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Author Fatermans, J.; Romolini, G.; Altantzis, T.; Hofkens, J.; Roeffaers, M.B.J.; Bals, S.; Van Aert, S.
Title Atomic-scale detection of individual lead clusters confined in Linde Type A zeolites Type A1 Journal article
Year 2022 Publication Nanoscale Abbreviated Journal Nanoscale
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Structural analysis of metal clusters confined in nanoporous materials is typically performed by X-ray-driven techniques. Although X-ray analysis has proved its strength in the characterization of metal clusters, it provides averaged structural information. Therefore, we here present an alternative workflow for bringing the characterization of confined metal clusters towards the local scale. This workflow is based on the combination of aberration-corrected transmission electron microscopy (TEM), TEM image simulations, and powder X-ray diffraction (XRD) with advanced statistical techniques. In this manner, we were able to characterize the clustering of Pb atoms in Linde Type A (LTA) zeolites with Pb loadings as low as 5 wt%. Moreover, individual Pb clusters could be directly detected. The proposed methodology thus enables a local-scale characterization of confined metal clusters in zeolites. This is important for further elucidation of the connection between the structure and the physicochemical properties of such systems.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000809619900001 Publication Date 0000-00-00
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 6.7 Times cited 2 Open Access OpenAccess
Notes The authors acknowledge the Research Foundation Flanders through project fundings (FWO, G026718N, G050218N, ZW15_09-G0H6316N, and W002221N) and through a PhD scholarship to G.R. (grant 11C6920N), as well as iBOF-21-085 PERSIST. T.A. and S.V.A. acknowledge funding from the University of Antwerp Research fund (BOF). J.H. acknowledges the Flemish government through long-term structural funding Methusalem (CASAS2, Meth/15/04) and the MPI as MPI fellow. M.R. acknowledges funding by the KU Leuven Research Fund (C14/19/079). S.B. and S.V.A. acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ERC Consolidator Grants No. 815128−REALNANO and No. 770887−PICOMETRICS). The authors thank Dr. D. Chernyshov for the collection of XRD measurements. Approved Most recent IF: 6.7
Call Number (down) EMAT @ emat @c:irua:189061 Serial 7076
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Author Altantzis, T.; Wang, D.; Kadu, A.; van Blaaderen, A.; Bals, S.
Title Optimized 3D Reconstruction of Large, Compact Assemblies of Metallic Nanoparticles Type A1 Journal article
Year 2021 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume 125 Issue 47 Pages 26240-26246
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract 3D characterization of assemblies of nanoparticles is of great importance to determine their structure-property connection. Such investigations become increasingly more challenging when the assemblies become larger and more compact. In this paper, we propose an optimized approach for electron tomography to minimize artefacts related to beam broadening in High Angle Annular Dark-Field Scanning Transmission Electron Microscopy mode. These artefacts are typically present at one side of the reconstructed 3D data set for thick nanoparticle assemblies. To overcome this problem, we propose a procedure in which two tomographic tilt series of the same sample are acquired. After acquiring the first series, the sample is flipped over 180o, and a second tilt series is acquired. By merging the two reconstructions, blurring in the reconstructed volume is minimized. Next, this approach is combined with an advanced three-dimensional reconstruction algorithm yielding quantitative structural information. Here, the approach is applied to a thick and compact assembly of spherical Au nanoparticles, but the methodology can we used to investigate a broad range of samples.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000752810100031 Publication Date 2021-12-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 4 Open Access OpenAccess
Notes This work was supported by the European Research Council (grant No. 815128−REALNANO to S.B.). T.A. acknowledges the University of Antwerp Research fund (BOF). D.W. and A.v.B. acknowledge partial financial support from the European Research Council under the European Union’s Seventh Framework Program (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. D.W. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 894254 SuprAtom).; sygmaSB Approved Most recent IF: 4.536
Call Number (down) EMAT @ emat @c:irua:185224 Serial 6904
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Author Zheng, Y.-R.; Vernieres, J.; Wang, Z.; Zhang, K.; Hochfilzer, D.; Krempl, K.; Liao, T.-W.; Presel, F.; Altantzis, T.; Fatermans, J.; Scott, S.B.; Secher, N.M.; Moon, C.; Liu, P.; Bals, S.; Van Aert, S.; Cao, A.; Anand, M.; Nørskov, J.K.; Kibsgaard, J.; Chorkendorff, I.
Title Monitoring oxygen production on mass-selected iridium–tantalum oxide electrocatalysts Type A1 Journal article
Year 2021 Publication Nature Energy Abbreviated Journal Nat Energy
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Development of low-cost and high-performance oxygen evolution reaction catalysts is key to implementing polymer electrolyte membrane water electrolyzers for hydrogen production. Iridium-based oxides are the state-of-the-art acidic oxygen evolution reactio catalysts but still suffer from inadequate activity and stability, and iridium's scarcity motivates the discovery of catalysts with lower iridium loadings. Here we report a mass-selected iridium-tantalum oxide catalyst prepared by a magnetron-based cluster source with considerably reduced noble-metal loadings beyond a commercial IrO2 catalyst. A sensitive electrochemistry/mass-spectrometry instrument coupled with isotope labelling was employed to investigate the oxygen production rate under dynamic operating conditions to account for the occurrence of side reactions and quantify the number of surface active sites. Iridium-tantalum oxide nanoparticles smaller than 2 nm exhibit a mass activity of 1.2 ± 0.5 kA “g” _“Ir” ^“-1” and a turnover frequency of 2.3 ± 0.9 s-1 at 320 mV overpotential, which are two and four times higher than those of mass-selected IrO2, respectively. Density functional theory calculations reveal that special iridium coordinations and the lowered aqueous decomposition free energy might be responsible for the enhanced performance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000728458000001 Publication Date 2021-12-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2058-7546 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 95 Open Access OpenAccess
Notes Y.-R.Z. and Z.W acknowledge funding from the Toyota Research Institute. This project has received funding from VILLUM FONDEN (grant no. 9455) and the European Research Council under the European Union’s Horizon 2020 research and innovation programme (grants no. 741860-CLUNATRA, no. 815128−REALNANO and no. 770887−PICOMETRICS). S.B. and S.V.A. acknowledge funding from the Research Foundation Flanders (FWO, G026718N and G050218N). T.A. acknowledges the University of Antwerp Research Fund (BOF). STEM measurements were supported by the European Union's Horizon 2020 Research Infrastructure-Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3.; sygmaSB Approved Most recent IF: NA
Call Number (down) EMAT @ emat @c:irua:184794 Serial 6903
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Author Hudry, D.; De Backer, A.; Popescu, R.; Busko, D.; Howard, I.A.; Bals, S.; Zhang, Y.; Pedrazo‐Tardajos, A.; Van Aert, S.; Gerthsen, D.; Altantzis, T.; Richards, B.S.
Title Interface Pattern Engineering in Core‐Shell Upconverting Nanocrystals: Shedding Light on Critical Parameters and Consequences for the Photoluminescence Properties Type A1 Journal article
Year 2021 Publication Small Abbreviated Journal Small
Volume Issue Pages 2104441
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Advances in controlling energy migration pathways in core-shell lanthanide (Ln)-based hetero-nanocrystals (HNCs) have relied heavily on assumptions about how optically active centers are distributed within individual HNCs. In this article, it is demonstrated that different types of interface patterns can be formed depending on shell growth conditions. Such interface patterns are not only identified but also characterized with spatial resolution ranging from the nanometer- to the atomic-scale. In the most favorable cases, atomic-scale resolved maps of individual particles are obtained. It is also demonstrated that, for the same type of core-shell architecture, the interface pattern can be engineered with thicknesses of just 1 nm up to several tens of nanometers. Total alloying between the core and shell domains is also possible when using ultra-small particles as seeds. Finally, with different types of interface patterns (same architecture and chemical composition of the core and shell domains) it is possible to modify the output color (yellow, red, and green-yellow) or change (improvement or degradation) the absolute upconversion quantum yield. The results presented in this article introduce an important paradigm shift and pave the way toward the emergence of a new generation of core-shell Ln-based HNCs with better control over their atomic-scale organization.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000710758000001 Publication Date 2021-10-25
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 17 Open Access OpenAccess
Notes The authors would like to acknowledge the financial support provided by the Helmholtz Recruitment Initiative Fellowship (B.S.R.) and the Helmholtz Association's Research Field Energy (Materials and Technologies for the Energy Transition program, Topic 1 Photovoltaics and Wind Energy). The authors would like to thank the Karlsruhe Nano Micro Facility (KNMF) for STEM access. 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 PICOMETRICS to S.V.A. and Grant agreement no. 815128 REALNANO to S.B.). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through Projects no. G.0502.18N, G.0267.18N, and a postdoctoral grant to A.D.B. T.A. acknowledges funding from the University of Antwerp Research fund (BOF). This project had received funding (EUSMI proposal #E181100205) from the European Union's Horizon 2020 Research and Innovation Programme under Grant agreement no 731019 (EUSMI). D.H. would like to thank “CGFigures” for helpful tutorials on 3D graphics with Blender.; sygmaSB Approved Most recent IF: 8.643
Call Number (down) EMAT @ emat @c:irua:183285 Serial 6817
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Author Albrecht, W.; Arslan Irmak, E.; Altantzis, T.; Pedrazo‐Tardajos, A.; Skorikov, A.; Deng, T.‐S.; van der Hoeven, J.E.S.; van Blaaderen, A.; Van Aert, S.; Bals, S.
Title 3D Atomic‐Scale Dynamics of Laser‐Light‐Induced Restructuring of Nanoparticles Unraveled by Electron Tomography Type A1 Journal article
Year 2021 Publication Advanced Materials Abbreviated Journal Adv Mater
Volume Issue Pages 2100972
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Understanding light–matter interactions in nanomaterials is crucial for

