| Records |
| Author |
Zhou, S.; Xu, W.; Xiao, Y.; Xiao, H.; Zhang, J.; Wang, Z.; He, G.; Liu, J.; Li, Y.; Peeters, F.M. |
| Title |
Influence of neutron irradiation on X-ray diffraction, Raman spectrum and photoluminescence from pyrolytic and hot-pressed hexagonal boron nitride |
Type |
A1 Journal article |
Year  |
2023 |
Publication |
Journal of luminescence |
Abbreviated Journal |
|
| Volume |
263 |
Issue |
|
Pages |
120118-8 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Hexagonal boron nitride (hBN) is considered as an ideal semiconductor material for solid-state neutron detector, owing to its large neutron scattering section because of the low atomic number of B and excellent physical properties. Here we study the influence of neutron irradiation on crystal structure and on intermediate energy state (IMES) levels induced by the presence of impurities and defects in hBN. Large-size and thick pyrolytic and hot-pressed hBN (PBN and HBN) samples, which can be directly applied for neutron detector devices, are prepared and bombarded by neutrons with different irradiation fluences. The SEM and TEM are used to observe the sample difference of PBN and HBN. X-ray diffraction and Raman spectroscopy are applied to examine the influence of neutron irradiation on lattice structures along different crystal directions of PBN and HBN samples. Photoluminescence (PL) is employed to study the effect of neutron irradiation on IMESs in these samples. We find that the neutron irradiation does not alter the in-plane lattice structures of both PBN and HBN samples, but it can release the inter-layer tensions induced by sample growth of the PBN samples. Interestingly and surprisingly, the neutron irradiation does not affect the IMES levels responsible for PL generation, where PL is attributed mainly from phonon-assisted radiative electron-hole coupling for both PBN and HBN samples. Furthermore, the results indicate that the neutron irradiation can weaken the effective carrier-phonon coupling and exciton transitions in PBN and HBN samples. Overall, both PBN and HBN samples show some degree of the resistance to neutron irradiation in terms of these basic physical properties. The interesting and important findings from this work can help us to gain an in-depth understanding of the influence of neutron irradiation on basic physical properties of hBN materials. These effects can be taken into account when designing and applying the hBN materials for neutron detectors. |
| 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 |
001077086300001 |
Publication Date |
2023-08-09 |
| 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 |
0022-2313 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
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Approved |
no |
| Call Number |
UA @ admin @ c:irua:200393 |
Serial |
9047 |
| Permanent link to this record |
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| |
| Author |
Mijin, S.D.; Baum, A.; Bekaert, J.; Solajic, A.; Pesic, J.; Liu, Y.; He, G.; Milošević, M.V.; Petrovic, C.; Popovic, Z., V; Hackl, R.; Lazarevic, N. |
| Title |
Probing charge density wave phases and the Mott transition in 1T-TaS₂I by inelastic light scattering |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
103 |
Issue |
24 |
Pages |
245133 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We present a polarization-resolved, high-resolution Raman scattering study of the three consecutive charge density wave (CDW) regimes in 1T-TaS2 single crystals, supported by ab initio calculations. Our analysis of the spectra within the low-temperature commensurate (C-CDW) regime shows P (3) over bar symmetry of the system, thus excluding the previously proposed triclinic stacking of the “star-of-David” structure, and promoting trigonal or hexagonal stacking instead. The spectra of the high-temperature incommensurate (IC-CDW) phase directly project the phonon density of states due to the breaking of the translational invariance, supplemented by sizable electron-phonon coupling. Between 200 and 352 K, our Raman spectra show contributions from both the IC-CDW and the C-CDW phases, indicating their coexistence in the so-called nearly commensurate (NC-CDW) phase. The temperature dependence of the symmetry-resolved Raman conductivity indicates the stepwise reduction of the density of states in the CDW phases, followed by a Mott transition within the C-CDW phase. We determine the size of the Mott gap to be Omega(gap) approximate to 170-190 meV, and track its temperature dependence. |
| 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 |
000664450500002 |
Publication Date |
2021-06-22 |
| 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 |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
