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Author Stafford, B.H.; Sieger, M.; Ottolinger, R.; Meledin, A.; Strickland, N.M.; Wimbush, S.C.; Van Tendeloo, G.; Huehne, R.; Schultz, L.
Title Tilted BaHfO3 nanorod artificial pinning centres in REBCO films on inclined substrate deposited-MgO coated conductor templates Type A1 Journal article
Year 2017 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 30 Issue 5 Pages 055002
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We grow BaHfO3 (BHO) nanorods in REBa2Cu3O7-x (REBCO, RE: Gd or Y) thin films on metal tapes coated with the inclined substrate deposited (ISD)-MgO template by both electron beam physical vapour deposition and pulsed laser deposition. In both cases the nanorods are inclined by an angle of 21 degrees-29 degrees with respect to the sample surface normal as a consequence of the tilted growth of the REBCO film resulting from the ISD-MgO layer. We present angular critical current density (J(c)) anisotropy as well as field- and temperature-dependant J(c) data of the BHO nanorod-containing GdBCO films demonstrating an increase in J(c) over a wide range of temperatures between 30 and 77 K and magnetic fields up to 8 T. In addition, we show that the angle of the peak in the J(c) anisotropy curve resulting from the nanorods is dependent both on temperature and magnetic field. The largest J(c) enhancement from the addition of the nanorods was found to occur at 30 K, 3 T, resulting in a J(c) of 3.0 MA cm(-2).
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000398860300001 Publication Date 2017-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 6 Open Access Not_Open_Access
Notes ; The authors would like to thank Anh Tu Bohn and other colleagues at THEVA Dunnschichtechnik GmbH for technical assistance and helpful discussion and R Nast for assistance with sample patterning. We also acknowledge partial support from EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7/2007-2013) under Grant Agreement n. 280432. ; Approved Most recent IF: 2.878
Call Number UA @ lucian @ c:irua:143641 Serial 4694
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Author Denneulin, T.; Rouvière, J.L.; Béché, A.; Py, M.; Barnes, J.P.; Rochat, N.; Hartmann, J.M.; Cooper, D.
Title The reduction of the substitutional C content in annealed Si/SiGeC superlattices studied by dark-field electron holography Type A1 Journal article
Year 2011 Publication Semiconductor science and technology Abbreviated Journal Semicond Sci Tech
Volume 26 Issue 12 Pages 1-10
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Si/Si(1 − x − y)GexCy superlattices are used in the construction of new microelectronic architectures such as multichannel transistors. The introduction of carbon in SiGe allows for compensation of the strain and to avoid plastic relaxation. However, the formation of incoherent β-SiC clusters during annealing limits the processability of SiGeC. This precipitation leads to a modification of the strain in the alloy due to the reduction of the substitutional carbon content. Here, we investigated the strain in annealed Si/Si0.744Ge0.244C0.012 superlattices grown by reduced pressure chemical vapour deposition using dark-field electron holography. The variation of the substitutional C content was calculated by correlating the results with finite-element simulations. The obtained values were then compared with Fourier-transformed infrared spectrometry measurements. It was shown that after annealing for 2 min at 1050 °C carbon no longer has any influence on strain in the superlattice, which behaves like pure SiGe. However, a significant proportion of substitutional C atoms remain in a third-nearest neighbour (3nn) configuration. It was deduced that the influence of 3nn C on strain is negligible and that only isolated atoms have a significant contribution. It was also proposed that the 3nn configuration is an intermediary step during the formation of SiC clusters.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000300151300010 Publication Date 2011-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0268-1242 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.305 Times cited Open Access
Notes Approved Most recent IF: 2.305; 2011 IF: 1.723
Call Number UA @ lucian @ c:irua:136427 Serial 4508
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Author Charkin, D.O.; Plokhikh, I.V.; Kazakov, S.M.; Kalmykov, S.N.; Akinfiev, V.S.; Gorbachev, A.V.; Batuk, M.; Abakumov, A.M.; Teterin, Y.A.; Maslakov, K.I.; Teterin, A.Y.; Ivanov, K.E.
Title Synthesis and structural characterization of a novel Sillén – Aurivillius bismuth oxyhalide, PbBi3VO7.5Cl, and its derivatives Type A1 Journal article
Year 2018 Publication Solid state sciences Abbreviated Journal Solid State Sci
Volume 75 Issue Pages 27-33
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new Sillen – Aurivillius family of layered bismuth oxyhalides has been designed and successfully constructed on the basis of PbBiO2X(X = halogen) synthetic perites and g-form of Bi2VO5.5 solid elec- trolyte. This demonstrates, for the first time, the ability of the latter to serve as a building block in construction of mixed-layer structures. The parent compound PbBi3VO7.5-dCl (d = 0.05) has been investigated by powder XRD, TEM, XPS methods and magnetic susceptibility measurements. An unexpected but important condition for the formation of the mixed-layer structure is partial (ca. 5%) reduction of VV into VIV which probably suppresses competitive formation of apatite-like Pb – Bi vanadates. This reduction also stabilizes the g polymorphic form of Bi2VO5.5 not only in the intergrowth structure, but in Bi2V1-xMxO5.5-y (M – Nb, Sb) solid solutions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000418566200005 Publication Date 2017-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1293-2558 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.811 Times cited 1 Open Access Not_Open_Access
Notes The work was partially supported by M.V. Lomonosov Moscow State University Program of Development and Russian Science Foundation under Grant No.14-13-00738. We also thank Dr. K.V. Zakharov (MSU) for the magnetic measurements of the PbBi3- VO7.5Cl sample. Approved Most recent IF: 1.811
Call Number EMAT @ emat @c:irua:147239 Serial 4769
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Author Garud, S.; Gampa, N.; Allen, T.G.; Kotipalli, R.; Flandre, D.; Batuk, M.; Hadermann, J.; Meuris, M.; Poortmans, J.; Smets, A.; Vermang, B.
Title Surface passivation of CIGS solar cells using gallium oxide Type A1 Journal article
Year 2018 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume 215 Issue 7 Pages 1700826
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract This work proposes gallium oxide grown by plasma-enhanced atomic layer deposition, as a surface passivation material at the CdS buffer interface of Cu(In,Ga)Se-2 (CIGS) solar cells. In preliminary experiments, a metal-insulator-semiconductor (MIS) structure is used to compare aluminium oxide, gallium oxide, and hafnium oxide as passivation layers at the CIGS-CdS interface. The findings suggest that gallium oxide on CIGS may show a density of positive charges and qualitatively, the least interface trap density. Subsequent solar cell results with an estimated 0.5nm passivation layer show an substantial absolute improvement of 56mV in open-circuit voltage (V-OC), 1mAcm(-2) in short-circuit current density (J(SC)), and 2.6% in overall efficiency as compared to a reference (with the reference showing 8.5% under AM 1.5G).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430128500015 Publication Date 2018-02-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.775 Times cited 8 Open Access Not_Open_Access
Notes ; The work published in this paper was supported by the European Research Council (ERC) under the Union's Horizon 2020 research and innovation programme (grant agreement No 715027). The authors would also like to thank Dr. Marcel Simor (Solliance) for the CIGS layer fabrication and Prof. Johan Lauwaert (Universtiy of Ghent) for his guidance on DLTS measurements. ; Approved Most recent IF: 1.775
Call Number UA @ lucian @ c:irua:150761 Serial 4981
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Author Gkanatsiou, A.; Lioutas, C.B.; Frangis, N.; Polychroniadis, E.K.; Prystawko, P.; Leszczynski, M.; Altantzis, T.; Van Tendeloo, G.
