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Author | Wu, L.; Kolmeijer, K.E.; Zhang, Y.; An, H.; Arnouts, S.; Bals, S.; Altantzis, T.; Hofmann, J.P.; Costa Figueiredo, M.; Hensen, E.J.M.; Weckhuysen, B.M.; van der Stam, W. | ||||
Title | Stabilization effects in binary colloidal Cu and Ag nanoparticle electrodes under electrochemical CO₂ reduction conditions | Type | A1 Journal article | ||
Year | 2021 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 13 | Issue | 9 | Pages | 4835-4844 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Nanoparticle modified electrodes constitute an attractive way to tailor-make efficient carbon dioxide (CO2) reduction catalysts. However, the restructuring and sintering processes of nanoparticles under electrochemical reaction conditions not only impedes the widespread application of nanoparticle catalysts, but also misleads the interpretation of the selectivity of the nanocatalysts. Here, we colloidally synthesized metallic copper (Cu) and silver (Ag) nanoparticles with a narrow size distribution (<10%) and utilized them in electrochemical CO2 reduction reactions. Monometallic Cu and Ag nanoparticle electrodes showed severe nanoparticle sintering already at low overpotential of -0.8 V vs. RHE, as evidenced by ex situ SEM investigations, and potential-dependent variations in product selectivity that resemble bulk Cu (14% for ethylene at -1.3 V vs. RHE) and Ag (69% for carbon monoxide at -1.0 V vs. RHE). However, by co-deposition of Cu and Ag nanoparticles, a nanoparticle stabilization effect was observed between Cu and Ag, and the sintering process was greatly suppressed at CO2 reducing potentials (-0.8 V vs. RHE). Furthermore, by varying the Cu/Ag nanoparticle ratio, the CO2 reduction reaction (CO2RR) selectivity towards methane (maximum of 20.6% for dense Cu-2.5-Ag-1 electrodes) and C-2 products (maximum of 15.7% for dense Cu-1-Ag-1 electrodes) can be tuned, which is attributed to a synergistic effect between neighbouring Ag and Cu nanoparticles. We attribute the stabilization of the nanoparticles to the positive enthalpies of Cu-Ag solid solutions, which prevents the dissolution-redeposition induced particle growth under CO2RR conditions. The observed nanoparticle stabilization effect enables the design and fabrication of active CO2 reduction nanocatalysts with high durability. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000628024200011 | Publication Date | 2021-02-22 | |
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 | 24 | Open Access | OpenAccess |
Notes | This work is funded by the Strategic UU-TU/e Alliance project ‘Joint Centre for Chemergy Research’ (budget holder B. M. W.). S. B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO). S. A. and T. A. acknowledge funding from the University of Antwerp Research fund (BOF). We thank Eric Hellebrand (Faculty of Geosciences, Utrecht University) for the assistance in SEM measurements. Dr Ramon Oord (ARC Chemical Building Blocks Consortium, Faculty of Science, Utrecht University) is acknowledged for assisting with the grazing incidence XRD measurements; sygma | Approved | Most recent IF: 7.367 | ||
Call Number | UA @ admin @ c:irua:176723 | Serial | 6737 | ||
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Author | Duarte, M.; Daems, N.; Hereijgers, J.; Arenas Esteban, D.; Bals, S.; Breugelmans, T. | ||||
Title | Enhanced CO2 electroreduction with metal-nitrogen-doped carbons in a continuous flow reactor | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Co2 Utilization | Abbreviated Journal | J Co2 Util |
Volume | 50 | Issue | Pages | 101583-12 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | As part of a mitigation and adaptation approach to increasing carbon dioxide atmospheric concentrations, we report superior performance of various metal-nitrogen-doped carbon catalysts, synthesized using an easily up-scalable method, for the electrochemical reduction to carbon monoxide and/or formate at industrially relevant current densities up to 200 mAcm−2. Altering the embedded transition metal (i.e. Sn, Co, Fe, Mn and Ni) allowed to tune the selectivity towards the desired product. Mn-N-C and Fe-N-C performance was compromised by its high CO* binding energy, while Co-N-C catalyzed preferentially the HER. Ni-N-C and Sn-N-C revealed to be promising electrocatalysts, the latter being evaluated for the first time in a flow reactor. A productivity of 589 L CO m-2 h-1 at -1.39 VRHE with Ni-N-C and 751 g HCOO- m-2 h-1 at -1.47 VRHE with Sn-N-C was achieved with no signs of degradation detected after 24 h of operation at industrially relevant current densities (100 mAcm−2). Stable operation at 200 mAcm−2 led to turnover frequencies for the production of carbon products of up to 5176 h-1. These enhanced productivities, in combination with high stability, constitute an essential step towards the scalability and ultimately towards the economical valorization of CO2 electrolyzers using metal-containing nitrogen-doped catalysts. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000670316000002 | Publication Date | 2021-05-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2212-9820 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.292 | Times cited | 14 | Open Access | OpenAccess |
Notes | The authors acknowledge sponsoring from the Research Foundation – Flanders (FWO) in the frame of a post-doctoral grant (12Y3919N – ND). This project was co-funded by the Interreg 2 Seas-Program 2014-2020, co-financed by the European Fund for Regional Development in the frame of subsidiary contract nr. 2S03-019. This work was further performed in the framework of the Catalisti MOT project D2M (“Dioxide to Monoxide (D2M): Innovative catalysis for CO2 to CO conversion”). We thank Lien Pacquets for analyzing the samples with SEM-EDX, Saskia Defoss´e for helping with the N2 physisorption measurements and Kitty Baert (VUB) for analyzing the samples with XPS and Raman. | Approved | Most recent IF: 4.292 | ||
Call Number | UA @ admin @ c:irua:178151 | Serial | 6779 | ||
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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. |
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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 | EMAT @ emat @c:irua:179781 | Serial | 6805 | ||
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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 | EMAT @ emat @c:irua:183285 | Serial | 6817 | ||
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Author | Coeck, R.; Meeprasert, J.; Li, G.; Altantzis, T.; Bals, S.; Pidko, E.A.; De Vos, D.E. | ||||
Title | Gold and silver-catalyzed reductive amination of aromatic carboxylic acids to benzylic amines | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 11 | Issue | 13 | Pages | 7672-7684 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | The reductive amination of benzoic acid and its derivatives would be an effective addition to current synthesis methods for benzylamine. However, with current technology it is very difficult to keep the aromaticity intact when starting from benzoic acid, and salt wastes are often generated in the process. Here, we report a heterogeneous catalytic system for such a reductive amination, requiring solely H-2 and NH3 as the reactants. The Ag/TiO2 or Au/TiO2 catalysts can be used multiple times, and very little noble metal is required, only 0.025 mol % Au. The catalysts are bifunctional: the support catalyzes the dehydration of both the ammonium carboxylate to the amide and of the amide to the nitrile, while the sites at the metal-support interface promote the hydrogenation of the in situ generated nitrile. Yields of up to 92% benzylamine were obtained. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000670659900005 | Publication Date | 2021-06-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | 16 | Open Access | OpenAccess |
