Records |
Author |
Tong, Y.; Yao, E.-P.; Manzi, A.; Bladt, E.; Wang, K.; Doeblinger, M.; Bals, S.; Mueller-Buschbaum, P.; Urban, A.S.; Polavarapu, L.; Feldmann, J. |
Title |
Spontaneous self-assembly of Perovskite nanocrystals into electronically coupled supercrystals : toward filling the green gap |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
30 |
Issue |
30 |
Pages |
1801117 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Self-assembly of nanoscale building blocks into ordered nanoarchitectures has emerged as a simple and powerful approach for tailoring the nanoscale properties and the opportunities of using these properties for the development of novel optoelectronic nanodevices. Here, the one-pot synthesis of CsPbBr3 perovskite supercrystals (SCs) in a colloidal dispersion by ultrasonication is reported. The growth of the SCs occurs through the spontaneous self-assembly of individual nanocrystals (NCs), which form in highly concentrated solutions of precursor powders. The SCs retain the high photoluminescence (PL) efficiency of their NC subunits, however also exhibit a redshifted emission wavelength compared to that of the individual nanocubes due to interparticle electronic coupling. This redshift makes the SCs pure green emitters with PL maxima at approximate to 530-535 nm, while the individual nanocubes emit a cyan-green color (approximate to 512 nm). The SCs can be used as an emissive layer in the fabrication of pure green light-emitting devices on rigid or flexible substrates. Moreover, the PL emission color is tunable across the visible range by employing a well-established halide ion exchange reaction on the obtained CsPbBr3 SCs. These results highlight the promise of perovskite SCs for light emitting applications, while providing insight into their collective optical 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 |
Weinheim |
Editor |
|
Language |
|
Wos |
000438709400019 |
Publication Date |
2018-06-05 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
161 |
Open Access |
OpenAccess |
Notes |
; This research work was supported by the Bavarian State Ministry of Science, Research, and Arts through the grant “Solar Technologies go Hybrid (SolTech),” by the China Scholarship Council (Y.T. and K.W.), by the European Union's Horizon 2020 research and innovation program under the Marie Skodowska-Curie Grant Agreement COMPASS No. 691185 and by LMU Munich's Institutional Strategy LMUexcellent within the framework of the German Excellence Initiative (L.P., J.F. and A.S.U.). E.B. and S.B. acknowledge financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). The authors would like to thank Alexander Richter for helpful discussions. ; ecas_Sara |
Approved |
Most recent IF: 19.791 |
Call Number |
UA @ lucian @ c:irua:152413UA @ admin @ c:irua:152413 |
Serial |
5129 |
Permanent link to this record |
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Author |
Kalashami, H.G.; Neek-Amal, M.; Peeters, F.M. |
Title |
Slippage dynamics of confined water in graphene oxide capillaries |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review materials |
Abbreviated Journal |
|
Volume |
2 |
Issue |
7 |
Pages |
074004 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The permeation of water between neighboring graphene oxide (GO) flakes, i.e., 2D nanochannels, are investigated using a simple model for the GO membrane. We simulate the hydrophilic behavior of nanocapillaries and study the effect of surface charge on the dynamical properties of water flow and the influence of Na+ and Cl- ions on water permeation. Our approach is based on extensive equilibrium molecular dynamics simulations to obtain a better understanding of water permeation through charged nanochannels in the presence of ions. We found significant change in the slippage dynamics of confined water such as a profound increase in viscosity/slip length with increasing charges over the surface. The slip length decreases one order of magnitude (i.e., 1/30) with increasing density of surface charge, while it increases by a factor of 2 with ion concentration. We found that commensurability induced by nanoconfinement plays an important role on the intrinsic dynamical properties of water. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
College Park, Md |
Editor |
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Language |
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Wos |
000439435200006 |
Publication Date |
2018-07-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2475-9953 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
|
Notes |
; We acknowledge fruitful discussions with Andre K. Geim, Irina Grigorieva, and Rahul R. Nair. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:152409UA @ admin @ c:irua:152409 |
Serial |
5128 |
Permanent link to this record |
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Author |
Sandoval, S.; Kepic, D.; Perez del Pino, A.; Gyorgy, E.; Gomez, A.; Pfannmöller, M.; Van Tendeloo, G.; Ballesteros, B.; Tobias, G. |
Title |
Selective laser-assisted synthesis of tubular van der Waals heterostructures of single-layered PbI2 within carbon nanotubes exhibiting carrier photogeneration |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
12 |
Issue |
7 |
Pages |
6648-6656 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The electronic and optical properties of two-dimensional layered materials allow the miniaturization of nanoelectronic and optoelectronic devices in a competitive manner. Even larger opportunities arise when two or more layers of different materials are combined. Here, we report on an ultrafast energy efficient strategy, using laser irradiation, which allows bulk synthesis of crystalline single-layered lead iodide in the cavities of carbon nanotubes by forming cylindrical van der Waals heterostructures. In contrast to the filling of van der Waals solids into carbon nanotubes by conventional thermal annealing, which favors the formation of inorganic nanowires, the present strategy is highly selective toward the growth of monolayers forming lead iodide nanotubes. The irradiated bulk material bearing the nanotubes reveals a decrease of the resistivity as well as a significant increase in the current flow upon illumination. Both effects are attributed to the presence of single-walled lead iodide nanotubes in the cavities of carbon nanotubes, which dominate the properties of the whole matrix. The present study brings in a simple, ultrafast and energy efficient strategy for the tailored synthesis of rolled-up single-layers of lead iodide (i.e., single-walled PbI2 nanotubes), which we believe could be expanded to other two-dimensional (2D) van der Waals solids. In fact, initial tests with ZnI2 already reveal the formation of single-walled ZnI2 nanotubes, thus proving the versatility of the approach. |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
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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 |
8 |
Open Access |
OpenAccess |
Notes |
; We acknowledge funding from MINECO (Spain), through MAT2017-86616-R, ENE2017-89210-C2-1-R, and “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0496, SEV-2013-0295), CERCA programme for funding ICN2 and support from AGAUR of Generalitat de Catalunya through the projects 2017 SGR 1086, 2017 SGR 581 and 2017 SGR 327. We thank Thomas Swan Co., Ltd., for supplying MWCNT Elicarb samples. D.K. acknowledges financial support from the Ministry of Education, Science, and Technological Development of the Republic of Serbia for postdoctoral research. We are grateful to R Rurali (ICMAB-CSIC) for providing the structural model of the PbI<INF>2</INF> nanotube employed for the schematic representation of PbI<INF>2</INF>@MVWCNT. ; |
Approved |
Most recent IF: 13.942 |
Call Number |
UA @ lucian @ c:irua:153169 |
Serial |
5127 |
Permanent link to this record |
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Author |
Vishwakarma, M.; Thota, N.; Karakulina, O.; Hadermann, J.; Mehta, B.R. |
Title |
Role of graphene inter layer on the formation of the MoS2 – CZTS interface during growth |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
(icc-2017) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
The growth of MoS2 layer near the Mo/CZTS interface during sulphurization process can have an impact on back contact cell parameters (series resistance and fill factor) depending upon the thickness or quality of MoS2. This study reports the dependence of the thickness of interfacial MoS2 layer on the growth of graphene at the interface between molybdenum back contact and deposited CZTS layer. The graphene layer reduces the accumulation of Zn/ZnS, Sn/SnO2 and formation of pores near the MoS2-CZTS interface. The use of graphene as interface layer can be potentially useful for improving the quality of Mo/MoS2/CZTS interface. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Amer inst physics |