Title Influence of 4H-SiC substrate miscut on the epitaxy and microstructure of AlGaN/GaN heterostructures Type A1 Journal article
Year 2019 Publication Materials science in semiconductor processing Abbreviated Journal Mat Sci Semicon Proc
Volume 91 Issue Pages 159-166
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract AlGaN/GaN heterostructures were grown on “on-axis” and 2° off (0001) 4H-SiC substrates by metalorganic vapor phase epitaxy (MOVPE). Structural characterization was performed by transmission electron microscopy. The dislocation density, being greater in the on-axis case, is gradually reduced in the GaN layer and is forming

dislocation loops in the lower region. Steps aligned along [11̅00] in the off-axis case give rise to simultaneous defect formation. In the on-axis case, an almost zero density of steps is observed, with the main origin of defects probably being the orientation mismatch at the grain boundaries between the small not fully coalesced AlN grains. V-shaped formations are observed in the AlN nucleation layer, but are more frequent in the off-axis case, probably enhanced by the presence of steps. These V-shaped formations are completely overgrown by the GaN layer, during the subsequent deposition, presenting AlGaN areas in the walls of the defect, indicating an interdiffusion between the layers. Finally, at the AlGaN/GaN heterostructure surface in the on-axis case, V-shapes are observed, with the AlN spacer and AlGaN (21% Al) thickness on relaxed GaN exceeding the critical thickness for relaxation. On the other hand, no relaxation in the form of V-shape creation is observed in the off-axis case, probably due to the smaller AlGaN thickness (less than 21% Al). The AlN spacer layer, grown in between the heterostructure, presents a uniform thickness and clear interfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000454537700022 Publication Date 2018-11-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1369-8001 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.359 Times cited 1 Open Access Not_Open_Access
Notes Funding: This work was supported by the IKY Fellowships of Excellence for Postgraduate Studies in Greece-SIEMENS Program; the Greek General Secretariat for Research and Technology, contract SAE 013/8–2009SE 01380012; and the JU ENIAC Project LAST POWER Large Area silicon carbide Substrates and heteroepitaxial GaN for POWER device applications [grant number 120218]. Also part of the research leading to these results has received funding from the European Union Seventh Framework Program under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative–I3). T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a post-doctoral grant. Approved Most recent IF: 2.359
Call Number EMAT @ emat @UA @ admin @ c:irua:156200 Serial 5149
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Author Bueken, B.; Van Velthoven, N.; Willhammar, T.; Stassin, T.; Stassen, I.; Keen, D.A.; Baron, G.V.; Denayer, J.F.M.; Ameloot, R.; Bals, S.; De Vos, D.; Bennett, T.D.
Title Gel-based morphological design of zirconium metal-organic frameworks Type A1 Journal article
Year 2017 Publication Chemical science Abbreviated Journal Chem Sci
Volume 8 Issue 8 Pages 3939-3948
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The ability of metal-organic frameworks (MOFs) to gelate under specific synthetic conditions opens up new opportunities in the preparation and shaping of hierarchically porous MOF monoliths, which could be directly implemented for catalytic and adsorptive applications. In this work, we present the first examples of xero-or aerogel monoliths consisting solely of nanoparticles of several prototypical Zr4+-based MOFs: UiO-66-X (X – H, NH2, NO2, (OH)(2)), UiO-67, MOF-801, MOF-808 and NU-1000. High reactant and water concentrations during synthesis were observed to induce the formation of gels, which were converted to monolithic materials by drying in air or supercritical CO2. Electron microscopy, combined with N-2 physisorption experiments, was used to show that irregular nanoparticle packing leads to pure MOF monoliths with hierarchical pore systems, featuring both intraparticle micropores and interparticle mesopores. Finally, UiO-66 gels were shaped into monolithic spheres of 600 mm diameter using an oil-drop method, creating promising candidates for packed-bed catalytic or adsorptive applications, where hierarchical pore systems can greatly mitigate mass transfer limitations.
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Corporate Author Thesis
Publisher Royal Society of Chemistry Place of Publication Cambridge Editor
Language Wos 000400553000077 Publication Date 2017-03-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-6520 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.668 Times cited 168 Open Access OpenAccess
Notes ; B. B., T. S. and I. S. acknowledge the FWO Flanders (doctoral and post-doctoral grants). T. W. acknowledges a post-doctoral grant from the Swedish Research Council. T. D. B. acknowledges the Royal Society (University Research Fellowship) and Trinity Hall (University of Cambridge) for funding. S. B. and D. D. V. are grateful for funding by Belspo (IAP 7/05 P6/27) and by the FWO Flanders. D. D. V. further acknowledges funding from the European Research Council (project H-CCAT). S. B. acknowledges financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). The authors acknowledge Arnau Carne and Shuhei Furukawa for assistance with supercritical CO<INF>2</INF> extraction, and Charles Ghesquiere for assistance in synthesis. ; Ecas_Sara Approved Most recent IF: 8.668
Call Number UA @ lucian @ c:irua:152643UA @ admin @ c:irua:152643 Serial 5143
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Author Korneychuk, S.; Guzzinati, G.; Verbeeck, J.
Title Measurement of the Indirect Band Gap of Diamond with EELS in STEM Type A1 Journal article
Year 2018 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume 215 Issue 22 Pages 1800318
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this work, a simple method to measure the indirect band gap of diamond with electron energy loss spectroscopy (EELS) in transmission electron microscopy (TEM) is showed. The authors discuss the momentum space resolution achievable with EELS and the possibility of deliberately selecting specific transitions of interest. Based on a simple 2 parabolic band model of the band structure, the authors extend our predictions from the direct band gap case discussed in previous work, to the case of an indirect band gap. Finally, the authors point out the emerging possibility to partly reconstruct the band structure with EELS exploiting our simplified model of inelastic scattering and support it with experiments on diamond.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000450818100004 Publication Date 2018-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.775 Times cited 6 Open Access Not_Open_Access
Notes S.K. and J.V. acknowledge funding from the “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint” of the University of Antwerp. Financial support via the Methusalem “NANO” network is acknowledged. G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint”; Methusalem “NANO” network; Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO); Hercules fund from the Flemish Government; Approved Most recent IF: 1.775
Call Number EMAT @ emat @UA @ admin @ c:irua:155402 Serial 5138
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Author Van Goethem, C.; Verbeke, R.; Pfanmoeller, M.; Koschine, T.; Dickmann, M.; Timpel-Lindner, T.; Egger, W.; Bals, S.; Vankelecom, I.F.J.
