|   | 
Details
   web
Records
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.
Address
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 (down) 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
Permanent link to this record
 

 
Author Herzog, M.J.; Gauquelin, N.; Esken, D.; Verbeeck, J.; Janek, J.
Title Increased Performance Improvement of Lithium-Ion Batteries by Dry Powder Coating of High-Nickel NMC with Nanostructured Fumed Ternary Lithium Metal Oxides Type A1 Journal article
Year 2021 Publication ACS applied energy materials Abbreviated Journal ACS Appl. Energy Mater.
Volume 4 Issue 9 Pages 8832-8848
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Dry powder coating is an effective approach to protect the surfaces of layered cathode active materials (CAMs) in lithium-ion batteries. Previous investigations indicate an incorporation of lithium ions in fumed Al2O3, ZrO2, and TiO2 coatings on LiNi0.7Mn0.15Co0.15O2 during cycling, improving the cycling performance. Here, this coating approach is transferred for the first time to fumed ternary LiAlO2, Li4Zr3O8, and Li4Ti5O12 and directly compared with their lithium-free equivalents. All materials could be processed equally and their nanostructured small aggregates accumulate on the CAM surfaces to quite homogeneous coating layers with a certain porosity. The LiNixMnyCozO2 (NMC) coated with lithium-containing materials shows an enhanced improvement in overall capacity, capacity retention, rate performance, and polarization behavior during cycling, compared to their lithium-free analogues. The highest rate performance was achieved with the fumed ZrO2 coating, while the best long-term cycling stability with the highest absolute capacity was obtained for the fumed LiAlO2-coated NMC. The optimal coating agent for NMC to achieve a balanced system is fumed Li4Ti5O12, providing a good compromise between high rate capability and good capacity retention. The coating agents prevent CAM particle cracking and degradation in the order LiAlO2 ≈ Al2O3 > Li4Ti5O12 > Li4Zr3O8 > ZrO2 > TiO2. A schematic model for the protection and electrochemical performance enhancement of high-nickel NMC with fumed metal oxide coatings is sketched. It becomes apparent that physical and chemical characteristics of the coating significantly influence the performance of NMC. A high degree of coating-layer porosity is favorable for the rate capability, while a high coverage of the surface, especially in vulnerable grain boundaries, enhances the long-term cycling stability and improves the cracking behavior of NMCs. While zirconium-containing coatings possess the best chemical properties for high rate performances, aluminum-containing coatings feature a superior chemical nature to protect high-nickel NMCs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000703338600018 Publication Date 2021-09-27
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 Times cited (down) 15 Open Access OpenAccess
Notes For his support in scanning electron microscopy analysis, the authors thank Erik Peldszus. N. G. and J. V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and from the Flemish Research Fund (FWO) project G0F1320N. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:183949 Serial 6823
Permanent link to this record
 

 
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.
Address
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 (down) 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
Permanent link to this record
 

 
Author Yagmurcukardes, M.; Mogulkoc, Y.; Akgenc, B.; Mogulkoc, A.; Peeters, F.M.
Title Prediction of monoclinic single-layer Janus Ga₂ Te X (X = S and Se) : strong in-plane anisotropy Type A1 Journal article
Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 104 Issue 4 Pages 045425
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By using density functional theory (DFT) based first-principles calculations, electronic, vibrational, piezo-electric, and optical properties of monoclinic Janus single-layer Ga2TeX (X = S or Se) are investigated. The dynamical, mechanical, and thermal stability of the proposed Janus single layers are verified by means of phonon bands, stiffness tensor, and quantum molecular dynamics simulations. The calculated vibrational spectrum reveals the either pure or coupled optical phonon branches arising from Ga-Te and Ga-X atoms. In addition to the in-plane anisotropy, single-layer Janus Ga2TeX exhibits additional out-of-plane asymmetry, which leads to important consequences for its electronic and optical properties. Electronic band dispersions indicate the direct band-gap semiconducting nature of the constructed Janus structures with energy band gaps falling into visible spectrum. Moreover, while orientation-dependent linear-elastic properties of Janus single layers indicate their strong anisotropy, the calculated in-plane stiffness values reveal the ultrasoft nature of the structures. In addition, predicted piezoelectric coefficients show that while there is a strong in-plane anisotropy between piezoelectric constants along armchair (AC) and zigzag (ZZ) directions, there exists a tiny polarization along the out-of-plane direction as a result of the formation of Janus structure. The optical response to electromagnetic radiation has been also analyzed through density functional theory by considering the independent-particle approximation. Finally, the optical spectra of Janus Ga2TeX structures is investigated and it showed a shift from the ultraviolet region to the visible region. The fact that the spectrum is between these regions will allow it to be used in solar energy and many nanoelectronics applications. The predicted monoclinic single-layer Janus Ga2TeX are relevant for promising applications in optoelectronics, optical dichroism, and anisotropic nanoelasticity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000678811100007 Publication Date 2021-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 14 Open Access Not_Open_Access
Notes Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:180404 Serial 7013
Permanent link to this record
 

 
Author Liu, P.; Arslan Irmak, E.; De Backer, A.; De wael, A.; Lobato, I.; Béché, A.; Van Aert, S.; Bals, S.
Title Three-dimensional atomic structure of supported Au nanoparticles at high temperature Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Au nanoparticles (NPs) deposited on CeO2 are extensively used as thermal catalysts since the morphology of the NPs is expected to be stable at elevated temperatures. Although it is well known that the activity of Au NPs depends on their size and surface structure, their three-dimensional (3D) structure at the atomic scale has not been completely characterized as a function of temperature. In this paper, we overcome the limitations of conventional electron tomography by combining atom counting applied to aberration-corrected scanning transmission electron microscopy images and molecular dynamics relaxation. In this manner, we are able to perform an atomic resolution 3D investigation of supported Au NPs. Our results enable us to characterize the 3D equilibrium structure of single NPs as a function of temperature. Moreover, the dynamic 3D structural evolution of the NPs at high temperatures, including surface layer jumping and crystalline transformations, has been studied.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000612999200029 Publication Date 2020-12-29
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 (down) 13 Open Access OpenAccess
Notes This work was supported by the European Research Council (Grant 815128 REALNANO to SB, Grant 770887 PICOMETRICS to SVA, Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through grants to A. D. w. and A. D. B. and project funding G.0267.18N.; sygma; esteem3JRA; esteem3reported Approved Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:174858 Serial 6665
Permanent link to this record
 

