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Records |
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Author |
Verberck, B.; Popov, V.N.; Nikolaev, A.V.; Lamoen, D. |
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Title |
Valence electronic charge density of distorted C60-monomers in polymerized KC60 and RbC60 |
Type |
A1 Journal article |
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Year |
2004 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
121 |
Issue |
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Pages |
321 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000222112100035 |
Publication Date |
2004-06-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.965 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.965; 2004 IF: 3.105 |
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Call Number |
UA @ lucian @ c:irua:47380 |
Serial |
3830 |
Permanent link to this record |
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Author |
Govaerts, K.; Saniz, R.; Partoens, B.; Lamoen, D. |
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Title |
van der Waals bonding and the quasiparticle band structure of SnO from first principles |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
87 |
Issue |
23 |
Pages |
235210-235217 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
In this work we have investigated the structural and electronic properties of SnO, which is built up from layers kept together by van der Waals (vdW) forces. The combination of a vdW functional within density functional theory (DFT) and quasiparticle band structure calculations within the GW approximation provides accurate values for the lattice parameters, atomic positions, and the electronic band structure including the fundamental (indirect) and the optical (direct) band gap without the need of experimental or empirical input. A systematic comparison is made between different levels of self-consistency within the GW approach {following the scheme of Shishkin et al. [Phys. Rev. B 75, 235102 (2007)]} and the results are compared with DFT and hybrid functional results. Furthermore, the effect of the vdW-corrected functional as a starting point for the GW calculation of the band gap has been investigated. Finally, we studied the effect of the vdW functional on the electron charge density. |
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Place of Publication |
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Editor |
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Wos |
000321061000003 |
Publication Date |
2013-07-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
50 |
Open Access |
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Notes |
IWT; FWO; Hercules |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
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Call Number |
UA @ lucian @ c:irua:109596 |
Serial |
3835 |
Permanent link to this record |
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Author |
Rahemi, V.; Sarmadian, N.; Anaf, W.; Janssens, K.; Lamoen, D.; Partoens, B.; De Wael, K. |
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Title |
Unique opto-electronic structure and photo reduction properties of sulfur doped lead chromates explaining their instability in paintings |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
89 |
Issue |
89 |
Pages |
3326-3334 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artists material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods. Pure PbCrO4 (crocoite in its natural form) has a deep yellow color and is relatively stable, while the co-precipitate with lead sulfate (PbCr1-xSxO4) has a paler shade and seems to degrade faster. This degradation is assumed to be related to the reduction of Cr(VI) to Cr(III). We show that on increasing the sulfur(S)-content in chrome yellow, the band gap increases. Typically, when increasing the band gap, one might assume that a decrease in photo activity is the result. However, the photo activity relative to the Cr content, and thus Cr reduction, of sulfur-rich PbCr1-xSxO4 is found to be much higher compared to the sulfur-poor or non-doped lead chromates. This discrepancy can be explained by the evolution of the crystal and electronic structure as function of the sulfur content: first-principles density functional theory calculations show that both the absorption coefficient and reflection coefficients of the lead chromates change as a result of the sulfate doping in such a way that the generation of electron-hole pairs under illumination relative to the total Cr content increases. These changes in the material properties explain why paler shade yellow colors of this pigment are more prone to discoloration. The electronic structure calculations also demonstrate that lead chromate and its co-precipitates are p-type semiconductors, which explains the observed reduction reaction. As understanding this phenomenon is valuable in the field of cultural heritage, this study is the first joint action of photo-electrochemical measurements and first-principles calculations to approve the higher tendency of sulfur-rich lead chromates to darken. |
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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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Wos |
000397478300015 |
Publication Date |
2017-02-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
7 |
Open Access |
OpenAccess |
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Notes |
; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government, department EWI. The BOF-GOA action SOLARPAINT of the University of Antwerp Research Council is acknowledged for financial support. W.A. acknowledges support from BELSPO project S2-ART. Dr. L. Monico and Dr. C. Miliani (ISTM, Perugia) are gratefully acknowledged for helpful discussions and for providing some of the initial batches of the materials studied. ; |
Approved |
Most recent IF: 6.32 |
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Call Number |
UA @ lucian @ c:irua:140886 |
Serial |
4451 |
Permanent link to this record |
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Author |
Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Batuk, M.; Hadermann, J.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. |
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Title |
Effect of zinc oxide modification by indium oxide on microstructure, adsorbed surface species, and sensitivity to CO |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Frontiers in materials |
Abbreviated Journal |
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Volume |
6 |
Issue |
6 |
Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Additives in semiconductor metal oxides are commonly used to improve sensing behavior of gas sensors. Due to complicated effects of additives on the materials microstructure, adsorption sites and reactivity to target gases the sensing mechanism with modified metal oxides is a matter of thorough research. Herein, we establish the promoting effect of nanocrystalline zinc oxide modification by 1-7 at.% of indium on the sensitivity to CO gas due to improved nanostructure dispersion and concentration of active sites. The sensing materials were synthesized via an aqueous coprecipitation route. Materials composition, particle size and BET area were evaluated using X-ray diffraction, nitrogen adsorption isotherms, high-resolution electron microscopy techniques and EDX-mapping. Surface species of chemisorbed oxygen, OH-groups, and acid sites were characterized by probe molecule techniques and infrared spectroscopy. It was found that particle size of zinc oxide decreased and the BET area increased with the amount of indium oxide. The additive was observed as amorphous indium oxide segregated on agglomerated ZnO nanocrystals. The measured concentration of surface species was higher on In2O3-modified zinc oxide. With the increase of indium oxide content, the sensor response of ZnO/In2O3 to CO was improved. Using in situ infrared spectroscopy, it was shown that oxidation of CO molecules was enhanced on the modified zinc oxide surface. The effect of modifier was attributed to promotion of surface OH-groups and enhancement of CO oxidation on the segregated indium ions, as suggested by DFT in previous work. |
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Corporate Author |
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Wos |
000461540600001 |
Publication Date |
2019-03-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2296-8016 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
11 |
Open Access |
OpenAccess |
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Notes |