optoelectronic, photonic, and plasmonic applications. Specifically, metal

nanoparticles (NPs) strongly interact with light and can undergo shape

transformations, fragmentation and ablation upon (pulsed) laser excitation.

Despite being vital for technological applications, experimental insight into

the underlying atomistic processes is still lacking due to the complexity of

such measurements. Herein, atomic resolution electron tomography is performed

on the same mesoporous-silica-coated gold nanorod, before and after

femtosecond laser irradiation, to assess the missing information. Combined

with molecular dynamics (MD) simulations based on the experimentally

determined 3D atomic-scale morphology, the complex atomistic rearrangements,

causing shape deformations and defect generation, are unraveled.

These rearrangements are simultaneously driven by surface diffusion, facet

restructuring, and strain formation, and are influenced by subtleties in the

atomic distribution at the surface.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000671662000001 Publication Date 2021-07-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 8 Open Access OpenAccess
Notes W.A. and E.A.I. contributed equally to this work. The authors acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ERC Consolidator Grants No. 815128 – REALNANO and No. 770887 – PICOMETRICS), the European Union’s Seventh Framework Programme (ERC Advanced Grant No. 291667 – HierarSACol), and the European Commission (EUSMI). W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in the Horizon2020 program (Grant 797153, SOPMEN). T.-S.D. acknowledges financial support from the National Science Foundation of China (NSFC, Grant No. 61905056). The authors also acknowledge financial support by the Research Foundation Flanders (FWO Grant G.0267.18N).; sygmaSB Approved Most recent IF: 19.791
Call Number (down) EMAT @ emat @c:irua:179781 Serial 6805
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Author Bagiński, M.; Pedrazo-Tardajos, A.; Altantzis, T.; Tupikowska, M.; Vetter, A.; Tomczyk, E.; Suryadharma, R.N.S.; Pawlak, M.; Andruszkiewicz, A.; Górecka, E.; Pociecha, D.; Rockstuhl, C.; Bals, S.; Lewandowski, W.
Title Understanding and Controlling the Crystallization Process in Reconfigurable Plasmonic Superlattices Type A1 Journal article
Year 2021 Publication Acs Nano Abbreviated Journal Acs Nano
Volume Issue Pages acsnano.0c09746
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract The crystallization of nanomaterials is a primary source of solid-state, photonic structures. Thus, a detailed understanding of this process is of paramount importance for the successful application of photonic nanomaterials in emerging optoelectronic technologies. While colloidal crystallization has been thoroughly studied, for example, with advanced in situ electron microscopy methods, the noncolloidal crystallization (freezing) of nanoparticles (NPs) remains so far unexplored. To fill this gap, in this work, we present proof-of principle experiments decoding a crystallization of reconfigurable assemblies of NPs at a solid state. The chosen material corresponds to an excellent testing bed, as it enables both in situ and ex situ investigation using X-ray diffraction (XRD), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), atomic force microscopy (AFM), and optical spectroscopy in visible and ultraviolet range (UV−vis) techniques. In particular, ensemble measurements with small-angle XRD highlighted the dependence of the correlation length in the NPs assemblies on the number of heating/cooling cycles and the rate of cooling. Ex situ TEM imaging further supported these results by revealing a dependence of domain size and structure on the sample preparation route and by showing we can control the domain size over 2 orders of magnitude. The application of HAADF-STEM tomography, combined with in situ thermal control, provided three-dimensional single-particle level information on the positional order evolution within assemblies. This combination of real and reciprocal space provides insightful information on the anisotropic, reversibly reconfigurable assemblies of NPs. TEM measurements also highlighted the importance of interfaces in the polydomain structure of nanoparticle solids, allowing us to understand experimentally observed differences in UV−vis extinction spectra of the differently prepared crystallites. Overall, the obtained results show that the combination of in situ heating HAADF-STEM tomography with XRD and ex situ TEM techniques is a powerful approach to study nanoparticle freezing processes and to reveal the crucial impact of disorder in the solid-state aggregates of NPs on their plasmonic properties.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000634569100101 Publication Date 2021-02-23
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 10 Open Access OpenAccess
Notes Ministerstwo Nauki i Szkolnictwa Wyzszego, 0112/DIA/2019/48 ; European Commission, 731019 E171000009 (EUSMI) ; Narodowe Centrum Nauki, 2016/21/N/ST5/03356 ; Deutsche Forschungsgemeinschaft, RO 3640/12-1 ; Fundacja na rzecz Nauki Polskiej, First TEAM2016–2/15 ; European Research Council, 815128 (REALNANO) ; sygma; Approved Most recent IF: 13.942
Call Number (down) EMAT @ emat @c:irua:175872 Serial 6673
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Author Milagres de Oliveira, T.; Albrecht, W.; González-Rubio, G.; Altantzis, T.; Lobato Hoyos, I.P.; Béché, A.; Van Aert, S.; Guerrero-Martínez, A.; Liz-Marzán, L.M.; Bals, S.
Title 3D Characterization and Plasmon Mapping of Gold Nanorods Welded by Femtosecond Laser Irradiation Type A1 Journal article
Year 2020 Publication Acs Nano Abbreviated Journal Acs Nano
Volume 14 Issue Pages acsnano.0c02610
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Ultrafast laser irradiation can induce morphological and structural changes in plasmonic nanoparticles. Gold nanorods (Au NRs), in particular, can be welded together upon irradiation with femtosecond laser pulses, leading to dimers and trimers through the formation of necks between individual nanorods. We used electron tomography to determine the 3D (atomic) structure at such necks for representative welding geometries and to characterize the induced defects. The spatial distribution of localized surface plasmon modes for different welding configurations was assessed by electron energy loss spectroscopy. Additionally, we were able to directly compare the plasmon line width of single-crystalline and welded Au NRs with single defects at the same resonance energy, thus making a direct link between the structural and plasmonic properties. In this manner, we show that the occurrence of (single) defects results in significant plasmon broadening.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000586793400016 Publication Date 2020-08-19
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 17.1 Times cited 25 Open Access OpenAccess
Notes This project has received funding from the European Research Council under the European Union's Horizon 2020 research and innovation program (ERC Consolidator Grants #815128 – REALNANO and #770887 – PICOMETRICS). The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project funding G.0381.16N and G.0267.18N. W.A. acknowledges an Individual Fellowship funded by the Marie 27 Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 797153, SOPMEN). G.G.-R. acknowledge receipt of FPI Fellowship from the Spanish MINECO. This work has been funded by the Spanish Ministry of Science, Innovation and Universities (MICIU) (Grants RTI2018-095844-B-I00 and MAT2017-86659-R) and the Madrid Regional Government (Grant P2018/NMT-4389). A.B. acknowledges funding from FWO project G093417N and from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. L.M.L.-M. acknowledges the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720); Comunidad de Madrid, P2018/NMT-4389 ; Ministerio de Ciencia, Innovación y Universidades, MAT2017-86659-R RTI2018-095844-B-I00 ; Ministerio de Economía y Competitividad; H2020 Marie Sklodowska-Curie Actions, 797153 ; Fonds Wetenschappelijk Onderzoek, G.0267.18N G.0381.16N G093417N ; H2020 Research Infrastructures, 823717 ; H2020 European Research Council, 770887 815128 ; Agencia Estatal de Investigación, Ministerio de Ciencia, Innovación y Universidades, MDM-2017-0720 ; sygma Approved Most recent IF: 17.1; 2020 IF: 13.942
Call Number (down) EMAT @ emat @c:irua:172440 Serial 6426
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Author Agrawal, H.; Patra, B.K.; Altantzis, T.; De Backer, A.; Garnett, E.C.
Title Quantifying Strain and Dislocation Density at Nanocube Interfaces after Assembly and Epitaxy Type A1 Journal article
Year 2020 Publication Acs Applied Materials & Interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 12 Issue 7 Pages 8788-8794
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Nanoparticle self-assembly and epitaxy are utilized extensively to make 1D and 2D structures with complex shapes. High-resolution transmission electron microscopy (HRTEM) has shown that single-crystalline interfaces can form, but little is known about the strain and dislocations at these interfaces. Such information is critically important for applications: drastically reducing