Place of Publication |
Melville |
Editor |
|
Language |
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Wos |
000436313003046 |
Publication Date |
2018-05-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
1953 |
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
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ISSN |
978-0-7354-1648-2; 0094-243x; 0094-243x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
OpenAccess |
Notes |
; The authors acknowledge support provided by DST project. M.V. acknowledges IIT Delhi for MHRD fellowship. Prof. B. R. Mehta acknowledges the support of the Schlumberger chair professorship. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:153203 |
Serial |
5126 |
Permanent link to this record |
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|
|
Author |
Van der Donck, M.; Peeters, F.M. |
Title |
Rich many-body phase diagram of electrons and holes in doped monolayer transition metal dichalcogenides |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
11 |
Pages |
115432 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We use a variational technique to study the many-body phase diagram of electrons and holes in n-doped and p-doped monolayer transition metal dichalcogenides (TMDs). We find a total of four different phases. (i) A fully spin polarized and valley polarized ferromagnetic state. (ii) A state with no global spin polarization but with spin polarization in each valley separately, i.e., spin-valley locking. (iii) A state with spin polarization in one of the valleys and little to no spin polarization in the other valley. (iv) A paramagnetic state with no valley polarization. These phases are separated by first-order phase transitions and are determined by the particle density and the dielectric constant of the substrate. We find that in the presence of a perpendicular magnetic field the four different phases persist. In the case of n-doped MoS2, a fifth phase, which is completely valley polarized but not spin polarized, appears for magnetic fields larger than 7 T and for magnetic fields larger than 23 T completely replaces the second phase. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000445507000009 |
Publication Date |
2018-09-24 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:153622UA @ admin @ c:irua:153622 |
Serial |
5125 |
Permanent link to this record |
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Author |
Leus, K.; Folens, K.; Nicomel, N.R.; Perez, J.P.H.; Filippousi, M.; Meledina, M.; Dirtu, M.M.; Turner, S.; Van Tendeloo, G.; Garcia, Y.; Du Laing, G.; Van Der Voort, P. |
Title |
Removal of arsenic and mercury species from water by covalent triazine framework encapsulated \gamma-Fe2O3 nanoparticles |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
353 |
Issue |
353 |
Pages |
312-319 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The covalent triazine framework, CTF-1, served as host material for the in situ synthesis of Fe2O3 nanoparticles. The composite material consisted of 20 +/- 2 m% iron, mainly in gamma-Fe2O3 phase. The resulting gamma-Fe2O3@CTF-1 was examined for the adsorption of As-III, As-V and H-II from synthetic solutions and real surface-, ground- and wastewater. The material shows excellent removal efficiencies, independent from the presence of Ca2+, Mg2+ or natural organic matter and only limited dependency on the presence of phosphate ions. Its adsorption capacity towards arsenite (198.0 mg g(-1)), arsenate (102.3 mg g(-1)) and divalent mercury (165.8 mg g(-1)) belongs amongst the best-known adsorbents, including many other iron-based materials. Regeneration of the adsorbent can be achieved for use over multiple cycles without a decrease in performance by elution at 70 degrees C with 0.1 M NaOH, followed by a stirring step in a 5 m% H2O2 solution for As or 0.1 M thiourea and 0.001 M HCl for Hg. In highly contaminated water (100 mu gL(-1)), the adsorbent polishes the water quality to well below the current WHO limits. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000438002800035 |
Publication Date |
2018-04-16 |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
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ISSN |
0304-3894 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
22 |
Open Access |
OpenAccess |
Notes |
; Karen Leus acknowledges financial support from Ghent University. Nina Ricci Nicomel and Jeffrey Paulo H. Perez thank the funding of the VLIR-UOS. Marinela M. Dirtu acknowledges F.R.S.-FNRS for a Charge de recherches position. Stuart Turner gratefully acknowledges the FWO Vlaanderen for a post-doctoral scholarship. The Titan microscope used for this investigation was partially funded by the Hercules foundation of the Flemish government. This work was supported by the Belgian IAP-PAI network. ; |
Approved |
Most recent IF: 6.065 |
Call Number |
UA @ lucian @ c:irua:152430 |
Serial |
5124 |
Permanent link to this record |
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Author |
Cherigui, E.A.M.; Şentosun, K.; Mamme, M.H.; Lukaczynska, M.; Terryn, H.; Bals, S.; Ustarroz, J. |
Title |
On the control and effect of water content during the electrodeposition of Ni nanostructures from deep eutectic solvents |
Type |
A1 Journal article |
Year |
2018 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
122 |
Issue |
122 |
Pages |
23129-23142 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The electrodeposition of nickel nanostructures on glassy carbon was investigated in 1:2 choline chloride urea deep eutectic solvent (DES) containing different amounts of water. By combining electrochemical techniques, with ex situ field emission scanning electron microscopy, high-angle annular dark field scanning transmission electron microscopy, and energy-dispersive X-ray spectroscopy, the effect of water content on the electrochemical processes occurring during nickel deposition was better understood. At highly negative potentials and depending on water content, Ni growth is halted due to water splitting and formation of a mixed layer of Ni/NiOx(OH)(2(1-x)(ads)). Moreover, under certain conditions, the DES components can also be (electro)chemically reduced at the electrode surface, blocking further three-dimensional growth of the Ni NPs. Hence, a two-dimensional crystalline Ni-containing network can be formed in the interparticle region. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000447471700038 |
Publication Date |
2018-09-18 |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
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ISSN |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
27 |
Open Access |
OpenAccess |
Notes |
; E.A.M.C. and M.H.M. acknowledge funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, research project G019014N). S.B. acknowledges funding from the European Research Council (Starting Grant No. COLOURATOMS 335078). Finally, J.U. acknowledges funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, postdoctoral grant 12I7816N). ; ecas_sara |
Approved |
Most recent IF: 4.536 |
Call Number |
UA @ lucian @ c:irua:154731 |
Serial |
5121 |
Permanent link to this record |
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Author |
Vodolazov, D.Y.; Berdiyorov, G.; Peeters, F.M. |
Title |
Negative magnetoresistance in thin superconducting films with parallel orientation of current and magnetic field |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
552 |
Issue |
552 |
Pages |
64-66 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Thin superconducting films can exhibit negative magnetoresistance when an in-plane external magnetic field is aligned parallel with the transport current. We explain this effect as due to appearance of parallel vortices in the plain of the film at the first critical magnetic field H-c1 which leads to an enhancement of the superconducting properties and impedes the motion of the current induced perpendicular vortices. Our theoretical results are based on a numerical solution of the time-dependent and stationary 3D Ginzburg-Landau equations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000440786600012 |
Publication Date |
2018-07-20 |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
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ISSN |
0921-4534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
6 |
Open Access |
|
Notes |
; The work is supported by the Russian Science Foundation Project No. 17-72-30036 and the Malthusian programme of the Flemish government. ; |
Approved |
Most recent IF: 1.404 |
Call Number |
UA @ lucian @ c:irua:153067UA @ admin @ c:irua:153067 |
Serial |
5117 |
Permanent link to this record |
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Author |
