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Author |
Naberezhnyi, D.; Rumyantseva, M.; Filatova, D.; Batuk, M.; Hadermann, J.; Baranchikov, A.; Khmelevsky, N.; Aksenenko, A.; Konstantinova, E.; Gaskov, A. |
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Title |
Effects of Ag additive in low temperature CO detection with In2O3 based gas sensors |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Nanomaterials |
Abbreviated Journal |
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Volume |
8 |
Issue |
10 |
Pages |
801 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Nanocomposites In2O3/Ag obtained by ultraviolet (UV) photoreduction and impregnation methods were studied as materials for CO sensors operating in the temperature range 25-250 degrees C. Nanocrystalline In2O3 and In2O3/Ag nanocomposites were characterized by X-ray diffraction (XRD), single-point Brunauer-Emmet-Teller (BET) method, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) with energy dispersive X-ray (EDX) mapping. The active surface sites were investigated using Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR) spectroscopy and thermo-programmed reduction with hydrogen (TPR-H-2) method. Sensor measurements in the presence of 15 ppm CO demonstrated that UV treatment leads to a complete loss of In2O3 sensor sensitivity, while In2O3/Ag-UV nanocomposite synthesized by UV photoreduction demonstrates an increased sensor signal to CO at T < 200 degrees C. The observed high sensor response of the In2O3/Ag-UV nanocomposite at room temperature may be due to the realization of an additional mechanism of CO oxidation with participation of surface hydroxyl groups associated via hydrogen bonds. |
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Wos |
000451174100057 |
Publication Date |
2018-10-08 |
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Series Issue |
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Edition |
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ISSN  |
2079-4991 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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no |
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Call Number |
UA @ admin @ c:irua:156335 |
Serial |
7842 |
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Author |
Bagherpour, A.; Baral, P.; Colla, M.-S.; Orekhov, A.; Idrissi, H.; Haye, E.; Pardoen, T.; Lucas, S. |
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Title |
Tailoring Mechanical Properties of a-C:H:Cr Coatings |
Type |
A1 Journal Article |
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Year |
2023 |
Publication |
Coatings |
Abbreviated Journal |
Coatings |
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Volume |
13 |
Issue |
12 |
Pages |
2084 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
The development of coatings with tunable performances is critical to meet a wide range of technological applications each one with different requirements. Using the plasma-enhanced chemical vapor deposition (PECVD) process, scientists can create hydrogenated amorphous carbon coatings doped with metal (a-C:H:Me) with a broad range of mechanical properties, varying from those resembling polymers to ones resembling diamond. These diverse properties, without clear relations between the different families, make the material selection and optimization difficult but also very rich. An innovative approach is proposed here based on projected performance indices related to fracture energy, strength, and stiffness in order to classify and optimize a-C:H:Me coatings. Four different a-C:H:Cr coatings deposited by PECVD with Ar/C2H2 discharge under different bias voltage and pressures are investigated. A path is found to produce coatings with a selective critical energy release rate between 5–125 J/m2 without compromising yield strength (1.6–2.7 GPa) and elastic limit (≈0.05). Finally, fine-tuned coatings are categorized to meet desired applications under different testing conditions. |
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Wos |
001136013600001 |
Publication Date |
2023-12-14 |
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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 |
2079-6412 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
Walloon region under the PDR FNRS, C 62/5—PDR/OL 33677636 ; Belgian National Fund for Scientific Research, CDR—J.0113.20 ; National Fund for Scientific Reaserch; |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @c:irua:202390 |
Serial |
8982 |
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Author |
Yu, W.-B.; Hu, Z.-Y.; Jin, J.; Yi, M.; Yan, M.; Li, Y.; Wang, H.-E.; Gao, H.-X.; Mai, L.-Q.; Hasan, T.; Xu, B.-X.; Peng, D.-L.; Van Tendeloo, G.; Su, B.-L. |
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Title |
Unprecedented and highly stable lithium storage capacity of (001) faceted nanosheet-constructed hierarchically porous TiO₂/rGO hybrid architecture for high-performance Li-ion batteries |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
National Science Review |
Abbreviated Journal |
Natl Sci Rev |
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Volume |
7 |
Issue |
6 |
Pages |
1046-1058 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Active crystal facets can generate special properties for various applications. Herein, we report a (001) faceted nanosheet-constructed hierarchically porous TiO2/rGO hybrid architecture with unprecedented and highly stable lithium storage performance. Density functional theory calculations show that the (001) faceted TiO2 nanosheets enable enhanced reaction kinetics by reinforcing their contact with the electrolyte and shortening the path length of Li+ diffusion and insertion-extraction. The reduced graphene oxide (rGO) nanosheets in this TiO2/rGO hybrid largely improve charge transport, while the porous hierarchy at different length scales favors continuous electrolyte permeation and accommodates volume change. This hierarchically porous TiO2/rGO hybrid anode material demonstrates an excellent reversible capacity of 250 mAh g(-1) at 1 C (1 C = 335 mA g(-1)) at a voltage window of 1.0-3.0 V. Even after 1000 cycles at 5 C and 500 cycles at 10 C, the anode retains exceptional and stable capacities of 176 and 160 mAh g(-1), respectively. Moreover, the formed Li2Ti2O4 nanodots facilitate reversed Li+ insertion-extraction during the cycling process. The above results indicate the best performance of TiO2-based materials as anodes for lithium-ion batteries reported in the literature. |
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Wos |
000544175300013 |
Publication Date |
2020-02-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2095-5138 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
20.6 |
Times cited |
3 |
Open Access |
OpenAccess |
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Notes |
; This work was supported by the National Key R&D Program of China (2016YFA0202602 and 2016YFA0202603), the National Natural Science Foundation of China (U1663225) and Program for Changjiang Scholars and Innovative Research Team in University (IRT_15R52). ; |
Approved |
Most recent IF: 20.6; 2020 IF: 8.843 |
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Call Number |
UA @ admin @ c:irua:170776 |
Serial |
6648 |
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Author |
Wang, L.; Li, Y.; Yang, X.-Y.; Zhang, B.-B.; Ninane, N.; Busscher, H.J.; Hu, Z.-Y.; Delneuville, C.; Jiang, N.; Xie, H.; Van Tendeloo, G.; Hasan, T.; Su, B.-L. |
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Title |
Single-cell yolk-shell nanoencapsulation for long-term viability with size-dependent permeability and molecular recognition |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
National Science Review |
Abbreviated Journal |
Natl Sci Rev |
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Volume |
8 |
Issue |
4 |
Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Like nanomaterials, bacteria have been unknowingly used for centuries. They hold significant economic potential for fuel and medicinal compound production. Their full exploitation, however, is impeded by low biological activity and stability in industrial reactors. Though cellular encapsulation addresses these limitations, cell survival is usually compromised due to shell-to-cell contacts and low permeability. Here, we report ordered packing of silica nanocolloids with organized, uniform and tunable nanoporosities for single cyanobacterium nanoencapsulation using protamine as an electrostatic template. A space between the capsule shell and the cell is created by controlled internalization of protamine, resulting in a highly ordered porous shell-void-cell structure formation. These unique yolk-shell nano structures provide long-term cell viability with superior photosynthetic activities and resistance in harsh environments. In addition, engineering the colloidal packing allows tunable shell-pore diameter for size-dependent permeability and introduction of new functionalities for specific molecular recognition. Our strategy could significantly enhance the activity and stability of cyanobacteria for various nanobiotechnological applications. |
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Wos |
000651827200002 |
Publication Date |
2020-05-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2095-5138 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.843 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 8.843 |
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Call Number |
UA @ admin @ c:irua:179085 |
Serial |
6885 |
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Author |
Meng, X.; Chen, S.; Peng, H.; Bai, H.; Zhang, S.; Su, X.; Tan, G.; Van Tendeloo, G.; Sun, Z.; Zhang, Q.; Tang, X.; Wu, J. |
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Title |
Ferroelectric engineering : enhanced thermoelectric performance by local structural heterogeneity |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Science China : materials |