dislocation density was the key breakthrough enabling widespread implementation of light-emitting diodes, while strain engineering has been fundamental to modern high-performance transistors, solar cells, and thermoelectrics. In this work, the interfacial defect and strain formation after selfassembly and room temperature epitaxy of 7 nm Pd nanocubes capped with polyvinylpyrrolidone (PVP) is examined. It is observed that, during ligand removal, the cubes move over large distances on the substrate, leading to both spontaneous self-assembly and epitaxy to form single crystals. Subsequently, atomically resolved images are used to quantify the strain and dislocation density at the epitaxial interfaces between cubes with different lateral and angular misorientations. It is shown that dislocation- and strain-free interfaces form when the nanocubes align parallel to each other. Angular misalignment between adjacent cubes does not necessarily lead to grain boundaries but does cause dislocations, with higher densities associated with larger rotations.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000515214300101 Publication Date 2020-02-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.5 Times cited Open Access OpenAccess
Notes Fonds Wetenschappelijk Onderzoek; H2020 Research Infrastructures, 731019 ; Nederlandse Organisatie voor Wetenschappelijk Onderzoek, 14846 ; The work at AMOLF is part of the research program of the “Nederlandse Organisatie voor Wetenschappelijk Onderzoek” (NWO). This work was supported by the NWO VIDI grant (project no. 14846). The authors would like to thank Reinout Jaarsma and Dr. Sven Askes for helping with the XPS measurements. A.D.B. acknowledges a postdoctoral grant from the research foundation Flanders (FWO). The authors acknowledge financial support from the European Commission under the Horizon 2020 Programme by means of the grant agreement no. 731019 EUSMI. Approved Most recent IF: 9.5; 2020 IF: 7.504
Call Number (down) EMAT @ emat @c:irua:167770 Serial 6398
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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.
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 Ramachandran, R.K.; Filez, M.; Solano, E.; Poelman, H.; Minjauw, M.M.; Van Daele, M.; Feng, J.-Y.; La Porta, A.; Altantzis, T.; Fonda, E.; Coati, A.; Garreau, Y.; Bals, S.; Marin, G.B.; Detavernier, C.; Dendooven, J.
Title Chemical and Structural Configuration of Pt Doped Metal Oxide Thin Films Prepared by Atomic Layer Deposition Type A1 Journal article
Year 2019 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 31 Issue 31 Pages 9673-9683
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Pt doped semiconducting metal oxides and Pt metal clusters embedded in an oxide matrix are of interest for applications such as catalysis and gas sensing, energy storage and memory devices. Accurate tuning of the dopant level is crucial for adjusting the properties of these materials. Here, a novel atomic layer deposition (ALD) based method for doping Pt into In2O3 in specific, and metals in metal oxides in general, is demonstrated. This approach combines alternating exposures of Pt and In2O3 ALD processes in a single ‘supercycle’, followed by supercycle repetition leading to multilayered nanocomposites. The atomic level control of ALD and its conformal nature make the method suitable for accurate dopant control even on high surface area supports. Oxidation state, local structural environment and crystalline phase of the embedded Pt dopants were obtained by means of X-ray characterization methods and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). In addition, this approach allows characterization of the nucleation stages of metal ALD processes, by stacking those states multiple times in an oxide matrix. Regardless of experimental conditions, a few Pt ALD cycles leads to the formation of oxidized Pt species due to their highly dispersed nature, as proven by X-ray absorption spectroscopy (XAS). Grazing-incidence small-angle X-ray scattering (GISAXS) and highresolution scanning transmission electron microscopy, combined with energy dispersive X-ray spectroscopy (HR-STEM/EDXS) show that Pt is evenly distributed in the In2O3 metal oxide matrix without the formation of clusters. For a larger number of Pt ALD

cycles, typ. > 10, the oxidation state gradually evolves towards fully metallic, and metallic Pt clusters are obtained within the In2O3 metal oxide matrix. This work reveals how tuning of the ALD supercycle approach for Pt doping allows controlled engineering of the Pt compositional and structural configuration within a metal oxide matrix.
Address
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
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Author Barreca, D.; Gri, F.; Gasparotto, A.; Altantzis, T.; Gombac, V.; Fornasiero, P.; Maccato, C.
Title Insights into the Plasma-Assisted Fabrication and Nanoscopic Investigation of Tailored MnO2Nanomaterials Type A1 Journal Article
Year 2018 Publication Inorganic Chemistry Abbreviated Journal Inorg Chem
Volume 57 Issue 23 Pages 14564-14573
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract Among transition metal oxides, MnO2 is of considerable importance for various technological end-uses,from heterogeneous catalysis to gas sensing, owing to its

structural flexibility and unique properties at the nanoscale. In this work, we demonstrate the successful fabrication of supported MnO2 nanomaterials by a catalyst-free, plasmaassisted process starting from a fluorinated manganese(II)

molecular source in Ar/O2 plasmas. A thorough multitechnique characterization aimed at the systematic investigation of material structure, chemical composition, and

