| |
Records |
Links |
|
Author |
Yu, W.-B.; Hu, Z.-Y.; Yi, M.; Huang, S.-Z.; Chen, D.-S.; Jin, J.; Li, Y.; Van Tendeloo, G.; Su, B.-L. |
|
| |
Title |
Probing the electrochemical behavior of {111} and {110} faceted hollow Cu2O microspheres for lithium storage |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
6 |
Issue |
6 |
Pages |
97129-97136 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Transition metal oxides with exposed highly active facets have become of increasing interest as anode materials for lithium ion batteries, because more dangling atoms exposed at the active surface facilitate the reaction between the transition metal oxides and lithium. In this work, we probed the electrochemical behavior of hollow Cu2O microspheres with {111} and {110} active facets on the polyhedron surface as anodes for lithium storage. Compared to commercial Cu2O nanoparticles, hollow Cu2O microspheres with {111} and {110} active facets show a rising specific capacity at 30 cycles which then decreases after 110 cycles during the cycling process. Via advanced electron microscopy characterization, we reveal that this phenomenon can be attributed to the highly active {111} and {110} facets with dangling “Cu” atoms facilitating the conversion reaction of Cu2O and Li, where part of the Cu2O is oxidized to CuO during the charging process. However, as the reaction proceeds, more and more formed Cu nanoparticles cannot be converted to Cu2O or CuO. This leads to a decrease of the specific capacity. We believe that our study here sheds some light on the progress of the electrochemical behavior of transition metal oxides with respect to their increased specific capacity and the subsequent decrease via a conversion reaction mechanism. These results will be helpful to optimize the design of transition metal oxide micro/nanostructures for high performance lithium storage. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000386242500084 |
Publication Date |
2016-10-06 |
|
| |
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 |
5 |
Open Access |
|
|
| |
Notes |
Z. Y. Hu and G. Van Tendeloo acknowledge support from the EC Framework 7 program ESTEEM2 (Reference 312483). |
Approved  |
Most recent IF: 3.108 |
|
| |
Call Number |
EMAT @ emat @ c:irua:138199 |
Serial |
4322 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Dabaghmanesh, S.; Saniz, R.; Neyts, E.; Partoens, B. |
|
| |
Title |
Sulfur-alloyed Cr2O3: a new p-type transparent conducting oxide host |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
7 |
Issue |
7 |
Pages |
4453-4459 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
Doped Cr2O3 has been shown to be a p-type transparent conducting oxide (TCO). Its conductivity, however, is low. As for most p-type TCOs, the main problem is the high effective hole mass due to flat valence bands. We use first-principles methods to investigate whether one can increase the valence band dispersion (i.e. reduce the hole mass) by anion alloying with sulfur, while keeping the band gap large enough for transparency. The alloying concentrations considered are given by Cr(4)SxO(6-x), with x = 1-5. To be able to describe the electronic properties of these materials accurately, we first study Cr2O3, examining critically the accuracy of different density functionals and methods, including PBE, PBE+U, HSE06, as well as perturbative approaches within the GW approximation. Our results demonstrate that Cr4S2O4 has an optical band gap of 3.08 eV and an effective hole mass of 1.8 m(e). This suggests Cr4S2O4 as a new p-type TCO host candidate. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000393751300030 |
Publication Date |
2017-01-16 |
|
| |
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 |
9 |
Open Access |
OpenAccess |
|
| |
Notes |
; This work was supported by SIM vzw, Technologiepark 935, BE-9052 Zwijnaarde, Belgium, within the InterPoCo project of the H-INT-S horizontal program. The computational resources and services used in this work were provided by the Vlaams Supercomputer Centrum (VSC) and the HPC infrastructure of the University of Antwerp. ; |
Approved |
Most recent IF: 3.108 |
|
| |
Call Number |
UA @ lucian @ c:irua:141543 |
Serial |
4528 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Sankaran, K.J.; Duc Quang Hoang; Korneychuk, S.; Kunuku, S.; Thomas, J.P.; Pobedinskas, P.; Drijkoningen, S.; Van Bael, M.K.; D'Haen, J.; Verbeeck, J.; Leou, K.-C.; Leung, K.T.; Lin, I.-N.; Haenen, K. |
|
| |
Title |
Hierarchical hexagonal boron nitride nanowall-diamond nanorod heterostructures with enhanced optoelectronic performance |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
6 |
Issue |
93 |
Pages |
90338-90346 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
A superior field electron emission (FEE) source made from a hierarchical heterostructure, where two-dimensional hexagonal boron nitride (hBN) nanowalls were coated on one-dimensional diamond nanorods (DNRs), is fabricated using a simple and scalable method. FEE characteristics of hBN-DNR display a low turn-on field of 6.0 V mu m(-1), a high field enhancement factor of 5870 and a high life-time stability of 435 min. Such an enhancement in the FEE properties of hBN-DNR derives from the distinctive material combination, i.e., high aspect ratio of the heterostructure, good electron transport from the DNR to the hBN nanowalls and efficient field emission of electrons from the hBN nanowalls. The prospective application of these heterostructures is further evidenced by enhanced microplasma devices using hBN-DNR as a cathode, in which the threshold voltage was lowered to 350 V, affirming the role of hBN-DNR in the improvement of electron emission. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000385451800044 |
Publication Date |
2016-09-12 |
|
| |
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 |
8 |
Open Access |
|
|
| |
Notes |
The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. KJ Sankaran, and P Pobedinskas are Postdoctoral Fellows of the Research Foundation-Flanders (FWO). |
Approved |
Most recent IF: 3.108 |
|
| |
Call Number |
UA @ lucian @ c:irua:144757UA @ admin @ c:irua:144757 |
Serial |
4662 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ulu Okudur, F.; D'Haen, J.; Vranken, T.; De Sloovere, D.; Verheijen, M.; Karakulina, O.M.; Abakumov, A.M.; Hadermann, J.; Van Bael, M.K.; Hardy, A. |
|
| |
Title |
Ti surface doping of LiNi0.5Mn1.5O4−δpositive electrodes for lithium ion batteries |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
8 |
Issue |
13 |
Pages |