 
Author Hamid, I.; Jalali, H.; Peeters, F.M.; Neek-Amal, M.
Title Abnormal in-plane permittivity and ferroelectricity of confined water : from sub-nanometer channels to bulk Type A1 Journal article
Year 2021 Publication Journal Of Chemical Physics Abbreviated Journal J Chem Phys
Volume 154 Issue 11 Pages 114503
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Dielectric properties of nano-confined water are important in several areas of science, i.e., it is relevant in the dielectric double layer that exists in practically all heterogeneous fluid-based systems. Molecular dynamics simulations are used to predict the in-plane dielectric properties of confined water in planar channels of width ranging from sub-nanometer to bulk. Because of suppressed rotational degrees of freedom near the confining walls, the dipole of the water molecules tends to be aligned parallel to the walls, which results in a strongly enhanced in-plane dielectric constant (epsilon (parallel to)) reaching values of about 120 for channels with height 8 angstrom < h < 10 angstrom. With the increase in the width of the channel, we predict that epsilon (parallel to) decreases nonlinearly and reaches the bulk value for h > 70 angstrom. A stratified continuum model is proposed that reproduces the h > 10 angstrom dependence of epsilon (parallel to). For sub-nanometer height channels, abnormal behavior of epsilon (parallel to) is found with two orders of magnitude reduction of epsilon (parallel to) around h similar to 7.5 angstrom, which is attributed to the formation of a particular ice phase that exhibits long-time (similar to mu s) stable ferroelectricity. This is of particular importance for the understanding of the influence of confined water on the functioning of biological systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000629831900001 Publication Date 2021-03-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited (down) 13 Open Access OpenAccess
Notes Approved Most recent IF: 2.965
Call Number UA @ admin @ c:irua:177579 Serial 6967
Permanent link to this record
 

 
Author Albrecht, W.; Van Aert, S.; Bals, S.
Title Three-Dimensional Nanoparticle Transformations Captured by an Electron Microscope Type A1 Journal article
Year 2021 Publication Accounts Of Chemical Research Abbreviated Journal Accounts Chem Res
Volume 54 Issue 5 Pages 1189-1199
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000626269900011 Publication Date 2021-03-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0001-4842 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 20.268 Times cited (down) 12 Open Access OpenAccess
Notes 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 Research Foundation Flanders (FWO, G.0267.18N), and the European Commission (EUSMI). The authors furthermore acknowledge funding from the European Union’s Horizon 2020 research and innovation program, ESTEEM3. The authors also acknowledge contributions from all co-workers that have contributed over the years: Thomas Altantzis, Annick De Backer, Joost Batenburg and co-workers, Armand Béché, Eva Bladt, Lewys Jones and co-workers, Luis Liz-Marzán and co-workers, Ivan Lobato, Thais Milagres de Oliveira, Peter Nellist and co-workers, Hugo Pérez Garza and co-workers, Alexander Skorikov, Sara Skrabalak and co-workers, Sandra Van Aert, Alfons van Blaaderen and co-workers, Hans Vanrompay, Staf Van Tendeloo, and Johan Verbeeck.; sygmaSB; Approved Most recent IF: 20.268
Call Number EMAT @ emat @c:irua:177644 Serial 6752
Permanent link to this record
 

 
Author Arslan Irmak, E.; Liu, P.; Bals, S.; Van Aert, S.
Title 3D Atomic Structure of Supported Metallic Nanoparticles Estimated from 2D ADF STEM Images: A Combination of Atom – Counting and a Local Minima Search Algorithm Type A1 Journal article
Year 2021 Publication Small methods Abbreviated Journal Small Methods
Volume Issue Pages 2101150
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Determining the three-dimensional (3D) atomic structure of nanoparticles (NPs) is critical to understand their structure-dependent properties. It is hereby important to perform such analyses under conditions relevant for the envisioned application. Here, we investigate the 3D structure of supported Au NPs at high temperature, which is of importance to understand their behavior during catalytic reactions. To overcome limitations related to conventional high-resolution electron tomography at high temperature, 3D characterization of NPs with atomic resolution has been performed by applying atom-counting using atomic resolution annular darkfield scanning transmission electron microscopy (ADF STEM) images followed by structural relaxation. However, at high temperatures, thermal displacements, which affect the ADF STEM intensities, should be taken into account. Moreover, it is very likely that the structure of a NP investigated at elevated temperature deviates from a ground state configuration, which is difficult to determine using purely computational energy minimization approaches. In this paper, we therefore propose an optimized approach using an iterative local minima search algorithm followed by molecular dynamics (MD) structural relaxation of candidate structures associated with each local minimum. In this manner, it becomes possible to investigate the 3D atomic structure of supported NPs, which may deviate from their ground state configuration.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000716511600001 Publication Date 2021-11-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2366-9608 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 12 Open Access OpenAccess
Notes This work was supported by the European Research Council (Grant 815128 REALNANO to SB, Grant 770887 PICOMETRICS to SVA, Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0267.18N, G.0502.18N, G.0346.21N).; sygmaSB; esteem3jra; esteem3reported Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:183289 Serial 6820
Permanent link to this record
 