morphology revealed the formation of F-doped, oxygendeficient, MnO2-based nanomaterials, with a fluorine content tunable as a function of growth temperature (TG). Whereas phase-pure β-MnO2 was obtained for 100 °C ≤ TG ≤ 300 °C, the formation of mixed phase MnO2 + Mn2O3 nanosystems took place at 400 °C. In addition, the system nano-organization could be finely tailored, resulting in a controllable evolution from wheat-ear columnar arrays to high aspect ratio pointed-tip nanorod assemblies. Concomitantly, magnetic force microscopy analyses suggested the formation of spin domains with features dependent on material morphology. Preliminary tests in Vislight activated photocatalytic degradation of rhodamine B aqueous solutions pave the way to possible applications of the target materials in wastewater purification.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000452344400016 Publication Date 2018-12-03
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 Open Access Not_Open_Access
Notes The present work was financially supported by Padova University DOR 2016−2018 and P-DiSC #03BIRD2016- UNIPD projects. T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO). Thanks are also due to Prof. Sara Bals (EMAT, University of Antwerp, Belgium) and to Dr. Giorgio Carraro (Department of Chemical Sciences, Padova University, Italy) for valuable support and experimental assistance. Approved Most recent IF: 4.857
Call Number (down) EMAT @ emat @c:irua:156245 Serial 5147
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Author Serrano-Sevillano, J.; Reynaud, M.; Saracibar, A.; Altantzis, T.; Bals, S.; van Tendeloo, G.; Casas-Cabanas, M.
Title Enhanced electrochemical performance of Li-rich cathode materials through microstructural control Type A1 Journal article
Year 2018 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 20 Issue 20 Pages 23112-23122
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The microstructural complexity of Li-rich cathode materials has so far hampered understanding the critical link between size, morphology and structural defects with both capacity and voltage fadings that this family of materials exhibits. Li2MnO3 is used here as a model material to extract reliable structure–property

relationships that can be further exploited for the development of high-performing and long-lasting Li-rich oxides. A series of samples with microstructural variability have been prepared and thoroughly characterized using the FAULTS software, which allows quantification of planar defects and extraction of

average crystallite sizes. Together with transmission electron microscopy (TEM) and density functional theory (DFT) results, the successful application of FAULTS analysis to Li2MnO3 has allowed rationalizing the synthesis conditions and identifying the individual impact of concurrent microstructural features on

both voltage and capacity fadings, a necessary step for the development of high-capacity Li-ion cathode materials with enhanced cycle life.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000445220500071 Publication Date 2018-08-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 36 Open Access OpenAccess
Notes This work was supported by the Spanish Ministerio de la Economı´a y de la Competitividad through the project IONSTORE (MINECO ref. ENE2016-81020-R). The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). JSS and AS are grateful for computing time provided by the Spanish i2Basque Centers. MR acknowledges the Spanish State for its financial support through her post-doctoral grant Juan de la Cierva – Formacio´n (MINECO ref. FJCI-2014-19990) and her international mobility grant Jose´ Castillejos (MECD ref. CAS15/00354). S. B. acknowledges funding from the European Research Council (ERC starting grant #335078 Colouratom) and T. A. a postdoctoral grant from the Research Foundation Flanders (FWO). (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ecas_sara Approved Most recent IF: 4.123
Call Number (down) EMAT @ emat @c:irua:154782UA @ admin @ c:irua:154782 Serial 5062
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Author Guzzinati, G.; Altantzis, T.; Batuk, M.; De Backer, A.; Lumbeeck, G.; Samaee, V.; Batuk, D.; Idrissi, H.; Hadermann, J.; Van Aert, S.; Schryvers, D.; Verbeeck, J.; Bals, S.
Title Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp Type A1 Journal article
Year 2018 Publication Materials Abbreviated Journal Materials
Volume 11 Issue 11 Pages 1304
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000444112800041 Publication Date 2018-07-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1996-1944 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.654 Times cited 15 Open Access OpenAccess
Notes Fonds Wetenschappelijk Onderzoek, G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N AUHA13009 ; European Research Council, COLOURATOM 335078 ; Universiteit Antwerpen, GOA Solarpaint ; G. Guzzinati, T. Altantzis and A. De Backer have been supported by postdoctoral fellowship grants from the Research Foundation Flanders (FWO). Funding was also received from the European Research Council (starting grant no. COLOURATOM 335078), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 770887), the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N, G.0401.16N) and from the University of Antwerp through GOA project Solarpaint. Funding for the TopSPIN precession system under grant AUHA13009, as well as for the Qu-Ant-EM microscope, is acknowledged from the HERCULES Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (F.R.S.-FNRS). (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; Approved Most recent IF: 2.654
Call Number (down) EMAT @ emat @c:irua:153737UA @ admin @ c:irua:153737 Serial 5064
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Author Amini, M.N.; Altantzis, T.; Lobato, I.; Grzelczak, M.; Sánchez-Iglesias, A.; Van Aert, S.; Liz-Marzán, L.M.; Partoens, B.; Bals, S.; Neyts, E.C.
Title Understanding the Effect of Iodide Ions on the Morphology of Gold Nanorods Type A1 Journal article
Year 2018 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char
Volume 35 Issue 35 Pages 1800051
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The presence of iodide ions during the growth of gold nanorods strongly affects the shape of the final products, which is proposed to be due to selective iodide adsorption on certain crystallographic facets. Therefore, a detailed structural and morphological characterization of the starting rods is crucial toward understanding this effect. Electron tomography is used to determine the crystallographic indices of the lateral facets of gold nanorods, as well as those present at the tips. Based on this information, density functional theory calculations are used to determine the surface and interface energies of the observed facets and provide insight into the relationship between the amount of iodide ions in the growth solution and the final morphology of anisotropic gold nanoparticles.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000441893400002 Publication Date 2018-06-10
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 6 Open Access OpenAccess
Notes This work was supported by the European Research Council (grant 335078 COLOURATOM to S.B.). T.A., S.V.A. S.B. and E.C.N., acknowledge funding from the Research Foundation Flanders (FWO, Belgium), through project funding (G.0218.14N and G.0369.15N) and a postdoctoral grant to T.A. L.M.L.-M. and M.G. acknowledge funding from the Spanish Ministerio de Economía y Competitividad (grant MAT2013-46101-R). Mozhgan N. Amini and Thomas Altantzis contributed equally to this work. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ecas_sara Approved Most recent IF: 4.474
Call Number (down) EMAT @ emat @c:irua:152998UA @ admin @ c:irua:152998 Serial 5010
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Author Peters, J.L.; Altantzis, T.; Lobato, I.; Jazi, M.A.; van Overbeek, C.; Bals, S.; Vanmaekelbergh, D.; Sinai, S.B.
Title Mono- and Multilayer Silicene-Type Honeycomb Lattices by Oriented Attachment of PbSe Nanocrystals: Synthesis, Structural Characterization, and Analysis of the Disorder Type A1 Journal article
Year 2018 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 30 Issue 30 Pages 4831-4837
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Nanocrystal (NC) solids are commonly prepared from nonpolar organic NC suspensions. In many cases, the capping on the NC surface is preserved and forms a barrier between the NCs. More recently, superstructures with crystalline connections between the NCs, implying the removal of the capping, have been reported, too. Here, we present large-scale uniform superstructures of attached PbSe NCs with a silicene-type honeycomb geometry, resulting from solvent evaporation under nearly reversible conditions. We also prepared multilayered silicene honeycomb structures by using larger amounts of PbSe NCs. We show that the two-dimensional silicene superstructures can be seen as a crystallographic slice from a 3-D simple cubic structure. We describe the disorder in the silicene lattices in terms of the nanocrystals position and their atomic alignment. The silicene honeycomb sheets are large enough to be used in transistors and optoelectronic devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000440105500042 Publication Date 2018-07-24
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 33 Open Access OpenAccess
Notes The authors acknowledge funding from the European Commission (Grant EUSMI 731019). S.B. acknowledges funding from the European Research Council (Grant 335078 COLOURATOM). T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO). The authors acknowledge financial support from the European Commission under the Horizon 2020 Programme by means of the Grant Agreement No. 731019 EUSMI. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ecas_sara Approved Most recent IF: 9.466
Call Number (down) EMAT @ emat @c:irua:152997UA @ admin @ c:irua:152997 Serial 5011
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Author van den Bos, K.H.W.; Altantzis, T.; De Backer, A.; Van Aert, S.; Bals, S.
Title Recent breakthroughs in scanning transmission electron microscopy of small species Type A1 Journal article
Year 2018 Publication Advances in Physics: X Abbreviated Journal Advances in Physics: X
Volume 3 Issue 3 Pages 1480420
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Over the last decade, scanning transmission electron microscopy has become one of the most powerful tools to characterise nanomaterials at the atomic scale. Often, the ultimate goal is to retrieve the three-dimensional structure, which is very challenging since small species are typically sensitive to electron irradiation. Nevertheless, measuring individual atomic positions is crucial to understand the relation between the structure and physicochemical properties of these (nano)materials. In this review, we highlight the latest approaches that are available to reveal the 3D atomic structure of small species. Finally, we will provide an outlook and will describe future challenges where the limits of electron microscopy will be pushed even further.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000441619500001 Publication Date 2018-08-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2374-6149 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 8 Open Access OpenAccess
Notes This work was supported by the Research Foundation Flanders (FWO, Belgium) under Grant G.0368.15N, G.0369.15N, and G.0267.18N, by personal FWO Grants to K. H. W. van den Bos, T. Altantzis, and A. De Backer, and the European Research Council under Grant 335078 COLOURATOM to S. Bals. The authors would like to thank the colleagues who have contributed to this work over the years, including A. M. Abakumov, K. J. Batenburg, E. Countiño-Gonzalez, C. de Mello Donega, R. Erni, J. J. Geuchies, B. Goris, J. Hofkens, L. Jones, P. Lievens, L. M. Liz-Marzán, I. Lobato, G. T. Martinez, P. D. Nellist, B. Partoens, M. B. J. Roeffaers, M.D. Rossell, B. Schoeters, M. J. Van Bael, W. van der Stam, M. van Huis, G. Van Tendeloo, D. Vanmaekelbergh, and N. Winckelmans. (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; Approved Most recent IF: NA
Call Number (down) EMAT @ emat @c:irua:152820UA @ admin @ c:irua:152820 Serial 5007
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Author Barreca, D.; Carraro, G.; Maccato, C.; Altantzis, T.; Kaunisto, K.; Gasparotto, A.
Title Controlled Growth of Supported ZnO Inverted Nanopyramids with Downward Pointing Tips Type A1 Journal article
Year 2018 Publication Crystal growth & design Abbreviated Journal Cryst Growth Des
Volume Issue Pages acs.cgd.8b00198
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High purity porous ZnO nanopyramids with controllable properties are grown on their tips on

