Records |
Author |
De Henau, S.; Tilleman, L.; Vangheel, M.; Luyckx, E.; Trashin, S.; Pauwels, M.; Germani, F.; Vlaeminck, C.; Vanfleteren, J.R.; Bert, W.; Pesce, A.; Nardini, M.; Bolognesi, M.; De Wael, K.; Moens, L.; Dewilde, S.; Braeckman, B.P. |
Title |
A redox signalling globin is essential for reproduction in Caenorhabditis elegans |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
6 |
Issue |
|
Pages |
8782 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Moderate levels of reactive oxygen species (ROS) are now recognized as redox signalling molecules. However, thus far, only mitochondria and NADPH oxidases have been identified as cellular sources of ROS in signalling. Here we identify a globin (GLB-12) that produces superoxide, a type of ROS, which serves as an essential signal for reproduction in C. elegans. We find that GLB-12 has an important role in the regulation of multiple aspects in germline development, including germ cell apoptosis. We further describe how GLB-12 displays specific molecular, biochemical and structural properties that allow this globin to act as a superoxide generator. In addition, both an intra- and extracellular superoxide dismutase act as key partners of GLB-12 to create a transmembrane redox signal. Our results show that a globin can function as a driving factor in redox signalling, and how this signal is regulated at the subcellular level by multiple control layers. |
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 |
000367577100002 |
Publication Date |
2015-12-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
20 |
Open Access |
|
Notes |
; We thank Dr K. Matsumoto and Dr T. Mizuno for kindly providing the mek-1(ks54) sek-1(km4) double mutant, the antibody anti-PMK-1 and technical advice on antibody use; Dr D. Kim for kindly providing the pDK177 RNAi strain; Dr M. Ubbink and Dr Q. Bashir for providing CCP; Dr K. Oegema and the OD lab for sharing technical expertise; M. Couvreur for assistance in generating transgenic lines; and Dr T. Dansen for the final support. Some strains were provided by the CGC, which is funded by the NIH Office of Research Infrastructure Programs (P40 OD010440). S.D.H. and F.G. are PhD fellows of the Fund for Scientific Research (FWO). Financial support to S.D. and L.M. was provided by the University of Antwerp (BOF UA TOP 2006), to K.D.W., S.D. and S.T. by the University of Antwerp (BOF-GOA) and to S.D., L.M., B.P.B., by FWO project G.0247.09. ; |
Approved |
Most recent IF: 12.124; 2015 IF: 11.470 |
Call Number |
UA @ admin @ c:irua:129310 |
Serial |
5809 |
Permanent link to this record |
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|
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Author |
Sathiya, M.; Abakumov, A.M.; Foix, D.; Rousse, G.; Ramesha, K.; Saubanère, M.; Doublet, M. .; Vezin, H.; Laisa, C.P.; Prakash, A.S.; Gonbeau, D.; Van Tendeloo, G.; Tarascon, J.M. |
Title |
Origin of voltage decay in high-capacity layered oxide electrodes |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
Volume |
14 |
Issue |
14 |
Pages |
230-238 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Although Li-rich layered oxides (Li1+xNiyCozMn1−x−y−zO2 > 250 mAh g−1) are attractive electrode materials providing energy densities more than 15% higher than todays commercial Li-ion cells, they suffer from voltage decay on cycling. To elucidate the origin of this phenomenon, we employ chemical substitution in structurally related Li2RuO3 compounds. Li-rich layered Li2Ru1−yTiyO3 phases with capacities of ~240 mAh g−1 exhibit the characteristic voltage decay on cycling. A combination of transmission electron microscopy and X-ray photoelectron spectroscopy studies reveals that the migration of cations between metal layers and Li layers is an intrinsic feature of the chargedischarge process that increases the trapping of metal ions in interstitial tetrahedral sites. A correlation between these trapped ions and the voltage decay is established by expanding the study to both Li2Ru1−ySnyO3 and Li2RuO3; the slowest decay occurs for the cations with the largest ionic radii. This effect is robust, and the finding provides insights into new chemistry to be explored for developing high-capacity layered electrodes that evade voltage decay. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000348600200024 |
Publication Date |
2014-12-01 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
39.737 |
Times cited |
395 |
Open Access |
|
Notes |
246791 Countatoms; 312483 Esteem2; esteem2_ta |
Approved |
Most recent IF: 39.737; 2015 IF: 36.503 |
Call Number |
c:irua:132555 c:irua:132555 |
Serial |
2528 |
Permanent link to this record |
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Author |
Chen, Y.Z.; Trier, F.; Wijnands, T.; Green, R.J.; Gauquelin, N.; Egoavil, R.; Christensen, D.V.; Koster, G.; Huijben, M.; Bovet, N.; Macke, S.; He, F.; Sutarto, R.; Andersen, N.H.; Sulpizio, J.A.; Honig, M.; Prawiroatmodjo, G.E.D.K.; Jespersen, T.S.; Linderoth, S.; Ilani, S.; Verbeeck, J.; Van Tendeloo, G.; Rijnders, G.; Sawatzky, G.A.; Pryds, N. |
Title |
Extreme mobility enhancement of two-dimensional electron gases at oxide interfaces by charge-transfer-induced modulation doping |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
Volume |
14 |
Issue |
14 |
Pages |
801-806 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Two-dimensional electron gases (2DEGs) formed at the interface of insulating complex oxides promise the development of all-oxide electronic devices. These 2DEGs involve many-body interactions that give rise to a variety of physical phenomena such as superconductivity, magnetism, tunable metalinsulator transitions and phase separation. Increasing the mobility of the 2DEG, however, remains a major challenge. Here, we show that the electron mobility is enhanced by more than two orders of magnitude by inserting a single-unit-cell insulating layer of polar La1−xSrxMnO3 (x = 0, 1/8, and 1/3) at the interface between disordered LaAlO3 and crystalline SrTiO3 produced at room temperature. Resonant X-ray spectroscopy and transmission electron microscopy show that the manganite layer undergoes unambiguous electronic reconstruction, leading to modulation doping of such atomically engineered complex oxide heterointerfaces. At low temperatures, the modulation-doped 2DEG exhibits Shubnikovde Haas oscillations and fingerprints of the quantum Hall effect, demonstrating unprecedented high mobility and low electron density. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000358530100022 |
Publication Date |
2015-06-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
39.737 |
Times cited |
170 |
Open Access |
|
Notes |
246102 IFOX; 246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; FWO G004413N; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 39.737; 2015 IF: 36.503 |
Call Number |
c:irua:127184 c:irua:127184UA @ admin @ c:irua:127184 |
Serial |
1163 |
Permanent link to this record |
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Author |
da Silva, R.M.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M.; Albino Aguiar, J. |
Title |
Giant paramagnetic Meissner effect in multiband superconductors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
5 |
Issue |
5 |
Pages |
12695 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Superconductors, ideally diamagnetic when in the Meissner state, can also exhibit paramagnetic behavior due to trapped magnetic flux. In the absence of pinning such paramagnetic response is weak, and ceases with increasing sample thickness. Here we show that in multiband superconductors paramagnetic response can be observed even in slab geometries, and can be far larger than any previous estimate – even multiply larger than the diamagnetic Meissner response for the same applied magnetic field. We link the appearance of this giant paramagnetic response to the broad crossover between conventional Type-I and Type-II superconductors, where Abrikosov vortices interact non-monotonically and multibody effects become important, causing unique flux configurations and their locking in the presence of surfaces. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
Language |
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Wos |
000359143700001 |
Publication Date |
2015-08-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
25 |
Open Access |
|
Notes |
; This work was supported by the Brazilian science agencies CAPES (PNPD 223038.003145/2011-00), CNPq (307552/2012-8, 141911/2012-3, and APV-4 02937/ 2013-9), and FACEPE (APQ-0202-1.05/10 and BCT-0278-1.05/11), the Flemish Science Foundation (FWO-Vl), and by the CNPq-FWO cooperation programme (CNPq 490297/2009-9). R.M.S. acknowledges support from the SRS PhD+ program of the University Cooperation for Development of the Flemish Interuniversity Council (VLIR-UOS). M.V.M. acknowledges support from CNPq (APV-4 02937/2013-9), FACEPE (APV-0034-1.05/14), and CAPES (BEX1392/11-5). ; |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
