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Author Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q. pdf  doi
openurl 
  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 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 (down) EMAT @ emat @UA @ admin @ c:irua:158112 Serial 5158  
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Author Charalampopoulou, E.; Delville, R.; Verwerft, M.; Lambrinou, K.; Schryvers, D. pdf  url
doi  openurl
  Title Transmission electron microscopy study of complex oxide scales on DIN 1.4970 steel exposed to liquid Pb-Bi eutectic Type A1 Journal article
  Year 2019 Publication Corrosion science Abbreviated Journal Corrosion Science  
  Volume 147 Issue Pages 22-31  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The deployment of Gen-IV lead-cooled fast reactors requires a good compatibility between the selected structural/cladding steels and the inherently corrosive heavy liquid metal coolant. An effective liquid metal corrosion mitigation strategy involves the in-situ steel passivation in contact with the oxygen-containing Pb-alloy coolant. Transmission electron microscopy was used in this work to study the multi-layered oxide scales forming on an austenitic stainless steel fuel cladding exposed to oxygen-containing (CO ≈ 10−6 mass%) static liquid leadbismuth eutectic (LBE) for 1000 h between 400 and 500 °C. The oxide scale constituents were analyzed, including the intertwined phases comprising the innermost biphasic layer.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000456902100003 Publication Date 2018-10-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0010938X ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 5 Open Access OpenAccess  
  Notes The authors would like to thank J. Joris for the technical support during corrosion testing and J. Lim for the manufacturing and calibration of the oxygen sensors and oxygen pumps used in this work. E. Charalampopoulou personally thanks H. Heidari, S. Pourbabak, A. Orekhov (EMAT) and N. Cautaerts (EMAT, SCK•CEN), for their valuable help with the training of the FEI Tecnai Osiris S/TEM and Jeol 3000 S/ TEM, respectively, as well as S. Van den Broeck (EMAT), J. Pakarinen (SCK•CEN) and W. Van Renterghem (SCK•CEN) for FIB sample preparation. Moreover, the authors gratefully acknowledge the funding provided in the framework of the ongoing development of the MYRRHA irradiation facility. The research leading to these results falls within the framework of the European Energy Research Alliance Joint Programme on Nuclear Materials (EERA JPNM). Approved Most recent IF: NA  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:157541 Serial 5164  
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Author Cautaerts, N.; Delville, R.; Schryvers, D. pdf  doi
openurl 
  Title ALPHABETA: a dedicated open-source tool for calculating TEM stage tilt angles Type A1 Journal article
  Year 2019 Publication Journal of microscopy Abbreviated Journal J Microsc-Oxford  
  Volume 273 Issue 3 Pages 189-198  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
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  Language Wos 000458426100004 Publication Date 2018-12-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-2720 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.692 Times cited 2 Open Access Not_Open_Access  
  Notes ENGIE Ph.D. sponsorship, 2015-AC-007 – BSUEZ6900 ; Approved Most recent IF: 1.692  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:157474 Serial 5163  
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Author Montero-Sistiaga, M.L.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D.; Vanmeensel, K. pdf  url
doi  openurl
  Title Microstructure and mechanical properties of Hastelloy X produced by HP-SLM (high power selective laser melting) Type A1 Journal article
  Year 2019 Publication Materials & design Abbreviated Journal Mater Design  
  Volume 165 Issue Pages 107598  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract In order to increase the production rate during selective laser melting (SLM), a high power laser with a large beam diameter is used to build fully dense Hastelloy X parts. Compared to SLM with a low power and small diameter beam, the productivity was increased from 6 mm3/s to 16 mm3/s, i.e. 2.6 times faster. Besides the productivity benefit, the influence of the use of a high power laser on the rapid solidification microstructure and concomitant material properties is highlighted. The current paper compares the microstructure and tensile properties of Hastelloy X built with low and high power lasers. The use of a high power laser results in wider and shallower melt pools inducing an enhanced morphological and crystallographic texture along the building direction (BD). In addition, the increased heat input results in coarser sub-grains or high density dislocation walls for samples processed with a high power laser. Additionally, the influence of hot isostatic pressing (HIP) as a post-processing technique was evaluated. After HIP, the tensile fracture strain increased as compared to the strain in the as-built state and helped in obtaining competitive mechanical properties as compared to conventionally processed Hastelloy X parts.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000458259300020 Publication Date 2019-01-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0264-1275 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.364 Times cited 15 Open Access OpenAccess  
  Notes This research was supported by the ENGIE Research and Technology Division. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine. S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. Approved Most recent IF: 4.364  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:157469 Serial 5176  
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Author Fatermans, J.; Van Aert, S.; den Dekker, A.J. url  doi
openurl 
  Title The maximum a posteriori probability rule for atom column detection from HAADF STEM images Type A1 Journal article
  Year 2019 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 201 Issue Pages 81-91  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract Recently, the maximum a posteriori (MAP) probability rule has been proposed as an objective and quantitative method to detect atom columns and even single atoms from high-resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images. The method combines statistical parameter estimation and model-order selection using a Bayesian framework and has been shown to be especially useful for the analysis of the structure of beam-sensitive nanomaterials. In order to avoid beam damage, images of such materials are usually acquired using a limited incoming electron dose resulting in a low contrast-to-noise ratio (CNR) which makes visual inspection unreliable. This creates a need for an objective and quantitative approach. The present paper describes the methodology of the MAP probability rule, gives its step-by-step derivation and discusses its algorithmic implementation for atom column detection. In addition, simulation results are presented showing that the performance of the MAP probability rule to detect the correct number of atomic columns from HAADF STEM images is superior to that of other model-order selection criteria, including the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC). Moreover, the MAP probability rule is used as a tool to evaluate the relation between STEM image quality measures and atom detectability resulting in the introduction of the so-called integrated CNR (ICNR) as a new image quality measure that better correlates with atom detectability than conventional measures such as signal-to-noise ratio (SNR) and CNR.  
  Address  
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  Language Wos 000466343800009 Publication Date 2019-02-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 1 Open Access OpenAccess  
  Notes The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (No. W.O.010.16N, No. G.0368.15N, No. G.0502.18N). This project has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (Grant Agreement No. 770887). Approved Most recent IF: 2.843  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:157176 Serial 5153  
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Author Van Aert, S.; De Backer, A.; Jones, L.; Martinez, G.T.; Béché, A.; Nellist, P.D. pdf  url
doi  openurl
  Title Control of Knock-On Damage for 3D Atomic Scale Quantification of Nanostructures: Making Every Electron Count in Scanning Transmission Electron Microscopy Type A1 Journal article
  Year 2019 Publication Physical review letters Abbreviated Journal Phys Rev Lett  
  Volume 122 Issue 6 Pages 066101  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Understanding nanostructures down to the atomic level is the key to optimizing the design of advancedmaterials with revolutionary novel properties. This requires characterization methods capable of quantifying the three-dimensional (3D) atomic structure with the highest possible precision. A successful approach to reach this goal is to count the number of atoms in each atomic column from 2D annular dark field scanning transmission electron microscopy images. To count atoms with single atom sensitivity, a minimum electron dose has been shown to be necessary, while on the other hand beam damage, induced by the high energy electrons, puts a limit on the tolerable dose. An important challenge is therefore to develop experimental strategies to optimize the electron dose by balancing atom-counting fidelity vs the risk of knock-on damage. To achieve this goal, a statistical framework combined with physics-based modeling of the dose-dependent processes is here proposed and experimentally verified. This model enables an investigator to theoretically predict, in advance of an experimental measurement, the optimal electron dose resulting in an unambiguous quantification of nanostructures in their native state with the highest attainable precision.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000458824200008 Publication Date 2019-02-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9007 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.462 Times cited 3 Open Access OpenAccess  
  Notes This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (WO.010.16N, G.0934.17N, G.0502.18N, G.0267.18N), and a grant to A. D. B. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement No. 312483— ESTEEM2 (Integrated Infrastructure Initiative-I3) and the UK EPSRC (Grant No. EP/M010708/1). Approved Most recent IF: 8.462  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:157175 Serial 5156  
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Author Bercx, M.; Partoens, B.; Lamoen, D. pdf  url
doi  openurl
  Title Quantitative modeling of secondary electron emission from slow-ion bombardment on semiconductors Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 99 Issue 8 Pages 085413  
  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.
 