Abbreviated Journal |
Sci China Mater |
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Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Although traditional ferroelectric materials are usually dielectric and nonconductive, GeTe is a typical ferroelectric semiconductor, possessing both ferroelectric and semiconducting properties. GeTe is also a widely studied thermoelectric material, whose performance has been optimized by doping with various elements. However, the impact of the ferroelectric domains on the thermoelectric properties remains unclear due to the difficulty to directly observe the ferroelectric domains and their evolutions under actual working conditions where the material is exposed to high temperatures and electric currents. Herein, based on in-situ investigations of the ferroelectric domains and domain walls in both pure and Sb-doped GeTe crystals, we have been able to analyze the dynamic evolution of the ferroelectric domains and domain walls, exposed to an electric field and temperature. Local structural heterogeneities and nano-sized ferroelectric domains are generated due to the interplay of the Sb3+ dopant and the Ge-vacancies, leading to the increased number of charged domain walls and a much improved thermoelectric performance. This work reveals the fundamental mechanism of ferroelectric thermoelectrics and provides insights into the decoupling of previously interdependent properties such as thermo-power and electrical conductivity. |
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Wos |
000749973500001 |
Publication Date |
2022-02-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2095-8226; 2199-4501 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.1 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 8.1 |
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Call Number |
UA @ admin @ c:irua:186429 |
Serial |
6959 |
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Author |
Geboes, B.; Ustarroz, J.; Sentosun, K.; Vanrompay, H.; Hubin, A.; Bals, S.; Breugelmans, T. |
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Title |
Electrochemical behavior of electrodeposited nanoporous Pt catalysts for the oxygen reduction reaction |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
6 |
Issue |
6 |
Pages |
5856-5864 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
Nanoporous Pt based nanoparticles (NP's) are promising fuel cell catalysts due to their high surface area and increased electrocatalytic activity toward the ORR In this work a direct double-pulse electrodeposition procedure at room temperature is applied to obtain dendritic Pt structures (89 nm diameter) with a high level of porosity (ca. 25%) and nanopores of 2 nm protruding until the center of the NP's. The particle morphology is characterized using aberration corrected high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and electron tomography (ET) combined with field emission scanning electron microscopy (FESEM) and macroscopic electrochemical measurements to assess their activity and stability toward the ORR. Macroscopic determination of the active surface area through hydrogen UPD measurements in combination with FESEM and ET showed that a considerable amount of the active sites inside the pores of the low overpotential NP's were accessible to oxygen species. As a result of this accessibility, up to a 9-fold enhancement of the Pt mass corrected ORR activity at 0.85 V vs RHE was observed at the highly porous structures. After successive potential cycling upward to 1.5 V vs RHE in a deaerated HClO4 solution a negative shift of 71 mV in half-wave potential occurred. This decrease in ORR activity could be correlated to the partial collapse of the nanopores, visible in both the EASA values and 3D ET reconstructions. |
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Wos |
000382714000025 |
Publication Date |
2016-07-18 |
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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 |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
48 |
Open Access |
OpenAccess |
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Notes |
; The Quanta 250 FEG microscope of the Electron Microscopy for Material Science group at the University of Antwerp was funded by the Hercules foundation of the Flemish Government. The authors acknowledge financial support from the Fonds Wetenschappelijk Onderzoek in Flanders (FWOAL708). S.B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). J.U. acknowledges funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, postdoctoral grant 12I7816N). ; ecas_Sara |
Approved |
Most recent IF: 10.614 |
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Call Number |
UA @ lucian @ c:irua:135703 |
Serial |
4302 |
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Author |
Verduyckt, J.; Van Hoof, M.; De Schouwer, F.; Wolberg, M.; Kurttepeli, M.; Eloy, P.; Gaigneaux, E.M.; Bals, S.; Kirschhock, C.E.A.; De Vos, D.E. |
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Title |
PdPb-catalyzed decarboxylation of proline to pyrrolidine : highly selective formation of a biobased amine in water |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
6 |
Issue |
6 |
Pages |
7303-7310 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Amino acids have huge potential as platform chemicals in the biobased industry. Pd-catalyzed decarboxylation is a very promising route for the valorization of these natural compounds derived from protein waste or fermentation. We report that the highly abundant and nonessential amino acid L-proline is very reactive in the Pd-catalyzed decarboxylation. Full conversions are obtained with Pd/C and different Pd/MeOx catalysts; this allowed the identification of the different side reactions and the mapping of the reaction network. Due to the high reactivity of pyrrolidine, the selectivity for pyrrolidine was initially low. By carefully modifying Pd/ZrO2 with Pb in a controlled manner-via two incipient wetness impregnation steps-the selectivity increased remarkably. Finally, a thorough investigation of the reaction parameters resulted in an increased activity of this modified catalyst and an even further enhanced selectivity under a low H-2 pressure of 4 bar at 235 degrees C in water. This results in a very selective and sustainable production route for the highly interesting pyrrolidine. |
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Wos |
000387306100005 |
Publication Date |
2016-09-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
27 |
Open Access |
OpenAccess |
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Notes |
; J.V. and F.D.S. thank Fonds Wetenschappelijk Onderzoek (FWO) and Agency for Innovation by Science and Technology (IWT) for doctoral fellowships. D.D.V. acknowledges IWT and FWO for research project funding. D.D.V. and C.E.A.K. acknowledge the Flemish government for long-term structural funding through Methusalem. D.D.V. and S.B. acknowledge Belspo (IAP-PAI 7/05) for financial support. S.B. is grateful for funding by the European Research Council (ERC starting grant no. 335078-COLOURATOMS). The authors also thank the Department of Chemistry, University of Cologne, Germany for use of their XRD equipment. Finally, the assistance of Karel Duerinckx, Werner Wouters, Walter Vermandel, Ivo Stassen, Dries Jonckheere, Sabina Accardo and Bart Bueken with 11-1 NMR, pressure reactors, CO chemisorption, N<INF>2</INF> physisorption, SEM, gas phase FTIR and high-throughput XRD, respectively, is very much appreciated. ; ecas_Sara |
Approved |
Most recent IF: 10.614 |
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Call Number |
UA @ lucian @ c:irua:139171 |
Serial |
4445 |
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Author |
Theofanidis, S.A.; Galvita, V.V.; Poelman, H.; Dharanipragada, N.V.R.A.; Longo, A.; Meledina, M.; Van Tendeloo, G.; Detavernier, C.; Marin, G.B. |
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Title |
Fe-containing magnesium aluminate support for stability and carbon control during methane reforming |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
8 |
Issue |
7 |
Pages |
5983-5995 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a MgFexAl2-xO4 synthetic spinel, where x varies from 0 to 0.26, as support for Ni-based catalysts, offering stability and carbon control under various conditions of methane reforming. By incorporation of Fe into a magnesium aluminate spine!, a support is created with redox functionality and high thermal stability, as concluded from temporal analysis of products (TAP) experiments and redox cycling, respectively. A diffusion coefficient of 3 x 10(-17) m(2) s(-1) was estimated for lattice oxygen at 993 K from TAP experiments. X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) modeling identified that the incorporation of iron occurs as Fe3+ in the octahedral sites of the spinel lattice, replacing aluminum. Simulation of the X-ray absorption near edge structure (XANES) spectrum of the reduced support showed that 60 +/- 10% of iron was reduced from 3+ to 2+ at 1073 K, while there was no formation of metallic iron. A series of Ni/MgFexAl2-xO4 catalysts, where x varies from 0 to 0.26, was synthesized and reduced, yielding a supported Ni-Fe alloy. The evolution of the catalyst structure during H-2 temperature-programmed reduction (TPR) and CO2 temperature-programmed oxidation (TPO) was examined using time-resolved in situ XRD and XANES. During reforming, iron in both the support and alloy keeps control of carbon accumulation, as confirmed by O-2-TPO on the spent catalysts. By fine tuning the amount of Fe in MgFexAl2-xO4, a supported alloy was obtained with a Ni/Fe molar ratio of similar to 10, which was active for reforming and stable. By comparison of the performance of Ni-based catalysts with Fe either incorporated into or deposited onto the support, the location of Fe within the support proved crucial for the stability and carbon mitigation under reforming conditions. |
