Symposium 1: Functional Metastructures and Nanomaterials: Properties, Fabrication and Modeling III

16:40 Invited talk : Fluorescence-Tunable Gold Clusters Capped with Lipoic Acid-Polyethylene Glycol Ligands

Hedi Mattoussi

Florida State University (USA)

We combine the use one-pot aqueous growth route with the photochemically sensitive nature of lipoic acid molecules to prepare fluorescent clusters made of gold (AuNCs) with tunable emission ranging from the blue to the red region of the optical spectrum. The growth strategy exploits the natural UV-induced photochemical transformation of LA-based ligands to thiols and thiol radical byproducts that exhibit great affinity to metal-rich complexes. The materials were characterized using UV-Visible absorption and fluorescence spectroscopy, TEM and DOSY-NMR.
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17:00 Invited talk : Quantum Confined Semiconductor Nanocrystals: Elevated Temperature Performance and Sensing Application

Richard Schaller

Northwestern University (USA)

We examine colloidal semiconductor nanocrystals upon temperature elevation, reveal reversible as well as irreversible exciton quenching pathways, and investigate the role of surface termination on exciton integrity with temperature. This work points to strategies to improve upon material performance in high temperature applications. We have also exploited these material properties in biological sensing applications where we make use of the large absorption cross-sections and high optical stability to produce a selective, stable, fast and sensitive all-optical pathogen detection assay.
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17:20 Invited talk : Two-color hybrid plasmonic nano-emitter

X. Zhou (1),X. Yang (2),X. Sun (2),H. V. Demir (2),A. Vial (1),L. le Cunff (1),A. S. Bisht (1),G. P. Wiederrecht (3),R. D. Schaller (3),S. Jradi (1),J. Plain (1),G. Colas des Francs (4),R. Bachelot (1)

(1)University of Technologie of Troyes (France) , (2)Nanyang Technological University (Singapore) , (3)Argonne National Laboratory (USA) , (4)Bourgogne University (France)

In plasmonic light-emitting hybrid nanosystems, the monochromaticity of the light emission prevents possible switchable color. Here, we demonstrate two-color anisotropic plasmonic nano-emitters that were fabricated via plasmonic photo-polymerization. By using different QD-doped solutions, quantum emitters of different colors can be positioned selectively in different orientations in the close vicinity of the metal nanoparticles. As a result, the dominant emitting wavelength can be controlled with the direction of the incident polarization.
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17:40 Invited talk : Using Patterned Arrays of Metal Nanoparticles to Probe Plasmon Enhanced Luminescence of CdSe Quantum Dots

Jixin Chen (1),Yang-Hsiang Chan (2),Stacey E. Wark (2),Stephanie L. Skiles (2),Dong Hee Son (2),James D. Batteas (2)

(1)Ohio University (USA) , (2)Texas A-M University (USA)

In this conference, I am presenting a paper published on ACS Nano. A nanostructure with layers of CdSe quantum dots and gold/silver nanoparticles separated by polymers has been fabricated to probe the plasmon-enhanced photoluminescence (PL) of quantum dots (QDs) by confocal microscopy. The results curves of the PL enhancement as a function of the QD-metal separation was analyzed with a model that composed of a quenching factor and an enhancement factor.
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