Zarenia, M.; Hamilton, A.R.; Peeters, F.M.; Neilson, D. |
Title |
Multiband mechanism for the sign reversal of Coulomb drag observed in double bilayer graphene heterostructures |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
121 |
Issue |
3 |
Pages |
036601 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Coupled 2D sheets of electrons and holes are predicted to support novel quantum phases. Two experiments of Coulomb drag in electron-hole (e-h) double bilayer graphene (DBLG) have reported an unexplained and puzzling sign reversal of the drag signal. However, we show that this effect is due to the multiband character of DBLG. Our multiband Fermi liquid theory produces excellent agreement and captures the key features of the experimental drag resistance for all temperatures. This demonstrates the importance of multiband effects in DBLG: they have a strong effect not only on superfluidity, but also on the drag. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000438883600008 |
Publication Date |
2018-07-18 |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
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ISSN |
0031-9007 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
7 |
Open Access |
|
Notes |
; We are grateful to Cory Dean, Emanuel Tutuc, and their research groups for discussing details of their experiments with us. This work was partially supported by the Flemish Science Foundation (FWO-Vl), the Methusalem program of the Flemish government, and the Australian Government through the Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies (Project No. CE170100039). D. N. acknowledges support from the University of Camerino FAR project CESEMN. ; |
Approved |
Most recent IF: 8.462 |
Call Number |
UA @ lucian @ c:irua:152416UA @ admin @ c:irua:152416 |
Serial |
5116 |
Permanent link to this record |
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Author |
Kandemir, A.; Peeters, F.M.; Sahin, H. |
Title |
Monitoring the effect of asymmetrical vertical strain on Janus single layers of MoSSe via spectrum |
Type |
A1 Journal article |
Year |
2018 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
149 |
Issue |
8 |
Pages |
084707 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using first principles calculations, we study the structural and phononic properties of the recently synthesized Janus type single layers of molybdenum dichalcogenides. The Janus MoSSe single layer possesses 2H crystal structure with two different chalcogenide sides that lead to out-of-plane anisotropy. By virtue of the asymmetric structure of the ultra-thin Janus type crystal, we induced the out-of-plane anisotropy to show the distinctive vertical pressure effect on the vibrational properties of the Janus material. It is proposed that for the corresponding Raman active optical mode of the Janus structure, the phase modulation and the magnitude ratio of the strained atom and its first neighbor atom adjust the distinctive change in the eigen-frequencies and Raman activity. Moreover, a strong variation in the Raman activity of the Janus structure is obtained under bivertical and univertical strains. Not only eigen-frequency shifts but also Raman activities of the optical modes of the Janus structure exhibit distinguishable features. This study reveals that the vertical anisotropic feature of the Janus structure under Raman measurement allows us to distinguish which side of the Janus crystal interacts with the externals (substrate, functional adlayers, or dopants). Published by AIP Publishing. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
|
Wos |
000444035800044 |
Publication Date |
2018-08-30 |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0021-9606 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.965 |
Times cited |
11 |
Open Access |
|
Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from TUBITAK under Project No. 117F095. F.M.P. was supported by the FLAG-ERA-TRANS<INF>2D</INF>TMD. ; |
Approved |
Most recent IF: 2.965 |
Call Number |
UA @ lucian @ c:irua:153711UA @ admin @ c:irua:153711 |
Serial |
5115 |
Permanent link to this record |
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|
|
Author |
Van Pottelberge, R.; Zarenia, M.; Peeters, F.M. |
Title |
Magnetic field dependence of atomic collapse in bilayer graphene |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
11 |
Pages |
115406 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The spectrum of a Coulomb impurity in bilayer graphene is investigated as function of the strength of a perpendicular magnetic field for different values of the angular quantum number m and for different values of the gate voltage. We point out fundamental differences between the results from the two-band and four-band model. The supercritical instability and fall-to-center phenomena are investigated in the presence of a magnetic field. We find that in the four-band model the fall-to-center phenomenon occurs as in monolayer graphene, while this is not the case in the two-band model. We find that in a magnetic field the supercritical instability manifests itself as a series of anticrossings in the hole part of the spectrum for states coming from the low-energy band. However, we also find very distinct anticrossings in the electron part of the spectrum that continue into the hole part, which are related to the higher energy band of the four-band model. At these anticrossings, we find a very sharp peak in the probability density close to the impurity, reminiscent for the fall-to-center phenomenon. In this paper, these peculiar and interesting effects are studied for different magnetic field, interlayer coupling, and bias potential strengths. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000443671900010 |
Publication Date |
2018-09-04 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
|
Notes |
; We thank Matthias Van der Donck and Ben Van Duppen for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:153654UA @ admin @ c:irua:153654 |
Serial |
5113 |
Permanent link to this record |
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|
|
Author |
Filez, M.; Poelman, H.; Redekop, E.A.; Galvita, V.V.; Alexopoulos, K.; Meledina, M.; Ramachandran, R.K.; Dendooven, J.; Detavernier, C.; Van Tendeloo, G.; Safonova, O.V.; Nachtegaal, M.; Weckhuysen, B.M.; Marin, G.B. |
Title |
Kinetics of lifetime changes in bimetallic nanocatalysts revealed by quick X-ray absorption spectroscopy |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
57 |
Issue |
38 |
Pages |
12430-12434 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Alloyed metal nanocatalysts are of environmental and economic importance in a plethora of chemical technologies. During the catalyst lifetime, supported alloy nanoparticles undergo dynamic changes which are well-recognized but still poorly understood. High-temperature O-2-H-2 redox cycling was applied to mimic the lifetime changes in model Pt13In9 nanocatalysts, while monitoring the induced changes by insitu quick X-ray absorption spectroscopy with one-second resolution. The different reaction steps involved in repeated Pt13In9 segregation-alloying are identified and kinetically characterized at the single-cycle level. Over longer time scales, sintering phenomena are substantiated and the intraparticle structure is revealed throughout the catalyst lifetime. The insitu time-resolved observation of the dynamic habits of alloyed nanoparticles and their kinetic description can impact catalysis and other fields involving (bi)metallic nanoalloys. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
|
Wos |
000444225100038 |
Publication Date |
2018-08-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
1433-7851; 0570-0833 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.994 |
Times cited |
4 |
Open Access |
OpenAccess |
Notes |
; M.F. acknowledges a European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement (No. 748563). E.A.R acknowledges the Marie Curie International Incoming Fellowship granted by the European Commission (No. 301703). This work was supported by the Fund for Scientific Research Flanders (G.0209.11), the “Long Term Structural Methusalem Funding by the Flemish Government”. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7 /2007-2013) under grant agreement No. 312284 (CALIPSO). We thanks the Swiss Light Source for providing beamtime at the SuperXAS beamline. ; |
Approved |
Most recent IF: 11.994 |
Call Number |
UA @ lucian @ c:irua:153633 |
Serial |
5111 |
Permanent link to this record |
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|
|
Author |
Van der Donck, M.; Peeters, F.M. |
Title |
Interlayer excitons in transition metal dichalcogenide heterostructures |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
11 |
Pages |
