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Author | Macke, S.; Radi, A.; Hamann-Borrero, J.E.; Verna, A.; Bluschke, M.; Brück, S.; Goering, E.; Sutarto, R.; He, F.; Cristiani, G.; Wu, M.; Benckiser, E.; Habermeier, H.-U.; Logvenov, G.; Gauquelin, N.; Botton, G.A; Kajdos, A.P.; Stemmer, S.; Sawatzky,G.A.; Haverkort, M.W.; Keimer, B.; Hinkov, V. | ||||
Title | Element Specific Monolayer Depth Profiling | Type | A1 Journal Article | ||
Year | 2014 | Publication | Advanced Materials | Abbreviated Journal | Adv Mater |
Volume | 26 | Issue | 38 | Pages | 6554-6559 |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) | ||||
Abstract | The electronic phase behavior and functionality of interfaces and surfaces in complex materials are strongly correlated to chemical composition profiles, stoichiometry and intermixing. Here a novel analysis scheme for resonant X-ray reflectivity maps is introduced to determine such profiles, which is element specific and non-destructive, and which exhibits atomic-layer resolution and a probing depth of hundreds of nanometers. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000343763200004 | Publication Date | 2014-08-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1521-4095 | ISBN | Additional Links | ||
Impact Factor | 19.791 | Times cited | 34 | Open Access | |
Notes | Approved | Most recent IF: 19.791; 2014 IF: NA | |||
Call Number | EMAT @ emat @ | Serial | 4541 | ||
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Author | Egoavil, R.; Gauquelin, N.; Martinez, G.T.; Van Aert, S.; Van Tendeloo, G.; Verbeeck, J. | ||||
Title | Atomic resolution mapping of phonon excitations in STEM-EELS experiments | Type | A1 Journal article | ||
Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 147 | Issue | Pages | 1-7 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Atomically resolved electron energy-loss spectroscopy experiments are commonplace in modern aberration-corrected transmission electron microscopes. Energy resolution has also been increasing steadily with the continuous improvement of electron monochromators. Electronic excitations however are known to be delocalized due to the long range interaction of the charged accelerated electrons with the electrons in a sample. This has made several scientists question the value of combined high spatial and energy resolution for mapping interband transitions and possibly phonon excitation in crystals. In this paper we demonstrate experimentally that atomic resolution information is indeed available at very low energy losses around 100 meV expressed as a modulation of the broadening of the zero loss peak. Careful data analysis allows us to get a glimpse of what are likely phonon excitations with both an energy loss and gain part. These experiments confirm recent theoretical predictions on the strong localization of phonon excitations as opposed to electronic excitations and show that a combination of atomic resolution and recent developments in increased energy resolution will offer great benefit for mapping phonon modes in real space. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000343157400001 | Publication Date | 2014-05-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 22 | Open Access | |
Notes | 246102 IFOX; 278510 VORTEX; 246791 COUNTATOMS; Hercules; 312483 ESTEEM2; esteem2jra3 ECASJO; | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
Call Number | UA @ lucian @ c:irua:118332UA @ admin @ c:irua:118332 | Serial | 177 | ||
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Author | Morozov, V.A.; Lazoryak, B.I.; Shmurak, S.Z.; Kiselev, A.P.; Lebedev, O.I.; Gauquelin, N.; Verbeeck, J.; Hadermann, J.; Van Tendeloo, G. | ||||
Title | Influence of the structure on the properties of NaxEuy(MoO4)z red phosphors | Type | A1 Journal article | ||
Year | 2014 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 26 | Issue | 10 | Pages | 3238-3248 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Scheelite related compounds (A',A '')(n)[(B',B '')O-4](m) with B', B '' = W and/or Mo are promising new materials for red phosphors in pc-WLEDs (phosphor-converted white-light-emitting-diode) and solid-state lasers. Cation substitution in CaMoO4 of Ca2+ by the combination of Na+ and Eu3+, with the creation of A cation vacancies, has been investigated as a factor for controlling the scheelite-type structure and the luminescent properties. Na5Eu(MoO4)(4) and NaxEu(2-x)/33+square(2-x)/3MoO4 (0.138 <= x <= 0.5) phases with a scheelite-type structure were synthesized by the solid state method; their structural characteristics were investigated using transmission electron microscopy. Contrary to powder synchrotron X-ray diffraction before, the study by electron diffraction and high resolution transmission electron microscopy in this paper revealed that Na0.286Eu0.571MoO4 has a (3 + 2)D incommensurately modulated structure and that (3 + 2)D incommensurately modulated domains are present in Na0.200Eu0.600MoO4. It also confirmed the (3 + 1)D