Records |
Author |
Du, K.; Guo, L.; Peng, J.; Chen, X.; Zhou, Z.-N.; Zhang, Y.; Zheng, T.; Liang, Y.-P.; Lu, J.-P.; Ni, Z.-H.; Wang, S.-S.; Van Tendeloo, G.; Zhang, Z.; Dong, S.; Tian, H. |
Title |
Direct visualization of irreducible ferrielectricity in crystals |
Type |
A1 Journal article |
Year |
2020 |
Publication |
npj Quantum Materials |
Abbreviated Journal |
|
Volume |
5 |
Issue |
1 |
Pages |
49-7 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In solids, charge polarity can one-to-one correspond to spin polarity phenomenologically, e.g., ferroelectricity/ferromagnetism, antiferroelectricity/antiferromagnetism, and even dipole-vortex/magnetic-vortex, but ferrielectricity/ferrimagnetism kept telling a disparate story in microscopic level. Since the definition of a charge dipole involves more than one ion, there may be multiple choices for a dipole unit, which makes most ferrielectric orders equivalent to ferroelectric ones, i.e., this ferrielectricity is not necessary to be a real independent branch of polarity. In this work, by using the spherical aberration-corrected scanning transmission electron microscope, we visualize a nontrivial ferrielectric structural evolution in BaFe2Se3, in which the development of two polar sub-lattices is out-of-sync, for which we term it as irreducible ferrielectricity. Such irreducible ferrielectricity leads to a non-monotonic behavior for the temperature-dependent polarization, and even a compensation point in the ordered state. Our finding unambiguously distinguishes ferrielectrics from ferroelectrics in solids. |
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 |
000551499400001 |
Publication Date |
2020-07-23 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2397-4648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
; We acknowledge the National Natural Science Foundation of China (Grant Nos. 11834002, 11674055, and 11234011), National Key R&D Program of China 2017YFB0703100, and the 111 Project (Grant No. B16042). K.D. acknowledges the China Scholarship Council (CSC, No.201806320230) for sponsorship and 2019 Zhejiang University Academic Award for Outstanding Doctoral Candidates. We thank Prof. Fang Lin for providing guidance on calculating atoms position and Dr. Andrew Studer for performing neutron powder diffraction. We thank Prof. Sang-Wook Cheong, Prof. Zhigao Sheng, Prof. Qianghua Wang, Prof. Meng Wang, Prof. Renkui Zheng, Prof. Takuya Aoyama, Dr. Zhibo Yan, and Dr. Meifeng Liu for valuable discussion and/or technical help during measurements. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:171225 |
Serial |
6486 |
Permanent link to this record |
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|
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Author |
Verbeeck, J.; Guzzinati, G.; Clark, L.; Juchtmans, R.; Van Boxem, R.; Tian, H.; Béché, A.; Lubk, A.; Van Tendeloo, G. |
Title |
Shaping electron beams for the generation of innovative measurements in the (S)TEM |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Comptes rendus : physique |
Abbreviated Journal |
Cr Phys |
Volume |
15 |
Issue |
2-3 |
Pages |
190-199 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In TEM, a typical goal consists of making a small electron probe in the sample plane in order to obtain high spatial resolution in scanning transmission electron microscopy. In order to do so, the phase of the electron wave is corrected to resemble a spherical wave compensating for aberrations in the magnetic lenses. In this contribution, we discuss the advantage of changing the phase of an electron wave in a specific way in order to obtain fundamentally different electron probes opening up new applications in the (S)TEM. We focus on electron vortex states as a specific family of waves with an azimuthal phase signature and discuss their properties, production and applications. The concepts presented here are rather general and also different classes of probes can be obtained in a similar fashion, showing that electron probes can be tuned to optimize a specific measurement or interaction. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Paris |
Editor |
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Language |
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Wos |
000334013600009 |
Publication Date |
2014-02-01 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1631-0705; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.048 |
Times cited |
22 |
Open Access |
|
Notes |
Vortex ECASJO_; |
Approved |
Most recent IF: 2.048; 2014 IF: 2.035 |
Call Number |
UA @ lucian @ c:irua:116946UA @ admin @ c:irua:116946 |
Serial |
2992 |
Permanent link to this record |
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|
|
Author |
Yang, S.; An, H.; Arnouts, S.; Wang, H.; Yu, X.; de Ruiter, J.; Bals, S.; Altantzis, T.; Weckhuysen, B.M.; van der Stam, W. |
Title |
Halide-guided active site exposure in bismuth electrocatalysts for selective CO₂ conversion into formic acid |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Nature Catalysis |
Abbreviated Journal |
|
Volume |
6 |
Issue |
9 |
Pages |
796-806 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
It remains a challenge to identify the active sites of bismuth catalysts in the electrochemical CO2 reduction reaction. Here we show through in situ characterization that the activation of bismuth oxyhalide electrocatalysts to metallic bismuth is guided by the halides. In situ X-ray diffraction results show that bromide promotes the selective exposure of planar bismuth surfaces, whereas chloride and iodide result in more disordered active sites. Furthermore, we find that bromide-activated bismuth catalysts outperform the chloride and iodide counterparts, achieving high current density (>100 mA cm(-2)) and formic acid selectivity (>90%), suggesting that planar bismuth surfaces are more active for the electrochemical CO2 reduction reaction. In addition, in situ X-ray absorption spectroscopy measurements reveal that the reconstruction proceeds rapidly in chloride-activated bismuth and gradually when bromide is present, facilitating the formation of ordered planar surfaces. These findings show the pivotal role of halogens on selective facet exposure in activated bismuth-based electrocatalysts during the electrochemical CO2 reduction reaction. |
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 |
001050367400001 |
Publication Date |
2023-08-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2520-1158 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
37.8 |
Times cited |
13 |
Open Access |
OpenAccess |
Notes |
B.M.W. acknowledges support from the Strategic UU-TU/e Alliance project 'Joint Centre for Chemergy Research' as well as from the Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO gravitation programme funded by the Ministry of Education, Culture and Science of the government of the Netherlands. S.B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO). S.A. and T.A. acknowledge funding from the University of Antwerp Research fund (BOF). We also thank J. Wijten, J. Janssens and T. Prins (all from the Inorganic Chemistry and Catalysis group, Utrecht University) for helpful technical support. S. Deelen (Faculty of Science, Utrecht University) and L. Wu (Inorganic Chemistry and Catalysis group, Utrecht University) are acknowledged for the design of the in situ XRD cell. We also acknowledge B. Detlefs, P. Glatzel and V. Paidi (ESRF) for the support during the HERFD-XANES measurements on the ID26 beamline of the ESRF. |
Approved |
Most recent IF: 37.8; 2023 IF: NA |
Call Number |
UA @ admin @ c:irua:199190 |
Serial |
8877 |
Permanent link to this record |
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Author |
Yang, S.; An, H.; Anastasiadou, D.; Xu, W.; Wu, L.; Wang, H.; de Ruiter, J.; Arnouts, S.; Figueiredo, M.C.; Bals, S.; Altantzis, T.; van der Stam, W.; Weckhuysen, B.M. |
Title |
Waste-derived copper-lead electrocatalysts for CO₂ reduction |
Type |
A1 Journal article |
Year |
2022 |
Publication |
ChemCatChem |
Abbreviated Journal |
Chemcatchem |
Volume |
14 |
Issue |
18 |
Pages |
e202200754-11 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