Si(100) substrates by means of a catalyst-free vapor phase deposition route in a wet oxygen

reaction environment. The system degree of preferential [001] orientation, as well as

nanopyramid size, geometrical shape and density distribution, can be finely tuned by varying the

growth temperature between 300 and 400°C, whereas higher temperatures lead to more compact

systems with a three-dimensional (3D) morphology. A growth mechanism of the obtained ZnO

nanostructures based on a self-catalytic vapor-solid (VS) mode is proposed, in order to explain

the evolution of nanostructure morphologies as a function of the adopted process conditions. The

results obtained by a thorough chemico-physical characterization enable to get an improved

control over the properties of ZnO nanopyramids grown by this technique. Taken together, they

are of noticeable importance not only for fundamental research on ZnO nanomaterials with

controlled nano-organization, but also to tailor ZnO functionalities in view of various potential

applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000429508200073 Publication Date 2018-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1528-7483 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.055 Times cited 6 Open Access OpenAccess
Notes This work has been supported by Padova University ex-60% 2015–2017, P-DiSC #03BIRD2016-UNIPD projects and ACTION post-doc fellowship. T. A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). Thanks are also due to Dr. Rosa Calabrese (Department of Chemical Sciences, Padova University, Italy) and to Dr. T.-P. Ruoko (Department of Chemistry and Bioengineering, Tampere University of Technology, Finland) for skilful technical support. Approved Most recent IF: 4.055
Call Number (down) EMAT @ emat @c:irua:149514 Serial 4904
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Author Yang, Z.; Altantzis, T.; Bals, S.; Tendeloo, G.V.; Pileni, M.-P.
Title Do Binary Supracrystals Enhance the Crystal Stability? Type A1 Journal article
Year 2018 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 122 Issue 122 Pages 13515-13521
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We study the oxygen thermal stability of two binary

systems. The larger particles are magnetic amorphous Co (7.2 nm) or

Fe3O4 (7.5 nm) nanocrystals, whereas the smaller ones (3.7 nm) are

Au nanocrystals. The nanocrystal ordering as well as the choice of the

magnetic nanoparticles very much influence the stability of the binary

system. A perfect crystalline structure is obtained with the Fe3O4/Au

binary supracrystals. For the Co/Au binary system, oxidation of Co

results in the chemical transformation from Co to CoO, where the size

of the amorphous Co nanoparticles increases from 7.2 to 9.8 nm in

diameter. During the volume expansion of the Co nanoparticles, Au

nanoparticles within the binary assemblies coalesce and are at the

origin of the instability of the binary nanoparticle supracrystals. On the

other hand, for the Fe3O4/Au binary system, the oxidation of Fe3O4 to

γ-Fe2O3 does not lead to a size change of the nanoparticles, which

maintains the stability of the binary nanoparticle supracrystals. A similar behavior is observed for an AlB2-type Co−Ag binary