Call Number |
c:irua:127212 |
Serial |
1339 |
Permanent link to this record |
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Author |
Tang, X.; Reckinger, N.; Poncelet, O.; Louette, P.; Urena, F.; Idrissi, H.; Turner, S.; Cabosart, D.; Colomer, J.-F.; Raskin, J.-P.; Hackens, B.; Francis, L.A. |
Title |
Damage evaluation in graphene underlying atomic layer deposition dielectrics |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
5 |
Issue |
5 |
Pages |
13523 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Based on micro-Raman spectroscopy (muRS) and X-ray photoelectron spectroscopy (XPS), we study the structural damage incurred in monolayer (1L) and few-layer (FL) graphene subjected to atomic-layer deposition of HfO2 and Al2O3 upon different oxygen plasma power levels. We evaluate the damage level and the influence of the HfO2 thickness on graphene. The results indicate that in the case of Al2O3/graphene, whether 1L or FL graphene is strongly damaged under our process conditions. For the case of HfO2/graphene, muRS analysis clearly shows that FL graphene is less disordered than 1L graphene. In addition, the damage levels in FL graphene decrease with the number of layers. Moreover, the FL graphene damage is inversely proportional to the thickness of HfO2 film. Particularly, the bottom layer of twisted bilayer (t-2L) has the salient features of 1L graphene. Therefore, FL graphene allows for controlling/limiting the degree of defect during the PE-ALD HfO2 of dielectrics and could be a good starting material for building field effect transistors, sensors, touch screens and solar cells. Besides, the formation of Hf-C bonds may favor growing high-quality and uniform-coverage dielectric. HfO2 could be a suitable high-K gate dielectric with a scaling capability down to sub-5-nm for graphene-based transistors. |
Address |
ICTEAM Institute, Universite catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium |
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 |
000360147400001 |
Publication Date |
2015-08-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
18 |
Open Access |
|
Notes |
The authors thank the staff of UCL’s Winfab and Welcome for technical support. Xiaohui Tang is a senior research of UCL. This work is financially supported by the Multi-Sensor-Platform for Smart Building Management project (No. 611887) and the Action de Recherche Concertée (ARC) “StressTronics”, Communauté française de Belgique. Part of this work is financially supported by the Belgian Fund for Scientific Research (FRS-FNRS) under FRFC contract “Chemographene” (No. 2.4577.11). J.-F. Colomer and B. Hackens are Research Associates of FRS-FNRS. This research used resources of the Electron Microscopy Service located at the University of Namur (“Plateforme Technologique Morphologie – Imagerie”). This research used resources of the ELISE Service of the University of Namur. This Service is member of the “Plateforme Technologique SIAM”. The research leading to this work has received partial funding from the European Union Seventh Framework Program under grant agreement No 604391 Graphene Flagship. |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
Call Number |
c:irua:129193 |
Serial |
3958 |
Permanent link to this record |
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Author |
Hoon Park, J.; Kumar, N.; Hoon Park, D.; Yusupov, M.; Neyts, E.C.; Verlackt, C.C.W.; Bogaerts, A.; Ho Kang, M.; Sup Uhm, H.; Ha Choi, E.; Attri, P.; |
Title |
A comparative study for the inactivation of multidrug resistance bacteria using dielectric barrier discharge and nano-second pulsed plasma |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
5 |
Issue |
5 |
Pages |
13849 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Bacteria can be inactivated through various physical and chemical means, and these have always been the focus of extensive research. To further improve the methodology for these ends, two types of plasma systems were investigated: nano-second pulsed plasma (NPP) as liquid discharge plasma and an Argon gas-feeding dielectric barrier discharge (Ar-DBD) as a form of surface plasma. To understand the sterilizing action of these two different plasma sources, we performed experiments with Staphylococcus aureus (S. aureus) bacteria (wild type) and multidrug resistant bacteria (Penicillum-resistant, Methicillin-resistant and Gentamicin-resistant). We observed that both plasma sources can inactivate both the wild type and multidrug-resistant bacteria to a good extent. Moreover, we observed a change in the surface morphology, gene expression and β-lactamase activity. Furthermore, we used X-ray photoelectron spectroscopy to investigate the variation in functional groups (C-H/C-C, C-OH and C=O) of the peptidoglycan (PG) resulting from exposure to plasma species. To obtain atomic scale insight in the plasma-cell interactions and support our experimental observations, we have performed molecular dynamics simulations to study the effects of plasma species, such as OH, H2O2, O, O3, as well as O2 and H2O, on the dissociation/formation of above mentioned functional groups in PG. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000360909000001 |
Publication Date |
2015-09-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
32 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
Call Number |
c:irua:127410 |
Serial |
419 |
Permanent link to this record |
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Author |
Jelić, Ž.L.; Milošević, M.V.; Van de Vondel, J.; Silhanek, A.V. |
Title |
Stroboscopic phenomena in superconductors with dynamic pinning landscape |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
5 |
Issue |
5 |
Pages |
14604 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Introducing artificial pinning centers is a well established strategy to trap quantum vortices and increase the maximal magnetic field and applied electric current that a superconductor can sustain without dissipation. In case of spatially periodic pinning, a clear enhancement of the superconducting critical current arises when commensurability between the vortex configurations and the pinning landscape occurs. With recent achievements in (ultrafast) optics and nanoengineered plasmonics it has become possible to exploit the interaction of light with superconductivity, and create not only spatially periodic imprints on the superconducting condensate, but also temporally periodic ones. Here we show that in the latter case, temporal matching phenomena develop, caused by stroboscopic commensurability between the characteristic frequency of the vortex motion under applied current and the frequency of the dynamic pinning. The matching resonances persist in a broad parameter space, including magnetic field, driving current, or material purity, giving rise to unusual features such as externally variable resistance/impedance and Shapiro steps in current-voltage characteristics. All features are tunable by the frequency of the dynamic pinning landscape. These findings open further exploration avenues for using flashing, spatially engineered, and/or mobile excitations on superconductors, permitting us to achieve advanced functionalities. |
Address |
Departement de Physique, Universite de Liege, Allee du 6-Aout 17, B-4000 Liege, Belgium |
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 |
000362082500001 |
Publication Date |
2015-10-01 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
29 |
Open Access |
|
Notes |
Acknowledgements: This work was supported by the Methusalem Funding of the Flemish Government, the Research Foundation-Flanders (FWO) and the COST Action MP1201. The work of Ž.L.J. and A.V.S. was partially supported by “Mandat d’Impulsion Scientifique” of the F.R.S.-FNRS. |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
Call Number |
c:irua:129807 c:irua:129807 |
Serial |
3980 |
Permanent link to this record |
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Author |
Curran, P.J.; Desoky, W.M.; Milošević, M.V.; Chaves, A.; Laloe, J.-B.; Moodera, J.S.; Bending, S.J. |
Title |
Spontaneous symmetry breaking in vortex systems with two repulsive lengthscales |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
5 |
Issue |
5 |
Pages |