It remains a real challenge to control the selectivity of the electrocatalytic CO2 reduction (eCO(2)R) reaction to valuable chemicals and fuels. Most of the electrocatalysts are made of non-renewable metal resources, which hampers their large-scale implementation. Here, we report the preparation of bimetallic copper-lead (CuPb) electrocatalysts from industrial metallurgical waste. The metal ions were extracted from the metallurgical waste through simple chemical treatment with ammonium chloride, and CuxPby electrocatalysts with tunable compositions were fabricated through electrodeposition at varying cathodic potentials. X-ray spectroscopy techniques showed that the pristine electrocatalysts consist of Cu-0, Cu1+ and Pb2+ domains, and no evidence for alloy formation was found. We found a volcano-shape relationship between eCO(2)R selectivity toward two electron products, such as CO, and the elemental ratio of Cu and Pb. A maximum Faradaic efficiency towards CO was found for Cu9.00Pb1.00, which was four times higher than that of pure Cu, under the same electrocatalytic conditions. In situ Raman spectroscopy revealed that the optimal amount of Pb effectively improved the reducibility of the pristine Cu1+ and Pb2+ domains to metallic Cu and Pb, which boosted the selectivity towards CO by synergistic effects. This work provides a framework of thinking to design and tune the selectivity of bimetallic electrocatalysts for CO2 reduction through valorization of metallurgical waste. |
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 |
000853941300001 |
Publication Date |
2022-06-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1867-3880; 1867-3899 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.5 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
S.Y and B.M.W. acknowledge support from the EU Framework Programme for Research and Innovation Horizon 2020 (SOCRATES-721385; project website: http://etn-socrates.eu/). W.v.d.S., M.C.F. and B.M.W. 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). S.A. and T.A. acknowledge funding from the University of Antwerp Research fund (BOF). The Beijing Synchrotron Radiation Facility (1W1B, BSRF) is acknowledged for the beamtime. We are grateful to Annelies van der Bok and Bas Salzmann (Condensed Matter and Interfaces, Utrecht University, UU) for the support with the ICP-OES measurements. The authors thank dr. Robin Geitenbeek, Nikos Nikolopoulos, Ioannis Nikolopoulos, Jochem Wijten and Joris Janssens (Inorganic Chemistry and Catalysis, UU) for helpful discussions and technical support. The authors also thank Yuang Piao (Materials Chemistry and Catalysis, UU) for the help in the preparation of the figures of the article. |
Approved |
Most recent IF: 4.5 |
Call Number |
UA @ admin @ c:irua:190703 |
Serial |
7226 |
Permanent link to this record |
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|
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Author |
Mei, H.; Xu, W.; Wang, C.; Yuan, H.; Zhang, C.; Ding, L.; Zhang, J.; Deng, C.; Wang, Y.; Peeters, F.M. |
Title |
Terahertz magneto-optical properties of bi- and tri-layer graphene |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
30 |
Issue |
17 |
Pages |
175701 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magneto-optical (MO) properties of bi- and tri-layer graphene are investigated utilizing terahertz time-domain spectroscopy (THz TDS) in the presence of a strong magnetic field at room-temperature. In the Faraday configuration and applying optical polarization measurements, we measure the real and imaginary parts of the longitudinal and transverse MO conductivities of different graphene samples. The obtained experimental data fits very well with the classical MO Drude formula. Thus, we are able to obtain the key sample and material parameters of bi- and tri-layer graphene, such as the electron effective mass, the electronic relaxation time and the electron density. It is found that in high magnetic fields the electronic relaxation time tau for bi- and tri-layer graphene increases with magnetic field B roughly in a form tau similar to B-2. Most importantly, we obtain the electron effective mass for bi- and tri-layer graphene at room-temperature under non-resonant conditions. This work shows how the advanced THz MO techniques can be applied for the investigation into fundamental physics properties of atomically thin 2D electronic systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
|
Language |
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Wos |
000429329500001 |
Publication Date |
2018-03-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
11 |
Open Access |
|
Notes |
; This work was supported by the National Natural Science Foundation of China (11574319, 11304317, 11304272), the Ministry of Science and Technology of China (2011YQ130018), the Center of Science and Technology of Hefei Academy of Science, the Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ lucian @ c:irua:150715UA @ admin @ c:irua:150715 |
Serial |
4983 |
Permanent link to this record |
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Author |
Shi, P.; Gielis, J.; Quinn, B.K.; Niklas, K.J.; Ratkowsky, D.A.; Schrader, J.; Ruan, H.; Wang, L.; Niinemets, Ü.; Niinennets, U. |
Title |
‘biogeom’ : an R package for simulating and fitting natural shapes |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Annals of the New York Academy of Sciences |
Abbreviated Journal |
Ann Ny Acad Sci |
Volume |
1516 |
Issue |
1 |
Pages |
123-134 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Many natural objects exhibit radial or axial symmetry in a single plane. However, a universal tool for simulating and fitting the shapes of such objects is lacking. Herein, we present an R package called 'biogeom' that simulates and fits many shapes found in nature. The package incorporates novel universal parametric equations that generate the profiles of bird eggs, flowers, linear and lanceolate leaves, seeds, starfish, and tree-rings, and three growth-rate equations that generate the profiles of ovate leaves and the ontogenetic growth curves of animals and plants. 'biogeom' includes several empirical datasets comprising the boundary coordinates of bird eggs, fruits, lanceolate and ovate leaves, tree rings, seeds, and sea stars. The package can also be applied to other kinds of natural shapes similar to those in the datasets. In addition, the package includes sigmoid curves derived from the three growth-rate equations, which can be used to model animal and plant growth trajectories and predict the times associated with maximum growth rate. 'biogeom' can quantify the intra- or interspecific similarity of natural outlines, and it provides quantitative information of shape and ontogenetic modification of shape with important ecological and evolutionary implications for the growth and form of the living world. |
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 |
000829772300001 |
Publication Date |
2022-07-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0077-8923; 1749-6632 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.2 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 5.2 |
Call Number |
UA @ admin @ c:irua:189314 |
Serial |
7131 |
Permanent link to this record |
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|
Author |
Tian, H.; Schryvers, D.; Claeys, P. |
Title |
Nanodiamonds do not provide unique evidence for a Younger Dryas impact |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Proceedings of the National Academy of Sciences of the United States of America |
Abbreviated Journal |
P Natl Acad Sci Usa |
Volume |
108 |
Issue |
1 |
Pages |
40-44 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Microstructural, δ13C isotope and C/N ratio investigations were conducted on excavated material from the black Younger Dryas boundary in Lommel, Belgium, aiming for a characterisation of the carbon content and structures. Cubic diamond nanoparticles are found in large numbers. The larger ones with diameters around or above 10 nm often exhibit single or multiple twins. The smaller ones around 5 nm in diameter are mostly defect-free. Also larger flake-like particles, around 100 nm in lateral dimension, with a cubic diamond structure are observed as well as large carbon onion structures. The combination of these characteristics does not yield unique evidence for an exogenic impact related to the investigated layer. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000285915000012 |
Publication Date |
2010-12-21 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0027-8424;1091-6490; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.661 |
Times cited |
32 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.661; 2011 IF: 9.681 |
Call Number |
UA @ lucian @ c:irua:88733 |
Serial |
2254 |
Permanent link to this record |
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Author |
Li, Y.; Tan, H.; Lebedev, O.; Verbeeck, J.; Biermans, E.; Van Tendeloo, G.; Su, B.-L. |
Title |
Insight into the growth of multiple branched MnOOH nanorods |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
Volume |
10 |
Issue |
7 |
Pages |