  Address  
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  Language Wos 000458367800010 Publication Date 2019-02-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  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  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:157174 Serial 5154  
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Author Miotti Bettanini, A.; Ding, L.; Mithieux, J.-D.; Parrens, C.; Idrissi, H.; Schryvers, D.; Delannay, L.; Pardoen, T.; Jacques, P.J. pdf  url
doi  openurl
  Title Influence of M23C6 dissolution on the kinetics of ferrite to austenite transformation in Fe-11Cr-0.06C stainless steel Type A1 Journal article
  Year 2019 Publication Materials & design Abbreviated Journal Mater Design  
  Volume 162 Issue Pages 362-374  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The design of high-strength martensitic stainless steels requires an accurate control over the stability of undesired phases, like carbides and ferrite, which can hamper strength and ductility. Here, the ferrite to austenite transformation in Fe-11Cr-0.06C has been studied with a combined experimental-modelling approach. Experimental observations of the austenization process indicate that austenite growth proceeds in multiple steps, each one characterized by a different transformation rate. DICTRA based modelling reveals that the dissolution of the M23C6 Cr-rich carbides leads to Cr partitioning between austenite and parent phases, which controls the rate of transformation through (i) a soft-impingement effect and (ii) consequent stabilization of the ferrite, which remains untransformed inside chromium-enriched-zones even after prolonged austenization stage. Slow heating rate and smaller initial particle sizes allow the design of ferrite-free microstructure.  
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  Language Wos 000454128400036 Publication Date 2018-12-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0264-1275 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.364 Times cited 3 Open Access OpenAccess  
  Notes The authors thank Professor Anne-Francoise Gourgues-Lorenzon and Helene Godin, Ecole Nationale Superiore des Mines de Paris (MINES ParisTech) for their fruitful discussions. AMB thanks Stijn Van den broek (Universiteit Antwerpen) for the skillful preparation of TEM samples with FIB. The financial support of CBMM (Companhia Brasileira de Metalurgia e Mineracao) is gratefully acknowledged. L. Delannay is mandated by the FNRS-Belgium. Computational resources have been provided by the supercomputing facilities of the UCLouvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en Federation Wallonie Bruxelles (CÉCI) funded by the Fond de la Recherche Scientifique de Belgique (F.R.S.-FNRS) under convention 2.5020.11.; Cbmm; F.r.s.-fnrs, 2.5020.11 ; Approved Most recent IF: 4.364  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:156721 Serial 5161  
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Author Zhang, Y.; Bals, S.; Van Tendeloo, G. pdf  url
doi  openurl
  Title Understanding CeO2-Based Nanostructures through Advanced Electron Microscopy in 2D and 3D Type A1 Journal article
  Year 2019 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char  
  Volume 36 Issue 36 Pages 1800287  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Engineering morphology and size of CeO2-based nanostructures on a (sub)nanometer scale will greatly influence their performance; this is because of their high oxygen storage capacity and unique redox properties, which allow faster switching of the oxidation state between Ce4+ and Ce3+. Although tremendous research has been carried out on the shapecontrolled synthesis of CeO2, the characterization of these nanostructures at the atomic scale remains a major challenge and the origin of debate. The rapid developments of aberration-corrected transmission electron microscopy (AC-TEM) have pushed the resolution below 1 Å, both in TEM and in scanning transmission electron microscopy (STEM) mode. At present, not only morphology and structure, but also composition and electronic structure can be analyzed at an atomic scale, even in 3D. This review summarizes recent significant achievements using TEM/ STEM and associated spectroscopic techniques to study CeO2-based nanostructures and related catalytic phenomena. Recent results have shed light on the understanding of the different mechanisms. The potential and limitations, including future needs of various techniques, are discussed with recommendations to facilitate further developments of new and highly efficient CeO2-based nanostructures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000455414600012 Publication Date 2018-10-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0934-0866 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.474 Times cited 22 Open Access OpenAccess  
  Notes Y.Z. acknowledges financial support from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska- Curie grant agreement no. 665501 through a FWO [PEGASUS]2 Marie Skłodowska-Curie fellowship (12U4917N). S.B. acknowledges funding from the European Research Council, ERC grant no. 335078-Colouratom. ; ecas_sara Approved Most recent IF: 4.474  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:156391 Serial 5151  
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Author Altantzis, T.; Lobato, I.; De Backer, A.; Béché, A.; Zhang, Y.; Basak, S.; Porcu, M.; Xu, Q.; Sánchez-Iglesias, A.; Liz-Marzán, L.M.; Van Tendeloo, G.; Van Aert, S.; Bals, S. url  doi
openurl 
  Title Three-Dimensional Quantification of the Facet Evolution of Pt Nanoparticles in a Variable Gaseous Environment Type A1 Journal article
  Year 2019 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 19 Issue 19 Pages 477-481  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Pt nanoparticles play an essential role in a wide variety of catalytic reactions. The activity of the particles strongly depends on their three-dimensional (3D) structure and exposed facets, as well as on the reactive environment. High-resolution electron microscopy has often been used to characterize nanoparticle catalysts but unfortunately most observations so far have been either performed in vacuum and/or using conventional (2D) in situ microscopy. The latter however does not provide direct 3D morphological information. We have implemented a quantitative methodology to measure variations of the 3D atomic structure of nanoparticles under the flow of a selected gas. We were thereby able to quantify refaceting of Pt nanoparticles with atomic resolution during various oxidation−reduction cycles. In a H2 environment, a more faceted surface morphology of the particles was observed with {100} and {111} planes being dominant. On the other hand, in O2 the percentage of {100} and {111} facets decreased and a significant increase of higher order facets was found, resulting in a more rounded morphology. This methodology opens up new opportunities toward in situ characterization of catalytic nanoparticles because for the first time it enables one to directly measure 3D morphology variations at the atomic scale in a specific gaseous reaction environment.  
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  Corporate Author Thesis  
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  Language Wos 000455561300061 Publication Date 2019-01-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.712 Times cited 82 Open Access OpenAccess  