115104 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from the single-particle Dirac Hamiltonian for charge carriers in monolayer transition metal dichalcogenides (TMDs), we construct a four-band Hamiltonian describing interlayer excitons consisting of an electron in one TMD layer and a hole in the other TMD layer. An expression for the electron-hole interaction potential is derived, taking into account the effect of the dielectric environment above, below, and between the two TMD layers as well as polarization effects in the transition metal layer and in the chalcogen layers of the TMD layers. We calculate the interlayer exciton binding energy and average in-plane interparticle distance for different TMD heterostructures. The effect of different dielectric environments on the exciton binding energy is investigated and a remarkable dependence on the dielectric constant of the barrier between the two layers is found, resulting from competing effects as a function of the in-plane and out-of-plane dielectric constants of the barrier. The polarization effects in the chalcogen layers, which in general reduce the exciton binding energy, can lead to an increase in binding energy in the presence of strong substrate effects by screening the substrate. The excitonic absorbance spectrum is calculated and we show that the interlayer exciton peak depends linearly on a perpendicular electric field, which agrees with recent experimental results. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000443671900004 |
Publication Date |
2018-09-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
41 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:153653UA @ admin @ c:irua:153653 |
Serial |
5110 |
Permanent link to this record |
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|
|
Author |
Tessier, M.D.; Baquero, E.A.; Dupont, D.; Grigel, V.; Bladt, E.; Bals, S.; Coppel, Y.; Hens, Z.; Nayral, C.; Delpech, F. |
Title |
Interfacial oxidation and photoluminescence of InP-Based core/shell quantum dots |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
30 |
Issue |
30 |
Pages |
6877-6883 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Indium phosphide colloidal quantum dots (QDs) are emerging as an efficient cadmium-free alternative for optoelectronic applications. Recently, syntheses based on easy-to-implement aminophosphine precursors have been developed. We show by solid-state nuclear magnetic resonance spectroscopy that this new approach allows oxide-free indium phosphide core or core/shell quantum dots to be made. Importantly, the oxide-free core/shell interface does not help in achieving higher luminescence efficiencies. We demonstrate that in the case of InP/ZnS and InP/ZnSe QDs, a more pronounced oxidation concurs with a higher photoluminescence efficiency. This study suggests that a II-VI shell on a III-V core generates an interface prone to defects. The most efficient InP/ZnS or InP/ZnSe QDs are therefore made with an oxide buffer layer between the core and the shell: it passivates these interface defects but also results in a somewhat broader emission line width. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
|
Language |
|
Wos |
000447237800031 |
Publication Date |
2018-09-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
74 |
Open Access |
OpenAccess |
Notes |
; The authors thank L. Biadala and C. Delerue for fruitful discussion. Z.H. acknowledges support by the European Commission via the Marie-Sklodowska Curie action Phonsi (H2020-MSCA-ITN-642656), by Research Foundation Flanders (Project 17006602), and by Ghent University (GOA No. 01G01513). Z.H., M.D.T., and D.D. acknowledge the Strategisch Initiatief Materialen in Vlaanderen of Agentschap Innoveren en Ondernemen (SIM VLAIO), vzw (SBO-QDOCCO, ICON-QUALIDI). This work was supported by the Universite Paul Sabatier, the Region Midi-Pyrenees, the CNRS, the Institut National des Sciences Appliquees of Toulouse, and the Agence Nationale pour la Recherche (Project ANR-13-IS10-0004-01). E.A.B. is grateful to Marie Curie Actions and Campus France for a PRESTIGE postdoc fellowship (FP7 /2007-2013) under REA Grant Agreement PCOFUND-GA-2013-609102. E.B. acknowledges financial support from Research Foundation Flanders (FWO). ; |
Approved |
Most recent IF: 9.466 |
Call Number |
UA @ lucian @ c:irua:154732UA @ admin @ c:irua:154732 |
Serial |
5109 |
Permanent link to this record |
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|
Author |
Pahlke, P.; Sieger, M.; Ottolinger, R.; Lao, M.; Eisterer, M.; Meledin, A.; Van Tendeloo, G.; Haenisch, J.; Holzapfel, B.; Schultz, L.; Nielsch, K.; Huehne, R. |
Title |
Influence of artificial pinning centers on structural and superconducting properties of thick YBCO films on ABAD-YSZ templates |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
31 |
Issue |
4 |
Pages |
044007 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Recent efforts in the development of YBa2Cu3O7-x (YBCO) coated conductors are devoted to the increase of the critical current I-c in magnetic fields. This is typically realized by growing thicker YBCO layers as well as by the incorporation of artificial pinning centers. We studied the growth of doped YBCO layers with a thickness of up to 7 mu m using pulsed laser deposition with a growth rate of about 1.2 nm s(-1). Industrially fabricated ion-beam textured YSZ templates based on metal tapes were used as substrates for this study. The incorporation of BaHfO3 (BHO) or Ba2Y(Nb0.5Ta0.5)O-6 (BYNTO) secondary phase additions leads to a denser microstructure compared to undoped films. A purely c-axis-oriented YBCO growth is preserved up to a thickness of about 4 mu m, whereas misoriented texture components were observed in thicker films. The critical temperature is slightly reduced compared to undoped films and independent of film thickness. The critical current density J(c) of the BHO- and BYNTO-doped YBCO layers is lower at 77 K and self-field compared to pure YBCO layers; however, I-c increases up to a thickness of 5 mu m. A comparison between films with a thickness of 1.3 mu m revealed that the anisotropy of the critical current density J(c)(theta) strongly depends on the incorporated pinning centers. Whereas BHO nanorods lead to a strong B vertical bar vertical bar c-axis peak, the overall anisotropy is significantly reduced by the incorporation of BYNTO forming a mixture of short c-axis-oriented nanorods and small (a-b)-oriented platelets. As a result, the J(c) values of the doped films outperform the undoped samples at higher fields and lower temperatures for most magnetic field directions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000442196400001 |
Publication Date |
2018-02-15 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0953-2048 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
9 |
Open Access |
OpenAccess |
Notes |
; The authors acknowledge financial support from EURO-TAPES, a collaborative project funded by the European Union's Seventh Framework Programme (FP7/ 2007-2013) under Grant Agreement no. 280432. We thank A Usoskin (Bruker HTS GmbH, Germany) for the provision of buffered templates, and M Bianchetti, A Kursumovic and J L Mac-Manus-Driscoll (University of Cambridge, UK) for the supply of BYNTO targets. The authors also gratefully acknowledge the technical assistance of J Scheiter, M Kuhnel, U Besold (IFW) and R Nast (KIT). ; |
Approved |
Most recent IF: 2.878 |
Call Number |
UA @ lucian @ c:irua:153775 |
Serial |
5108 |
Permanent link to this record |
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|
Author |
Wu, S.-M.; Liu, X.-L.; Lian, X.-L.; Tian, G.; Janiak, C.; Zhang, Y.-X.; Lu, Y.; Yu, H.-Z.; Hu, J.; Wei, H.; Zhao, H.; Chang, G.-G.; Van Tendeloo, G.; Wang, L.-Y.; Yang, X.-Y.; Su, B.-L. |
Title |
Homojunction of oxygen and titanium vacancies and its interfacial n-p effect |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
30 |
Issue |
32 |
Pages |
1802173 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The homojunction of oxygen/metal vacancies and its interfacial n-p effect on the physiochemical properties are rarely reported. Interfacial n-p homojunctions of TiO2 are fabricated by directly decorating interfacial p-type titanium-defected TiO2 around n-type oxygen-defected TiO2 nanocrystals in amorphous-anatase homogeneous nanostructures. Experimental measurements and theoretical calculations on the cell lattice parameters show that the homojunction of oxygen and titanium vacancies changes the charge density of TiO2; a strong EPR signal caused by oxygen vacancies and an unreported strong titanium vacancies signal of 2D H-1 TQ-SQ MAS NMR are present. Amorphous-anatase TiO2 shows significant performance regarding the photogeneration current, photocatalysis, and energy storage, owing to interfacial n-type to p-type conductivity with high charge mobility and less structural confinement of amorphous clusters. A new homojunction of oxygen and titanium vacancies concept, characteristics, and mechanism are proposed at an atomic-/nanoscale to clarify the generation of oxygen vacancies and titanium vacancies as well as the interface electron transfer. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000440813300022 |