2969-2976 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Multiple branched manganese oxide hydroxide (MnOOH) nanorods prepared by a hydrothermal process were extensively studied by transmission electron microscopy (TEM). A model of the branch formation is proposed together with a study of the interface structure. The sword-like tip plays a crucial role for the nanorods to form different shapes. Importantly, the branching occurs at an angle of around either 57 degrees or 123 degrees. Specifically, a (111) twin plane can only be formed at the interface with a 123 degrees angle. The interfaces formed with a 57 degrees angle usually contain edge dislocations. Electron energy loss spectroscopy (EELS) demonstrates that the whole crystal has a uniform chemical composition. Interestingly, an epitaxial growth of Mn3O4 at the radial surface was also observed under electron beam irradiation; this is because of the rough purification of the products. The proposed mechanism is expected to shed light on the branched/dendrite nanostructure growth and to provide opportunities for further novel nanomaterial structure growth and design. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000279422700027 |
Publication Date |
2010-06-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1528-7483;1528-7505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.055 |
Times cited |
41 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
Call Number |
UA @ lucian @ c:irua:83886UA @ admin @ c:irua:83886 |
Serial |
1672 |
Permanent link to this record |
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Author |
Wu, L.; Kolmeijer, K.E.; Zhang, Y.; An, H.; Arnouts, S.; Bals, S.; Altantzis, T.; Hofmann, J.P.; Costa Figueiredo, M.; Hensen, E.J.M.; Weckhuysen, B.M.; van der Stam, W. |
Title |
Stabilization effects in binary colloidal Cu and Ag nanoparticle electrodes under electrochemical CO₂ reduction conditions |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
13 |
Issue |
9 |
Pages |
4835-4844 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
Nanoparticle modified electrodes constitute an attractive way to tailor-make efficient carbon dioxide (CO2) reduction catalysts. However, the restructuring and sintering processes of nanoparticles under electrochemical reaction conditions not only impedes the widespread application of nanoparticle catalysts, but also misleads the interpretation of the selectivity of the nanocatalysts. Here, we colloidally synthesized metallic copper (Cu) and silver (Ag) nanoparticles with a narrow size distribution (<10%) and utilized them in electrochemical CO2 reduction reactions. Monometallic Cu and Ag nanoparticle electrodes showed severe nanoparticle sintering already at low overpotential of -0.8 V vs. RHE, as evidenced by ex situ SEM investigations, and potential-dependent variations in product selectivity that resemble bulk Cu (14% for ethylene at -1.3 V vs. RHE) and Ag (69% for carbon monoxide at -1.0 V vs. RHE). However, by co-deposition of Cu and Ag nanoparticles, a nanoparticle stabilization effect was observed between Cu and Ag, and the sintering process was greatly suppressed at CO2 reducing potentials (-0.8 V vs. RHE). Furthermore, by varying the Cu/Ag nanoparticle ratio, the CO2 reduction reaction (CO2RR) selectivity towards methane (maximum of 20.6% for dense Cu-2.5-Ag-1 electrodes) and C-2 products (maximum of 15.7% for dense Cu-1-Ag-1 electrodes) can be tuned, which is attributed to a synergistic effect between neighbouring Ag and Cu nanoparticles. We attribute the stabilization of the nanoparticles to the positive enthalpies of Cu-Ag solid solutions, which prevents the dissolution-redeposition induced particle growth under CO2RR conditions. The observed nanoparticle stabilization effect enables the design and fabrication of active CO2 reduction nanocatalysts with high durability. |
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 |
000628024200011 |
Publication Date |
2021-02-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2040-3364 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
24 |
Open Access |
OpenAccess |
Notes |
This work is funded by the Strategic UU-TU/e Alliance project ‘Joint Centre for Chemergy Research’ (budget holder B. M. W.). S. B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO). S. A. and T. A. acknowledge funding from the University of Antwerp Research fund (BOF). We thank Eric Hellebrand (Faculty of Geosciences, Utrecht University) for the assistance in SEM measurements. Dr Ramon Oord (ARC Chemical Building Blocks Consortium, Faculty of Science, Utrecht University) is acknowledged for assisting with the grazing incidence XRD measurements; sygma |
Approved |
Most recent IF: 7.367 |
Call Number |
UA @ admin @ c:irua:176723 |
Serial |
6737 |
Permanent link to this record |
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Author |
Meledina, M.; Turner, S.; Galvita, V.V.; Poelman, H.; Marin, G.B.; Van Tendeloo, G. |
Title |
Local environment of Fe dopants in nanoscale Fe : CeO2-x oxygen storage material |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
7 |
Issue |
7 |
Pages |
3196-3204 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Nanoscale Fe : CeO2-x oxygen storage material for the process of chemical looping has been investigated by advanced transmission electron microscopy and electron energy-loss spectroscopy before and after a model looping procedure, consisting of redox cycles at heightened temperature. Separately, the activity of the nanomaterial has been tested in a toluene total oxidation reaction. The results show that the material consists of ceria nanoparticles, doped with single Fe atoms and small FeOx clusters. The iron ion is partially present as Fe3+ in a solid solution within the ceria lattice. Furthermore, enrichment of reduced Fe2+ species is observed in nanovoids present in the ceria nanoparticles, as well as at the ceria surface. After chemical looping, agglomeration occurs and reduced nanoclusters appear at ceria grain boundaries formed by sintering. These clusters originate from surface Fe2+ aggregation, and from bulk Fe3+, which “leaks out” in reduced state after cycling to a slightly more agglomerated form. The activity of Fe : CeO2 during the toluene total oxidation part of the chemical looping cycle is ensured by the dopant Fe in the Fe1-xCexO2 solid solution, and by surface Fe species. These measurements on a model Fe : CeO2-x oxygen storage material give a unique insight into the behavior of dopants within a nanosized ceria host, and allow to interpret a plethora of (doped) cerium oxide-based reactions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000349473200046 |
Publication Date |
2015-01-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 7.367; 2015 IF: 7.394 |
Call Number |
c:irua:125299 |
Serial |
1828 |
Permanent link to this record |
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Author |
Yin, S.; Tian, H.; Ren, Z.; Wei, X.; Chao, C.; Pei, J.; Li, X.; Xu, G.; Shen, G.; Han, G. |
Title |
Octahedral-shaped perovskite nanocrystals and their visible-light photocatalytic activity |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemical communications |
Abbreviated Journal |
Chem Commun |
Volume |
50 |
Issue |
45 |
Pages |
6027-6030 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Octahedral-shaped perovskite PbTiO3 nanocrystals (PT OCT) with well-defined {111} facets exposed have been successfully synthesized via a facile hydrothermal method by using LiNO3 as an ion surfactant. The Li-O bond on the surface of PT OCT nanocrystals is essential to the stability of such nanocrystals and also results in a dramatic high visible-light photocatalytic activity. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000335984700022 |
Publication Date |
2014-04-15 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1359-7345;1364-548X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.319 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.319; 2014 IF: 6.834 |
Call Number |
UA @ lucian @ c:irua:117690 |
Serial |
2428 |
Permanent link to this record |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Verbeeck, J.; Tian, H.; Tan, H.; Dik, J.; Radepont, M.; Cotte, M. |
Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
83 |
Issue |
4 |
Pages |
1214-1223 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000287176900011 |
Publication Date |
2011-02-14 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0003-2700;1520-6882; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
113 |
Open Access |
|
Notes |
Iuap; Fwo |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
Call Number |
UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794 |
Serial |
632 |
Permanent link to this record |
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Author |
Yuan, H.; Debroye, E.; Bladt, E.; Lu, G.; Keshavarz, M.; Janssen, K.P.F.; Roeffaers, M.B.J.; Bals, S.; Sargent, E.H.; Hofkens, J. |
Title |
Imaging heterogeneously distributed photo-active traps in perovskite single crystals |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