Notes | R.C. thanks the FWO for his SB PhD fellowship. D.E.D.V. acknowledges FWO for research project funding, as well as KU Leuven for funding in the Metusalem program Casas. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO). T.A. acknowledges funding from the University of Antwerp Research fund (BOF). E.A.P. acknowledges the support from the European Research Council (ERC Consolidator grant #725686 DeliCAT). J.M. acknowledges financial support through the Royal Thai Government Scholarship. DFT calculations on SURFsara supercomputer facilities were performed with support from the Netherlands Organization for Scientific Research (NWO).; sygmaSB | Approved | Most recent IF: 10.614 | ||
Call Number | UA @ admin @ c:irua:179851 | Serial | 6840 | ||
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Author | Choukroun, D.; Pacquets, L.; Li, C.; Hoekx, S.; Arnouts, S.; Baert, K.; Hauffman, T.; Bals, S.; Breugelmans, T. | ||||
Title | Mapping composition–selectivity relationships of supported sub-10 nm Cu–Ag nanocrystals for high-rate CO₂ electroreduction | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 15 | Issue | 9 | Pages | 14858-14872 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Colloidal Cu–Ag nanocrystals measuring less than 10 nm across are promising candidates for integration in hybrid CO2 reduction reaction (CO2RR) interfaces, especially in the context of tandem catalysis and selective multicarbon (C2–C3) product formation. In this work, we vary the synthetic-ligand/copper molar ratio from 0.1 to 1.0 and the silver/copper atomic ratio from 0 to 0.7 and study the variations in the nanocrystals’ size distribution, morphology and reactivity at rates of ≥100 mA cm–2 in a gas-fed recycle electrolyzer operating under neutral to mildly basic conditions (0.1–1.0 M KHCO3). High-resolution electron microscopy and spectroscopy are used in order to characterize the morphology of sub-10 nm Cu–Ag nanodimers and core–shells and to elucidate trends in Ag coverage and surface composition. It is shown that Cu–Ag nanocrystals can be densely dispersed onto a carbon black support without the need for immediate ligand removal or binder addition, which considerably facilitates their application. Although CO2RR product distribution remains an intricate function of time, (kinetic) overpotential and processing conditions, we nevertheless conclude that the ratio of oxygenates to hydrocarbons (which depends primarily on the initial dispersion of the nanocrystals and their composition) rises 3-fold at moderate Ag atom % relative to Cu NCs-based electrodes. Finally, the merits of this particular Cu–Ag/C system and the recycling reactor employed are utilized to obtain maximum C2–C3 partial current densities of 92–140 mA cm–2 at −1.15 VRHE and liquid product concentrations in excess of 0.05 wt % in 1 M KHCO3 after short electrolysis periods. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000703553600082 | Publication Date | 2021-08-24 | |
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 | 25 | Open Access | OpenAccess |
Notes | D.C. acknowledges Thomas Kenis for configuring the analytical instrumentation (HPLC/GC-FID/ICP-MS), Hannelore Andries for assistance with ICP-MS measurements, and Dr. Saeid Pourbabak and Dr. Tine Derez for assistance with Cu sputtering. L.P. was supported by Research Foundation of Flanders (FWO 1S56920N). S.B. acknowledges financial support from ERC Consolidator grant number 815128 REALNANO. S.B. and T.B. acknowledge financial support from the university research fund (BOF-GOA-PS ID no. 33928).; sygmaSB | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:180305 | Serial | 6844 | ||
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Author | Wang, D.; van der Wee, E.B.; Zanaga, D.; Altantzis, T.; Wu, Y.; Dasgupta, T.; Dijkstra, M.; Murray, C.B.; Bals, S.; van Blaaderen, A. | ||||
Title | Quantitative 3D real-space analysis of Laves phase supraparticles | Type | A1 Journal article | ||
Year | 2021 | Publication | Nature Communications | Abbreviated Journal | Nat Commun |
Volume | 12 | Issue | 1 | Pages | 3980 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | 3D real-space analysis of thick nanoparticle crystals is non-trivial. Here, the authors demonstrate the structural analysis of a bulk-like Laves phase by imaging an off-stoichiometric binary mixture of hard-sphere-like nanoparticles in spherical confinement by electron tomography, enabling defect analysis on the single-particle level. Assembling binary mixtures of nanoparticles into crystals, gives rise to collective properties depending on the crystal structure and the individual properties of both species. However, quantitative 3D real-space analysis of binary colloidal crystals with a thickness of more than 10 layers of particles has rarely been performed. Here we demonstrate that an excess of one species in the binary nanoparticle mixture suppresses the formation of icosahedral order in the self-assembly in droplets, allowing the study of bulk-like binary crystal structures with a spherical morphology also called supraparticles. As example of the approach, we show single-particle level analysis of over 50 layers of Laves phase binary crystals of hard-sphere-like nanoparticles using electron tomography. We observe a crystalline lattice composed of a random mixture of the Laves phases. The number ratio of the binary species in the crystal lattice matches that of a perfect Laves crystal. Our methodology can be applied to study the structure of a broad range of binary crystals, giving insights into the structure formation mechanisms and structure-property relations of nanomaterials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000687320200032 | Publication Date | 2021-06-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 10 | Open Access | OpenAccess |
Notes | M. Hermes is sincerely thanked for providing interactive views of the structures in this work. The authors thank I. Lobato, S. Dussi, L. Filion, E. Boattini, S. Paliwal, B. van der Meer and X. Xie for fruitful discussions. D.W., E.B.v.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. T.D. and M.D. acknowledge financial support from the Industrial Partnership Program, “Computational Sciences for Energy Research” (Grant no. 13CSER025), of the Netherlands Organization for Scientific Research (NWO), which was co-financed by Shell Global Solutions International B.V. S.B. acknowledges financial support from ERC Consolidator Grant No. 815128 REALNANO. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). C.B.M and Y.W. acknowledge support for materials synthesis from the Office of Naval Research Multidisciplinary University Research Initiative Award ONR N00014-18-1-2497. The authors acknowledge EM Square center at Utrecht University for the access to the microscopes.; sygmaSB | Approved | Most recent IF: 12.124 | ||
Call Number | UA @ admin @ c:irua:181662 | Serial | 6845 | ||
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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. | ||||
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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 | EMAT @ emat @c:irua:184794 | Serial | 6903 | ||
