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Records |
Links |
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Author |
Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B. |
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Title |
The origin of p-type conductivity in ZnM2O4 (M = Co, Rh, Ir) spinels |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
16 |
Issue |
6 |
Pages |
2588-2596 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000329926700040 |
Publication Date |
2013-12-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
47 |
Open Access |
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Notes |
Fwo; Goa; Hercules |
Approved |
Most recent IF: 4.123; 2014 IF: 4.493 |
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Call Number |
UA @ lucian @ c:irua:114829 |
Serial |
2525 |
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Permanent link to this record |
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Author |
Sliem, M.A.; Turner, S.; Heeskens, D.; Kalidindi, S.B.; Van Tendeloo, G.; Muhler, M.; Fischer, R.A. |
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Title |
Preparation, microstructure characterization and catalytic performance of Cu/ZnO and ZnO/Cu composite nanoparticles for liquid phase methanol synthesis |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
14 |
Issue |
22 |
Pages |
8170-8178 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Stearate@Cu/ZnO nanocomposite particles with molar ratios of ZnO ∶ Cu = 2 and 5 are synthesized by reduction of the metalorganic Cu precursor [Cu{(OCH(CH3)CH2N(CH3)2)}2] in the presence of stearate@ZnO nanoparticles. In the case of ZnO ∶ Cu = 5, high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) combined with electron-energy-loss-spectroscopy (EELS) as well as attenuated total reflection Fourier transform infrared (ATR-IR) spectroscopy are used to localize the small amount of Cu deposited on the surface of 35 nm sized stearate@ZnO particles. For ZnO ∶ Cu = 2, the microstructure of the nanocomposites after catalytic activity testing is characterized by HAADF-STEM techniques. This reveals the construction of large Cu nanoparticles (2050 nm) decorated by small ZnO nanoparticles (35 nm). The catalytic activity of both composites for the synthesis of methanol from syn gas is evaluated. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000304102200033 |
Publication Date |
2012-04-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
16 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 4.123; 2012 IF: 3.829 |
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Call Number |
UA @ lucian @ c:irua:98377 |
Serial |
2702 |
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Permanent link to this record |
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Author |
Aerts, A.; Follens, L.R.A.; Biermans, E.; Bals, S.; Van Tendeloo, G.; Loppinet, B.; Kirschhock, C.E.A.; Martens, J.A. |
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Title |
Modelling of synchrotron SAXS patterns of silicalite-1 zeolite during crystallization |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
13 |
Issue |
10 |
Pages |
4318-4325 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Synchrotron small angle X-ray scattering (SAXS) was used to characterize silicalite-1 zeolite crystallization from TEOS/TPAOH/water clear sol. SAXS patterns were recorded over a broad range of length scales, enabling the simultaneous monitoring of nanoparticles and crystals occurring at various stages of the synthesis. A simple two-population model accurately described the patterns. Nanoparticles were modeled by polydisperse coreshell spheres and crystals by monodisperse oblate ellipsoids. These models were consistent with TEM images. The SAXS results, in conjunction with in situ light scattering, showed that nucleation of crystals occurred in a short period of time. Crystals were uniform in size and shape and became increasingly anisotropic during growth. In the presence of nanoparticles, crystal growth was fast. During crystal growth, the number of nanoparticles decreased gradually but their size was constant. These observations suggested that the nanoparticles were growth units in an aggregative crystal growth mechanism. Crystals grown in the presence of nanoparticles developed a faceted habit and intergrowths. In the final stages of growth, nanoparticles were depleted. Concurrently, the crystal growth rate decreased significantly. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000287584700017 |
Publication Date |
2011-01-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
22 |
Open Access |
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Notes |
Fwo; Iap; Esteem 026019 |
Approved |
Most recent IF: 4.123; 2011 IF: 3.573 |
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Call Number |
UA @ lucian @ c:irua:87602 |
Serial |
2155 |
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Permanent link to this record |
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Author |
Zeng, Y.I.; Menghini, M.; Li, D.Y.; Lin, S.S.; Ye, Z.Z.; Hadermann, J.; Moorkens, T.; Seo, J.W.; Locquet, J.-P.; van Haesendonck, C. |
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Title |
Unexpected optical response of single ZnO nanowires probed using controllable electrical contacts |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
13 |
Issue |
15 |
Pages |
6931-6935 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Relying on combined electron-beam lithography and lift-off methods Au/Ti bilayer electrical contacts were attached to individual ZnO nanowires (NWs) that were grown by a vapor phase deposition method. Reliable Schottky-type as well as ohmic contacts were obtained depending on whether or not an ion milling process was used. The response of the ZnO NWs to ultraviolet light was found to be sensitive to the type of contacts. The intrinsic electronic properties of the ZnO NWs were studied in a field-effect transistor configuration. The transfer characteristics, including gate threshold voltage, hysteresis and operational mode, were demonstrated to unexpectedly respond to visible light. The origin of this effect could be accounted for by the presence of point defects in the ZnO NWs. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000288951000019 |
Publication Date |
2011-03-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.123; 2011 IF: 3.573 |
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Call Number |
UA @ lucian @ c:irua:89378 |
Serial |
3807 |
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Permanent link to this record |
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Author |
Hermans, I.; Breynaert, E.; Poelman, H.; de Gryse, R.; Liang, D.; Van Tendeloo, G.; Maes, A.; Peeters, J.; Jacobs, P. |
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Title |
Silica-supported chromium oxide: colloids as building blocks |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
9 |
Issue |
39 |
Pages |
5382-5386 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000249925500022 |