15569 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Scanning Hall probe microscopy (SHPM) has been used to study vortex structures in thin epitaxial films of the superconductor MgB2. Unusual vortex patterns observed in MgB2 single crystals have previously been attributed to a competition between short-range repulsive and long-range attractive vortex-vortex interactions in this two band superconductor; the type 1.5 superconductivity scenario. Our films have much higher levels of disorder than bulk single crystals and therefore both superconducting condensates are expected to be pushed deep into the type 2 regime with purely repulsive vortex interactions. We observe broken symmetry vortex patterns at low fields in all samples after field-cooling from above T-c. These are consistent with those seen in systems with competing repulsions on disparate length scales, and remarkably similar structures are reproduced in dirty two band Ginzburg-Landau calculations, where the simulation parameters have been defined by experimental observations. This suggests that in our dirty MgB2 films, the symmetry of the vortex structures is broken by the presence of vortex repulsions with two different lengthscales, originating from the two distinct superconducting condensates. This represents an entirely new mechanism for spontaneous symmetry breaking in systems of superconducting vortices, with important implications for pinning phenomena and high current density applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000363306000002 |
Publication Date |
2015-10-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
12 |
Open Access |
|
Notes |
; P.J.C. and S.J.B. acknowledge support from EPSRC in the UK under grant number EP/J010626/1 and the NanoSC COST Action MP-1201. M.V.M. thanks the Research Foundation-Flanders (FWO) and CAPES Brazil. A.C. acknowledges the financial support of CNPq, under the PRONEX/FUNCAP and PQ programs. J.-B.L. and J.S.M. acknowledge ONR Grant N00014-06-01-0235. ; |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
Call Number |
UA @ lucian @ c:irua:129450 |
Serial |
4248 |
Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
Title |
Phonon limited superconducting correlations in metallic nanograins |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
5 |
Issue |
5 |
Pages |
16515 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Conventional superconductivity is inevitably suppressed in ultra-small metallic grains for characteristic sizes smaller than the Anderson limit. Experiments have shown that above the Anderson limit the critical temperature may be either enhanced or reduced when decreasing the particle size, depending on the superconducting material. In addition, there is experimental evidence that whether an enhancement or a reduction is found depends on the strength of the electronphonon interaction in the bulk. We reveal how the strength of the e-ph interaction interplays with the quantum-size effect and theoretically obtain the critical temperature of the superconducting nanograins in excellent agreement with experimental data. We demonstrate that strong e-ph scattering smears the peak structure in the electronic density-of-states of a metallic grain and enhances the electron mass, and thereby limits the highest T-c achievable by quantum confinement. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000364647700001 |
Publication Date |
2015-11-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Research Foundation Flanders (FWO), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO. M.D.C. acknowledges fruitful discussions with V. Z. Kresin, S. N. Klimin and V. N. Gladilin. ; |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
Call Number |
UA @ lucian @ c:irua:129543 |
Serial |
4224 |
Permanent link to this record |
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Author |
Yalcin, A.O.; Goris, B.; van Dijk-Moes, R.J.A.; Fan, Z.; Erdamar, A.K.; Tichelaar, F.D.; Vlugt, T.J.H.; Van Tendeloo, G.; Bals, S.; Vanmaekelbergh, D.; Zandbergen, H.W.; van Huis, M.A.; |
Title |
Heat-induced transformation of CdSe-CdS-ZnS coremultishell quantum dots by Zn diffusion into inner layers |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Chemical communications |
Abbreviated Journal |
Chem Commun |
Volume |
51 |
Issue |
51 |
Pages |
3320-3323 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In this work, we investigate the thermal evolution of CdSeCdSZnS coremultishell quantum dots (QDs) in situ using transmission electron microscopy (TEM). Starting at a temperature of approximately 250 °C, Zn diffusion into inner layers takes place together with simultaneous evaporation of particularly Cd and S. As a result of this transformation, CdxZn1−xSeCdyZn1−yS coreshell QDs are obtained. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000349325000004 |
Publication Date |
2014-11-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1359-7345;1364-548X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.319 |
Times cited |
21 |
Open Access |
OpenAccess |
Notes |
262348 Esmi; Fwo; 246791 Countatoms; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 6.319; 2015 IF: 6.834 |
Call Number |
c:irua:132582 |
Serial |
1412 |
Permanent link to this record |
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|
Author |
Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. |
Title |
The role of the VZn-NO-H complex in the p-type conductivity in ZnO |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
17 |
Issue |
17 |
Pages |
5485-5489 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000349616400080 |
Publication Date |
2015-01-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
20 |
Open Access |
|
Notes |
FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules |
Approved |
Most recent IF: 4.123; 2015 IF: 4.493 |
Call Number |
c:irua:123218 |
Serial |
3592 |
Permanent link to this record |
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|
Author |
Lin, F.; Meng; Kukueva, E.; Altantzis, T.; Mertens, M.; Bals, S.; Cool, P.; Van Doorslaer, S. |
Title |
Direct-synthesis method towards copper-containing periodic mesoporous organosilicas : detailed investigation of the copper distribution in the material |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
44 |
Issue |
44 |
Pages |
9970-9979 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Three-dimensional cubic Fm (3) over barm mesoporous copper-containing ethane-bridged PMO materials have been prepared through a direct-synthesis method at room temperature in the presence of cetyltrimethylammonium bromide as surfactant. The obtained materials have been unambiguously characterized in detail by several sophisticated techniques, including XRD, UV-Vis-Dr, TEM, elemental mapping, continuous- wave and pulsed EPR spectroscopy. The results show that at lower copper loading, the Cu2+ species are well dispersed in the Cu-PMO materials, and mainly exist as mononuclear Cu2+ species. At higher copper loading amount, Cu2+ clusters are observed in the materials, but the distribution of the Cu2+ species is still much better in the Cu-PMO materials prepared through the direct-synthesis method than in a Cu-containing PMO material prepared through an impregnation method. Moreover, the evolution of the copper incorporation during the PMO synthesis has been followed by EPR. The results show that the immobilization of the Cu2+ ion/complex and the formation of the PMO materials are taking place simultaneously. The copper ions are found to be situated on the inner surface of the mesopores of the materials and are accessible, which will be beneficial for the catalytic applications. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000355000700028 |
Publication Date |
2015-04-28 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1477-9226;1477-9234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
11 |
Open Access |
OpenAccess |
Notes |
Goa-Bof; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 4.029; 2015 IF: 4.197 |
Call Number |
c:irua:126422 |
Serial |
725 |
Permanent link to this record |
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Author |
Tyablikov, O.A.; Batuk, D.; Tsirlin, A.A.; Batuk, M.; Verchenko, V.Y.; Filimonov, D.S.; Pokholok, K.V.; Sheptyakov, D.V.; Rozova, M.G.; Hadermann, J.; Antipov, E.V.; Abakumov, A.M.; |
Title |
{110}-Layered B-cation ordering in the anion-deficient perovskite Pb2.4Ba2.6Fe2Sc2TiO13 with the crystallographic shear structure |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
44 |
Issue |
44 |
Pages |