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Publisher |
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Place of Publication |
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Editor |
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Wos |
000438475100034 |
Publication Date |
2018-05-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
18 |
Open Access |
OpenAccess |
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Notes |
; This work was supported by the FAST industrialization by Catalyst Research and Development (FASTCARD) project, which is a Large Scale Collaborative Project supported by the European Commission in the 7th Framework Programme (GA no 604277), the “Long Term Structural Methusalem Funding by the Flemish Government”, the Interuniversity Attraction Poles Programme, IAP7/5, Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of travel costs and beam time at the DUBBLE beamline of the ESRF. The authors acknowledge the assistance from the DUBBLE (ESRF, XAS campaign 26-01-1048) and ROCK staff (SOLEIL, proposal 201502561). The authors equally acknowledge support from a public grant overseen by the French National Research Agency (ANR) as part of the “Investissements d'Avenir” program (reference: ANR-10-EQPX-45) for the ROCK beamline and from Lukas Buelens and Rakesh Batchu (Laboratory for Chemical Technology, Ghent University) for the STEM measurements and TAP experiments, respectively. ; |
Approved |
Most recent IF: 10.614 |
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Call Number |
UA @ lucian @ c:irua:153178 |
Serial |
5102 |
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Author |
Tang, Z.; Liu, P.; Cao, H.; Bals, S.; Heeres, H.J.; Pescarmona, P.P. |
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Title |
Pr/ZrO2 prepared by atomic trapping : an efficient catalyst for the conversion of glycerol to lactic acid with concomitant transfer hydrogenation of cyclohexene |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
9 |
Issue |
9 |
Pages |
9953-9963 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A series of heterogeneous catalysts consisting of highly dispersed Pt nanoparticles supported on nanosized ZrO2 (20 to 60 nm) was synthesized and investigated for the one-pot transfer hydrogenation between glycerol and cyclohexene to produce lactic acid and cyclohexane, without any additional H-2. Different preparation methods were screened, by varying the calcination and reduction procedures with the purpose of optimizing the dispersion of Pt species (i.e., as single-atom sites or extra-fine Pt nanoparticles) on the ZrO2 support. The Pt/ZrO2 catalysts were characterized by means of transmission electron microscopy techniques (HAADF-STEM, TEM), elemental analysis (ICP-OES, EDX mapping), N-2-physisorption, H-2 temperature-programmed-reduction (H-2-TPR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Based on this combination of techniques it was possible to correlate the temperature of the calcination and reduction treatments with the nature of the Pt species. The best catalyst consisted of subnanometer Pt clusters (<1 nm) and atomically dispersed Pt (as Pt2+ and Pt4+) on the ZrO2 support, which were converted into extra-fine Pt nanoparticles (average size = 1.4 nm) upon reduction. These nanoparticles acted as catalytic species for the transfer hydrogenation of glycerol with cyclohexene, which gave an unsurpassed 95% yield of lactic acid salt at 96% glycerol conversion (aqueous glycerol solution, NaOH as promoter, 160 degrees C, 4.5 h, at 20 bar N-2). This is the highest yield and selectivity of lactic acid (salt) reported in the literature so far. Reusability experiments showed a partial and gradual loss of activity of the Pt/ZrO2 catalyst, which was attributed to the experimentally observed aggregation of Pt nanoparticles. |
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Wos |
000494549700025 |
Publication Date |
2019-09-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
10.614 |
Times cited |
46 |
Open Access |
OpenAccess |
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| |
Notes |
Zhenchen Tang acknowledges the financial support from the China Scholarship Council for his Ph.D. grant. All the authors are grateful for the technical support from Erwin Wilbers, Anne Appeldoorn, and Marcel de Vries, the TEM support from Dr. Marc Stuart, and the ICP-OES support from Johannes van der Velde. Pei Liu and Sara Bals acknowledge financial support from the European Commission under the Horizon 2020 Programme by means of grant agreement No. 731019 EUSMI. |
Approved |
Most recent IF: 10.614 |
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| |
Call Number |
UA @ admin @ c:irua:164643 |
Serial |
6326 |
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| Permanent link to this record |
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Author |
Saveleva, V.A.; Wang, L.; Kasian, O.; Batuk, M.; Hadermann, J.; Gallet, J.-j.; Bournel, F.; Alonso-Vante, N.; Ozouf, G.; Beauger, C.; Mayrhofer, K.J.J.; Cherevko, S.; Gago, A.S.; Friedrich, K.A.; Zafeiratos, S.; Savinova, E.R. |
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Title |
Insight into the Mechanisms of High Activity and Stability of Iridium Supported on Antimony-Doped Tin Oxide Aerogel for Anodes of Proton Exchange Membrane Water Electrolyzers |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
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| |
Volume |
10 |
Issue |
4 |
Pages |
2508-2516 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The use of high amounts of iridium in industrial proton exchange membrane water electrolysers (PEMWE) could hinder their widespread use for the decarbonisation of society with hydrogen. Non-thermally oxidised Ir nanoparticles supported on antimony-doped tin oxide (SnO2:Sb, ATO) aerogel allow decreasing the use of the precious metal by more than 70 %, while enhancing the electro-catalytic activity and stability. To date the origin of these benefits remains unknown. Here we present clear evidence on the mechanisms that lead to the enhancement of the electrochemical properties of the catalyst. Operando near ambient pressure X-ray photoelectron spectroscopy on membrane electrode assemblies reveals a low degree of Ir oxidation, attributed to the oxygen spill-over from Ir to SnO2:Sb. Furthermore, the formation of highly unstable Ir(III) species is mitigated, while the decrease of Ir dissolution in Ir/SnO2:Sb is confirmed by inductively coupled plasma mass spectrometry (ICP-MS). The mechanisms that lead to the high activity and stability of Ir catalyst supported on SnO2:Sb aerogel for PEMWE are thus unveiled. |
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Place of Publication |
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Wos |
000516887400011 |
Publication Date |
2020-02-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.9 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
The research leading to these results has received funding from the European Union’s Seventh Framework Program (FP7/2007-2013) for Fuel Cell and Hydrogen Joint Technology (FCH JU) Initiative under Grant No. 621237 (INSIDE). In addition, A.S.G. and C.B. thank the European Union’s Horizon 2020 research and innovation programme for funding the project PRETZEL under grant agreement No 779478 and it is supported by FCH JU. Solvay is acknowledged for providing Aquivion membrane and ionomer. |
Approved |
Most recent IF: 12.9; 2020 IF: 10.614 |
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Call Number |
EMAT @ emat @c:irua:167147 |
Serial |
6341 |
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| Permanent link to this record |
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Author |
Irtem, E.; Arenas Esteban, D.; Duarte, M.; Choukroun, D.; Lee, S.; Ibáñez, M.; Bals, S.; Breugelmans, T. |
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Title |
Ligand-Mode Directed Selectivity in Cu–Ag Core–Shell Based Gas Diffusion Electrodes for CO2Electroreduction |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
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Issue |
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Pages |
13468-13478 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
Bimetallic nanoparticles with tailored size and specific composition have shown promise as stable and selective catalysts for electrochemical reduction of CO2 (CO2R) in batch systems. Yet, limited effort was devoted to understand the effect of ligand coverage and postsynthesis treatments on CO2 reduction, especially under industrially applicable conditions, such as at high currents (>100 mA/cm2) using gas diffusion electrodes (GDE) and flow reactors. In this work, Cu–Ag core–shell nanoparticles (11 ± 2 nm) were prepared with three different surface modes: (i) capped with oleylamine, (ii) capped with monoisopropylamine, and (iii) surfactant free with a reducing borohydride agent; Cu–Ag (OAm), Cu–Ag (MIPA), and Cu–Ag (NaBH4), respectively. The ligand exchange and removal was evidenced by infrared spectroscopy (ATR-FTIR) analysis, whereas high-resolution scanning transmission electron microscopy (HAADF-STEM) showed their effect on the interparticle distance and nanoparticle rearrangement. Later on, we developed a process-on-substrate method to track these effects on CO2R. Cu–Ag (OAm) gave a lower on-set potential for hydrocarbon production, whereas Cu–Ag (MIPA) and Cu–Ag (NaBH4) promoted syngas production. The electrochemical impedance and surface area analysis on the well-controlled electrodes showed gradual increases in the electrical conductivity and active surface area after each surface treatment. We found that the increasing amount of the triple phase boundaries (the meeting point for the electron–electrolyte–CO2 reactant) affect the required electrode potential and eventually the C+2e̅/C2e̅ product ratio. This study highlights the importance of the electron transfer to those active sites affected by the capping agents—particularly on larger substrates that are crucial for their industrial application. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000592978900031 |