30 |
Issue |
30 |
Pages |
1705494 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Organic-inorganic halide perovskites (OIHPs) have demonstrated outstanding energy conversion efficiency in solar cells and light-emitting devices. In spite of intensive developments in both materials and devices, electronic traps and defects that significantly affect their device properties remain under-investigated. Particularly, it remains challenging to identify and to resolve traps individually at the nanoscopic scale. Here, photo-active traps (PATs) are mapped over OIHP nanocrystal morphology of different crystallinity by means of correlative optical differential super-resolution localization microscopy (Delta-SRLM) and electron microscopy. Stochastic and monolithic photoluminescence intermittency due to individual PATs is observed on monocrystalline and polycrystalline OIHP nanocrystals. Delta-SRLM reveals a heterogeneous PAT distribution across nanocrystals and determines the PAT density to be 1.3 x 10(14) and 8 x 10(13) cm(-3) for polycrystalline and for monocrystalline nanocrystals, respectively. The higher PAT density in polycrystalline nanocrystals is likely related to an increased defect density. Moreover, monocrystalline nanocrystals that are prepared in an oxygen and moisture-free environment show a similar PAT density as that prepared at ambient conditions, excluding oxygen or moisture as chief causes of PATs. Hence, it is conduded that the PATs come from inherent structural defects in the material, which suggests that the PAT density can be reduced by improving crystalline quality of the material. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000428793600009 |
Publication Date |
2018-02-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
29 |
Open Access |
OpenAccess |
Notes |
; The authors acknowledge financial support from the Research Foundation-Flanders (FWO, grant G.0197.11, G.0962.13, G0B39.15, ZW1509 GOH6316N, postdoctoral fellowships to H.Y., E.D., and K.P.F.J., doctoral fellowship to E.B.), KU Leuven Research Fund (C14/15/053), the Flemish government through long term structural funding Methusalem (CASAS2, Meth/15/04), the Hercules foundation (HER/11/14), the Belgian Federal Science Policy Office (IAP-PH05), the EC through the Marie Curie ITN project iSwitch (GA-642196), and the ERC project LIGHT (GA-307523). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS). G.L. acknowledges Key University Science Research Project of Jiangsu Province (No. 17KJA150005). E.H.S. acknowledges support from the Ontario Research Fund – Research Excellence Program. ; ecassara |
Approved |
Most recent IF: 19.791 |
Call Number |
UA @ lucian @ c:irua:150826UA @ admin @ c:irua:150826 |
Serial |
4970 |
Permanent link to this record |
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Author |
Ren, Z.; Wu, M.; Chen, X.; Li, W.; Li, M.; Wang, F.; Tian, H.; Chen, J.; Xie, Y.; Mai, J.; Li, X.; Lu, X.; Lu, Y.; Zhang, H.; Van Tendeloo, G.; Zhang, Z.; Han, G. |
Title |
Electrostatic force-driven oxide heteroepitaxy for interface control |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
30 |
Issue |
38 |
Pages |
1707017 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Oxide heterostructure interfaces create a platform to induce intriguing electric and magnetic functionalities for possible future devices. A general approach to control growth and interface structure of oxide heterostructures will offer a great opportunity for understanding and manipulating the functionalities. Here, it is reported that an electrostatic force, originating from a polar ferroelectric surface, can be used to drive oxide heteroepitaxy, giving rise to an atomically sharp and coherent interface by using a low-temperature solution method. These heterostructures adopt a fascinating selective growth, and show a saturation thickness and the reconstructed interface with concentrated charges accumulation. The ferroelectric polarization screening, developing from a solid-liquid interface to the heterostructure interface, is decisive for the specific growth. At the interface, a charge transfer and accumulation take place for electrical compensation. The facile approach presented here can be extremely useful for controlling oxide heteroepitaxy and producing intriguing interface functionality via electrostatic engineering. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000444671900002 |
Publication Date |
2018-08-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
4 |
Open Access |
Not_Open_Access |
Notes |
; Z.H.R., M.J.W., and X.C. contributed equally to this work. This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 51232006, 51472218, 11474249, 61574123, 11374009, and 11234011), the National 973 Program of China (Grant No. 2015CB654901), National Young 1000 Talents Program of China, the Fundamental Research Funds for the Central Universities (Grant No. 2017FZA4008), and the 111 Project under Grant No. B16042. J.M. and X.L. gratefully thank the beam time and technical supports provided by 23A SWAXS beamline at NSRRC, Hsinchu. ; |
Approved |
Most recent IF: 19.791 |
Call Number |
UA @ lucian @ c:irua:153628 |
Serial |
5098 |
Permanent link to this record |
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Author |
Ramachandran, R.K.; Filez, M.; Solano, E.; Poelman, H.; Minjauw, M.M.; Van Daele, M.; Feng, J.-Y.; La Porta, A.; Altantzis, T.; Fonda, E.; Coati, A.; Garreau, Y.; Bals, S.; Marin, G.B.; Detavernier, C.; Dendooven, J. |
Title |
Chemical and Structural Configuration of Pt Doped Metal Oxide Thin Films Prepared by Atomic Layer Deposition |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
31 |
Issue |
31 |
Pages |
9673-9683 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
Pt doped semiconducting metal oxides and Pt metal clusters embedded in an oxide matrix are of interest for applications such as catalysis and gas sensing, energy storage and memory devices. Accurate tuning of the dopant level is crucial for adjusting the properties of these materials. Here, a novel atomic layer deposition (ALD) based method for doping Pt into In2O3 in specific, and metals in metal oxides in general, is demonstrated. This approach combines alternating exposures of Pt and In2O3 ALD processes in a single ‘supercycle’, followed by supercycle repetition leading to multilayered nanocomposites. The atomic level control of ALD and its conformal nature make the method suitable for accurate dopant control even on high surface area supports. Oxidation state, local structural environment and crystalline phase of the embedded Pt dopants were obtained by means of X-ray characterization methods and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). In addition, this approach allows characterization of the nucleation stages of metal ALD processes, by stacking those states multiple times in an oxide matrix. Regardless of experimental conditions, a few Pt ALD cycles leads to the formation of oxidized Pt species due to their highly dispersed nature, as proven by X-ray absorption spectroscopy (XAS). Grazing-incidence small-angle X-ray scattering (GISAXS) and highresolution scanning transmission electron microscopy, combined with energy dispersive X-ray spectroscopy (HR-STEM/EDXS) show that Pt is evenly distributed in the In2O3 metal oxide matrix without the formation of clusters. For a larger number of Pt ALD
cycles, typ. > 10, the oxidation state gradually evolves towards fully metallic, and metallic Pt clusters are obtained within the In2O3 metal oxide matrix. This work reveals how tuning of the ALD supercycle approach for Pt doping allows controlled engineering of the Pt compositional and structural configuration within a metal oxide matrix. |
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 |
000502418000010 |
Publication Date |
2019-11-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
OpenAccess |
Notes |
This research was supported by the Flemish Research Foundation (FWO-Vlaanderen), the Flemish Government (Long term structural funding – Methusalem funding and Medium scale research infrastructure funding-Hercules funding), the Special Research Fund BOF of Ghent University (GOA 01G01513) and the CALIPSO Trans National Access Program funded by the European Commission in supplying financing of travel costs. We are grateful to the SIXS and SAMBA-SOLEIL staff for smoothly running the beamline facilities. J.D. and R.K.R. are postdoctoral fellows of the FWO. |
Approved |
Most recent IF: 9.466 |
Call Number |
EMAT @ emat @c:irua:164056 |
Serial |
5380 |
Permanent link to this record |
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Author |
Palgrave, R.G.; Borisov, P.; Dyer, M.S.; McMitchell, S.R.C.; Darling, G.R.; Claridge, J.B.; Batuk, M.; Tan, H.; Tian, H.; Verbeeck, J.; Hadermann, J.; Rosseinsky, M.J.; |
