Records |
Author |
Clima, S.; Belmonte, A.; Degraeve, R.; Fantini, A.; Goux, L.; Govoreanu, B.; Jurczak, M.; Ota, K.; Redolfi, A.; Kar, G.S.; Pourtois, G. |
Title |
Kinetic and thermodynamic heterogeneity : an intrinsic source of variability in Cu-based RRAM memories |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
Volume |
16 |
Issue |
4 |
Pages |
1011-1016 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('The resistive random-access memory (RRAM) device concept is close to enabling the development of a new generation of non-volatile memories, provided that their reliability issues are properly understood. The design of a RRAM operating with extrinsic defects based on metallic inclusions, also called conductive bridge RAM, allows the use of a large spectrum of solid electrolytes. However, when scaled to device dimensions that meet the requirements of the latest technological nodes, the discrete nature of the atomic structure of the materials impacts the device operation. Using density functional theory simulations, we evaluated the migration kinetics of Cu conducting species in amorphous and solid electrolyte materials, and established that atomic disorder leads to a large variability in terms of defect stability and kinetic barriers. This variability has a significant impact on the filament resistance and its dynamics, as evidenced during the formation step of the resistive filament. Also, the atomic configuration of the formed filament can age/relax to another metastable atomic configuration, and lead to a modulation of the resistivity of the filament. All these observations are qualitatively explained on the basis of the computed statistical distributions of the defect stability and on the kinetic barriers encountered in RRAM materials.')); |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Place of publication unknown |
Editor |
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Language |
|
Wos |
000417598100004 |
Publication Date |
2017-08-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1569-8025 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.526 |
Times cited |
2 |
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 1.526 |
Call Number |
UA @ lucian @ c:irua:148569 |
Serial |
4883 |
Permanent link to this record |
|
|
|
Author |
Peymanirad, F.; Singh, S.K.; Ghorbanfekr-Kalashami, H.; Novoselov, K.S.; Peeters, F.M.; Neek-Amal, M. |
Title |
Thermal activated rotation of graphene flake on graphene |
Type |
A1 Journal article |
Year |
2017 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
4 |
Issue |
2 |
Pages |
025015 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The self rotation of a graphene flake over graphite is controlled by the size, initial misalignment and temperature. Using both ab initio calculations and molecular dynamics simulations, we investigate annealing effects on the self rotation of a graphene flake on a graphene substrate. The energy barriers for rotation and drift of a graphene flake over graphene is found to be smaller than 25 meV/atom which is comparable to thermal energy. We found that small flakes (of about similar to 4 nm) are more sensitive to temperature and initial misorientation angles than larger one (beyond 10 nm). The initial stacking configuration of the flake is found to be important for its dynamics and time evolution of misalignment. Large flakes, which are initially in the AA-or AB-stacking state with small misorientation angle, rotate and end up in the AB-stacking configuration. However small flakes can they stay in an incommensurate state specially when the initial misorientation angle is larger than 2 degrees. Our results are in agreement with recent experiments. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000424399600005 |
Publication Date |
2017-02-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
16 |
Open Access |
|
Notes |
; We would like to acknowledge Annalisa Fasolino and MM van Wijk for providing us with the implemented parameters of REBO-KC [5] in LAMMPS. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:149364 |
Serial |
4984 |
Permanent link to this record |
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Author |
Verreck, D.; Verhulst, A.S.; Van de Put, M.L.; Sorée, B.; Magnus, W.; Collaert, N.; Mocuta, A.; Groeseneken, G. |
Title |
Self-consistent 30-band simulation approach for (non-)uniformly strained confined heterostructure tunnel field-effect transistors |
Type |
P1 Proceeding |
Year |
2017 |
Publication |
Simulation of Semiconductor Processes and, Devices (SISPAD)AND DEVICES (SISPAD 2017) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
29-32 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