10753-10762 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A novel anion-deficient perovskite-based compound, Pb2.4Ba2.6Fe2Sc2TiO13, was synthesized via the citrate-based route. This compound is an n = 5 member of the A(n)B(n)O(3n-2) homologous series with unit-cell parameters related to the perovskite subcell a(p) approximate to 4.0 angstrom as a(p)root 2 x a(p) x 5a(p)root 2. The crystal structure of Pb2.4Ba2.6Fe2Sc2TiO13 consists of quasi-2D perovskite blocks with a thickness of three octahedral layers separated by the 1/2[110]((1) over bar 01)(p) crystallographic shear (CS) planes, which are parallel to the {110} plane of the perovskite subcell. The CS planes transform the corner-sharing octahedra into chains of edge-sharing distorted tetragonal pyramids. Using a combination of neutron powder diffraction, Fe-57 Mossbauer spectroscopy and atomic resolution electron energy-loss spectroscopy we demonstrate that the B-cations in Pb2.4Ba2.6Fe2Sc2TiO13 are ordered along the {110} perovskite layers with Fe3+ in distorted tetragonal pyramids along the CS planes, Ti4+ preferentially in the central octahedra of the perovskite blocks and Sc3+ in the outer octahedra of the perovskite blocks. Magnetic susceptibility and Mossbauer spectroscopy indicate a broadened magnetic transition around T-N similar to 45 K and the onset of local magnetic fields at low temperatures. The magnetic order is probably reminiscent of that in other A(n)B(n)O(3n-2) homologues, where G-type AFM order within the perovskite blocks has been observed. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000355701000026 |
Publication Date |
2015-01-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1477-9226;1477-9234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.029; 2015 IF: 4.197 |
Call Number |
c:irua:127001 |
Serial |
22 |
Permanent link to this record |
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Author |
De Schouwer, F.; Claes, L.; Claes, N.; Bals, S.; Degrève, J.; De Vos, D.E. |
Title |
Pd-catalyzed decarboxylation of glutamic acid and pyroglutamic acid to bio-based 2-pyrrolidone |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Green chemistry : cutting-edge research for a greener sustainable future |
Abbreviated Journal |
Green Chem |
Volume |
17 |
Issue |
17 |
Pages |
2263-2270 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In order to recycle nitrogen from nitrogen-rich waste streams, particularly protein waste, we studied the decarboxylation of pyroglutamic acid and glutamic acid in a one-pot reaction to bio-based 2-pyrrolidone. After the screening of a wide range of supported Pd and Pt catalysts, 5 wt% Pd/Al2O3 displayed the highest yield (70%) and selectivity (81%) for the decarboxylation of pyroglutamic acid in water at 250 °C and under an inert atmosphere. Side products originate from consecutive reactions of 2-pyrrolidone; different reaction pathways are proposed to explain the presence of degradation products like propionic acid, γ-hydroxybutyric acid, γ-butyrolactone and methylamine. An extensive study of the reaction parameters was performed to check their influence on selectivity and conversion. This heterogeneous catalytic system was successfully extended to the conversion of glutamic acid. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000352724200027 |
Publication Date |
2015-02-17 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9262;1463-9270; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.125 |
Times cited |
47 |
Open Access |
OpenAccess |
Notes |
335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 9.125; 2015 IF: 8.020 |
Call Number |
c:irua:125378 |
Serial |
2564 |
Permanent link to this record |
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|
Author |
Radepont, M.; Coquinot, Y.; Janssens, K.; Ezrati, J.-J.; de Nolf, W.; Cotte, M. |
Title |
Thermodynamic and experimental study of the degradation of the red pigment mercury sulfide |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
30 |
Issue |
3 |
Pages |
599-612 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The red pigment mercury sulfide, called cinnabar or vermilion, is well known to suffer from an alteration giving rise to a grey, grey-white or black color at the surface of degraded works of art. This phenomenon can dramatically affect the esthetical value of artworks. This work aims at assessing the factors (light, halides) influencing the instability of red mercury sulfide and understanding (by combining thermodynamic and experimental approaches) the chemical equilibria governing the formation and evolution of the different degradation compounds. From the thermodynamic study of the Hg-S-Cl-H2O system, it was concluded that Hg(0), Hg3S2Cl2, and Hg2Cl2 can be formed from the reaction of alpha-HgS with ClO(g). In the second part, the artificial ageing experiments presented were carried out on model samples following the conditions assessed in the first part, in order to reproduce natural ageing observed on red mercury sulfide. Similarly to degradation compounds detected on original works of art, mercury chlorine compounds such as calomel (Hg2Cl2) and corderoite (alpha-Hg3S2Cl2) were identified on the surface of alpha-HgS model samples, when exposed to light and a sodium hypochlorite solution. Sulfates were detected as well, and more particularly gypsum (CaSO4 center dot 2H(2)O) when Ca was originally present in the model sample. The relationship between color and composition is discussed as well. |
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 |
000350650800005 |
Publication Date |
2015-01-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
26 |
Open Access |
|
Notes |
; The authors gratefully acknowledge the ESRF for granting beamtime under proposal no. EC720. Michel Dubus is thanked for providing precious advices concerning ageing protocols. This research was supported by Belgian Science Policy project S2-ART (BELSPO S4DA), the GOA “SOLARPAINT” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0C12.13, G.0704.08 and G.01769.09. ; |
Approved |
Most recent IF: 3.379; 2015 IF: 3.466 |
Call Number |
UA @ admin @ c:irua:125474 |
Serial |
5877 |
Permanent link to this record |
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Author |
Nuyts, G.; Cagno, S.; Bugani, S.; Janssens, K. |
Title |
Micro-XANES study on Mn browning: use of quantitative valence state maps |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
30 |
Issue |
3 |
Pages |
642-650 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Historical glass, especially non-durable medieval glass, can undergo corrosion. This sometimes results in the formation of dark-coloured manganese-rich inclusions that reduce the transparency of the glass. While unaltered bulk glass contains manganese mainly present in the +II valence state, inside the inclusions Mn is present in higher valence states (+III to +IV). Two different strategies may be considered by conservators when aiming to improve the transparency. One is based on the reduction of highly oxidised black/brown compounds using mildly reducing solutions, while the other focuses more on the extraction of manganese from the inclusions by the application of chelating agents. In this paper, a method for quantitative mapping of the Mn speciation inside partially corroded historical windowpanes based on X-Ray Absorption Near-Edge Structure (XANES) spectroscopy is discussed. The calibration of such Mn valence state maps based on the combo method, a fairly reliable way to determine the oxidation state, is described in more detail. This method is used to evaluate the effect of reducing treatments on historical glass, dated to the 14th century and originating from Sidney Sussex College (Cambridge, UK), suffering from Mn browning. Glasses were examined by means of Synchrotron Radiation (SR) based microscopic X-Ray Absorption Near-Edge Structure (mXANES) spectroscopy and microscopic X-Ray Fluorescence (mXRF). X-Ray elemental distribution maps of glass cross-sections are recorded at different energies, while Mn K-edge spectra are used to convert these into Mn valence state (VS) maps. Such valence state maps will allow evaluation of a reducing treatment. |
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 |
000350650800009 |
Publication Date |
2015-02-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
8 |
Open Access |
|
Notes |
; This research was supported by the Interuniversity Attraction Poles Programme Belgian Science Policy (IUAP VI/16) and partially by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. The text also presents results of Center of Excellence AGRECHEM (Research Fund University of Antwerp, Belgium) and from the Fund for Scientific Research (FWO, Brussels, Belgium) projects no. G.0C12.13 and G.01769.09. We gratefully acknowledge ESRF for granting beamtime (experiment EC768) and the beamline scientists of ID21 for their support. The authors also want to thank Leonie Seliger of Canterbury Cathedral, UK, the Sidney Sussex College Council and Bursar Charles Larkum for providing the archaeological samples of the Franciscan Friary which are kept in store for Sidney Sussex College in Cambridge (UK). ; |
Approved |
Most recent IF: 3.379; 2015 IF: 3.466 |
Call Number |
UA @ admin @ c:irua:125476 |
Serial |
5719 |
Permanent link to this record |