 
Author Pandey, T.; Covaci, L.; Milošević, M.V.; Peeters, F.M.
Title Flexoelectricity and transport properties of phosphorene nanoribbons under mechanical bending Type A1 Journal article
Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 103 Issue 23 Pages 235406
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We examine from first principles the flexoelectric properties of phosphorene nanoribbons under mechanical bending along armchair and zigzag directions. In both cases we find that the radial polarization depends linearly on the strain gradient. The flexoelectricity along the armchair direction is over 40% larger than along the zigzag direction. The obtained flexoelectric coefficients of phosphorene are four orders of magnitude larger than those of graphene and comparable to transition metal dichalcogenides. Analysis of charge density shows that the flexoelectricity mainly arises from the pz orbitals of phosphorus atoms. The electron mobilities in bent phosphorene can be enhanced by over 60% along the armchair direction, which is significantly higher than previous reports of mobility tuned by uniaxial strain. Our results indicate phosphorene is a candidate for a two-dimensional material applicable in flexible-electronic devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000657129800006 Publication Date 2021-06-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 12 Open Access Not_Open_Access
Notes Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:179109 Serial 6996
Permanent link to this record
 

 
Author Skorikov, A.; Heyvaert, W.; Albecht, W.; Pelt, D.M.; Bals, S.
Title Deep learning-based denoising for improved dose efficiency in EDX tomography of nanoparticles Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue Pages 12242-12249
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The combination of energy-dispersive X-ray spectroscopy (EDX) and electron tomography is a powerful approach to retrieve the 3D elemental distribution in nanomaterials, providing an unprecedented level of information for complex, multi-component systems, such as semiconductor devices, as well as catalytic and plasmonic nanoparticles. Unfortunately, the applicability of EDX tomography is severely limited because of extremely long acquisition times and high electron irradiation doses required to obtain 3D EDX reconstructions with an adequate signal-to-noise ratio. One possibility to address this limitation is intelligent denoising of experimental data using prior expectations about the objects of interest. Herein, this approach is followed using the deep learning methodology, which currently demonstrates state-of-the-art performance for an increasing number of data processing problems. Design choices for the denoising approach and training data are discussed with a focus on nanoparticle-like objects and extremely noisy signals typical for EDX experiments. Quantitative analysis of the proposed method demonstrates its significantly enhanced performance in comparison to classical denoising approaches. This allows for improving the tradeoff between the reconstruction quality, acquisition time and radiation dose for EDX tomography. The proposed method is therefore especially beneficial for the 3D EDX investigation of electron beam-sensitive materials and studies of nanoparticle transformations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000671395800001 Publication Date 2021-07-08
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 (down) 11 Open Access OpenAccess
Notes Nederlandse Organisatie voor Wetenschappelijk Onderzoek, 016.Veni.192.235 ; H2020 European Research Council, 815128 ; H2020 Marie Skłodowska-Curie Actions, 797153 ; H2020 Research Infrastructures, 731019; realnano; sygmaSB Approved Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:179756 Serial 6799
Permanent link to this record
 

 
Author Walters, A.A.; Santacana-Font, G.; Li, J.; Routabi, N.; Qin, Y.; Claes, N.; Bals, S.; Tzu-Wen Wang, J.; Al-Jamal, K.T.
Title Nanoparticle-MediatedIn SituMolecular Reprogramming of Immune Checkpoint Interactions for Cancer Immunotherapy Type A1 Journal article
Year 2021 Publication Acs Nano Abbreviated Journal Acs Nano
Volume 15 Issue 11 Pages 17549-17564
Keywords A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Immune checkpoint blockade involves targeting immune

regulatory molecules with antibodies. Preclinically, complex multiantibody

regimes of both inhibitory and stimulatory targets are a promising

candidate for the next generation of immunotherapy. However, in this

setting, the antibody platform may be limited due to excessive toxicity

caused by off target effects as a result of systemic administration. RNA

can be used as an alternate to antibodies as it can both downregulate

immunosuppressive checkpoints (siRNA) or induce expression of

immunostimulatory checkpoints (mRNA). In this study, we demonstrate

that the combination of both siRNA and mRNA in a single

formulation can simultaneously knockdown and induce expression of

immune checkpoint targets, thereby reprogramming the tumor

microenvironment from immunosuppressive to immunostimulatory

phenotype. To achieve this, RNA constructs were synthesized and

formulated into stable nucleic acid lipid nanoparticles (SNALPs); the SNALPs produced were 140−150 nm in size with >80%

loading efficiency. SNALPs could transfect macrophages and B16F10 cells in vitro resulting in 75% knockdown of inhibitory

checkpoint (PDL1) expression and simultaneously express high levels of stimulatory checkpoint (OX40L) with minimal

toxicity. Intratumoral treatment with the proposed formulation resulted in statistically reduced tumor growth, a greater

density of CD4+ and CD8+ infiltrates in the tumor, and immune activation within tumor-draining lymph nodes. These data

suggest that a single RNA-based formulation can successfully reprogram multiple immune checkpoint interactions on a

cellular level. Such a candidate may be able to replace future immune checkpoint therapeutic regimes composed of both

stimulatory- and inhibitory-receptor-targeting antibodies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000747115200039 Publication Date 2021-11-23
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 (down) 11 Open Access OpenAccess
Notes A.A.W. is the grateful recipient of a Maplethorpe Fellowship. K.A.J. acknowledges funding from the British Council (Newton Fund, 337313), Wellcome Trust (WT103913), and the Cancer Research UK King’s Health Partners Centre at King’s College London. Financial support is acknowledged from the European Commission under the Horizon 2020 Programme, by means of Grant Agreement No. 731019 (EUSMI). Images were drawn on BioRender.com. Approved Most recent IF: 13.942
Call Number EMAT @ emat @c:irua:183950 Serial 6829
Permanent link to this record
 