Publication Date |
2007-10-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.123; 2007 IF: 3.343 |
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Call Number |
UA @ lucian @ c:irua:66752 |
Serial |
3000 |
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Permanent link to this record |
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Author |
Huang, W.; Zhang, X.-B.; Tu, J.; Kong, F.; Ning, Y.; Xu, J.; Van Tendeloo, G. |
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Title |
Synthesis and characterization of graphite nanofibers deposited on nickel foams |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
4 |
Issue |
21 |
Pages |
5325-5329 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nickel foams were used as catalysts to dissociate acetylene and deposit carbon atoms. Graphite nanofibers with distinct structures were developed at 550degreesC with nickel foams pretreated with hydrogen. HREM observations showed that the graphite layers of the nanofibers were aligned at a certain angle to the fiber axis. It is suggested that hydrogen treatment and metal catalysts have a tremendous impact on the yields and microstructures of the graphite nanofibers. The growth mechanism of these fish-bone graphite nanofibers is also discussed. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000178635300016 |
Publication Date |
2002-10-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.123; 2002 IF: 1.838 |
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Call Number |
UA @ lucian @ c:irua:94938 |
Serial |
3411 |
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Permanent link to this record |
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Author |
Piedigrosso, P.; Konya, Z.; Colomer, J.-F.; Fonseca, A.; Van Tendeloo, G.; Nagy, J.B. |
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Title |
Production of differently shaped multi-wall carbon nanotubes using various cobalt supported catalysts |
Type |
A1 Journal article |
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Year |
2000 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
2 |
Issue |
1 |
Pages |
163-170 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Catalytic synthesis and transmission electron microscopy (TEM) of multi-wall carbon nanotubes are presented. Silica, zeolite and alumina supported cobalt catalysts were prepared by different methods (impregnation and ion-adsorption precipitation) and were used to produce nanotubes. The synthesis was carried out in a fixed bed flow reactor and the process was optimized in order to produce carbon nanotubes on a gram scale. The influence of various parameters such as the method of catalyst preparation, the nature of the support, cobalt concentration and reaction conditions on the formation of nanotubes was investigated. The carbon deposits were measured and the quality of nanotubes was determined by low and high resolution TEM. Multi-wall straight and coiled nanotubes were found to be fairly regular with an average inner (outer) diameter of 4-7 nm (8-23 nm) and with lengths up to 0.1 mm. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000084333800025 |
Publication Date |
2002-07-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
53 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.123; 2000 IF: 1.653 |
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Call Number |
UA @ lucian @ c:irua:102889 |
Serial |
2723 |
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Permanent link to this record |
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Author |
Ahenach, J.; Cool, P.; Vansant, E.F.; Lebedev, O.; van Landuyt, J. |
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Title |
Influence of water on the pillaring of montmorillonite with aminopropyltriethoxysilane |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
1 |
Issue |
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Pages |
3703-3708 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000081765300046 |
Publication Date |
2002-07-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.123; 1999 IF: NA |
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Call Number |
UA @ lucian @ c:irua:28250 |
Serial |
1660 |
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Permanent link to this record |
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Author |
Filez, M.; Redekop, E.A.; Galvita, V.V.; Poelman, H.; Meledina, M.; Turner, S.; Van Tendeloo, G.; Bell, A.T.; Marin, G.B. |
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Title |
The role of hydrogen during Pt-Ga nanocatalyst formation |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
18 |
Issue |
18 |
Pages |
3234-3243 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Hydrogen plays an essential role during the in situ assembly of tailored catalytic materials, and serves as key ingredient in multifarious chemical reactions promoted by these catalysts. Despite intensive debate for several decades, the existence and nature of hydrogen-involved mechanisms – such as hydrogen-spillover, surface migration – have not been unambiguously proven and elucidated up to date. Here, Pt-Ga alloy formation is used as a probe reaction to study the behavior and atomic transport of H and Ga, starting from Pt nanoparticles on hydrotalcite-derived Mg(Ga)(Al)Ox supports. In situ XANES spectroscopy, time-resolved TAP kinetic experiments, HAADF-STEM imaging and EDX mapping are combined to probe Pt, Ga and H in a series of H2 reduction experiments up to 650 degrees C. Mg(Ga)(Al)Ox by itself dissociates hydrogen, but these dissociated hydrogen species do not induce significant reduction of Ga3+ cations in the support. Only in the presence of Pt, partial reduction of Ga3+ into Gadelta+ is observed, suggesting that different reaction mechanisms dominate for Pt- and Mg(Ga)(Al)Ox-dissociated hydrogen species. This partial reduction of Ga3+ is made possible by Pt-dissociated H species which spillover onto non-reducible Mg(Al)Ox or partially reducible Mg(Ga)(Al)Ox and undergo long-range transport over the support surface. Moderately mobile Gadelta+Ox migrates towards Pt clusters, where Gadelta+ is only fully reduced to Ga0 on condition of immediate stabilization inside Pt-Ga alloyed nanoparticles. |
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Address |
Laboratory for Chemical Technology (LCT), Ghent University, Technologiepark 914, B-9052 Ghent, Belgium. hilde.poelman@ugent.be |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000369506000106 |
Publication Date |
2016-01-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
10 |
Open Access |
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Notes |
This work was supported by the Fund for Scientific Research Flanders (FWO: G.0209.11), the ‘Long Term Structural Methusalem Funding by the Flemish Government’, the IAP 7/05 Interuniversity Attraction Poles Programme – Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of beam time at the DUBBLE beam line of the ESRF and travel costs and a postdoctoral fellowship for S.T. The authors acknowledge the assistance from D. Banerjee (XAS campaign 26-01-979) at DUBBLE. E. A. Redekop acknowledges the Marie Curie International Incoming Fellowship granted by the European Commission (Grant Agreement No. 301703). The authors also express their gratitude to V. Bliznuk for acquisition of the TEM images. |