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|
Author |
Alfeld, M.; Janssens, K. |
Title |
Strategies for processing mega-pixel X-ray fluorescence hyperspectral data: a case study on a version of Caravaggio's painting Supper at Emmaus |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
30 |
Issue |
3 |
Pages |
777-789 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Technical progress in the fields of X-ray sources, optics and detectors is constantly enhancing the pace of data acquisition in XRF imaging. This enlarges the size of the hyperspectral datasets and the number of their sub-parts. This paper describes the challenges in processing large XRF datasets featuring several million pixels/spectra and the strategies developed to overcome them. During the investigation of historical paintings by scanning macro-XRF the main challenges are the correct identification of all spectral features in a dataset and its timely processing. For the identification of spectral features different approaches are discussed, i.e. the use of sum spectra, maximum pixel spectra and of chi(2)(r) maps. For the time-efficient, artefact-free evaluation of XRF imaging data, different software packages are evaluated and intercompared (AXIL, PyMCA, GeoPIXE and the in-house written datamuncher). The process of data evaluation is illustrated on a large dataset (3.4 MPixels) acquired during the investigation of a version of Caravaggio's Supper at Emmaus (143 x 199.5 cm(2)). This 17th century painting is currently the largest object entirely scanned with macroscopic XRF. |
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 |
000350650800026 |
Publication Date |
2015-02-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
67 |
Open Access |
|
Notes |
; The authors would like to thank W. de Nolf, A. Rothkirch, C. Ryan, A. Sole, B. Vekemans, P. van Espen and L. Vincze for their fruitful discussions over the years. Furthermore, the authors thank D. Swetzoff for his support. M. Alfeld was from 2009 to 2013 the recipient of a Ph.D. fellowship of the Research Foundation-Flanders (FWO, Brussels). ; |
Approved |
Most recent IF: 3.379; 2015 IF: 3.466 |
Call Number |
UA @ admin @ c:irua:125477 |
Serial |
5848 |
Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Alfeld, M.; Cotte, M.; Vanmeert, F.; Ryan, C.G.; Falkenberg, G.; Howard, D.L.; Brunetti, B.G.; Miliani, C. |
Title |
Full spectral XANES imaging using the Maia detector array as a new tool for the study of the alteration process of chrome yellow pigments in paintings by Vincent van Gogh |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
30 |
Issue |
3 |
Pages |
613-626 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A combination of synchrotron radiation (SR) micro X-ray fluorescence (m-XRF) and XRF mode X-ray absorption near edge structure (XANES) measurements at the Cr K-edge already allowed us to establish that the photo-reduction of chromates to Cr(III) compounds is the cause of darkening of chrome yellow pigments (PbCr1-xSxO4, 0 <= x <= 0.8) in a number of paintings by Vincent van Gogh and in corresponding artificially aged paint models. A silicon drift detector (SDD) was employed to record the Cr-K XRF radiation in these X-ray micro beam-based measurements. However, in view of the limited count rate capabilities and collection solid angle of a single device, m-XRF and m-XANES employing single element SDDs (or similar) are primarily suited for collection of spectral data from individual points. Additionally, collection of XRF maps via point-by-point scanning with relatively long dwell times per point is possible but is usually confined to small areas. The development of the 384 silicon-diode array Maia XRF detector has provided valuable solutions in terms of data acquisition rate, allowing for full spectral (FS) XANES imaging in XRF mode, i.e., where spectroscopic information is available at each pixel in the scanned map. In this paper, the possibilities of SR Cr K-edge FS-XANES imaging in XRF mode using the Maia detector are examined as a new data collection strategy to study the speciation and distribution of alteration products of lead chromate-based pigments in painting materials. The results collected from two micro-samples taken from two Van Gogh paintings and an aged paint model show the possibility to perform FS-XANES imaging in practical time frames (from several minutes to a few hours) by scanning regions of sample sizes of the same order (more than 500 mm). The sensitivity and capabilities of FS-XANES imaging in providing representative chemical speciation information at the microscale (spatial resolution from similar to 2 to 0.6 mm) over the entire scanned area are demonstrated by the identification of Cr(OH) 3, Cr(III) sulfates and/or Cr(III) organometallic compounds in the corresponding phase maps, as alteration products. Comparable Cr-speciation results were obtained by performing equivalent higher spatial resolution SR m-XRF/single-point m-XANES analysis using a more conventional SDD from smaller regions of interest of each sample. Thus, large-area XRF mode FS-XANES imaging (Maia detector) is here proposed as a valuable and complementary data collection strategy in relation to “ zoomed-in” high-resolution m-XRF mapping and single-point m-XANES analysis (SDD). |
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 |
000350650800006 |
Publication Date |
2014-12-17 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
28 |
Open Access |
|
Notes |
; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (S2-ART project S4DA), GOA “SOLARPAINT” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) project no. G.0C12.13, G.0704.08 and G.01769.09. Support from the Italian projects PRIN (SICH Sustainability in Cultural Heritage: from diagnosis to the development of innovative system for consolidation, cleaning and protection) and PON (ITACHA Italian advanced technologies for cultural heritage applications) is also acknowledged. For the grants received thanks are expressed to ESRF (experiments EC-799, EC-1051) and DESY (experiment H-20000043). Part of this research was undertaken at the XFM beamline at the Australian Synchrotron, Victoria, Australia (experiment M4604). LM acknowledges the CNR for the financial support received in the framework of the Short Term Mobility Programme 2013. Thanks are expressed to Ella Hendriks (Van Gogh Museum, Amsterdam), Muriel Geldof (Cultural Heritage Agency of The Netherlands) and Margje Leeuwestein (Kroller-Muller Museum, Otterlo) for selecting and sharing the information on the cross-section taken from the paintings The Bedroom and Falling Leaves (Les Alyscamps). All the staff of the Van Gogh Museum and the Kroller-Muller Museum are acknowledged for their agreeable cooperation. ; |
Approved |
Most recent IF: 3.379; 2015 IF: 3.466 |
Call Number |
UA @ admin @ c:irua:125475 |
Serial |
5628 |
Permanent link to this record |
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Author |
Mourdikoudis, S.; Chirea, M.; Zanaga, D.; Altantzis, T.; Mitrakas, M.; Bals, S.; Marzán, L.M.; Pérez-Juste, J.; Pastoriza-Santos, I. |
Title |
Governing the morphology of PtAu heteronanocrystals with improved electrocatalytic performance |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
7 |
Issue |
7 |
Pages |
8739-8747 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Platinumgold heteronanostructures comprising either dimer (PtAu) or coresatellite (Pt@Au) configurations were synthesized by means of a seeded growth procedure using platinum nanodendrites as seeds. Careful control of the reduction kinetics of the gold precursor can be used to direct the nucleation and growth of gold nanoparticles on either one or multiple surface sites simultaneously, leading to the formation of either dimers or coresatellite nanoparticles, respectively, in high yields. Characterization by electron tomography and high resolution electron microscopy provided a better understanding of the actual three-dimensional particle morphology, as well as the AuPt interface, revealing quasi-epitaxial growth of Au on Pt. The prepared PtAu bimetallic nanostructures are highly efficient catalysts for ethanol oxidation in alkaline solution, showing accurate selectivity, high sensitivity, and improved efficiency by generating higher current densities than their monometallic counterparts. |
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 |
|
Language |
|
Wos |
000354204400011 |
Publication Date |
2015-03-12 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
41 |
Open Access |
OpenAccess |
Notes |
335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 7.367; 2015 IF: 7.394 |
Call Number |
c:irua:126354 |
Serial |
1360 |
Permanent link to this record |
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|
|