7287-7300 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The particle surface of LiNi0.5Mn1.5O4−δ (LNMO), a Li-ion battery cathode material, has been modified by Ti cation doping through a hydrolysis–condensation reaction followed by annealing in oxygen. The effect of different annealing temperatures (500–850 °C) on the Ti distribution and electrochemical performance of the surface modified LNMO was investigated. Ti cations diffuse from the preformed amorphous ‘TiOx’ layer into the LNMO surface during annealing at 500 °C. This results in a 2–4 nm thick Ti-rich spinel surface having lower Mn and Ni content compared to the core of the LNMO particles, which was observed with scanning transmission electron microscopy coupled with compositional EDX mapping. An increase in the annealing temperature promotes the formation of a Ti bulk doped LiNi(0.5−w)Mn(1.5+w)−tTitO4 phase and Ti-rich LiNi0.5Mn1.5−yTiyO4 segregates above 750 °C. Fourier-transform infrared spectrometry indicates increasing Ni–Mn ordering with annealing temperature, for both bare and surface modified LNMO. Ti surface modified LNMO annealed at 500 °C shows a superior cyclic stability, coulombic efficiency and rate performance compared to bare LNMO annealed at 500 °C when cycled at 3.4–4.9 V vs. Li/Li+. The improvements are probably due to suppressed Ni and Mn dissolution with Ti surface doping. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000425508900064 |
Publication Date |
2018-02-13 |
|
| |
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 |
9 |
Open Access |
OpenAccess |
|
| |
Notes |
This research is supported by the Research Foundation Flanders (FWO Vlaanderen, grant number G040116N). This project receives the support of the European Union, the European Regional Development Fund ERDF, Flanders Innovation & Entrepreneurship and the Province of Limburg (project 936). Greet Cuyvers and Gilles Bonneux (UHasselt) are acknowledged for the ICP-AES sample preparation and measurements. Vera Meynen and Karen Leyssens (Antwerp University, Belgium) are acknowledged for the BET measurements. Special thanks to Bart Ruttens (UHasselt) for XRD measurements and discussions on the refinements. |
Approved |
Most recent IF: 3.108 |
|
| |
Call Number |
EMAT @ emat @c:irua:149513 |
Serial |
4905 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Kumar, N.; Shaw, P.; Razzokov, J.; Yusupov, M.; Attri, P.; Uhm, H.S.; Choi, E.H.; Bogaerts, A. |
|
| |
Title |
Enhancement of cellular glucose uptake by reactive species: a promising approach for diabetes therapy |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
8 |
Issue |
18 |
Pages |
9887-9894 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
It is generally known that antidiabetic activity is associated with an increased level of glucose uptake in adipocytes and skeletal muscle cells. However, the role of exogenous reactive oxygen and nitrogen species (RONS) in muscle development and more importantly in glucose uptake is largely unknown. We investigate the effect of RONS generated by cold atmospheric plasma (CAP) in glucose uptake. We show that the glucose uptake is significantly enhanced in differentiated L6 skeletal muscle cells after CAP treatment. We also observe a significant increase of the intracellular Ca++ and ROS level, without causing toxicity. One of the possible reasons for an elevated level of glucose uptake as well as intracellular ROS and Ca++ ions is probably the increased oxidative stress leading to glucose transport. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000430451800036 |
Publication Date |
2018-03-08 |
|
| |
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 |
1 |
Open Access |
OpenAccess |
|
| |
Notes |
We gratefully acknowledge nancial support from the Research Foundation – Flanders (FWO), grant numbers 12J5617N, 1200216N and from the European Marie Skłodowska-Curie Individual Fellowship “Anticancer-PAM” within Horizon2020 (grant number 743546). We are also thankful to the Plasma Bioscience Research Center at Kwangwoon University for providing the core facilities for the experimental work as well as nancial support by the Leading Foreign Research Institute Recruitment program (Grant # NRF-2016K1A4A3914113) through the Basic Science Research Program of the National Research Founda |
Approved |
Most recent IF: 3.108 |
|
| |
Call Number |
PLASMANT @ plasmant @c:irua:149564 |
Serial |
4909 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Tikhomirov, V.K.; Vosch, T.; Fron, E.; Rodríguez, V.D.; Velázquez, J.J.; Kirilenko, D.; Van Tendeloo, G.; Hofkens, J.; Van der Auweraer, M.; Moshchalkov, V.V. |
|
| |
Title |
Luminescence of oxyfluoride glasses co-doped with Ag nanoclusters and Yb3+ ions |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
2 |
Issue |
4 |
Pages |
1496-1501 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Bulk oxyfluoride glasses co-doped with Ag nanoclusters and Yb3+ ions have been prepared by a melt quenching technique. When excited in the absorption band of the Ag nanoclusters between 300 to 500 nm, these glasses emit a broad band characteristic of the Ag nanoclusters between 400 to 750 nm as well as an emission band between 900 to 1100 nm, originating from Yb3+ ions. The intensity ratio of the Yb3+/Ag emission bands increases with the Ag doping level at a fixed concentration of Yb3+, indicating the presence of energy transfer mechanism from the Ag nanoclusters to the Yb3+ ions. Comparison of time-resolved decay kinetics of the luminescence in the respectively Ag nanocluster-Yb3+ co-doped and single Ag nanocluster doped glasses, hints towards an energy transfer from the red and infrared emitting Ag nanoclusters to the Yb3+ ions. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000299695300038 |
Publication Date |
2011-12-19 |
|
| |
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 |
46 |
Open Access |
|
|
| |
Notes |
Fwo; Iap |
Approved |
Most recent IF: 3.108; 2012 IF: 2.562 |
|
| |
Call Number |
UA @ lucian @ c:irua:96239 |
Serial |
1856 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Lebedev, O.I.; Turner, S.; Sada, C.; Depero, L.E.; Van Tendeloo, G.; Barreca, D. |
|
| |
Title |
Fluorine doped Fe2O3 nanostructures by a one-pot plasma-assisted strategy |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
3 |
Issue |
45 |
Pages |