Approved |
Most recent IF: 4.123 |
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Call Number |
c:irua:132315 |
Serial |
4000 |
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Permanent link to this record |
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Author |
Bercx, M.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. |
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Title |
First-principles analysis of the spectroscopic limited maximum efficiency of photovoltaic absorber layers for CuAu-like chalcogenides and silicon |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
18 |
Issue |
18 |
Pages |
20542-20549 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Chalcopyrite semiconductors are of considerable interest for application as absorber layers in thin-film photovoltaic cells. When growing films of these compounds, however, they are often found to contain CuAu-like domains, a metastable phase of chalcopyrite. It has been reported that for CuInS2, the presence of the CuAu-like phase improves the short circuit current of the chalcopyrite-based photovoltaic cell. We investigate the thermodynamic stability of both phases for a selected list of I-III-VI2 materials using a first-principles density functional theory approach. For the CuIn-VI2 compounds, the difference in formation energy between the chalcopyrite and CuAu-like phase is found to be close to 2 meV per atom, indicating a high likelihood of the presence of CuAu-like domains. Next, we calculate the spectroscopic limited maximum efficiency (SLME) of the CuAu-like phase and compare the results with those of the corresponding chalcopyrite phase. We identify several candidates with a high efficiency, such as CuAu-like CuInS2, for which we obtain an SLME of 29% at a thickness of 500 nm. We observe that the SLME can have values above the Shockley-Queisser (SQ) limit, and show that this can occur because the SQ limit assumes the absorptivity to be a step function, thus overestimating the radiative recombination in the detailed balance approach. This means that it is possible to find higher theoretical efficiencies within this framework simply by calculating the J-V characteristic with an absorption spectrum. Finally, we expand our SLME analysis to indirect band gap absorbers by studying silicon, and find that the SLME quickly overestimates the reverse saturation current of indirect band gap materials, drastically lowering their calculated efficiency. |
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Address |
EMAT & CMT groups, Department of Physics, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171, 2020 Antwerp, Belgium. marnik.bercx@uantwerpen.be |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000381428600058 |
Publication Date |
2016-07-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
34 |
Open Access |
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Notes |
We acknowledge financial support of FWO-Vlaanderen through projects G.0150.13N and G.0216.14N and ERA-NET RUS Plus/FWO, Grant G0D6515N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO FWOVlaanderen. |
Approved |
Most recent IF: 4.123 |
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Call Number |
c:irua:135091 |
Serial |
4112 |
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Permanent link to this record |
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Author |
Calizzi, M.; Venturi, F.; Ponthieu, M.; Cuevas, F.; Morandi, V.; Perkisas, T.; Bals, S.; Pasquini, L. |
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Title |
Gas-phase synthesis of Mg-Ti nanoparticles for solid-state hydrogen storage |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
18 |
Issue |
18 |
Pages |
141-148 |
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Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
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Abstract |
Mg-Ti nanostructured samples with different Ti contents were prepared via compaction of nanoparticles grown by inert gas condensation with independent Mg and Ti vapour sources. The growth set-up offered the option to perform in situ hydrogen absorption before compaction. Structural and morphological characterisation was carried out by X-ray diffraction, energy dispersive spectroscopy and electron microscopy. The formation of an extended metastable solid solution of Ti in hcp Mg was detected up to 15 at% Ti in the as-grown nanoparticles, while after in situ hydrogen absorption, phase separation between MgH2 and TiH2 was observed. At a Ti content of 22 at%, a metastable Mg-Ti-H fcc phase was observed after in situ hydrogen absorption. The co-evaporation of Mg and Ti inhibited nanoparticle coalescence and crystallite growth in comparison with the evaporation of Mg only. In situ hydrogen absorption was beneficial to subsequent hydrogen behaviour, studied by high pressure differential scanning calorimetry and isothermal kinetics. A transformed fraction of 90% was reached within 100 s at 300 degrees C during both hydrogen absorption and desorption. The enthalpy of hydride formation was not observed to differ from bulk MgH2. |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000368755500014 |
Publication Date |
2015-11-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
31 |
Open Access |
Not_Open_Access |
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Notes |
; Part of this work was supported by the COST Action MP1103 “Nanostructured materials for solid-state hydrogen storage”. ; |
Approved |
Most recent IF: 4.123 |
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Call Number |
UA @ lucian @ c:irua:131589 |
Serial |
4184 |
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Permanent link to this record |
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Author |
Matsubara, M.; Saniz, R.; Partoens, B.; Lamoen, D. |
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Title |
Doping anatase TiO2with group V-b and VI-b transition metal atoms: a hybrid functional first-principles study |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
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Volume |
19 |
Issue |
19 |
Pages |
1945-1952 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We investigate the role of transition metal atoms of group V-b (V, Nb, Ta) and VI-b (Cr, Mo, W) as n- or p-type dopants in anatase TiO$2$ using thermodynamic
principles and density functional theory with the Heyd-Scuseria-Ernzerhof HSE06 hybrid functional. The HSE06 functional provides a realistic value for the band gap, which ensures a correct classification of dopants as shallow or deep donors or acceptors. Defect formation energies and thermodynamic transition levels are calculated taking into account the constraints imposed by the stability of TiO$2$ and the solubility limit of the impurities.