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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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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 | EMAT @ emat @c:irua:185224 | Serial | 6904 | ||
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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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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 | EMAT @ emat @c:irua:189061 | Serial | 7076 | ||
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Author | Monai, M.; Jenkinson, K.; Melcherts, A.E.M.; Louwen, J.N.; Irmak, E.A.; Van Aert, S.; Altantzis, T.; Vogt, C.; van der Stam, W.; Duchon, T.; Smid, B.; Groeneveld, E.; Berben, P.; Bals, S.; Weckhuysen, B.M. | ||||
Title | Restructuring of titanium oxide overlayers over nickel nanoparticles during catalysis | Type | A1 Journal article | ||
Year | 2023 | Publication | Science | Abbreviated Journal | |
Volume | 380 | Issue | 6645 | Pages | 644-651 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Reducible supports can affect the performance of metal catalysts by the formation of suboxide overlayers upon reduction, a process referred to as the strong metal-support interaction (SMSI). A combination of operando electron microscopy and vibrational spectroscopy revealed that thin TiOx overlayers formed on nickel/titanium dioxide catalysts during 400 degrees C reduction were completely removed under carbon dioxide hydrogenation conditions. Conversely, after 600 degrees C reduction, exposure to carbon dioxide hydrogenation reaction conditions led to only partial reexposure of nickel, forming interfacial sites in contact with TiOx and favoring carbon-carbon coupling by providing a carbon species reservoir. Our findings challenge the conventional understanding of SMSIs and call for more-detailed operando investigations of nanocatalysts at the single-particle level to revisit static models of structure-activity relationships. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000999020900010 | Publication Date | 2023-05-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0036-8075; 1095-9203 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 56.9 | Times cited | 29 | Open Access | OpenAccess |
Notes | This work was supported by BASF and NWO CHIPP (research grant to B.M.W.); the MCEC NWO Gravitation Program (B.M.W.); the ARC-CBBC NWO Program (B.M.W.); the European Research Council (grant 770887 PICOMETRICS to S.V.A.); and the European Research Council (grant 815128 REALNANO to S.B.). | Approved | Most recent IF: 56.9; 2023 IF: 37.205 | ||
Call Number | UA @ admin @ c:irua:197432 | Serial | 8923 | ||
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Author | Van den Hoek, J.; Daems, N.; Arnouts, S.; Hoekx, S.; Bals, S.; Breugelmans, T. | ||||
Title | Improving stability of CO₂ electroreduction by incorporating Ag NPs in N-doped ordered mesoporous carbon structures | Type | A1 Journal article | ||
Year | 2024 | Publication | ACS applied materials and interfaces | Abbreviated Journal | |
Volume | 16 | Issue | 6 | Pages | 6931-6947 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | The electroreduction of carbon dioxide (eCO2RR) to CO using Ag nanoparticles as an electrocatalyst is promising as an industrial carbon capture and utilization (CCU) technique to mitigate CO2 emissions. Nevertheless, the long-term stability of these Ag nanoparticles has been insufficient despite initial high Faradaic efficiencies and/or partial current densities. To improve the stability, we evaluated an up-scalable and easily tunable synthesis route to deposit low-weight percentages of Ag nanoparticles (NPs) on and into the framework of a nitrogen-doped ordered mesoporous carbon (NOMC) structure. By exploiting this so-called nanoparticle confinement strategy, the nanoparticle mobility under operation is strongly reduced. As a result, particle detachment and agglomeration, two of the most pronounced electrocatalytic degradation mechanisms, are (partially) blocked and catalyst durability is improved. Several synthesis parameters, such as the anchoring agent, the weight percentage of Ag NPs, and the type of carbonaceous support material, were modified in a controlled manner to evaluate their respective impact on the overall electrochemical performance, with a strong emphasis on operational stability. The resulting powders were evaluated through electrochemical and physicochemical characterization methods, including X-ray diffraction (XRD), N2-physisorption, Inductively coupled plasma mass spectrometry (ICP-MS), scanning electron microscopy (SEM), SEM-energy-dispersive X-ray spectroscopy (SEM-EDS), high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), STEM-EDS, electron tomography, and X-ray photoelectron spectroscopy (XPS). The optimized Ag/soft-NOMC catalysts showed both a promising selectivity (∼80%) and stability compared with commercial Ag NPs while decreasing the loading of the transition metal by more than 50%. The stability of both the 5 and 10 wt % Ag/soft-NOMC catalysts showed considerable improvements by anchoring the Ag NPs on and into a NOMC framework, resulting in a 267% improvement in CO selectivity after 72 h (despite initial losses) compared to commercial Ag NPs. These results demonstrate the promising strategy of anchoring Ag NPs to improve the CO selectivity during prolonged experiments due to the reduced mobility of the Ag NPs and thus enhanced stability. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001158812100001 | Publication Date | 2023-12-21 | |
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 | Not_Open_Access: Available from 21.06.2024 | |
Notes | Approved | Most recent IF: 9.5; 2024 IF: 7.504 | |||
Call Number | UA @ admin @ c:irua:202309 | Serial | 9045 | ||
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Author | Hoekx, S.; Daems, N.; Arenas Esteban, D.; Bals, S.; Breugelmans, T. | ||||
Title | Toward the rational design of Cu electrocatalysts for improved performance of the NO3RR | Type | A1 Journal article | ||
Year | 2024 | Publication | ACS applied energy materials | Abbreviated Journal | |
Volume | 7 | Issue | 9 | Pages | 3761-3775 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Cu is one of the most promising materials as an electrocatalyst for the nitrate reduction reaction (NO3RR) to ammonia, a reaction that can simultaneously remove nitrates from wastewater and produce ammonia, a high-value commodity chemical. However, a rational approach to catalyst design is lacking, limiting efficient catalyst optimization. In this work, we propose a way to synthesize monodisperse, polycrystalline Cu NPs with small variances in size by changing the carbon chain length of the phosphonic acid-based ligand. Cu NPs with 8.3, 10.0, and 11.9 nm diameters are successfully synthesized, and high-resolution electron microscopy and tomography are used to characterize these NPs in depth. By isolating Cu NP size as a parameter, we can unequivocally establish its effect on electrochemical performance for the NO3RR to ammonia under optimal operating conditions for the catalyst (0.1 M KOH electrolyte at -1.25 V vs RHE, as established in the first phase). The smallest Cu NPs (8.3 nm with a TDPA ligand) perform best, achieving Faradaic efficiencies (FEs) of 85.4% and absolute current densities of similar to 250 mA cm(-2), with increasing current densities and constant FEs as the particle size decreases. To allow for a rational approach to Cu-based catalyst design from a stability perspective, this work completed a first study of the main degradation pathway that the Cu NPs undergo during NO3RR. High-resolution electron microscopy and tomography are used to characterize the particles at various stages of the reaction. The NPs undergo agglomeration, pulverization, and particle detachment due to the reaction, starting at a particle size of 8.3 nm and progressively getting smaller, but leveling off, until a NP size of 2.6 nm is reached after 2 h of electrolysis. This decrease in NP size goes paired with a decrease in FE from 83% after the first 15 min to 74% after 2 h at -0.75 V vs RHE, despite the increase in active surface area. These insights into the most prominent degradation mechanisms allow for rational adjustments to future catalysts to combat these changes; for example, by embedding NPs in a tailored support, morphological degradation could be impeded. Therefore, these insights allow for a rational approach to the improvement of the stability of Cu-based catalysts for the NO3RR, a very important but often an overlooked aspect of catalyst design. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001228056800001 | Publication Date | 2024-04-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2574-0962 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.4 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 6.4; 2024 IF: NA | |||
Call Number | UA @ admin @ c:irua:206469 | Serial | 9323 | ||
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Author | Peeters, H.; Keulemans, M.; Nuyts, G.; Vanmeert, F.; Li, C.; Minjauw, M.; Detavernier, C.; Bals, S.; Lenaerts, S.; Verbruggen, S.W. | ||||
Title | Plasmonic gold-embedded TiO2 thin films as photocatalytic self-cleaning coatings | Type | A1 Journal article | ||
Year | 2020 | Publication | Applied Catalysis B-Environmental | Abbreviated Journal | Appl Catal B-Environ |
Volume | 267 | Issue | 267 | Pages | 118654 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Transparent photocatalytic TiO2 thin films hold great potential in the development of self-cleaning glass sur- faces, but suffer from a poor visible light response that hinders the application under actual sunlight. To alleviate this problem, the photocatalytic film can be modified with plasmonic nanoparticles that interact very effectively with visible light. Since the plasmonic effect is strongly concentrated in the near surroundings of the nano- particle surface, an approach is presented to embed the plasmonic nanostructures in the TiO2 matrix itself, rather than deposit them loosely on the surface. This way the interaction interface is maximised and the plasmonic effect can be fully exploited. In this study, pre-fabricated gold nanoparticles are made compatible with the organic medium of a TiO2 sol-gel coating suspension, resulting in a one-pot coating suspension. After spin coating, homogeneous, smooth, highly transparent and photoactive gold-embedded anatase thin films are ob- tained. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000518865300002 | Publication Date | 2020-01-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0926-3373 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 22.1 | Times cited | 57 | Open Access | OpenAccess |
Notes | H.P. is grateful to the Research Foundation Flanders (FWO) for an aspirant PhD scholarship. | Approved | Most recent IF: 22.1; 2020 IF: 9.446 | ||
Call Number | EMAT @ emat @c:irua:165616 | Serial | 5446 | ||
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Author | Borah, R.; Ninakanti, R.; Nuyts, G.; Peeters, H.; Pedrazo-Tardajos, A.; Nuti, S.; Vande Velde, C.; De Wael, K.; Lenaerts, S.; Bals, S.; Verbruggen, S. | ||||
Title | Selectivity in ligand functionalization of photocatalytic metal oxide nanoparticles for phase transfer and self‐assembly applications | Type | A1 Journal article | ||
Year | 2021 | Publication | Chemistry-A European Journal | Abbreviated Journal | Chem-Eur J |
Volume | Issue | Pages | chem.202100029-15 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) | ||||
Abstract | Functionalization of photocatalytic metal oxide nanoparticles of TiO 2 , ZnO, WO 3 and CuO with amine‐terminated (oleylamine) and thiol‐terminated (1‐dodecanethiol) alkyl chained ligands was studied under ambient conditions. A high selectivity was observed in the binding specificity of a ligand towards nanoparticles of these different oxides. It was observed that oleylamine binds stably to only TiO 2 and WO 3 , while 1‐dodecanethiol binds stably only to ZnO and CuO. Similarly, polar to non‐polar solvent phase transfer of TiO 2 and WO 3 nanoparticles could be achieved by using oleylamine, but not by 1‐dodecanethiol, while the contrary holds for ZnO and CuO. The surface chemistry of ligand functionalized nanoparticles was probed by ATR‐FTIR spectroscopy, that enabled to elucidate the occupation of the ligands at the active sites. The photo‐stability of the ligands on the nanoparticle surface was determined by the photocatalytic self‐cleaning properties of the material. While TiO 2 and WO 3 degrade the ligands within 24 hours under both UV and visible light, ligands on ZnO and CuO remain unaffected. The gathered insights are also highly relevant from an application point of view. As an example, since the ligand functionalized nanoparticles are hydrophobic in nature, they can thus be self‐assembled at the air‐water interface, for obtaining nanoparticle films with demonstrated photocatalytic as well as anti‐fogging properties. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000652651400001 | Publication Date | 2021-04-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0947-6539 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.317 | Times cited | 15 | Open Access | OpenAccess |
Notes | R.B. and S.W.V. acknowledge financial support from the University of Antwerp Special Research Fund (BOF) for a DOCPRO4 doctoral scholarship. S.B. and A.P.-T. acknowledge financial support from the European Commission under the Horizon 2020 Program by means of the grant agreement no. 731019 EUSMI and the ERC Consolidator grant no. 815128 REALNANO.; sygmaSB | Approved | Most recent IF: 5.317 | ||
Call Number | UA @ admin @ c:irua:177495 | Serial | 6787 | ||
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Author | Bals, S.; Van Aert, S.; Romero, C.P.; Lauwaet, K.; Van Bael, M.J.; Schoeters, B.; Partoens, B.; Yuecelen, E.; Lievens, P.; Van Tendeloo, G. | ||||
Title | Atomic scale dynamics of ultrasmall germanium clusters | Type | A1 Journal article | ||
Year | 2012 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 3 | Issue | 897 | Pages | 897 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Starting from the gas phase, small clusters can be produced and deposited with huge flexibility with regard to composition, materials choice and cluster size. Despite many advances in experimental characterization, a detailed morphology of such clusters is still lacking. Here we present an atomic scale observation as well as the dynamical behaviour of ultrasmall germanium clusters. Using quantitative scanning transmission electron microscopy in combination with ab initio calculations, we are able to characterize the transition between different equilibrium geometries of a germanium cluster consisting of less than 25 atoms. Seven-membered rings, trigonal prisms and some smaller subunits are identified as possible building blocks that stabilize the structure. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000306099900024 | Publication Date | 2012-06-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 90 | Open Access | |