23762-23768 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The present work reports on the synthesis of fluorine doped Fe2O3 nanomaterials by a single-step plasma enhanced-chemical vapor deposition (PE-CVD) strategy. In particular, Fe(hfa)2TMEDA (hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine) was used as molecular source for both Fe and F in Ar/O2 plasmas. The structure, morphology and chemical composition of the synthesized nanosystems were thoroughly analyzed by two-dimensional X-ray diffraction (XRD2), field emission-scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS) and transmission electron microscopy (TEM). A suitable choice of processing parameters enabled the selective formation of α-Fe2O3 nanomaterials, characterized by an homogeneous F doping, even at 100 °C. Interestingly, a simultaneous control of the system nanoscale organization and fluorine content could be achieved by varying the sole growth temperature. The tailored properties of the resulting materials can be favourably exploited for several technological applications, ranging from photocatalysis, to photoelectrochemical cells and gas sensing. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000326395800141 |
Publication Date |
2013-10-03 |
|
| |
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 |
23 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 3.108; 2013 IF: 3.708 |
|
| |
Call Number |
UA @ lucian @ c:irua:111091 |
Serial |
1237 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Filippousi, M.; Altantzis, T.; Stefanou, G.; Betsiou, M.; Bikiaris, D.N.; Angelakeris, M.; Pavlidou, E.; Zamboulis, D.; Van Tendeloo, G. |
|
| |
Title |
Polyhedral iron oxide coreshell nanoparticles in a biodegradable polymeric matrix : preparation, characterization and application in magnetic particle hyperthermia and drug delivery |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
3 |
Issue |
46 |
Pages |
24367-24377 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Polyhedral magnetic iron oxide nanocrystals with multiple facets have been embedded in biocompatible and biodegradable polymeric matrices in order to study their structural, magnetic features and alternating-current (AC) magnetic heating efficiency. The encapsulation of iron oxide nanoparticles into a polymer matrix was confirmed by transmission electron microscopy and further corroborated by high angle annular dark field scanning transmission electron microscopy (HAADF-STEM). HAADF-STEM tomography proved that the iron oxide nanocrystals consist of well-defined polyhedral structures with multiple facets. The magnetic features were found to be in good agreement with the structural and morphological features and are maintained even after encapsulation. Furthermore, the magnetic nanoparticles inside these matrices may be considered as good candidates for biomedical applications in hyperthermia treatments because of their high heating capacity exhibited under an alternating magnetic field. The anticancer Taxol drug was encapsulated in these nanoparticles and its physical state and release rate at 37 and 42 °C was studied. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000326745100068 |
Publication Date |
2013-10-07 |
|
| |
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 |
19 |
Open Access |
|
|
| |
Notes |
Countatoms; IAP |
Approved |
Most recent IF: 3.108; 2013 IF: 3.708 |
|
| |
Call Number |
UA @ lucian @ c:irua:111395 |
Serial |
2671 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Damm, H.; Kelchtermans, A.; Bertha, A.; Van den Broeck, F.; Elen, K.; Martins, J.C.; Carleer, R.; D'Haen, J.; De Dobbelaere, C.; Hadermann, J.; Hardy, A.; Van Bael, M.K.; |
|
| |
Title |
Thermal decomposition synthesis of Al-doped ZnO nanoparticles : an in-depth study |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
3 |
Issue |
45 |
Pages |
23745-23754 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Al-doped ZnO nanoparticles are synthesized by means of a heating up solution based thermal decomposition method. The synthesis involves a reaction of zinc acetylacetonate hydrate, aluminium acetylacetonate and 1,2-hexadecanediol in the presence of oleic acid and oleyl amine. A proposed reaction mechanism from reagents to monomers is corroborated by analysis of the evolving gases using headspace GC-MS analysis. The Al-doped ZnO nanoparticles synthesized are dynamically stabilized by adsorbed oleate ions, after deprotonation of oleic acid by oleyl amine, as was found by NOESY proton NMR and complementary FTIR spectroscopy. Precession electron diffraction shows a simultaneous increase in lattice parameters with Al concentration. This, together with HAADF-STEM and EDX maps, indicates the incorporation of Al into the ZnO nanoparticles. By the combination of complementary characterization methods during all stages of the synthesis, it is concluded that Al is incorporated into the ZnO wurtzite lattice as a dopant. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000326395800139 |
Publication Date |
2013-10-18 |
|
| |
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 |
10 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.108; 2013 IF: 3.708 |
|
| |
Call Number |
UA @ lucian @ c:irua:112753 |
Serial |
3627 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Deng, S.; Verbruggen, S.W.; He, Z.; Cott, D.J.; Vereecken, P.M.; Martens, J.A.; Bals, S.; Lenaerts, S.; Detavernier, C. |
|
| |
Title |
Atomic layer deposition-based synthesis of photoactive TiO2 nanoparticle chains by using carbon nanotubes as sacrificial templates |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
4 |
Issue |
23 |
Pages |
11648-11653 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) |
|
| |
Abstract |
Highly ordered and self supported anatase TiO2 nanoparticle chains were fabricated by calcining conformally TiO2 coated multi-walled carbon nanotubes (MWCNTs). During annealing, the thin tubular TiO2 coating that was deposited onto the MWCNTs by atomic layer deposition (ALD) was transformed into chains of TiO2 nanoparticles ([similar]12 nm diameter) with an ultrahigh surface area (137 cm2 per cm2 of substrate), while at the same time the carbon from the MWCNTs was removed. Photocatalytic tests on the degradation of acetaldehyde proved that these forests of TiO2 nanoparticle chains are highly photoactive under UV light because of their well crystallized anatase phase. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000332470000017 |
Publication Date |
2014-02-14 |
|
| |
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 |
45 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; The authors wish to thank the Research Foundation – Flanders (FWO) and UGENT-GOA-01G01513 for financial support. The authors acknowledge the European Research Council for funding under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no. 239865-COCOON and no. 246791-COUNTATOMS. JAM acknowledges the Flemish government for long-term structural funding (Methusalem). ; |
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
|
| |
Call Number |
UA @ lucian @ c:irua:117298 |
Serial |