Nb, Ta, W and Mo are identified as shallow donors. Although W provides two electrons, Nb and Ta show a considerable lower formation energy, in particular under O-poor conditions. Mo donates in principle one electron, but under specific conditions can turn into a double donor. V impurities are deep donors and Cr
shows up as an amphoteric defect, thereby acting as an electron trapping center in n-type TiO$_2$ especially under O-rich conditions. A comparison with the available experimental data yields excellent agreement. |
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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 |
000394426400027 |
Publication Date |
2016-12-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
19 |
Open Access |
OpenAccess |
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Notes |
We gratefully acknowledge financial support from the IWTVlaanderenthrough projects G.0191.08 and G.0150.13, and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, which is funded by the Hercules foundation. M. M. acknowledges financial support from the GOA project ‘‘XANES meets ELNES’’ of the University of Antwerp. |
Approved |
Most recent IF: 4.123 |
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Call Number |
EMAT @ emat @ c:irua:140835 |
Serial |
4421 |
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Permanent link to this record |
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Author |
Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. |
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Title |
Structural and electronic properties of defects at grain boundaries in CuInSe2 |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
19 |
Issue |
19 |
Pages |
14770-14780 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect
of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at
the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported. |
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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 |
000403327200059 |
Publication Date |
2017-05-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
4.123 |
Times cited |
12 |
Open Access |
OpenAccess |
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Notes |
We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 4.123 |
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Call Number |
EMAT @ emat @ c:irua:143869 |
Serial |
4577 |
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Permanent link to this record |
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Author |
Momot, A.; Amini, M.N.; Reekmans, G.; Lamoen, D.; Partoens, B.; Slocombe, D.R.; Elen, K.; Adriaensens, P.; Hardy, A.; Van Bael, M.K. |
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Title |
A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
19 |
Issue |
40 |
Pages |
27866-27877 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A combined experimental and first-principles study is performed to study the origin of conductivity in
ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a
solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR)
and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial
positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide
evidence for the fact that the formed complex of AlZn and Zni corresponds to the origin of the Knight
shifted peak (KS) we observe in 27Al NMR. As far as we know, the role of this complex has not been
discussed in the literature to date. However, our first-principles calculations show that such a complex is
indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also
address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly
also form Zn clusters, leading to the observed increased conductivity. |
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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 |
000413290500073 |
Publication Date |
2017-10-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
26 |
Open Access |
OpenAccess |
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Notes |
We want to thank the Interuniversity Attraction Poles Programme (P7/05) initiated by the Belgian Science Policy Office (BELSPO) for the financial support. We also acknowledge the Research Foundation Flanders (FWO-Vlaanderen) for support via the MULTIMAR WOG project and under project No. G018914. The computational parts were carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules foundation and the Flemish Government (EWI Department). |
Approved |
Most recent IF: 4.123 |
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Call Number |
EMAT @ emat @c:irua:146878 |
Serial |
4760 |
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Permanent link to this record |
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Author |
Sanchez-Barriga, J.; Ogorodnikov, I.I.; Kuznetsov, M.V.; Volykhov, A.A.; Matsui, F.; Callaert, C.; Hadermann, J.; Verbitskiy, N.I.; Koch, R.J.; Varykhalov, A.; Rader, O.; Yashina, L.V. |
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Title |
Observation of hidden atomic order at the interface between Fe and topological insulator Bi2Te3 |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
19 |
Issue |
45 |
Pages |
30520-30532 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
<script type='text/javascript'>document.write(unpmarked('To realize spintronic devices based on topological insulators (TIs), well-defined interfaces between magnetic metals and TIs are required. Here, we characterize atomically precisely the interface between the 3d transition metal Fe and the TI Bi2Te3 at different stages of its formation. Using photoelectron diffraction and holography, we show that after deposition of up to 3 monolayers Fe on Bi2Te3 at room temperature, the Fe atoms are ordered at the interface despite the surface disorder revealed by our scanning-tunneling microscopy images. We find that Fe occupies two different sites: a hollow adatom deeply relaxed into the Bi2Te3 quintuple layers and an interstitial atom between the third (Te) and fourth (Bi) atomic layers. For both sites, our core-level photoemission spectra and density-functional theory calculations demonstrate simultaneous chemical bonding of Fe to both Te and Bi atoms. We further show that upon deposition of Fe up to a thickness of 20 nm, the Fe atoms penetrate deeper into the bulk forming a 2-5 nm interface layer containing FeTe. In addition, excessive Bi is pushed down into the bulk of Bi2Te3 leading to the formation of septuple layers of Bi3Te4 within a distance of similar to 25 nm from the interface. Controlling the magnetic properties of the complex interface structures revealed by our work will be of critical importance when optimizing the efficiency of spin injection in TI-based devices.')); |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000416054400023 |
Publication Date |
2017-10-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076; 1463-9084 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
4 |
Open Access |
OpenAccess |
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Notes |
; The authors acknowledge financial support within the bilateral program “Russian-German Laboratory at BESSY II” and thank Helmholtz Zentrum Berlin for granting access to the beamlines RGBL, UE112-PGM2a and U49-PGM1. The Supercomputing Center of Lomonosov Moscow State University is gratefully acknowledged for granting access to the “Lomonosov” supercomputer. The work was partially supported by DFG priority program SPP 1666, Impuls- und Vernetzungsfonds der Helmholtz-Gemeinschaft (Grant No. HRJRG-408) and Russian Foundation for Basic Research (Grants No. 13-02-91327 and No. 16-29-06410). C. C. acknowledges support from the University of Antwerp through the BOF grant 31445. The authors thank Dr Vera Neudachina, Daria Tsukanova, Dr Elmar Kataev and Dr Maria Batuk for their support during the XPS and TEM experiments. ; |
Approved |
Most recent IF: 4.123 |
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Call Number |
UA @ lucian @ c:irua:147659 |
Serial |
4888 |
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Permanent link to this record |
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Author |
Serrano-Sevillano, J.; Reynaud, M.; Saracibar, A.; Altantzis, T.; Bals, S.; van Tendeloo, G.; Casas-Cabanas, M. |
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Title |
Enhanced electrochemical performance of Li-rich cathode materials through microstructural control |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
20 |
Issue |
20 |
Pages |
23112-23122 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The microstructural complexity of Li-rich cathode materials has so far hampered understanding the critical link between size, morphology and structural defects with both capacity and voltage fadings that this family of materials exhibits. Li2MnO3 is used here as a model material to extract reliable structure–property