  Notes This work was supported by the European Research Council (Grant 335078 COLOURATOM to S.B. and Grant 770887 PICOMETRICS to S.V.A.). The authors acknowledge funding from the European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M., and Q.X. and MUMMERING 765604 to S.B. and Q.X.). The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15N, G.0369.15N, and G.0267.18N), postdoctoral grants to T.A. and A.D.B, and an FWO [PEGASUS]2 Marie Sklodowska-Curie fellowship to Y.Z. (12U4917N). L.M.L.-M. acknowledges funding from the Spanish Ministerio de Economía y Competitividad (Grant MAT2017-86659-R). We gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan X Pascal GPU used for this research. ecas_sara Realnano 815128; sygma Approved Most recent IF: 12.712  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:156390 Serial 5150  
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Author Barreca, D.; Gri, F.; Gasparotto, A.; Carraro, G.; Bigiani, L.; Altantzis, T.; Žener, B.; Lavrenčič Štangar, U.; Alessi, B.; Padmanaban, D.B.; Mariotti, D.; Maccato, C. url  doi
openurl 
  Title Multi-functional MnO2nanomaterials for photo-activated applications by a plasma-assisted fabrication route Type A1 Journal article
  Year 2019 Publication Nanoscale Abbreviated Journal Nanoscale  
  Volume 11 Issue 1 Pages 98-108  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Supported MnO2-based nanomaterials were fabricated on fluorine-doped tin oxide substrates by plasma enhanced-chemical vapor deposition (PE-CVD) between 100 °C and 400 °C, starting from a fluorinated Mn(II) diamine diketonate precursor. Growth experiments yielded -MnO2 nanosystems with hierarchical morphology tuneable from dendritic structures to quasi-1D nanosystems as a function of growth temperature, whose variation enabled also a concomitant tailoring of the system fluorine content, and of the optical absorption and band gap. Preliminary photocatalytic tests were aimed at the investigation of photoinduced hydrophilic (PH) and solid phase photocatalytic (PC) performances of the present nanomaterials, as well as at the photodegradation of Plasmocorinth B azo-dye aqueous solutions. The obtained findings highlighted an attractive system photoactivity even under visible light, finely tailored by fluorine content, morphological organization and optical properties of the prepared nanostructures. The results indicate that the synthesized MnO2 nanosystems have potential applications as advanced smart materials for anti-fogging/self-cleaning end uses and water purification.  
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  Language Wos 000454327500037 Publication Date 2018-10-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 7.367 Times cited 7 Open Access OpenAccess  
  Notes Padova University DOR 2016–2017, P-DiSC #03BIRD2016-UNIPD projects, HERALD Cost Action MP1402 – 37831 and ACTION post-doc fellowship are acknowledged for financial support. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO). Thanks are also due to Prof. Sara Bals (EMAT, University of Antwerp, Belgium), Prof. Romana Cerc Korošec and to Dr. Lev Matoh (University of Ljubljana, Slovenia), and to Prof. Elza Bontempi (Brescia University, Italy). The work was also supported by EPSRC (award EP/R008841/1, EP/M024938/1). Approved Most recent IF: 7.367  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:156388 Serial 5148  
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Author Gkanatsiou, A.; Lioutas, C.B.; Frangis, N.; Polychroniadis, E.K.; Prystawko, P.; Leszczynski, M.; Altantzis, T.; Van Tendeloo, G. url  doi
openurl 
  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 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  
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  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 (down) EMAT @ emat @UA @ admin @ c:irua:156200 Serial 5149  
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Author van den Bos, K.H.W.; Janssens, L.; De Backer, A.; Nellist, P.D.; Van Aert, S. url  doi
openurl 
  Title The atomic lensing model: new opportunities for atom-by-atom metrology of heterogeneous nanomaterials Type A1 Journal article
  Year 2019 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 203 Issue Pages 155  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The atomic lensing model has been proposed as a promising method facilitating atom-counting in heterogeneous nanocrystals [1]. Here, image simulations will validate the model, which describes dynamical diffraction as a superposition of individual atoms focussing the incident electrons. It will be demonstrated that the model is reliable in the annular dark field regime for crystals having columns containing dozens of atoms. By using the principles of statistical detection theory, it will be shown that this model gives new opportunities for detecting compositional differences.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000465021000020 Publication Date 2018-12-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 4 Open Access OpenAccess  
  Notes The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0369.15N, G.0502.18N and WO.010.16N), and by personal grants to K.H.W. van den Bos and A. De Backer. This project has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (grant agreement No. 770887). Approved Most recent IF: 2.843  
  Call Number (down) EMAT @ emat @UA @ admin @ c:irua:155721 Serial 5074  
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Author Pennycook, T.J.; Martinez, G.T.; O'Leary, C.M.; Yang, H.; Nellist, P.D. pdf  url
doi  openurl
  Title Efficient Phase Contrast Imaging via Electron Ptychography, a Tutorial Type A1 Journal article
  Year 2019 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 25 Issue S2 Pages 2684-2685  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2019-08-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (down) EMAT @ emat @c:irua:172444 Serial 6424  
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Author Chin, C.–M.; Battle, P.D.; Hunter, E.C.; Avdeev, M.; Hendrickx, M.; Hadermann, J. pdf  url
doi  openurl
  Title Magnetic properties of La3Ni2Sb Ta Nb1––O9; from relaxor to spin glass Type A1 Journal article
  Year 2019 Publication Journal of solid state chemistry (Print) Abbreviated Journal Journal of Solid State Chemistry  
  Volume 273 Issue Pages 175-185  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Neutron diffraction experiments conducted at 5 K in a magnetic field 0 < H/kOe < 50 have shown that the monoclinic perovskite La3Ni2TaO9 behaves as a relaxor ferromagnet. Compositions in the series La3Ni2SbxTayNb1–x–yO9 have been synthesized in polycrystalline form. Electron microscopy, X–ray diffraction and neutron diffraction have shown that the solid solutions are largely homogeneous and monophasic. Magnetometry and neutron diffraction have shown that the relaxor magnetisation persists in low fields when x + y = 1 but is rapidly diminished by the introduction of niobium. This change in magnetic behaviour is ascribed to the differences in the d–orbital energies of Sb5+, Nb5+ and Ta5+.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000466261100026 Publication Date 2019-03-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-4596 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes We thank EPSRC for funding through grant EP/M0189541. CMC thanks the Croucher Foundation and the University of Oxford for the award of a graduate scholarship. Approved no  
  Call Number (down) EMAT @ emat @c:irua:166445 Serial 6346  
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Author Prabhakara, V.; Jannis, D.; Béché, A.; Bender, H.; Verbeeck, J. url  doi
openurl 
  Title Strain measurement in semiconductor FinFET devices using a novel moiré demodulation technique Type A1 Journal article
  Year 2019 Publication Semiconductor science and technology Abbreviated Journal Semicond Sci Tech  
  Volume Issue Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Moiré fringes are used throughout a wide variety of applications in physics and