Author |
Lin, F.; Meng; Kukueva, E.; Mertens, M.; Van Doorslaer, S.; Bals, S.; Cool, P. |
Title |
New insights into the mesophase transformation of ethane-bridged PMOs by the influence of different counterions under basic conditions |
Type |
A1 Journal article |
Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
Volume |
5 |
Issue |
5 |
Pages |
5553-5562 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
The counterions are of crucial importance in determining the mesostructure and morphology of ethanebridged PMO materials synthesized under basic conditions. By using CTABr as the surfactant, the final PMO materials show a 2-D hexagonal (p6mm) mesophase, while PMO materials with cubic (Pm (3) over barn ) mesostructure are obtained when CTACl or CTA(SO4)(1)/(2) are used. With gradually replacing CTABr by CTACl or CTA(SO4) (1)/(2) while keeping the total surfactant concentration constant, a clear p6mm to Pm (3) over barn 3n mesophase evolution process is observed. For a given gel composition, the mesophase of ethanebridged PMO materials can also be adjusted by the addition of different sodium salts. In short, the effect of the counterions on the mesophase can be attributed to the binding strength of the ions on the surfactant micelles, which follows the Hofmeister series (SO42- < Cl- < Br-< NO3- < SCN-). Furthermore, it is found that the hydrolysis and condensation rate of the organosilica precursor also plays an important role in the formation of the final mesostructure |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000347304900010 |
Publication Date |
2014-12-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2046-2069; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.108 |
Times cited |
6 |
Open Access |
Not_Open_Access |
Notes |
; The Erasmus Mundus CONNEC program is acknowledged for PhD funding of F. L. Furthermore, the authors acknowledge support by the GOA-BOF project 'Optimization of the structureactivity relation in nanoporous materials', funded by the University of Antwerp. ; |
Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
Call Number |
c:irua:123768 |
Serial |
2317 |
Permanent link to this record |
|
|
|
Author |
Lieberman, C.M.; Filatov, A.S.; Wei, Z.; Rogachev, A.Y.; Abakumov, A.M.; Dikarev, E.V. |
Title |
Mixed-valent, heteroleptic homometallic diketonates as templates for the design of volatile heterometallic precursors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
Volume |
6 |
Issue |
6 |
Pages |
2835-2842 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A novel series of mixed-valent, heteroleptic transition metal diketonates that can be utilized as prospective single-source precursors for the low-temperature preparation of oxide materials are reported. The first mixed-valent iron beta-diketonates with different Fe-III/Fe-II ratios have been synthesized by applying the mixed-ligand approach. Based on nearly quantitative reaction yields and analysis of iron-oxygen bonds, these compounds were formulated as [Fe-III(acac)(3)][Fe-II(hfac)(2)] (1) and [Fe-II(hfac)(2)][Fe-III(acac)(3)][Fe-II(hfac)(2)] (2). In the above heteroleptic complexes, the Lewis acidic, coordinatively unsaturated Fe-II centers chelated by two hfac (hexafluoroacetylacetonate) ligands with electron-withdrawing substituents maintain bridging interactions with oxygen atoms of electron-donating acac (acetylacetonate) groups that chelate the neighboring Fe-III atoms. Switching the ligands on Fe-III and Fe-II atoms in starting reagents resulted in the instant ligand exchange between iron centers and in yet another polynuclear homometallic diketonate [Fe-II(hfac)(2)][Fe-III(acac)(2)(hfac)][Fe-II(hfac)(2)] (3) that adheres to the same bonding pattern as in complexes 1 and 2. The proposed synthetic methodology has been extended to design heterometallic diketonates with different M : M' ratios. Homometallic parent molecules have been used as templates to obtain heterometallic mixed-valent [Fe-III(acac)(3)][Mn-II(hfac)(2)] (4) and [Ni-II(hfac)(2)] – [Fe-III(acac)(3)][Ni-II(hfac)(2)] (5) complexes. The combination of two different diketonate ligands with electron-donating and electron-withdrawing substituents was found to be crucial for maintaining the above mixed-valent heterometallic assemblies. Theoretical investigation of two possible “isomers”, [Fe-III(acac)(3)][Mn-II(hfac)(2)] (4) and [Mn-III(acac)(3)][Fe-II(hfac)(2)] (40) provided an additional support for the metal site assignment giving a preference of 9.78 kcal mol(-1) for the molecule 4. Heterometallic complexes obtained in the course of this study have been found to act as effective single-source precursors for the synthesis of mixed-transition metal oxide materials MxM2-xO3 and MxMi-xO. The title highly volatile precursors can be used for the low-temperature preparation of both amorphous and crystalline heterometallic oxides in the form of thin films or nanosized particles that are known to operate as efficient catalysts in oxygen evolution reaction. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Royal Society of Chemistry |
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000353223100021 |
Publication Date |
2015-02-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-6520;2041-6539; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.668 |
Times cited |
13 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.668; 2015 IF: 9.211 |
Call Number |
c:irua:126031 |
Serial |
2092 |
Permanent link to this record |
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|
|
Author |
Deng, S.; Kurttepeli, M.; Cott, D.J.; Bals, S.; Detavernier, C. |
Title |
Porous nanostructured metal oxides synthesized through atomic layer deposition on a carbonaceous template followed by calcination |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
Volume |
3 |
Issue |
3 |
Pages |
2642-2649 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Porous metal oxides with nano-sized features attracted intensive interest in recent decades due to their high surface area which is essential for many applications, e.g. Li ion batteries, photocatalysts, fuel cells and dye-sensitized solar cells. Various approaches have so far been investigated to synthesize porous nanostructured metal oxides, including self-assembly and template-assisted synthesis. For the latter approach, forests of carbon nanotubes are considered as particularly promising templates, with respect to their one-dimensional nature and the resulting high surface area. In this work, we systematically investigate the formation of porous metal oxides (Al2O3, TiO2, V2O5 and ZnO) with different morphologies using atomic layer deposition on multi-walled carbon nanotubes followed by post-deposition calcination. X-ray diffraction, scanning electron microscopy accompanied by X-ray energy dispersive spectroscopy and transmission electron microscopy were used for the investigation of morphological and structural transitions at the micro- and nano-scale during the calcination process. The crystallization temperature and the surface coverage of the metal oxides and the oxidation temperature of the carbon nanotubes were found to produce significant influence on the final morphology. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000348990500019 |
Publication Date |
2014-12-06 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2050-7488;2050-7496; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.867 |
Times cited |
23 |
Open Access |
OpenAccess |
Notes |
Fwo; 239865 Cocoon; 335078 Colouratoms; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 8.867; 2015 IF: 7.443 |
Call Number |
c:irua:125298 |
Serial |
2673 |
Permanent link to this record |
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|
|
Author |
Çakir, D.; Peeters, F.M. |
Title |
Fluorographane : a promising material for bipolar doping of MoS2 |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
17 |
Issue |
17 |
Pages |
27636-27641 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using first principles calculations we investigate the structural and electronic properties of interfaces between fluorographane and MoS2. Unsymmetrical functionalization of graphene with H and F results in an intrinsic dipole moment perpendicular to the plane of the buckled graphene skeleton. Depending on the orientation of this dipole moment, the electronic properties of a physically absorbed MoS2 monolayer can be switched from n-to p-type or vice versa. We show that one can realize vanishing n-type/p-type Schottky barrier heights when contacting MoS2 to fluorographane. By applying a perpendicular electric field, the size of the Schottky barrier and the degree of doping can be tuned. Our calculations indicate that a fluorographane monolayer is a promising candidate for bipolar doping of MoS2, which is vital in the design of novel technological applications based on two-dimensional materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000363193800043 |