Title The role of MOFs in Thin-Film Nanocomposite (TFN) membranes Type A1 Journal article
Year 2018 Publication Journal of membrane science Abbreviated Journal J Membrane Sci
Volume 563 Issue 563 Pages 938-948
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Incorporation of MOFs in interfacially polymerized Thin-Film Nanocomposite (TFN) membranes has widely been shown to result in increased membrane performance. However, the exact functioning of these membranes is poorly understood as large variability in permeance increase, filler incorporation and rejection changes can be observed in literature. The synthesis and functioning of TFN membranes (herein exemplified by ZIF-8 filled polyamide (PA) membranes prepared via the EFP method) was investigated via targeted membrane synthesis and thorough characterization via STEM-EDX, XRD and PALS. It is hypothesized that the acid generated during the interfacial polymerization (IP) at least partially degrades the crystalline, acid-sensitive ZIF-8 and that this influences the membrane formation (through so-called secondary effects, i.e. not strictly linked to the pore morphology of the MOF). Nanoscale HAADF-STEM imaging and STEM-EDX Zn-mapping revealed no ZIF-8 particles but rather the presence of randomly shaped regions with elevated Zn-content. Also XRD failed to show the presence of crystalline areas in the composite PA films. As the addition of the acid-quenching TEA led to an increase in the diffraction signal observed in XRD, the role of the acid was confirmed. The separate addition of dissolved Zn2+ to the synthesis of regular TFC membranes showed an increase in permeance while losing some salt retention, similar to observations regularly made for TFN membranes. While the addition of a porous material to a TFC membrane is a straightforward concept, all obtained results indicate that the synthesis and performance of such composite membranes is often more complex than commonly accepted.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000441897200099 Publication Date 2018-06-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0376-7388 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.035 Times cited 84 Open Access OpenAccess
Notes ; C.V.G. and R.V. kindly acknowledge respectively the Flemish Agency for Innovation through Science and Technology (IWT) (IWT, 141697) and the Flemish Fund for Scientific Research (FWO, 1500917N) for a PhD scholarship. The authors kindly acknowledge funding from KU Leuven through C16/17/005 and from the Belgian Federal Government through IAP 6/27 Functional Supramolecular systems. S.B. and M.P. acknowledge financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOM). M.P. acknowledges funding from the European Union (ESTEEM2, No. 312483) and the HEiKA centre FunTECH-3D (Ministry of Science, Research and Art Baden-Wurttemberg, AZ: 33-753-30-20/3/3). The MLZ-Garching is kindly acknowledged for providing access to the NEPOMUC facilities (project no 11541). ; ecas_sara Approved Most recent IF: 6.035
Call Number UA @ lucian @ c:irua:153618UA @ admin @ c:irua:153618 Serial 5132
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Author Pahlke, P.; Sieger, M.; Ottolinger, R.; Lao, M.; Eisterer, M.; Meledin, A.; Van Tendeloo, G.; Haenisch, J.; Holzapfel, B.; Schultz, L.; Nielsch, K.; Huehne, R.
Title Influence of artificial pinning centers on structural and superconducting properties of thick YBCO films on ABAD-YSZ templates Type A1 Journal article
Year 2018 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 31 Issue 4 Pages 044007
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Recent efforts in the development of YBa2Cu3O7-x (YBCO) coated conductors are devoted to the increase of the critical current I-c in magnetic fields. This is typically realized by growing thicker YBCO layers as well as by the incorporation of artificial pinning centers. We studied the growth of doped YBCO layers with a thickness of up to 7 mu m using pulsed laser deposition with a growth rate of about 1.2 nm s(-1). Industrially fabricated ion-beam textured YSZ templates based on metal tapes were used as substrates for this study. The incorporation of BaHfO3 (BHO) or Ba2Y(Nb0.5Ta0.5)O-6 (BYNTO) secondary phase additions leads to a denser microstructure compared to undoped films. A purely c-axis-oriented YBCO growth is preserved up to a thickness of about 4 mu m, whereas misoriented texture components were observed in thicker films. The critical temperature is slightly reduced compared to undoped films and independent of film thickness. The critical current density J(c) of the BHO- and BYNTO-doped YBCO layers is lower at 77 K and self-field compared to pure YBCO layers; however, I-c increases up to a thickness of 5 mu m. A comparison between films with a thickness of 1.3 mu m revealed that the anisotropy of the critical current density J(c)(theta) strongly depends on the incorporated pinning centers. Whereas BHO nanorods lead to a strong B vertical bar vertical bar c-axis peak, the overall anisotropy is significantly reduced by the incorporation of BYNTO forming a mixture of short c-axis-oriented nanorods and small (a-b)-oriented platelets. As a result, the J(c) values of the doped films outperform the undoped samples at higher fields and lower temperatures for most magnetic field directions.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000442196400001 Publication Date 2018-02-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 9 Open Access OpenAccess
Notes ; The authors acknowledge financial support from EURO-TAPES, a collaborative project funded by the European Union's Seventh Framework Programme (FP7/ 2007-2013) under Grant Agreement no. 280432. We thank A Usoskin (Bruker HTS GmbH, Germany) for the provision of buffered templates, and M Bianchetti, A Kursumovic and J L Mac-Manus-Driscoll (University of Cambridge, UK) for the supply of BYNTO targets. The authors also gratefully acknowledge the technical assistance of J Scheiter, M Kuhnel, U Besold (IFW) and R Nast (KIT). ; Approved Most recent IF: 2.878
Call Number UA @ lucian @ c:irua:153775 Serial 5108
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Author Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q.
Title Study of the Q′ (Q)-phase precipitation in Al–Mg–Si–Cu alloys by quantification of atomic-resolution transmission electron microscopy images and atom probe tomography Type A1 Journal article
Year 2019 Publication Journal of materials science Abbreviated Journal J Mater Sci
Volume 54 Issue 10 Pages 7943-7952
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The precipitation mechanism of the Q phase in Al-Mg-Si-Cu alloys has long been the subject of ambiguity and debate since its metastable phase (Q 0) has the same crystal structure and similar lattice parameters as its equilibrium counterparts. In the present work, the evolution of the Q 0 (Q) phase during aging is studied by combination of quantitative atomic-resolution scanning transmission electron microscopy and atom probe tomography. It was found that the transformation from the Q 0 to the Q phase involves changes of the occupancy of Al atoms in atomic columns of the Q 0 (Q) phase. The Al atoms incorporated in the Cu, Si and Mg columns are gradually released into the Al matrix, while mixing between Cu and Si atoms occurs in the Si columns. This transformation process is mainly attributed to the low lattice misfit of the equilibrium Q phase. Besides, the formation of various compositions of the Q phase is due to the different occupancy in the atomic columns of the Q phase. The occupancy changes in the columns of the Q phase are kinetically controlled and are strongly influenced by the alloy composition and aging temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000460069500043 Publication Date 2019-02-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2461 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.599 Times cited 1 Open Access Not_Open_Access
Notes Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing, cstc2017zdcy-zdzxX0006 ; Fundamental Research Funds for the Central Universities of China, 2018CDGFCL0002 106112017CDJQJ308822 ; Belgian National Fund for Scientific Research; the National Natural Science Foundation of China, 51871035 ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant No. cstc2017zdcyzdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDGFCL0002), the National Natural Science Foundation of China (Grant No. 51871035) and the Foundation for Innovative Research Groups J Mater Sci National Natural Science Foundation of China (Grant No. 51421001). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). Approved Most recent IF: 2.599
Call Number EMAT @ emat @UA @ admin @ c:irua:158112 Serial 5158
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Author Van Velthoven, N.; Waitschat, S.; Chavan, S.M.; Liu, P.; Smolders, S.; Vercammen, J.; Bueken, B.; Bals, S.; Lillerud, K.P.; Stock, N.; De Vos, D.E.