engineering to bring out small variations in an underlying lattice by comparing with another reference lattice. This method was recently demonstrated in Scanning Transmission Electron Microscopy imaging to provide local strain measurement in crystals by comparing the crystal lattice with the scanning raster that then serves as the reference. The images obtained in this way contain a beating fringe pattern with a local period that represents the deviation of the lattice from the reference. In order to obtain the actual strain value, a region containing a full period of the fringe is required, which results in a compromise between strain sensitivity and spatial resolution. In this paper we propose an advanced setup making use of an optimised scanning pattern and a novel phase stepping demodulation scheme. We demonstrate the novel method on a series of 16 nm Si-Ge semiconductor FinFET devices in which strain plays a crucial role in modulating the charge carrier mobility. The obtained results are compared with both Nano-beam diffraction and the recently proposed Bessel beam diffraction technique. The setup provides a much improved spatial resolution over conventional moiré imaging in STEM while at the same time being fast and requiring no specialised diffraction camera as opposed to the diffraction techniques we compare to.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000537721200002 Publication Date 2019-11-29  
  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 8 Open Access  
  Notes The Qu-Ant-EM microscope and the direct electron detector used in the diffraction experiments was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the GOA project “Solarpaint” of the University of Antwerp. We would also like to thank Dr. Thomas Nuytten and Prof. Dr. Wilfried Vandervorst from IMEC, Leuven for their continuous support and collaboration with the project. Approved Most recent IF: 2.305  
  Call Number (down) EMAT @ emat @c:irua:165794 Serial 5445  
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Author Kirkwood, N.; De Backer, A.; Altantzis, T.; Winckelmans, N.; Longo, A.; Antolinez, F.V.; Rabouw, F.T.; De Trizio, L.; Geuchies, J.J.; Mulder, J.T.; Renaud, N.; Bals, S.; Manna, L.; Houtepen, A.J. url  doi
openurl 
  Title Locating and controlling the Zn content in In(Zn)P quantum dots Type A1 Journal article
  Year 2019 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 32 Issue 32 Pages 557-565  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Zinc is routinely employed in the synthesis of InP quantum dots (QDs) to improve the photoluminescence efficiency and carrier mobility of the resulting In(Zn)P alloy nanostructures. The exact location of Zn in the final structures and the mechanism by which it enhances the optoelectronic properties of the QDs is debated. We use synchrotron X-ray absorbance spectroscopy to show that the majority of Zn in In(Zn)P QDs is located at their surface as Zn-carboxylates. However, a small amount of Zn is present inside the bulk of the QDs with the consequent contraction of their lattice, as confirmed by combining high resolution high-angle annular dark-field imaging scanning transmission electron microscopy (HAADF-STEM) with statistical parameter estimation theory. We further demonstrate that the Zn content and its incorporation into the QDs can be tuned by the ligation of commonly employed Zn carboxylate precursors: the use of highly reactive Zn-acetate leads to the formation of undesired Zn3P2 and the final nanostructures being characterized by broad optical features, whereas Zn-carboxylates with longer carbon chains lead to InP crystals with much lower zinc content and narrow optical features. These results can explain the differences between structural and optical properties of In(Zn)P samples reported across the literature, and provide a rational method to tune the amount of Zn in InP nanocrystals and to drive the incorporation of Zn either as surface Zn-carboxylate, as a substitutional dopant inside the InP crystal lattice, or even predominantly as Zn3P2.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000507721600056 Publication Date 2019-12-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 39 Open Access OpenAccess  
  Notes A.J.H. acknowledges support from the European Research Council Horizon 2020 ERC Grant Agreement No. 678004 (Doping on Demand). This research is supported by the Dutch Technology Foundation TTW, which is part of The Netherlands Organization for Scientific Research (NWO), and which is partly funded by Ministry of Economic Affairs. SB acknowledges funding from the European Research Council (grant 815128 REALNANO). The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project funding G.0381.16N and a postdoctoral grant to A.D.B. AJH, LM and JM acknowledge support from the H2020 Collaborative Project TEQ (Grant No. 766900).; sygma Approved Most recent IF: 9.466  
  Call Number (down) EMAT @ emat @c:irua:165234 Serial 5438  
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Author Spaeth, P.; Adhikari, S.; Le, L.; Jollans, T.; Pud, S.; Albrecht, W.; Bauer, T.; Caldarola, M.; Kuipers, L.; Orrit, M. url  doi
openurl 
  Title Circular Dichroism Measurement of Single Metal Nanoparticles Using Photothermal Imaging Type A1 Journal article
  Year 2019 Publication Nano Letters Abbreviated Journal Nano Lett  
  Volume 19 Issue 12 Pages 8934-8940  
  Keywords A1 Journal article; Photothermal microscopy, chirality, circular dichroism, dissymmetry factor, linear dichroism, gold nanostructures; Electron Microscopy for Materials Science (EMAT) ;  
  Abstract Circular dichroism (CD) spectroscopy is a powerful optical technique for the study of chiral materials and molecules. It gives access to an enantioselective signal based on the differential absorption of right and left circularly polarized light, usually obtained through polarization analysis of the light transmitted through a sample of interest. CD is routinely used to determine the secondary structure of proteins and their conformational state. However, CD signals are weak, limiting the use of this powerful technique to ensembles of many molecules. Here, we experimentally realize the concept of photothermal circular dichroism, a technique that combines the enantioselective signal from circular dichroism with the high sensitivity of photothermal microscopy, achieving a superior signal-to-noise ratio to detect chiral nano-objects. As a proof of principle, we studied the chiral response of single plasmonic nanostructures with CD in the visible range, demonstrating a signal-to-noise ratio better than 40 with only 30 ms integration time for these nanostructures. The high signal-to-noise ratio allows us to quantify the CD signal for individual nanoparticles. We show that we can distinguish relative absorption differences for right circularly and left circularly polarized light as small as gmin = 4 × 10–3 for a 30 ms integration time with our current experimental settings. The enhanced sensitivity of our technique extends CD studies to individual nano-objects and opens CD spectroscopy to numbers of molecules much lower than those in conventional experiments.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000502687500074 Publication Date 2019-12-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.712 Times cited Open Access  
  Notes This work was supported by The Netherlands Organisation for Scientific Research (NWO/OCW), as part of the Frontiers of Nanoscience (NanoFront) program, and Open Technology Program (OTP, Project No. 16008). M.C. acknowledges the financial support of the Kavli Institute of Nanoscience Delft through the KIND fellowships program. T.B. and L.K. acknowledge the financial support of the European Research Council (ERC) through Project 340438-CONSTANS. W.A. acknowledges an Individual Fellowship from the Marie Sklodowska-Curie actions (MSCA) under the EU’s Horizon 2020 program (Grant 797153, SOPMEN). The authors acknowledge Dr. Benjamin P. Isaacoff for his help in the initial steps of this project. P.S. thanks Martin Baaske for helpful discussions. M.C. thanks Dr. Felipe Bernal Arango for help with the 3D image rendering. Approved Most recent IF: 12.712  
  Call Number (down) EMAT @ emat @c:irua:165087c:irua:165233 Serial 5439  
Permanent link to this record
 