168 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Pospisilova, A.; Filippov, S.K.; Bogomolova, A.; Turner, S.; Sedlacek, O.; Matushkin, N.; Cernochova, Z.; Stepanek, P.; Hruby, M. |
|
| |
Title |
Glycogen-graft-poly(2-alkyl-2-oxazolines) – the new versatile biopolymer-based thermoresponsive macromolecular toolbox |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
4 |
Issue |
106 |
Pages |
61580-61588 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
This study is focused on thermoresponsive glycogen-graft-poly(2-alkyl-2-oxazolines), a new group of nanostructured hybrid dendrimeric stimuli-responsive polymers connecting the body's own biodegradable polysaccharidic dendrimer glycogen with the widely tuneable thermoresponsive behavior of polypeptide-analogic poly(2-alkyl-2-oxazolines), which are known to be biocompatible. Glycogen-graft-poly(2-alkyl-2-oxazolines) were prepared by a simple one-pot two-step procedure involving cationic ring-opening polymerization of 2-alkyl-2-oxazolines followed by termination of the living cationic ends with sodium glycogenate. As confirmed by light and X-ray scattering, as well as cryo-transmission electron microscopy, the grafted dendrimer structure allows easy adjustment of the cloud point temperature, the concentration dependence and nanostructure of the self-assembled phase separated polymer by crosstalk during graft composition, the graft length and the grafting density, in a very wide range. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000345656600045 |
Publication Date |
2014-11-04 |
|
| |
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 |
15 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
|
| |
Call Number |
UA @ lucian @ c:irua:122222 |
Serial |
1355 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Berdiyorov, G.R.; Peeters, F.M. |
|
| |
Title |
Influence of vacancy defects on the thermal stability of silicene: a reactive molecular dynamics study |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
4 |
Issue |
3 |
Pages |
1133-1137 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The effect of vacancy defects on the structural properties and the thermal stability of free standing silicene – a buckled structure of hexagonally arranged silicon atoms – is studied using reactive molecular dynamics simulations. Pristine silicene is found to be stable up to 1500 K, above which the system transits to a three-dimensional amorphous configuration. Vacancy defects result in local structural changes in the system and considerably reduce the thermal stability of silicene: depending on the size of the vacancy defect, the critical temperature decreases by more than 30%. However, the system is still found to be stable well above room temperature within our simulation time of 500 ps. We found that the, stability of silicene can be increased by saturating the dangling bonds at the defect edges by foreign atoms (e.g., hydrogen). |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000327868400015 |
Publication Date |
2013-11-06 |
|
| |
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 |
62 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. The authors are grateful to Prof. Adri van Duin for his support with the ReaxFF force field. ; |
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
|
| |
Call Number |
UA @ lucian @ c:irua:112829 |
Serial |
1658 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Lebedev, O.I.; Sada, C.; Turner, S.; Van Tendeloo, G.; Barreca, D. |
|
| |
Title |
Rational synthesis of F-doped iron oxides on Al2O3(0001) single crystals |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
4 |
Issue |
94 |
Pages |
52140-52146 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
A plasma enhanced-chemical vapor deposition (PE-CVD) route to Fe2O3-based materials on Al2O3(0001) single crystals at moderate growth temperatures (200-400 degrees C) is reported. The use of the fluorinated Fe(hfa)(2)TMEDA (hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N',N'-tetramethylethylenediamine) molecular precursor in Ar/O-2 plasmas enabled an in situ F-doping of iron oxide matrices, with a fluorine content tunable as a function of the adopted preparative conditions. Variations of the thermal energy supply enabled control of the system phase composition, resulting in gamma-Fe2O3 at 200 degrees C and alpha-Fe2O3 nanostructures at higher deposition temperatures. Notably, at 400 degrees C the formation of highly oriented alpha-Fe2O3 nanocolumns characterized by an epitaxial relation with the Al2O3(0001) substrate was observed. Beside fluorine content, phase composition and nano-organization, even the system optical properties and, in particular, energy gap values, could be tailored by proper modifications of processing parameters. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000344389000041 |
Publication Date |
2014-10-02 |
|
| |
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 |
4 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
|
| |
Call Number |
UA @ lucian @ c:irua:121239 |
Serial |
2813 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Lebedev, O.I.; Sada, C.; Turner, S.; Van Tendeloo, G.; Barreca, D. |
|
| |
Title |
Rational synthesis of F-doped iron oxides on Al2O3(0001) single crystals |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Rsc Advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
|
Issue |
94 |
Pages |
52140-52146 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
A plasma enhanced-chemical vapor deposition (PE-CVD) route to Fe2O3-based materials on Al2O3(0001) single crystals at moderate growth temperatures (200400 °C) is reported. The use of the fluorinated Fe(hfa)2TMEDA (hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine) molecular precursor in Ar/O2 plasmas enabled an in situ F-doping of iron oxide matrices, with a fluorine content tunable as a function of the adopted preparative conditions. Variations of the thermal energy supply enabled control of the system phase composition, resulting in γ-Fe2O3 at 200 °C and α-Fe2O3 nanostructures at higher deposition temperatures. Notably, at 400 °C the formation of highly oriented α-Fe2O3 nanocolumns characterized by an epitaxial relation with the Al2O3(0001) substrate was observed. Beside fluorine content, phase composition and nano-organization, even the system optical properties and, in particular, energy gap values, could be tailored by proper modifications of processing parameters. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000344389000041 |
Publication Date |
2014-10-02 |
|
| |
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 |
4 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