; Research was supported by the grant from Russian Science Foundation (project No. 18-73-00071). ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:158540 |
Serial |
5205 |
Permanent link to this record |
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Author |
Paulus, A.; Hendrickx, M.; Bercx, M.; Karakulina, O.M.; Kirsanova, M.A.; Lamoen, D.; Hadermann, J.; Abakumov, A.M.; Van Bael, M.K.; Hardy, A. |
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Title |
An in-depth study of Sn substitution in Li-rich/Mn-rich NMC as a cathode material for Li-ion batteries |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
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Volume |
49 |
Issue |
30 |
Pages |
10486-10497 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Layered Li-rich/Mn-rich NMC (LMR-NMC) is characterized by high initial specific capacities of more than 250 mA h g(-1), lower cost due to a lower Co content and higher thermal stability than LiCoO2. However, its commercialisation is currently still hampered by significant voltage fade, which is caused by irreversible transition metal ion migration to emptied Li positionsviatetrahedral interstices upon electrochemical cycling. This structural change is strongly correlated with anionic redox chemistry of the oxygen sublattice and has a detrimental effect on electrochemical performance. In a fully charged state, up to 4.8 Vvs.Li/Li+, Mn4+ is prone to migrate to the Li layer. The replacement of Mn4+ for an isovalent cation such as Sn4+ which does not tend to adopt tetrahedral coordination and shows a higher metal-oxygen bond strength is considered to be a viable strategy to stabilize the layered structure upon extended electrochemical cycling, hereby decreasing voltage fade. The influence of Sn4+ on the voltage fade in partially charged LMR-NMC is not yet reported in the literature, and therefore, we have investigated the structure and the corresponding electrochemical properties of LMR-NMC with different Sn concentrations. We determined the substitution limit of Sn4+ in Li1.2Ni0.13Co0.13Mn0.54-xSnxO2 by powder X-ray diffraction and transmission electron microscopy to be x approximate to 0.045. The limited solubility of Sn is subsequently confirmed by density functional theory calculations. Voltage fade for x= 0 andx= 0.027 has been comparatively assessed within the 3.00 V-4.55 V (vs.Li/Li+) potential window, from which it is concluded that replacing Mn4+ by Sn4+ cannot be considered as a viable strategy to inhibit voltage fade within this window, at least with the given restricted doping level. |
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Place of Publication |
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Wos |
000555330900018 |
Publication Date |
2020-07-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
; The authors acknowledge Research Foundation Flanders (FWO) project number G040116N for funding. The authors are grateful to Dr Ken Elen and Greet Cuyvers (imo-imomec, UHasselt and imec) for respectively preliminary PXRD measurements and performing ICP-AES on the monometal precursors. Dr Dmitry Rupasov (Skolkovo Institute of Science and Technology) is acknowledged for performing TGA measurements on the metal sulfate precursors. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 4; 2020 IF: 4.029 |
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Call Number |
UA @ admin @ c:irua:171149 |
Serial |
6450 |
Permanent link to this record |
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Author |
Mayda, S.; Monico, L.; Krishnan, D.; De Meyer, S.; Cotte, M.; Garrevoet, J.; Falkenberg, G.; Sandu, I.C.A.; Partoens, B.; Lamoen, D.; Romani, A.; Miliani, C.; Verbeeck, J.; Janssens, K. |
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Title |
A combined experimental and computational approach to understanding CdS pigment oxidation in a renowned early 20th century painting |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Chemistry of materials |
Abbreviated Journal |
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Volume |
35 |
Issue |
24 |
Pages |
10403-10415 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
Cadmium sulfide (CdS)-based yellow pigments have been used in a number of early 20th century artworks, including The Scream series painted by Edvard Munch. Some of these unique paintings are threatened by the discoloration of these CdS-based yellow oil paints because of the oxidation of the original sulfides to sulfates. The experimental data obtained here prove that moisture and cadmium chloride compounds play a key role in promoting such oxidation. To clarify how these two factors effectively prompt the process, we studied the band alignment between CdS, CdCl2, and Cd-(OH)Cl as well as the radicals center dot OH and H3O center dot by density functional theory (DFT) methods. Our results show that a stack of several layers of Cd-(OH)Cl creates a pocket of positive holes at the Cl-terminated surface and a pocket of electrons at the OH-terminated surface by leading in a difference in ionization energy at both surfaces. The resulting band alignment indicates that Cd-(OH)Cl can indeed play the role of an oxidative catalyst for CdS in a moist environment, thus providing an explanation for the experimental evidence. |
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Wos |
001133000900001 |
Publication Date |
2023-12-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756; 1520-5002 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
8.6 |
Times cited |
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Open Access |
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Notes |
The experimental research on the cadmium yellow powders/paint mock-ups and The Scream (ca. 1910) was financially supported by the European Union, research projects IPERION-CH (H2020-INFRAIA-2014-2015, GA no. 654028) and IPERION-HS (H2020-INFRAIA-2019-1, GA no. 871034) and the project AMIS within the program Dipartimenti di Eccellenza 2018-2022 (funded by MUR and the University of Perugia). For the beamtime grants received, the authors thank the ESRF-ID21 beamline (experiments HG64 and HG95), the DESY-P06 beamline, a member of the Helmholtz Association HGF (experiments I-20130221 EC and I-20160126 EC), and the project CALIPSOplus under the GA no. 730872 from the E.U. Framework Programme for Research and Innovation Horizon 2020. All of the staff of the MUNCH Museum (Conservation Department) is acknowledged for their collaboration. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO – Vlaanderen and the Flemish Government, Department EWI. |
Approved |
Most recent IF: 8.6; 2023 IF: 9.466 |
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Call Number |
UA @ admin @ c:irua:202836 |
Serial |
8999 |
Permanent link to this record |
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Author |
Müller, E.; Kruse, P.; Gerthsen, D.; Schowalter, M.; Rosenauer, A.; Lamoen, D.; Kling, R. |
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Title |
Measurement of the mean inner potential of ZnO nanorods by transmission electron holography |
Type |
A1 Journal article |
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Year |
2005 |
Publication |
Microscopy of Semiconducting Materials |
Abbreviated Journal |
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Volume |
107 |
Issue |
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Pages |
303-306 |
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Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Wos |
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Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
SPRINGER PROCEEDINGS IN PHYSICS |
Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0930-8989 |
ISBN |
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Additional Links |
UA library record; WoS full record; |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:72914 |
Serial |
1962 |
Permanent link to this record |
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Author |
Matthai, C.C.; Lamoen, D.; March, N.H. |
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Title |
Melting temperatures and possible precursor plastic phases of CCl4and GeI4as a function of pressure |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physics and chemistry of liquids |
Abbreviated Journal |
Phys Chem Liq |
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Volume |
54 |
Issue |
54 |
Pages |
130-134 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The motivation for the present study is to be found in the recent experiments of Fuchizaki and Hamaya on GeI4. They observed a rapid increase in the melting temperature Tm in going from atmospheric pressure to p ~ 2.6 GPa. Tm was found to be largely independent of pressure above this value. In this paper, heuristic arguments are presented to support the idea that until some critical pressure, a crystalline phase of SnI4, CCl4 and GeI4 molecular solids melts into a low density liquid. However, at this critical pressure, a phase boundary intersects Tm(p), separating a low density liquid phase from a high density liquid. The new phase boundary is between the crystal and an amorphous molecular solid with increasing polymerisation as the pressure is increased. |