Title Single-site metal-organic framework catalysts for the oxidative coupling of arenes via C-H/C-H activation Type A1 Journal article
Year 2019 Publication Chemical science Abbreviated Journal Chem Sci
Volume 10 Issue 10 Pages 3616-3622
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract C-H activation reactions are generally associated with relatively low turnover numbers (TONs) and high catalyst concentrations due to a combination of low catalyst stability and activity, highlighting the need for recyclable heterogeneous catalysts with stable single-atom active sites. In this work, several palladium loaded metal-organic frameworks (MOFs) were tested as single-site catalysts for the oxidative coupling of arenes (e.g. o-xylene) via C-H/C-H activation. Isolation of the palladium active sites on the MOF supports reduced Pd(0) aggregate formation and thus catalyst deactivation, resulting in higher turnover numbers (TONs) compared to the homogeneous benchmark reaction. Notably, a threefold higher TON could be achieved for palladium loaded MOF-808 due to increased catalyst stability and the heterogeneous catalyst could efficiently be reused, resulting in a cumulative TON of 1218 after three runs. Additionally, the palladium single-atom active sites on MOF-808 were successfully identified by Fourier transform infrared (FTIR) and extended X-ray absorption fine structure (EXAFS) spectroscopy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000463759100017 Publication Date 2019-02-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-6520 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.668 Times cited 68 Open Access OpenAccess
Notes ; The research leading to these results has received funding from the NMBP-01-2016 Program of the European Union's Horizon 2020 Framework Program H2020/2014-2020/under grant agreement no. [720996]. N. V. V., S. S., J. V., B. B. and D. E. D. V. thank the FWO for funding (SB, Aspirant and postdoctoral grants). The electron microscopy work was supported by FWO funding G038116. D. E. D. V. is grateful for KU Leuven support in the frame of the CASAS Metusalem project and a C3 type project. The XAS experiments were performed on beamline BM26A at the European Synchrotron Radiation Facility (ESRF), Grenoble, France. We are grateful to D. Banerjee at the ESRF for providing assistance in using beamline BM26A. Johnson Matthey and S. Bennett are gratefully acknowledged for providing Smopex-102. ; Approved Most recent IF: 8.668
Call Number UA @ admin @ c:irua:159403 Serial 5259
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Author Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J.
Title Interstitial defects in the van der Waals gap of Bi2Se3 Type A1 Journal article
Year 2019 Publication Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) Abbreviated Journal Acta Crystallogr B
Volume 75 Issue 4 Pages 717-732
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000480512600024 Publication Date 2019-08-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2052-5206 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.032 Times cited Open Access
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
Call Number EMAT @ emat @c:irua:161847 Serial 5295
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Author Cremers, V.; Rampelberg, G.; Baert, K.; Abrahami, S.; Claes, N.; de Oliveira, T.M.; Terryn, H.; Bals, S.; Dendooven, J.; Detavernier, C.
Title Corrosion protection of Cu by atomic layer deposition Type A1 Journal article
Year 2019 Publication Journal of vacuum science and technology: A: vacuum surfaces and films Abbreviated Journal J Vac Sci Technol A
Volume 37 Issue 37 Pages 060902
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Atomic layer deposition (ALD) is a vapor phase technique that is able to deposit uniform, conformal thin films with an excellent thickness control at the atomic scale. 18 nm thick Al2O3 and TiO2 coatings were deposited conformaly and pinhole-free onto micrometer-sized Cu powder, using trimethylaluminum and tetrakis(dimethylamido)titanium(IV), respectively, as a precursor and de-ionized water as a reactant. The capability of the ALD coating to protect the Cu powder against corrosion was investigated. Therefore, the stability of the coatings was studied in solutions with different pH in the range of 0–14, and in situ raman spectroscopy was used to detect the emergence of corrosion products of Cu as an indication that the protective coating starts to fail. Both ALD coatings provide good protection at standard pH values in the range of 5–7. In general, the TiO2 coating shows a better barrier protection against corrosion than the Al2O3 coating. However, for the most extreme pH conditions, pH 0 and pH 14, the TiO2 coating starts also to degrade.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000517925800003 Publication Date 2019-09-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0734-2101 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.374 Times cited 7 Open Access OpenAccess
Notes The authors acknowledge financial support from the Strategic Initiative Materials in Flanders (SIM, SBO-FUNC project) and the Special Research Fund BOF of Ghent University (No. GOA 01G01513). J.D. acknowledges the Research Foundation Flanders (FWO-Vlaanderen) for a postdoctoral fellowship. Approved Most recent IF: 1.374
Call Number EMAT @ emat @c:irua:162640 Serial 5361
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Author Zhao, L.; Ding, L.; Soete, J.; Idrissi, H.; Kerckhofs, G.; Simar, A.
Title Fostering crack deviation via local internal stresses in Al/NiTi composites and its correlation with fracture toughness Type A1 Journal article
Year 2019 Publication Composites: part A: applied science and manufacturing Abbreviated Journal Compos Part A-Appl S
Volume 126 Issue 126 Pages 105617
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In the framework of metal matrix composites, a research gap exists regarding tailoring damage mechanisms. The present work aims at developing an Al/NiTi composite incorporating internal stresses in the vicinity of reinforcements. The composite is manufactured by friction stir processing which allows a homogenous NiTi distribution and a good Al/NiTi interface bonding. The internal stresses are introduced via shape memory effect of the embedded NiTi particles. The induced internal strain field is confirmed by digital image correlation and the corresponding stress field is evaluated by finite element simulation. It is found that the damage mechanism is modified in the presence of internal stresses. The consequent enhancement of fracture toughness arises by the fact that the internal stresses foster discrete damages shifted from the fracture ligament line. These damages release the stress concentration at the main crack tip and lead to a deviated crack path when coalescing to accommodate fracture propagation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000489350600025 Publication Date 2019-09-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-835x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.075 Times cited Open Access
Notes ; This research work has been exclusively supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement no 716678). The X-ray computed,tomography facilities of the Department of Materials Engineering of the KU Leuven are financed by the Hercules Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). The authors acknowledge Professor F. Delannay from UCLouvain for fruitful discussions. ; Approved Most recent IF: 4.075
Call Number UA @ admin @ c:irua:163706 Serial 5387
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Author Lumbeeck, G.; Delvaux, A.; Idrissi, H.; Proost, J.; Schryvers, D.