|
| |
Call Number |
UA @ lucian @ c:irua:119529 |
Serial |
2814 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Kerkhofs, S.; Leroux, F.; Allouche, L.; Mellaerts, R.; Jammaer, J.; Aerts, A.; Kirschhock, C.E.A.; Magusin, P.C.M.M.; Taulelle, F.; Bals, S.; Van Tendeloo, G.; Martens, J.A.; |
|
| |
Title |
Single-step alcohol-free synthesis of coreshell nanoparticles of \gamma-casein micelles and silica |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
4 |
Issue |
49 |
Pages |
25650-25657 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
A new, single-step protocol for wrapping individual nanosized β-casein micelles with silica is presented. This biomolecule-friendly synthesis proceeds at low protein concentration at almost neutral pH, and makes use of sodium silicate instead of the common silicon alkoxides. This way, formation of potentially protein-denaturizing alcohols can be avoided. The pH of the citrate-buffered synthesis medium is close to the isoelectric point of β-casein, which favours micelle formation. A limited amount of sodium silicate is added to the protein micelle suspension, to form a thin silica coating around the β-casein micelles. The size distribution of the resulting proteinsilica structures was characterized using DLS and SAXS, as well as 1H NMR DOSY with a dedicated pulsed-field gradient cryo-probehead to cope with the low protein concentration. The degree of silica-condensation was investigated by 29Si MAS NMR, and the nanostructure was revealed by advanced electron microscopy techniques such as ESEM and HAADF-STEM. As indicated by the combined characterization results, a silica shell of 2 nm is formed around individual β-casein micelles giving rise to separate protein coresilica shell nanoparticles of 17 nm diameter. This alcohol-free method at mild temperature and pH is potentially suited for packing protein molecules into bio-compatible silica nanocapsules for a variety of applications in biosensing, therapeutic protein delivery and biocatalysis. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000338434500025 |
Publication Date |
2014-05-29 |
|
| |
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 |
3 |
Open Access |
OpenAccess |
|
| |
Notes |
Fwo; 262348 Esmi; 335078 Colouratom; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:can); |
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
|
| |
Call Number |
UA @ lucian @ c:irua:125382 |
Serial |
3027 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Van Eynde, E.; Lenaerts, B.; Tytgat, T.; Verbruggen, S.W.; Hauchecorne, B.; Blust, R.; Lenaerts, S. |
|
| |
Title |
Effect of pretreatment and temperature on the properties of Pinnularia biosilica frustules |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
4 |
Issue |
|
Pages |
56200-56206 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
|
| |
Abstract |
Diatoms are unicellular microalgae that self-assemble an intricate porous silica cell wall, called frustule. Diatom frustules possess a unique combination of physical and chemical properties (chemical inertness, high mechanical strength, large surface area, low density, good porosity and highly ordered features on the nano-to-micro scale) making diatom frustules suited for many nanotechnological applications. For most proposed applications the organic material covering the frustules needs to be removed. In this paper we investigate the effect of different frustule cleaning methods (drying, autoclavation, SDS/EDTA treatment, H2O2 treatment and HNO3 treatment) and subsequent heat treatment at different temperatures (105 °C, 350 °C, 550 °C and 750 °C) on the material characteristics of the diatom Pinnularia sp. Material characteristics under study are morphology, surface area, pore size, elemental composition and organic content. The cleaned Pinnularia frustules are subsequently investigated as adsorbents to remove methylene blue (MB) from aqueous solution. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000344997800060 |
Publication Date |
2014-10-23 |
|
| |
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 |
10 |
Open Access |
|
|
| |
Notes |
; ; |
Approved |
Most recent IF: 3.108; 2014 IF: 3.840 |
|
| |
Call Number |
UA @ admin @ c:irua:121377 |
Serial |
5945 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Leus, K.; Concepcion, P.; Vandichel, M.; Meledina, M.; Grirrane, A.; Esquivel, D.; Turner, S.; Poelman, D.; Waroquier, M.; Van Speybroeck, V.; Van Tendeloo, G.; García, H.; Van Der Voort, P.; |
|
| |
Title |
Au@UiO-66 : a base free oxidation catalyst |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
5 |
Issue |
5 |
Pages |
22334-22342 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We present the in situ synthesis of Au nanoparticles within the Zr based Metal Organic Framework, UiO-66. The resulting Au@UiO-66 materials were characterized by means of N-2 sorption, XRPD, UV-Vis, XRF, XPS and TEM analysis. The Au nanoparticles (NP) are homogeneously distributed along the UiO-66 host matrix when using NaBH4 or H-2 as reducing agents. The Au@UiO-66 materials were evaluated as catalysts in the oxidation of benzyl alcohol and benzyl amine employing O-2 as oxidant. The Au@MOF materials exhibit a very high selectivity towards the ketone (up to 100%). Regenerability and stability tests demonstrate that the Au@UiO-66 catalyst can be recycled with a negligible loss of Au species and no loss of crystallinity. In situ IR measurements of UiO-66 and Au@UiO-66-NaBH4, before and after treatment with alcohol, showed an increase in IR bands that can be assigned to a combination of physisorbed and chemisorbed alcohol species. This was confirmed by velocity power spectra obtained from the molecular dynamics simulations. Active peroxo and oxo species on Au could be visualized with Raman analysis. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000350643700005 |
Publication Date |
2015-02-19 |
|
| |
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 |
38 |
Open Access |
|
|
| |
Notes |
FWO; Hercules; 246791 COUNTATOMS; IAP-PAI |
Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
|
| |
Call Number |
c:irua:125431 |
Serial |
207 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ullah, S.; Hussain, A.; Syed, W.A.; Saqlain, M.A.; Ahmad, I.; Leenaerts, O.; Karim, A. |
|
| |
Title |
Band-gap tuning of graphene by Be doping and Be, B co-doping : a DFT study |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
| |
Volume |
5 |
Issue |
5 |
Pages |
55762-55773 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