Publication Date |
2020-11-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.9 |
Times cited |
23 |
Open Access |
OpenAccess |
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Notes |
The authors also acknowledge financial support from the University Research Fund (BOF-GOA-PS ID No. 33928). S.L. has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie SkłodowskaCurie Grant Agreement No. 665385. |
Approved |
Most recent IF: 12.9; 2020 IF: 10.614 |
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Call Number |
EMAT @ emat @c:irua:173803 |
Serial |
6432 |
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| Permanent link to this record |
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Author |
Van Velthoven, N.; Henrion, M.; Dallenes, J.; Krajnc, A.; Bugaev, A.L.; Liu, P.; Bals, S.; Soldatov, A.; Mali, G.; De Vos, D.E. |
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Title |
S,O-functionalized metal-organic frameworks as heterogeneous single-site catalysts for the oxidative alkenylation of arenes via C- H activation |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
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| |
Volume |
10 |
Issue |
9 |
Pages |
5077-5085 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Heterogeneous single-site catalysts can combine the R precise active site design of organometallic complexes with the efficient recovery of solid catalysts. Based on recent progress on homogeneous thioether ligands for Pd-catalyzed C-H activation reactions, we here develop a scalable metal-organic framework-based heterogeneous single-site catalyst containing S,O-moieties that increase the catalytic activity of Pd(II) for the oxidative alkenylation of arenes. The structure of the Pd@MOF-808-L1 catalyst was characterized in detail via solid-state nuclear magnetic resonance spectroscopy, N-2 physisorption, and high-angle annular dark field scanning transmission electron microscopy, and the structure of the isolated palladium active sites could be identified by X-ray absorption spectroscopy. A turnover frequency (TOF) of 8.4 h(-1) was reached after 1 h of reaction time, which was 3 times higher than the TOF of standard Pd(OAc)(2), ranking Pd@MOF-808-L1 among the most active heterogeneous catalysts ever reported for the nondirected oxidative alkenylation of arenes. Finally, we showed that the single-site catalyst promotes the oxidative alkenylation of a broad range of electron-rich arenes, and the applicability of this heterogeneous system was demonstrated by the gram-scale synthesis of industrially relevant products. |
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Wos |
000530090800026 |
Publication Date |
2020-04-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.9 |
Times cited |
37 |
Open Access |
OpenAccess |
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Notes |
; The research leading to these results has received funding from the NMBP-01-2016 Program of the European Union's Horizon 2020 Framework Program H2020/2014-2020/under grant agreement no [720996]. N.V.V. and D.E.D.V. thank the FWO for funding (1S32917N and G0F2320N). D.E.D.V. is grateful for KU Leuven's support in the frame of the CASAS Metusalem project and a C3 type project. A.K. and G.M. acknowledge the financial support from the Slovenian Research Agency (research core funding no. P1-0021 and project no. N1-0079). A.L.B and A.V.S. acknowledge Russian Science Foundation grant no. 20-43-01015 for financial support. We thank Alexander Trigub and Alexey Veligzhanin for their support during the beamtime at Kurchatov Institute. We are indebted to Elizaveta Kamyshova and Anna Pnevskaya for their valuable help during EXAFS measurements. P.L. and S.B. thank European Research Council for the ERC Consolidator Grant 815128, REALNANO. Kassem Amro and Guillaume Gracy from Sikemia are gratefully acknowledged for providing ; sygma |
Approved |
Most recent IF: 12.9; 2020 IF: 10.614 |
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Call Number |
UA @ admin @ c:irua:169530 |
Serial |
6598 |
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Author |
Coeck, R.; Meeprasert, J.; Li, G.; Altantzis, T.; Bals, S.; Pidko, E.A.; De Vos, D.E. |
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Title |
Gold and silver-catalyzed reductive amination of aromatic carboxylic acids to benzylic amines |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
11 |
Issue |
13 |
Pages |
7672-7684 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
The reductive amination of benzoic acid and its derivatives would be an effective addition to current synthesis methods for benzylamine. However, with current technology it is very difficult to keep the aromaticity intact when starting from benzoic acid, and salt wastes are often generated in the process. Here, we report a heterogeneous catalytic system for such a reductive amination, requiring solely H-2 and NH3 as the reactants. The Ag/TiO2 or Au/TiO2 catalysts can be used multiple times, and very little noble metal is required, only 0.025 mol % Au. The catalysts are bifunctional: the support catalyzes the dehydration of both the ammonium carboxylate to the amide and of the amide to the nitrile, while the sites at the metal-support interface promote the hydrogenation of the in situ generated nitrile. Yields of up to 92% benzylamine were obtained. |
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Language |
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Wos |
000670659900005 |
Publication Date |
2021-06-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
16 |
Open Access |
OpenAccess |
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Notes |
R.C. thanks the FWO for his SB PhD fellowship. D.E.D.V. acknowledges FWO for research project funding, as well as KU Leuven for funding in the Metusalem program Casas. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO). T.A. acknowledges funding from the University of Antwerp Research fund (BOF). E.A.P. acknowledges the support from the European Research Council (ERC Consolidator grant #725686 DeliCAT). J.M. acknowledges financial support through the Royal Thai Government Scholarship. DFT calculations on SURFsara supercomputer facilities were performed with support from the Netherlands Organization for Scientific Research (NWO).; sygmaSB |
Approved |
Most recent IF: 10.614 |
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Call Number |
UA @ admin @ c:irua:179851 |
Serial |
6840 |
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Author |
Nematollahi, P.; Barbiellini, B.; Bansil, A.; Lamoen, D.; Qingying, J.; Mukerjee, S.; Neyts, E.C. |
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Title |
Identification of a Robust and Durable FeN4CxCatalyst for ORR in PEM Fuel Cells and the Role of the Fifth Ligand |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
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Issue |
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Pages |
7541-7549 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Although recent studies have advanced the understanding of pyrolyzed
Fe−N−C materials as oxygen reduction reaction (ORR) catalysts, the atomic and
electronic structures of the active sites and their detailed reaction mechanisms still remain unknown. Here, based on first-principles density functional theory (DFT) computations, we discuss the electronic structures of three FeN4 catalytic centers with different local topologies of the surrounding C atoms with a focus on unraveling the mechanism of their ORR activity in acidic electrolytes. Our study brings back a forgotten, synthesized pyridinic Fe−N coordinate to the community’s attention, demonstrating that this catalyst can exhibit excellent activity for promoting direct four-electron ORR through the addition of a fifth ligand such as −NH2, −OH, and −SO4. We also identify sites with good stability properties through the combined use of our DFT calculations and Mössbauer spectroscopy data. |
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Corporate Author |
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Place of Publication |
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Wos |
000823193100001 |
Publication Date |
2022-06-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS full record; WoS citing articles |
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Impact Factor |
12.9 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Basic Energy Sciences, DE-FG02-07ER46352 ; Fonds Wetenschappelijk Onderzoek, 1261721N ; Opetus- ja Kulttuuriministeri?; Department of Energy, DE-EE0008416 ; |
Approved |
Most recent IF: 12.9 |
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Call Number |
EMAT @ emat @c:irua:189000 |
Serial |
7073 |
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Author |
Yang, S.; Liu, Z.; An, H.; Arnouts, S.; de Ruiter, J.; Rollier, F.; Bals, S.; Altantzis, T.; Figueiredo, M.C.; Filot, I.A.W.; Hensen, E.J.M.; Weckhuysen, B.M.; van der Stam, W. |
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Title |
Near-unity electrochemical CO₂ to CO conversion over Sn-doped copper oxide nanoparticles |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
12 |
Issue |
24 |
Pages |
15146-15156 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