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Place of Publication |
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Wos |
000365724100012 |
Publication Date |
2015-07-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9104 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.145 |
Times cited |
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Open Access |
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Notes |
NHM wishes to thank Professors D. Lamoen and C. Van Alsenoy for making possible the continuing affiliation of |
Approved |
Most recent IF: 1.145 |
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Call Number |
c:irua:130190 |
Serial |
4029 |
Permanent link to this record |
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Author |
Govaerts, K.; Partoens, B.; Lamoen, D. |
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Title |
Extended homologous series of Sn–O layered systems: A first-principles study |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
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Volume |
243 |
Issue |
243 |
Pages |
36-43 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Apart from the most studied tin-oxide compounds, SnO and SnO2, intermediate states have been claimed to exist for more than a hundred years. In addition to the known homologous series (Seko et al., Phys. Rev. Lett. 100, 045702 (2008)), we here predict the existence of several new compounds with an O concentration between 50 % (SnO) and 67 % (SnO2). All these intermediate compounds are constructed from removing one or more (101) oxygen layers of SnO2. Since the van der Waals (vdW) interaction is known to be important for the Sn-Sn interlayer distances, we use a vdW-corrected functional, and compare these results with results obtained with PBE and hybrid functionals. We present the electronic properties of the intermediate structures and we observe a decrease of the band gap when (i) the O concentration increases and (ii) more SnO-like units are present for a given concentration. The contribution of the different atoms to the valence and conduction band is also investigated. |
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Wos |
000381544200007 |
Publication Date |
2016-06-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0038-1098 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.554 |
Times cited |
10 |
Open Access |
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Notes |
We gratefully acknowledge financial support from a GOA fund of the University of Antwerp. K.G. thanks the University of Antwerp for a PhD fellowship. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government – department EWI. |
Approved |
Most recent IF: 1.554 |
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Call Number |
c:irua:134037 |
Serial |
4085 |
Permanent link to this record |
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Author |
Nikolaev, A.V.; Lamoen, D.; Partoens, B. |
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Title |
Extension of the basis set of linearized augmented plane wave (LAPW) method by using supplemented tight binding basis functions |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
145 |
Issue |
145 |
Pages |
014101 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
In order to increase the accuracy of the linearized augmented plane wave (LAPW) method, we present a new approach where the plane wave basis function is augmented by two different atomic radial components constructed at two different linearization energies corresponding to two different electron bands (or energy windows). We demonstrate that this case can be reduced to the standard treatment within the LAPW paradigm where the usual basis set is enriched by the basis functions of the tight binding type, which go to zero with zero derivative at the sphere boundary. We show that the task is closely related with the problem of extended core states which is currently solved by applying the LAPW method with local orbitals (LAPW+LO). In comparison with LAPW+LO, the number of supplemented basis functions in our approach is doubled, which opens up a new channel for the extension of the LAPW and LAPW+LO basis sets. The appearance of new supplemented basis functions absent in the LAPW+LO treatment is closely related with the existence of the ul-component in the canonical LAPW method. We discuss properties of additional tight binding basis functions and apply the extended basis set for computation of electron energy bands of lanthanum (face and body centered structures) and hexagonal close packed lattice of cadmium. We demonstrate that the new treatment gives lower total energies in comparison with both canonical LAPW and LAPW+LO, with the energy difference more pronounced for intermediate and poor LAPW basis sets. |
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Wos |
000379584700003 |
Publication Date |
2016-07-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.965 |
Times cited |
11 |
Open Access |
|
|
Notes |
A.V.N. acknowledges useful discussions with B. Verberck, E. V. Tkalya, and A. V. Bibikov. |
Approved |
Most recent IF: 2.965 |
|
Call Number |
c:irua:134290 |
Serial |
4099 |
Permanent link to this record |
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Author |
Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. |
|
Title |
First-principles study of the optoelectronic properties and photovoltaic absorber layer efficiency of Cu-based chalcogenides |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
Volume |
120 |
Issue |
120 |
Pages |
085707 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
Cu-based chalcogenides are promising materials for thin-film solar cells with more than 20% measured
cell efficiency. Using first-principles calculations based on density functional theory, the
optoelectronic properties of a group of Cu-based chalcogenides Cu2-II-IV-VI4 is studied. They are
then screened with the aim of identifying potential absorber materials for photovoltaic applications.
The spectroscopic limited maximum efficiency (SLME) introduced by Yu and Zunger [Phys. Rev.
Lett. 108, 068701 (2012)] is used as a metric for the screening. After constructing the currentvoltage
curve, the SLME is calculated from the maximum power output. The role of the nature of
the band gap, direct or indirect, and also of the absorptivity of the studied materials on the maximum
theoretical power conversion efficiency is studied. Our results show that Cu2II-GeSe4 with
II¼ Cd and Hg, and Cu2-II-SnS4 with II ¼ Cd, Hg, and Zn have a higher theoretical efficiency
compared with the materials currently used as absorber layer. |
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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 ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000383913400074 |
Publication Date |
2016-08-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
|
ISSN |
0021-8979 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.068 |
Times cited |
29 |
Open Access |
|
|
Notes |
We acknowledge the financial support from the FWO-Vlaanderen through project G.0150.13N and a GOA fund from the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), bothfunded by the FWO-Vlaanderen and the Flemish Government–department EWI. |
Approved |
Most recent IF: 2.068 |
|
Call Number |
c:irua:135089 |
Serial |
4113 |
Permanent link to this record |
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Author |
Matsubara, M.; Saniz, R.; Partoens, B.; Lamoen, D. |
|
Title |
Doping anatase TiO2with group V-b and VI-b transition metal atoms: a hybrid functional first-principles study |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
Volume |
19 |
Issue |
19 |
Pages |
1945-1952 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
We investigate the role of transition metal atoms of group V-b (V, Nb, Ta) and VI-b (Cr, Mo, W) as n- or p-type dopants in anatase TiO$2$ using thermodynamic
principles and density functional theory with the Heyd-Scuseria-Ernzerhof HSE06 hybrid functional. The HSE06 functional provides a realistic value for the band gap, which ensures a correct classification of dopants as shallow or deep donors or acceptors. Defect formation energies and thermodynamic transition levels are calculated taking into account the constraints imposed by the stability of TiO$2$ and the solubility limit of the impurities.