Title Analysis of internal stress build-up during deposition of nanocrystalline Ni thin films using transmission electron microscopy Type A1 Journal article
Year 2020 Publication Thin solid films : an international journal on the science and technology of thin and thick films Abbreviated Journal Thin Solid Films
Volume 707 Issue Pages 138076
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ni thin films sputter-deposited at room temperature with varying Ar pressures were investigated with automated crystal orientation mapping in a transmission electron microscope to uncover the mechanisms controlling the internal stress build-up recorded in-situ during deposition. Large grains were found to induce behaviour similar to a stress-free nucleation layer. The measurements of grain size in most of the Ni thin films are in agreement with the island coalescence model. Low internal stress was observed at low Ar pressure and was explained by the presence of large grains. Relaxation of high internal stress was also noticed at the highest Ar pressure, which was attributed to a decrease of Σ3 twin boundary density due to a low deposition rate. The results provide insightful information to better understand the relationship between structural boundaries and the evolution of internal stress upon deposition of thin films.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000539312200011 Publication Date 2020-05-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes This work was supported by the Hercules Foundation [Grant No. AUHA13009], the Flemish Research Fund (FWO) [Grant No. G.0365.15N], and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. Thin film deposition has been realised as part of the WallonHY project, funded by the Public Service of Wallonia – Department of Energy and Sustainable Building. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:169708 Serial 6370
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Author Celentano, G.; Rizzo, F.; Augieri, A.; Mancini, A.; Pinto, V.; Rufoloni, A.; Vannozzi, A.; MacManus-Driscoll, J.L.; Feighan, J.; Kursumovic, A.; Meledin, A.; Mayer, J.; Van Tendeloo, G.
Title YBa2Cu3O7−xfilms with Ba2Y(Nb,Ta)O6nanoinclusions for high-field applications Type A1 Journal article
Year 2020 Publication Superconductor Science & Technology Abbreviated Journal Supercond Sci Tech
Volume 33 Issue 4 Pages 044010
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The structural and transport properties of YBa2Cu3O7−x films grown by pulsed laser deposition with mixed 2.5 mol% Ba2YTaO6 (BYTO) and 2.5 mol% Ba2YNbO6 (BYNO) double-perovskite secondary phases are investigated in an extended film growth rate, R = 0.02–1.8 nm s−1. The effect of R on the film microstructure analyzed by TEM techniques shows an evolution from sparse and straight to denser, thinner and splayed continuous columns, with mixed BYNO + BYTO (BYNTO) composition, as R increases from 0.02 nm s−1 to 1.2 nm s−1. This microstructure results in very efficient flux pinning at 77 K, leading to a remarkable improvement in the critical current density (J c) behaviour, with the maximum pinning force density F p(Max) = 13.5 GN m−3 and the irreversibility field in excess of 11 T. In this range, the magnetic field values at which the F p is maximized varies from 1 T to 5 T, being related to the BYNTO columnar density. The film deposited when R = 0.3 nm s−1 exhibits the best performances over the whole temperature and magnetic field ranges, achieving F p(Max) = 900 GN m−3 at 10 K and 12 T. At higher rates, R > 1.2 nm s−1, BYNTO columns show a meandering nature and are prone to form short nanorods. In addition, in the YBCO film matrix a more disordered structure with a high density of short stacking faults is observed. From the analysis of the F p(H, T) curves it emerges that in films deposited at the high R limit, the vortex pinning is no longer dominated by BYNTO columnar defects, but by a new mechanism showing the typical temperature scaling law. Even though this microstructure produces a limited improvement at 77 K, it exhibits a strong J c improvement at lower temperature with F p = 700 GN m−3 at 10 K, 12 T and 900 GN m−3 at 4.2 K, 18 T.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000525650500001 Publication Date 2020-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.6 Times cited Open Access OpenAccess
Notes This work was partially financially supported by EUROTAPES, a collaborative project funded by the European Commission’s Seventh Framework Program (FP7/2007–2013) under Grant Agreement No. 280432. This work has been partially carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom programme 2014-2018 and 2019-2020 under grant agreement N° 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3 (Nano-engineered YBCO Superconducting Tapes for High Field Applications, NESTApp). G. C. acknowledges the support of Michele De Angelis for XRD measurements and calculations. Approved Most recent IF: 3.6; 2020 IF: 2.878
Call Number UA @ lucian @c:irua:168582 Serial 6394
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Author Gropp, C.; Canossa, S.; Wuttke, S.; Gándara, F.; Li, Q.; Gagliardi, L.; Yaghi, O.M.
Title Standard Practices of Reticular Chemistry Type A1 Journal article
Year 2020 Publication Acs Central Science Abbreviated Journal Acs Central Sci
Volume 6 Issue 8 Pages 1255-1273
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Since 1995 when the first of metal−organic frameworks was crystallized with the strong bond approach, where metal ions are joined by charged organic linkers exemplified by carboxylates, followed by proof of their porosity in 1998 and ultrahigh porosity in 1999, a revolution in the development of their chemistry has ensued. This is being reinforced by the discovery of two- and three-dimensional covalent organic frameworks in 2005 and 2007. Currently, the chemistry of such porous, crystalline frameworks is collectively referred to as reticular chemistry, which is being practiced in over 100 countries. The involvement of researchers from various backgrounds and fields, and the vast scope of this chemistry and its societal applications, necessitate articulating the “Standard Practices of Reticular Chemistry”.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000566668400005 Publication Date 2020-08-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2374-7943 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 18.2 Times cited Open Access OpenAccess
Notes S.C. acknowledges the Research Foundation Flanders (FWO) for supporting his research (Project 12ZV120N). Approved Most recent IF: 18.2; 2020 IF: 7.481
Call Number EMAT @ emat @c:irua:172057 Serial 6423
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Author Vishwakarma, M.; Agrawal, K.; Hadermann, J.; Mehta, B.R.
Title Investigating the effect of sulphurization on volatility of compositions in Cu-poor and Sn-rich CZTS thin films Type A1 Journal article
Year 2020 Publication Applied Surface Science Abbreviated Journal Appl Surf Sci
Volume 507 Issue Pages 145043
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In the present work, the Cu-poor and Sn-rich CZTS thin films were prepared in order to study the volatility of Sn with respect to other components. Thin film compositions were kept intentionally Sn-rich to understand the behaviour of loss and segregation of Sn during sulphurization. The homogeneous composition distribution in precursor thin films turns heterogeneous with a change in morphology after sulphurization. The inability of identifying nanoscale secondary phases in CZTS thin film by conventional analytical techniques such as XRD and Raman, can be fulfilled by employing HAADF-STEM analysis. XPS and HAADF-STEM analyses provide the quantification of nanoscale secondary phases across the thin film and surface, respectively. The volatility of Sn was revealed in the form of segregation in the middle layer of CZTS cross-sectional lamella rather than loss to annealing atmosphere. It was observed that among the cations of CZTS, Sn segregates more than Cu, while Zn segregates least. The nanoscale spurious phases were observed to vary across different regions in the sulphurized CZTS sample. The reactive annealing lead to grain growth and formation of grain boundary features in the CZTS thin films, where annealing significantly modifies the potential difference and band bending at grain boundaries with respect to intra-grains.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000520021200053 Publication Date 2019-12-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited 4 Open Access OpenAccess
Notes ; Authors acknowledges support provided by DST, India in the forms of InSOL project. We also acknowledge Dr. Indrani Mishra for XPS measurements and DST-FIST Raman facility for Raman measurements. Manoj Vishwakarma acknowledges IIT Delhi, New Delhi, India for MHRD fellowship. Prof. B.R. Mehta acknowledges the support of the Schlumberger chair professorship. ; Approved Most recent IF: 6.7; 2020 IF: 3.387
Call Number UA @ admin @ c:irua:168603 Serial 6552
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Author Volykhov, A.A.; Frolov, A.S.; Neudachina, V.S.; Vladimirova, N.V.; Gerber, E.; Callaert, C.; Hadermann, J.; Khmelevsky, N.O.; Knop-Gericke, A.; Sanchez-Barriga, J.; Yashina, L.V.