Bimetallic electrocatalysts have emerged as a viable strategy to tune the electrocatalytic CO2 reduction reaction (eCO2RR) for the selective production of valuable base chemicals and fuels. However, obtaining high product selectivity and catalyst stability remain challenging, which hinders the practical application of eCO2RR. In this work, it was found that a small doping concentration of tin (Sn) in copper oxide (CuO) has profound influence on the catalytic performance, boosting the Faradaic efficiency (FE) up to 98% for carbon monoxide (CO) at -0.75 V versus RHE, with prolonged stable performance (FE > 90%) for up to 15 h. Through a combination of ex situ and in situ characterization techniques, the in situ activation and reaction mechanism of the electrocatalyst at work was elucidated. In situ Raman spectroscopy measurements revealed that the binding energy of the crucial adsorbed *CO intermediate was lowered through Sn doping, thereby favoring gaseous CO desorption. This observation was confirmed by density functional theory, which further indicated that hydrogen adsorption and subsequent hydrogen evolution were hampered on the Sn-doped electrocatalysts, resulting in boosted CO formation. It was found that the pristine electrocatalysts consisted of CuO nanoparticles decorated with SnO2 domains, as characterized by ex situ high-resolution scanning transmission electron microscopy and X-ray photoelectron spectroscopy measurements. These pristine nanoparticles were subsequently in situ converted into a catalytically active bimetallic Sn-doped Cu phase. Our work sheds light on the intimate relationship between the bimetallic structure and catalytic behavior, resulting in stable and selective oxide-derived Sn-doped Cu electrocatalysts. |
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Wos |
000900052400001 |
Publication Date |
2022-11-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.9 |
Times cited |
16 |
Open Access |
OpenAccess |
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Notes |
B.M.W., S.Y., M.C.F., E.J.M.H., and W.v.d.S. acknowledge support from the Strategic UU-TU/e Alliance project ?Joint Centre for Chemergy Research?. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO) . Z.L. acknowledges financial support of the China Scholarship Council and the Netherlands Organization for Scientific Research for access to computa-tional resources for carrying out the DFT calculations reported in this work. S.A. and T.A. acknowledge funding from theUniversity of Antwerp Research fund (BOF) . The authors also thank Dr. Jochem Wijten and Joris Janssens (Inorganic Chemistry and Catalysis, Utrecht University) for helpful technical support. Sander Deelen (Faculty of Science, Utrecht University) is acknowledged for the design of the in situ XRD cell. |
Approved |
Most recent IF: 12.9 |
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Call Number |
UA @ admin @ c:irua:192742 |
Serial |
7325 |
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Author |
Ennaert, T.; Geboers, J.; Gobechiya, E.; Courtin, C.M.; Kurttepeli, M.; Houthoofd, K.; Kirschhock, C.E.A.; Magusin, P.C.M.M.; Bals, S.; Jacobs, P.A.; Sels, B.F. |
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Title |
Conceptual frame rationalizing the self-stabilization of H-USY zeolites in hot liquid water |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
5 |
Issue |
5 |
Pages |
754-768 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The wide range of liquid-phase reactions required for the catalytic conversion of biomass compounds into new bioplatform molecules defines a new set of challenges for the development of active, selective, and stable catalysts. The potential of bifunctional Ru/H-USY catalysts for conversions in hot liquid water (HLW) is assessed in terms of physicochemical stability and long-term catalytic performance of acid sites and noble metal functionality, as probed by hydrolytic hydrogenation of cellulose. It is shown that zeolite desilication is the main zeolite degradation mechanism in HLW. USY zeolite stability depends on two main parameters, viz., framework and extra-framework aluminum content. The former protects the zeolite lattice by counteracting hydrolysis of framework bonds, and the latter, when located at the external crystal surface, prevents solubilization of the zeolite framework which is the result of its low water-solubility. Hence, the hot liquid water stability of commercial H-USY zeolites, in contrast to their steam stability, increased with decreasing Si/AI ratio. As a result, mildly steamed USY zeolites containing a high amount of both Al species exhibit the highest resistance to HLW. During an initial period of transformations, Al-rich zeolites form additional protective extra-framework Al species at the outer surface, self-stabilizing the framework. A critical bulk Si/AI ratio of 3 was determined whereby USY zeolites with a lower Si/AI ratio will self-stabilize over time. Besides, due to the initial transformation period, the accessibility of the catalytic active sites is extensively enhanced resulting in a material that is more stable and drastically more accessible to large substrates than the original zeolite. When these findings are applied in the hydrolytic hydrogenation of cellulose, unprecedented nearly quantitative hexitol yields were obtained with a stable catalytic system. |
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Place of Publication |
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Wos |
000349275300031 |
Publication Date |
2014-12-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435;2155-5435; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
65 |
Open Access |
OpenAccess |
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Notes |
335078 Colouratom; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 10.614; 2015 IF: 9.312 |
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Call Number |
c:irua:125288 |
Serial |
474 |
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Author |
Mei, B.; Wiktor, C.; Turner, S.; Pougin, A.; Van Tendeloo, G.; Fischer, R.A.; Muhler, M.; Strunk, J. |
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Title |
Evidence for metalsupport interactions in Au modified TiOx/SBA-15 materials prepared by photodeposition |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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| |
Volume |
3 |
Issue |
12 |
Pages |
3041-3049 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Gold nanoparticles have been efficiently photodeposited onto titanate-loaded SBA-15 (Ti(x)/SBA-15) with different titania coordination. Transmission electron microscopy shows that relatively large Au nanoparticles are photodeposited on the outer surface of the Ti(x)/SBA-15 materials and that TiOx tends to form agglomerates in close proximity to the Au nanoparticles, often forming coreshell Au/TiOx structures. This behavior resembles typical processes observed due to strong-metal support interactions. In the presence of gold, the formation of hydrogen on Ti(x)/SBA-15 during the photodeposition process and the performance in the hydroxylation of terephthalic acid is greatly enhanced. The activity of the Au/Ti(x)/SBA-15 materials is found to depend on the TiOx loading, increasing with a larger amount of initially isolated TiO4 tetrahedra. Samples with initially clustered TiOx species show lower photocatalytic activities. When isolated zinc oxide (ZnOx) species are present on Ti(x)/SBA-15, gold nanoparticles are smaller and well dispersed within the pores. Agglomeration of TiOx species and the formation of Au/TiOx structures is negligible. The dispersion of gold and the formation of Au/TiOx in the SBA-15 matrix seem to depend on the mobility of the TiOx species. The mobility is determined by the initial degree of agglomeration of TiOx. Effective hydrogen evolution requires Au/TiOx coreshell composites as in Au/Ti(x)/SBA-15, whereas hydroxylation of terephthalic acid can also be performed with Au/ZnOx/TiOx/SBA-15 materials. However, isolated TiOx species have to be grafted onto the support prior to the zinc oxide species, providing strong evidence for the necessity of TiOSi bridges for high photocatalytic activity in terephthalic acid hydroxylation. |
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Place of Publication |
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Editor |
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Wos |
000328231400044 |
Publication Date |
2013-11-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435;2155-5435; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
22 |
Open Access |
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Notes |
262348 ESMI; FWO; 246791 COUNTATOMS; IAP-PAI; Hercules |
Approved |
Most recent IF: 10.614; 2013 IF: 7.572 |
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Call Number |
UA @ lucian @ c:irua:112502 |
Serial |
1094 |
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Author |
Ranjbar, S.; Hadipour, A.; Vermang, B.; Batuk, M.; Hadermann, J.; Garud, S.; Sahayaraj, S.; Meuris, M.; Brammertz, G.; da Cunha, A.F.; Poortmans, J. |
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Title |
P-N Junction Passivation in Kesterite Solar Cells by Use of Solution-Processed TiO2 Layer |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
IEEE journal of photovoltaics |
Abbreviated Journal |
Ieee J Photovolt |
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| |
Volume |
7 |
Issue |
7 |
Pages |
1130-1135 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In this work, we used a solution-processed TiO2 layer between Cu2ZnSnSe4 and CdS buffer layer to reduce the recombination at the p–n junction. Introducing the TiO2 layer showed a positive impact on VOC but fill factor and efficiency decreased. Using a KCN treatment, we could create openings in the TiO2 layer, as confirmed by transmission electron microscopy measurements. Formation of these openings in the TiO2 layer led to the improvement of the short-circuit current, fill factor, and the efficiency of the modified solar cells. |
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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 |
000404258900026 |
Publication Date |
2017-04-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2156-3381 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.712 |
Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