 
Author Dehdast, M.; Valiollahi, Z.; Neek-Amal, M.; Van Duppen, B.; Peeters, F.M.; Pourfath, M.
Title Tunable natural terahertz and mid-infrared hyperbolic plasmons in carbon phosphide Type A1 Journal article
Year 2021 Publication Carbon Abbreviated Journal Carbon
Volume 178 Issue Pages 625-631
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Hyperbolic polaritons in ultra thin materials such as few layers of van derWaals heterostructures provide a unique control over light-matter interaction at the nanoscale and with various applications in flat optics. Natural hyperbolic surface plasmons have been observed on thin films of WTe2 in the light wavelength range of 16-23 mu m (similar or equal to 13-18 THz) [Nat. Commun. 11, 1158 (2020)]. Using time-dependent density functional theory, it is found that carbon doped monolayer phosphorene (beta-allotrope of carbon phosphide monolayer) exhibits natural hyperbolic plasmons at frequencies above similar or equal to 5 THz which is not observed in its parent materials, i.e. monolayer of black phosphorous and graphene. Furthermore, we found that by electrostatic doping the plasmonic frequency range can be extended to the mid-infrared. (C) 2021 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000648729800057 Publication Date 2021-03-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited (down) 11 Open Access Not_Open_Access
Notes Approved Most recent IF: 6.337
Call Number UA @ admin @ c:irua:179033 Serial 7039
Permanent link to this record
 

 
Author Li, C.; Tardajos, A.P.; Wang, D.; Choukroun, D.; Van Daele, K.; Breugelmans, T.; Bals, S.
Title A simple method to clean ligand contamination on TEM grids Type A1 Journal article
Year 2021 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 221 Issue Pages 113195
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Colloidal nanoparticles (NPs) including nanowires and nanosheets made by chemical methods involve many organic ligands. When the structure of NPs is investigated via transmission electron microscopy (TEM), the organic ligands act as a source for e-beam induced deposition and this causes substantial build-up of carbon layers in the investigated areas, which is typically referred to as “contamination” in the eld of electron mi- croscopy. This contamination is often more severe for scanning TEM, a technique that is based on a focused electron beam and hence higher electron dose rate. In this paper, we report a simple and effective method to clean drop-cast TEM grids that contain NPs with ligands. Using a combination of activated carbon and ethanol, this method effectively reduces the amount of ligands on TEM grids, and therefore greatly improves the quality of electron microscopy images and subsequent analytical measurements. This ef cient and facile method can be helpful during electron microscopy investigation of different kinds of nanomaterials that suffer from ligand- induced contamination.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000612539600002 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited (down) 10 Open Access OpenAccess
Notes This research was funded by the University Antwerp GOA project (ID 33928). DW acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 894254 SuprAtom). Approved Most recent IF: 2.843
Call Number EMAT @ emat @c:irua:174947 Serial 6666
Permanent link to this record
 

 
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.
Address
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 (down) 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 EMAT @ emat @c:irua:175872 Serial 6673
Permanent link to this record
 

 
Author Wang, J.; Van Pottelberge, R.; Jacobs, A.; Van Duppen, B.; Peeters, F.M.
Title Confinement and edge effects on atomic collapse in graphene nanoribbons Type A1 Journal article
Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 103 Issue 3 Pages 035426
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Atomic collapse in graphene nanoribbons behaves in a fundamentally different way as compared to monolayer graphene due to the presence of multiple energy bands and the effect of edges. For armchair nanoribbons we find that bound states gradually transform into atomic collapse states with increasing impurity charge. This is very different in zigzag nanoribbons where multiple quasi-one-dimensional bound states are found that originates from the zero-energy zigzag edge states. They are a consequence of the flat band and the electron distribution of these bound states exhibits two peaks. The lowest-energy edge state transforms from a bound state into an atomic collapse resonance and shows a distinct relocalization from the edge to the impurity position with increasing impurity charge.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000610779200008 Publication Date 2021-01-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 10 Open Access OpenAccess
Notes Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:176585 Serial 6719
Permanent link to this record
 

 
Author Xia, C.; Pedrazo-Tardajos, A.; Wang, D.; Meeldijk, J.D.; Gerritsen, H.C.; Bals, S.; de Donega, C.M.
Title Seeded growth combined with cation exchange for the synthesis of anisotropic Cu2-xS/ZnS, Cu2-xS, and CuInS2 nanorods Type A1 Journal article
Year 2021 Publication Chemistry of materials Abbreviated Journal
Volume 33 Issue 1 Pages 102-116
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Colloidal copper(I) sulfide (Cu2-xS) nanocrystals (NCs) have attracted much attention for a wide range of applications because of their unique optoelectronic properties, driving scientists to explore the potential of using Cu2-xS NCs as seeds in the synthesis of heteronanocrystals to achieve new multifunctional materials. Herein, we developed a multistep synthesis strategy toward Cu2-xS/ZnS heteronanorods. The Janus-type Cu2-xS/ZnS heteronanorods are obtained by the injection of hexagonal high-chalcocite Cu2-xS seed NCs in a hot zinc oleate solution in the presence of suitable surfactants, 20 s after the injection of sulfur precursors. The Cu2-xS seed NCs undergo rapid aggregation and coalescence in the first few seconds after the injection, forming larger NCs that act as the effective seeds for heteronucleation and growth of ZnS. The ZnS heteronucleation occurs on a single (100) facet of the Cu2-xS seed NCs and is followed by fast anisotropic growth along a direction that is perpendicular to the c-axis, thus leading to Cu2-xS/ZnS Janus-type heteronanorods with a sharp heterointerface. Interestingly, the high-chalcocite crystal structure of the injected Cu2-xS seed NCs is preserved in the Cu2-xS segments of the heteronanorods because of the highthermodynamic stability of this Cu2-xS phase. The Cu2-xS/ZnS heteronanorods are subsequently converted into single-component Cu2-xS and CuInS2 nanorods by postsynthetic topotactic cation exchange. This work expands the possibilities for the rational synthesis of colloidal multicomponent heteronanorods by allowing the design principles of postsynthetic heteroepitaxial seeded growth and nanoscale cation exchange to be combined, yielding access to a plethora of multicomponent heteronanorods with diameters in the quantum confinement regime.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000610984700009 Publication Date 2020-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 10 Open Access OpenAccess
Notes C.X. acknowledges China Scholarship Council (CSC) for the financial support (grant number 201406330055). C.d.M.D. acknowledges funding from the European Commission for access to the EMAT facilities (grant number EUSMI E180900184). D.W. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 894254 SuprAtom). S.B. acknowledges support by means of the ERC Consolidator grant no. 815128 REALNANO. The authors thank Donglong Fu for XRD measurements.; sygma Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:176587 Serial 6732
Permanent link to this record
 