Title Impact of ordering on the reactivity of mixed crystals of topological insulators with anion substitution: Bi₂SeTe₂ and Sb₂SeTe₂ Type A1 Journal article
Year 2021 Publication Applied Surface Science Abbreviated Journal Appl Surf Sci
Volume 541 Issue Pages 148490
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Three-dimensional topological insulators are exotic materials with unique properties. Tetradymite type binary chalcogenides of bismuth and antimony, as well as their mixed crystals, belong to prototypical TIs. Potential device applications of these materials require in-depth knowledge of their stability in the ambient atmosphere and other media maintained during their processing. Here we investigated the reactivity of mixed crystals with anion substitution, Bi-2(Se1-xTex)(3) and Sb2(Se1-xTex)(3), towards molecular oxygen using both in situ and ex situ X-ray photoelectron spectroscopy. The results indicate that, in contrast to cation substitution, partial substitution of tellurium by selenium atoms leads to anomalously high surface reactivity, which even exceeds that of the most reactive binary constituent. We attribute this effect to anion ordering that essentially modifies the bond geometry, especially the respective bond angles as modeled by DFT.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000608492900003 Publication Date 2020-11-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.387 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 3.387
Call Number UA @ admin @ c:irua:176067 Serial 6728
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Author Jannis, D.; Müller-Caspary, K.; Béché, A.; Verbeeck, J.
Title Coincidence Detection of EELS and EDX Spectral Events in the Electron Microscope Type A1 Journal article
Year 2021 Publication Applied Sciences-Basel Abbreviated Journal Appl Sci-Basel
Volume 11 Issue 19 Pages 9058
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Recent advances in the development of electron and X-ray detectors have opened up the possibility to detect single events from which its time of arrival can be determined with nanosecond resolution. This allows observing time correlations between electrons and X-rays in the transmission electron microscope. In this work, a novel setup is described which measures individual events using a silicon drift detector and digital pulse processor for the X-rays and a Timepix3 detector for the electrons. This setup enables recording time correlation between both event streams while at the same time preserving the complete conventional electron energy loss (EELS) and energy dispersive X-ray (EDX) signal. We show that the added coincidence information improves the sensitivity for detecting trace elements in a matrix as compared to conventional EELS and EDX. Furthermore, the method allows the determination of the collection efficiencies without the use of a reference sample and can subtract the background signal for EELS and EDX without any prior knowledge of the background shape and without pre-edge fitting region. We discuss limitations in time resolution arising due to specificities of the silicon drift detector and discuss ways to further improve this aspect.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000710160300001 Publication Date 2021-09-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2076-3417 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.679 Times cited 9 Open Access OpenAccess
Notes Fonds Wetenschappelijk Onderzoek, G042920 ; Horizon 2020 Framework Programme, 101017720 ; Helmholtz-Fonds, VH-NG-1317 ; Approved Most recent IF: 1.679
Call Number EMAT @ emat @c:irua:183336 Serial 6821
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Author Zhao, H.; Li, C.-F.; Hu, Z.-Y.; Liu, J.; Li, Y.; Hu, J.; Van Tendeloo, G.; Chen, L.-H.; Su, B.-L.
Title Size effect of bifunctional gold in hierarchical titanium oxide-gold-cadmium sulfide with slow photon effect for unprecedented visible-light hydrogen production Type A1 Journal article
Year 2021 Publication Journal Of Colloid And Interface Science Abbreviated Journal J Colloid Interf Sci
Volume 604 Issue Pages 131-139
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Gold nanoparticles (Au NPs) with surface plasmonic resonance (SPR) effect and excellent internal electron transfer ability have widely been combined with semiconductors for photocatalysis. However, the in-depth effects of Au NPs in multicomponent photocatalysts have not been completely understood. Herein, ternary titanium oxide-gold-cadmium sulfide (TiO2-Au-CdS, TAC) photocatalysts, based on hierarchical TiO2 inverse opal photonic crystal structure with different Au NPs sizes have been designed to reveal the SPR effect and internal electron transfer of Au NPs in the presence of slow photon effect. It appears that the SPR effect and internal electron transfer ability of Au NPs, depending on their sizes, play a synergistic effect on the photocatalytic enhancement. The ternary TAC-10 photocatalyst with – 10 nm Au NPs demonstrates an unprecedented hydrogen evolution rate of 47.6 mmolh-1g 1 under visible-light, demonstrating- 48% enhancement comparing to the sample without slow photon effect. In particular, a 9.83% apparent quantum yield under 450 nm monochromatic light is achieved for TAC-10. A model is proposed and finite-difference time-domain (FDTD) simulations reveal the size influence of Au NPs in ternary TAC photocatalysts. This work suggests that the rational design of bifunctional Au NPs coupling with slow photon effect could largely promote hydrogen production from visible-light driven water splitting. (c) 2021 Elsevier Inc. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000704428600004 Publication Date 2021-07-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9797 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.233 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.233
Call Number UA @ admin @ c:irua:182531 Serial 6886
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Author Meng, X.; Chen, S.; Peng, H.; Bai, H.; Zhang, S.; Su, X.; Tan, G.; Van Tendeloo, G.; Sun, Z.; Zhang, Q.; Tang, X.; Wu, J.
Title Ferroelectric engineering : enhanced thermoelectric performance by local structural heterogeneity Type A1 Journal article
Year 2022 Publication Science China : materials Abbreviated Journal Sci China Mater
Volume Issue Pages
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Although traditional ferroelectric materials are usually dielectric and nonconductive, GeTe is a typical ferroelectric semiconductor, possessing both ferroelectric and semiconducting properties. GeTe is also a widely studied thermoelectric material, whose performance has been optimized by doping with various elements. However, the impact of the ferroelectric domains on the thermoelectric properties remains unclear due to the difficulty to directly observe the ferroelectric domains and their evolutions under actual working conditions where the material is exposed to high temperatures and electric currents. Herein, based on in-situ investigations of the ferroelectric domains and domain walls in both pure and Sb-doped GeTe crystals, we have been able to analyze the dynamic evolution of the ferroelectric domains and domain walls, exposed to an electric field and temperature. Local structural heterogeneities and nano-sized ferroelectric domains are generated due to the interplay of the Sb3+ dopant and the Ge-vacancies, leading to the increased number of charged domain walls and a much improved thermoelectric performance. This work reveals the fundamental mechanism of ferroelectric thermoelectrics and provides insights into the decoupling of previously interdependent properties such as thermo-power and electrical conductivity.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000749973500001 Publication Date 2022-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2095-8226; 2199-4501 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.1 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 8.1
Call Number UA @ admin @ c:irua:186429 Serial 6959
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Author Missen, O.P.; Mills, S.J.; Canossa, S.; Hadermann, J.; Nenert, G.; Weil, M.; Libowitzky, E.; Housley, R.M.; Artner, W.; Kampf, A.R.; Rumsey, M.S.; Spratt, J.; Momma, K.; Dunstan, M.A.