This work was supported in part by the European Union’s Horizon 2020 research and innovation program under Grant 640868, in part by the Flemish government, Department Economy, Science and Innovation, in part by the FEDER funds through the COMPETE 2020 Programme, and in part by the National Funds through FCT – Portuguese Foundation for Science and Technology under the project UID/CTM/50025/2013. The work of S. Ranjbar was supported by the Portuguese Science and Technology Foundation through Ph.D. grant SFRH/BD/78409/2011. The work of B. Vermang was supported by the Flemish Research Foundation FWO (mandate 12O4215N). |
Approved |
Most recent IF: 3.712 |
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Call Number |
EMAT @ emat @ c:irua:143986 |
Serial |
4583 |
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Author |
Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Turner, S.; Van Tendeloo, G. |
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Title |
Fabrication and Characterization of Fe2O3-Based Nanostructures Functionalized with Metal Particles and Oxide Overlayers |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of advanced microscopy research |
Abbreviated Journal |
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Volume |
10 |
Issue |
10 |
Pages |
239-243 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the design of nanosystems based on functionalized -Fe 2 O 3 nanostructures supported on fluorine-doped tin oxide (FTO) substrates. The target materials were developed by means of hybrid vapor phase approaches, combining plasma assisted-chemical vapor deposition (PA-CVD) for the production of iron(III) oxide systems and the subsequent radio frequency (RF)-sputtering or atomic layer deposition (ALD) for the functionalization with Au nanoparticles or TiO 2 overlayers, respectively. The interplay between material characteristics and the adopted processing parameters was investigated by complementary analytical techniques, encompassing X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), and energy dispersive X-ray spectroscopy (EDXS). The obtained results highlight the possibility of fabricating Au/ -Fe 2 O 3 nanocomposites, with a controlled dispersion and distribution of metal particles, and TiO 2 / -Fe 2 O 3 heterostructures, characterized by an intimate coupling between the constituent oxides. |
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Corporate Author |
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Place of Publication |
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Editor |
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Wos |
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Publication Date |
2015-12-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2156-7573 |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
The authors acknowledge the financial support under the FP7 project “SOLARO- GENIX” (NMP4-SL-2012-310333), as well as Padova University ex-60% 2012–2015 projects, grant n CPDR132937/13 (SOLLEONE), and Regione Lombardia- INSTM ATLANTE program. Stuart Turner acknowledges the FWO Flanders for a post-doctoral scholarship. Thanks are also due to Dr. L. Borgese and Prof. E. Bontempi (Chemistry for Technologies Laboratory, Brescia Univer- sity, Italy) for precious assistance in ALD experiments. |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @ c:irua:132798 |
Serial |
4058 |
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| Permanent link to this record |
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Author |
Maccato, C.; Simon, Q.; Carraro, G.; Barreca, D.; Gasparotto, A.; Lebedev, O.I.; Turner, S.; Van Tendeloo, G. |
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Title |
Zinc and copper oxides functionalized with metal nanoparticles : an insight into their nano-organization |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of advanced microscopy research |
Abbreviated Journal |
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Volume |
7 |
Issue |
2 |
Pages |
84-90 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Ag/ZnO and Au/CuxO (x = 1, 2) nanocomposites supported on Si(100) and polycrystalline Al2O3 were synthesised by hybrid approaches, combining chemical vapor deposition (either thermal or plasma-assisted) of host oxide matrices and subsequent radio frequency-sputtering of guest metal particles. The influence of the adopted synthetic parameters on the nanocomposite morphological and compositional features was investigated by field emission-scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Results confirm the synthesis of ZnO and CuxO nanoarchitectures, characterized by a tailored morphology and an intimate metal/oxide contact. A careful control of the processing conditions enabled a fine tuning of the mutual constituent distribution, opening thus attractive perspectives for the engineering of advanced nanomaterials. |
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Corporate Author |
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Place of Publication |
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Wos |
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Publication Date |
2012-12-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2156-7573;2156-7581; |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
Esteem |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:105298 |
Serial |
3932 |
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Author |
Gauquelin, N.; Zhang, H.; Zhu, G.; Wei, J.Y.T.; Botton, G.A. |
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Title |
Atomic-scale identification of novel planar defect phases in heteroepitaxial YBa2Cu3O7-\delta thin films |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
AIP advances |
Abbreviated Journal |
Aip Adv |
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Volume |
8 |
Issue |
5 |
Pages |
055022 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We have discovered two novel types of planar defects that appear in heteroepitaxial YBa2Cu3O7-delta(YBCO123) thin films, grown by pulsed-laser deposition (PLD) either with or without a La2/3Ca1/3MnO3 (LCMO) overlayer, using the combination of highangle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging and electron energy loss spectroscopy (EELS) mapping for unambiguous identification. These planar lattice defects are based on the intergrowth of either a BaO plane between two CuO chains or multiple Y-O layers between two CuO2 planes, resulting in non-stoichiometric layer sequences that could directly impact the high-Tc superconductivity. (C) 2018 Author(s). |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
Melville, NY |
Editor |
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Language |
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Wos |
000433954000022 |
Publication Date |
2018-05-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2158-3226 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.568 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
; We are thankful to Julia Huang for FIB TEM sample preparation. This work is supported by NSERC (through Discovery Grants to GAB and JYTW) and CIFAR. The electron microscopy work was carried out at the Canadian Centre for Electron Microscopy, a National Facility supported by McMaster University, the Canada Foundation for Innovation and NSERC. N.G. acknowledges H. Idrissi for useful discussions. ; |
Approved |
Most recent IF: 1.568 |
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Call Number |
UA @ lucian @ c:irua:152063 |
Serial |
5013 |
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Author |
Kuznetsov, A.S.; Lu, Y.-G.; Turner, S.; Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Verbeeck, J.; Baranov, A.N.; Moshchalkov, V.V. |
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Title |
Preparation, structural and optical characterization of nanocrystalline ZnO doped with luminescent Ag-nanoclusters |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Optical materials express |
Abbreviated Journal |
Opt Mater Express |
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Volume |
2 |
Issue |
6 |
Pages |
723-734 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nanocrystalline ZnO doped with Ag-nanoclusters has been synthesized by a salt solid state reaction. Three overlapping broad emission bands due to the Ag nanoclusters have been detected at about 570, 750 and 900 nm. These emission bands are excited by an energy transfer from the exciton state of the ZnO host when pumped in the wavelength range from 250 to 400 nm. The 900 nm emission band shows characteristic orbital splitting into three components pointing out that the anisotropic crystalline wurtzite host of ZnO is responsible for this feature. Heat-treatment and temperature dependence studies confirm the origin of these emission bands. An energy level diagram for the emission process and a model for Ag nanoclusters sites are suggested. The emission of nanocrystalline ZnO doped with Ag nanoclusters may be applied for white light generation, displays driven by UV light, down-convertors for solar cells and luminescent lamps. |
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Corporate Author |
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Place of Publication |
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Editor |
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Wos |
000304953700004 |
Publication Date |
2012-04-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2159-3930; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.591 |
Times cited |
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Open Access |
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Notes |
We are grateful to the Methusalem Funding of Flemish Government for the support of this work. Y.-G. L. and S. T. acknowledge funding from the Fund for Scientific Research Flanders (FWO) for a postdoctoral grant and under grant number G056810N. The microscope used in this study was partially financed by the Hercules Foundation. J.V. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No246791 – COUNTATOMS and ERC Starting Grant 278510 VORTEX. The authors acknowledge the guidance of Prof. G. Van Tendeloo, EMAT Antwerpen University, in transmission electron microscopy study in this work. ECASJO_; |