 
Author González‐Rubio, G.; Díaz‐Núñez, P.; Albrecht, W.; Manzaneda‐González, V.; Bañares, L.; Rivera, A.; Liz‐Marzán, L.M.; Peña‐Rodríguez, O.; Bals, S.; Guerrero‐Martínez, A.
Title Controlled Alloying of Au@Ag Core–Shell Nanorods Induced by Femtosecond Laser Irradiation Type A1 Journal article
Year 2021 Publication Advanced Optical Materials Abbreviated Journal Adv Opt Mater
Volume Issue Pages 2002134
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000625964300001 Publication Date 2021-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2195-1071 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.875 Times cited (down) 10 Open Access OpenAccess
Notes G.G.‐R., P.D.‐N., and W.A. contributed equally to this work. This work was funded by the Spanish Ministry of Science, Innovation and Universities (MICIU) (Grant Nos. RTI2018‐095844‐B‐I00, PID2019‐105325RB, and PGC2018‐096444‐B‐I00), the Madrid Regional Government (Grant Nos. P2018/NMT‐4389 and S2018/EMT‐4437), and the EUROfusion Consortium (grant ENR‐IFE19.CCFE‐01). This work was supported by COST (European Cooperation in Science and Technology) Action TUMIEE (Grant No. CA17126). S.B. and W.A. acknowledge funding from the European Research Council under the European Union's Horizon 2020 Research and Innovation Program (ERC Consolidator Grant No. 815128 – REALNANO). All the authors acknowledge funding from the European Commission (Grant No. E180900184‐EUSMI). G.G.‐R. thanks the Spanish MICIU for an FPI (Grant No. BES‐2014‐068972) fellowship. W.A. acknowledges an Individual Fellowship from the Marie Sklodowska‐Curie actions (MSCA) under the EU's Horizon 2020 Program (Grant No. 797153, SOPMEN). The facilities provided by the Center for Ultrafast Laser of Complutense University of Madrid are gratefully acknowledged. The authors also acknowledge the computer resources and technical assistance provided by CESVIMA (UPM).; sygmaSB Approved Most recent IF: 6.875
Call Number EMAT @ emat @c:irua:177586 Serial 6758
Permanent link to this record
 

 
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.
Address
Corporate Author Thesis
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 (down) 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
Permanent link to this record
 

 
Author Jannis, D.; Müller-Caspary, K.; Béché, A.; Verbeeck, J.
Title Coincidence Detection of EELS and EDX Spectral Events in the Electron Microscope Type A1 Journal article
Year 2021 Publication Applied Sciences-Basel Abbreviated Journal Appl Sci-Basel
Volume 11 Issue 19 Pages 9058
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Recent advances in the development of electron and X-ray detectors have opened up the possibility to detect single events from which its time of arrival can be determined with nanosecond resolution. This allows observing time correlations between electrons and X-rays in the transmission electron microscope. In this work, a novel setup is described which measures individual events using a silicon drift detector and digital pulse processor for the X-rays and a Timepix3 detector for the electrons. This setup enables recording time correlation between both event streams while at the same time preserving the complete conventional electron energy loss (EELS) and energy dispersive X-ray (EDX) signal. We show that the added coincidence information improves the sensitivity for detecting trace elements in a matrix as compared to conventional EELS and EDX. Furthermore, the method allows the determination of the collection efficiencies without the use of a reference sample and can subtract the background signal for EELS and EDX without any prior knowledge of the background shape and without pre-edge fitting region. We discuss limitations in time resolution arising due to specificities of the silicon drift detector and discuss ways to further improve this aspect.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000710160300001 Publication Date 2021-09-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2076-3417 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.679 Times cited (down) 9 Open Access OpenAccess
Notes Fonds Wetenschappelijk Onderzoek, G042920 ; Horizon 2020 Framework Programme, 101017720 ; Helmholtz-Fonds, VH-NG-1317 ; Approved Most recent IF: 1.679
Call Number EMAT @ emat @c:irua:183336 Serial 6821
Permanent link to this record
 