Title Polytypism in mcalpineite : a study of natural and synthetic Cu₃TeO₆ Type A1 Journal article
Year 2022 Publication Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) Abbreviated Journal Acta Crystallogr B
Volume 78 Issue 1 Pages
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Synthetic and naturally occurring forms of tricopper orthotellurate, (Cu3TeO6)-Te-II-O-IV (the mineral mcalpineite) have been investigated by 3D electron diffraction (3D ED), X-ray powder diffraction (XRPD), Raman and infrared (IR) spectroscopic measurements. As a result of the diffraction analyses, (Cu3TeO6)-Te-II-O-IV is shown to occur in two polytypes. The higher-symmetric (Cu3TeO6)-Te-II-O-IV-1C polytype is cubic, space group 1a (3) over bar, with a = 9.537 (1) angstrom and V = 867.4 (3) angstrom(3) as reported in previous studies. The 1C polytype is a well characterized structure consisting of alternating layers of (CuO6)-O-II octahedra and both (CuO6)-O-II and (TeO6)-O-VI octahedra in a patchwork arrangement. The structure of the lower-symmetric orthorhombic (Cu3TeO6)-Te-II-O-IV-2O polytype was determined for the first time in this study by 3D ED and verified by Rietveld refinement. The 2O polytype crystallizes in space group Pcca, with a = 9.745 (3) angstrom, b = 9.749 (2) angstrom, c = 9.771 (2) angstrom and V = 928.3 (4) angstrom(3) . High-precision XRPD data were also collected on (Cu3TeO6)-Te-II-O-IV-2O to verify the lower-symmetric structure by performing a Rietveld refinement. The resultant structure is identical to that determined by 3D ED, with unit-cell parameters a = 9.56157 (19) angstrom, b = 9.55853 (11) angstrom, c = 9.62891 (15) angstrom and V = 880.03 (2) angstrom(3) . The lower symmetry of the 2O polytype is a consequence of a different cation ordering arrangement, which involves the movement of every second (CuO6)-O-II and (TeO6)-O-VI octahedral layer by (1/4, 1/4, 0), leading to an offset of (TeO6)-O-VI and (CuO6)-O-II octahedra in every second layer giving an ABAB* stacking arrangement. Syntheses of (Cu3TeO6)-Te-II-O-IV showed that low-temperature (473 K) hydrothermal conditions generally produce the 2O polytype. XRPD measurements in combination with Raman spectroscopic analysis showed that most natural mcalpineite is the orthorhombic 2O polytype. Both XRPD and Raman spectroscopy measurements may be used to differentiate between the two polytypes of (Cu3TeO6)-Te-II-O-IV. In Raman spectroscopy, (Cu3TeO6)-Te-II-O-IV-1C has a single strong band around 730 cm(-1), whereas (Cu3TeO6)-Te-II-O-IV-2O shows a broad double maximum with bands centred around 692 and 742 cm(-1).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000752899700003 Publication Date 2022-01-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2052-5206 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.9 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 1.9
Call Number UA @ admin @ c:irua:186529 Serial 6962
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Author Idrissi, H.; Carrez, P.; Cordier, P.
Title On amorphization as a deformation mechanism under high stresses Type A1 Journal article
Year 2022 Publication Current opinion in solid state and materials science Abbreviated Journal Curr Opin Solid St M
Volume 26 Issue 1 Pages 100976-17
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this paper we review the work related to amorphization under mechanical stress. Beyond pressure, we highlight the role of deviatoric or shear stresses. We show that the most recent works make amorphization appear as a deformation mechanism in its own right, in particular under extreme conditions (shocks, deformations under high stresses, high strain-rates).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000779433300002 Publication Date 2022-01-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-0286 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 11
Call Number UA @ admin @ c:irua:188014 Serial 7064
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Author Li, C.-F.; Chen, L.-D.; Wu, L.; Liu, Y.; Hu, Z.-Y.; Cui, W.-J.; Dong, W.-D.; Liu, X.; Yu, W.-B.; Li, Y.; Van Tendeloo, G.; Su, B.-L.
Title Directly revealing the structure-property correlation in Na+-doped cathode materials Type A1 Journal article
Year 2023 Publication Applied surface science Abbreviated Journal
Volume 612 Issue Pages 155810-10
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The introduction of Na+ is considered as an effective way to improve the performance of Ni-rich cathode materials. However, the direct structure-property correlation for Na+ doped NCM-based cathode materials remain unclear, due to the difficulty of local and accurate structural characterization for light elements such as Li and Na. Moreover, there is the complexity of the modeling for the whole Li ion battery (LIB) system. To tackle the above-mentioned issues, we prepared Na+-doped LiNi0.6Co0.2Mn0.2O2 (Na-NCM622) material. The crystal structure change and the lattice distortion with picometers precision of the Na+-doped material is revealed by Cs-corrected scanning transmission electron microscopy (STEM). Density functional theory (DFT) and the recently proposed electrochemical model, i.e., modified Planck-Nernst-Poisson coupled Frumkin-Butler-Volmer (MPNP-FBV), has been applied to reveal correlations between the activation energy and the charge transfer resistance at multiscale. It is shown that Na+ doping can reduce the activation energy barrier from. G = 1.10 eV to 1.05 eV, resulting in a reduction of the interfacial resistance from 297 O to 134 Omega. Consequently, the Na-NCM622 cathode delivers a superior capacity retention of 90.8 % (159 mAh.g(-1)) after 100 cycles compared to the pristine NCM622 (67.5 %, 108 mAh.g(-1)). Our results demonstrate that the kinetics of Li+ diffusion and the electrochemical reaction can be enhanced by Na+ doping the cathode material.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000892940300001 Publication Date 2022-11-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 6.7; 2023 IF: 3.387
Call Number UA @ admin @ c:irua:192758 Serial 7296
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Author Benedet, M.; Andrea Rizzi, G.; Gasparotto, A.; Gauquelin, N.; Orekhov, A.; Verbeeck, J.; Maccato, C.; Barreca, D.