Publication Date |
2018-06-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
39 |
Open Access |
Not_Open_Access |
Notes |
; This work was supported by National Key R&D Program of China (2017YFC1103800), National SFC (U1662134, U1663225, 51472190, 51611530672, 21711530705, 51503166, 21706199), ISTCP (2015DFE52870), PCSIRT (IRT_15R52), HPNSF (2016CFA033, 2017CFB487), and SKLPPC (PPC2016007). ; |
Approved |
Most recent IF: 19.791 |
Call Number |
UA @ lucian @ c:irua:153106 |
Serial |
5105 |
Permanent link to this record |
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|
|
Author |
Aierken, Y.; Leenaerts, O.; Peeters, F.M. |
Title |
First-principles study of the stability and edge stress of nitrogen-decorated graphene nanoribbons |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
97 |
Issue |
23 |
Pages |
235436 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Edge functionalization of graphene nanoribbons with nitrogen atoms for various adatom configurations at armchair and zigzag edges are investigated. We provide comprehensive information on the electronic and magnetic properties and investigate the stability of the various systems. Two types of rippling of the nanoribbons, namely edge and bulk rippling depending on the sign of edge stress induced at the edge, are found. They are found to play the decisive role for the stability of the structures. We also propose a type of edge decoration in which every third nitrogen adatom at the zigzag edges is replaced by an oxygen atom. In this way, the electron count is compatible with a full aromatic structure, leading to additional stability and a disappearance of magnetism that is usually associated with zigzag nanoribbons. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000436192300006 |
Publication Date |
2018-06-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
1 |
Open Access |
|
Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:152478UA @ admin @ c:irua:152478 |
Serial |
5104 |
Permanent link to this record |
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|
Author |
Tang, Y.; Hunter, E.C.; Battle, P.D.; Hendrickx, M.; Hadermann, J.; Cadogan, J.M. |
Title |
Ferrimagnetism as a consequence of unusual cation ordering in the Perovskite SrLa2FeCoSbO9 |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
57 |
Issue |
12 |
Pages |
7438-7445 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A polycrystalline sample of SrLa2FeCoSbO9 has been prepared in a solid-state reaction and studied by a combination of electron microscopy, magnetometry, Mossbauer spectroscopy, X-ray diffraction, and neutron diffraction. The compound adopts a monoclinic (space group P2(1)/n; a = 5.6218(6), b = 5.6221(6), c = 7.9440(8) angstrom, beta = 90.050(7)degrees at 300 K) perovskite-like crystal structure with two crystallographically distinct six-coordinate sites. One of these sites is occupied by 2/3 Co-2(+),1/3 Fe3+ and the other by 2/3 Sb5+, 1/3 Fe3+. This pattern of cation ordering results in a transition to a ferrimagnetic phase at 215 K. The magnetic moments on nearest-neighbor, six-coordinate cations align in an antiparallel manner, and the presence of diamagnetic Sb5+ on only one of the two sites results in a nonzero remanent magnetization of similar to 1 mu(B) per formula unit at 5 K. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
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Wos |
000436023800073 |
Publication Date |
2018-05-29 |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0020-1669 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
6 |
Open Access |
Not_Open_Access |
Notes |
; PDB, ECH, and JH acknowledge support from EPSRC under grant EP/M0189954/1. We would like to thank the STFC for the award of beamtime at the ISIS Neutron and Muon Source (RB 1610100), and we thank Dr. I. da Silva for the assistance provided. We also thank Dr. R Paria Sena for help with the HAADF-STEM and STEM-EDX experiments. ; |
Approved |
Most recent IF: 4.857 |
Call Number |
UA @ lucian @ c:irua:152485 |
Serial |
5103 |
Permanent link to this record |
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|
Author |
Theofanidis, S.A.; Galvita, V.V.; Poelman, H.; Dharanipragada, N.V.R.A.; Longo, A.; Meledina, M.; Van Tendeloo, G.; Detavernier, C.; Marin, G.B. |
Title |
Fe-containing magnesium aluminate support for stability and carbon control during methane reforming |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
Volume |
8 |
Issue |
7 |
Pages |
5983-5995 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report a MgFexAl2-xO4 synthetic spinel, where x varies from 0 to 0.26, as support for Ni-based catalysts, offering stability and carbon control under various conditions of methane reforming. By incorporation of Fe into a magnesium aluminate spine!, a support is created with redox functionality and high thermal stability, as concluded from temporal analysis of products (TAP) experiments and redox cycling, respectively. A diffusion coefficient of 3 x 10(-17) m(2) s(-1) was estimated for lattice oxygen at 993 K from TAP experiments. X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) modeling identified that the incorporation of iron occurs as Fe3+ in the octahedral sites of the spinel lattice, replacing aluminum. Simulation of the X-ray absorption near edge structure (XANES) spectrum of the reduced support showed that 60 +/- 10% of iron was reduced from 3+ to 2+ at 1073 K, while there was no formation of metallic iron. A series of Ni/MgFexAl2-xO4 catalysts, where x varies from 0 to 0.26, was synthesized and reduced, yielding a supported Ni-Fe alloy. The evolution of the catalyst structure during H-2 temperature-programmed reduction (TPR) and CO2 temperature-programmed oxidation (TPO) was examined using time-resolved in situ XRD and XANES. During reforming, iron in both the support and alloy keeps control of carbon accumulation, as confirmed by O-2-TPO on the spent catalysts. By fine tuning the amount of Fe in MgFexAl2-xO4, a supported alloy was obtained with a Ni/Fe molar ratio of similar to 10, which was active for reforming and stable. By comparison of the performance of Ni-based catalysts with Fe either incorporated into or deposited onto the support, the location of Fe within the support proved crucial for the stability and carbon mitigation under reforming conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000438475100034 |
Publication Date |
2018-05-22 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.614 |
Times cited |
18 |
Open Access |
OpenAccess |
Notes |
; This work was supported by the FAST industrialization by Catalyst Research and Development (FASTCARD) project, which is a Large Scale Collaborative Project supported by the European Commission in the 7th Framework Programme (GA no 604277), the “Long Term Structural Methusalem Funding by the Flemish Government”, the Interuniversity Attraction Poles Programme, IAP7/5, Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of travel costs and beam time at the DUBBLE beamline of the ESRF. The authors acknowledge the assistance from the DUBBLE (ESRF, XAS campaign 26-01-1048) and ROCK staff (SOLEIL, proposal 201502561). The authors equally acknowledge support from a public grant overseen by the French National Research Agency (ANR) as part of the “Investissements d'Avenir” program (reference: ANR-10-EQPX-45) for the ROCK beamline and from Lukas Buelens and Rakesh Batchu (Laboratory for Chemical Technology, Ghent University) for the STEM measurements and TAP experiments, respectively. ; |
Approved |
Most recent IF: 10.614 |
Call Number |
UA @ lucian @ c:irua:153178 |
Serial |
5102 |
Permanent link to this record |
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|
|
Author |
Aydin, H.; Bacaksiz, C.; Yagmurcukardes, N.; Karakaya, C.; Mermer, O.; Can, M.; Senger, R.T.; Sahin, H.; Selamet, Y. |
Title |
Experimental and computational investigation of graphene/SAMs/n-Si Schottky diodes |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Applied Surface Science |
Abbreviated Journal |
Appl Surf Sci |
Volume |
428 |
Issue |
428 |
Pages |