Nb, Ta, W and Mo are identified as shallow donors. Although W provides two electrons, Nb and Ta show a considerable lower formation energy, in particular under O-poor conditions. Mo donates in principle one electron, but under specific conditions can turn into a double donor. V impurities are deep donors and Cr
shows up as an amphoteric defect, thereby acting as an electron trapping center in n-type TiO$_2$ especially under O-rich conditions. A comparison with the available experimental data yields excellent agreement. |
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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 ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000394426400027 |
Publication Date |
2016-12-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
|
ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.123 |
Times cited |
19 |
Open Access |
OpenAccess |
|
Notes |
We gratefully acknowledge financial support from the IWTVlaanderenthrough projects G.0191.08 and G.0150.13, and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, which is funded by the Hercules foundation. M. M. acknowledges financial support from the GOA project ‘‘XANES meets ELNES’’ of the University of Antwerp. |
Approved |
Most recent IF: 4.123 |
|
Call Number |
EMAT @ emat @ c:irua:140835 |
Serial |
4421 |
Permanent link to this record |
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Author |
Jacobs, W.; Reynaerts, C.; Andries, S.; van den Akker, S.; Moonen, N.; Lamoen, D. |
|
Title |
Analyzing the dispersion of cargo vapors around a ship’s superstructure by means of wind tunnel experiments |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of marine science and technology |
Abbreviated Journal |
J Mar Sci Tech-Japan |
|
Volume |
21 |
Issue |
21 |
Pages |
758-766 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In a previous study, it was found that cargo tank operations like cleaning and venting, lead to higher cargo vapor concentrations around the ship’s superstructure. Can wind tunnel experiments confirm these findings? Is there an improvement when using higher outlets at high velocities compared to lower outlets with a low outlet velocity? Is there a relation between relative wind speed and measured concentration? These questions were investigated in the Peutz wind tunnel. By using a tracer gas for the wind tunnel experiments, concentration coefficients have been calculated for various settings. The study shows that using high-velocity outlets is an efficient way to keep concentrations as low as possible. The only exception is for relative wind directions from the bow. In this last case using a manhole as ventilation outlet leads to lower concentrations. With increasing wind speeds the building downwash effect resulted in higher concentration coefficients near the main deck. This study confirms our on-board measurements and suggests the lowering of the ventilation inlet of the accommodation, so that the high-velocity outlet can be used safely at all times. |
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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 ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000388260200015 |
Publication Date |
2016-05-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0948-4280 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
0.838 |
Times cited |
2 |
Open Access |
|
|
Notes |
The authors would like to thank Peutz bv. at Molenhoek, the Netherlands, for providing the wind tunnel facilities and their assistance during the various stages of this research. |
Approved |
Most recent IF: 0.838 |
|
Call Number |
EMAT @ emat @ c:irua:138728 |
Serial |
4326 |
Permanent link to this record |
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Author |
Willhammar, T.; Sentosun, K.; Mourdikoudis, S.; Goris, B.; Kurttepeli, M.; Bercx, M.; Lamoen, D.; Partoens, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Liz-Marzán, L.M.; Bals, S.; Van Tendeloo, G. |
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Title |
Structure and vacancy distribution in copper telluride nanoparticles influence plasmonic activity in the near-infrared |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
|
Volume |
8 |
Issue |
8 |
Pages |
14925 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
Copper chalcogenides find applications in different domains including photonics, photothermal therapy and photovoltaics. CuTe nanocrystals have been proposed as an alternative to noble metal particles for plasmonics. Although it is known that deviations from stoichiometry are a prerequisite for plasmonic activity in the near-infrared, an accurate description of the material and its (optical) properties is hindered by an insufficient understanding of the atomic structure and the influence of defects, especially for materials in their nanocrystalline form. We demonstrate that the structure of Cu1.5±xTe nanocrystals canbe determined using electron diffraction tomography. Real-space high-resolution electron tomography directly reveals the three-dimensional distribution of vacancies in the structure. Through first-principles density functional theory, we furthermore demonstrate that the influence of these vacancies on the optical properties of the nanocrystals is determined. Since our methodology is applicable to a variety of crystalline nanostructured materials, it is expected to provide unique insights concerning structure–property correlations. |
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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 ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000397799700001 |
Publication Date |
2017-03-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
|
ISSN |
2041-1723 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
12.124 |
Times cited |
37 |
Open Access |
OpenAccess |
|
Notes |
The work was financially supported by the European Research Council through an ERC Starting Grant (#335078-COLOURATOMS). T.W. acknowledges the Swedish Research Council for an international postdoc grant. We acknowledge financial support of FWO-Vlaanderen through project G.0216.14N, G.0369.15N and a postdoctoral research grant to B.G. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government–Department EWI. The work was further supported by the Spanish MINECO (MAT2013-45168-R). S.M. thanks the Action ooSupporting Postdoctoral Researchers44 of the Operational Program ‘Education and Lifelong Learning’ (Action’s Beneficiary: General Secretariat for Research and Technology of Greece), which was co-financed by the European Social Fund (ESF) and the Greek State. (ROMEO:green; preprint:; postprint:can ; pdfversion:can); ECAS_Sara |
Approved |
Most recent IF: 12.124 |
|
Call Number |
EMAT @ emat @ c:irua:142203UA @ admin @ c:irua:142203 |
Serial |
4538 |
Permanent link to this record |
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Author |
Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. |
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Title |
Structural and electronic properties of defects at grain boundaries in CuInSe2 |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
Volume |
19 |
Issue |
19 |
Pages |
14770-14780 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect
of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at
the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported. |
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Publisher |
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Place of Publication |
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Editor |
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Language ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000403327200059 |
Publication Date |
2017-05-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.123 |
Times cited |
12 |
Open Access |
OpenAccess |
|
Notes |
We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 4.123 |
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Call Number |
EMAT @ emat @ c:irua:143869 |
Serial |
4577 |
Permanent link to this record |
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Author |
Momot, A.; Amini, M.N.; Reekmans, G.; Lamoen, D.; Partoens, B.; Slocombe, D.R.; Elen, K.; Adriaensens, P.; Hardy, A.; Van Bael, M.K. |
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Title |
A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
Volume |
19 |
Issue |
40 |
Pages |
27866-27877 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
Abstract |
A combined experimental and first-principles study is performed to study the origin of conductivity in
ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a
solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR)
and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial
positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide
evidence for the fact that the formed complex of AlZn and Zni corresponds to the origin of the Knight
shifted peak (KS) we observe in 27Al NMR. As far as we know, the role of this complex has not been
discussed in the literature to date. However, our first-principles calculations show that such a complex is
indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also
address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly
also form Zn clusters, leading to the observed increased conductivity. |
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Place of Publication |
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Language ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000413290500073 |
Publication Date |
2017-10-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.123 |
Times cited |
26 |
Open Access |
OpenAccess |
|
Notes |