Notes | Fwo; Iap; Iwt | Approved | Most recent IF: 12.124; 2012 IF: 10.015 | ||
Call Number | UA @ lucian @ c:irua:100340 | Serial | 183 | ||
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Author | Zeng, Y.-J.; Schouteden, K.; Amini, M.N.; Ruan, S.-C.; Lu, Y.-F.; Ye, Z.-Z.; Partoens, B.; Lamoen, D.; Van Haesendonck, C. | ||||
Title | Electronic band structures and native point defects of ultrafine ZnO nanocrystals | Type | A1 Journal article | ||
Year | 2015 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 7 | Issue | 7 | Pages | 10617-10622 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Ultrafine ZnO nanocrystals with a thickness down to 0.25 nm are grown by a metalorganic chemical vapor deposition method. Electronic band structures and native point defects of ZnO nanocrystals are studied by a combination of scanning tunneling microscopy/spectroscopy and first-principles density functional theory calculations. Below a critical thickness of nm ZnO adopts a graphitic-like structure and exhibits a wide band gap similar to its wurtzite counterpart. The hexagonal wurtzite structure, with a well-developed band gap evident from scanning tunneling spectroscopy, is established for a thickness starting from similar to 1.4 nm. With further increase of the thickness to 2 nm, V-O-V-Zn defect pairs are easily produced in ZnO nanocrystals due to the self-compensation effect in highly doped semiconductors. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000355055000063 | Publication Date | 2015-04-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244;1944-8252; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 15 | Open Access | |
Notes | Hercules; EWI | Approved | Most recent IF: 7.504; 2015 IF: 6.723 | ||
Call Number | c:irua:126408 | Serial | 999 | ||
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Author | Amini, M.N.; Leenaerts, O.; Partoens, B.; Lamoen, D. | ||||
Title | Graphane- and fluorographene-based quantum dots | Type | A1 Journal article | ||
Year | 2013 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 117 | Issue | 31 | Pages | 16242-16247 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | With the help of first-principles calculations, we investigate graphane/fluorographene heterostructures with special attention for graphane and fluorographene-based quantum dots. Graphane and fluorographene have large electronic band gaps, and we show that their band structures exhibit a strong type-II alignment. In this way, it is possible to obtain confined electron states in fluorographene nanostructures by embedding them in a graphane crystal. Bound hole states can be created in graphane domains embedded in a fluorographene environment. For circular graphane/fluorographene quantum dots, localized states can be observed in the band gap if the size of the radii is larger than approximately 4 to 5 Å. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000323082300046 | Publication Date | 2013-07-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 14 | Open Access | |
Notes | FWO; GOW; Hercules | Approved | Most recent IF: 4.536; 2013 IF: 4.835 | ||
Call Number | UA @ lucian @ c:irua:109457 | Serial | 1367 | ||
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Author | Galván-Moya, J.E.; Altantzis, T.; Nelissen, K.; Peeters, F.M.; Grzelczak, M.; Liz-Marán, L.M.; Bals, S.; Van Tendeloo, G. | ||||
Title | Self-organization of highly symmetric nanoassemblies : a matter of competition | Type | A1 Journal article | ||
Year | 2014 | Publication | ACS nano | Abbreviated Journal | Acs Nano |
Volume | 8 | Issue | 4 | Pages | 3869-3875 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | The properties and applications of metallic nanoparticles are inseparably connected not only to their detailed morphology and composition but also to their structural configuration and mutual interactions. As a result, the assemblies often have superior properties as compared to individual nanoparticles. Although it has been reported that nanoparticles can form highly symmetric clusters, if the configuration can be predicted as a function of the synthesis parameters, more targeted and accurate synthesis will be possible. We present here a theoretical model that accurately predicts the structure and configuration of self-assembled gold nanoclusters. The validity of the model is verified using quantitative experimental data extracted from electron tomography 3D reconstructions of different assemblies. The present theoretical model is generic and can in principle be used for different types of nanoparticles, providing a very wide window of potential applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000334990600084 | Publication Date | 2014-03-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851;1936-086X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 34 | Open Access | OpenAccess |
Notes | FWO; Methusalem; 246791 COUNTATOMS; 335078 COLOURATOM; 262348 ESMI; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 13.942; 2014 IF: 12.881 | ||
Call Number | UA @ lucian @ c:irua:116955 | Serial | 2977 | ||
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Author | Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
Title | Easily doped p-type, low hole effective mass, transparent oxides | Type | A1 Journal article | ||
Year | 2016 | Publication | Scientific reports | Abbreviated Journal | Sci Rep-Uk |
Volume | 6 | Issue | 6 | Pages | 20446 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Fulfillment of the promise of transparent electronics has been hindered until now largely by the lack of semiconductors that can be doped p-type in a stable way, and that at the same time present high hole mobility and are highly transparent in the visible spectrum. Here, a high-throughput study based on first-principles methods reveals four oxides, namely X2SeO2, with X = La, Pr, Nd, and Gd, which are unique in that they exhibit excellent characteristics for transparent electronic device applications – i.e., a direct band gap larger than 3.1 eV, an average hole effective mass below the electron rest mass, and good p-type dopability. Furthermore, for La2SeO2 it is explicitly shown that Na impurities substituting La are shallow acceptors in moderate to strong anion-rich growth conditions, with low formation energy, and that they will not be compensated by anion vacancies VO or VSe. | ||||
Address | EMAT, Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000369568900001 | Publication Date | 2016-02-08 |
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 | 55 | Open Access | |
Notes | We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13 and of a GOA fund from the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government–department EWI. | Approved | Most recent IF: 4.259 | ||
Call Number | c:irua:131611 | Serial | 4036 | ||
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Author | Willhammar, T.; Sentosun, K.; Mourdikoudis, S.; Goris, B.; Kurttepeli, M.; Bercx, M.; Lamoen, D.; Partoens, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Liz-Marzán, L.M.; Bals, S.; Van Tendeloo, G. | ||||
Title | Structure and vacancy distribution in copper telluride nanoparticles influence plasmonic activity in the near-infrared | Type | A1 Journal article | ||