4 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:179664 |
Serial |
7015 |
| Permanent link to this record |
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| |
| Author |
Chee, S.-S.; Greboval, C.; Vale Magalhaes, D.; Ramade, J.; Chu, A.; Qu, J.; Rastogi, P.; Khalili, A.; Dang, T.H.; Dabard, C.; Prado, Y.; Patriarche, G.; Chaste, J.; Rosticher, M.; Bals, S.; Delerue, C.; Lhuillier, E. |
| Title |
Correlating structure and detection properties in HgTe nanocrystal films |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
| Volume |
21 |
Issue |
10 |
Pages |
4145-4151 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
HgTe nanocrystals (NCs) enable broadly tunable infrared absorption, now commonly used to design light sensors. This material tends to grow under multipodic shapes and does not present well-defined size distributions. Such point generates traps and reduces the particle packing, leading to a reduced mobility. It is thus highly desirable to comprehensively explore the effect of the shape on their performance. Here, we show, using a combination of electron tomography and tight binding simulations, that the charge dissociation is strong within HgTe NCs, but poorly shape dependent. Then, we design a dual-gate field-effect-transistor made of tripod HgTe NCs and use it to generate a planar p-n junction, offering more tunability than its vertical geometry counterpart. Interestingly, the performance of the tripods is higher than sphere ones, and this can be correlated with a stronger Te excess in the case of sphere shapes which is responsible for a higher hole trap 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 |
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Editor |
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| Language |
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Wos |
000657242300002 |
Publication Date |
2021-05-06 |
| Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.712 |
Times cited |
20 |
Open Access |
OpenAccess |
| Notes |
The project is supported by ERC starting grant blackQD (Grant No. 756225) and consolidator grant Realnano (815128). This project has received funding from the European Commission (Grant 731019, EUSMI). We acknowledge the use of cleanroom facilities from the “Centrale de Proximité Paris-Centre”. This work has been supported by the Region Ile-de-France in the framework of DIM Nano-K (Grant dopQD). This work was supported by French state funds managed by the ANR within the Investissements d’Avenir programme under reference ANR11-IDEX-0004-02, and more specifically within the framework of the Cluster of Excellence MATISSE and also by grants IPERNano2 (ANR-18CE30-0023-01), Copin (ANR-19-CE24- 0022), Frontal (ANR-19-CE09-0017), Graskop (ANR-19- CE09-0026), and NITQuantum (ANR-20-ASTR-0008-01). A.C. thanks Agence innovation defense for Ph.D. funding; sygmaSB |
Approved |
Most recent IF: 12.712 |
| Call Number |
UA @ admin @ c:irua:179127 |
Serial |
6837 |
| Permanent link to this record |
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| Author |
Tschulkow, M.; Compernolle, T.; Van den Bosch, S.; Van Aelst, J.; Storms, I.; Van Dael, M.; Van den Bossche, G.; Sels, B.; Van Passel, S. |
| Title |
Integrated techno-economic assessment of a biorefinery process: The high-end valorization of the lignocellulosic fraction in wood streams |
Type |
A1 Journal Article |
| Year |
2020 |
Publication |
Journal Of Cleaner Production |
Abbreviated Journal |
J Clean Prod |
| Volume |
266 |
Issue |
|
Pages |
122022 |
| Keywords |
A1 Journal Article; Engineering Management (ENM) ; |
| Abstract |
A new lignin-first biorefinery with a reductive catalytic fractionation process, which targets the valorization of the lignin and the carbohydrate fraction into higher value end-products, is currently being designed. To identify the various R&D drivers for projects with a low technology readiness level (TRL), we developed an integrated techno-economic assessment (TEA) that directly integrates the results of lab studies with economic costs and benefits. Furthermore, different linkages are made to upstream wood availability and downstream demand to understand its fit into existing wood value chains. By making the relations across the wood value chain explicit within the integrated TEA, we find that the scale of the plant, the feedstock-specific output quantities, and output prices highly determine the economic feasibility. Furthermore, this detailed analysis reveals the importance of assessing different types of feedstock. If only virgin wood is available as feedstock, minimum capacity levels between 190 and 234 kilotons per year are needed for the investment to be profitable. Waste wood proves to be the most profitable feedstock with an NPV of M€ 59 and an IRR of 26%. Using only waste wood as feedstock makes the investment profitable at a lower capacity level of 80 kilotons per year and economic shocks can be absorbed. Based on these results we show that an integrated and detailed TEA is indispensable to define future development paths for early-stage, innovative technologies. |