First-principles density functional theory (DFT) calculations were carried out to investigate the structural and electronic properties of beryllium (Be) doped and Be and boron (B) co-doped graphene systems. We observed that not only the concentration of impurity atoms is important to tune the band-gap to some desired level, but also the specific substitution sites play a key role. In our system, which consists of 32 atoms, a maximum of 4Be and, in the co-doped state, 2Be and 3B atom substitutions are investigated. Both dopants are electron deficient relative to C atoms and cause the Fermi level to shift downward (p-type doping). A maximum band gap of 1.44 eV can be achieved on incorporation of 4Be atoms. The introduction of Be is more sensitive in terms of geometry and stability than B. However, in opening the energy gap, Be is more effective than B and N (nitrogen). Our results offer the possibility to modify the band-gap of graphene sufficiently for utilization in diverse electronic device applications. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000357803200018 |
Publication Date |
2015-06-17 |
|
| |
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 |
33 |
Open Access |
|
|
| |
Notes |
; ; |
Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
|
| |
Call Number |
c:irua:127167 |
Serial |
216 |
|
| Permanent link to this record |
| |
|
| |
|
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 |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
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 |
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 |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000352789500026 |
Publication Date |
2015-03-19 |
|
| |
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 |
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 |
| |
|
| |
|
Author |
Anitha, A.; Brasoveanu, A.; Duarte, M.; Hughes, S.; Daubechies, I.; Dik, J.; Janssens, K.; Alfeld, M. |
|
| |
Title |
Restoration of X-ray fluorescence images of hidden paintings |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Signal processing |
Abbreviated Journal |
Signal Process |
|
| |
Volume |
93 |
Issue |
3 |
Pages |
592-604 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
This paper describes our methods for repairing and restoring images of hidden paintings (paintings that have been painted over and are now covered by a new surface painting) that have been obtained via noninvasive X-ray fluorescence imaging of their canvases. This recently developed imaging technique measures the concentrations of various chemical elements at each two-dimensional spatial location across the canvas. These concentrations in turn result from pigments present both in the surface painting and in the hidden painting beneath. These X-ray fluorescence images provide the best available data from which to noninvasively study a hidden painting. However, they are typically marred by artifacts of the imaging process, features of the surface painting, and areas of information loss. Repairing and restoring these images thus consists of three stages: (1) repairing acquisition artifacts in the dataset, (2) removal of features in the images that result from the surface painting rather than the hidden painting, and (3) identification and repair of areas of information loss. We describe methods we have developed to address each of these stages: a total-variation minimization approach to artifact correction, a novel method for underdetermined blind source separation with multimodal side information to address surface feature removal, and two application-specific new methods for automatically identifying particularly thick or X-ray absorbent surface features in the painting. Finally, we demonstrate the results of our methods on a hidden painting by the artist Vincent van Gogh. (C) 2012 Elsevier B.V. All rights reserved. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000312521400007 |
Publication Date |
2012-10-13 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0165-1684 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.11 |
Times cited |
13 |
Open Access |
|
|
| |
Notes |
; Marco F. Duarte was supported during this research by NSF Supplemental Funding DMS-0439872 to UCLA-IPAM, PI: R. Caflisch. Matthias Alfeld receives support in the form of a Ph.D. fellowship of the Research Foundation Flanders (FWO). This research was also supported by the Interuniversity Attraction Poles Programme Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ; |
Approved |
Most recent IF: 3.11; 2013 IF: 2.238 |
|
| |
Call Number |
UA @ admin @ c:irua:105921 |
Serial |
5817 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Bittencourt, C.; Krüger, P.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Ewels, C.; Umek, P.; Guttmann, P. |
|
| |
Title |
Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
|
| |
Volume |
3 |
Issue |
|
Pages |
789-797 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Recent advances in near-edge X-ray-absorption fine-structure spectroscopy coupled with transmission X-ray microscopy (NEXAFS-TXM) allow large-area mapping investigations of individual nano-objects with spectral resolution up to E/Delta E = 104 and spatial resolution approaching 10 nm. While the state-of-the-art spatial resolution of X-ray microscopy is limited by nanostructuring process constrains of the objective zone plate, we show here that it is possible to overcome this through close coupling with high-level theoretical modelling. Taking the example of isolated bundles of hydrothermally prepared sodium titanate nanotubes ((Na,H)TiNTs) we are able to unravel the complex nanoscale structure from the NEXAFS-TXM data using multichannel multiple-scattering calculations, to the extent of being able to associate specific spectral features in the O K-edge and Ti L-edge with oxygen atoms in distinct sites within the lattice. These can even be distinguished from the contribution of different hydroxyl groups to the electronic structure of the (Na,H)TiNTs. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000311482400001 |
Publication Date |
2012-11-23 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2190-4286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.127 |
Times cited |
13 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.127; 2012 IF: 2.374 |
|
| |
Call Number |
UA @ lucian @ c:irua:105140 |
Serial |
3684 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Bittencourt, C.; Hitchock, A.P.; Ke, X.; Van Tendeloo, G.; Ewels, C.P.; Guttmann, P. |
|
| |
Title |
X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
|
| |
Volume |
3 |
Issue |
|
Pages |