Approved |
Most recent IF: 2.591; 2012 IF: 2.616 |
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Call Number |
UA @ lucian @ c:irua:97709UA @ admin @ c:irua:97709 |
Serial |
2707 |
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Author |
Sankaran, K.J.; Deshmukh, S.; Korneychuk, S.; Yeh, C.-J.; Thomas, J.P.; Drijkoningen, S.; Pobedinskas, P.; Van Bael, M.K.; Verbeeck, J.; Leou, K.-C.; Leung, K.-T.; Roy, S.S.; Lin, I.-N.; Haenen, K. |
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Title |
Fabrication, microstructure, and enhanced thermionic electron emission properties of vertically aligned nitrogen-doped nanocrystalline diamond nanorods |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
MRS communications |
Abbreviated Journal |
Mrs Commun |
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Volume |
8 |
Issue |
3 |
Pages |
1311-1320 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Vertically aligned nitrogen-doped nanocrystalline diamond nanorods are fabricated from nitrogen-doped nanocrystalline diamond films using reactive ion etching in oxygen plasma. These nanorods show enhanced thermionic electron emission (TEE) characteristics, viz.. a high current density of 12.0 mA/cm(2) and a work function value of 4.5 eV with an applied voltage of 3 Vat 923 K. The enhanced TEE characteristics of these nanorods are ascribed to the induction of nanographitic phases at the grain boundaries and the field penetration effect through the local field enhancement from nanorods owing to a high aspect ratio and an excellent field enhancement factor. |
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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 |
000448887900089 |
Publication Date |
2018-08-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2159-6859; 2159-6867 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.01 |
Times cited |
1 |
Open Access |
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Notes |
The authors thank the financial support of the Research Foundation Flanders (FWO) via Research Grant 12I8416N and Research Project 1519817N, and the Methusalem “NANO” network. The Hercules Foundation Flanders is acknowledged for financial support of the Raman equipment. The Qu-Ant-EM microscope used for the TEM experiments was partly funded by the Hercules fund from the Flemish Government. S.K. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. K.J. Sankaran and P. Pobedinskas are Postdoctoral Fellows of FWO. |
Approved |
Most recent IF: 3.01 |
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Call Number |
UA @ admin @ c:irua:155521 |
Serial |
5364 |
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Author |
Bliokh, K.Y.; Schattschneider, P.; Verbeeck, J.; Nori, F. |
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Title |
Electron vortex beams in a magnetic field : a new twist on Landau levels and Aharonov-Bohm states |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
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Volume |
2 |
Issue |
4 |
Pages |
041011-41015 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We examine the propagation of the recently discovered electron vortex beams in a longitudinal magnetic field. We consider both the Aharonov-Bohm configuration with a single flux line and the Landau case of a uniform magnetic field. While stationary Aharonov-Bohm modes represent Bessel beams with flux- and vortex-dependent probability distributions, stationary Landau states manifest themselves as nondiffracting Laguerre-Gaussian beams. Furthermore, the Landau-state beams possess field- and vortex-dependent phases: (i) the Zeeman phase from coupling the quantized angular momentum to the magnetic field and (ii) the Gouy phase, known from optical Laguerre-Gaussian beams. Remarkably, together these phases determine the structure of Landau energy levels. This unified Zeeman-Landau-Gouy phase manifests itself in a nontrivial evolution of images formed by various superpositions of modes. We demonstrate that, depending on the chosen superposition, the image can rotate in a magnetic field with either (i) Larmor, (ii) cyclotron (double-Larmor), or (iii) zero frequency. At the same time, its centroid always follows the classical cyclotron trajectory, in agreement with the Ehrenfest theorem. Interestingly, the nonrotating superpositions reproduce stable multivortex configurations that appear in rotating superfluids. Our results open an avenue for the direct electron-microscopy observation of fundamental properties of free quantum-electron states in magnetic fields. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
College Park, Md |
Editor |
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Language |
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Wos |
000311551100001 |
Publication Date |
2012-11-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2160-3308; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.789 |
Times cited |
130 |
Open Access |
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Notes |
Vortex ECASJO_; |
Approved |
Most recent IF: 12.789; 2012 IF: 6.711 |
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Call Number |
UA @ lucian @ c:irua:105139UA @ admin @ c:irua:105139 |
Serial |
991 |
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Author |
Wu, S.; Luo, X.; Turner, S.; Peng, H.; Lin, W.; Ding, J.; David, A.; Wang, B.; Van Tendeloo, G.; Wang, J.; Wu, T.; |
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Title |
Nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
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Volume |
3 |
Issue |
4 |
Pages |
041027-14 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Resistive switching heterojunctions, which are promising for nonvolatile memory applications, usually share a capacitorlike metal-oxide-metal configuration. Here, we report on the nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures, where the conducting layer near the LaAlO3/SrTiO3 interface serves as the unconventional bottom electrode although both oxides are band insulators. Interestingly, the switching between low-resistance and high-resistance states is accompanied by reversible transitions between tunneling and Ohmic characteristics in the current transport perpendicular to the planes of the heterojunctions. We propose that the observed resistive switching is likely caused by the electric-field-induced drift of charged oxygen vacancies across the LaAlO3/SrTiO3 interface and the creation of defect-induced gap states within the ultrathin LaAlO3 layer. These metal-oxide-oxide heterojunctions with atomically smooth interfaces and defect-controlled transport provide a platform for the development of nonvolatile oxide nanoelectronics that integrate logic and memory devices. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
College Park, Md |
Editor |
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Language |
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Wos |
000328862400001 |
Publication Date |
2013-12-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2160-3308; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.789 |
Times cited |
77 |
Open Access |
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Notes |
FWO;FP7;IFOX; Countatoms; Hercules |
Approved |
Most recent IF: 12.789; 2013 IF: 8.463 |
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Call Number |
UA @ lucian @ c:irua:112524 |
Serial |
2365 |
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Author |
Mahr, C.; Müller-Caspary, K.; Graf, M.; Lackmann, A.; Grieb, T.; Schowalter, M.; Krause, F.F.; Mehrtens, T.; Wittstock, A.; Weissmueller, J.; Rosenauer, A. |
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Title |
Measurement of local crystal lattice strain variations in dealloyed nanoporous gold |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Materials research letters |
Abbreviated Journal |
Mater Res Lett |
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Volume |
6 |
Issue |
1 |
Pages |
84-92 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Reversible macroscopic length changes in nanoporous structures can be achieved by applying electric potentials or by exposing them to different gases or liquids. Thus, these materials are interesting candidates for applications as sensors or actuators. Macroscopic length changes originate from microscopic changes of crystal lattice parameters. In this report, we show spatially resolved measurements of crystal lattice strain in dealloyed nanoporous gold. The results confirm theory by indicating a compression of the lattice along the axis of cylindrically shaped ligaments and an expansion in radial direction. Furthermore, we show that curved npAu surfaces show inward relaxation of the surface layer. [GRAPHICS] . |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Taylor & Francis |
Place of Publication |
Abingdon |
Editor |
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Language |
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Wos |
000428141500013 |
Publication Date |
2017-11-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2166-3831 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.773 |
Times cited |
4 |
Open Access |
Not_Open_Access |
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Notes |
; This work has been supported by the Deutsche Forschungsgemeinschaft (DFG) under contracts no. RO2057/12-1 (SP 6), WI4497/1-1 (SP 2) and WE1424/17-1 (SP 3) within the research unit FOR2213 (www.nagocat.de). K.M.-C acknowledges support by the DFG under contract no. MU3660/1-1 and T.G. under contract no. RO2057/ 11-1. ; |
Approved |
Most recent IF: 4.773 |
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Call Number |
UA @ lucian @ c:irua:150921 |
Serial |
4973 |
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| Permanent link to this record |