system: The crystalline structure is maintained, whereas in disordered assemblies, coalescence of Ag nanocrystals is observed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000437811500035 Publication Date 2018-01-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 5 Open Access OpenAccess
Notes The research leading to these results has been supported by an Advanced Grant of the European Research Council under Grant 267129. The authors appreciate financial support by the European Union under the Framework 7 program under a contract for an Integrated Infrastructure Initiative (Reference No. 262348 ESMI). S.B. acknowledges funding from ERC Starting Grant COLOURATOMS (335078). T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ecas_sara Approved Most recent IF: 4.536
Call Number (down) EMAT @ emat @c:irua:149388UA @ admin @ c:irua:149388 Serial 4812
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Author Winckelmans, N.; Altantzis, T.; Grzelczak, M.; Sánchez-Iglesias, A.; Liz-Marzán, L.M.; Bals, S.
Title Multimode Electron Tomography as a Tool to Characterize the Internal Structure and Morphology of Gold Nanoparticles Type A1 Journal article
Year 2018 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 122 Issue 122 Pages 13522-13528
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Three dimensional (3D) characterization of structural defects in nanoparticles by transmission electron microscopy is far from straightforward. We propose the use of a dose-efficient approach, so-called multimode tomography, during which tilt series of low and high angle annular dark field scanning transmission electron microscopy projection images are acquired simultaneously. In this manner, not only reliable information can be obtained concerning the shape of the nanoparticles, but also the twin planes can be clearly visualized in 3D. As an example, we demonstrate the application of this approach to identify the position of the seeds with respect to the twinning planes in anisotropic gold nanoparticles synthesized using a seed mediated growth approach.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000437811500036 Publication Date 2018-01-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 23 Open Access OpenAccess
Notes S.B. and N.W. acknowledge funding from the European Research Council under the Seventh Framework Program (FP7), ERC Grant No. 335078 COLOURATOM. S.B. and T.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0369.15N and G.0218.14N) and a postdoctoral research grant to T.A. L.M.L.-M. and M.G. acknowledge funding from the Spanish Ministerio de Economía y Competitividad (grant MAT2013-46101-R). L.M.L.-M. and S.B. acknowledge funding from the European Commission (grant EUSMI 731019). (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); saraecas; ECAS_Sara; Approved Most recent IF: 4.536
Call Number (down) EMAT @ emat @c:irua:148164UA @ admin @ c:irua:148164 Serial 4807
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Author Udayabhaskararao, T.; Altantzis, T.; Houben, L.; Coronado-Puchau, M.; Langer, J.; Popovitz-Biro, R.; Liz-Marzán, L.M.; Vuković, L.; Král, P.; Bals, S.; Klajn, R.
Title Tunable porous nanoallotropes prepared by post-assembly etching of binary nanoparticle superlattices Type A1 Journal article
Year 2017 Publication Science Abbreviated Journal Science
Volume 358 Issue 358 Pages 514-518
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Self-assembly of inorganic nanoparticles has been used to prepare hundreds of different colloidal crystals, but almost invariably with the restriction that the particles must be densely packed. Here,we show that non–close-packed nanoparticle arrays can be fabricated through the selective removal of one of two components comprising binary nanoparticle superlattices. First, a variety of binary nanoparticle superlattices were prepared at the liquid-air interface, including several arrangements that were previously unknown. Molecular dynamics simulations revealed the particular role of the liquid in templating the formation of superlattices not achievable through self-assembly in bulk solution. Second, upon stabilization, all of these binary superlattices could be transformed into distinct “nanoallotropes”—nanoporous materials having the same chemical composition but differing in their nanoscale architectures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000413757500043 Publication Date 2017-10-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0036-8075 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 37.205 Times cited 113 Open Access OpenAccess
Notes This work was supported by the European Research Council (grants 336080 CONFINEDCHEM to R.K. and 335078 COLOURATOM to S.B.), the Rothschild Caesarea Foundation (R.K.), the NSF (Division of Materials Research, grant 1506886) (P.K.), the European Commission (grant EUSMI 731019 to L.M.L.-M. and S.B.), and the startup funding from the University of Texas at El Paso (L.V.). L.M.L.-M. acknowledges funding from the Spanish Ministerio de Economía y Competitividad (grant MAT2013- 46101-R). T.A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. The computer support was provided by the Texas Advanced Computing Center. All data are reported in the main text and supplementary materials. ECAS_Sara (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 37.205
Call Number (down) EMAT @ emat @c:irua:147242UA @ admin @ c:irua:147242 Serial 4770
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Author Kus, M.; Altantzis, T.; Vercauteren, S.; Caretti, I.; Leenaerts, O.; Batenburg, K.J.; Mertens, M.; Meynen, V.; Partoens, B.; Van Doorslaer, S.; Bals, S.; Cool, P.
Title Mechanistic Insight into the Photocatalytic Working of Fluorinated Anatase {001} Nanosheets Type A1 Journal article
Year 2017 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 121 Issue 121 Pages 26275-26286
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Laboratory of adsorption and catalysis (LADCA)
Abstract Anatase nanosheets with exposed {001} facets

have gained increasing interest for photocatalytic applications. To

fully understand the structure-to-activity relation, combined

experimental and computational methods have been exploited.

Anatase nanosheets were prepared under hydrothermal conditions

in the presence of fluorine ions. High resolution scanning

transmission electron microscopy was used to fully characterize

the synthesized material, confirming the TiO2 nanosheet

morphology. Moreover, the surface structure and composition

of a single nanosheet could be determined by annular bright-field

scanning transmission electron microscopy (ABF-STEM) and

STEM electron energy loss spectroscopy (STEM-EELS). The photocatalytic activity was tested for the decomposition of organic

dyes rhodamine 6G and methyl orange and compared to a reference TiO2 anatase sample. The anatase nanosheets with exposed

{001} facets revealed a significantly lower photocatalytic activity compared to the reference. In order to understand the

mechanism for the catalytic performance, and to investigate the role of the presence of F−, light-induced electron paramagnetic

resonance (EPR) experiments were performed. The EPR results are in agreement with TEM, proving the presence of Ti3+

species close to the surface of the sample and allowing the analysis of the photoinduced formation of paramagnetic species.

Further, ab initio calculations of the anisotropic effective mass of electrons and electron holes in anatase show a very high effective

mass of electrons in the [001] direction, having a negative impact on the mobility of electrons toward the {001} surface and thus

the photocatalysis. Finally, motivated by the experimental results that indicate the presence of fluorine atoms at the surface, we

performed ab initio calculations to determine the position of the band edges in anatase slabs with different terminations of the

{001} surface. The presence of fluorine atoms near the surface is shown to strongly shift down the band edges, which indicates

another reason why it can be expected that the prepared samples with a large amount of {001} surface, but with fluorine atoms

near the surface, show only a low photocatalytic activity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000417228500017 Publication Date 2017-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 20 Open Access OpenAccess
Notes The authors acknowledge the University of Antwerp for financial support in the frame of a GOA project. S.B. acknowledges funding from the European Research Council under the Seventh Framework Program (FP7), ERC Grant No. 335078 COLOURATOM. S.V.D. and V.M. acknowledge funding from the Fund for Scientific Research-Flanders (G.0687.13). T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); saraecas; ECAS_Sara; Approved Most recent IF: 4.536
Call Number (down) EMAT @ emat @c:irua:147240UA @ admin @ c:irua:147240 Serial 4771
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Author Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Altantzis, T.; Sada, C.; Kaunisto, K.; Ruoko, T.-P.; Bals, S.
Title Vapor Phase Fabrication of Nanoheterostructures Based on ZnO for Photoelectrochemical Water Splitting Type A1 Journal article
Year 2017 Publication Advanced Materials Interfaces Abbreviated Journal Adv Mater Interfaces
Volume 4 Issue 4 Pages 1700161
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Nanoheterostructures based on metal oxide semiconductors have emerged

as promising materials for the conversion of sunlight into chemical energy.

In the present study, ZnO-based nanocomposites have been developed by

a hybrid vapor phase route, consisting in the chemical vapor deposition

of ZnO systems on fluorine-doped tin oxide substrates, followed by the

functionalization with Fe2O3 or WO3 via radio frequency-sputtering. The

target systems are subjected to thermal treatment in air both prior and after

sputtering, and their properties, including structure, chemical composition,

morphology, and optical absorption, are investigated by a variety of characterization