 
Author Renero-Lecuna, C.; Herrero, A.; Jimenez de Aberasturi, D.; Martínez-Flórez, M.; Valiente, R.; Mychinko, M.; Bals, S.; Liz-Marzán, L.M.
Title Nd3+-Doped Lanthanum Oxychloride Nanocrystals as Nanothermometers Type A1 Journal article
Year 2021 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume 125 Issue 36 Pages 19887-19896
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The development of optical nanothermometers operating in the near-infrared (NIR) is of high relevance toward temperature measurements in biological systems. We propose herein the use of Nd3+-doped lanthanum oxychloride nanocrystals as an efficient system with intense photoluminescence under NIR irradiation in the first biological transparency window and emission in the second biological window with excellent emission stability over time under 808 nm excitation, regardless of Nd3+ concentration, which can be considered as a particular strength of our system. Additionally, surface passivation through overgrowth of an inert LaOCl shell around optically active LaOCl/Nd3+ cores was found to further enhance the photoluminescence intensity and also the lifetime of the 1066 nm, 4F3/2 to 4I11/2 transition, without affecting its (ratiometric) sensitivity toward temperature changes. As required for biological applications, we show that the obtained (initially hydrophobic) nanocrystals can be readily transferred into aqueous solvents with high, long-term stability, through either ligand exchange or encapsulation with an amphiphilic polymer.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000697335100031 Publication Date 2021-09-16
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 (down) 9 Open Access OpenAccess
Notes The authors thank the financial support of the European Research Council (ERC-AdG-2017 787510, ERC-CoG-2019 815128) and of the European Commission (EUSMI, Grant 731019). This work was performed under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency−Grant MDM-2017−0720. Realnano; sygmaSB Approved Most recent IF: 4.536
Call Number EMAT @ emat @c:irua:181671 Serial 6831
Permanent link to this record
 

 
Author Cunha, S.M.; de Costa, D.R.; Pereira Jr, J.M.; Costa Filho, R.N.; Van Duppen, B.; Peeters, F.M.
Title Band-gap formation and morphing in alpha-T-3 superlattices Type A1 Journal article
Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 104 Issue 11 Pages 115409
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Electrons in alpha-T-3 lattices behave as condensed-matter analogies of integer-spin Dirac fermions. The three atoms making up the unit cell bestow the energy spectrum with an additional energy band that is completely flat, providing unique electronic properties. The interatomic hopping term, alpha, is known to strongly affect the electronic spectrum of the two-dimensional (2D) lattice, allowing it to continuously morph from graphenelike responses to the behavior of fermions in a dice lattice. For pristine lattice structures the energy bands are gapless, but small deviations in the atomic equivalence of the three sublattices will introduce gaps in the spectrum. It is unknown how these affect transport and electronic properties such as the energy spectrum of superlattice minibands. Here we investigate the dependency of these properties on the parameter a accounting for different symmetry-breaking terms, and we show how it affects band-gap formation. Furthermore, we find that superlattices can force band gaps to close and shift in energy. Our results demonstrate that alpha-T-3 superlattices provide a versatile material for 2D band-gap engineering purposes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000696091600003 Publication Date 2021-09-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 9 Open Access OpenAccess
Notes Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:181544 Serial 6972
Permanent link to this record
 

 
Author Akbali, B.; Yagmurcukardes, M.; Peeters, F.M.; Lin, H.-Y.; Lin, T.-Y.; Chen, W.-H.; Maher, S.; Chen, T.-Y.; Huang, C.-H.
Title Determining the molecular orientation on the metal nanoparticle surface through surface-enhanced Raman spectroscopy and density functional theory simulations Type A1 Journal article
Year 2021 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume 125 Issue 29 Pages 16289-16295
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We report here the efficacy of surface-enhanced Raman spectroscopy (SERS) measurements as a probe for molecular orientation. 4-Aminobenzoic acid (PABA) on a surface consisting of silver (Ag) nanoparticles (NPs) is investigated. We find that the orientation of the PABA molecule on the SERS substrate is estimated based on the relative change in the magnitude of the C-H stretching bands on the SERS substrate, and it is found that the molecule assumes a horizontal orientation on the Ag-NP surface. The strong molecule-metal interaction is determined by an abnormal enhanced SERS band appearing at 980 cm(-1), and the peak is assigned to an out-of-plane amine vibrational mode, which is supported by our ab initio calculations. DFT-based Raman activity calculations corroborate the SERS results, revealing that (i) the PABA molecule attaches to the surface of Ag-NPs with its alpha dimers rather than single-molecule binding and (ii) the molecule preserves its alpha dimers in an aqueous environment. Our results demonstrate that SERS can be used to gain deeper insights into the molecular orientation on metal nanoparticle surfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000680445800055 Publication Date 2021-07-19
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 (down) 9 Open Access Not_Open_Access
Notes Approved Most recent IF: 4.536
Call Number UA @ admin @ c:irua:180455 Serial 6978
Permanent link to this record
 

 
Author Conti, S.; Saberi-Pouya, S.; Perali, A.; Virgilio, M.; Peeters, F.M.; Hamilton, A.R.; Scappucci, G.; Neilson, D.
Title Electron-hole superfluidity in strained Si/Ge type II heterojunctions Type A1 Journal article
Year 2021 Publication npj Quantum Materials Abbreviated Journal
Volume 6 Issue 1 Pages 41
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Excitons are promising candidates for generating superfluidity and Bose-Einstein condensation (BEC) in solid-state devices, but an enabling material platform with in-built band structure advantages and scaling compatibility with industrial semiconductor technology is lacking. Here we predict that spatially indirect excitons in a lattice-matched strained Si/Ge bilayer embedded into a germanium-rich SiGe crystal would lead to observable mass-imbalanced electron-hole superfluidity and BEC. Holes would be confined in a compressively strained Ge quantum well and electrons in a lattice-matched tensile strained Si quantum well. We envision a device architecture that does not require an insulating barrier at the Si/Ge interface, since this interface offers a type II band alignment. Thus the electrons and holes can be kept very close but strictly separate, strengthening the electron-hole pairing attraction while preventing fast electron-hole recombination. The band alignment also allows a one-step procedure for making independent contacts to the electron and hole layers, overcoming a significant obstacle to device fabrication. We predict superfluidity at experimentally accessible temperatures of a few Kelvin and carrier densities up to similar to 6 x 10(10) cm(-2), while the large imbalance of the electron and hole effective masses can lead to exotic superfluid phases.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000642904200001 Publication Date 2021-04-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-4648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 9 Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:178226 Serial 6984
Permanent link to this record
 