We want to thank the Interuniversity Attraction Poles Programme (P7/05) initiated by the Belgian Science Policy Office (BELSPO) for the financial support. We also acknowledge the Research Foundation Flanders (FWO-Vlaanderen) for support via the MULTIMAR WOG project and under project No. G018914. The computational parts were carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules foundation and the Flemish Government (EWI Department). |
Approved |
Most recent IF: 4.123 |
|
Call Number |
EMAT @ emat @c:irua:146878 |
Serial |
4760 |
Permanent link to this record |
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Author |
Bercx, M.; Partoens, B.; Lamoen, D. |
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Title |
Quantitative modeling of secondary electron emission from slow-ion bombardment on semiconductors |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
99 |
Issue |
8 |
Pages |
085413 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
When slow ions incident on a surface are neutralized, the excess potential energy is passed on to an electron inside the surface, leading to emission of secondary electrons. The microscopic description of this process, as
well as the calculation of the secondary electron yield, is a challenging problem due to its complexity as well
as its sensitivity to surface properties. One of the first quantitative descriptions was articulated in the 1950s by
Hagstrum, who based his calculation on a parametrization of the density of states of the material. In this paper, we
present a model for calculating the secondary electron yield, derived from Hagstrum’s initial approach. We use
first-principles density functional theory calculations to acquire the necessary input and introduce the concept of
electron cascades to Hagstrum’s model in order to improve the calculated spectra, as well as remove its reliance
on fitting parameters. We apply our model to He+ and Ne+ ions incident on Ge(111) and Si(111) and obtain
yield spectra that match closely to the experimental results of Hagstrum. |
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Place of Publication |
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Language ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000458367800010 |
Publication Date |
2019-02-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.836 |
Times cited |
5 |
Open Access |
OpenAccess |
|
Notes |
We would like to thank Prof. D. Depla for the useful discussions on the secondary electron yield. Furthermore, we acknowledge financial support of FWO-Vlaanderen through project G.0216.14N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWOVlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 3.836 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:157174 |
Serial |
5154 |
Permanent link to this record |
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Author |
Saniz, R.; Sarmadian, N.; Partoens, B.; Batuk, M.; Hadermann, J.; Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Lamoen, D. |
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Title |
First-principles study of CO and OH adsorption on in-doped ZnO surfaces |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
The journal of physics and chemistry of solids |
Abbreviated Journal |
J Phys Chem Solids |
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Volume |
132 |
Issue |
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Pages |
172-181 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We present a first-principles computational study of CO and OH adsorption on non-polar ZnO (10¯10) surfaces doped with indium. The calculations were performed using a model ZnO slab. The position of the In dopants was varied from deep bulk-like layers to
the surface layers. It was established that the preferential location of the In atoms is at the surface by examining the dependence of
the defect formation energy as well as the surface energy on In location. The adsorption sites on the surface of ZnO and the energy
of adsorption of CO molecules and OH-species were determined in connection to In doping. It was found that OH has higher
bonding energy to the surface than CO. The presence of In atoms at the surface of ZnO is favorable for CO adsorption, resulting
in an elongation of the C-O bond and in charge transfer to the surface. The effect of CO and OH adsorption on the electronic
and conduction properties of surfaces was assessed. We conclude that In-doped ZnO surfaces should present a higher electronic
response upon adsorption of CO. |
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Language ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000472124700023 |
Publication Date |
2019-04-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0022-3697 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.059 |
Times cited |
7 |
Open Access |
Not_Open_Access: Available from 26.04.2021
|
|
Notes |
FWO-Vlaanderen, G0D6515N ; ERA.Net RUS Plus, 096 ; VSC; HPC infrastructure of the University of Antwerp; FWO-Vlaanderen; Flemish Government-department EWI; |
Approved |
Most recent IF: 2.059 |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:159656 |
Serial |
5170 |
Permanent link to this record |
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Author |
Bercx, M.; Slap, L.; Partoens, B.; Lamoen, D. |
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Title |
First-Principles Investigation of the Stability of the Oxygen Framework of Li-Rich Battery Cathodes |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
MRS advances |
Abbreviated Journal |
MRS Adv. |
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Volume |
4 |
Issue |
14 |
Pages |
813-820 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
Lithium-rich layered oxides such as Li<sub>2</sub>MnO<sub>3</sub>have shown great potential as cathodes in Li-ion batteries, mainly because of their large capacities. However, these materials still suffer from structural degradation as the battery is cycled, reducing the average voltage and capacity of the cell. The voltage fade is believed to be related to the migration of transition metals into the lithium layer, linked to the formation of O-O dimers with a short bond length, which in turn is driven by the presence of oxygen holes due to the participation of oxygen in the redox process. We investigate the formation of O-O dimers for partially charged O1-Li<sub>2</sub>MnO<sub>3</sub>using a first-principles density functional theory approach by calculating the reaction energy and kinetic barriers for dimer formation. Next, we perform similar calculations for partially charged O1-Li<sub>2</sub>IrO<sub>3</sub>, a Li-rich material for which the voltage fade was not observed during cycling. When we compare the stability of the oxygen framework, we conclude that the formation of O-O dimers is both thermodynamically and kinetically viable for O1-Li<sub>0.5</sub>MnO<sub>3</sub>. For O1-Li<sub>0.5</sub>IrO<sub>3</sub>, we observe that the oxygen lattice is much more stable, either returning to its original state when perturbed, or resulting in a structure with an O-O dimer that is much higher in energy. This can be explained by the mixed redox process for Li<sub>2</sub>IrO<sub>3</sub>, which is also shown from the calculated magnetic moments. The lack of O-O dimer formation in O1-Li<sub>0.5</sub>IrO<sub>3</sub>provides valuable insight as to why Li<sub>2</sub>IrO<sub>3</sub>does not demonstrate a voltage fade as the battery is cycled, which can be used to design Li-rich battery cathodes with an improved cycling performance. |
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Language ![sorted by Language field, ascending order (up)](img/sort_asc.gif) |
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Wos |
000466846700004 |
Publication Date |
2019-02-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2059-8521 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
3 |
Open Access |
Not_Open_Access: Available from 22.02.2020
|
|
Notes |
We acknowledge the financial support of FWO-Vlaanderen through project G040116N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @UA @ admin @ c:irua:160121 |
Serial |
5179 |
Permanent link to this record |
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Author |
Choudhary, K.; Bercx, M.; Jiang, J.; Pachter, R.; Lamoen, D.; Tavazza, F. |
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Title |
Accelerated Discovery of Efficient Solar Cell Materials Using Quantum and Machine-Learning Methods |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
Volume |
31 |
Issue |
15 |
Pages |
5900-5908 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Solar energy plays an important role in solving serious environmental
problems and meeting the high energy demand. However, the lack of suitable
materials hinders further progress of this technology. Here, we present the largest
inorganic solar cell material search till date using density functional theory (DFT) and
machine-learning approaches. We calculated the spectroscopic limited maximum
efficiency (SLME) using the Tran−Blaha-modified Becke−Johnson potential for 5097
nonmetallic materials and identified 1997 candidates with an SLME higher than 10%,
including 934 candidates with a suitable convex-hull stability and an effective carrier
mass. Screening for two-dimensional-layered cases, we found 58 potential materials
and performed G0W0 calculations on a subset to estimate the prediction uncertainty. As the above DFT methods are still computationally expensive, we developed a high accuracy machine-learning model to prescreen efficient materials and applied it to over a million materials. Our results provide a general framework and universal strategy for the design of high-efficiency solar
cell materials. The data and tools are publicly distributed at: https://www.ctcms.nist.gov/~knc6/JVASP.html, https://www.