| 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 |
000573461000008 |
Publication Date |
2020-05-07 |
| 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 |
0959-6526 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
11.1 |
Times cited |
|
Open Access |
|
| Notes |
This project has received funding from the Research FoundationFlanders (FWO)-SBO BIOWOOD project. Tine Compernolle thanksthe (FWO) for funding her postdoctoral mandate with Grantnumber 12M7417N. G. V.d.B. acknowledges funding from FISCH-ICON project MAIA. J.V.A. and S.V.d.B acknowledge Flanders Inno-vation&Entrepreneurship (VLAIO) for their innovation mandate. |
Approved |
Most recent IF: 11.1; 2020 IF: 5.715 |
| Call Number |
ENM @ enm @c:irua:170069 |
Serial |
6383 |
| Permanent link to this record |
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| Author |
Cremers, V.; Rampelberg, G.; Barhoum, A.; Walters, P.; Claes, N.; Oliveira, T.M. de; Assche, G.V.; Bals, S.; Dendooven, J.; Detavernier, C. |
| Title |
Oxidation barrier of Cu and Fe powder by Atomic Layer Deposition |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Surface and coatings technology |
Abbreviated Journal |
Surf Coat Tech |
| Volume |
349 |
Issue |
349 |
Pages |
1032-1041 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Atomic layer deposition (ALD) is a vapor based technique which allows to deposit uniform, conformal films with a thickness control at the atomic scale. In this research, Al 2 O 3 coatings were deposited on micrometer-sized Fe and Cu powder (particles) using the thermal trimethylaluminum (TMA)/ water (H 2 O) process in a rotary pump-type ALD reactor. Rotation of the powder during deposition was required to obtain a pinhole-free ALD coating. The protective nature of the coating was evaluated by quantifying its effectiveness in protecting the metal particles during oxidative annealing treatments. The Al 2 O 3 coated powders were annealed in ambient air while in-situ thermogravimetric analysis (TGA) and in-situ x-ray diffraction (XRD) data were acquired. The thermal stability of a series of Cu and Fe powder with different Al 2 O 3 thicknesses were determined with TGA. In both samples a clear shift in oxidation temperature is visible. For Cu and Fe powder coated with 25 nm Al 2 O 3 , we observed an increase of the oxidation temperature with 300-400°C. For the Cu powder a thin film of only 8 nm is required to obtain an initial increase in oxidation temperature of 200°C. In contrast, for Fe powder a thicker coating of 25 nm is required. In both cases, the oxidation temperature increases with increasing thickness of the Al 2 O 3 coating. These results illustrate that the Al 2 O 3 thin film, deposited by the thermal ALD process (TMA/H 2 O) can be an efficient and pinhole-free barrier layer for micrometer-sized powder particles, provided that the powder is properly agitated during the process to ensure sufficient vapour-solid interaction. |
| 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 |
000441492600108 |
Publication Date |
2018-06-25 |
| 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 |
0257-8972 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.589 |
Times cited |
10 |
Open Access |
OpenAccess |
| Notes |
The authors acknowledge financial support from the Strategic Initiative Materials in Flanders (SIM, SBO-FUNC project) and the Special Research Fund BOF of Ghent University (GOA 01G01513). J. D. acknowledges the Research Foundation Flanders (FWO-Vlaanderen) for a postdoctoral fellowship. N.C. and S.B. acknowledge financial support from European Research Council (ERC Starting Grant 335078-COLOURATOMS). The authors acknowledge S. Goeteyn for the assistance in preliminary depositions. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); ecas_sara |
Approved |
Most recent IF: 2.589 |
| Call Number |
EMAT @ emat @c:irua:152174UA @ admin @ c:irua:152174 |
Serial |
4994 |
| Permanent link to this record |
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| Author |
Voorhaar, L.; Diaz, M.M.; Leroux, F.; Rogers, S.; Abakumov, A.M.; Van Tendeloo, G.; Van Assche, G.; Van Mele, B.; Hoogenboom, R. |
| Title |
Supramolecular thermoplastics and thermoplastic elastomer materials with self-healing ability based on oligomeric charged triblock copolymers |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
NPG Asia materials |
Abbreviated Journal |