345-350 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We demonstrate that near-edge X-ray-absorption fine-structure spectra combined with full-field transmission X-ray microscopy can be used to study the electronic structure of graphite flakes consisting of a few graphene layers. The flake was produced by exfoliation using sodium cholate and then isolated by means of density-gradient ultracentrifugation. An image sequence around the carbon K-edge, analyzed by using reference spectra for the in-plane and out-of-plane regions of the sample, is used to map and spectrally characterize the flat and folded regions of the flake. Additional spectral features in both π and σ regions are observed, which may be related to the presence of topological defects. Doping by metal impurities that were present in the original exfoliated graphite is indicated by the presence of a pre-edge signal at 284.2 eV. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000303243400001 |
Publication Date |
2012-04-25 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2190-4286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.127 |
Times cited |
15 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.127; 2012 IF: 2.374 |
|
| |
Call Number |
UA @ lucian @ c:irua:97703 |
Serial |
3924 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ke, X.; Bittencourt, C.; Bals, S.; Van Tendeloo, G. |
|
| |
Title |
Low-dose patterning of platinum nanoclusters on carbon nanotubes by focused-electron-beam-induced deposition as studied by TEM |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
|
| |
Volume |
4 |
Issue |
|
Pages |
77-86 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Focused-electron-beam-induced deposition (FEBID) is used as a direct-write approach to decorate ultrasmall Pt nanoclusters on carbon nanotubes at selected sites in a straightforward maskless manner. The as-deposited nanostructures are studied by transmission electron microscopy (TEM) in 2D and 3D, demonstrating that the Pt nanoclusters are well-dispersed, covering the selected areas of the CNT surface completely. The ability of FEBID to graft nanoclusters on multiple sides, through an electron-transparent target within one step, is unique as a physical deposition method. Using high-resolution TEM we have shown that the CNT structure can be well preserved thanks to the low dose used in FEBID. By tuning the electron-beam parameters, the density and distribution of the nanoclusters can be controlled. The purity of as-deposited nanoclusters can be improved by low-energy electron irradiation at room temperature. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000314499700001 |
Publication Date |
2013-02-04 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2190-4286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.127 |
Times cited |
12 |
Open Access |
|
|
| |
Notes |
262348 ESMI; 246791 COUNTATOMS; FWO G002410N; ESF Cost Action NanoTP MP0901 |
Approved |
Most recent IF: 3.127; 2013 IF: 2.332 |
|
| |
Call Number |
UA @ lucian @ c:irua:106187 |
Serial |
1848 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Mordvinova, N.; Emelin, P.; Vinokurov, A.; Dorofeev, S.; Abakumov, A.; Kuznetsova, T. |
|
| |
Title |
Surface processes during purification of InP quantum dots |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
|
| |
Volume |
5 |
Issue |
|
Pages |
1220-1225 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)(3) during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of post-synthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000339912400002 |
Publication Date |
2014-08-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2190-4286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.127 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.127; 2014 IF: 2.670 |
|
| |
Call Number |
UA @ lucian @ c:irua:118748 |
Serial |
3397 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vidick, D.; Ke, X.; Devillers, M.; Poleunis, C.; Delcorte, A.; Moggi, P.; Van Tendeloo, G.; Hermans, S. |
|
| |
Title |
Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
|
| |
Volume |
6 |
Issue |
6 |
Pages |
1287-1297 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Heterometal clusters containing Ru and Au, Co and/or Pt are anchored onto carbon nanotubes and nanofibers functionalized with chelating phosphine groups. The cluster anchoring yield is related to the amount of phosphine groups available on the nanocarbon surface. The ligands of the anchored molecular species are then removed by gentle thermal treatment in order to form nanoparticles. In the case of Au-containing clusters, removal of gold atoms from the clusters and agglomeration leads to a bimodal distribution of nanoparticles at the nanocarbon surface. In the case of Ru-Pt species, anchoring occurs without reorganization through a ligand exchange mechanism. After thermal treatment, ultrasmall (1-3 nm) bimetal Ru-Pt nanoparticles are formed on the surface of the nanocarbons. Characterization by high resolution transmission electron microscopy (HRTEM) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) confirms their bimetal nature on the nanoscale. The obtained bimetal nanoparticles supported on nanocarbon were tested as catalysts in ammonia synthesis and are shown to be active at low temperature and atmospheric pressure with very low Ru loading. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000355908400001 |
Publication Date |
2015-06-10 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2190-4286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.127 |
Times cited |
7 |
Open Access |
|
|
| |
Notes |
246791 Countatoms; 262348 Esmi |
Approved |
Most recent IF: 3.127; 2015 IF: 2.670 |
|
| |
Call Number |
c:irua:126431 |
Serial |
1420 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ke, X.; Bittencourt, C.; Van Tendeloo, G. |
|
| |
Title |
Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
|
| |
Volume |
6 |
Issue |
6 |
Pages |
1541-1557 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
A major revolution for electron microscopy in the past decade is the introduction of aberration correction, which enables one to increase both the spatial resolution and the energy resolution to the optical limit. Aberration correction has contributed significantly to the imaging at low operating voltages. This is crucial for carbon-based nanomaterials which are sensitive to electron irradiation. The research of carbon nanomaterials and nanohybrids, in particular the fundamental understanding of defects and interfaces, can now be carried out in unprecedented detail by aberration-corrected transmission electron microscopy (AC-TEM). This review discusses new possibilities and limits of AC-TEM at low voltage, including the structural imaging at atomic resolution, in three dimensions and spectroscopic investigation of chemistry and bonding. In situ TEM of carbon-based nanomaterials is discussed and illustrated through recent reports with particular emphasis on the underlying physics of interactions between electrons and carbon atoms. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000357977300001 |