Publication Date |
2015-09-25 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
7 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. ; |
Approved |
Most recent IF: 4.123; 2015 IF: 4.493 |
Call Number |
UA @ lucian @ c:irua:129477 |
Serial |
4182 |
Permanent link to this record |
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Author |
Kang, J.; Sahin, H.; Peeters, F.M. |
Title |
Mechanical properties of monolayer sulphides : a comparative study between MoS2, HfS2 and TiS3 |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
17 |
Issue |
17 |
Pages |
27742-27749 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The in-plane stiffness (C), Poisson's ratio (nu), Young's modulus and ultimate strength (sigma) along two different crystallographic orientations are calculated for the single layer crystals: MoS2, HfS2 and TiS3 in 1H, 1T and monoclinic phases. We find that MoS2 and HfS2 have isotropic in-plane stiffnesses of 124.24 N m(-1) and 79.86 N m(-1), respectively. While for TiS3 the in-plane stiffness is highly anisotropic due to its monoclinic structure, with C-x = 83.33 N m(-1) and C-y = 133.56 N m(-1) (x and y are parallel to its longer and shorter in-plane lattice vectors.). HfS2 which is in the 1T phase has the smallest anisotropy in its ultimate strength, whereas TiS3 in the monoclinic phase has the largest. Along the armchair direction MoS2 has the largest sigma of 23.48 GPa, whereas along y TiS3 has the largest sigma of 18.32 GPa. We have further analyzed the band gap response of these materials under uniaxial tensile strain, and find that they exhibit different behavior. Along both armchair and zigzag directions, the band gap of MoS2 (HfS2) decreases (increases) as strain increases, and the response is almost isotropic. For TiS3, the band gap decreases when strain is along x, while if strain is along y, the band gap increases first and then decreases beyond a threshold strain value. The different characteristics observed in these sulphides with different structures shed light on the relationship between the structure and properties, which is useful for applications in nanotechnology. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000363193800055 |
Publication Date |
2015-09-25 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
83 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Super-computer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. ; |
Approved |
Most recent IF: 4.123; 2015 IF: 4.493 |
Call Number |
UA @ lucian @ c:irua:129478 |
Serial |
4204 |
Permanent link to this record |
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Author |
Bogaerts, A.; Kozak, T.; van Laer, K.; Snoeckx, R. |
Title |
Plasma-based conversion of CO2: current status and future challenges |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Faraday discussions |
Abbreviated Journal |
Faraday Discuss |
Volume |
183 |
Issue |
183 |
Pages |
217-232 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
This paper discusses our recent results on plasma-based CO2 conversion, obtained by a combination of experiments and modeling, for a dielectric barrier discharge (DBD), a microwave plasma and a packed bed DBD reactor. The results illustrate that plasma technology is quite promising for CO2 conversion, but more research is needed to better understand the underlying mechanisms and to further improve the capabilities. |
Address |
Research Group PLASMANT, University of Antwerp, Department of Chemistry, Universiteitsplein 1, Antwerp, Belgium. annemie.bogaerts@uantwerpen.be |
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 |
000365914900013 |
Publication Date |
2015-06-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1359-6640 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.588 |
Times cited |
89 |
Open Access |
|
Notes |
We thank R. Aerts and W. van Gaens for setting up the experimental systems and for the interesting results obtained during their PhD study in our group. We also acknowledge nancial support from the IAP/7 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’ by the Belgian Federal Office for Science Policy (BELSPO), the Fund for Scientic Research Flanders (FWO) and the EU-FP7-ITN network “RAPID”. |
Approved |
Most recent IF: 3.588; 2015 IF: 4.606 |
Call Number |
c:irua:130318 |
Serial |
3983 |
Permanent link to this record |
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Author |
La Porta, A.; Sanchez-Iglesias, A.; Altantzis, T.; Bals, S.; Grzelczak, M.; Liz-Marzan, L.M. |
Title |
Multifunctional self-assembled composite colloids and their application to SERS detection |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
7 |
Issue |
7 |
Pages |
10377-10381 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
We present a simple method for the co-encapsulation of gold nanostars and iron-oxide nanoparticles into hybrid colloidal composites that are highly responsive to both light and external magnetic fields. Self-assembly was driven by hydrophobic interactions between polystyrene capped gold nanostars and iron oxide nanocrystals stabilized with oleic acid, upon addition of water. A block copolymer was then used to encapsulate the resulting spherical colloidal particle clusters, which thereby became hydrophilic. Electron microscopy analysis unequivocally shows that each composite particle comprises a single Au nanostar surrounded by a few hundreds of iron oxide nanocrystals. We demonstrate that this hybrid colloidal system can be used as an efficient substrate for surface enhanced Raman scattering, using common dyes as model molecular probes. The co-encapsulation of iron oxide nanoparticles renders the system magnetically responsive, so that application of an external magnetic field leads to particle accumulation and limits of detection are in the nM range. |
Address |
A1 Article; Electron microscopy for materials research (EMAT); |
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 |
000355987300010 |
Publication Date |
2015-04-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
51 |
Open Access |
OpenAccess |
Notes |
267867 Plasmaquo; 335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 7.367; 2015 IF: 7.394 |
Call Number |
c:irua:127003 |
Serial |
3940 |
Permanent link to this record |
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Author |
Egoavil, R.; Huehn, S.; Jungbauer, M.; Gauquelin, N.; Béché, A.; Van Tendeloo, G.; Verbeeck; Moshnyaga, V. |
Title |
Phase problem in the B-site ordering of La2CoMnO6 : impact on structure and magnetism |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
7 |
Issue |
7 |
Pages |
9835-9843 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Epitaxial double perovskite La2CoMnO6 (LCMO) films were grown by metalorganic aerosol deposition on SrTiO3(111) substrates. A high Curie temperature, T-C = 226 K, and large magnetization close to saturation, M-S(5 K) = 5.8 mu(B)/f.u., indicate a 97% degree of B-site (Co,Mn) ordering within the film. The Co/Mn ordering was directly imaged at the atomic scale by scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDX). Local electron-energy-loss spectroscopy (EELS) measurements reveal that the B-sites are predominantly occupied by Co2+ and Mn4+ ions in quantitative agreement with magnetic data. Relatively small values of the (1/2 1/2 1/2) superstructure peak intensity, obtained by X-ray diffraction (XRD), point out the existence of ordered domains with an arbitrary phase relationship across the domain boundary. The size of these domains is estimated to be in the range 35-170 nm according to TEM observations and modelling the magnetization data. These observations provide important information towards the complexity of the cation ordering phenomenon and its implications on magnetism in double perovskites, and similar materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000354983100060 |
Publication Date |
2015-05-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
37 |
Open Access |
|
Notes |
312483 ESTEEM2; FWO G004413N; 246102 IFOX; Hercules; esteem2_jra3 |
Approved |
Most recent IF: 7.367; 2015 IF: 7.394 |
Call Number |
c:irua:126423 c:irua:126423 |
Serial |
2586 |
Permanent link to this record |
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Author |
Snoeckx, R.; Zeng, Y.X.; Tu, X.; Bogaerts, A. |
Title |
Plasma-based dry reforming : improving the conversion and energy efficiency in a dielectric barrier discharge |
Type |
A1 Journal article |
Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
Volume |
5 |
Issue |
5 |
Pages |