Npg Asia Mater |
| Volume |
9 |
Issue |
|
Pages |
e385 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Supramolecular polymeric materials constitute a unique class of materials held together by non-covalent interactions. These dynamic supramolecular interactions can provide unique properties such as a strong decrease in viscosity upon relatively mild heating, as well as self-healing ability. In this study we demonstrate the unique mechanical properties of phase-separated electrostatic supramolecular materials based on mixing of low molar mass, oligomeric, ABA-triblock copolyacrylates with oppositely charged outer blocks. In case of well-chosen mixtures and block lengths, the charged blocks are phase separated from the uncharged matrix in a hexagonally packed nanomorphology as observed by transmission electron microscopy. Thermal and mechanical analysis of the material shows that the charged sections have a T-g closely beyond room temperature, whereas the material shows an elastic response at temperatures far above this T-g ascribed to the electrostatic supramolecular interactions. A broad set of materials having systematic variations in triblock copolymer structures was used to provide insights in the mechanical properties and and self-healing ability in correlation with the nanomorphology of the 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 |
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Editor |
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| Language |
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Wos |
000402065300005 |
Publication Date |
2017-05-26 |
| 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 |
1884-4049; 1884-4057 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.157 |
Times cited |
8 |
Open Access |
OpenAccess |
| Notes |
; This research was conducted in the framework of the SIM-SHE/NAPROM project and SIM is gratefully acknowledged for the financial support. ; |
Approved |
Most recent IF: 9.157 |
| Call Number |
UA @ lucian @ c:irua:144263 |
Serial |
4691 |
| Permanent link to this record |
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| Author |
Barhoum, A.; Van Assche, G.; Rahier, H.; Fleisch, M.; Bals, S.; Delplancked, M.-P.; Leroux, F.; Bahnemann, D. |
| Title |
Sol-gel hot injection synthesis of ZnO nanoparticles into a porous silica matrix and reaction mechanism |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Materials & design |
Abbreviated Journal |
Mater Design |
| Volume |
119 |
Issue |
119 |
Pages |
270-276 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Despite the enormous interest in the properties and applications of porous silica matrix, only a few attempts have been reported to deposit metal and metal oxide nanoparticles (NPs) inside the porous silica matrix. We report a simple approach (i.e. sol-gel hot injection) for insitu synthesis of ZnO NPs inside a porous silica matrix. Control of the Zn:Si molar ratio, reaction temperature, pH value, and annealing temperature permits formation of ZnO NPs (<= 10 nm) inside a porous silica particles, without additives or organic solvents. Results revealed that a solid state reaction inside the ZnO/SiO2 nanocomposites occurs with increasing the annealing temperature. The reaction of ZnO NPs with SiO2 matrix was insignificant up to approximately 500 degrees C. However, ZnO NPs react strongly with the silica matrix when the nanocomposites are annealed at temperatures above 700 degrees C. Extensive annealing of the ZnO/SiO2 nanocomposite at 900 degrees C yields 3D structures made of 500 nm rod-like, 5-7 pm tube-like and 35 pm needle-like Zn2SiO4 crystals. A possible mechanism for forming ZnO NPs inside porous silica matrix and phase transformation of the ZnO/SiO2 nanocomposites into 3D architectures of Zn2SiO4 are carefully discussed. (C) 2017 Elsevier Ltd. All rights reserved. |
| 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 |
000397360000030 |
Publication Date |
2017-01-23 |
| Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0264-1275 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.364 |
Times cited |
43 |
Open Access |
Not_Open_Access |
| Notes |
; A.B. would like to thank FWO – Research Foundation Flanders (grant no. V450315N) and the Strategic Initiative Materials in Flanders (SBO-project no. 130529 – INSITU) for financial support. TEM and TEM-EDX analyses were performed by Dr. F. Leroux (EMAT, Universiteit Antwerpen). XRD and DSC measurements were performed by T. Segato (4MAT, Universite Libre de Bruxelles). Notes: the authors declare no competing for financial interest. ; |
Approved |
Most recent IF: 4.364 |
| Call Number |
UA @ lucian @ c:irua:142394UA @ admin @ c:irua:142394 |
Serial |
4689 |
| Permanent link to this record |