Title |
Artificial construction of the layered Ruddlesden-Popper manganite La2Sr2Mn3O10 by reflection high energy electron diffraction monitored pulsed laser deposition |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
134 |
Issue |
18 |
Pages |
7700-7714 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Pulsed laser deposition has been used to artificially construct the n = 3 Ruddlesden Popper structure La2Sr2Mn3O10 in epitaxial thin film form by sequentially layering La1-xSrxMnO3 and SrO unit cells aided by in situ reflection high energy electron diffraction monitoring. The interval deposition technique was used to promote two-dimensional SrO growth. X-ray diffraction and cross-sectional transmission electron microscopy indicated that the trilayer structure had been formed. A site ordering was found to differ from that expected thermodynamically, with the smaller Sr2+ predominantly on the R site due to kinetic trapping of the deposited cation sequence. A dependence of the out-of-plane lattice parameter on growth pressure was interpreted as changing the oxygen content of the films. Magnetic and transport measurements on fully oxygenated films indicated a frustrated magnetic ground state characterized as a spin glass-like magnetic phase with the glass temperature T-g approximate to 34 K. The magnetic frustration has a clear in-plane (ab) magnetic anisotropy, which is maintained up to temperatures of 150 K. Density functional theory calculations suggest competing antiferromagnetic and ferromagnetic long-range orders, which are proposed as the origin of the low-temperature glassy state. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000303696200029 |
Publication Date |
2012-03-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
27 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
Call Number |
UA @ lucian @ c:irua:98947UA @ admin @ c:irua:98947 |
Serial |
153 |
Permanent link to this record |
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Author |
Quan, L.N.; Ma, D.; Zhao, Y.; Voznyy, O.; Yuan, H.; Bladt, E.; Pan, J.; de Arquer, F.P.G.; Sabatini, R.; Piontkowski, Z.; Emwas, A.-H.; Todorovic, P.; Quintero-Bermudez, R.; Walters, G.; Fan, J.Z.; Liu, M.; Tan, H.; Saidaminov, M., I; Gao, L.; Li, Y.; Anjum, D.H.; Wei, N.; Tang, J.; McCamant, D.W.; Roeffaers, M.B.J.; Bals, S.; Hofkens, J.; Bakr, O.M.; Lu, Z.-H.; Sargent, E.H. |
Title |
Edge stabilization in reduced-dimensional perovskites |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat Commun |
Volume |
11 |
Issue |
1 |
Pages |
170 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Reduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite light-emitting diodes is their limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack is powered by photogenerated and electrically-injected carriers that diffuse to the nanoplatelet edges and produce superoxide. We report an edge-stabilization strategy wherein phosphine oxides passivate unsaturated lead sites during perovskite crystallization. With this approach, we synthesize reduced-dimensional perovskites that exhibit 97 +/- 3% photoluminescence quantum yields and stabilities that exceed 300 h upon continuous illumination in an air ambient. We achieve green-emitting devices with a peak external quantum efficiency (EQE) of 14% at 1000 cd m(-2); their maximum luminance is 4.5 x 10(4) cd m(-2) (corresponding to an EQE of 5%); and, at 4000 cd m(-2), they achieve an operational half-lifetime of 3.5 h. |
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 |
000551458200001 |
Publication Date |
2020-01-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
16.6 |
Times cited |
147 |
Open Access |
OpenAccess |
Notes |
; This publication is based in part on work supported by an award (KUS-11-009-21) from the King Abdullah University of Science and Technology (KAUST), by the Ontario Research Fund Research Excellence Program, by the Ontario Research Fund (ORF), by the Natural Sciences and Engineering Research Council (NSERC) of Canada, and by the US Department of Navy, Office of Naval Research (Grant Award No. N00014-17-12524). H.Y. acknowledges the Research Foundation-Flanders (FWO Vlaanderen) for a postdoctoral fellowship. E.B. gratefully acknowledges financial support by the Research Foundation-Flanders (FWO Vlaanderen). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #815128-REALNANO). M.B.J.R. and J.H. acknowledge the Research Foundation-Flanders (FWO, Grants G.0962.13, G.0B39.15, AKUL/11/14 and G0H6316N), KU Leuven Research Fund (C14/15/053) and the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ ERC Grant Agreement No. [307523], ERC-Stg LIGHT to M.B.J.R. DFT calculations were performed on the IBM BlueGene Q supercomputer with support from the Southern Ontario Smart Computing Innovation Platform (SOSCIP). M.I.S. acknowledges the Banting Postdoctoral Fellowship program from the Natural Sciences and Engineering Research Council of Canada (NSERC). H.T. acknowledges the Netherlands Organisation for Scientific Research (NWO) for a Rubicon grant (680-50-1511). ; sygma |
Approved |
Most recent IF: 16.6; 2020 IF: 12.124 |
Call Number |
UA @ admin @ c:irua:171327 |
Serial |
6496 |
Permanent link to this record |
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Author |
Dehhaghi, S.; Choobchian, S.; Ghobadian, B.; Farhadian, H.; Viira, A.-H.; Stefanie, H.I.; Van Passel, S.; Azadi, H. |
Title |
Five-year development plans of renewable energy policies in Iran : a content analysis |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Sustainability |
Abbreviated Journal |
Sustainability-Basel |
Volume |
14 |
Issue |
3 |
Pages |
1501 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
Renewable energy (RE) policies can play an effective role in the development of renewable resources. The main goal of this paper was to conduct a content analysis on RE development policies in Iran's five-year National Development Plan (NDP) by investigating upstream national documents. To achieve the goal, 29 upstream documents related to RE were identified and analyzed through a systematic literature review. Then, a qualitative content analysis was applied to analyze the documents. The results showed that Iran's current RE policies need to be reviewed, reformed, and strengthened. For example, lack of sufficient attention to renewable heat and fuel was one of the deficiencies of RE policies in Iran's five-year NDP. The decentralization of policymaking in the unified organization was also one of the weaknesses in the policymaking process of the RE. Iran can develop sustainable and clean RE policies by using sources such as solar, wind, geothermal, hydropower, wave, and tidal power. The paper concludes that, although RE policies have the potential for development in Iran due to environmental, social, and economic advantages, they could face some infrastructural, managerial, socio-cultural, and economic challenges. Accordingly, effective and innovative policymaking is required to meet such challenges. |
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 |
000754912800001 |
Publication Date |
2022-01-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2071-1050 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.9 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.9 |
Call Number |
UA @ admin @ c:irua:186501 |
Serial |
7358 |
Permanent link to this record |
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Author |
Chaves, A.; Azadani, J.G.; Alsalman, H.; da Costa, D.R.; Frisenda, R.; Chaves, A.J.; Song, S.H.; Kim, Y.D.; He, D.; Zhou, J.; Castellanos-Gomez, A.; Peeters, F.M.; Liu, Z.; Hinkle, C.L.; Oh, S.-H.; Ye, P.D.; Koester, S.J.; Lee, Y.H.; Avouris, P.; Wang, X.; Low, T. |
Title |
Bandgap engineering of two-dimensional semiconductor materials |
Type |
A1 Journal article |
Year |
2020 |
Publication |
npj 2D Materials and Applications |
Abbreviated Journal |
|
Volume |
4 |
Issue |
1 |
Pages |
29-21 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Semiconductors are the basis of many vital technologies such as electronics, computing, communications, optoelectronics, and sensing. Modern semiconductor technology can trace its origins to the invention of the point contact transistor in 1947. This demonstration paved the way for the development of discrete and integrated semiconductor devices and circuits that has helped to build a modern society where semiconductors are ubiquitous components of everyday life. A key property that determines the semiconductor electrical and optical properties is the bandgap. Beyond graphene, recently discovered two-dimensional (2D) materials possess semiconducting bandgaps ranging from the terahertz and mid-infrared in bilayer graphene and black phosphorus, visible in transition metal dichalcogenides, to the ultraviolet in hexagonal boron nitride. In particular, these 2D materials were demonstrated to exhibit highly tunable bandgaps, achieved via the control of layers number, heterostructuring, strain engineering, chemical doping, alloying, intercalation, substrate engineering, as well as an external electric field. We provide a review of the basic physical principles of these various techniques on the engineering of quasi-particle and optical bandgaps, their bandgap tunability, potentials and limitations in practical realization in future 2D device technologies. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000565588500001 |