1010-1017 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have investigated the effect of two different self-assembled monolayers (SAMs) on electrical characteristics of bilayer graphene (BLG)/n-Si Schottky diodes. Novel 4“bis(diphenylamino)-1, 1':3”-terpheny1-5' carboxylic acids (TPA) and 4,4-di-9H-carbazol-9-y1-1,1':3'1'-terpheny1-5' carboxylic acid (CAR) aromatic SAMs have been used to modify n-Si surfaces. Cyclic voltammetry (CV) and Kelvin probe force microscopy (KPFM) results have been evaluated to verify the modification of n-Si surface. The current-voltage (I-V) characteristics of bare and SAMs modified devices show rectification behaviour verifying a Schottky junction at the interface. The ideality factors (n) from ln(I)-V dependences were determined as 2.13,1.96 and 2.07 for BLG/n-Si, BLG/TPA/n-Si and BLG/CAR/n-Si Schottky diodes, respectively. In addition, Schottky barrier height (SBH) and series resistance (Rs) of SAMs modified diodes were decreased compared to bare diode due to the formation of a compatible interface between graphene and Si as well as n-n interaction between aromatic SAMs and graphene. The CAR-based device exhibits better diode characteristic compared to the TPA-based device. Computational simulations show that the BLG/CAR system exhibits smaller energy-level-differences than the BLG/TPA, which supports the experimental findings of a lower Schottky barrier and series resistance in BLG/CAR diode. (C) 2017 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000415227000128 |
Publication Date |
2017-09-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0169-4332 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.387 |
Times cited |
2 |
Open Access |
|
Notes |
; This work was supported by TUBITAK (The Scientific and Technical Research Council of Turkey) with project number 112T946. We also thank AQuReC (Applied Quantum Research Center) for Raman measurements. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Bilim Akademisi The Science Academy, Turkey under the BAGEP program. ; |
Approved |
Most recent IF: 3.387 |
Call Number |
UA @ lucian @ c:irua:154608UA @ admin @ c:irua:154608 |
Serial |
5101 |
Permanent link to this record |
|
|
|
Author |
Brodu, A.; Ballottin, M.V.; Buhot, J.; van Harten, E.J.; Dupont, D.; La Porta, A.; Prins, P.T.; Tessier, M.D.; Versteegh, M.A.M.; Zwiller, V.; Bals, S.; Hens, Z.; Rabouw, F.T.; Christianen, P.C.M.; de Donega, C.M.; Vanmaekelbergh, D. |
Title |
Exciton Fine Structure and Lattice Dynamics in InP/ZnSe Core/Shell Quantum Dots |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS Photonics |
Abbreviated Journal |
Acs Photonics |
Volume |
5 |
Issue |
5 |
Pages |
3353-3362 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Nanocrystalline InP quantum dots (QDs) hold promise for heavy-metal-free optoelectronic applications due to their bright and size tunable emission in the visible range. Photochemical stability and high photoluminescence (PL) quantum yield are obtained by a diversity of epitaxial shells around the InP core. To understand and optimize the emission line shapes, the exciton fine structure of InP core/shell QD systems needs be investigated. Here, we study the exciton fine structure of InP/ZnSe core/shell QDs with core diameters ranging from 2.9 to 3.6 nm (PL peak from 2.3 to 1.95 eV at 4 K). PL decay measurements as a function of temperature in the 10 mK to 300 K range show that the lowest exciton fine structure state is a dark state, from which radiative recombination is assisted by coupling to confined acoustic phonons with energies ranging from 4 to 7 meV, depending on the core diameter. Circularly polarized fluorescence line-narrowing (FLN) spectroscopy at 4 K under high magnetic fields (up to 30 T) demonstrates that radiative recombination from the dark F = +/- 2 state involves acoustic and optical phonons, from both the InP core and the ZnSe shell. Our data indicate that the highest intensity FLN peak is an acoustic phonon replica rather than a zero-phonon line, implying that the energy separation observed between the F = +/- 1 state and the highest intensity peak in the FLN spectra (6 to 16 meV, depending on the InP core size) is larger than the splitting between the dark and bright fine structure exciton 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 |
000442185900049 |
Publication Date |
2018-07-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2330-4022 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.756 |
Times cited |
40 |
Open Access |
OpenAccess |
Notes |
; We acknowledge the support of the HFML-RU/FOM, member of the European Magnetic Field Laboratory (EMFL). D.V. and Z.H. acknowledge support by the European Commission via the Marie-Sklodowska Curie action Phonsi (H2020-MSCA-ITN-642656) and the Marie Sklodowska-Curie Action Compass (H2020 MSCA-RISE-691185). Z.H. acknowledges the Research Foundation Flanders (project 17006602) and Ghent University (GOA no. 01G01513). Z.H. and S.B. acknowledge SIM vzw (SBO-QDOCCO). F.T.R. acknowledges financial support from The Netherlands Organisation for Scientific Research NWO (Gravitation program Multiscale Catalytic Energy Conversion and VENI grant number 722.017.002). This work was also supported by the Dutch NWO-Physics Program DDC13, ERC Advanced Grant 692691 “First step”, and ERC Starting Grant 335078 “COLOURATOM”. ; ecas_sara |
Approved |
Most recent IF: 6.756 |
Call Number |
UA @ lucian @ c:irua:153753UA @ admin @ c:irua:153753 |
Serial |
5100 |
Permanent link to this record |
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|
|
Author |
Beckers, A.; Thewissen, M.; Sorée, B. |
Title |
Energy filtering in silicon nanowires and nanosheets using a geometric superlattice and its use for steep-slope transistors |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
124 |
Issue |
14 |
Pages |
144304 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
This paper investigates energy filtering in silicon nanowires and nanosheets by resonant electron tunneling through a geometric superlattice. A geometric superlattice is any kind of periodic geometric feature along the transport direction of the nanowire or nanosheet. Multivalley quantum-transport simulations are used to demonstrate the manifestation of minibands and minibandgaps in the transmission spectra of such a superlattice. We find that the presence of different valleys in the conduction band of silicon favors a nanowire with a rectangular cross section for effective energy filtering. The obtained energy filter can consequently be used in the source extension of a field-effect transistor to prevent high-energy electrons from contributing to the leakage current. Self-consistent Schrodinger-Poisson simulations in the ballistic limit show minimum subthreshold swings of 6 mV/decade for geometric superlattices with indentations. The obtained theoretical performance metrics for the simulated devices are compared with conventional III-V superlatticeFETs and TunnelFETs. The adaptation of the quantum transmitting boundary method to the finite-element simulation of 3-D structures with anisotropic effective mass is presented in Appendixes A and B. Our results bare relevance in the search for steep-slope transistor alternatives which are compatible with the silicon industry and can overcome the power-consumption bottleneck inherent to standard CMOS technologies. Published by AIP Publishing. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000447148100011 |
Publication Date |
2018-10-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ lucian @ c:irua:154729UA @ admin @ c:irua:154729 |
Serial |
5099 |
Permanent link to this record |
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Author |
Ren, Z.; Wu, M.; Chen, X.; Li, W.; Li, M.; Wang, F.; Tian, H.; Chen, J.; Xie, Y.; Mai, J.; Li, X.; Lu, X.; Lu, Y.; Zhang, H.; Van Tendeloo, G.; Zhang, Z.; Han, G. |
Title |
Electrostatic force-driven oxide heteroepitaxy for interface control |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
30 |
Issue |
38 |
Pages |
1707017 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Oxide heterostructure interfaces create a platform to induce intriguing electric and magnetic functionalities for possible future devices. A general approach to control growth and interface structure of oxide heterostructures will offer a great opportunity for understanding and manipulating the functionalities. Here, it is reported that an electrostatic force, originating from a polar ferroelectric surface, can be used to drive oxide heteroepitaxy, giving rise to an atomically sharp and coherent interface by using a low-temperature solution method. These heterostructures adopt a fascinating selective growth, and show a saturation thickness and the reconstructed interface with concentrated charges accumulation. The ferroelectric polarization screening, developing from a solid-liquid interface to the heterostructure interface, is decisive for the specific growth. At the interface, a charge transfer and accumulation take place for electrical compensation. The facile approach presented here can be extremely useful for controlling oxide heteroepitaxy and producing intriguing interface functionality via electrostatic engineering. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000444671900002 |