 
Author Boyat, X.; Ballat-Durand, D.; Marteau, J.; Bouvier, S.; Favergeon, J.; Orekhov, A.; Schryvers, D. pdf  doi
openurl 
  Title Interfacial characteristics and cohesion mechanisms of linear friction welded dissimilar titanium alloys: Ti–5Al–2Sn–2Zr–4Mo–4Cr (Ti17) and Ti–6Al–2Sn–4Zr–2Mo (Ti6242) Type A1 Journal article
  Year 2019 Publication Materials characterization Abbreviated Journal Mater Charact  
  Volume 158 Issue Pages 109942  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract A detailed microstructural examination endeavoring to understand the interfacial phenomena yielding to cohesion

in solid-state assembling processes was performed. This study focuses on the transition zone of a dissimilar

titanium alloy joint obtained by Linear Friction Welding (LFW) the β-metastable Ti17 to the near-α

Ti6242. The transition zone delimitating both alloys is characterized by a sharp microstructure change from

acicular HCP (Hexagonal Close-Packed) α′ martensitic laths in the Ti6242 to equiaxed BCC β (Body-Centered

Cubic) subgrains in the Ti17; these α′ plates were shown to precipitate within prior-β subgrains remarkably more

rotated than the ones formed in the Ti17. Both α′ and β microstructures were found to be intermingled within

transitional subgrains demarcating a limited gradient from one chemical composition to the other. These peculiar

interfacial grains revealed that the cohesive mechanisms between the rubbing surfaces occurred in the

single-phase β domain under severe strain and high-temperature conditions. During the hot deformation process,

the mutual migration of the crystalline interfaces from one material to another assisted by a continuous dynamic

recrystallization process was identified as the main adhesive mechanism at the junction zone. The latter led to

successful cohesion between the rubbing surfaces. Once the reciprocating motion stopped, fast cooling caused

both materials to experience either a βlean→α′ or βlean→βmetastable transformation in the interfacial zone depending

on their local chemical composition. The limited process time and the subsequent hindered chemical

homogenization at the transition zone led to retaining the so-called intermingled α’/βm subgrains constituting

the border between both Ti-alloys.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000503314000018 Publication Date 2019-10-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1044-5803 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.714 Times cited Open Access  
  Notes The authors gratefully acknowledge the financial support of the French National Research Agency (ANR) through the OPTIMUM ANR- 14-CE27-0017 project. The authors would also like to thank the Hautsde- France Region and the European Regional Development Fund (ERDF) 2014/2020 for the co-funding of this work. The authors would also like to thank ACB for providing LFW samples as well as Airbus for their technical support. Approved Most recent IF: 2.714  
  Call Number (down) EMAT @ emat @c:irua:165084 Serial 5441  
Permanent link to this record
 

 
Author Gvozdetskyi, V.; Bhaskar, G.; Batuk, M.; Zhao, X.; Wang, R.; Carnahan, S.L.; Hanrahan, M.P.; Ribeiro, R.A.; Canfield, P.C.; Rossini, A.J.; Wang, C.-Z.; Ho, K.-M.; Hadermann, J.; Zaikina, J.V. url  doi
openurl 
  Title Computationally Driven Discovery of a Family of Layered LiNiB Polymorphs Type A1 Journal article
  Year 2019 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 58 Issue 44 Pages 15855-15862  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Two novel lithium nickel boride polymorphs RT-LiNiB and HT-LiNiB with layered crystal structures are reported. This family of compounds was theoretically predicted by using the adaptive genetic algorithm (AGA) and subsequently synthesized via a hydride route with LiH precursor as a lithium source. Being unique among the known ternary transition metal borides, the LiNiB structures feature Li layers alternating with nearly planar [NiB] layers, composed of Ni hexagonal rings centered by B-B pairs. A comprehensive study using a combination of single crystal/synchrotron powder X-ray diffraction data, solid-state 7Li and 11B NMR, scanning transmission electron microscopy, quantum chemistry calculations, and magnetism has shed light on the intrinsic features of these polymorphic compounds. The unique layered structures of LiNiB compounds make them ultimate precursors to further study their exfoliation, paving a way toward two-dimensional transition metal borides, MBenes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000491219600038 Publication Date 2019-10-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited Open Access  
  Notes the Gordon and Betty Moore Foundation’s EPiQS Initiative through Grant GBMF4411. The Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under contract #DE-AC02-07CH11358. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Approved Most recent IF: 11.994  
  Call Number (down) EMAT @ emat @c:irua:164752 Serial 5433  
Permanent link to this record
 