relationships that can be further exploited for the development of high-performing and long-lasting Li-rich oxides. A series of samples with microstructural variability have been prepared and thoroughly characterized using the FAULTS software, which allows quantification of planar defects and extraction of
average crystallite sizes. Together with transmission electron microscopy (TEM) and density functional theory (DFT) results, the successful application of FAULTS analysis to Li2MnO3 has allowed rationalizing the synthesis conditions and identifying the individual impact of concurrent microstructural features on
both voltage and capacity fadings, a necessary step for the development of high-capacity Li-ion cathode materials with enhanced cycle life. |
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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 |
000445220500071 |
Publication Date |
2018-08-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
36 |
Open Access |
OpenAccess |
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Notes |
This work was supported by the Spanish Ministerio de la Economı´a y de la Competitividad through the project IONSTORE (MINECO ref. ENE2016-81020-R). The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). JSS and AS are grateful for computing time provided by the Spanish i2Basque Centers. MR acknowledges the Spanish State for its financial support through her post-doctoral grant Juan de la Cierva – Formacio´n (MINECO ref. FJCI-2014-19990) and her international mobility grant Jose´ Castillejos (MECD ref. CAS15/00354). S. B. acknowledges funding from the European Research Council (ERC starting grant #335078 Colouratom) and T. A. a postdoctoral grant from the Research Foundation Flanders (FWO). (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ecas_sara |
Approved |
Most recent IF: 4.123 |
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Call Number |
EMAT @ emat @c:irua:154782UA @ admin @ c:irua:154782 |
Serial |
5062 |
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Permanent link to this record |
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Author |
Mefford, J.T.; Kurilovich, A.A.; Saunders, J.; Hardin, W.G.; Abakumov, A.M.; Forslund, R.P.; Bonnefont, A.; Dai, S.; Johnston, K.P.; Stevenson, K.J. |
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Title |
Decoupling the roles of carbon and metal oxides on the electrocatalytic reduction of oxygen on La1-xSrxCoO3-\delta perovskite composite electrodes |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
21 |
Issue |
6 |
Pages |
3327-3338 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Perovskite oxides are active room-temperature bifunctional oxygen electrocatalysts in alkaline media, capable of performing the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with lower combined overpotentials relative to their precious metal counterparts. However, their semiconducting nature necessitates the use of activated carbons as conductive supports to generate applicably relevant current densities. In efforts to advance the performance and theory of oxide electrocatalysts, the chemical and physical properties of the oxide material often take precedence over contributions from the conductive additive. In this work, we find that carbon plays an important synergistic role in improving the performance of La1-xSrxCoO3- (0 x 1) electrocatalysts through the activation of O-2 and spillover of radical oxygen intermediates, HO2- and O-2(-), which is further reduced through chemical decomposition of HO2- on the perovskite surface. Through a combination of thin-film rotating disk electrochemical characterization of the hydrogen peroxide intermediate reactions (hydrogen peroxide reduction reaction (HPRR), hydrogen peroxide oxidation reaction (HPOR)) and oxygen reduction reaction (ORR), surface chemical analysis, HR-TEM, and microkinetic modeling on La1-xSrxCoO3- (0 x 1)/carbon (with nitrogen and non-nitrogen doped carbons) composite electrocatalysts, we deconvolute the mechanistic aspects and contributions to reactivity of the oxide and carbon support. |
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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 |
000459584900049 |
Publication Date |
2019-01-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076; 1463-9084 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
5 |
Open Access |
OpenAccess |
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Notes |
; Financial support for this work was provided by the R. A. Welch Foundation (grants F-1529 and F-1319). S. D. was supported as part of the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences. ; |
Approved |
Most recent IF: 4.123 |
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Call Number |
UA @ admin @ c:irua:158625 |
Serial |
5244 |
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Permanent link to this record |
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Author |
Wei, H.; Hu, Z.-Y.; Xiao, Y.-X.; Tian, G.; Ying, J.; Van Tendeloo, G.; Janiak, C.; Yang, X.-Y.; Su, B.-L. |
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Title |
Control of the interfacial wettability to synthesize highly dispersed PtPd nanocrystals for efficient oxygen reduction reaction |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemistry: an Asian journal |
Abbreviated Journal |
Chem-Asian J |
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Volume |
13 |
Issue |
9 |
Pages |
1119-1123 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Highly dispersed PtPd bimetallic nanocrystals with enhanced catalytic activity and stability were prepared by adjusting the interfacial wettability of the reaction solution on a commercial carbon support. This approach holds great promise for the development of high-performance and low-cost catalysts for practical applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000431625200006 |
Publication Date |
2018-03-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1861-4728; 1861-471x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.083 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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Notes |
; This work supported by National Key R&D Program of China (2017YFC1103800), PCSIRT (IRT15R52), NSFC (U1663225, U1662134, 51472190, 51611530672, 21711530705, 51503166), ISTCP (2015DFE52870), HPNSF (2016CFA033, 2017CFB487), and Open Project Program of State Key Laboratory of Petroleum Pollution Control (Grant No. PPC2016007), CNPC Research Institute of Safety and Environmental Technology, SKLPPC. ; |
Approved |
Most recent IF: 4.083 |
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Call Number |
UA @ lucian @ c:irua:151525 |
Serial |
5018 |
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Permanent link to this record |
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Author |
Zhao, L.; Ding, L.; Soete, J.; Idrissi, H.; Kerckhofs, G.; Simar, A. |
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Title |
Fostering crack deviation via local internal stresses in Al/NiTi composites and its correlation with fracture toughness |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Composites: part A: applied science and manufacturing |
Abbreviated Journal |
Compos Part A-Appl S |
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Volume |
126 |
Issue |
126 |
Pages |
105617 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In the framework of metal matrix composites, a research gap exists regarding tailoring damage mechanisms. The present work aims at developing an Al/NiTi composite incorporating internal stresses in the vicinity of reinforcements. The composite is manufactured by friction stir processing which allows a homogenous NiTi distribution and a good Al/NiTi interface bonding. The internal stresses are introduced via shape memory effect of the embedded NiTi particles. The induced internal strain field is confirmed by digital image correlation and the corresponding stress field is evaluated by finite element simulation. It is found that the damage mechanism is modified in the presence of internal stresses. The consequent enhancement of fracture toughness arises by the fact that the internal stresses foster discrete damages shifted from the fracture ligament line. These damages release the stress concentration at the main crack tip and lead to a deviated crack path when coalescing to accommodate fracture propagation. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000489350600025 |
Publication Date |
2019-09-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1359-835x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.075 |