Heterostructures of III-V materials under a mechanical strain are being actively researched to enhance the performance of the tunnel field-effect transistor (TFET). In scaled III-V device structures, however, the interplay between the effects of strain and quantum confinement on the semiconductor band structure and hence the performance is highly non-trivial. We have therefore developed a computationally efficient quantum mechanical simulator Pharos, which enables self-consistent full-zone k.p-based simulations of III-V TFETs under a general non-uniform strain. We present the self-consistent procedure and demonstrate it on confined staggered bandgap GaAs0.5Sb0.5/In0.53Ga0.47As TFETs. We find a large performance degradation due to size-induced quantum confinement compared to non-confined devices. We show that some performance can be regained either by applying a uniform biaxial tensile strain or through the non-uniform strain profile at a lattice-mismatched heterostructure. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
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Publication Date |
|
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-4-86348-610-2 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:149949 |
Serial |
4978 |
Permanent link to this record |
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|
|
Author |
Loo, R.; Arimura, H.; Cott, D.; Witters, L.; Pourtois, G.; Schulze, A.; Douhard, B.; Vanherle, W.; Eneman, G.; Richard, O.; Favia, P.; Mitard, J.; Mocuta, D.; Langer, R.; Collaert, N. |
Title |
Epitaxial CVD growth of ultra-thin Si passivation layers on strained Ge fin structures |
Type |
P1 Proceeding |
Year |
2017 |
Publication |
Semiconductor Process Integration 10 |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
241-252 |
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Epitaxially grown ultra-thin Si layers are often used to passivate Ge surfaces in the high-k gate module of (strained) Ge FinFET devices. We use Si4H10 as Si precursor as it enables epitaxial Si growth at temperatures down to 330 degrees C. C-V characteristics of blanket capacitors made on Ge virtual substrates point to the presence of an optimal Si thickness. In case of compressively strained Ge fin structures, the Si growth results in non-uniform and high strain levels in the strained Ge fin. These strain levels have been calculated for different shapes of the Ge fin and in function of the grown Si thickness. The high strain is the driving force for potential (unwanted) Ge surface reflow during the Si deposition. The Ge surface reflow is strongly affected by the strength of the H-passivation during Si-capping and can be avoided by carefully selected process conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Electrochemical soc inc |
Place of Publication |
Pennington |
Editor |
|
Language |
|
Wos |
000426269800024 |
Publication Date |
2017-10-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
80 |
Series Issue |
4 |
Edition |
|
ISSN |
978-1-60768-821-1; 978-1-62332-473-5 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:149965 |
Serial |
4966 |
Permanent link to this record |
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|
|
Author |
Pourtois, G.; Dabral, A.; Sankaran, K.; Magnus, W.; Yu, H.; de de Meux, A.J.; Lu, A.K.A.; Clima, S.; Stokbro, K.; Schaekers, M.; Houssa, M.; Collaert, N.; Horiguchi, N. |
Title |
Probing the intrinsic limitations of the contact resistance of metal/semiconductor interfaces through atomistic simulations |
Type |
P1 Proceeding |
Year |
2017 |
Publication |
Semiconductors, Dielectrics, And Metals For Nanoelectronics 15: In Memory Of Samares Kar |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
303-311 |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this contribution, we report a fundamental study of the factors that set the contact resistivity between metals and highly doped semiconductors. We investigate the case of n-type doped Si contacted with amorphous TiSi combining first-principles calculations with Non-Equilibrium Green functions transport simulations. The intrinsic contact resistivity is found to saturate at similar to 2x10(-10) Omega.cm(2) with the doping concentration and sets an intrinsic limit to the ultimate contact resistance achievable for n-doped Si vertical bar amorphous-TiSi. This limit arises from the intrinsic properties of the semiconductor and of the metal such as their electron effective masses and Fermi energies. We illustrate that, in this regime, contacting metals with a heavy electron effective mass helps reducing the interface intrinsic contact resistivity. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Electrochemical soc inc |
Place of Publication |
Pennington |
Editor |
|
Language |
|
Wos |
000426271800028 |
Publication Date |
2017-10-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
80 |
Series Issue |
1 |
Edition |
|
ISSN |
978-1-62332-470-4; 978-1-60768-818-1 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
Not_Open_Access |
Notes |
; ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:149966 |
Serial |
4976 |
Permanent link to this record |
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|
|
Author |
Perez, A.J.; Jacquet, Q.; Batuk, D.; Iadecola, A.; Saubanere, M.; Rousse, G.; Larcher, D.; Vezin, H.; Doublet, M.-L.; Tarascon, J.-M. |
