Records |
Author |
Feld, A.; Weimer, A.; Kornowski, A.; Winckelmans, N.; Merkl, J.-P.; Kloust, H.; Zierold, R.; Schmidtke, C.; Schotten, T.; Riedner, M.; Bals, S.; Weller, P.D., Horst |
Title |
Chemistry of Shape-Controlled Iron Oxide Nanocrystal Formation |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
13 |
Issue |
13 |
Pages |
152-162 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Herein we demonstrate that meticulous and in-depth analysis of the reaction mechanisms of nanoparticle formation is rewarded by full control of size, shape and crystal structure of superparamagnetic iron oxide nanocrystals during synthesis. Starting from two iron sources – iron(II)- and iron(III) carbonate -a strict separation of oleate formation from the generation of reactive pyrolysis products and concomitant nucleation of iron oxide nanoparticles was achieved. This protocol enabled us to analyze each step of nanoparticle formation independently in depth. Progress of the entire reaction was monitored via matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and gas chromatography (GC) gaining insight into the formation of various iron oleate species prior to nucleation. Interestingly, due to the intrinsic strongly reductive pyrolysis conditions of the oleate intermediates and redox process in early stages of the synthesis, pristine iron oxide nuclei were composed exclusively from wustite, irrespective of the oxidation state of the iron source. Controlling the reaction conditions provided a very broad range of size- and shape defined monodisperse iron oxide nanoparticles. Curiously, after nucleation star shaped nanocrystals were obtained, which underwent metamorphism towards cubic shaped particles. EELS tomography revealed ex post oxidation of the primary wustite nanocrystal providing a full 3D image of Fe2+ and Fe3+ distribution within. Overall, we developed a highly flexible synthesis, yielding multigram amounts of well-defined iron oxide nanocrystals of different sizes and morphologies. |
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000456749900017 |
Publication Date |
2018-12-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
54 |
Open Access |
OpenAccess |
Notes |
The authors gratefully acknowledge financial support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Projektnummer 192346071 – SFB 986 and the excellence cluster ‘The Hamburg Centre for Ultrafast Imaging – Structure, Dynamics and Control of Matter at the Atomic Scale’ (by grant EXC 1074) S.B. and N.W. acknowledge financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS) and from the Research Foundation Flanders (FWO, Belgium) through Project fundings G038116N. Dr. Volker Sauerland for his support in calibrating the MALDI-TOF spectra. Almut Bark for measuring XRD (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ecas_sara |
Approved |
Most recent IF: 13.942 |
Call Number |
EMAT @ emat @c:irua:155716UA @ admin @ c:irua:155716 |
Serial |
5073 |
Permanent link to this record |
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Author |
Scarabelli, L.; Schumacher, M.; Jimenez de Aberasturi, D.; Merkl, J.‐P.; Henriksen‐Lacey, M.; Milagres de Oliveira, T.; Janschel, M.; Schmidtke, C.; Bals, S.; Weller, H.; Liz‐Marzán, L.M. |
Title |
Encapsulation of Noble Metal Nanoparticles through Seeded Emulsion Polymerization as Highly Stable Plasmonic Systems |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
29 |
Issue |
29 |
Pages |
1809071 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The implementation of plasmonic nanoparticles in vivo remains hindered by important limitations such as biocompatibility, solubility in biological fluids, and physiological stability. A general and versatile protocol is presented, based on seeded emulsion polymerization, for the controlled encapsulation of gold and silver nanoparticles. This procedure enables the encapsulation of single nanoparticles as well as nanoparticle clusters inside a protecting polymer shell. Specifically, the efficient coating of nanoparticles of both metals is demonstrated, with final dimensions ranging between 50 and 200 nm, i.e., sizes of interest for bio-applications. Such hybrid nanocomposites display extraordinary stability in high ionic strength and oxidizing environments, along with high cellular uptake, and low cytotoxicity. Overall, the prepared nanostructures are promising candidates for plasmonic applications under biologically relevant conditions. |
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000467109100024 |
Publication Date |
2019-02-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301X |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
19 |
Open Access |
OpenAccess |
Notes |
L.S. and M.S. contributed equally to this work. This work was supported by the Spanish MINECO (Grant MAT2017-86659-R), by the German Research Foundation (DFG, Grant LA 2901/1-1) and by the European Research Council (Grant 335078 COLOURATOM to S.B). The authors acknowledge funding from the European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M). L.S. acknowledges funding from the American-Italian Cancer Foundation through a Post-Doctoral Research Fellowship. D.J.d.A. thanks MINECO for a Juan de la Cierva fellowship (IJCI-2015-24264). J.P.M. was financed by Verband der Chemischen Industrie e.V. (VCI). The authors thank Dr. Artur Feld, Dr. Andreas Kornowski and Stefan Werner (Institute of Physical Chemistry, University of Hamburg) for their support. |
Approved |
Most recent IF: 12.124 |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:160710 |
Serial |
5190 |
Permanent link to this record |