incommensurately modulated character of Na(0.138)Eu(0.621)Mo04. The luminescent properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of these phosphors show the strongest absorption at about 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The emission spectra indicate an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+, with local minima in the intensity at Na0.286Eu0.571MoO4 and Na0.200Eu0.600MoO4 for similar to 613 nm and similar to 616 nm bands. The phosphor Na5Eu(MoO4)(4) shows the brightest red light emission among the phosphors in the Na2MoO4-Eu2/3MoO4 system and the maximum luminescence intensity of Na5Eu(MoO4)(4) (lambda(ex) = 395 nm) in the D-5(0) -> F-7(2) transition region is close to that of the commercially used red phosphor YVO4:Eu3+ (lambda(ex) = 326 nm). Electron energy loss spectroscopy measurements revealed the influence of the structure and Na/Eu cation distribution on the number and positions of bands in the UV-optical-infrared regions of the EELS spectrum. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000336637000028 | Publication Date | 2014-05-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756;1520-5002; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 53 | Open Access | |
Notes | Fwo G039211n; Fwo G004413n; 278510 Vortex ECASJO_; | Approved | Most recent IF: 9.466; 2014 IF: 8.354 | ||
Call Number | UA @ lucian @ c:irua:117765UA @ admin @ c:irua:117765 | Serial | 1652 | ||
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Author | Stambula, S.; Gauquelin, N.; Bugnet, M.; Gorantla, S.; Turner, S.; Sun, S.; Liu, J.; Zhang, G.; Sun, X.; Botton, G.A. | ||||
Title | Chemical structure of nitrogen-doped graphene with single platinum atoms and atomic clusters as a platform for the PEMFC electrode | Type | A1 Journal article | ||
Year | 2014 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 118 | Issue | 8 | Pages | 3890-3900 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A platform for producing stabilized Pt atoms and clusters through the combination of an N-doped graphene support and atomic layer deposition (ALD) for the Pt catalysts was investigated using transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). It was determined, using imaging and spectroscopy techniques, that a wide range of N-dopant types entered the graphene lattice through covalent bonds without largely damaging its structure. Additionally and most notably, Pt atoms and atomic clusters formed in the absence of nanoparticles. This work provides a new strategy for experimentally producing stable atomic and subnanometer cluster catalysts, which can greatly assist the proton exchange membrane fuel cell (PEMFC) development by producing the ultimate surface area to volume ratio catalyst. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000332188100004 | Publication Date | 2014-02-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 57 | Open Access | |
Notes | Fwo | Approved | Most recent IF: 4.536; 2014 IF: 4.772 | ||
Call Number | UA @ lucian @ c:irua:115571 | Serial | 352 | ||
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Author | Shuhui Sun, Gaixia Zhang, Nicolas Gauquelin, Ning Chen, Jigang Zhou, Songlan Yang, Weifeng Chen, Xiangbo Meng, Dongsheng Geng, Mohammad N. Banis, Ruying Li, Siyu Ye, Shanna Knights, Gianluigi A. Botton, Tsun-Kong Sham & Xueliang Sun | ||||
Title | Single-atom Catalysis Using Pt/Graphene Achieved through Atomic Layer Deposition | Type | A1 Journal Article | ||
Year | 2013 | Publication | Scientific Reports | Abbreviated Journal | |
Volume | 3 | Issue | Pages | 1775 | |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | Platinum-nanoparticle-based catalysts are widely used in many important chemical processes and automobile industries. Downsizing catalyst nanoparticles to single atoms is highly desirable to maximize their use efficiency, however, very challenging. Here we report a practical synthesis for isolated single Pt atoms anchored to graphene nanosheet using the atomic layer deposition (ALD) technique. ALD offers the capability of precise control of catalyst size span from single atom, subnanometer cluster to nanoparticle. The single-atom catalysts exhibit significantly improved catalytic activity (up to 10 times) over that of the state-of-the-art commercial Pt/C catalyst. X-ray absorption fine structure (XAFS) analyses reveal that the low-coordination and partially unoccupied densities of states of 5d orbital of Pt atoms are responsible for the excellent performance. This work is anticipated to form the basis for the exploration of a next generation of highly efficient single-atom catalysts for various applications. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000318334300004 | Publication Date | 2013-05-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Additional Links | |||
Impact Factor | Times cited | 345 | Open Access | ||
Notes | Approved | Most recent IF: NA | |||
Call Number | EMAT @ emat @ | Serial | 4543 | ||
Permanent link to this record |