Title |
Approaching the limits of cationic and anionic electrochemical activity with the Li-rich layered rocksalt Li3IrO4 |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature energy |
Abbreviated Journal |
Nat Energy |
Volume |
2 |
Issue |
12 |
Pages |
954-962 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The Li-rich rocksalt oxides Li2MO3 (M = 3d/4d/5d transition metal) are promising positive-electrode materials for Li-ion batteries, displaying capacities exceeding 300 mAh g(-1) thanks to the participation of the oxygen non-bonding O(2p) orbitals in the redox process. Understanding the oxygen redox limitations and the role of the O/M ratio is therefore crucial for the rational design of materials with improved electrochemical performances. Here we push oxygen redox to its limits with the discovery of a Li3IrO4 compound (O/M = 4) that can reversibly take up and release 3.5 electrons per Ir and possesses the highest capacity ever reported for any positive insertion electrode. By quantitatively monitoring the oxidation process, we demonstrate the material's instability against O-2 release on removal of all Li. Our results show that the O/M parameter delineates the boundary between the material's maximum capacity and its stability, hence providing valuable insights for further development of high-capacity materials. |
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 |
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Language |
|
Wos |
000430218300001 |
Publication Date |
2017-12-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2058-7546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
55 |
Open Access |
Not_Open_Access |
Notes |
; We thank P. Pearce for providing the beta-Li<INF>2</INF>IrO<INF>3</INF> and L. Lemarquis for helping in the DEMS experiment. We are particularly grateful to S. Belin, V. Briois and L. Stievano for helpful discussions on XAS analysis and synchrotron SOLEIL (France) for providing beamtime at the ROCK beamline (financed by the French National Research Agency (ANR) as part of the 'Investissements d'Avenir' programme, reference: ANR-10-EQPX-45). A.J.P and A. I. acknowledge the GdR C(RS) 2 for the workshop organized on a chemometric approach for XAS data analysis. V. Nassif is acknowledged for her help during neutron diffraction experiments performed at Institut Laue Langevin on D1B. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is gratefully acknowledged. This work has been performed with the support of the European Research Council (ERC) (FP/2014)/ERC Grant- Project 670116 ARPEMA. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:150926 |
Serial |
4962 |
Permanent link to this record |
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|
Author |
Bueken, B.; Van Velthoven, N.; Willhammar, T.; Stassin, T.; Stassen, I.; Keen, D.A.; Baron, G.V.; Denayer, J.F.M.; Ameloot, R.; Bals, S.; De Vos, D.; Bennett, T.D. |
Title |
Gel-based morphological design of zirconium metal-organic frameworks |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
Volume |
8 |
Issue |
8 |
Pages |
3939-3948 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The ability of metal-organic frameworks (MOFs) to gelate under specific synthetic conditions opens up new opportunities in the preparation and shaping of hierarchically porous MOF monoliths, which could be directly implemented for catalytic and adsorptive applications. In this work, we present the first examples of xero-or aerogel monoliths consisting solely of nanoparticles of several prototypical Zr4+-based MOFs: UiO-66-X (X – H, NH2, NO2, (OH)(2)), UiO-67, MOF-801, MOF-808 and NU-1000. High reactant and water concentrations during synthesis were observed to induce the formation of gels, which were converted to monolithic materials by drying in air or supercritical CO2. Electron microscopy, combined with N-2 physisorption experiments, was used to show that irregular nanoparticle packing leads to pure MOF monoliths with hierarchical pore systems, featuring both intraparticle micropores and interparticle mesopores. Finally, UiO-66 gels were shaped into monolithic spheres of 600 mm diameter using an oil-drop method, creating promising candidates for packed-bed catalytic or adsorptive applications, where hierarchical pore systems can greatly mitigate mass transfer limitations. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Royal Society of Chemistry |
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000400553000077 |
Publication Date |
2017-03-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-6520 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.668 |
Times cited |
168 |
Open Access |
OpenAccess |
Notes |