Year | 2017 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 8 | Issue | 8 | Pages | 14925 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Copper chalcogenides find applications in different domains including photonics, photothermal therapy and photovoltaics. CuTe nanocrystals have been proposed as an alternative to noble metal particles for plasmonics. Although it is known that deviations from stoichiometry are a prerequisite for plasmonic activity in the near-infrared, an accurate description of the material and its (optical) properties is hindered by an insufficient understanding of the atomic structure and the influence of defects, especially for materials in their nanocrystalline form. We demonstrate that the structure of Cu1.5±xTe nanocrystals canbe determined using electron diffraction tomography. Real-space high-resolution electron tomography directly reveals the three-dimensional distribution of vacancies in the structure. Through first-principles density functional theory, we furthermore demonstrate that the influence of these vacancies on the optical properties of the nanocrystals is determined. Since our methodology is applicable to a variety of crystalline nanostructured materials, it is expected to provide unique insights concerning structure–property correlations. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000397799700001 | Publication Date | 2017-03-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 37 | Open Access | OpenAccess |
Notes | The work was financially supported by the European Research Council through an ERC Starting Grant (#335078-COLOURATOMS). T.W. acknowledges the Swedish Research Council for an international postdoc grant. We acknowledge financial support of FWO-Vlaanderen through project G.0216.14N, G.0369.15N and a postdoctoral research grant to B.G. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government–Department EWI. The work was further supported by the Spanish MINECO (MAT2013-45168-R). S.M. thanks the Action ooSupporting Postdoctoral Researchers44 of the Operational Program ‘Education and Lifelong Learning’ (Action’s Beneficiary: General Secretariat for Research and Technology of Greece), which was co-financed by the European Social Fund (ESF) and the Greek State. (ROMEO:green; preprint:; postprint:can ; pdfversion:can); ECAS_Sara | Approved | Most recent IF: 12.124 | ||
Call Number | EMAT @ emat @ c:irua:142203UA @ admin @ c:irua:142203 | Serial | 4538 | ||
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Author | Wang, Z.; Wang, Y.B.; Yin, J.; Tovari, E.; Yang, Y.; Lin, L.; Holwill, M.; Birkbeck, J.; Perello, D.J.; Xu, S.; Zultak, J.; Gorbachev, R.V.; Kretinin, A.V.; Taniguchi, T.; Watanabe, K.; Morozov, S.V.; Andelkovic, M.; Milovanović, S.P.; Covaci, L.; Peeters, F.M.; Mishchenko, A.; Geim, A.K.; Novoselov, K.S.; Fal'ko, V.I.; Knothe, A.; Woods, C.R. | ||||
Title | Composite super-moiré lattices in double-aligned graphene heterostructures = Composite super-moire lattices in double-aligned graphene heterostructures | Type | A1 Journal article | ||
Year | 2019 | Publication | Science Advances | Abbreviated Journal | |
Volume | 5 | Issue | 12 | Pages | eaay8897 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | When two-dimensional (2D) atomic crystals are brought into close proximity to form a van der Waals heterostructure, neighbouring crystals may influence each other's properties. Of particular interest is when the two crystals closely match and a moire pattern forms, resulting in modified electronic and excitonic spectra, crystal reconstruction, and more. Thus, moire patterns are a viable tool for controlling the properties of 2D materials. However, the difference in periodicity of the two crystals limits the reconstruction and, thus, is a barrier to the low-energy regime. Here, we present a route to spectrum reconstruction at all energies. By using graphene which is aligned to two hexagonal boron nitride layers, one can make electrons scatter in the differential moire pattern which results in spectral changes at arbitrarily low energies. Further, we demonstrate that the strength of this potential relies crucially on the atomic reconstruction of graphene within the differential moire super cell. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000505069600089 | Publication Date | 2019-12-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2375-2548 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 71 | Open Access | ||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ admin @ c:irua:165754 | Serial | 6289 | ||
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Author | Andelkovic, M.; Milovanović, S.P.; Covaci, L.; Peeters, F.M. | ||||
Title | Double moiré with a twist : supermoiré in encapsulated graphene | Type | A1 Journal article | ||
Year | 2020 | Publication | Nano Letters | Abbreviated Journal | Nano Lett |
Volume | 20 | Issue | 2 | Pages | 979 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | A periodic spatial modulation, as created by a moire pattern, has been extensively studied with the view to engineer and tune the properties of graphene. Graphene encapsulated by hexagonal boron nitride (hBN) when slightly misaligned with the top and bottom hBN layers experiences two interfering moire patterns, resulting in a so-called supermoire (SM). This leads to a lattice and electronic spectrum reconstruction. A geometrical construction of the nonrelaxed SM patterns allows us to indicate qualitatively the induced changes in the electronic properties and to locate the SM features in the density of states and in the conductivity. To emphasize the effect of lattice relaxation, we report band gaps at all Dirac-like points in the hole doped part of the reconstructed spectrum, which are expected to be enhanced when including interaction effects. Our result is able to distinguish effects due to lattice relaxation and due to the interfering SM and provides a clear picture on the origin of recently experimentally observed effects in such trilayer heterostuctures. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000514255400021 | Publication Date | 2020-01-21 | |
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 | 10.8 | Times cited | 48 | Open Access | OpenAccess |
Notes | ; This work was funded by FLAGERA project TRANS2DTMD and the Flemish Science Foundation (FWO-Vl) through a postdoc fellowship for S.P.M. The authors acknowledge useful discussions with W. Zihao and K. Novoselov. ; | Approved | Most recent IF: 10.8; 2020 IF: 12.712 | ||
Call Number | UA @ admin @ c:irua:168685 | Serial | 6490 | ||
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Author | Mao, J.; Milovanović, S.P.; Andelkovic, M.; Lai, X.; Cao, Y.; Watanabe, K.; Taniguchi, T.; Covaci, L.; Peeters, F.M.; Geim, A.K.; Jiang, Y.; Andrei, E.Y. | ||||
Title | Evidence of flat bands and correlated states in buckled graphene superlattices | Type | A1 Journal article | ||
Year | 2020 | Publication | Nature | Abbreviated Journal | Nature |