29799-29808 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Dry reforming of methane has gained significant interest over the years. A novel reforming technique with great potential is plasma technology. One of its drawbacks, however, is energy consumption. Therefore, we performed an extensive computational study, supported by experiments, aiming to identify the influence of the operating parameters (gas mixture, power, residence time and frequency) of a dielectric barrier discharge plasma on the conversion and energy efficiency, and to investigate which of these parameters lead to the most promising results and whether these are eventually sufficient for industrial implementation. The best results, in terms of both energy efficiency and conversion, are obtained at a specific energy input (SEI) of 100 J cm−3, a 1090 CH4CO2 ratio, 10 Hz, a residence time of 1 ms, resulting in a total conversion of 84% and an energy efficiency of 8.5%. In general, increasing the CO2 content in the gas mixture leads to a higher conversion and energy efficiency. The SEI couples the effect of the power and residence time, and increasing the SEI always results in a higher conversion, but somewhat lower energy efficiencies. The effect of the frequency is more complicated: we observed that the product of frequency (f) and residence time (τ), being a measure for the total number of micro-discharge filaments which the gas molecules experience when passing through the reactor, was critical. For most cases, a higher number of filaments yields higher values for conversion and energy efficiency. To benchmark our model predictions, we also give an overview of measured conversions and energy efficiencies reported in the literature, to indicate the potential for improvement compared to the state-of-the art. Finally, we identify the limitations as well as the benefits and future possibilities of plasma technology. |
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 |
000352789500026 |
Publication Date |
2015-03-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2046-2069; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.108 |
Times cited |
67 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
Call Number |
c:irua:132577 |
Serial |
2629 |
Permanent link to this record |
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Author |
Zalfani, M.; van der Schueren, B.; Hu, Z.-Y.; Rooke, J.C.; Bourguiga, R.; Wu, M.; Li, Y.; Van Tendeloo, G.; Su, B.-L. |
Title |
Novel 3DOM BiVO4/TiO2nanocomposites for highly enhanced photocatalytic activity |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
Volume |
3 |
Issue |
3 |
Pages |
21244-21256 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Novel 3DOM BiVO4/TiO2 nanocomposites with intimate contact were for the first time synthesized by a hydrothermal method in order to elucidate their visible-light-driven photocatalytic performances. BiVO4 nanoparticles and 3DOM TiO2 inverse opal were fabricated respectively. These materials were characterized by XRD, XPS, SEM, TEM, N2 adsorption–desorption and UV-vis diffuse (UV-vis) and photoluminescence spectroscopies. As references for comparison, a physical mixture of BiVO4 nanoparticles and 3DOM TiO2 inverse opal powder (0.08 : 1), and a BiVO4/P25 TiO2 (0.08 : 1) nanocomposite made also by the hydrothermal method were prepared. The photocatalytic performance of all the prepared materials was evaluated by the degradation of rhodamine B (RhB) as a model pollutant molecule under visible light irradiation. The highly ordered 3D macroporous inverse opal structure can provide more active surface areas and increased mass transfer because of its highly accessible 3D porosity. The results show that 3DOM BiVO4/TiO2 nanocomposites possess a highly prolonged lifetime and increased separation of visible light generated charges and extraordinarily high photocatalytic activity. Owing to the intimate contact between BiVO4 and large surface area 3DOM TiO2, the photogenerated high energy charges can be easily transferred from BiVO4 to the 3DOM TiO2 support. BiVO4 nanoparticles in the 3DOM TiO2 inverse opal structure act thus as a sensitizer to absorb visible light and to transfer efficiently high energy electrons to TiO2 to ensure long lifetime of the photogenerated charges and keep them well separated, owing to the direct band gap of BiVO4 of 2.4 eV, favourably positioned band edges, very low recombination rate of electron–hole pairs and stability when coupled with photocatalysts, explaining the extraordinarily high photocatalytic performance of 3DOM BiVO4/TiO2 nanocomposites. It is found that larger the amount of BiVO4 in the nanocomposite, longer the duration of photogenerated charge separation and higher the photocatalytic activity. This work can shed light on the development of novel visible light responsive nanomaterials for efficient solar energy utilisation by the intimate combination of an inorganic light sensitizing nanoparticle with an inverse opal structure with high diffusion efficiency and high accessible surface area. |
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 |
000363163200049 |
Publication Date |
2015-09-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2050-7488;2050-7496; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.867 |
Times cited |
88 |
Open Access |
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Notes |
This work was realized with the financial support of the Belgian FNRS (Fonds National de la Recherche Scientifique). This research used resources of the Electron Microscopy Service located at the University of Namur. This Service is a member of the “Plateforme Technologique Morphologie – Imagerie”. The XPS analyses were made in the LISE, Department of Physics of the University of Namur thanks to Dr P. Louette. This work was also supported by Changjiang Scholars and the Innovative Research Team (IRT1169) of the Ministry of Education of the People's Republic of China. B. L. Su acknowledges the Chinese Central Government for an “Expert of the State” position in the Program of the “Thousand Talents” and a Clare Hall Life Membership at the Clare Hall and the financial support of the Department of Chemistry, University of Cambridge. G. Van Tendeloo and Z. Y. Hu acknowledge support from the EC Framework 7 program ESTEEM2 (Reference 312483).; esteem2_jra4 |
Approved |
Most recent IF: 8.867; 2015 IF: 7.443 |
Call Number |
c:irua:129476 c:irua:129476 |
Serial |
3951 |
Permanent link to this record |
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Author |
Wee, L.H.; Meledina, M.; Turner, S.; Custers, K.; Kerkhofs, S.; Van Tendeloo, G.; Martens, J.A. |
Title |
Hematite iron oxide nanorod patterning inside COK-12 mesochannels as an efficient visible light photocatalyst |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
Volume |
3 |
Issue |
3 |
Pages |
19884-19891 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The uniform dispersion of functional oxide nanoparticles on the walls of ordered mesoporous silica to tailor optical, electronic, and magnetic properties for biomedical and environmental applications is a scientific challenge. Here, we demonstrate homogeneous confined growth of 5 nanometer-sized hematite iron oxide (α-Fe2O3) inside mesochannels of ordered mesoporous COK-12 nanoplates. The three-dimensional inclusion of the α-Fe2O3 nanorods in COK-12 particles is studied using high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), energy-dispersive X-ray (EDX) spectroscopy and electron tomography. High resolution imaging and EDX spectroscopy provide information about the particle size, shape and crystal phase of the loaded α-Fe2O3 material, while electron tomography provides detailed information on the spreading of the nanorods throughout the COK-12 host. This nanocomposite material, having a semiconductor band gap energy of 2.40 eV according to diffuse reflectance spectroscopy, demonstrates an improved visible light photocatalytic degradation activity with rhodamine 6G and 1-adamantanol model compounds. |
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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 |
000362041300033 |
Publication Date |
2015-08-26 |
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 |
2050-7488;2050-7496; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.867 |
Times cited |
9 |
Open Access |
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Notes |
L.H.W. and S.T. thank the FWO-Vlaanderen for a postdoctoral research fellowship (12M1415N) and under contract number G004613N . J.A.M gratefully acknowledge financial supports from Flemish Government (Long-term structural funding-Methusalem). Collaboration among universities was supported by the Belgian Government (IAP-PAI network). |
Approved |
Most recent IF: 8.867; 2015 IF: 7.443 |
Call Number |
c:irua:132567 |
Serial |
3959 |
Permanent link to this record |