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Author |
Rizzo, F.; Augieri, A.; Angrisani Armenio, A.; Galluzzi, V.; Mancini, A.; Pinto, V.; Rufoloni, A.; Vannozzi, A.; Bianchetti, M.; Kursumovic, A.; MacManus-Driscoll, J.L.; Meledin, A.; Van Tendeloo, G.; Celentano, G. |
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Title |
Enhanced 77K vortex-pinning in YBa2Cu3O7−x films with Ba2YTaO6 and mixed Ba2YTaO6 + Ba2YNbO6 nano-columnar inclusions with irreversibility field to 11T |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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Volume |
4 |
Issue |
4 |
Pages |
061101 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Pulsed laser deposited thin YBa2Cu3O7−x (YBCO) films with pinning additions of 5at.% Ba2YTaO6 (BYTO) were compared to films with 2.5at.% Ba2YTaO6 + 2.5at.% Ba2YNbO6 (BYNTO) additions. Excellent magnetic flux-pinning at 77 K was obtained with remarkably high irreversibility fields greater than 10T (YBCO-BYTO) and 11T (YBCO-BYNTO), representing the highest ever achieved values in YBCO films. |
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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 |
000379042400002 |
Publication Date |
2016-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2166-532X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.335 |
Times cited |
19 |
Open Access |
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Notes |
This work was financially supported by EUROTAPES, a collaborative project funded by the European Commission’s Seventh Framework Program (FP7 / 2007-2013) under Grant Agreement no. 280432 |
Approved |
Most recent IF: 4.335 |
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Call Number |
c:irua:133785 |
Serial |
4077 |
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| Permanent link to this record |
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Author |
Benetti, G.; Cavaliere, E.; Canteri, A.; Landini, G.; Rossolini, G.M.; Pallecchi, L.; Chiodi, M.; Van Bael, M.J.; Winckelmans, N.; Bals, S.; Gavioli, L. |
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Title |
Direct synthesis of antimicrobial coatings based on tailored bi-elemental nanoparticles |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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| |
Volume |
5 |
Issue |
5 |
Pages |
036105 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Ultrathin coatings based on bi-elemental nanoparticles (NPs) are very promising to limit the surface-related spread of bacterial pathogens, particularly in nosocomial environments. However, tailoring the synthesis, composition, adhesion to substrate, and antimicrobial spectrum of the coating is an open challenge. Herein, we report on a radically new nanostructured coating, obtained by a one-step gas-phase deposition technique, and composed of bi-elemental Janus type Ag/Ti NPs. The NPs are characterized by a cluster-in-cluster mixing phase with metallic Ag nano-crystals embedded in amorphous TiO2 and present a promising antimicrobial activity including also multidrug resistant strains. We demonstrate the flexibility of the method to tune the embedded Ag nano-crystals dimension, the total relative composition of the coating, and the substrate type, opening the possibility of tailoring the dimension, composition, antimicrobial spectrum, and other physical/chemical properties of such multi-elemental systems. This work is expected to significantly spread the range of applications of NPs coatings, not only as an effective tool in the prevention of healthcare-associated infections but also in other technologically relevant fields like sensors or nano-/micro joining. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000398951000014 |
Publication Date |
2017-03-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2166-532X |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.335 |
Times cited |
21 |
Open Access |
OpenAccess |
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Notes |
We thank Urs Gfeller for the XRF measurements, Francesco Banfi for valuable discussions on the manuscript and Giulio Viano for his valuable support in the microbiological analysis. The authors acknowledge the financial support of Universita Cattolica del Sacro Cuore through D.2.2 and D.3.1 grants and from the European Union through the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). REFERENCES |
Approved |
Most recent IF: 4.335 |
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Call Number |
EMAT @ emat @ c:irua:141723UA @ admin @ c:irua:141723 |
Serial |
4479 |
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| Permanent link to this record |
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Author |
Ramaneti, R.; Sankaran, K.J.; Korneychuk, S.; Yeh, C.J.; Degutis, G.; Leou, K.C.; Verbeeck, J.; Van Bael, M.K.; Lin, I.N.; Haenen, K. |
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Title |
Vertically aligned diamond-graphite hybrid nanorod arrays with superior field electron emission properties |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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| |
Volume |
5 |
Issue |
6 |
Pages |
066102 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
A “patterned-seeding technique” in combination with a “nanodiamond masked reactive ion etching process” is demonstrated for fabricating vertically aligned diamond-graphite hybrid (DGH) nanorod arrays. The DGH nanorod arrays possess superior field electron emission (FEE) behavior with a low turn-on field, long lifetime stability, and large field enhancement factor. Such an enhanced FEE is attributed to the nanocomposite nature of theDGHnanorods, which contain sp(2)-graphitic phases in the boundaries of nano-sized diamond grains. The simplicity in the nanorod fabrication process renders the DGH nanorods of greater potential for the applications as cathodes in field emission displays and microplasma display devices. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license. |
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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 |
000404623000002 |
Publication Date |
2017-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2166-532x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.335 |
Times cited |
16 |
Open Access |
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Notes |
The authors would like to thank the Methusalem “NANO” network for financial support and Mr. B. Ruttens and Professor Jan D'Haen for technical and experimental assistance. K.J. Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). |
Approved |
Most recent IF: 4.335 |
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Call Number |
UA @ admin @ c:irua:152633 |
Serial |
5369 |
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| Permanent link to this record |
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Author |
Do, M.T.; Gauquelin, N.; Nguyen, M.D.; Blom, F.; Verbeeck, J.; Koster, G.; Houwman, E.P.; Rijnders, G. |
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Title |
Interface degradation and field screening mechanism behind bipolar-cycling fatigue in ferroelectric capacitors |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Apl Materials |
Abbreviated Journal |
Apl Mater |
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Volume |
9 |
Issue |
2 |
Pages |
021113 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Polarization fatigue, i.e., the loss of polarization of ferroelectric capacitors upon field cycling, has been widely discussed as an interface related effect. However, mechanism(s) behind the development of fatigue have not been fully identified. Here, we study the fatigue mechanisms in Pt/PbZr0.52Ti0.48O3/SrRuO3 (Pt/PZT/SRO) capacitors in which all layers are fabricated by pulsed laser deposition without breaking the vacuum. With scanning transmission electron microscopy, we observed that in the fatigued capacitor, the Pt/PZT interface becomes structurally degraded, forming a 5 nm-10 nm thick non-ferroelectric layer of crystalline ZrO2 and diffused Pt grains. We then found that the fatigued capacitors can regain the full initial polarization switching if the externally applied field is increased to at least 10 times the switching field of the pristine capacitor. These findings suggest that polarization fatigue is driven by a two-step mechanism. First, the transient depolarization field that repeatedly appears during the domain switching under field cycling causes decomposition of the metal/ferroelectric interface, resulting in a non-ferroelectric degraded layer. Second, this interfacial non-ferroelectric layer screens the external applied field causing an increase in the coercive field beyond the usually applied maximum field and consequently suppresses the polarization switching in the cycled capacitor. Our work clearly confirms the key role of the electrode/ferroelectric interface in the endurance of ferroelectric-based devices. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000630052100006 |
Publication Date |
2021-02-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2166-532x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.335 |
Times cited |
5 |
Open Access |
OpenAccess |
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Notes |
This work was supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek through Grant No. F62.3.15559. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government. N.G. and J.V. acknowledge funding from the GOA project “Solarpaint” of the University of Antwerp. This work has also received funding from the European Union's Horizon 2020 research and innovation program under Grant No. 823717-ESTEEM3. We acknowledge D. Chezganov for his useful insights. |
Approved |
Most recent IF: 4.335 |
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Call Number |
UA @ admin @ c:irua:177663 |
Serial |
6783 |
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| Permanent link to this record |
