Please use this identifier to cite or link to this item: doi:10.22028/D291-28983
Volltext verfügbar? / Dokumentlieferung
Title: Oriented Gold Nanorods and Gold Nanorod Chains within Smectic Liquid Crystal Topological Defects
Author(s): Rožič, Brigita
Fresnais, Jérôme
Molinaro, Celine
Calixte, Joseph
Umadevi, Shivakumar
Lau-Truong, Stephanie
Felidj, Nordin
Kraus, Tobias
Charra, Fabrice
Dupuis, Vincent
Hegmann, Torsten
Fiorini-Debuisschert, Celine
Gallas, Bruno
Lacaze, Emmanuelle
Language: English
Title: ACS nano
Volume: 11
Issue: 7
Startpage: 6728
Endpage: 6738
Publisher/Platform: ACS
Year of Publication: 2017
Publikation type: Journal Article
Abstract: We show that the use of oriented linear arrays of smectic A defects, the so-called smectic oily streaks, enables the orientation of gold nanorods (GNRs) for a large range of GNR diameters, ranging from 7 to 48 nm, and for various ligands. For the small GNRs it enables oriented end-to-end small chains of GNRs when the density is increased from around 2 GNRs/μm2 to around 6 GNRs/μm2. We have characterized the orientation of single GNRs by spectrophotometry and two-photon luminescence (TPL). A strongly anisotropic absorption of the composites and an on-off switching of GNR luminescence, both controlled by incident light polarization, are observed, revealing an orientation of the GNRs mostly parallel to the oily streaks. A more favorable trapping of GNRs by smectic dislocations with respect to ribbon-like defects is thus demonstrated. The dislocations appear to be localized at a specific localization, namely, the summit of rotating grain boundaries. Combining plasmonic absorption measurements, TPL measurements, and simulation of the plasmonic absorption, we show that the end-to-end GNR chains are both dimers and trimers, all parallel to each other, with a small gap between the coupled GNRs, on the order of 1.5 nm, thus associated with a large red-shift of 110 nm of the longitudinal plasmonic mode. A motion of the GNRs along the dislocations appears as a necessary ingredient for the formation of end-to-end GNR chains, the gap value being driven by the balance between the attracting van der Waals interactions and the steric repulsion between the GNRs and leading to interdigitation of the neighboring ligands. We thus obtain electromagnetic coupling of nanorods controlled by light polarization.
DOI of the first publication: 10.1021/acsnano.7b01132
URL of the first publication:
Link to this record: hdl:20.500.11880/27865
ISSN: 1936-0851
Date of registration: 24-Sep-2019
Faculty: NT - Naturwissenschaftlich- Technische Fakultät
Department: NT - Chemie
Professorship: NT - Prof. Dr. Tobias Kraus
Collections:SciDok - Der Wissenschaftsserver der Universität des Saarlandes

Files for this record:
There are no files associated with this item.

Items in SciDok are protected by copyright, with all rights reserved, unless otherwise indicated.