Times cited |
|
Open Access |
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Notes |
; This research work has been exclusively supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement no 716678). The X-ray computed,tomography facilities of the Department of Materials Engineering of the KU Leuven are financed by the Hercules Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). The authors acknowledge Professor F. Delannay from UCLouvain for fruitful discussions. ; |
Approved |
Most recent IF: 4.075 |
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Call Number |
UA @ admin @ c:irua:163706 |
Serial |
5387 |
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Permanent link to this record |
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Author |
Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J. |
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Title |
Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Dental Materials |
Abbreviated Journal |
Dent Mater |
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Volume |
32 |
Issue |
32 |
Pages |
e327-e337 |
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Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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Abstract |
OBJECTIVE: The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. METHODS: Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning electron microscopy (SEM). Translucency (n=6/group) was measured with a color meter, allowing to calculate the translucency parameter (TP) and the contrast ratio (CR). Mechanical properties were appraised with four-point bending strength (n=10), single edge V-notched beam (SEVNB) fracture toughness (n=8) and Vickers hardness (n=10). The aging stability was evaluated by measuring the tetragonal to monoclinic transformation (n=3) after accelerated hydrothermal aging in steam at 134 degrees C, and the transformation curves were fitted by the Mehl-Avrami-Johnson (MAJ) equation. Data were analyzed by one-way ANOVA, followed by Tukey's HSD test (alpha=0.05). RESULTS: Lowering the alumina content below 0.25wt.% avoided the formation of alumina particles and therefore increased the translucency of 3Y-TZP ceramics, but the hydrothermal aging stability was reduced. A higher yttria content (5mol%) introduced about 50% cubic zirconia phase and gave rise to the most translucent and aging-resistant Y-TZP ceramics, but the fracture toughness and strength were considerably sacrificed. 0.2mol% La2O3 doping of 3Y-TZP tailored the grain boundary chemistry and significantly improved the aging resistance and translucency. Although the translucency improvement by La2O3 doping was less effective than for introducing a substantial amount of cubic zirconia, this strategy was able to maintain the mechanical properties of typical 3Y-TZP ceramics. SIGNIFICANCE: Three different approaches were compared to improve the translucency of 3Y-TZP ceramics. |
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Address |
KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, Belgium |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000389516400003 |
Publication Date |
2016-10-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0109-5641 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.07 |
Times cited |
|
Open Access |
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Notes |
The authors acknowledge the Research Fund of KU Leu- ven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post- doctoral fellowship (PDM/15/153). We thank M. Peumans for the translucency measurements. |
Approved |
Most recent IF: 4.07 |
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|
Call Number |
EMAT @ emat @ c:irua:136821 |
Serial |
4313 |
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Permanent link to this record |
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Author |
Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J. |
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Title |
Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Dental materials |
Abbreviated Journal |
Dent Mater |
|
|
Volume |
32 |
Issue |
12 |
Pages |
E327-E337 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Objective. The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. Methods. Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning electron microscopy (SEM). Translucency (n = 6/group) was measured with a color meter, allowing to calculate the translucency parameter (TP) and the contrast ratio (CR). Mechanical properties were appraised with four-point bending strength (n = 10), single edge V-notched beam (SEVNB) fracture toughness (n = 8) and Vickers hardness (n = 10). The aging stability was evaluated by measuring the tetragonal to monoclinic transformation (n = 3) after accelerated hydrothermal aging in steam at 134 degrees C, and the transformation curves were fitted by the Mehl-Avrami-Johnson (MAJ) equation. Data were analyzed by one-way ANOVA, followed by Tukey's HSD test (alpha = 0.05). Results. Lowering the alumina content below 0.25 wt.% avoided the formation of alumina particles and therefore increased the translucency of 3Y-TZP ceramics, but the hydrothermal aging stability was reduced. A higher yttria content (5 mol%) introduced about 50% cubic zirconia phase and gave rise to the most translucent and aging-resistant Y-TZP ceramics, but the fracture toughness and strength were considerably sacrificed. 0.2 mol% La2O3 doping of 3Y-TZP tailored the grain boundary chemistry and significantly improved the aging resistance and translucency. Although the translucency improvement by La2O3 doping was less effective than for introducing a substantial amount of cubic zirconia, this strategy was able to maintain the mechanical properties of typical 3Y-TZP ceramics. Significance. Three different approaches were compared to improve the translucency of 3YTZP ceramics. (C) 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Copenhagen |
Editor |
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Language |
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Wos |
000389516400003 |
Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0109-5641 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4.07 |
Times cited |
47 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.07 |
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Call Number |
UA @ lucian @ c:irua:140246 |
Serial |
4447 |
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Permanent link to this record |
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Author |
Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. |
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Title |
Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
10 |
Issue |
4 |
Pages |
2011-2018 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000276234500080 |
Publication Date |
2010-03-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
75 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
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Call Number |
UA @ lucian @ c:irua:82311 |
Serial |
1472 |
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Permanent link to this record |
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Author |
Li, Y.; Tan, H.; Lebedev, O.; Verbeeck, J.; Biermans, E.; Van Tendeloo, G.; Su, B.-L. |
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Title |
Insight into the growth of multiple branched MnOOH nanorods |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
10 |
Issue |
7 |
Pages |
2969-2976 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Multiple branched manganese oxide hydroxide (MnOOH) nanorods prepared by a hydrothermal process were extensively studied by transmission electron microscopy (TEM). A model of the branch formation is proposed together with a study of the interface structure. The sword-like tip plays a crucial role for the nanorods to form different shapes. Importantly, the branching occurs at an angle of around either 57 degrees or 123 degrees. Specifically, a (111) twin plane can only be formed at the interface with a 123 degrees angle. The interfaces formed with a 57 degrees angle usually contain edge dislocations. Electron energy loss spectroscopy (EELS) demonstrates that the whole crystal has a uniform chemical composition. Interestingly, an epitaxial growth of Mn3O4 at the radial surface was also observed under electron beam irradiation; this is because of the rough purification of the products. The proposed mechanism is expected to shed light on the branched/dendrite nanostructure growth and to provide opportunities for further novel nanomaterial structure growth and design. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000279422700027 |