 
Author Jin, L.; Batuk, M.; Kirschner, F.K.K.; Lang, F.; Blundell, S.J.; Hadermann, J.; Hayward, M.A. url  doi
openurl 
  Title Exsolution of SrO during the Topochemical Conversion of LaSr3CoRuO8to the Oxyhydride LaSr3CoRuO4H4 Type A1 Journal article
  Year 2019 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 58 Issue 21 Pages 14863-14870  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Reaction of the n = 1 Ruddlesden-Popper oxide LaSr3CoRuO8 with CaH2 yields the oxyhydride phase LaSr3CoRuO4H4 via topochemical anion-exchange. Close inspection of X-ray and neutron powder diffraction data in combination with HAADF-STEM images reveals that nanoparticles of SrO are exsolved from the system during the reaction, with the change in cation stoichiometry accommodated by the inclusion of n > 1 (Co/Ru)nOn+1H2n ‘perovskite’ layers into the Ruddlesden-Popper stacking sequence. This novel pseudo-topochemical process offers a new route for the formation of n > 1 Ruddlesden-Popper structured materials. Magnetization data are consistent with a LaSr3Co1+Ru2+O4H4 (Co1+, d8, S = 1; Ru2+, d6, S = 0) oxidation/spin state combination. Neutron diffraction and μ+SR data show no evidence for long-range magnetic order down to 2 K, suggesting the diamagnetic Ru2+ centers impede the Co-Co magnetic exchange interactions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000494894400062 Publication Date 2019-11-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.857 Times cited 1 Open Access  
  Notes We thank P. Manuel for assistance collecting the neutron powder diffraction data. We thank The Leverhulme Trust grant award RPG-2014-366 “Topochemical reduction of 4d and 5d transition metal oxides” for supporting this work. Experiments at the Diamond Light Source were performed as part of the Block Allocation Group award “Oxford Solid State Chemistry BAG to probe composition-structure-property relationships in solids” (EE13284). Investigation by TEM was supported through the FWO grant G035619N. Approved Most recent IF: 4.857  
  Call Number (down) EMAT @ emat @c:irua:164625 Serial 5434  
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Author Skorikov, A.; Albrecht, W.; Bladt, E.; Xie, X.; van der Hoeven, J.E.S.; van Blaaderen, A.; Van Aert, S.; Bals, S. pdf  url
doi  openurl
  Title Quantitative 3D Characterization of Elemental Diffusion Dynamics in Individual Ag@Au Nanoparticles with Different Shapes Type A1 Journal article
  Year 2019 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 13 Issue 13 Pages 13421-13429  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Anisotropic bimetallic nanoparticles are promising candidates for plasmonic and catalytic applications. Their catalytic performance and plasmonic properties are closely linked to the distribution of the two metals, which can change during applications in which the particles are exposed to heat. Due to this fact, correlating the thermal stability of complex heterogeneous nanoparticles to their microstructural properties is of high interest for the practical applications of such materials. Here, we employ quantitative electron tomography in high-angle annular dark-field scanning transmission electron microscopy (HAADFSTEM) mode to measure the 3D elemental diffusion dynamics in individual anisotropic Au−Ag nanoparticles upon heating in situ. This approach allows us to study the elemental redistribution in complex, asymmetric nanoparticles on a single particle level, which has been inaccessible to other techniques so far. In this work, we apply the proposed method to compare the alloying dynamics of Au−Ag nanoparticles with different shapes and compositions and find that the shape of the nanoparticle does not exhibit a significant effect on the alloying speed whereas the composition does. Finally, comparing the experimental results to diffusion simulations allows us to estimate the diffusion coefficients of the metals for individual nanoparticles.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000500650000115 Publication Date 2019-10-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.942 Times cited 29 Open Access OpenAccess  
  Notes This project has received funding from the European Commission (grant 731019, EUSMI) and European Research Council (ERC Consolidator Grants 815128, REALNANO; 770887, PICOMETRICS; 648991, 3MC; and ERC Advanced Grant 291667, HierarSACol). This project has also received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement 823717, ESTEEM3. W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 797153, SOPMEN). E.B. acknowledges a postdoctoral grant 12T2719N from the Research Foundation Flanders (FWO, Belgium). X.X. acknowledges financial support from the EU H2020-MSCAITN-2015 project 676045, MULTIMAT. The authors also acknowledge financial support by the Research Foundation Flanders (FWO grants G038116N, G026718N, and G036915N).; sygma; esteem3JRA; esteem3reported Approved Most recent IF: 13.942  
  Call Number (down) EMAT @ emat @c:irua:164061 Serial 5379  