 
Author Mychinko, M.; Skorikov, A.; Albrecht, W.; Sánchez‐Iglesias, A.; Zhuo, X.; Kumar, V.; Liz‐Marzán, L.M.; Bals, S.
Title The Influence of Size, Shape, and Twin Boundaries on Heat‐Induced Alloying in Individual Au@Ag Core–Shell Nanoparticles Type A1 Journal article
Year 2021 Publication Small Abbreviated Journal Small
Volume Issue Pages 2102348
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Environmental conditions during real-world application of bimetallic core–shell nanoparticles (NPs) often include the use of elevated temperatures, which are known to cause elemental redistribution, in turn significantly altering the properties of these nanomaterials. Therefore, a thorough understanding of such processes is of great importance. The recently developed combination of fast electron tomography with in situ heating holders is a powerful approach to investigate heat-induced processes at the single NP level, with high spatial resolution in 3D. In combination with 3D finite-difference diffusion simulations, this method can be used to disclose the influence of various NP parameters on the diffusion dynamics in Au@Ag core–shell systems. A detailed study of the influence of heating on atomic diffusion and alloying for Au@Ag NPs with varying core morphology and crystallographic details is carried out. Whereas the core shape and aspect ratio of the NPs play a minor role, twin boundaries are found to have a strong influence on the elemental diffusion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000673326600001 Publication Date 2021-07-14
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 (down) 8 Open Access OpenAccess
Notes The funding for this project was provided by European Research Council (ERC Consolidator Grant 815128, REALNANO) and European Commission (grant 731019, EUSMI and grant 26019, ESTEEM). This work was performed under the Maria de Maeztu Units of Excellence Programme-Grant No. MDM-2017-0720, Ministry of Science and Innovation.; sygmaSB Approved Most recent IF: 8.643
Call Number EMAT @ emat @c:irua:179856 Serial 6804
Permanent link to this record
 

 
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 (down) 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
Permanent link to this record
 

 
Author Petrov, M.; Bekaert, J.; Milošević, M.V.
Title Superconductivity in gallenene Type A1 Journal article
Year 2021 Publication 2d Materials Abbreviated Journal 2D Mater
Volume 8 Issue 3 Pages 035056
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Among the large variety of two-dimensional (2D) materials discovered to date, elemental monolayers that host superconductivity are very rare. Using ab initio calculations we show that recently synthesized gallium monolayers, coined gallenene, are intrinsically superconducting through electron-phonon coupling. We reveal that Ga-100 gallenene, a planar monolayer isostructural with graphene, is the structurally simplest 2D superconductor to date, furthermore hosting topological edge states due to its honeycomb structure. Our anisotropic Eliashberg calculations show distinctly three-gap superconductivity in Ga-100, in contrast to the alternative buckled Ga-010 gallenene which presents a single anisotropic superconducting gap. Strikingly, the critical temperature (T ( c )) of gallenene is in the range of 7-10 K, exceeding the T ( c ) of bulk gallium from which it is exfoliated. Finally we explore chemical functionalization of gallenene with hydrogen, and report induced multigap superconductivity with an enhanced T ( c ) in the resulting gallenane compound.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000667458500001 Publication Date 2021-06-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.937 Times cited (down) 8 Open Access OpenAccess
Notes Approved Most recent IF: 6.937
Call Number UA @ admin @ c:irua:179623 Serial 7025
Permanent link to this record
 

 
Author Ceyhan, E.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H.
Title Electronic and magnetic properties of single-layer FeCl₂ with defects Type A1 Journal article
Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 103 Issue 1 Pages 014106
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The formation of lattice defects and their effect on the electronic properties of single-layer FeCl2 are investigated by means of first-principles calculations. Among the vacancy defects, namely mono-, di-, and three-Cl vacancies and mono-Fe vacancy, the formation of mono-Cl vacancy is the most preferable. Comparison of two different antisite defects reveals that the formation of the Fe-antisite defect is energetically preferable to the Cl-antisite defect. While a single Cl vacancy leads to a 1 mu(B) decrease in the total magnetic moment of the host lattice, each Fe vacant site reduces the magnetic moment by 4 mu(B). However, adsorption of an excess Cl atom on the surface changes the electronic structure to a ferromagnetic metal or to a ferromagnetic semiconductor depending on the adsorption site without changing the ferromagnetic state of the host lattice. Both Cl-antisite and Fe-antisite defected domains change the magnetic moment of the host lattice by -1 mu(B) and +3 mu(B), respectively. The electronic ground state of defected structures reveals that (i) single-layer FeCl2 exhibits half-metallicity under the formation of vacancy and Cl-antisite defects; (ii) ferromagnetic metallicity is obtained when a single Cl atom is adsorbed on upper-Cl and Fe sites, respectively; and (iii) ferromagnetic semiconducting behavior is found when a Cl atom is adsorbed on a lower-Cl site or a Fe-antisite defect is formed. Simulated scanning electron microscope images show that atomic-scale identification of defect types is possible from their electronic charge density. Further investigation of the periodically Fe-defected structures reveals that the formation of the single-layer FeCl3 phase, which is a dynamically stable antiferromagnetic semiconductor, is possible. Our comprehensive analysis on defects in single-layer FeCl2 will complement forthcoming experimental observations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000606969400002 Publication Date 2021-01-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 7 Open Access Not_Open_Access
Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and by Flemish Supercomputer Center (VSC). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. M.Y. was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:176039 Serial 6689
Permanent link to this record
 