Publication Date |
2010-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
41 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
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Call Number |
UA @ lucian @ c:irua:83886UA @ admin @ c:irua:83886 |
Serial |
1672 |
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Permanent link to this record |
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Author |
Barreca, D.; Gasparotto, A.; Maccato, C.; Tondello, E.; Lebedev, O.I.; Van Tendeloo, G. |
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Title |
CVD of copper oxides from a \beta-diketonate diamine precursor: tailoring the nano-organization |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
9 |
Issue |
5 |
Pages |
2470-2480 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A copper(II) hexafluoroacetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate, hfa) adduct with N,N,N¡ä,N¡ä-tetramethylethylenediamine (TMEDA) [Cu(hfa)2¡¤TMEDA] is used for the first time as precursor for the chemical vapor deposition (CVD) of copper oxide nanosystems. The syntheses are carried out under both O2 and O2+H2O reaction atmospheres on Si(100) substrates, at temperatures ranging between 250 and 550 ¡ãC. Subsequently, the interrelations between the preparative conditions and the system composition, nanostructure, and morphology are elucidated by means of complementary analytical techniques [Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron and X-ray excited auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM)]. The obtained data revealed a gradual transformation from Cu2O, to Cu2O + CuO, to CuO nanosystems upon increasing the deposition temperature from 250 to 550 ¡ãC under both growth atmospheres. Such a phenomenon was accompanied by a progressive morphological evolution from continuous films to 1D hyperbranched nanostructures. Water vapor introduction in the deposition environment enabled to lower the deposition temperature and resulted in a higher aggregate interconnection, attributed to a higher density of nucleation centers. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000265892200066 |
Publication Date |
2009-05-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
60 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
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Call Number |
UA @ lucian @ c:irua:77053 |
Serial |
597 |
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Permanent link to this record |
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Author |
Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Guitián, F.; Yoshimura, M. |
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Title |
An effective morphology control of hydroxyapatite crystals via hydrothermal synthesis |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
9 |
Issue |
1 |
Pages |
466-474 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A facile urea-assisted hydrothermal synthesis and systematic characterization of hydroxyapatite (HA) with calcium nitrate tetrahydrate and diammonium hydrogen phosphate as precursors are reported. The advantage of the proposed technique over previously reported synthetic approaches is the simple but precise control of the HA crystals morphology, which is achieved by employing an intensive, stepwise, and slow thermal decomposition of urea as well as varying initial concentrations of starting reagents. Whereas the plate-, hexagonal prism- and needle-like HA particles preferentially growth along the c-axis, the smaller and fine-plate-like HA crystals demonstrate crystal growth along the (102) and (211) directions, uncommon for HA. Furthermore, it was established that the hydrothermally derived powdered products are phase-pure HA containing CO32− anions in the crystal lattice, that is, AB-type carbonated hydroxyapatite. Transmission electron microscopy (TEM) and electron diffraction (ED) of selected samples reveal that the as-prepared HA crystals are single-crystalline and exhibit a nearly defect-free microstructure. The hardness and elastic modulus of the hexagonal prism-like HA crystals have been investigated on a nanoscale using the nanoindentation technique; the observed trends are discussed. |
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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 |
000262332700073 |
Publication Date |
2008-11-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
183 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
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Call Number |
UA @ lucian @ c:irua:75740 |
Serial |
853 |
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Permanent link to this record |
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Author |
Hoang, D.-Q.; Pobedinskas, P.; Nicley, S.S.; Turner, S.; Janssens, S.D.; Van Bael, M.K.; D'Haen, J.; Haenen, K. |
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Title |
Elucidation of the Growth Mechanism of Sputtered 2D Hexagonal Boron Nitride Nanowalls |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
16 |
Issue |
7 |
Pages |
3699-3708 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Hexagonal boron nitride nanowall thin films were deposited on Si(100) substrates using a Ar(51%)/N-2(44%)/H-2(5%) gas mixture by unbalanced radio frequency sputtering. The effects of various target-to-substrate distances, substrate temperatures, and substrate tilting angles were investigated. When the substrate is close to the target, hydrogen etching plays a significant role in the film growth, while the effect is negligible for films deposited at a farther distance. The relative quantity of defects was measured by a non-destructive infrared spectroscopy technique that characterized the hydrogen incorporation at dangling nitrogen bonds at defect sites in the deposited films. Despite the films deposited at different substrate tilting angles, the nanowalls of those films were found to consistently grow vertical to the substrate surface, independent of the tilting angle. This implies that chemical processes, rather than physical ones, govern the growth of the nanowalls. The results also reveal that the degree of nanowall crystallization is tunable by varying the growth parameters. Finally, evidence of hydrogen desorption during vacuum annealing is given based on measurements of infrared stretching (E-1u) and bending (A(2u)) modes of the optical phonons, and the H-N vibration mode. |
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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 |
000379456700020 |
Publication Date |
2016-05-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.055 |
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Call Number |
UA @ lucian @ c:irua:144690 |
Serial |
4652 |
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Permanent link to this record |
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Author |
Drijkoningen, S.; Pobedinskas, P.; Korneychuk, S.; Momot, A.; Balasubramaniam, Y.; Van Bael, M.K.; Turner, S.; Verbeeck, J.; Nesladekt, M.; Haenen, K. |
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Title |
On the Origin of Diamond Plates Deposited at Low Temperature |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
17 |
Issue |
8 |
Pages |
4306-4314 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The crucial requirement for diamond growth at low temperatures, enabling a wide range of new applications, is a high plasma density at a low gas pressure, which leads to a low thermal load onto sensitive substrate materials. While these conditions are not within reach for resonance cavity plasma systems, linear antenna microwave delivery systems allow the deposition of high quality diamond films at temperatures around 400 degrees C and at pressures below 1 mbar. In this work the codeposition of high quality plates and octahedral diamond grains in nanocrystalline films is reported. In contrast to previous reports claiming the need for high temperatures (T >= 850 degrees C), low temperatures (320 degrees C <= T <= 410 degrees C) were sufficient to deposit diamond plate structures. Cross-sectional high resolution transmission electron microscopy studies show that these plates are faulty cubic diamond terminated by large {111} surface facets with very little sp(2) bonded carbon in the grain boundaries. Raman and electron energy loss spectroscopy studies confirm a high diamond quality, above 93% sp(3) carbon content. Three potential mechanisms, that can account for the initial development of the observed plates rich with stacking faults, and are based on the presence of impurities, are proposed. |
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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 |