Publication Date |
2018-08-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
4 |
Open Access |
Not_Open_Access |
Notes |
; Z.H.R., M.J.W., and X.C. contributed equally to this work. This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 51232006, 51472218, 11474249, 61574123, 11374009, and 11234011), the National 973 Program of China (Grant No. 2015CB654901), National Young 1000 Talents Program of China, the Fundamental Research Funds for the Central Universities (Grant No. 2017FZA4008), and the 111 Project under Grant No. B16042. J.M. and X.L. gratefully thank the beam time and technical supports provided by 23A SWAXS beamline at NSRRC, Hsinchu. ; |
Approved |
Most recent IF: 19.791 |
Call Number |
UA @ lucian @ c:irua:153628 |
Serial |
5098 |
Permanent link to this record |
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Author |
Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. |
Title |
Electronic and vibrational properties of PbI2: From bulk to monolayer |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
8 |
Pages |
085431 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using first-principles calculations, we study the dependence of the electronic and vibrational properties of multilayered PbI2 crystals on the number of layers and focus on the electronic-band structure and the Raman spectrum. Electronic-band structure calculations reveal that the direct or indirect semiconducting behavior of PbI2 is strongly influenced by the number of layers. We find that at 3L thickness there is a direct-to-indirect band gap transition (from bulk-to-monolayer). It is shown that in the Raman spectrum two prominent peaks, A(1g) and E-g, exhibit phonon hardening with an increasing number of layers due to the interlayer van der Waals interaction. Moreover, the Raman activity of the A(1g) mode significantly increases with an increasing number of layers due to the enhanced out-of-plane dielectric constant in the few-layer case. We further characterize rigid-layer vibrations of low-frequency interlayer shear (C) and breathing (LB) modes in few-layer PbI2. A reduced monatomic (linear) chain model (LCM) provides a fairly accurate picture of the number of layers dependence of the low-frequency modes and it is shown also to be a powerful tool to study the interlayer coupling strength in layered PbI2. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000442667200008 |
Publication Date |
2018-08-24 |
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 ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
41 |
Open Access |
|
Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. Part of this work was supported by FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:153716UA @ admin @ c:irua:153716 |
Serial |
5097 |
Permanent link to this record |
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Author |
Zhou, K.-G.; Vasu, K.S.; Cherian, C.T.; Neek-Amal, M.; Zhang, J.C.; Ghorbanfekr-Kalashami, H.; Huang, K.; Marshall, O.P.; Kravets, V.G.; Abraham, J.; Su, Y.; Grigorenko, A.N.; Pratt, A.; Geim, A.K.; Peeters, F.M.; Novoselov, K.S.; Nair, R.R. |
Title |
Electrically controlled water permeation through graphene oxide membranes |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Nature |
Abbreviated Journal |
Nature |
Volume |
559 |
Issue |
7713 |
Pages |
236-+ |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Controlled transport of water molecules through membranes and capillaries is important in areas as diverse as water purification and healthcare technologies(1-7). Previous attempts to control water permeation through membranes (mainly polymeric ones) have concentrated on modulating the structure of the membrane and the physicochemical properties of its surface by varying the pH, temperature or ionic strength(3,8). Electrical control over water transport is an attractive alternative; however, theory and simulations(9-14) have often yielded conflicting results, from freezing of water molecules to melting of ice(14-16) under an applied electric field. Here we report electrically controlled water permeation through micrometre-thick graphene oxide membranes(17-21). Such membranes have previously been shown to exhibit ultrafast permeation of water(17,22) and molecular sieving properties(18,21), with the potential for industrial-scale production. To achieve electrical control over water permeation, we create conductive filaments in the graphene oxide membranes via controllable electrical breakdown. The electric field that concentrates around these current-carrying filaments ionizes water molecules inside graphene capillaries within the graphene oxide membranes, which impedes water transport. We thus demonstrate precise control of water permeation, from ultrafast permeation to complete blocking. Our work opens up an avenue for developing smart membrane technologies for artificial biological systems, tissue engineering and filtration. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
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Wos |
000438240900052 |
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 |
|
Series Issue |
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Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0028-0836 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
40.137 |
Times cited |
216 |
Open Access |
|
Notes |
; This work was supported by the Royal Society, Engineering and Physical Sciences Research Council, UK (EP/K016946/1, EP/N013670/1 and EP/P00119X/1), British Council (award reference number 279336045), European Research Council (contract 679689) and Lloyd's Register Foundation. We thank J. Waters for assisting with X-ray measurements and G. Yu for electrical measurements. ; |
Approved |
Most recent IF: 40.137 |
Call Number |
UA @ lucian @ c:irua:152420UA @ admin @ c:irua:152420 |
Serial |
5096 |
Permanent link to this record |
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Author |
Dong, H.M.; Xu, W.; Peeters, F.M. |
Title |
Electrical generation of terahertz blackbody radiation from graphene |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Optics express |
Abbreviated Journal |
Opt Express |
Volume |
26 |
Issue |
19 |
Pages |
24621-24626 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Recent experimental work on the application of graphene for novel illumination motivated us to present a theoretical study of the blackbody radiation emission from a freely suspended graphene driven by a dc electric field. Strong terahertz (THz) emission, with intensity up to mW/cm(2), can be generated with increasing electric field strength due to the heating of electrons in graphene. We show that the intensity of the THz emission generated electrically from graphene depends rather sensitively on the lattice temperature in relatively weak electric fields, whereas it is less sensitive to the lattice temperature in relative strong electric fields. Our study highlights the practical application of graphene as intense THz source where the radiation is generated electrically. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000444705000026 |
Publication Date |
2018-09-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
1094-4087 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.307 |
Times cited |
14 |
Open Access |
|
Notes |
; National Natural Science Foundation of China (NSFC) (11604380, 11574319); Center of Science and Technology of Hefei Academy of Science (2016FXZY002); Department of Science and Technology of Yunnan Province (2016FC001). ; |
Approved |
Most recent IF: 3.307 |
Call Number |
UA @ lucian @ c:irua:153632UA @ admin @ c:irua:153632 |
Serial |
5095 |
Permanent link to this record |
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Author |
Van Pottelberge, R.; Van Duppen, B.; Peeters, F.M. |
Title |
Electrical dipole on gapped graphene : bound states and atomic collapse |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
16 |
Pages |
165420 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the energy spectrum, wave functions, and local density of states of an electrical dipole placed on a sheet of gapped graphene as function of the charge strength Z alpha for different sizes of the dipole and for different regularization parameters. The dipole is modeled as consisting of a positive and negative charge. Bound states are found within the gap region with some energy levels that anticross and others that cross as function of the impurity strength Z alpha. The anticrossings are more pronounced and move to higher charges Z alpha when the length of the dipole decreases. These energy levels turn into atomic collapse states when they enter the positive (or negative) energy continuum. A smooth transition from the single-impurity behavior to the dipole one is observed: The states diving towards the continuum in the single-impurity case are gradually replaced by a series of anticrossings that represent a continuation of the diving states in the single-impurity case. By studying the local density of states at the edge of the dipole we show how the series of anticrossings persist in the positive and negative continuum. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000447302700010 |
