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Author Yao, Y.; Ugras, T.J.; Meyer, T.; Dykes, M.; Wang, D.; Arbe, A.; Bals, S.; Kahr, B.; Robinson, R.D. pdf  doi
openurl 
  Title Extracting pure circular dichroism from hierarchically structured CdS magic cluster films Type A1 Journal article
  Year 2022 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 16 Issue 12 Pages 20457-20469  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract (down) Chiroptically active, hierarchically structured materials are difficult to accurately characterize due to linear anisotropic contributions (i.e., linear dichroism (LD) and linear birefringence (LB)) and parasitic ellipticities that produce artifactual circular dichroism (CD) signals, in addition to chiral analyte contributions ranging from molecular-scale clusters to micron-sized assemblies. Recently, we have shown that CdS magic-sized clusters (MSC) can self-assemble into ordered films that have a hierarchical structure spanning seven orders of length-scale. These films have a strong CD response, but the chiral origins are obfuscated by the hierarchical architecture and LDLB contributions. Here, we derive and demonstrate a method for extracting the “pure” CD signal (CD generated by structural dissymmetry) from hierarchical MSC films and identified the chiral origin. The theory behind the method is derived using Mueller matrix and Stokes vector conventions and verified experimentally before being applied to hierarchical MSC and nanoparticle films with varying macroscopic orderings. Each film's extracted “true CD” shares a bisignate profile aligned with the exciton peak, indicating the assemblies adopt a chiral arrangement and form an exciton coupled system. Interestingly, the linearly aligned MSC film possesses one of the highest g-factors (0.05) among semiconducting nanostructures reported. Additionally, we find that films with similar electronic transition dipole alignment can possess greatly different g-factors, indicating chirality change rather than anisotropy is the cause of the difference in the CD signal. The difference in g-factor is controllable via film evaporation geometry. This study provides a simple means to measure “true” CD and presents an example of experimentally understanding chiroptic interactions in hierarchical nanostructures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000888219600001 Publication Date 2022-11-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 17.1 Times cited 8 Open Access Not_Open_Access  
  Notes This work was supported in part by the National Science Foundation (NSF) under Award Nos. DMR-2003431 and CHE-2003586. This work made use of the Cornell Center for Materials Research Shared Facilities, which are supported through the NSF MRSEC program (DMR-1719875). This work is partly supported by Grant PID2021-123438NB-I00 (MCIN/AEI/10.13039/501100011033 and “ERDF vA way of making Europe”) and Grant IT1566-22 (Eusko Jaurlaritza). D.W. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in the Horizon 2020 program (Grant 894254 SuprAtom). S.B. acknowledges financial support from ERC Consolidator Grant No. 815128 REALNANO. B.K. acknowledges NSF award DMR-2003968. We would like to thank Dr. Mark August Pfeifer for help with circular dichroism measurements. Additionally, we would like to thank Professor Luis M. Liz-Marzan for invaluable discussions on chirality. Approved Most recent IF: 17.1  
  Call Number UA @ admin @ c:irua:192070 Serial 7305  
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Author Vlasov, E.; Heyvaert, W.; Ni, B.; Van Gordon, K.; Girod, R.; Verbeeck, J.; Liz-Marzán, L.M.; Bals, S. pdf  url
doi  openurl
  Title High-Throughput Morphological Chirality Quantification of Twisted and Wrinkled Gold Nanorods Type A1 Journal Article
  Year 2024 Publication ACS Nano Abbreviated Journal ACS Nano  
  Volume Issue Pages  
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;  
  Abstract (down) Chirality in gold nanostructures offers an exciting opportunity to tune their differential optical response to left- and right-handed circularly polarized light, as well as their interactions with biomolecules and living matter. However, tuning and understanding such interactions demands quantification of the structural features that are responsible for the chiral behavior. Electron tomography (ET) enables structural characterization at the single-particle level and has been used to quantify the helicity of complex chiral nanorods. However, the technique is time-consuming and consequently lacks statistical value. To address this issue, we introduce herein a high-throughput methodology that combines images acquired by secondary electron-based electron beam-induced current (SEEBIC) with quantitative image analysis. As a result, the geometric chirality of hundreds of nanoparticles can be quantified in less than 1 h. When combining the drastic gain in data collection efficiency of SEEBIC with a limited number of ET data sets, a better understanding of how the chiral structure of individual chiral nanoparticles translates into the ensemble chiroptical response can be reached.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2024-04-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851 ISBN Additional Links  
  Impact Factor 17.1 Times cited Open Access  