000407089600031 |
Publication Date |
2017-06-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
23 |
Open Access |
Not_Open_Access |
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Notes |
; The Research Foundation – Flanders (FWO) is gratefully acknowledged for financial support in the form of the Postdoctoral Fellowships of P.P. and S.T., contract G.0044.13N “Charge ordering” (S.K., J.V.), the Methusalem “Nano” network, and the Hercules-linear antenna and Raman equipment. ; |
Approved |
Most recent IF: 4.055 |
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Call Number |
UA @ lucian @ c:irua:145735UA @ admin @ c:irua:145735 |
Serial |
4746 |
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Permanent link to this record |
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Author |
Barreca, D.; Carraro, G.; Maccato, C.; Altantzis, T.; Kaunisto, K.; Gasparotto, A. |
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Title |
Controlled Growth of Supported ZnO Inverted Nanopyramids with Downward Pointing Tips |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
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Issue |
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Pages |
acs.cgd.8b00198 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
High purity porous ZnO nanopyramids with controllable properties are grown on their tips on
Si(100) substrates by means of a catalyst-free vapor phase deposition route in a wet oxygen
reaction environment. The system degree of preferential [001] orientation, as well as
nanopyramid size, geometrical shape and density distribution, can be finely tuned by varying the
growth temperature between 300 and 400°C, whereas higher temperatures lead to more compact
systems with a three-dimensional (3D) morphology. A growth mechanism of the obtained ZnO
nanostructures based on a self-catalytic vapor-solid (VS) mode is proposed, in order to explain
the evolution of nanostructure morphologies as a function of the adopted process conditions. The
results obtained by a thorough chemico-physical characterization enable to get an improved
control over the properties of ZnO nanopyramids grown by this technique. Taken together, they
are of noticeable importance not only for fundamental research on ZnO nanomaterials with
controlled nano-organization, but also to tailor ZnO functionalities in view of various potential
applications. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000429508200073 |
Publication Date |
2018-03-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
6 |
Open Access |
OpenAccess |
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Notes |
This work has been supported by Padova University ex-60% 2015–2017, P-DiSC #03BIRD2016-UNIPD projects and ACTION post-doc fellowship. T. A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). Thanks are also due to Dr. Rosa Calabrese (Department of Chemical Sciences, Padova University, Italy) and to Dr. T.-P. Ruoko (Department of Chemistry and Bioengineering, Tampere University of Technology, Finland) for skilful technical support. |
Approved |
Most recent IF: 4.055 |
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Call Number |
EMAT @ emat @c:irua:149514 |
Serial |
4904 |
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Permanent link to this record |
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Author |
García-Sánchez, C.; Philips, D.A.; Gorlé, C. |
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Title |
Quantifying inflow uncertainties for CFD simulations of the flow in downtown Oklahoma City |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Building and environment |
Abbreviated Journal |
Build Environ |
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Volume |
78 |
Issue |
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Pages |
118-129 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Computational Fluid Dynamics (CFD) methods are widely used to investigate wind flow and dispersion in urban environments. Validation with field experiments that represent the full complexity of the problem should be performed to assess the predictive capabilities of the computations. In this context it will be necessary to quantify the effect of uncertainties in simulations of the full-scale problem. The present study aims at quantifying the uncertainty related to the variability in the inflow boundary conditions for Reynolds-averaged Navier-Stokes (RANS) simulations of the flow in downtown Oklahoma City to address validation with the Joint Urban 2003 field measurements. Three uncertain inflow parameters were defined: the wind speed and wind direction at a reference height, and the aerodynamic roughness in the logarithmic velocity inlet profile. An ensemble of 729 RANS simulations were performed to determine the polynomial chaos expansion coefficients that define the response surfaces for the velocity magnitude and direction at 13 field measurement stations, and the results are compared to the experimental data. For the velocity magnitude the mean experimental velocity magnitude is encompassed within the 95% confidence interval for the magnitudes predicted by the Uncertainty Quantification study in all stations. For the velocity direction this holds in 11 out of 13 locations. The study demonstrates the significant potential of applying advanced uncertainty quantification methods to address validation with field measurements and to develop a more realistic approach to the definition of inflow boundary conditions in atmospheric CFD simulations. (C) 2014 Elsevier Ltd. All rights reserved. |
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Place of Publication |
Oxford |
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Wos |
000338619700013 |
Publication Date |
2014-05-02 |
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ISSN |
0360-1323; |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.053 |
Times cited |
29 |
Open Access |
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Approved |
Most recent IF: 4.053; 2014 IF: 3.341 |
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Call Number |
UA @ lucian @ c:irua:118632 |
Serial |
2742 |
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Author |
Wang, C.; Xin, X.; Shu, M.; Huang, S.; Zhang, Y.; Li, X. |
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Title |
Scalable synthesis of one-dimensional Na2Li2Ti6O14 nanofibers as ultrahigh rate capability anodes for lithium-ion batteries |
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A1 Journal article |
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Year |
2019 |
Publication |
Inorganic Chemistry Frontiers |
Abbreviated Journal |
Inorg Chem Front |
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Volume |
6 |
Issue |
3 |
Pages |
646-653 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Carbon anode materials for Li-ion batteries have been operated close to their theoretical rate and cycle limits. Therefore, titanium-based materials have attracted great attention due to their high stability. Here, Na2Li2Ti6O14 nanofibers as anode materials were prepared through a controlled electrospinning method. The Na2Li2Ti6O14 nanofibers presented superior electrochemical performance with high rate capability and long cycle life and can be regarded as a competitive anode candidate for advanced Li-ion batteries. One-dimensional (1D) Na2Li2Ti6O14 nanofibers are able to deliver a capacity of 128.5 mA h g(-1) at 0.5C, and demonstrate superior high-rate charge-discharge capability and cycling stability (the reversible charge capacity is 77.8 mA h g(-1) with a capacity retention of 99.45% at the rate of 10C after 800 cycles). The 1D structure is considered to contribute remarkably to increased rate capability and stability. This simple and scalable method indicates that the Na2Li2Ti6O14 nanofibers have a practical application potential for high performance lithium-ion batteries. |
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000461092500027 |
Publication Date |
2018-11-17 |
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ISSN |
2052-1553 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.036 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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Notes |
; The authors acknowledge financial support from the National Natural Science Foundation of China (21571110), Natural Science Foundation of Zhejiang Province (LY18B010003), and the Ningbo Key Innovation Team (2014B81005), and sponsorship by the K.C. Wong Magna Fund in Ningbo University. ; |
Approved |
Most recent IF: 4.036 |
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Call Number |
UA @ admin @ c:irua:158566 |
Serial |
5258 |
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