 
Author Jalali, H.; Khoeini, F.; Peeters, F.M.; Neek-Amal, M.
Title Hydration effects and negative dielectric constant of nano-confined water between cation intercalated MXenes Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue 2 Pages 922-929
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Using electrochemical methods a profound enhancement of the capacitance of electric double layer capacitor electrodes was reported when water molecules are strongly confined into the two-dimensional slits of titanium carbide MXene nanosheets [A. Sugahara et al., Nat. Commun., 2019, 10, 850]. We study the effects of hydration on the dielectric properties of nanoconfined water and supercapacitance properties of the cation intercalated MXene. A model for the electric double layer capacitor is constructed where water molecules are strongly confined in two-dimensional slits of MXene. We report an abnormal dielectric constant and polarization of nano-confined water between MXene layers. We found that by decreasing the ionic radius of the intercalated cations and in a critical hydration shell radius the capacitance of the system increases significantly (similar or equal to 200 F g(-1)) which can be interpreted as a negative permittivity. This study builds a bridge between the fundamental understanding of the dielectric properties of nanoconfined water and the capability of using MXene films for supercapacitor technology, and in doing so provides a solid theoretical support for recent experiments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000610368100035 Publication Date 2020-12-08
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 (down) 7 Open Access Not_Open_Access
Notes ; ; Approved Most recent IF: 7.367
Call Number UA @ admin @ c:irua:176141 Serial 6690
Permanent link to this record
 

 
Author Dingenen, F.; Blommaerts, N.; Van Hal, M.; Borah, R.; Arenas-Esteban, D.; Lenaerts, S.; Bals, S.; Verbruggen, S.W.
Title Layer-by-Layer-Stabilized Plasmonic Gold-Silver Nanoparticles on TiO2: Towards Stable Solar Active Photocatalysts Type A1 Journal article
Year 2021 Publication Nanomaterials Abbreviated Journal Nanomaterials-Basel
Volume 11 Issue 10 Pages 2624
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract To broaden the activity window of TiO2, a broadband plasmonic photocatalyst has been designed and optimized. This plasmonic ‘rainbow’ photocatalyst consists of TiO2 modified with gold–silver composite nanoparticles of various sizes and compositions, thus inducing a broadband interaction with polychromatic solar light. However, these nanoparticles are inherently unstable, especially due to the use of silver. Hence, in this study the application of the layer-by-layer technique is introduced to create a protective polymer shell around the metal cores with a very high degree of control. Various TiO2 species (pure anatase, PC500, and P25) were loaded with different plasmonic metal loadings (0–2 wt %) in order to identify the most solar active composite materials. The prepared plasmonic photocatalysts were tested towards stearic acid degradation under simulated sunlight. From all materials tested, P25 + 2 wt % of plasmonic ‘rainbow’ nanoparticles proved to be the most promising (56% more efficient compared to pristine P25) and was also identified as the most cost-effective. Further, 2 wt % of layer-by-layer-stabilized ‘rainbow’ nanoparticles were loaded on P25. These layer-by-layer-stabilized metals showed superior stability under a heated oxidative atmosphere, as well as in a salt solution. Finally, the activity of the composite was almost completely retained after 1 month of aging, while the nonstabilized equivalent lost 34% of its initial activity. This work shows for the first time the synergetic application of a plasmonic ‘rainbow’ concept and the layer-by-layer stabilization technique, resulting in a promising solar active, and long-term stable photocatalyst.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000712759800001 Publication Date 2021-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2079-4991 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.553 Times cited (down) 7 Open Access OpenAccess
Notes Research was funded by Research Foundation—Flanders (FWO), FN 700300001— Aspirant F. Dingenen. Approved Most recent IF: 3.553
Call Number EMAT @ emat @c:irua:183281 Serial 6812
Permanent link to this record
 

 
Author Salzmann, B.B.V.; Vliem, J.F.; Maaskant, D.N.; Post, L.C.; Li, C.; Bals, S.; Vanmaekelbergh, D.
Title From CdSe nanoplatelets to quantum rings by thermochemical edge reconfiguration Type A1 Journal article
Year 2021 Publication Chemistry Of Materials Abbreviated Journal Chem Mater
Volume 33 Issue 17 Pages 6853-6859
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The variation in the shape of colloidal semiconductor nanocrystals (NCs) remains intriguing. This interest goes beyond crystallography as the shape of the NC determines its energy levels and optoelectronic properties. While thermodynamic arguments point to a few or just a single shape(s), terminated by the most stable crystal facets, a remarkable variation in NC shape has been reported for many different compounds. For instance, for the well-studied case of CdSe, close-to-spherical quantum dots, rods, two-dimensional nanoplatelets, and quantum rings have been reported. Here, we report how two-dimensional CdSe nanoplatelets reshape into quantum rings. We monitor the reshaping in real time by combining atomically resolved structural characterization with optical absorption and photoluminescence spectroscopy. We observe that CdSe units leave the vertical sides of the edges and recrystallize on the top and bottom edges of the nanoplatelets, resulting in a thickening of the rims. The formation of a central hole, rendering the shape into a ring, only occurs at a more elevated temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000696553600024 Publication Date 2021-08-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756; 1520-5002 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited (down) 7 Open Access OpenAccess
Notes Hans Meeldijk is kindly acknowledged for helping with electron microscopy at Utrecht University. B.B.V.S. and D.V. acknowledge the Dutch NWO for financial support via the TOP-ECHO grant no. 715.016.002. D.V. acknowledges financial support from the European ERC Council, ERC Advanced grant 692691 “First Step”. D.V. and L.C.P. acknowledge the Dutch NWO for financial support via the TOP-ECHO grant nr. 718.015.002. S.B acknowledges financial support from the European ERC Council, ERC Consolidator grant 815128. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 731019 (EUSMI). Realnano; sygmaSB Approved Most recent IF: 9.466
Call Number UA @ admin @ c:irua:181550 Serial 6839
Permanent link to this record