Title Functionalization of graphitic carbon nitride systems by cobalt and cobalt-iron oxides boosts solar water oxidation performances Type A1 Journal article
Year 2023 Publication Applied surface science Abbreviated Journal
Volume 618 Issue Pages 156652
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The ever-increasing energy demand from the world population has made the intensive use of fossil fuels an overarching threat to global environment and human health. An appealing alternative is offered by sunlight-assisted photoelectrochemical water splitting to yield carbon-free hydrogen fuel, but kinetic limitations associated to the oxygen evolution reaction (OER) render the development of cost-effective, eco-friendly and stable electrocatalysts an imperative issue. In the present work, OER catalysts based on graphitic carbon nitride (g-C3N4) were deposited on conducting glass substrates by a simple decantation procedure, followed by functionalization with low amounts of nanostructured CoO and CoFe2O4 by radio frequency (RF)-sputtering, and final annealing under inert atmosphere. A combination of advanced characterization tools was used to investigate the interplay between material features and electrochemical performances. The obtained results highlighted the formation of a p-n junction for the g-C3N4-CoO system, whereas a Z-scheme junction accounted for the remarkable performance enhancement yielded by g-C3N4-CoFe2O4. The intimate contact between the system components also afforded an improved electrocatalyst stability in comparison to various bare and functionalized g-C3N4-based systems. These findings emphasize the importance of tailoring g-C3N4 chemico-physical properties through the dispersion of complementary catalysts to fully exploit its applicative potential.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000950654300001 Publication Date 2023-02-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited 11 Open Access OpenAccess
Notes The authors gratefully acknowledge financial support from CNR (Progetti di Ricerca @CNR – avviso 2020 – ASSIST), Padova University (P-DiSC#04BIRD2020-UNIPD EUREKA, DOR 2020–2022), AMGA Foundation (NYMPHEA project), INSTM Consortium (INSTM21PDGASPAROTTO – NANOMAT, INSTM21PDBARMAC – ATENA) and the European Union's Horizon 2020 research and innovation program under grant agreement No 823717 – ESTEEM3. The FWO-Hercules fund G0H4316N 'Direct electron detector for soft matter TEM' is also acknowledged. Many thanks are due to Prof. Luca Gavioli (Università Cattolica del Sacro Cuore, Brescia, Italy) and Dr. Riccardo Lorenzin (Department of Chemical Sciences, Padova University, Italy) for their invaluable technical support.; esteem3reported; esteem3TA Approved Most recent IF: 6.7; 2023 IF: 3.387
Call Number EMAT @ emat @c:irua:196150 Serial 7376
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Author Herregods, S.J.F.; Mertens, M.; Van Havenbergh, K.; Van Tendeloo, G.; Cool, P.; Buekenhoudt, A.; Meynen, V.
Title Controlling pore size and uniformity of mesoporous titania by early stage low temperature stabilization Type A1 Journal article
Year 2013 Publication Journal of colloid and interface science Abbreviated Journal J Colloid Interf Sci
Volume 391 Issue Pages 36-44
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract The control of the formation process during and after self-assembly is of utmost importance to achieve well structured, controlled template-assisted mesoporous titania materials with the desired properties for various applications via the evaporation induced self-assembly method (EISA). The present paper reports on the large influence of the thermal stabilization and successive template removal on the pore structure of a mesostructured TiO2 material using the diblock copolymer Brij 58 as surfactant. A controlled thermal stabilization (temperature and duration) allows one to tailor the final pore size and uniformity much more precise by influencing the self-assembly of the template. Moreover, also the successive thermal template removal needs to be controlled in order to avoid a structural collapse. N2-sorption, TGA, TEM, FT-Raman spectroscopy, and small angle wide angle XRD have been used to follow the crystal growth and mesostructure organization after thermal stabilization and after thermal template removal, revealing its effect on the final pore structure.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000312039000006 Publication Date 2012-10-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9797; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.233 Times cited 12 Open Access
Notes Approved Most recent IF: 4.233; 2013 IF: 3.552
Call Number UA @ lucian @ c:irua:101757 Serial 506
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Author Lebedev, O.I.; Van Tendeloo, G.; Collart, O.; Cool, P.; Vansant, E.F.
Title Structure and microstructure of nanoscale mesoporous silica spheres Type A1 Journal article
Year 2004 Publication Solid state sciences Abbreviated Journal Solid State Sci
Volume 6 Issue Pages 489-498
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000221604500011 Publication Date 2004-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1293-2558; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.811 Times cited 42 Open Access
Notes Pai/Iuap P5/01 Approved Most recent IF: 1.811; 2004 IF: 1.598
Call Number UA @ lucian @ c:irua:46262 Serial 3289
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Author Van Everbroeck, T.; Wu, J.; Arenas-Esteban, D.; Ciocarlan, R.-G.; Mertens, M.; Bals, S.; Dujardin, C.; Granger, P.; Seftel, E.M.; Cool, P.
Title ZnAl layered double hydroxide based catalysts (with Cu, Mn, Ti) used as noble metal-free three-way catalysts Type A1 Journal article
Year 2022 Publication Applied clay science Abbreviated Journal Appl Clay Sci
Volume 217 Issue Pages 106390
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000795870100004 Publication Date 2022-01-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-1317 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.6 Times cited 6 Open Access OpenAccess
Notes The authors acknowledge financial support by theEuropean Union’s Horizon 2020 Project Partial-PGMs (H2020-NMP-686086). R-G C. and P.C. acknowledge the FWO-Flanders (project no. G038215N) for financial support. S⋅B and D.A.E thank the financial support of the European Research Council (ERC-CoG-2019 815128). The authors are grateful to Johnson Matthey, UK, for supplying the commercial benchmark catalysts; realnano; sygmaSB Approved Most recent IF: 5.6
Call Number EMAT @ emat @c:irua:186956 Serial 6955
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Author Van Dijck, J.G.; Mampuys, P.; Ching, H.Y.V.; Krishnan, D.; Baert, K.; Hauffman, T.; Verbeeck, J.; Van Doorslaer, S.; Maes, B.U.W.; Dorbec, M.; Buekenhoudt, A.; Meynen, V.
Title Synthesis – properties correlation and the unexpected role of the titania support on the Grignard surface modification Type A1 Journal article
Year 2020 Publication Applied Surface Science Abbreviated Journal Appl Surf Sci
Volume 527 Issue Pages 146851-17
Keywords (up) A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY); Applied Electrochemistry & Catalysis (ELCAT)
Abstract While the impact of reaction conditions on surface modification with Grignard reactants has been studied for silica supports, such information is absent for metal oxides like titania. Differences between modified titania and silica are observed, making it paramount to explore the reaction mechanism. A detailed study on the impact of the reaction conditions is reported, with a focus on the chain length of the alkyl Grignard reactant, its concentration, the reaction time and temperature, and the type of titania support. While the increase in the chain length reduces the amount of organic groups on the surface, the concentration, time and temperature show little/no influence on the modification degree. However, the type of titania support used and the percentage of amorphous phase present has a significant impact on the amount of grafted groups. Even though the temperature and concentration show no clear impact on the modification degree, they can cause changes in the surface hydroxyl population, which are thus not linked to the modification degree. Furthermore, the titania support is reduced during functionalization. This reduction dependents on the reaction temperature, the titania support and the chain length of the Grignard reactant. Similarly, this reduction is not linked to the modification degree.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000564205300003 Publication Date 2020-06-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited 5 Open Access OpenAccess
Notes ; The FWO (Fonds Wetenschappelijk Onderzoek) is gratefully acknowledged for the VITO-FWO grant of fellow Jeroen G. Van Dijck (11W9416N) and the financial support granted in project GO12712N. The E.U. is acknowledged for H.Y. Vincent Ching's H2020-MSCA-IF (grant number 792946, iSPY). Dileep Krishnan and Johan Verbeeck acknowledge funding from GOA project “solarpaint” of the University of Antwerp. ; Approved Most recent IF: 6.7; 2020 IF: 3.387
Call Number UA @ admin @ c:irua:169722 Serial 6712
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