ctcms.nist.gov/jarvisml/, https://jarvis.nist.gov/, and https://github.com/usnistgov/jarvis. |
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Wos |
000480826900060 |
Publication Date |
2019-08-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:161814 |
Serial |
5291 |
Permanent link to this record |
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Author |
Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J. |
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Title |
Interstitial defects in the van der Waals gap of Bi2Se3 |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) |
Abbreviated Journal |
Acta Crystallogr B |
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Volume |
75 |
Issue |
4 |
Pages |
717-732 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Bi<sub>2</sub>Se<sub>3</sub>is a thermoelectric material and a topological insulator. It is slightly conducting in its bulk due to the presence of defects and by controlling the defects different physical properties can be fine tuned. However, studies of the defects in this material are often contradicting or inconclusive. Here, the defect structure of Bi<sub>2</sub>Se<sub>3</sub>is studied with a combination of techniques: high-resolution scanning transmission electron microscopy (HR-STEM), high-resolution energy-dispersive X-ray (HR-EDX) spectroscopy, precession electron diffraction tomography (PEDT), X-ray diffraction (XRD) and first-principles calculations using density functional theory (DFT). Based on these results, not only the observed defects are discussed, but also the discrepancies in results or possibilities across the techniques. STEM and EDX revealed interstitial defects with mainly Bi character in an octahedral coordination in the van der Waals gap, independent of the applied sample preparation method (focused ion beam milling or cryo-crushing). The inherent character of these defects is supported by their observation in the structure refinement of the EDT data. Moreover, the occupancy probability of the defects determined by EDT is inversely proportional to their corresponding DFT calculated formation energies. STEM also showed the migration of some atoms across and along the van der Waals gap. The kinetic barriers calculated using DFT suggest that some paths are possible at room temperature, while others are most probably beam induced. |
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Wos |
000480512600024 |
Publication Date |
2019-08-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2052-5206 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.032 |
Times cited |
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Open Access |
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Notes |
University of Antwerp, 31445 ; Acknowledgements We thank Artem M. Abakumov for providing the original Bi2Se3 sample and are also very grateful to Christophe Vandevelde for trying repeatedly to get good single crystal X-ray diffraction data out of each of our failed attempts at making an undeformed single crystal. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 2.032 |
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Call Number |
EMAT @ emat @c:irua:161847 |
Serial |
5295 |
Permanent link to this record |
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Author |
Marchetti, A.; Saniz, R.; Krishnan, D.; Rabbachin, L.; Nuyts, G.; De Meyer, S.; Verbeeck, J.; Janssens, K.; Pelosi, C.; Lamoen, D.; Partoens, B.; De Wael, K. |
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Title |
Unraveling the Role of Lattice Substitutions on the Stabilization of the Intrinsically Unstable Pb2Sb2O7Pyrochlore: Explaining the Lightfastness of Lead Pyroantimonate Artists’ Pigments |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
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Volume |
32 |
Issue |
7 |
Pages |
2863-2873 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
The pyroantimonate pigments Naples yellow and lead tin antimonate yellow are recognized as some of the most stable synthetic yellow pigments in the history of art. However, this exceptional lightfastness is in contrast with experimental evidence suggesting that this class of mixed oxides is of semiconducting nature. In this study the electronic structure and light-induced behavior of the lead pyroantimonate pigments were determined by means of a combined multifaceted analytical and computational approach (photoelectrochemical measurements, UV-vis diffuse reflectance spectroscopy, STEM-EDS, STEM-HAADF, and density functional theory calculations). The results demonstrate both the semiconducting nature and the lightfastness of these pigments. Poor optical absorption and minority carrier mobility are the main properties responsible for the observed stability. In addition, novel fundamental insights into the role played by Na atoms in the stabilization of the otherwise intrinsically unstable Pb2Sb2O7 pyrochlore were obtained. |
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Wos |
000526394000016 |
Publication Date |
2020-04-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.6 |
Times cited |
8 |
Open Access |
OpenAccess |
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Notes |
Universiteit Antwerpen; Belgian Federal Science Policy Office; |
Approved |
Most recent IF: 8.6; 2020 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:168819 |
Serial |
6363 |
Permanent link to this record |
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Author |
Caglak, E.; Govers, K.; Lamoen, D.; Labeau, P.-E.; Verwerft, M. |
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Title |
Atomic scale analysis of defect clustering and predictions of their concentrations in UO2+x |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Nuclear Materials |
Abbreviated Journal |
J Nucl Mater |
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Volume |
541 |
Issue |
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Pages |
152403 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The physical properties of uranium dioxide vary greatly with stoichiometry. Oxidation towards hyperstoichiometric UO2 – UO2+x – might be encountered at various stages of the nuclear fuel cycle if oxidative conditions are met; the impact of stoichiometry changes upon physical properties should therefore be properly assessed to ensure safe and reliable operations. These physical properties are intimately linked to the arrangement of atomic defects in the crystalline structure. The evolution of the defect concentration with environmental parameters – oxygen partial pressure and temperature – were evaluated by means of a point defect model where the reaction energies are derived from atomic-scale simulations. To this end, various configurations and net charge states of oxygen interstitial clusters in UO2 have been calculated. Various methodologies have been tested to determine the optimum cluster configurations and a rigid lattice approach turned out to be the most useful strategy to optimize defect configuration structures. Ultimately, results from the point defect model were discussed and compared to experimental measurements of stoichiometry dependence on oxygen partial pressure and temperature. |
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Wos |
000575165800006 |
Publication Date |
2020-08-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3115 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.1 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
This work is dedicated to the memory of Prof. Alain Dubus, ULB, Bruxelles, Belgium. Financial support from the SCK CEN is gratefully acknowledged. |
Approved |
Most recent IF: 3.1; 2020 IF: 2.048 |
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Call Number |
EMAT @ emat @c:irua:172464 |
Serial |
6402 |
Permanent link to this record |
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Author |
Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. |
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Title |
First-principles study of defects at Σ3 grain boundaries in CuGaSe2 |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Solid State Communications |
Abbreviated Journal |
Solid State Commun |
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Volume |
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Issue |
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Pages |
114263 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
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Abstract |