Publication Date |
2020-08-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
2397-7132 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
604 |
Open Access |
|
Notes |
; Discussions and interactions with D.R. Reichman, F. Tavazza, N.M.R. Peres, and K. Choudhary are gratefully acknowledged. A.C. acknowledges financial support by CNPq, through the PRONEX/FUNCAP and PQ programs. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 755655, ERCStG 2017 project 2D-TOPSENSE). Computational support from the Minnesota Supercomputing Institute (MSI) and EU Graphene Flagship funding (Grant Graphene Core 2, 785219) is acknowledged. R.F. acknowledges support from the Netherlands Organization for Scientific Research (NWO) through the research program Rubicon with project number 680-50-1515. D.H., J.Z., and X.W. acknowledge support by National Natural Science Foundation of China 61734003, 61521001, 61704073, 51861145202, and 61851401, and National Key Basic Research Program of China 2015CB921600 and 2018YFB2200500. J.Z. and Z.L. acknowledge support by RG7/18, MOE2017-T2-2-136, MOE2018-T3-1-002, and A*Star QTE program. S.H.S. and Y.H.L. acknowledge the support from IBS-R011-D1. Y.D.K. is supported by Samsung Research and Incubation Funding Center of Samsung Electronics under Project Number SRFC-TB1803-04. S.J.K acknowledges financial support by the National Science Foundation (NSF), under award DMR-1921629. T.L. and J.G.A. acknowledge funding support from NSF/DMREF under Grant Agreement No. 1921629. S.-H.O. acknowledges support from the U.S. National Science Foundation (NSF ECCS 1809723) and Samsung Global Research Outreach (GRO) project. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:172069 |
Serial |
6459 |
Permanent link to this record |
|
|
|
Author |
Filez, M.; Redekop, E.A.; Poelman, H.; Galvita, V.V.; Meledina, M.; Turner, S.; Van Tendeloo, G.; Detavernier, C.; Marin, G.B. |
Title |
One-pot synthesis of Pt catalysts based on layered double hydroxides: an application in propane dehydrogenation |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Catalysis science & technology |
Abbreviated Journal |
Catal Sci Technol |
Volume |
6 |
Issue |
6 |
Pages |
1863-1869 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Simple methods for producing noble metal catalysts with well-defined active sites and improved performance are highly desired in the chemical industry. However, the development of such methods still presents a formidable synthetic challenge. Here, we demonstrate a one-pot synthesis route for the controlled production of bimetallic Pt–In catalysts based on the single-step formation of Mg,Al,Pt,In-containing layered double hydroxides (LDHs). Besides their simple synthesis, these Pt–In catalysts exhibit superior propane dehydrogenation activity compared to their multi-step synthesized analogs. The presented material serves as a showcase for the one-pot synthesis of a broader class of LDH-derived mono- and multimetallic Pt catalysts. The compositional flexibility provided by LDH materials can pave the way towards highperforming Pt-based catalysts with tunable physicochemical properties. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000372172800031 |
Publication Date |
2015-10-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2044-4753 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.773 |
Times cited |
12 |
Open Access |
|
Notes |
This work was supported by the Fund for Scientific Research Flanders (FWO: G.0209.11), the ‘Long Term Structural Methusalem Funding by the Flemish Government’, the IAP 7/05 Interuniversity Attraction Poles Programme – Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) by supplying financing of beam time at the DUBBLE beamline of the ESRF and travel costs and a post-doctoral fellowship for S. T. The authors acknowledge the assistance from the DUBBLE (XAS campaign 26-01-979) and SuperXAS staff (Proposal 20131191). E. A. Redekop acknowledges the Marie Curie International Incoming Fellowship granted by the European Commission (Grant Agreement No. 301703). The authors also express their gratitude to O. Janssens for performing ex situ XRD characterization. |
Approved |
Most recent IF: 5.773 |
Call Number |
c:irua:133167 |
Serial |
4057 |
Permanent link to this record |
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|
|
Author |
Molina, L.; Tan, H.; Biermans, E.; Batenburg, K.J.; Verbeeck, J.; Bals, S.; Van Tendeloo, G. |
Title |
Barrier efficiency of sponge-like La2Zr2O7 buffer layers for YBCO-coated conductors |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
24 |
Issue |
6 |
Pages |
065019-065019,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different film processing methods can yield similar microstructural features such as nanovoids and nanometer-sized La2Zr2O7 grains. Nanoporosity is a typical feature found in such films and the implications for the functionality of the films are investigated by a combination of scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) and quantitative electron tomography. Chemical solution based La2Zr2O7 films deposited on flexible Ni5 at.%W substrates with a {100}lang001rang biaxial texture were prepared for an in-depth characterization. A sponge-like structure composed of nanometer-sized voids is revealed by high-angle annular dark-field scanning transmission electron microscopy in combination with electron tomography. A three-dimensional quantification of nanovoids in the La2Zr2O7 film is obtained on a local scale. Mostly non-interconnected highly faceted nanovoids compromise more than one-fifth of the investigated sample volume. The diffusion barrier efficiency of a 170 nm thick La2Zr2O7 film is investigated by STEM-EELS, yielding a 1.8 ± 0.2 nm oxide layer beyond which no significant nickel diffusion can be detected and intermixing is observed. This is of particular significance for the functionality of YBa2Cu3O7 − δ coated conductor architectures based on solution derived La2Zr2O7 films as diffusion barriers. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000290472900021 |
Publication Date |
2011-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
31 |
Open Access |
|
Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 2.878; 2011 IF: 2.662 |
Call Number |
UA @ lucian @ c:irua:88639UA @ admin @ c:irua:88639 |
Serial |
221 |
Permanent link to this record |
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|
|
Author |
Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Filonenko, V.P.; Gonnissen, J.; Tan, H.; Verbeeck, J.; Gemmi, M.; Antipov, E.V.; Rosner, H. |
Title |
Direct space structure solution from precession electron diffraction data: resolving heavy and light scatterers in Pb13Mn9O25 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
110 |
Issue |
7 |
Pages |
881-890 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure of a novel compound Pb13Mn9O25 has been determined through a direct space structure solution with a Monte-Carlo-based global optimization using precession electron diffraction data (a=14.177(3) Å, c=3.9320(7) Å, SG P4/m, RF=0.239) and compositional information obtained from energy dispersive X-ray analysis and electron energy loss spectroscopy. This allowed to obtain a reliable structural model even despite the simultaneous presence of both heavy (Pb) and light (O) scattering elements and to validate the accuracy of the electron diffraction-based structure refinement. This provides an important benchmark for further studies of complex structural problems with electron diffraction techniques. Pb13Mn9O25 has an anion- and cation-deficient perovskite-based structure with the A-positions filled by the Pb atoms and 9/13 of the B positions filled by the Mn atoms in an ordered manner. MnO6 octahedra and MnO5 tetragonal pyramids form a network by sharing common corners. Tunnels are formed in the network due to an ordered arrangement of vacancies at the B-sublattice. These tunnels provide sufficient space for localization of the lone 6s2 electron pairs of the Pb2+ cations, suggested as the driving force for the structural difference between Pb13Mn9O25 and the manganites of alkali-earth elements with similar compositions. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000280050900023 |