  Notes The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.) and from MCIN/AEI/10.13039/501100011033 (Grant PID2020-117779RB-I00 to L.M.L.-M and FPI Fellowship PRE2021-097588 to K.V.G.). Funded by the European Union under Project 101131111 − DELIGHT, JV acknowledges the eBEAM project supported by the European Union’s Horizon 2020 research and innovation program FETPROACT-EIC-07- 2020: emerging paradigms and communities. Approved Most recent IF: 17.1; 2024 IF: 13.942  
  Call Number EMAT @ emat @ Serial 9121  
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Author Zhuo, X.; Mychinko, M.; Heyvaert, W.; Larios, D.; Obelleiro-Liz, M.; Taboada, J.M.; Bals, S.; Liz-Marzán, L.M. url  doi
openurl 
  Title Morphological and Optical Transitions during Micelle-Seeded Chiral Growth on Gold Nanorods Type A1 Journal article
  Year 2022 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume Issue Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract (down) Chiral plasmonics is a rapidly developing field where breakthroughs and unsolved problems coexist. We have recently reported binary surfactant-assisted seeded growth of chiral gold nanorods (Au NRs) with high chiroptical activity. Such a seeded-growth process involves the use of a chiral cosurfactant that induces micellar helicity, in turn driving the transition from achiral to chiral Au NRs, from both the morphological and the optical points of view. We report herein a detailed study on both transitions, which reveals intermediate states that were hidden so far. The correlation between structure and optical response is carefully analyzed, including the (linear and CD) spectral evolution over time, electron tomography, the impact of NR dimensions on their optical response, the variation of the absorption-to-scattering ratio during the evolution from achiral to chiral Au NRs, and the near-field enhancement related to chiral plasmon modes. Our findings provide further understanding of the growth process of chiral Au NRs and the associated optical changes, which will facilitate further study and applications of chiral nanomaterials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000878324400001 Publication Date 2022-10-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 17.1 Times cited 17 Open Access OpenAccess  
  Notes This work was supported by the European Research Council (ERC-AdG-4DbioSERS-787510 to L.M.L.-M. and ERC-CoG-REALNANO-815128 to S.B.) and the MCIN/AEI/10.13039/501100011033 (Grant PID2020-117779RB-I00). X.Z. acknowledges funding from the Juan de la Cierva fellowship (FJC2018-036104-I) and the University Development Fund (UDF01002665, CUHK-Shenzhen). D.L., M.O.-L., and J.M.T. acknowledge funding from the European Regional Development Fund (ERDF) and the Spanish Ministerio de Ciencia, Innovación y Universidades, under Projects PID2020-116627RB-C21 and PID2020-116627RB-C22, as well as from the ERDF/Galician Regional Government as part of the agreement for funding the Atlantic Research Center for Information and Communication Technologies (atlanTTic) and ERDF/Extremadura Regional Government under Projects IB18073 and GR18055. This work was performed in the framework of the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720). The authors acknowledge Dr. Guillermo González-Rubio for providing suggestions for synthesis and Dr. Irantzu Llarena for assisting with the CD measurements. Approved Most recent IF: 17.1  
  Call Number EMAT @ emat @c:irua:191815 Serial 7116  
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Author Skorikov, A.; Albrecht, W.; Bladt, E.; Xie, X.; van der Hoeven, J.E.S.; van Blaaderen, A.; Van Aert, S.; Bals, S. pdf  url
doi  openurl
  Title Quantitative 3D Characterization of Elemental Diffusion Dynamics in Individual Ag@Au Nanoparticles with Different Shapes Type A1 Journal article
  Year 2019 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 13 Issue 13 Pages 13421-13429  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract (down) Anisotropic bimetallic nanoparticles are promising candidates for plasmonic and catalytic applications. Their catalytic performance and plasmonic properties are closely linked to the distribution of the two metals, which can change during applications in which the particles are exposed to heat. Due to this fact, correlating the thermal stability of complex heterogeneous nanoparticles to their microstructural properties is of high interest for the practical applications of such materials. Here, we employ quantitative electron tomography in high-angle annular dark-field scanning transmission electron microscopy (HAADFSTEM) mode to measure the 3D elemental diffusion dynamics in individual anisotropic Au−Ag nanoparticles upon heating in situ. This approach allows us to study the elemental redistribution in complex, asymmetric nanoparticles on a single particle level, which has been inaccessible to other techniques so far. In this work, we apply the proposed method to compare the alloying dynamics of Au−Ag nanoparticles with different shapes and compositions and find that the shape of the nanoparticle does not exhibit a significant effect on the alloying speed whereas the composition does. Finally, comparing the experimental results to diffusion simulations allows us to estimate the diffusion coefficients of the metals for individual nanoparticles.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000500650000115 Publication Date 2019-10-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.942 Times cited 29 Open Access OpenAccess  