; B. B., T. S. and I. S. acknowledge the FWO Flanders (doctoral and post-doctoral grants). T. W. acknowledges a post-doctoral grant from the Swedish Research Council. T. D. B. acknowledges the Royal Society (University Research Fellowship) and Trinity Hall (University of Cambridge) for funding. S. B. and D. D. V. are grateful for funding by Belspo (IAP 7/05 P6/27) and by the FWO Flanders. D. D. V. further acknowledges funding from the European Research Council (project H-CCAT). S. B. acknowledges financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). The authors acknowledge Arnau Carne and Shuhei Furukawa for assistance with supercritical CO<INF>2</INF> extraction, and Charles Ghesquiere for assistance in synthesis. ; Ecas_Sara |
Approved |
Most recent IF: 8.668 |
Call Number |
UA @ lucian @ c:irua:152643UA @ admin @ c:irua:152643 |
Serial |
5143 |
Permanent link to this record |
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|
Author |
Van Tendeloo, L.; Wangermez, W.; Vandekerkhove, A.; Willhammar, T.; Bals, S.; Maes, A.; Martens, J.A.; Kirschhock, C.E.A.; Breynaert, E. |
Title |
Postsynthetic high-alumina zeolite crystal engineering in organic free hyper-alkaline media |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
29 |
Issue |
29 |
Pages |
629-638 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Postsynthetic modification of high -alumina zeolites in hyper alkaline media can be tailored toward alteration of framework topology, crystal size and morphology, or desired Si/A1 ratio. FAU, EMT, MAZ, KFI, HEU, and LTA starting materials were treated with 1.2 M MOH (M = Na, K, RE, or Cs), leading to systematic ordered porosity or fully transformed frameworks with new topology and adjustable Si/Al ratio. In addition to the versatility of this tool for zeolite crystal engineering, these alterations improve understanding of the crystal chemistry. Such knowledge can guide further development in zeolite crystal engineering. Postsynthetic alteration also provides insight on the long-term stability of aluminosilicate zeolites that are used as a sorption sink in concrete -based waste disposal facilities in harsh alkaline conditions. |
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 |
000392891700021 |
Publication Date |
2016-12-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
16 |
Open Access |
OpenAccess |
Notes |
; This work was supported by long-term structural funding by the Flemish Government (Methusalem grant of Prof. J. Martens) and by ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and Fissile Materials, as part of the program on surface disposal of Belgian Category A waste. The Belgian government is acknowledged for financing the interuniversity poles of attraction (IAP-PAI). S.B. acknowledges financial support from European Research Council (ERC Advanced Grant No. 24691-COUNTATOMS, ERC Starting Grant No. 335078-COLOURATOMS). ; Ecas_Sara |
Approved |
Most recent IF: 9.466 |
Call Number |
UA @ lucian @ c:irua:152674UA @ admin @ c:irua:152674 |
Serial |
5145 |
Permanent link to this record |
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Author |
Shetty, S.; Sinha, S.K.; Ahmad, R.; Singh, A.K.; Van Tendeloo, G.; Ravishankar, N. |
Title |
Existence of Ti2+States on the Surface of Heavily Reduced SrTiO3Nanocubes |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
|
Issue |
|
Pages |
acs.chemmater.7b04113 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Using advanced electron microscopy, we demonstrate the presence of Ti2+ on the 001 surfaces of heavily reduced strontium titanate nanocubes. While high-angle annular dark field images show a clear difference between the surfaces of the unreduced and reduced samples, electron energy loss spectroscopy detects the presence of Ti2+ on the surface of the reduced cubes. Conventional reduction only leads to the formation of Ti3+ and involves the use of high temperatures. In our case, reduction is achieved at relatively lower temperatures in the solid state using sodium borohydride as the reducing agent. Our findings provide insights into the optical properties of the samples and provide a convenient method to produce highly reduced surfaces that could demonstrate a range of exotic physical phenomena |
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 |
|
Language |
|
Wos |
000418206600005 |
Publication Date |
2017-11-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
8 |
Open Access |
OpenAccess |
Notes |
We thank Advanced Facility for Microscopy and Microanalysis (AFMM), IISc, Bangalore for providing the TEM facility. We also thank MNCF, CeNSE, IISc for providing the XPS and FT-IR facilities. We acknowledge the help from Prof. Anshu Pandey for providing the PL facility and Mr. Ashutosh Gupta for the help with measurements. SS and NR thank DST for providing the financial support. RA and AKS acknowledge Super Computing Education and Research Center (SERC) and Materials Research Center (MRC), at IISc for providing required computational facilities. RA acknowledges the financial support from INSPIRE fellowship, AORC.Science and Engineering Research Board; Federaal Wetenschapsbeleid; Department of Science and Technology, Ministry of Science and Technology; |
Approved |
Most recent IF: 9.466 |
Call Number |
UA @ lucian @c:irua:147191 |
Serial |
4767 |
Permanent link to this record |