Publication Date |
2015-07-16 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2190-4286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.127 |
Times cited |
10 |
Open Access |
|
|
| |
Notes |
246791 Countatoms |
Approved |
Most recent IF: 3.127; 2015 IF: 2.670 |
|
| |
Call Number |
c:irua:126857 |
Serial |
2682 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Bez, R.; Zehani, K.; Batuk, M.; Van Tendeloo, G.; Mliki, N.; Bessais, L. |
|
| |
Title |
Structure and magnetic properties of Sm(Fe,Si)(9)C/alpha-Fe nanocomposite magnets |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Journal of alloys and compounds |
Abbreviated Journal |
J Alloy Compd |
|
| |
Volume |
695 |
Issue |
695 |
Pages |
810-817 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
SmFe8.75 Si-0.25 C/alpha-Fe nanocomposites have been successfully synthesized using high energy milling, followed by annealing at 750 degrees C. The crystal structure of these compounds was characterized by the Rietveld method using powder X-ray diffraction data. By increasing the concentration of Sm, we observed a decrease in the amount of alpha-Fe phase. The morphology of the samples was determined by scanning and transmission electron microscopy. The average grain size is about 20 nm. The magnetic properties were investigated at room temperature and at 10 K. A ferromagnetic behavior was observed in all samples at both temperatures. An increase of the soft magnetic phase alpha-Fe induced an increase in the magnetization and a decrease in coercivity. (C) 2016 Elsevier B.V. All rights reserved. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
| |
Language |
|
Wos |
000391817600098 |
Publication Date |
2016-10-19 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.133 |
Times cited |
1 |
Open Access |
Not_Open_Access |
|
| |
Notes |
; This work is main supported by the CNRS and the “Ministere de l'Enseignement Superieur, de la Recherche Scientifique” (LR99ES17) (Tunisia), PHC-Utique (Project 11/G 1301) and PHC-Maghreb (Project 15MAG07). The authors acknowledge the French SIE doctoral school of the University Paris Est for its support. ; |
Approved |
Most recent IF: 3.133 |
|
| |
Call Number |
UA @ lucian @ c:irua:140380 |
Serial |
4448 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Batuk, D.; Batuk, M.; Morozov, V.A.; Meert, K.W.; Smet, P.F.; Poelman, D.; Abakumov, A.M.; Hadermann, J. |
|
| |
Title |
Effect of cation vacancies on the crystal structure and luminescent properties of Ca(0.85-1.5x)Gd(x)Eu(0.1)_(0.05+0.5x)WO(4) (0<x<0.567) scheelite-based red phosphors |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Journal of alloys and compounds |
Abbreviated Journal |
J Alloy Compd |
|
| |
Volume |
706 |
Issue |
706 |
Pages |
358-369 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The Ca0.85-1.5xGdxEu0.1_0.05-0.5xWO4 (0 < x < 0.567) series of cation-deficient scheelites is investigated to unveil the influence of the cation vacancies on the crystal structure and luminescent properties. The concentration of the vacancies is varied by the heterovalent substitution of Gd3+ for Ca2+, keeping the concentration of the Eu3+ luminescent centers constant in all compounds of the series. The crystal structure of the materials is studied using a combination of transmission electron microscopy and synchrotron X-ray powder diffraction. At low vacancy concentration (x = 0.1, 0.2), cations and cation vacancies are randomly distributed in the structure, and the materials preserve the I41/a symmetry of the parent scheelite structure [x = 0.1: a = 5.25151(1) Å, c = 11.39479(2) Å; x = 0.2: a = 5.25042(1) Å, c = 11.41335(2) Å]. At higher concentration, the cation-vacancy ordering gives rise to incommensurately modulated structures. The x = 0.3 structure has a (3 + 2)D tetragonal symmetry [superspace group I41/a(a,b,0)00(-b,a,0)00, a = 5.24700(1) Å, c = 11.45514(3) Å, q1 = 0.51637(14)a* + 0.80761(13)b*, q2 = -0.80761a* + 0.51637b*]. At x = 0.4, the scheelite basic cell undergoes a monoclinic distortion with the formation of the (3 + 1)D structure [superspace group I2/b(a,b,0)00, a = 5.23757(1) Å, b = 5.25035(1) Å, c = 11.45750(2) Å, g = 90.5120(2) o, q = 0.54206(8)a* + 0.79330(8)b*]. In both structures, the antiphase Ca and (Gd,Eu) occupancy modulations indicate that the ordering between the A cations and vacancies also induces partial Ca/(Gd,Eu) cation ordering. Further increase of the Gd3þ content up to x = 0.567 leads to the formation of a monoclinic phase (space group C2/c) with the Eu2/3WO4-type structure. Despite the difference in the cation-vacancy ordering patterns, all materials in the series demonstrate very similar quantum efficiency and luminescence decay lifetimes. However, the difference in the local coordination environment of the A cation species noticeably affects the line width and the multiplet splitting of the 4f6-4f6 transitions. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000397997300045 |
Publication Date |
2017-02-16 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.133 |
Times cited |
2 |
Open Access |
OpenAccess |
|
| |
Notes |
This research was supported by FWO (Flanders Research Foundation, project G039211N). V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741).We are grateful to the ESRF for granting the beamtime at the ID22 beamline and to Andy Fitch for the support during the experiment. |
Approved |
Most recent IF: 3.133 |
|
| |
Call Number |
EMAT @ emat @ c:irua:142367 |
Serial |
4581 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M. |
|
| |
Title |
Cobalt location in p -CoO x / n -SnO 2 nanocomposites: Correlation with gas sensor performances |
Type |
A1 Journal Article |
| |
Year |
2017 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
|
| |
Volume |
721 |
Issue |
|
Pages |
249-260 |
|
| |
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
| |
Abstract |
Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000405252400030 |
Publication Date |
2017-06-02 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.133 |
Times cited |
|
Open Access |
Not_Open_Access |
|
| |
Notes |
This work was supported by ERA-Net.Plus grant N 096 FONSENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University. |
Approved |
Most recent IF: 3.133 |
|
| |
Call Number |
EMAT @ emat @ |
Serial |
4711 |
|
| Permanent link to this record |
