodynamics. This phenomenon is usually described in terms of a relatively large slip length, which is in turn defined by such microscopic properties as the friction between water and capillary surfaces and the viscosity of water. We show that the viscosity of water and, therefore, its flow rate are profoundly affected by the layered structure of confined water if the capillary size becomes less than 2 nm. To this end, we study the structure and dynamics of water confined between two parallel graphene layers using equilibrium molecular dynamics simulations. We find that the shear viscosity is not only greatly enhanced for subnanometer capillaries, but also exhibits large oscillations that originate from commensurability between the capillary size and the size of water molecules. Such oscillating behavior of viscosity and, consequently, the slip length should be taken into account in designing and studying graphene-based and similar membranes for desalination and filtration. |
Address |
School of Physics and Astronomy, University of Manchester , Manchester M13 9PL, United Kingdom |
Corporate Author |
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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 |
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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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
160 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; 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 |
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 |
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. |
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 |
000333539400085 |
Publication Date |
2014-02-05 |
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 |
38 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; 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 |
Fedoseeva, Y.V.; Orekhov, A.S.; Chekhova, G.N.; Koroteev, V.O.; Kanygin, M.A.; Seovskiy, B.V.; Chuvilin, A.; Pontiroli, D.; Ricco, M.; Bulusheva, L.G.; Okotrub, A.V. |
Title |
Single-walled carbon nanotube reactor for redox transformation of mercury dichloride |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
11 |
Issue |
9 |
Pages |
8643-8649 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('Single-walled carbon nanotubes (SWCNTs) possessing a confined inner space protected by chemically resistant shells are promising for delivery, storage, and desorption of various compounds, as well as carrying out specific reactions. Here, we show that SWCNTs interact with molten mercury dichloride (HgCl2) and guide its transformation into dimercury dichloride (Hg2Cl2) in the cavity. The chemical state of host SWCNTs remains almost unchanged except for a small p-doping from the guest Hg2Cl2 nanocrystals. The density functional theory calculations reveal that the encapsulated HgCl2 molecules become negatively charged and start interacting via chlorine bridges when local concentration increases. This reduces the bonding strength in HgCl2, which facilitates removal of chlorine, finally leading to formation of Hg2Cl2 species. The present work demonstrates that SWCNTs not only serve as a template for growing nanocrystals but also behave as an electron-transfer catalyst in the spatially confined redox reaction by donation of electron density for temporary use by the guests.')); |
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 |
000411918200012 |
Publication Date |
2017-08-07 |
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 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
11 |
Open Access |
Not_Open_Access |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; Collaboration between partner institutions was partially supported by European FP7 IRSES project 295180. We are grateful to the bilateral Program “Russian-German Laboratory at BESSY II” for the assistance in XPS and NEXAFS measurements. We acknowledge C. Tollan for proofreading the manuscript. We are grateful to Dr. Y.V. Shubin for XRD measurements of graphite with HgCl<INF>2</ INF>. ; |
Approved |
Most recent IF: 13.942 |
Call Number |
UA @ lucian @ c:irua:146770 |
Serial |
4895 |
Permanent link to this record |
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Author |
Sun, C.; Liao, X.; Xia, F.; Zhao, Y.; Zhang, L.; Mu, S.; Shi, S.; Li, Y.; Peng, H.; Van Tendeloo, G.; Zhao, K.; Wu, J. |
Title |
High-voltage cycling induced thermal vulnerability in LiCoO₂ cathode : cation loss and oxygen release driven by oxygen vacancy migration |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
Volume |
14 |
Issue |
5 |
Pages |
6181-6190 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The release of the lattice oxygen due to the thermal degradation of layered lithium transition metal oxides is one of the major safety concerns in Li-ion batteries. The oxygen release is generally attributed to the phase transitions from the layered structure to spinel and rocksalt structures that contain less lattice oxygen. Here, a different degradation pathway in LiCoO2 is found, through oxygen vacancy facilitated cation migration and reduction. This process leaves undercoordinated oxygen that gives rise to oxygen release while the structure integrity of the defect-free region is mostly preserved. This oxygen release mechanism can be called surface degradation due to the kinetic control of the cation migration but has a slow surface to bulk propagation with continuous loss of the surface cation ions. It is also strongly correlated with the high-voltage cycling defects that end up with a significant local oxygen release at low temperatures. This work unveils the thermal vulnerability of high-voltage Li-ion batteries and the critical role of the surface fraction as a general mitigating approach. |
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 |
000537682300101 |
Publication Date |
2020-04-17 |
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 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
17.1 |
Times cited |
8 |
Open Access |
Not_Open_Access |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
; C.S., X.L., and F.X. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (21905169). The S/TEM work was performed at the Nanostructure Research Center (NRC), which is supported by the Fundamental Research Funds for the Central Universities (WUT: 2019III012GX), the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, and the State Key Laboratory of Silicate Materials for Architectures (all of the laboratories are at Wuhan University of Technology). ; |
Approved |
Most recent IF: 17.1; 2020 IF: 13.942 |
Call Number |
UA @ admin @ c:irua:170246 |
Serial |
6537 |
Permanent link to this record |
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Author |