We present a first-principles computational study of cation–Se 3 (112) grain boundaries in CuGaSe. We discuss the structure of these grain boundaries, as well as the effect of native defects and Na impurities on their electronic properties. The formation energies show that the defects will tend to form preferentially at the grain boundaries, rather than in the grain interiors. We find that in Ga-rich growth conditions Cu vacancies as well as Ga at Cu and Cu at Ga antisites are mainly responsible for having the equilibrium Fermi level pinned toward the middle of the gap, resulting in carrier depletion. The Na at Cu impurity in its +1 charge state contributes to this. In Ga-poor growth conditions, on the other hand, the formation energies of Cu vacancies and Ga at Cu antisites are comparatively too high for any significant influence on carrier density or on the equilibrium Fermi level position. Thus, under these conditions, the Cu at Ga antisites give rise to a -type grain boundary. Also, their formation energy is lower than the formation energy of Na at Cu impurities. Thus, the latter will fail to act as a hole barrier preventing recombination at the grain boundary, in contrast to what occurs in CuInSe grain boundaries. We also discuss the effect of the defects on the electronic properties of bulk CuGaSe, which we assume reflect the properties of the grain interiors. |
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Wos |
000652668500013 |
Publication Date |
2021-03-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0038-1098 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.554 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
Fwo; We acknowledge the financial support of FWO-Vlaanderen, Belgium through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 1.554 |
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Call Number |
EMAT @ emat @c:irua:176544 |
Serial |
6703 |
Permanent link to this record |
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Author |
Leinders, G.; Baldinozzi, G.; Ritter, C.; Saniz, R.; Arts, I.; Lamoen, D.; Verwerft, M. |
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Title |
Charge Localization and Magnetic Correlations in the Refined Structure of U3O7 |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Inorganic Chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
60 |
Issue |
14 |
Pages |
10550-10564 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Atomic arrangements in the mixed-valence oxide U3O7 are refined from high-resolution neutron scattering data. The crystallographic model describes a long-range structural order in a U60O140 primitive cell (space group P42/n) containing distorted cuboctahedral oxygen clusters. By combining experimental data and electronic structure calculations accounting for spin–orbit interactions, we provide robust evidence of an interplay between charge localization and the magnetic moments carried by the uranium atoms. The calculations predict U3O7 to be a semiconducting solid with a band gap of close to 0.32 eV, and a more pronounced charge-transfer insulator behavior as compared to the well-known Mott insulator UO2. Most uranium ions (56 out of 60) occur in 9-fold and 10-fold coordinated environments, surrounding the oxygen clusters, and have a tetravalent (24 out of 60) or pentavalent (32 out of 60) state. The remaining uranium ions (4 out of 60) are not contiguous to the oxygen cuboctahedra and have a very compact, 8-fold coordinated environment with two short (2 × 1.93(3) Å) “oxo-type” bonds. The higher Hirshfeld charge and the diamagnetic character point to a hexavalent state for these four uranium ions. Hence, the valence state distribution corresponds to 24/60 × U(IV) + 32/60 U(V) + 4/60 U(VI). The tetravalent and pentavalent uranium ions are predicted to carry noncollinear magnetic moments (with amplitudes of 1.6 and 0.8 μB, respectively), resulting in canted ferromagnetic order in characteristic layers within the overall fluorite-related structure. |
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Wos |
000675430900049 |
Publication Date |
2021-07-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-1669 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Financial support for this research was partly provided by the Energy Transition Fund of the Belgian FPS Economy (Project SF-CORMOD – Spent Fuel CORrosion MODeling). This work was performed in part using HPC resources from GENCI-IDRIS (Grants 2020-101450 and 2020-101601), and in part by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. GL thanks E. Suard and C. Schreinemachers for assistance during the neutron scattering experiments at the ILL. GB acknowledges V. Petříček for suggestions on using JANA2006. |
Approved |
Most recent IF: 4.857 |
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Call Number |
EMAT @ emat @c:irua:179907 |
Serial |
6801 |
Permanent link to this record |
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Author |
Nematollahi, P.; Barbiellini, B.; Bansil, A.; Lamoen, D.; Qingying, J.; Mukerjee, S.; Neyts, E.C. |
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Title |
Identification of a Robust and Durable FeN4CxCatalyst for ORR in PEM Fuel Cells and the Role of the Fifth Ligand |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
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Issue |
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Pages |
7541-7549 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Although recent studies have advanced the understanding of pyrolyzed
Fe−N−C materials as oxygen reduction reaction (ORR) catalysts, the atomic and
electronic structures of the active sites and their detailed reaction mechanisms still remain unknown. Here, based on first-principles density functional theory (DFT) computations, we discuss the electronic structures of three FeN4 catalytic centers with different local topologies of the surrounding C atoms with a focus on unraveling the mechanism of their ORR activity in acidic electrolytes. Our study brings back a forgotten, synthesized pyridinic Fe−N coordinate to the community’s attention, demonstrating that this catalyst can exhibit excellent activity for promoting direct four-electron ORR through the addition of a fifth ligand such as −NH2, −OH, and −SO4. We also identify sites with good stability properties through the combined use of our DFT calculations and Mössbauer spectroscopy data. |
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Wos |
000823193100001 |
Publication Date |
2022-06-10 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS full record; WoS citing articles |
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Impact Factor |
12.9 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Basic Energy Sciences, DE-FG02-07ER46352 ; Fonds Wetenschappelijk Onderzoek, 1261721N ; Opetus- ja Kulttuuriministeri?; Department of Energy, DE-EE0008416 ; |
Approved |
Most recent IF: 12.9 |
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Call Number |
EMAT @ emat @c:irua:189000 |
Serial |
7073 |
Permanent link to this record |
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Author |
Saniz, R.; Baldinozzi, G.; Arts, I.; Lamoen, D.; Leinders, G.; Verwerft, M. |
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Title |
Charge order, frustration relief, and spin-orbit coupling in U3O8 |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
7 |
Issue |
5 |
Pages |
054410 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Research efforts on the description of the low-temperature magnetic order and electronic properties of U3O8 have been inconclusive so far. Reinterpreting neutron scattering results, we use group representation theory to show that the ground state presents collinear out-of-plane magnetic moments, with antiferromagnetic coupling both in-layer and between layers. Charge order relieves the initial geometric frustration, generating a slightly distorted honeycomb sublattice with Néel-type order. The precise knowledge of the characteristics of this magnetic ground state is then used to explain the fine features of the band gap. In this system, spin-orbit coupling (SOC) is of critical importance, as it strongly affects the electronic structure, narrowing the gap by ∼38%, compared to calculations neglecting SOC. The predicted electronic structure actually explains the salient features of recent optical absorption measurements, further demonstrating the excellent agreement between the calculated ground state properties and experiment. |