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Author Nord, M.; Semisalova, A.; Kákay, A.; Hlawacek, G.; MacLaren, I.; Liersch, V.; Volkov, O.M.; Makarov, D.; Paterson, G.W.; Potzger, K.; Lindner, J.; Fassbender, J.; McGrouther, D.; Bali, R. pdf  url
doi  openurl
  Title Strain Anisotropy and Magnetic Domains in Embedded Nanomagnets Type A1 Journal article
  Year 2019 Publication Small Abbreviated Journal Small  
  Volume Issue Pages 1904738  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Nanoscale modifications of strain and magnetic anisotropy can open pathways to engineering magnetic domains for device applications. A periodic magnetic domain structure can be stabilized in sub‐200 nm wide linear as well as curved magnets, embedded within a flat non‐ferromagnetic thin film. The nanomagnets are produced within a non‐ferromagnetic B2‐ordered Fe60Al40 thin film, where local irradiation by a focused ion beam causes the formation of disordered and strongly ferromagnetic regions of A2 Fe60Al40. An anisotropic lattice relaxation is observed, such that the in‐plane lattice parameter is larger when measured parallel to the magnet short‐axis as compared to its length. This in‐plane structural anisotropy manifests a magnetic anisotropy contribution, generating an easy‐axis parallel to the short axis. The competing effect of the strain and shape anisotropies stabilizes a periodic domain pattern in linear as well as spiral nanomagnets, providing a versatile and geometrically controllable path to engineering the strain and thereby the magnetic anisotropy at the nanoscale.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000495563400001 Publication Date 2019-11-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1613-6810 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.643 Times cited 2 Open Access  
  Notes Deutsche Forschungsgemeinschaft, BA5656/1‐1 ; Engineering and Physical Sciences Research Council, EP/M009963/1 ; Approved Most recent IF: 8.643  
  Call Number (down) EMAT @ emat @c:irua:164059 Serial 5376  
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Author Nord, M.; Verbeeck, J. pdf  doi
openurl 
  Title Towards Reproducible and Transparent Science of (Big) Electron Microscopy Data Using Version Control Type P1 Proceeding
  Year 2019 Publication Microscopy and microanalysis T2 – Microscopy & Microanalysis 2019, 4-8 August, 2019, Portland, Oregon Abbreviated Journal Microsc Microanal  
  Volume 25 Issue S2 Pages 232-233  
  Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2019-08-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276 ISBN Additional Links UA library record  
  Impact Factor 1.891 Times cited Open Access  
  Notes Approved Most recent IF: 1.891  
  Call Number (down) EMAT @ emat @c:irua:164058 Serial 5377  
Permanent link to this record
 

 
Author Ramachandran, R.K.; Filez, M.; Solano, E.; Poelman, H.; Minjauw, M.M.; Van Daele, M.; Feng, J.-Y.; La Porta, A.; Altantzis, T.; Fonda, E.; Coati, A.; Garreau, Y.; Bals, S.; Marin, G.B.; Detavernier, C.; Dendooven, J. url  doi
openurl 
  Title Chemical and Structural Configuration of Pt Doped Metal Oxide Thin Films Prepared by Atomic Layer Deposition Type A1 Journal article
  Year 2019 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 31 Issue 31 Pages 9673-9683  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)  
  Abstract Pt doped semiconducting metal oxides and Pt metal clusters embedded in an oxide matrix are of interest for applications such as catalysis and gas sensing, energy storage and memory devices. Accurate tuning of the dopant level is crucial for adjusting the properties of these materials. Here, a novel atomic layer deposition (ALD) based method for doping Pt into In2O3 in specific, and metals in metal oxides in general, is demonstrated. This approach combines alternating exposures of Pt and In2O3 ALD processes in a single ‘supercycle’, followed by supercycle repetition leading to multilayered nanocomposites. The atomic level control of ALD and its conformal nature make the method suitable for accurate dopant control even on high surface area supports. Oxidation state, local structural environment and crystalline phase of the embedded Pt dopants were obtained by means of X-ray characterization methods and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). In addition, this approach allows characterization of the nucleation stages of metal ALD processes, by stacking those states multiple times in an oxide matrix. Regardless of experimental conditions, a few Pt ALD cycles leads to the formation of oxidized Pt species due to their highly dispersed nature, as proven by X-ray absorption spectroscopy (XAS). Grazing-incidence small-angle X-ray scattering (GISAXS) and highresolution scanning transmission electron microscopy, combined with energy dispersive X-ray spectroscopy (HR-STEM/EDXS) show that Pt is evenly distributed in the In2O3 metal oxide matrix without the formation of clusters. For a larger number of Pt ALD