Goris, B.; Turner, S.; Bals, S.; Van Tendeloo, G. |
Title |
Three-dimensional valency mapping in ceria nanocrystals |
Type |
A1 Journal article |
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
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. |
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 |
000343952600126 |
Publication Date |
2014-10-06 |
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 |
85 |
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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 |
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. |
Title |
Air- and water-resistant noble metal coated ferromagnetic cobalt nanorods |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
9 |
Issue |
9 |
Pages |
2792-2804 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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. |
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 |
000351791800055 |
Publication Date |
2015-03-03 |
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 |
|
Edition |
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
25 |
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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 |
Call Number |
c:irua:125380 c:irua:125380 |
Serial |
87 |
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 |
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. |
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 |
000332059200032 |
Publication Date |
2014-01-07 |
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 |
144 |
Open Access |
Not_Open_Access |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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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 |
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. |
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 |
000312563600070 |
Publication Date |
2012-11-28 |
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 |
|
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 ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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 |
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 |
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. |
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 |
000330016900051 |
Publication Date |
2013-08-13 |
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 |
Impact Factor |
13.942 |
Times cited |
153 |
Open Access |
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Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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 |
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 |
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. |
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 |
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 |
69 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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 |
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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.; |
Title |
Photovoltaic effect and evidence of carrier multiplication in graphene vertical homojunctions with asymmetrical metal contacts |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
9 |
Issue |
9 |
Pages |
8851-8858 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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. |
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 |
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 |
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
11 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
246791 Countatoms |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
Call Number |
c:irua:127689 |
Serial |
2615 |
Permanent link to this record |
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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 |
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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Place of Publication |
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Language |
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Wos |
000330542900092 |
Publication Date |
2013-12-31 |
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 |
39 |
Open Access |
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Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
Call Number |
UA @ lucian @ c:irua:114871 |
Serial |
276 |
Permanent link to this record |
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Author |
Neyts, E.C.; Shibuta, Y.; van Duin, A.C.T.; Bogaerts, A. |
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 |
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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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 |
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 |
129 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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 |
Rossell, M.D.; Abakumov, A.M.; Ramasse, Q.M.; Erni, R. |
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 |
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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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000318143300021 |
Publication Date |
2013-03-04 |
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 |
|
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 ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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.; Ke, X.; Van Tendeloo, G.; Meneghetti, M.; Bittencourt, C.; Prato, M. |
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 |
4 |
Issue |
10 |
Pages |
6105-6113 |
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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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 |
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 |
|
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 ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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 |
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 |
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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Corporate Author |
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Thesis |
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Place of Publication |
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Language |
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Wos |
000340992300025 |
Publication Date |
2014-08-09 |
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 |
23 |
Open Access |
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Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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 |