Volume | 584 | Issue | 7820 | Pages | 215-220 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Two-dimensional atomic crystals can radically change their properties in response to external influences, such as substrate orientation or strain, forming materials with novel electronic structure(1-5). An example is the creation of weakly dispersive, 'flat' bands in bilayer graphene for certain 'magic' angles of twist between the orientations of the two layers(6). The quenched kinetic energy in these flat bands promotes electron-electron interactions and facilitates the emergence of strongly correlated phases, such as superconductivity and correlated insulators. However, the very accurate fine-tuning required to obtain the magic angle in twisted-bilayer graphene poses challenges to fabrication and scalability. Here we present an alternative route to creating flat bands that does not involve fine-tuning. Using scanning tunnelling microscopy and spectroscopy, together with numerical simulations, we demonstrate that graphene monolayers placed on an atomically flat substrate can be forced to undergo a buckling transition(7-9), resulting in a periodically modulated pseudo-magnetic field(10-14), which in turn creates a 'post-graphene' material with flat electronic bands. When we introduce the Fermi level into these flat bands using electrostatic doping, we observe a pseudogap-like depletion in the density of states, which signals the emergence of a correlated state(15-17). This buckling of two-dimensional crystals offers a strategy for creating other superlattice systems and, in particular, for exploring interaction phenomena characteristic of flat bands. Buckled monolayer graphene superlattices are found to provide an alternative to twisted bilayer graphene for the study of flat bands and correlated states in a carbon-based material. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000559831500012 | Publication Date | 2020-08-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0028-0836 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 64.8 | Times cited | 109 | Open Access | Not_Open_Access |
Notes | ; ; | Approved | Most recent IF: 64.8; 2020 IF: 40.137 | ||
Call Number | UA @ admin @ c:irua:171150 | Serial | 6513 | ||
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Author | Joao, S.M.; Andelkovic, M.; Covaci, L.; Rappoport, T.G.; Lopes, J.M.V.P.; Ferreira, A. | ||||
Title | KITE : high-performance accurate modelling of electronic structure and response functions of large molecules, disordered crystals and heterostructures | Type | A1 Journal article | ||
Year | 2020 | Publication | Royal Society Open Science | Abbreviated Journal | Roy Soc Open Sci |
Volume | 7 | Issue | 2 | Pages | 191809-191832 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We present KITE, a general purpose open-source tight-binding software for accurate real-space simulations of electronic structure and quantum transport properties of large-scale molecular and condensed systems with tens of billions of atomic orbitals (N similar to 10(10)). KITE's core is written in C++, with a versatile Python-based interface, and is fully optimized for shared memory multi-node CPU architectures, thus scalable, efficient and fast. At the core of KITE is a seamless spectral expansion of lattice Green's functions, which enables large-scale calculations of generic target functions with uniform convergence and fine control over energy resolution. Several functionalities are demonstrated, ranging from simulations of local density of states and photo-emission spectroscopy of disordered materials to large-scale computations of optical conductivity tensors and real-space wave-packet propagation in the presence of magneto-static fields and spin-orbit coupling. On-the-fly calculations of real-space Green's functions are carried out with an efficient domain decomposition technique, allowing KITE to achieve nearly ideal linear scaling in its multi-threading performance. Crystalline defects and disorder, including vacancies, adsorbates and charged impurity centres, can be easily set up with KITE's intuitive interface, paving the way to user-friendly large-scale quantum simulations of equilibrium and non-equilibrium properties of molecules, disordered crystals and heterostructures subject to a variety of perturbations and external conditions. | ||||
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Language | Wos | 000518020200001 | Publication Date | 2020-02-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2054-5703 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.5 | Times cited | 19 | Open Access | OpenAccess |
Notes | ; T.G.R. and A.F. acknowledge support from the Newton Fund and the Royal Society through the Newton Advanced Fellowship scheme (ref. no. NA150043). M.A. and L.C. acknowledge support from the Trans2DTMD FlagEra project and the VSC (Flemish Supercomputer Center). A.F. acknowledges support from the Royal Society through a University Research Fellowship (ref. nos. UF130385 and URF-R-191021) and an Enhancement Award (ref. no. RGF-EA-180276). T.G.R. acknowledges the support from the Brazilian agencies CNPq and FAPERJ and COMPETE2020, PORTUGAL2020, FEDER and the Portuguese Foundation for Science and Technology (FCT) through project POCI-01-0145-FEDER-028114. S.M.J. is supported by Fundacao para a Ciencia e Tecnologia (FCT) under the grant no. PD/BD/142798/ 2018. S.M.J. and J.M.V.P.L. acknowledge financial support from the FCT, COMPETE 2020 programme in FEDER component (European Union), through projects POCI-01-0145-FEDER028887 and UID/FIS/04650/2013. S.M.J. and J.M.V.P.L. further acknowledge financial support from FCT through national funds, co-financed by COMPETE-FEDER (grant no. M-ERANET2/0002/2016 -UltraGraf) under the Partnership Agreement PT2020. ; | Approved | Most recent IF: 3.5; 2020 IF: 2.243 | ||
Call Number | UA @ admin @ c:irua:167751 | Serial | 6556 | ||
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Author | Achari, A.; Bekaert, J.; Sreepal, V.; Orekhov, A.; Kumaravadivel, P.; Kim, M.; Gauquelin, N.; Pillai, P.B.; Verbeeck, J.; Peeters, F.M.; Geim, A.K.; Milošević, M.V.; Nair, R.R. | ||||
Title | Alternating superconducting and charge density wave monolayers within bulk 6R-TaS₂ | Type | A1 Journal article | ||
Year | 2022 | Publication | Nano letters | Abbreviated Journal | Nano Lett |
Volume | 22 | Issue | 15 | Pages | 6268-6275 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Van der Waals (vdW) heterostructures continue to attract intense interest as a route of designing materials with novel properties that cannot be found in nature. Unfortunately, this approach is currently limited to only a few layers that can be stacked on top of each other. Here, we report a bulk vdW material consisting of superconducting 1H TaS2 monolayers interlayered with 1T TaS2 monolayers displaying charge density waves (CDW). This bulk vdW heterostructure is created by phase transition of 1T-TaS2 to 6R at 800 degrees C in an inert atmosphere. Its superconducting transition (T-c) is found at 2.6 K, exceeding the T-c of the bulk 2H phase. Using first-principles calculations, we argue that the coexistence of superconductivity and CDW within 6R-TaS2 stems from amalgamation of the properties of adjacent 1H and 1T monolayers, where the former dominates the superconducting state and the latter the CDW behavior. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000831832100001 | Publication Date | 2022-07-20 | |
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 | 10.8 | Times cited | 12 | Open Access | OpenAccess |
Notes | This work was supported by the Royal Society, the Leverhulme Trust (PLP-2018-220), the Engineering and Physical Sciences Research Council (EP/N005082/1), and European Research Council (contract 679689). The authors acknowledge the use of the facilities at the Henry Royce Institute and associated support services. J.B. is a postdoctoral fellow of Research Foundation-Flanders (FWO-Vlaanderen). Computational resources were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Governmentdepartment EWI. This work was also performed under a transnational access provision funded by the European Union under the Horizon 2020 programme within a contract for Integrating Activities for Advanced Communities No 823717 − ESTEEM3; esteem3reported; esteem3jra | Approved | Most recent IF: 10.8 | ||
Call Number | UA @ admin @ c:irua:189495 | Serial | 7077 | ||