  Notes This project has received funding from the European Commission (grant 731019, EUSMI) and European Research Council (ERC Consolidator Grants 815128, REALNANO; 770887, PICOMETRICS; 648991, 3MC; and ERC Advanced Grant 291667, HierarSACol). This project has also received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement 823717, ESTEEM3. W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 797153, SOPMEN). E.B. acknowledges a postdoctoral grant 12T2719N from the Research Foundation Flanders (FWO, Belgium). X.X. acknowledges financial support from the EU H2020-MSCAITN-2015 project 676045, MULTIMAT. The authors also acknowledge financial support by the Research Foundation Flanders (FWO grants G038116N, G026718N, and G036915N).; sygma; esteem3JRA; esteem3reported Approved Most recent IF: 13.942  
  Call Number EMAT @ emat @c:irua:164061 Serial 5379  
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Author Byrnes, I.; Rossbach, L.M.; Brede, D.A.; Grolimund, D.; Sanchez, D.F.; Nuyts, G.; Cuba, V.; Reinoso-Maset, E.; Salbu, B.; Janssens, K.; Oughton, D.; Scheibener, S.; Teien, H.-C.; Lind, O.C. url  doi
openurl 
  Title Synchrotron-based X-ray fluorescence imaging elucidates uranium toxicokinetics in Daphnia magna Type A1 Journal article
  Year 2023 Publication ACS nano Abbreviated Journal  
  Volume 17 Issue 6 Pages 5296-5305  
  Keywords A1 Journal article; Engineering sciences. Technology; Antwerp X-ray Imaging and Spectroscopy (AXIS)  
  Abstract (down) A combination of synchrotron-based elemental anal-ysis and acute toxicity tests was used to investigate the biodistribution and adverse effects in Daphnia magna exposed to uranium nanoparticle (UNP, 3-5 nm) suspensions or to uranium reference (Uref) solutions. Speciation analysis revealed similar size distributions between exposures, and toxicity tests showed com-parable acute effects (UNP LC50: 402 mu g L-1 [336-484], Uref LC50: 268 mu g L-1 [229-315]). However, the uranium body burden was 3 -to 5-fold greater in UNP-exposed daphnids, and analysis of survival as a function of body burden revealed a similar to 5-fold higher specific toxicity from the Uref exposure. High-resolution X-ray fluorescence elemental maps of intact, whole daphnids from sublethal, acute exposures of both treatments revealed high uranium accumulation onto the gills (epipodites) as well as within the hepatic ceca and the intestinal lumen. Uranium uptake into the hemolymph circulatory system was inferred from signals observed in organs such as the heart and the maxillary gland. The substantial uptake in the maxillary gland and the associated nephridium suggests that these organs play a role in uranium removal from the hemolymph and subsequent excretion. Uranium was also observed associated with the embryos and the remnants of the chorion, suggesting uptake in the offspring. The identification of target organs and tissues is of major importance to the understanding of uranium and UNP toxicity and exposure characterization that should ultimately contribute to reducing uncertainties in related environmental impact and risk assessments.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000960129800001 Publication Date 2023-03-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 17.1 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 17.1; 2023 IF: 13.942  
  Call Number UA @ admin @ c:irua:196061 Serial 8631  
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Author Fedoseeva, Y.V.; Orekhov, A.S.; Chekhova, G.N.; Koroteev, V.O.; Kanygin, M.A.; Seovskiy, B.V.; Chuvilin, A.; Pontiroli, D.; Ricco, M.; Bulusheva, L.G.; Okotrub, A.V. pdf  doi
openurl 
  Title Single-walled carbon nanotube reactor for redox transformation of mercury dichloride Type A1 Journal article
  Year 2017 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 11 Issue 9 Pages 8643-8649  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract (down) <script type='text/javascript'>document.write(unpmarked('Single-walled carbon nanotubes (SWCNTs) possessing a confined inner space protected by chemically resistant shells are promising for delivery, storage, and desorption of various compounds, as well as carrying out specific reactions. Here, we show that SWCNTs interact with molten mercury dichloride (HgCl2) and guide its transformation into dimercury dichloride (Hg2Cl2) in the cavity. The chemical state of host SWCNTs remains almost unchanged except for a small p-doping from the guest Hg2Cl2 nanocrystals. The density functional theory calculations reveal that the encapsulated HgCl2 molecules become negatively charged and start interacting via chlorine bridges when local concentration increases. This reduces the bonding strength in HgCl2, which facilitates removal of chlorine, finally leading to formation of Hg2Cl2 species. The present work demonstrates that SWCNTs not only serve as a template for growing nanocrystals but also behave as an electron-transfer catalyst in the spatially confined redox reaction by donation of electron density for temporary use by the guests.'));  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000411918200012 Publication Date 2017-08-07  
  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 11 Open Access Not_Open_Access  
  Notes ; Collaboration between partner institutions was partially supported by European FP7 IRSES project 295180. We are grateful to the bilateral Program “Russian-German Laboratory at BESSY II” for the assistance in XPS and NEXAFS measurements. We acknowledge C. Tollan for proofreading the manuscript. We are grateful to Dr. Y.V. Shubin for XRD measurements of graphite with HgCl<INF>2</ INF>. ; Approved Most recent IF: 13.942  
  Call Number UA @ lucian @ c:irua:146770 Serial 4895  
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