Felten, A.; Gillon, X.; Gulas, M.; Pireaux, J.-J.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Najafi, E.; Hitchcock, A.P. |
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 |
4 |
Issue |
8 |
Pages |
4431-4436 |
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. |
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 |
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 |
26 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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 |
De Trizio, L.; Figuerola, A.; Manna, L.; Genovese, A.; George, C.; Brescia, R.; Saghi, Z.; Simonutti, R.; van Huis, M.; Falqui, A. |
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 |
6 |
Issue |
1 |
Pages |
32-41 |
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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Place of Publication |
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Language |
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Wos |
000299368300006 |
Publication Date |
2011-12-03 |
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 |
60 |
Open Access |
|
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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 |
Suarez-Martinez, I.; Ewels, C.P.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Felten, A.; Pireaux, J.-J.; Ghijsen, J.; Bittencourt, C. |
Title |
Study of the interface between rhodium and carbon nanotubes |
Type |
A1 Journal article |
Year |
2010 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
4 |
Issue |
3 |
Pages |
1680-1686 |
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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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 |
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 |
26 |
Open Access |
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Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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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 |
Frolov, A.S.; Sanchez-Barriga, J.; Callaert, C.; Hadermann, J.; Fedorov, A., V; Usachov, D.Y.; Chaika, A.N.; Walls, B.C.; Zhussupbekov, K.; Shvets, I., V.; Muntwiler, M.; Amati, M.; Gregoratti, L.; Varykhalov, A.Y.; Rader, O.; Yashina, L., V. |
Title |
Atomic and electronic structure of a multidomain GeTe crystal |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
Volume |
14 |
Issue |
12 |
Pages |
16576-16589 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Renewed interest in the ferroelectric semi-conductor germanium telluride was recently triggered by the direct observation of a giant Rashba effect and a 30-year-old dream about a functional spin field-effect transistor. In this respect, all-electrical control of the spin texture in this material in combination with ferroelectric properties at the nanoscale would create advanced functionalities in spintronics and data information processing. Here, we investigate the atomic and electronic properties of GeTe bulk single crystals and their (111) surfaces. We succeeded in growing crystals possessing solely inversion domains of similar to 10 nm thickness parallel to each other. Using HAADF-TEM we observe two types of domain boundaries, one of them being similar in structure to the van der Waals gap in layered materials. This structure is responsible for the formation of surface domains with preferential Te-termination (similar to 68%) as we determined using photoelectron diffraction and XPS. The lateral dimensions of the surface domains are in the range of similar to 10-100 nm, and both Ge- and Te-terminations reveal no reconstruction. Using spin-ARPES we establish an intrinsic quantitative relationship between the spin polarization of pure bulk states and the relative contribution of different terminations, a result that is consistent with a reversal of the spin texture of the bulk Rashba bands for opposite configurations of the ferroelectric polarization within individual nanodomains. Our findings are important for potential applications of ferroelectric Rashba semiconductors in nonvolatile spintronic devices with advanced memory and computing capabilities at the nanoscale. |
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Place of Publication |
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Wos |
000603308800022 |
Publication Date |
2020-11-02 |
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 |
Impact Factor |
17.1 |
Times cited |
|
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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Approved |
Most recent IF: 17.1; 2020 IF: 13.942 |
Call Number |
UA @ admin @ c:irua:175027 |
Serial |
6716 |
Permanent link to this record |
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Author |
Scolfaro, D.; Finamor, M.; Trinchao, L.O.; Rosa, B.L.T.; Chaves, A.; Santos, P., V.; Iikawa, F.; Couto, O.D.D., Jr. |
Title |
Acoustically driven stark effect in transition metal dichalcogenide monolayers |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
Volume |
15 |
Issue |
9 |
Pages |
15371-15380 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
The Stark effect is one of the most efficient mechanisms to manipulate many-body states in nanostructured systems. In mono- and few-layer transition metal dichalcogenides, it has been successfully induced by optical and electric field means. Here, we tune the optical emission energies and dissociate excitonic states in MoSe2 monolayers employing the 220 MHz in-plane piezoelectric field carried by surface acoustic waves. We transfer the monolayers to high dielectric constant piezoelectric substrates, where the neutral exciton binding energy is reduced, allowing us to efficiently quench (above 90%) and red-shift the excitonic optical emissions. A model for the acoustically induced Stark effect yields neutral exciton and trion in-plane polarizabilities of 530 and 630 x 10(-5) meV/(kV/cm)(2), respectively, which are considerably larger than those reported for monolayers encapsulated in hexagonal boron nitride. Large in-plane polarizabilities are an attractive ingredient to manipulate and modulate multiexciton interactions in two-dimensional semiconductor nanostructures for optoelectronic applications. |
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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 |
000703553600129 |
Publication Date |
2021-08-27 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
|
Open Access |
OpenAccess |
Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
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Approved |
Most recent IF: 13.942 |
Call Number |
UA @ admin @ c:irua:182545 |
Serial |
7415 |
Permanent link to this record |