methods. The obtained results evidence the formation of highly

porous ZnO nanocrystal arrays, conformally covered by an ultrathin Fe2O3

or WO3 overlayer. Photocurrent density measurements for solar-triggered

water splitting reveal in both cases a performance improvement with respect

to bare zinc oxide, that is mainly traced back to an enhanced separation of

photogenerated charge carriers thanks to the intimate contact between the

two oxides. This achievement can be regarded as a valuable result in view of

future optimization of similar nanoheterostructured photoanodes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000411525700007 Publication Date 2017-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2196-7350 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.279 Times cited 30 Open Access OpenAccess
Notes The authors kindly acknowledge the financial support under Padova University ex-60% 2013–2016, P-DiSC #SENSATIONAL BIRD2016- UNIPD projects and the post-doc fellowship ACTION. S.B. acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078) and T.A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. Many thanks are also due to Dr. Rosa Calabrese (Department of Chemistry, Padova University, Italy) for experimental assistance. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; Approved Most recent IF: 4.279
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Author González-Rubio, G.; de Oliveira, T.M.; Altantzis, T.; La Porta, A.; Guerrero-Martínez, A.; Bals, S.; Scarabelli, L.; Liz-Marzán, L.M.
Title Disentangling the effect of seed size and crystal habit on gold nanoparticle seeded growth Type A1 Journal article
Year 2017 Publication Chemical communications Abbreviated Journal Chem Commun
Volume 53 Issue 53 Pages 11360-11363
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Oxidative etching was used to produce gold seeds of different sizes and crystal habits. Following detailed characterization, the seeds were grown under different conditions. Our results bring new insights toward understanding the effect of size and crystallinity on the growth of anisotropic particles, whilst identifying guidelines for the optimisation of new synthetic protocols of predesigned seeds.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000412814900019 Publication Date 2017-09-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-7345 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited 29 Open Access OpenAccess
Notes This work was funded by the Spanish MINECO (grant # MAT2013-46101-R, Ramon y Cajal fellowship to A. G.-M. and FPI fellowship to G. G.-R.). Financial support is acknowledged from the European Commission (EUSMI, 731019). S. B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). T. A. acknowledges a postdoctoral grant from Research Foundation Flanders (FWO, Belgium). ECAS_Sara (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 6.319
Call Number (down) EMAT @ emat @c:irua:146101UA @ admin @ c:irua:146101 Serial 4734
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Author Altantzis, T.; Zanaga, D.; Bals, S.
Title Advanced electron tomography of nanoparticle assemblies Type A1 Journal article
Year 2017 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett
Volume 119 Issue 119 Pages 38001
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Nanoparticle assemblies have attracted enormous scientific interest during the last

years, due to their unique properties compared to those of their building blocks. To understand

the origin of these properties and to establish the connection with their structure, a detailed and

quantitative structural characterization is essential. Transmission electron microscopy has been

widely used to investigate nano-assemblies. However, TEM images only correspond to a twodimensional

projection of a three-dimensional object. Therefore, in order to obtain the necessary

3D structural information electron tomography has to be applied. By means of advanced electron

tomography, both qualitative and quantitative information can be obtained, which can be used

for detailed theoretical studies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000415019400023 Publication Date 2017-10-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0295-5075 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.957 Times cited 8 Open Access OpenAccess
Notes We would like to thank the colleagues who have contributed to this work over the years, including L. M. Liz- Marzan, M. Grzelczak, A. Sanchez-Iglesias, D. Vanmaekelbergh, M. P. Boneschanscher, W. H. Evers, J. J. Geuchies, B. Goris, A. de Backer, S. van Aert, M.-P. Pileni, Z. Yang, K. J. Batenburg, J. Sijbers, F. Bleichrodt, W. J. Palenstijn, A. van Blaaderen, M. A. van Huis, F. M. Peeters, N. Winckelmans and D. Wang. The authors gratefully acknowledge funding from the Research Foundation Flanders (G.0381.16N, G.036915 G.0374.13 and funding of a postdoctoral grant to TA). SB and DZ acknowledge funding from the European Research Council, ERC grant No. 335078 – Colouratom. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); saraecas; ECAS_Sara; Approved Most recent IF: 1.957
Call Number (down) EMAT @ emat @c:irua:146096UA @ admin @ c:irua:146096 Serial 4733
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Author Montanarella, F.; Altantzis, T.; Zanaga, D.; Rabouw, F.T.; Bals, S.; Baesjou, P.; Vanmaekelbergh, D.; van Blaaderen, A.
Title Composite Supraparticles with Tunable Light Emission Type A1 Journal article
Year 2017 Publication ACS nano Abbreviated Journal Acs Nano
Volume 11 Issue 11 Pages 9136-9142
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Robust luminophores emitting light with broadly tunable colors are desirable in many applications such as light-emitting diode (LED)-based lighting, displays, integrated optoelectronics and biology. Nanocrystalline quantum dots with multicolor emission, from core- and shell-localized excitons, as well as solid layers of mixed quantum dots that emit different colors have been proposed. Here, we report on colloidal supraparticles that are composed of three types of Cd(Se,ZnS) core/(Cd,Zn)S shell nanocrystals with emission in the red, green, and blue. The emission of the supraparticles can be varied from pure to composite colors over the entire visible region and finetuned into variable shades of white light by mixing the nanocrystals in controlled proportions. Our approach results in supraparticles with sizes spanning the colloidal domain and beyond that combine versatility and processability with a broad, stable, and tunable emission, promising applications in lighting devices and biological research.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000411918200062 Publication Date 2017-09-26
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 36 Open Access OpenAccess
Notes We thank J. J. Geuchies for help with the optical analysis, W. Vlug for providing silica particles filled with RITC, J. D. Meeldijk for his assistance with SE-STEM measurements, E. B. van der Wee for help with the calculation of the radial distribution functions, and M. van Huis and S. Dussi for very fruitful discussions. This work was supported by the European Comission via the Marie-Sklodowska Curie action Phonsi (H2020-MSCA-ITN-642656). D.V. wishes to thank the Dutch FOM (program DDC13), NWO−CW (Toppunt 718.015.002), and the European Research Council under HORIZON 2020 (grant 692691 FIRSTSTEP) for financial support. A.v.B. and F.M. acknowledge partial funding from the European Research Council under the European Union’s Seventh Framework Programme (FP-2007-2013)/ERC advanced grant agreement 291667: HierarSACol. S.B. and D.Z. acknowledge financial support from the European Research Council (starting grant no. COLOURATOM 335078), and T.A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. ECAS_Sara (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 13.942
Call Number (down) EMAT @ emat @c:irua:146095UA @ admin @ c:irua:146095 Serial 4732
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Author Schnepf, M.J.; Mayer, M.; Kuttner, C.; Tebbe, M.; Wolf, D.; Dulle, M.; Altantzis, T.; Formanek, P.; Förster, S.; Bals, S.; König, T.A.F.; Fery, A.
Title Nanorattles with tailored electric field enhancement Type A1 Journal article
Year 2017 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 9 Issue 9 Pages 9376-9385
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanorattles are metallic core–shell particles with core and shell separated by a dielectric spacer. These

nanorattles have been identified as a promising class of nanoparticles, due to their extraordinary high

electric-field enhancement inside the cavity. Limiting factors are reproducibility and loss of axial symmetry

owing to the movable metal core; movement of the core results in fluctuation of the nanocavity dimensions

and commensurate variations in enhancement factor. We present a novel synthetic approach for

the robust fixation of the central gold rod within a well-defined box, which results in an axisymmetric

nanorattle. We determine the structure of the resulting axisymmetric nanorattles by advanced transmission

electron microscopy (TEM) and small-angle X-ray scattering (SAXS). Optical absorption and scattering

cross-sections obtained from UV-vis-NIR spectroscopy quantitatively agree with finite-difference

time-domain (FDTD) simulations based on the structural model derived from SAXS. The predictions of

high and homogenous field enhancement are evidenced by scanning TEM electron energy loss spectroscopy

(STEM-EELS) measurement on single-particle level. Thus, comprehensive understanding of

structural and optical properties is achieved for this class of nanoparticles, paving the way for photonic

applications where a defined and robust unit cell is crucial.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000405387100015 Publication Date 2017-06-22
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 69 Open Access OpenAccess
Notes This study was funded by the European Research Council under grant Template-assisted assembly of METAmaterials using MECHanical instabilities (METAMECH) ERC-2012-StG 306686. This work was also supported by the Deutsche Forschungsgemeinschaft (DFG) within the Cluster of Excellence ‘Center for Advancing Electronics Dresden’ (cfaed). M. T. wants to acknowledge funding by the Elite Network of Bavaria, the Bavarian Ministry of State according to the Bavarian elite promotion act (BayEFG), as well as the Alexander von Humboldt Foundation for a Feodor-Lynen Research Fellowship. S. B. acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078) and T. A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. We thank Ken Harris from the National Research Council Canada for valuable discussion of the manuscript. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; Approved Most recent IF: 7.367
Call Number (down) EMAT @ emat @ c:irua:144797UA @ admin @ c:irua:144797 Serial 4631
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Author Pulinthanathu Sree, S.; Dendooven, J.; Geerts, L.; Ramachandran, R.K.; Javon, E.; Ceyssens, F.; Breynaert, E.; Kirschhock, C.E.A.; Puers, R.; Altantzis, T.; Van Tendeloo, G.; Bals, S.; Detavernier, C.; Martens, J.A.
Title 3D porous nanostructured platinum prepared using atomic layer deposition Type A1 Journal article
Year 2017 Publication Journal of materials chemistry A : materials for energy and sustainability Abbreviated Journal J Mater Chem A
Volume 5 Issue 5 Pages 19007-19016
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A robust and easy to handle 3D porous platinum structure was created via replicating the 3D channel system

of an ordered mesoporous silica material using atomic layer deposition (ALD) over micrometer distances.