Publication Date |
2018-10-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
|
Notes |
; We thank Matthias Van der Donck for fruitful discussions. This work was supported by the Research Foundation of Flanders (FWO-V1) through an aspirant research grant for R.V.P. and a postdoctoral grant for B.V.D. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:154728UA @ admin @ c:irua:154728 |
Serial |
5094 |
Permanent link to this record |
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|
Author |
Mulkers, J.; Hals, K.M.D.; Leliaert, J.; Milošević, M.V.; Van Waeyenberge, B.; Everschor-Sitte, K. |
Title |
Effect of boundary-induced chirality on magnetic textures in thin films |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
6 |
Pages |
064429 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In the quest for miniaturizing magnetic devices, the effects of boundaries and surfaces become increasingly important. Here we show how the recently predicted boundary-induced Dzyaloshinskii-Moriya interaction (DMI) affects the magnetization of ferromagnetic films with a C-infinity v symmetry and a perpendicular magnetic anisotropy. For an otherwise uniformly magnetized film, we find a surface twist when the magnetization in the bulk is canted by an in-plane external field. This twist at the surfaces caused by the boundary-induced DMI differs from the common canting caused by internal DMI observed at the edges of a chiral magnet. Furthermore, we find that the surface twist due to the boundary-induced DMI strongly affects the width of the domain wall at the surfaces. We also find that the skyrmion radius increases in the depth of the film, with the average size of the skyrmion increasing with boundary-induced DMI. This increase suggests that the boundary-induced DMI contributes to the stability of the skyrmion. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000443394600004 |
Publication Date |
2018-08-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
Notes |
; The authors thank Matthias Sitte and Andre Thiaville for fruitful discussions. This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N and the German Research Foundation (DFG) under the Project No. EV 196/2-1. J.L. is supported by the Ghent University Special Research Fund with a BOF postdoctoral fellowship. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:153706UA @ admin @ c:irua:153706 |
Serial |
5093 |
Permanent link to this record |
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Author |
Malkov, I., V; Krivetskii, V.V.; Potemkin, D., I; Zadesenets, A., V; Batuk, M.M.; Hadermann, J.; Marikutsa, A., V; Rumyantseva, M.N.; Gas'kov, A.M. |
Title |
Effect of Bimetallic Pd/Pt Clusters on the Sensing Properties of Nanocrystalline SnO2 in the Detection of CO |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Russian journal of inorganic chemistry |
Abbreviated Journal |
Russ J Inorg Chem+ |
Volume |
63 |
Issue |
8 |
Pages |
1007-1011 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Nanocrystalline tin dioxide modified by Pd and Pt clusters or by bimetallic PdPt nanoparticles was synthesized. Distribution of the modifers on the SnO2 surface was studied by high-resolution transmission electron microscopy and energy dispersive X-ray microanalysis with element distribution mapping. It was shown that the Pd/Pt ratio in bimetallic particles varies over a broad range and does not depend on the particle diameter. The effect of platinum metals on the reducibility of nanocrystalline SnO2 by hydrogen was determined. The sensing properties of the resulting materials towards 6.7 ppm CO in air were estimated in situ by electrical conductivity measurements. The sensor response of SnO2 modified with bimetallic PdPt particles was a superposition of the signals of samples with Pt and Pd clusters. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000442749500003 |
Publication Date |
2018-08-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition ![sorted by Edition field, descending order (down)](img/sort_desc.gif) |
|
ISSN |
0036-0236 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.787 |
Times cited |
3 |
Open Access |
Not_Open_Access |
Notes |
; This work was supported by the ERA.Net RUS Plus program (project 096 FONSENS, RFBR grant 16-53-76001). ; |
Approved |
Most recent IF: 0.787 |
Call Number |
UA @ lucian @ c:irua:153752 |
Serial |
5092 |
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Author |
Zhou, Y.; Che, F.; Liu, M.; Zou, C.; Liang, Z.; De Luna, P.; Yuan, H.; Li, J.; Wang, Z.; Xie, H.; Li, H.; Chen, P.; Bladt, E.; Quintero-Bermudez, R.; Sham, T.-K.; Bals, S.; Hofkens, J.; Sinton, D.; Chen, G.; Sargent, E.H. |
Title |
Dopant-induced electron localization drives CO2 reduction to C2 hydrocarbons |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Nature chemistry |
Abbreviated Journal |
Nat Chem |
Volume |
10 |
Issue |
10 |
Pages |
974-980 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The electrochemical reduction of CO2 to multi-carbon products has attracted much attention because it provides an avenue to the synthesis of value-added carbon-based fuels and feedstocks using renewable electricity. Unfortunately, the efficiency of CO2 conversion to C-2 products remains below that necessary for its implementation at scale. Modifying the local electronic structure of copper with positive valence sites has been predicted to boost conversion to C-2 products. Here, we use boron to tune the ratio of Cu delta+ to Cu-0 active sites and improve both stability and C-2-product generation. Simulations show that the ability to tune the average oxidation state of copper enables control over CO adsorption and dimerization, and makes it possible to implement a preference for the electrosynthesis of C-2 products. We report experimentally a C-2 Faradaic efficiency of 79 +/- 2% on boron-doped copper catalysts and further show that boron doping leads to catalysts that are stable for in excess of similar to 40 hours while electrochemically reducing CO2 to multi-carbon hydrocarbons. |
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Wos |
000442395200013 |
Publication Date |
2018-07-13 |
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ISSN |
1755-4330; 1755-4349 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
25.87 |
Times cited |
700 |
Open Access |
OpenAccess |
Notes |
; This work was supported financially by funding from TOTAL S.A., the Ontario Research Fund: Research Excellence Program, the Natural Sciences and Engineering Research Council of Canada, the CIFAR Bio-Inspired Solar Energy programme, a University of Toronto Connaught grant, the Ministry of Science, Natural Science Foundation of China (21471040, 21271055 and 21501035), the Innovation-Driven Plan in Central South University project (2017CX003), a project from State Key Laboratory of Powder Metallurgy in Central South University, the Thousand Youth Talents Plan of China and Hundred Youth Talents Program of Hunan and the China Scholarship Council programme. This work benefited from the soft X-ray microcharacterization beamline at CLS, sector 20BM at the APS and the Ontario Centre for the Characterisation of Advanced Materials at the University of Toronto. H.Y. acknowledges financial support from the Research Foundation-Flanders (FWO postdoctoral fellowship). C.Z. acknowledges support from the International Academic Exchange Fund for Joint PhD Students from Tianjin University. P.D.L. acknowledges financial support from the Natural Sciences and Engineering Research Council in the form of the Canada Graduate Scholarship-Doctoral award. S.B. and E.B. acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). The authors thank B. Zhang, N. Wang, C. T. Dinh, T. Zhuang, J. Li and Y. Zhao for fruitful discussions, as well as Y. Hu and Q. Xiao from CLS, and Z. Finfrock and M. Ward from APS for their help during the course of study. Computations were performed on the SOSCIP Consortium's Blue Gene/Q computing platform. SOSCIP is funded by the Federal Economic Development Agency of Southern Ontario, the Province of Ontario, IBM Canada, Ontario Centres of Excellence, Mitacs and 15 Ontario academic member institutions. ; ecas_sara |
Approved |
Most recent IF: 25.87 |
Call Number |
UA @ lucian @ c:irua:153693UA @ admin @ c:irua:153693 |
Serial |
5091 |
Permanent link to this record |