Publication Date |
2010-04-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
24 |
Open Access |
|
Notes |
Fwo; Bof; Esteem |
Approved |
Most recent IF: 2.843; 2010 IF: 2.063 |
Call Number |
UA @ lucian @ c:irua:84085UA @ admin @ c:irua:84085 |
Serial |
721 |
Permanent link to this record |
|
|
|
Author |
Van Rompaey, S.; Dachraoui, W.; Turner, S.; Podyacheva, O.Y.; Tan, H.; Verbeeck, J.; Abakumov, A.; Hadermann, J. |
Title |
Layered oxygen vacancy ordering in Nb-doped SrCo1-xFexO3-\delta perovskite |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Zeitschrift für Kristallographie |
Abbreviated Journal |
Z Krist-Cryst Mater |
Volume |
228 |
Issue |
1 |
Pages |
28-34 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure of SrCo0.7Fe0.2Nb0.1O2.72 was determined using a combination of precession electron diffraction (PED), high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and spatially resolved electron energy loss spectroscopy (STEM-EELS). The structure has a tetragonal P4/mmm symmetry with cell parameters a = b = a(p), c = 2a(p) (a(p) being the cell parameter of the perovskite parent structure). Octahedral BO2 layers alternate with the anion-deficient BO1.4 layers, the different B cations are randomly distributed over both layers. The specific feature of the SrCo0.7Fe0.2NB0.1O2.72 microstructure is a presence of extensive nanoscale twinning resulting in domains with alignment of the tetragonal c-axis along all three cubic direction of the perovskite subcell. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
München |
Editor |
|
Language |
|
Wos |
000315475900004 |
Publication Date |
2013-01-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2194-4946; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.179 |
Times cited |
9 |
Open Access |
|
Notes |
Fwo; Countatoms |
Approved |
Most recent IF: 3.179; 2013 IF: NA |
Call Number |
UA @ lucian @ c:irua:107698UA @ admin @ c:irua:107698 |
Serial |
1808 |
Permanent link to this record |
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|
|
Author |
Abakumov, A.M.; Hadermann, J.; Tsirlin, A.A.; Tan, H.; Verbeeck, J.; Zhang, H.; Dikarev, E.V.; Shpanchenko, R.V.; Antipov, E.V. |
Title |
Original close-packed structure and magnetic properties of the Pb4Mn9O20 manganite |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
Volume |
182 |
Issue |
8 |
Pages |
2231-2238 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure of the Pb4Mn9O20 compound (previously known as Pb0.43MnO2.18) was solved from powder X-ray diffraction, electron diffraction, and high resolution electron microscopy data (S.G. Pnma, a=13.8888(2) Å, b=11.2665(2) Å, c=9.9867(1) Å, RI=0.016, RP=0.047). The structure is based on a 6H (cch)2 close packing of pure oxygen h-type (O16) layers alternating with mixed c-type (Pb4O12) layers. The Mn atoms occupy octahedral interstices formed by the oxygen atoms of the close-packed layers. The MnO6 octahedra share edges within the layers, whereas the octahedra in neighboring layers are linked through corner sharing. The relationship with the closely related Pb3Mn7O15 structure is discussed. Magnetization measurements reveal a peculiar magnetic behavior with a phase transition at 52 K, a small net magnetization below the transition temperature, and a tendency towards spin freezing. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000269066400035 |
Publication Date |
2009-06-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.299 |
Times cited |
5 |
Open Access |
|
Notes |
The authors are grateful to Christoph Geibel for the help in magnetization measurements. A.Ts. acknowledges MPI CKS for hospitality and financial support during the stay. E.D. thanks the National Science Foundation (CHE-0718900) for financial support. This work was supported by the Russian Foundation of Basic Research (RFBR Grants 07-03-00664-a, 06-03-90168-a and 07-03-00890-a). The authors acknowledge financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. |
Approved |
Most recent IF: 2.299; 2009 IF: 2.340 |
Call Number |
UA @ lucian @ c:irua:78935UA @ admin @ c:irua:78935 |
Serial |
2529 |
Permanent link to this record |
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|
|
Author |
Zhou, Y.; Che, F.; Liu, M.; Zou, C.; Liang, Z.; De Luna, P.; Yuan, H.; Li, J.; Wang, Z.; Xie, H.; Li, H.; Chen, P.; Bladt, E.; Quintero-Bermudez, R.; Sham, T.-K.; Bals, S.; Hofkens, J.; Sinton, D.; Chen, G.; Sargent, E.H. |
Title |
Dopant-induced electron localization drives CO2 reduction to C2 hydrocarbons |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Nature chemistry |
Abbreviated Journal |
Nat Chem |
Volume |
10 |
Issue |
10 |
Pages |
974-980 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The electrochemical reduction of CO2 to multi-carbon products has attracted much attention because it provides an avenue to the synthesis of value-added carbon-based fuels and feedstocks using renewable electricity. Unfortunately, the efficiency of CO2 conversion to C-2 products remains below that necessary for its implementation at scale. Modifying the local electronic structure of copper with positive valence sites has been predicted to boost conversion to C-2 products. Here, we use boron to tune the ratio of Cu delta+ to Cu-0 active sites and improve both stability and C-2-product generation. Simulations show that the ability to tune the average oxidation state of copper enables control over CO adsorption and dimerization, and makes it possible to implement a preference for the electrosynthesis of C-2 products. We report experimentally a C-2 Faradaic efficiency of 79 +/- 2% on boron-doped copper catalysts and further show that boron doping leads to catalysts that are stable for in excess of similar to 40 hours while electrochemically reducing CO2 to multi-carbon hydrocarbons. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000442395200013 |
Publication Date |
2018-07-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1755-4330; 1755-4349 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
25.87 |
Times cited |
700 |
Open Access |
OpenAccess |
Notes |
; This work was supported financially by funding from TOTAL S.A., the Ontario Research Fund: Research Excellence Program, the Natural Sciences and Engineering Research Council of Canada, the CIFAR Bio-Inspired Solar Energy programme, a University of Toronto Connaught grant, the Ministry of Science, Natural Science Foundation of China (21471040, 21271055 and 21501035), the Innovation-Driven Plan in Central South University project (2017CX003), a project from State Key Laboratory of Powder Metallurgy in Central South University, the Thousand Youth Talents Plan of China and Hundred Youth Talents Program of Hunan and the China Scholarship Council programme. This work benefited from the soft X-ray microcharacterization beamline at CLS, sector 20BM at the APS and the Ontario Centre for the Characterisation of Advanced Materials at the University of Toronto. H.Y. acknowledges financial support from the Research Foundation-Flanders (FWO postdoctoral fellowship). C.Z. acknowledges support from the International Academic Exchange Fund for Joint PhD Students from Tianjin University. P.D.L. acknowledges financial support from the Natural Sciences and Engineering Research Council in the form of the Canada Graduate Scholarship-Doctoral award. S.B. and E.B. acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). The authors thank B. Zhang, N. Wang, C. T. Dinh, T. Zhuang, J. Li and Y. Zhao for fruitful discussions, as well as Y. Hu and Q. Xiao from CLS, and Z. Finfrock and M. Ward from APS for their help during the course of study. Computations were performed on the SOSCIP Consortium's Blue Gene/Q computing platform. SOSCIP is funded by the Federal Economic Development Agency of Southern Ontario, the Province of Ontario, IBM Canada, Ontario Centres of Excellence, Mitacs and 15 Ontario academic member institutions. ; ecas_sara |
Approved |
Most recent IF: 25.87 |
Call Number |
UA @ lucian @ c:irua:153693UA @ admin @ c:irua:153693 |
Serial |
5091 |
Permanent link to this record |
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|
Author |
Yuan, H.F.; Xu, W.; Zhao, X.N.; Song, D.; Zhang, G.R.; Xiao, Y.M.; Ding, L.; Peeters, F.M. |
Title |
Quantum and transport mobilities of a Na3Bi-based three-dimensional Dirac system |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
99 |
Issue |
23 |
Pages |