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Author | Smeyers, R.; Milošević, M.V.; Covaci, L. | ||||
Title | Strong gate-tunability of flat bands in bilayer graphene due to moiré encapsulation between hBN monolayers | Type | A1 Journal article | ||
Year | 2023 | Publication | Nanoscale | Abbreviated Journal | |
Volume | 15 | Issue | 9 | Pages | 4561-4569 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | When using hexagonal boron-nitride (hBN) as a substrate for graphene, the resulting moire pattern creates secondary Dirac points. By encapsulating a multilayer graphene within aligned hBN sheets the controlled moire stacking may offer even richer benefits. Using advanced tight-binding simulations on atomistically-relaxed heterostructures, here we show that the gap at the secondary Dirac point can be opened in selected moire-stacking configurations, and is independent of any additional vertical gating of the heterostructure. On the other hand, gating can broadly tune the gap at the principal Dirac point, and may thereby strongly compress the first moire mini-band in width against the moire-induced gap at the secondary Dirac point. We reveal that in hBN-encapsulated bilayer graphene this novel mechanism can lead to isolated bands flatter than 10 meV under moderate gating, hence presenting a convenient pathway towards electronically-controlled strongly-correlated states on demand. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000933052600001 | Publication Date | 2023-02-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364; 2040-3372 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.7 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 6.7; 2023 IF: 7.367 | |||
Call Number | UA @ admin @ c:irua:195249 | Serial | 7340 | ||
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Author | Paulus, A.; Hendrickx, M.; Mayda, S.; Batuk, M.; Reekmans, G.; von Holst, M.; Elen, K.; Abakumov, A.M.; Adriaensens, P.; Lamoen, D.; Partoens, B.; Hadermann, J.; Van Bael, M.K.; Hardy, A. | ||||
Title | Understanding the Activation of Anionic Redox Chemistry in Ti4+-Substituted Li2MnO3as a Cathode Material for Li-Ion Batteries | Type | A1 Journal article | ||
Year | 2023 | Publication | ACS applied energy materials | Abbreviated Journal | ACS Appl. Energy Mater. |
Volume | 6 | Issue | 13 | Pages | 6956-6971 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Layered Li-rich oxides, demonstrating both cationic and anionic redox chemistry being used as positive electrodes for Li-ion batteries,have raised interest due to their high specific discharge capacities exceeding 250 mAh/g. However, irreversible structural transformations triggered by anionic redox chemistry result in pronounced voltagefade (i.e., lowering the specific energy by a gradual decay of discharge potential) upon extended galvanostatic cycling. Activating or suppressing oxygen anionic redox through structural stabilization induced by redox-inactivecation substitution is a well-known strategy. However, less emphasishas been put on the correlation between substitution degree and theactivation/suppression of the anionic redox. In this work, Ti4+-substituted Li2MnO3 was synthesizedvia a facile solution-gel method. Ti4+ is selected as adopant as it contains no partially filled d-orbitals. Our study revealedthat the layered “honeycomb-ordered” C2/m structure is preserved when increasing the Ticontent to x = 0.2 in the Li2Mn1-x Ti (x) O-3 solidsolution, as shown by electron diffraction and aberration-correctedscanning transmission electron microscopy. Galvanostatic cycling hintsat a delayed oxygen release, due to an improved reversibility of theanionic redox, during the first 10 charge-discharge cyclesfor the x = 0.2 composition compared to the parentmaterial (x = 0), followed by pronounced oxygen redoxactivity afterward. The latter originates from a low activation energybarrier toward O-O dimer formation and Mn migration in Li2Mn0.8Ti0.2O3, as deducedfrom first-principles molecular dynamics (MD) simulations for the“charged” state. Upon lowering the Ti substitution to x = 0.05, the structural stability was drastically improvedbased on our MD analysis, stressing the importance of carefully optimizingthe substitution degree to achieve the best electrochemical performance. | ||||
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Language | Wos | 001018266700001 | Publication Date | 2023-07-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2574-0962 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.4 | Times cited | Open Access | Not_Open_Access: Available from 24.12.2023 | |
Notes | Universiteit Hasselt, AUHL/15/2 – GOH3816N ; Russian Science Foundation, 20-43-01012 ; Fonds Wetenschappelijk Onderzoek, AUHL/15/2 – GOH3816N G040116N ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 6.4; 2023 IF: NA | ||
Call Number | EMAT @ emat @c:irua:198160 | Serial | 8809 | ||
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Author | Conti, S.; Chaves, A.; Pandey, T.; Covaci, L.; Peeters, F.M.; Neilson, D.; Milošević, M.V. | ||||
Title | Flattening conduction and valence bands for interlayer excitons in a moire MoS₂/WSe₂ heterobilayer | Type | A1 Journal article | ||
Year | 2023 | Publication | Nanoscale | Abbreviated Journal | |
Volume | Issue | Pages | 1-11 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We explore the flatness of conduction and valence bands of interlayer excitons in MoS2/WSe2 van der Waals heterobilayers, tuned by interlayer twist angle, pressure, and external electric field. We employ an efficient continuum model where the moire pattern from lattice mismatch and/or twisting is represented by an equivalent mesoscopic periodic potential. We demonstrate that the mismatch moire potential is too weak to produce significant flattening. Moreover, we draw attention to the fact that the quasi-particle effective masses around the Gamma-point and the band flattening are reduced with twisting. As an alternative approach, we show (i) that reducing the interlayer distance by uniform vertical pressure can significantly increase the effective mass of the moire hole, and (ii) that the moire depth and its band flattening effects are strongly enhanced by accessible electric gating fields perpendicular to the heterobilayer, with resulting electron and hole effective masses increased by more than an order of magnitude – leading to record-flat bands. These findings impose boundaries on the commonly generalized benefits of moire twistronics, while also revealing alternative feasible routes to achieve truly flat electron and hole bands to carry us to strongly correlated excitonic phenomena on demand. | ||||
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Language | Wos | 001047512300001 | Publication Date | 2023-07-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364; 2040-3372 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.7 | Times cited | 1 | Open Access | Not_Open_Access: Available from 25.01.2024 |
Notes | Approved | Most recent IF: 6.7; 2023 IF: 7.367 | |||
Call Number | UA @ admin @ c:irua:198290 | Serial | 8819 | ||
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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. |
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Language | Wos | 000417228500017 | Publication Date | 2017-11-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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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 | EMAT @ emat @c:irua:147240UA @ admin @ c:irua:147240 | Serial | 4771 | ||
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