After ALD of Pt in the silica material, the host template was digested using hydrogen fluoride (HF). A fully

connected ordered Pt nanostructure was obtained with morphology and sizes corresponding to that of

the pores of the host matrix, as revealed with high-resolution scanning transmission electron

microscopy and electron tomography. The Pt nanostructure consisted of hexagonal Pt rods originating

from the straight mesopores (11 nm) of the host structure and linking features resulting from Pt

replication of the interconnecting mesopore segments (2–4 nm) present in the silica host structure.

Electron tomography of partial replicas, made by incomplete infilling of Zeotile-4 material with Pt,

provided insight in the connectivity and formation mechanism of the Pt nanostructure by ALD. The Pt

replica was evaluated for its potential use as electrocatalyst for the hydrogen evolution reaction, one of

the half-reactions of water electrolysis, and as microelectrode for biomedical sensing. The Pt replica

showed high activity for the hydrogen evolution reaction and electrochemical characterization revealed

a large impedance improvement in comparison with reference Pt electrodes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000411232100010 Publication Date 2017-06-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7488 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.867 Times cited 9 Open Access OpenAccess
Notes This work was supported by the Flemish government through long-term structural funding (Methusalem) to JAM and FWO for a research project (G0A5417N). JD, TA and FC acknowledge Flemish FWO for a post-doctoral fellowship. S. B. acknowledges funding from ERC Starting Grant COLOURATOMS (335078). (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; Approved Most recent IF: 8.867
Call Number (down) EMAT @ emat @ c:irua:144624 c:irua:144624 c:irua:144624UA @ admin @ c:irua:144624 Serial 4634
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Author De Backer, A.; Jones, L.; Lobato, I.; Altantzis, T.; Goris, B.; Nellist, P.D.; Bals, S.; Van Aert, S.
Title Three-dimensional atomic models from a single projection using Z-contrast imaging: verification by electron tomography and opportunities Type A1 Journal article
Year 2017 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 9 Issue 9 Pages 8791-8798
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In order to fully exploit structure–property relations of nanomaterials, three-dimensional (3D) characterization at the atomic scale is often required. In recent years, the resolution of electron tomography has reached the atomic scale. However, such tomography typically requires several projection images demanding substantial electron dose. A newly developed alternative circumvents this by counting the number of atoms across a single projection. These atom counts can be used to create an initial atomic model with which an energy minimization can be applied to obtain a relaxed 3D reconstruction of the nanoparticle. Here, we compare, at the atomic scale, this single projection reconstruction approach with tomography and find an excellent agreement. This new approach allows for the characterization of beam-sensitive materials or where the acquisition of a tilt series is impossible. As an example, the utility is illustrated by the 3D atomic scale characterization of a nanodumbbell on an in situ heating holder of limited tilt range.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000404614700031 Publication Date 2017-06-09
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 33 Open Access OpenAccess
Notes The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N, G.0368.15N, and WO.010.16N) and postdoctoral grants to T. Altantzis, A. De Backer, and B. Goris. S. Bals acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078). Funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiatieve-I3) is acknowledged. The authors would also like to thank Luis Liz-Marzán, Marek Grzelczak, and Ana Sánchez-Iglesias for sample provision. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; Approved Most recent IF: 7.367
Call Number (down) EMAT @ emat @ c:irua:144436UA @ admin @ c:irua:144436 Serial 4617
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Author van der Stam, W.; Geuchies, J.J.; Altantzis, T.; van den Bos, K.H.W.; Meeldijk, J.D.; Van Aert, S.; Bals, S.; Vanmaekelbergh, D.; de Mello Donega, C.
Title Highly Emissive Divalent-Ion-Doped Colloidal CsPb1–xMxBr3Perovskite Nanocrystals through Cation Exchange Type A1 Journal article
Year 2017 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 139 Issue 139 Pages 4087-4097
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition tuning through topotactic

anion exchange. In contrast, property control by cation exchange is still underdeveloped for colloidal CsPbX3 NCs. Here, we present a method that allows partial cation exchange in colloidal CsPbBr3 NCs, whereby Pb2+ is exchanged for several isovalent cations, resulting in doped CsPb1−xMxBr3 NCs (M= Sn2+, Cd2+, and Zn2+; 0 < x ≤ 0.1), with preservation of the original NC shape. The size of the parent NCs is also preserved in the product NCs, apart from a small (few

%) contraction of the unit cells upon incorporation of the guest cations. The partial Pb2+ for M2+ exchange leads to a blue-shift of the optical spectra, while maintaining the high photoluminescence quantum yields (>50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. The blue-shift in the optical spectra is attributed to the lattice contraction that accompanies the Pb2+ for M2+ cation exchange and is observed to scale linearly with the lattice contraction. This work opens up new possibilities to engineer the properties of halide perovskite NCs, which to date are demonstrated to be the only known

system where cation and anion exchange reactions can be sequentially combined while preserving the original NC shape, resulting in compositionally diverse perovskite NCs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000397477700027 Publication Date 2017-03-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited 535 Open Access OpenAccess
Notes W.v.d.S. and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under grant number ECHO.712.012.001. J.J.G. and D.V. acknowledge financial support from the Debye Graduate program. S.B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). K.H.W.v.d.B., S.B., S.V.A. and T.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0368.15N, G.0369.15N), a Ph.D. grant to K.H.W.v.d.B, and a postdoctoral research grant to T.A. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara Approved Most recent IF: 13.858
Call Number (down) EMAT @ emat @ c:irua:141754UA @ admin @ c:irua:141754 Serial 4482
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Author Sánchez-Iglesias, A.; Winckelmans, N.; Altantzis, T.; Bals, S.; Grzelczak, M.; Liz-Marzán, L.M.
Title High-Yield Seeded Growth of Monodisperse Pentatwinned Gold Nanoparticles through Thermally Induced Seed Twinning Type A1 Journal article
Year 2016 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 139 Issue 139 Pages 107-110
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We show here that thermal treatment of small seeds results in extensive twinning and a subsequent drastic yield improvement (>85%) in the formation of pentatwinned nanoparticles, with pre-selected morphology (nanorods, bipyramids and decahedra) and aspect ratio. The “quality” of the seeds thus defines the yield of the obtained nanoparticles, which in the case of nanorods avoids the need for additives such as Ag+ ions. This modified seeded growth method also improves reproducibility, as the seeds can be stored for extended periods of time without compromising the quality of the final nanoparticles. Additionally, minor modification of the seeds with Pd allows their localization within the final particles, which opens new avenues toward mechanistic studies. All together, these results represent a paradigm shift in anisotropic gold nanoparticle synthesis.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000392036900025 Publication Date 2016-12-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited 267 Open Access OpenAccess
Notes Financial support is acknowledged from the European Research Council through ERC Advanced Grant Plasmaquo and the ERC Starting Grant COLOURATOM. T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara Approved Most recent IF: 13.858
Call Number (down) EMAT @ emat @ c:irua:139018UA @ admin @ c:irua:139018 Serial 4339
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