235303 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electronic and transport properties of a three-dimensional (3D) Dirac system are investigated theoretically, which is motivated by recent experimental measurements on quantum and transport mobilities in the 3D Dirac semimetal Na3Bi by J. Xiong et al. [Science 350, 413 (2015); Europhys. Lett. 114, 27002 (2016)]. The electron Hamiltonian is taken from a simplified k center dot p approach. From the obtained electronic band structure and the Fermi energy, we explain why the anomalous effect induced by the chiral anomaly and the Berry curvature in the energy band can be observed experimentally in magnetotransport coefficients in both low-and high-density samples. Moreover, the quantum and transport mobilities are calculated on the basis of the momentum-balance equation derived from a semiclassical Boltzmann equation with the electron-impurity interaction. The quantum and transport mobilities obtained from this study agree both qualitatively and quantitatively with those measured experimentally. We also examine the electron mobilities along different crystal directions in Na3Bi and find them largely anisotropic. The theoretical findings from this work can be helpful in gaining an in-depth understanding of the experimental results and of the basic electronic and transport properties of newly developed 3D Dirac systems. |
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 |
|
Wos |
000471983500006 |
Publication Date |
2019-06-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:161329 |
Serial |
5425 |
Permanent link to this record |
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|
|
Author |
Tian, H.; Schryvers, D.; Shabalovskaya, S.; van Humbeeck, J. |
Title |
Microstructure of surface and subsurface layers of a Ni-Ti shape memory microwire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
15 |
Issue |
|
Pages |
62-70 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The microstructure of a 55 Êm diameter, cold-worked Ni-Ti microwire is investigated by different transmission electron microscopy techniques. The surface consists of a few hundred nanometer thick oxide layer composed of TiO and TiO2 with a small fraction of inhomogeneously distributed Ni. The interior of the wire has a core-shell structure with primarily B2 grains in the 1 Êm thick shell, and heavily twinned B19 martensite in the core. This core-shell structure can be explained by a concentration gradient of the alloying elements resulting in a structure separation due to the strong temperature dependence of the martensitic start temperature. Moreover, in between the B2 part of the metallic core-shell and the oxide layer, a Ni3Ti interfacial layer is detected. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
Language |
|
Wos |
000262912700009 |
Publication Date |
2009-01-15 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
15 |
Open Access |
|
Notes |
FWO G.0465.05; Multimat |
Approved |
Most recent IF: 1.891; 2009 IF: 3.035 |
Call Number |
UA @ lucian @ c:irua:72319 |
Serial |
2074 |
Permanent link to this record |
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|
|
Author |
He, Z.; Tian, H.; Deng, G.; Xu, Q.; Van Tendeloo, G. |
Title |
Microstructure of bilayer manganite PrCa2Mn2O7 showing charge/orbital ordering |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
102 |
Issue |
21 |
Pages |
212902-212905 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The microstructure of the charge/orbital ordering Ruddleden-Popper phase PrCa2Mn2O7 was studied by transmission electron microscopy along both the [001] and the [110] orientation. Three coexisting charge/orbital ordering phases CO1, CO2, and CO3 were observed along the [001] orientation at room temperature. Different from the one-dimensional modulation in the CO1 and CO2 phase, the CO3 phase is characterized by two sets of mutually perpendicular structural modulations. From [110] high angle annular dark field-scanning transmission electron microscopy, we found that the Pr atoms locate in-between the bilayer MnO6 octahedra, which is different from the previous reports. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000320620400056 |
Publication Date |
2013-05-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
4 |
Open Access |
|
Notes |
Countatoms |
Approved |
Most recent IF: 3.411; 2013 IF: 3.515 |
Call Number |
UA @ lucian @ c:irua:108762 |
Serial |
2068 |
Permanent link to this record |
|
|
|
Author |
Monico, L.; Janssens, K.; Miliani, C.; Brunetti, B.G.; Vagnini, M.; Vanmeert, F.; Falkenberg, G.; Abakumov, A.; Lu, Y.; Tian, H.; Verbeeck, J.; Radepont, M.; Cotte, M.; Hendriks, E.; Geldof, M.; van der Loeff, L.; Salvant, J.; Menu, M.; |
Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 3 : synthesis, characterization, and detection of different crystal forms of the chrome yellow pigment |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
85 |
Issue |
2 |
Pages |
860-867 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The painter, Vincent van Gogh, and some of his contemporaries frequently made use of the pigment chrome yellow that is known to show a tendency toward darkening. This pigment may correspond to various chemical compounds such as PbCrO4 and PbCr1-xSxO4, that may each be present in various crystallographic forms with different tendencies toward degradation. Investigations by X-ray diffraction (XRD), mid-Fourier Transform infrared (FTIR), and Raman instruments (benchtop and portable) and synchrotron radiation-based micro-XRD and X-ray absorption near edge structure spectroscopy performed on oil-paint models, prepared with in-house synthesized PbCrO4 and PbCr1-xSxO4, permitted us to characterize the spectroscopic features of the various forms. On the basis of these results, an extended study has been carried out on historic paint tubes and on embedded paint microsamples taken from yellow-orange/pale yellow areas of 12 Van Gogh paintings, demonstrating that Van Gogh effectively made use of different chrome yellow types. This conclusion was also confirmed by in situ mid-FTIR investigations on Van Goghs Portrait of Gauguin (Van Gogh Museum, Amsterdam). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000313668400031 |
Publication Date |
2012-10-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0003-2700;1520-6882; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
79 |
Open Access |
|
Notes |
Goa; Fwo |
Approved |
Most recent IF: 6.32; 2013 IF: 5.825 |
Call Number |
UA @ lucian @ c:irua:108707UA @ admin @ c:irua:108707 |
Serial |
631 |
Permanent link to this record |
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|
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Author |
Shabalovskaya, S.A.; Tian, H.; Anderegg, J.W.; Schryvers, D.U.; Carroll, W.U.; van Humbeeck, J. |
Title |
The influence of surface oxides on the distribution and release of nickel from Nitinol wires |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Biomaterials |
Abbreviated Journal |
Biomaterials |
Volume |
30 |
Issue |
4 |
Pages |
468-477 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The patterns of Ni release from Nitinol vary depending on the type of material (NiTi alloys with low or no processing versus commercial wires or sheets). A thick TiO2 layer generated on the wire surface during processing is often considered as a reliable barrier against Ni release. The present study of Nitinol wires with surface oxides resulting from production was conducted to identify the sources of Ni release and its distribution in the surface sublayers. The chemistry and topography of the surfaces of Nitinol wires drawn using different techniques were studied with XPS and SEM. The distribution of Ni into surface depth and the surface oxide thickness were evaluated using Auger spectroscopy, TEM with FIB and ELNES. Ni release was estimated using either ICPA or AAS. Potentiodynamic potential polarization of selected wires was performed in as-received state with no strain and in treated strained samples. Wire samples in the as-received state showed low breakdown potentials (200 mV); the improved corrosion resistance of these wires after treatment was not affected by strain. It is shown how processing techniques affect surface topography, chemistry and also Ni release. Nitinol wires with the thickest surface oxide TiO2 (up to 720 nm) showed the highest Ni release, attributed to the presence of particles of essentially pure Ni whose number and size increased while approaching the interface between the surface and the bulk. The biological implications of high and lasting Ni release are also discussed. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Guildford |
Editor |
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Language |
|
Wos |
000262065500006 |
Publication Date |
2008-11-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0142-9612; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.402 |
Times cited |
102 |
Open Access |
|
Notes |
Fwo; G.0465.05 |
Approved |
Most recent IF: 8.402; 2009 IF: 7.365 |
Call Number |
UA @ lucian @ c:irua:72320 |
Serial |
1641 |
Permanent link to this record |