cycles, typ. > 10, the oxidation state gradually evolves towards fully metallic, and metallic Pt clusters are obtained within the In2O3 metal oxide matrix. This work reveals how tuning of the ALD supercycle approach for Pt doping allows controlled engineering of the Pt compositional and structural configuration within a metal oxide matrix.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000502418000010 Publication Date 2019-11-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 6 Open Access OpenAccess  
  Notes This research was supported by the Flemish Research Foundation (FWO-Vlaanderen), the Flemish Government (Long term structural funding – Methusalem funding and Medium scale research infrastructure funding-Hercules funding), the Special Research Fund BOF of Ghent University (GOA 01G01513) and the CALIPSO Trans National Access Program funded by the European Commission in supplying financing of travel costs. We are grateful to the SIXS and SAMBA-SOLEIL staff for smoothly running the beamline facilities. J.D. and R.K.R. are postdoctoral fellows of the FWO. Approved Most recent IF: 9.466  
  Call Number (down) EMAT @ emat @c:irua:164056 Serial 5380  
Permanent link to this record
 

 
Author Idrissi, H.; Ghidelli, M.; Béché, A.; Turner, S.; Gravier, S.; Blandin, J.-J.; Raskin, J.-P.; Schryvers, D.; Pardoen, T. url  doi
openurl 
  Title Atomic-scale viscoplasticity mechanisms revealed in high ductility metallic glass films Type A1 Journal article
  Year 2019 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 9 Issue 1 Pages 13426  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The fundamental plasticity mechanisms in thin freestanding Zr65Ni35 metallic glass films are investigated in order to unravel the origin of an outstanding strength/ductility balance. The deformation process is homogenous until fracture with no evidence of catastrophic shear banding. The creep/relaxation behaviour of the films was characterized by on-chip tensile testing, revealing an activation volume in the range 100–200 Å3. Advanced high-resolution transmission electron microscopy imaging and spectroscopy exhibit a very fine glassy nanostructure with well-defined dense Ni-rich clusters embedded in Zr-rich clusters of lower atomic density and a ~2–3 nm characteristic length scale. Nanobeam electron diffraction analysis reveals that the accumulation of plastic deformation at roomtemperature

correlates with monotonously increasing disruption of the local atomic order. These results provide experimental evidences of the dynamics of shear transformation zones activation in metallic glasses. The impact of the nanoscale structural heterogeneities on the mechanical properties including the rate dependent behaviour is discussed, shedding new light on the governing plasticity mechanisms in metallic glasses with initially heterogeneous atomic arrangement.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000486139700008 Publication Date 2019-09-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited Open Access  
  Notes H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the FNRS under Grant PDR – T.0178.19. FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’) and Hercules fund ‘Direct electron detector for soft matter TEM’ from Flemish Government are acknowledged. Approved Most recent IF: 4.259  
  Call Number (down) EMAT @ emat @c:irua:162786 Serial 5375  
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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. pdf  url
doi  openurl
  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 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 (down) EMAT @ emat @c:irua:162640 Serial 5361  
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Author Nerl, H.C.; Pokle, A.; Jones, L.; Müller‐Caspary, K.; Bos, K.H.W.; Downing, C.; McCarthy, E.K.; Gauquelin, N.; Ramasse, Q.M.; Lobato, I.; Daly, D.; Idrobo, J.C.; Van Aert, S.; Van Tendeloo, G.; Sanvito, S.; Coleman, J.N.; Cucinotta, C.S.; Nicolosi, V. pdf  url
doi  openurl
  Title Self‐Assembly of Atomically Thin Chiral Copper Heterostructures Templated by Black Phosphorus Type A1 Journal article
  Year 2019 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater  
  Volume 29 Issue 37 Pages 1903120  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000478478400001 Publication Date 2019-07-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1616-301X ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 1 Open Access OpenAccess  
  Notes European Research Council, 2DNanoCaps TC2D CoG 3D2DPrint CoG Picometrics grant agreement No. 770887; Engineering and Physical Sciences Research Council, EP/P033555/1 EP/R029431 ; Science Foundation Ireland, HPC1600932 ; Approved Most recent IF: 12.124  
  Call Number (down) EMAT @ emat @c:irua:161901 Serial 5362  
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Author Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J. pdf  url
doi  openurl
  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 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 (down) EMAT @ emat @c:irua:161847 Serial 5295  
Permanent link to this record
 

 
Author Choudhary, K.; Bercx, M.; Jiang, J.; Pachter, R.; Lamoen, D.; Tavazza, F. pdf  url
doi  openurl
  Title Accelerated Discovery of Efficient Solar Cell Materials Using Quantum and Machine-Learning Methods Type A1 Journal article
  Year 2019 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 31 Issue 15 Pages 5900-5908  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  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.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000480826900060 Publication Date 2019-08-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 6 Open Access  
  Notes ; ; Approved Most recent IF: 9.466  
  Call Number (down) EMAT @ emat @c:irua:161814 Serial 5291  
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