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Wos |
001041429800007 |
Publication Date |
2023-05-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Financial support for this research was partly provided by the Energy Transition Fund of the Belgian FPS Economy (Project SF-CORMOD Spent Fuel CORrosion MODeling).Fonds Wetenschappelijk Onderzoek; Vlaams Supercomputer Centrum; Universiteit Antwerpen; Vlaamse regering; |
Approved |
Most recent IF: 3.4; 2023 IF: NA |
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Call Number |
EMAT @ emat @c:irua:197043 |
Serial |
8796 |
Permanent link to this record |
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Author |
Paulus, A.; Hendrickx, M.; Mayda, S.; Batuk, M.; Reekmans, G.; von Holst, M.; Elen, K.; Abakumov, A.M.; Adriaensens, P.; Lamoen, D.; Partoens, B.; Hadermann, J.; Van Bael, M.K.; Hardy, A. |
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Title |
Understanding the Activation of Anionic Redox Chemistry in Ti4+-Substituted Li2MnO3as a Cathode Material for Li-Ion Batteries |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
ACS Appl. Energy Mater. |
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Volume |
6 |
Issue |
13 |
Pages |
6956-6971 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Layered Li-rich oxides, demonstrating both cationic and anionic redox chemistry being used as positive electrodes for Li-ion batteries,have raised interest due to their high specific discharge capacities exceeding 250 mAh/g. However, irreversible structural transformations triggered by anionic redox chemistry result in pronounced voltagefade (i.e., lowering the specific energy by a gradual decay of discharge potential) upon extended galvanostatic cycling. Activating or suppressing oxygen anionic redox through structural stabilization induced by redox-inactivecation substitution is a well-known strategy. However, less emphasishas been put on the correlation between substitution degree and theactivation/suppression of the anionic redox. In this work, Ti4+-substituted Li2MnO3 was synthesizedvia a facile solution-gel method. Ti4+ is selected as adopant as it contains no partially filled d-orbitals. Our study revealedthat the layered “honeycomb-ordered” C2/m structure is preserved when increasing the Ticontent to x = 0.2 in the Li2Mn1-x Ti (x) O-3 solidsolution, as shown by electron diffraction and aberration-correctedscanning transmission electron microscopy. Galvanostatic cycling hintsat a delayed oxygen release, due to an improved reversibility of theanionic redox, during the first 10 charge-discharge cyclesfor the x = 0.2 composition compared to the parentmaterial (x = 0), followed by pronounced oxygen redoxactivity afterward. The latter originates from a low activation energybarrier toward O-O dimer formation and Mn migration in Li2Mn0.8Ti0.2O3, as deducedfrom first-principles molecular dynamics (MD) simulations for the“charged” state. Upon lowering the Ti substitution to x = 0.05, the structural stability was drastically improvedbased on our MD analysis, stressing the importance of carefully optimizingthe substitution degree to achieve the best electrochemical performance. |
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Wos |
001018266700001 |
Publication Date |
2023-07-10 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2574-0962 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.4 |
Times cited |
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Open Access |
Not_Open_Access: Available from 24.12.2023 |
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Notes |
Universiteit Hasselt, AUHL/15/2 – GOH3816N ; Russian Science Foundation, 20-43-01012 ; Fonds Wetenschappelijk Onderzoek, AUHL/15/2 – GOH3816N G040116N ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 6.4; 2023 IF: NA |
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Call Number |
EMAT @ emat @c:irua:198160 |
Serial |
8809 |
Permanent link to this record |
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Author |
Bercx, M.; Mayda, S.; Depla, D.; Partoens, B.; Lamoen, D. |
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Title |
Plasmonic effects in the neutralization of slow ions at a metallic surface |
Type |
A1 Journal Article |
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Year |
2023 |
Publication |
Contributions to Plasma Physics |
Abbreviated Journal |
Contrib. Plasma Phys |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Secondary electron emission is an important process that plays a significant role in several plasma‐related applications. As measuring the secondary electron yield experimentally is very challenging, quantitative modelling of this process to obtain reliable yield data is critical as input for higher‐scale simulations. Here, we build upon our previous work combining density functional theory calculations with a model originally developed by Hagstrum to extend its application to metallic surfaces. As plasmonic effects play a much more important role in the secondary electron emission mechanism for metals, we introduce an approach based on Poisson point processes to include both surface and bulk plasmon excitations to the process. The resulting model is able to reproduce the yield spectra of several available experimental results quite well but requires the introduction of global fitting parameters, which describe the strength of the plasmon interactions. Finally, we use an in‐house developed workflow to calculate the electron yield for a list of elemental surfaces spanning the periodic table to produce an extensive data set for the community and compare our results with more simplified approaches from the literature. |
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Wos |
001067651300001 |
Publication Date |
2023-09-16 |
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ISSN |
0863-1042 |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.6 |
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Open Access |
Not_Open_Access |
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Notes |
We acknowledge the financial support of FWO-Vlaanderen through project G.0216.14N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 1.6; 2023 IF: 1.44 |
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Call Number |
EMAT @ emat @c:irua:200330 |
Serial |
8962 |
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Author |
Claes, J.; Partoens, B.; Lamoen, D. |
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Title |
Decoupled DFT-1/2 method for defect excitation energies |
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A1 Journal Article |
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Year |
2023 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys. Rev. B |
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Volume |
108 |
Issue |
12 |
Pages |
125306 |
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Keywords |
A1 Journal Article; Condensed Matter Theory (CMT) ; |
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Abstract |
The DFT-1/2 method is a band-gap correction with GW precision at a density functional theory (DFT) computational cost. The method was also extended to correct the gap between defect levels, allowing for the calculation of optical transitions. However, this method fails when the atomic character of the occupied and unoccupied defect levels is similar as we illustrate by two examples, the tetrahedral hydrogen interstitial and the negatively charged vacancy in diamond. We solve this problem by decoupling the effect of the occupied and unoccupied defect levels and call this the decoupled DFT-1/2 method for defects. |
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001089302800003 |
Publication Date |
2023-09-25 |
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ISSN |
2469-9950 |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.7 |
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Not_Open_Access |
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Notes |
This work was supported by the FWO (Research Foundation-Flanders), Project No. G0D1721N. This work was performed in part using HPC resources from the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government department EWI (Economie, Wetenschap & Innovatie). |
Approved |
Most recent IF: 3.7; 2023 IF: 3.836 |
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Call Number |
CMT @ cmt @c:irua:201287 |
Serial |
8976 |
Permanent link to this record |