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The Formation and Characterization of Mesoscopic J- and H-aggregates with Controlled Morphologies by the Co- and Templated Assembly of Cyanine Dyes

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Date Issued:
2018
Abstract/Description:
The supramolecular aggregates of ?-conjugated molecules have become an area of great interest to the scientific community in recent years for their promise in biosensors and optoelectronic devices. Among various supramolecular aggregates, J- and H-aggregates of ?-conjugated dye molecules are particularly interesting because of their unique optical and excitonic properties that are not given by individual molecules. H-aggregates are composed of dye molecules in a face-to-face stacking, giving rise to a blue-shifted absorption band compared with the monomer band and a strong emission quenching. In contrast, J-aggregates represent an edge-to-edge stacking of dye molecules, showing a red-shifted absorption band with respect to the monomer band and a strong fluorescence emission. However, the use of J- and H-aggregates in biosensors and optoelectronic devices remains a challenge because of the difficulty of controlling their sizes and morphologies. In this dissertation, we develop two different paths for controlling the size and morphology of J- and H-aggregates. First, we show that the co-assembly of cyanine dyes and lithocholic acid (LCA) in ammonia solution can lead to the formation of mesoscopic J- and H-aggregate fibers, depending on the condition under which the co-assembly occurs. Second, we report the formation of mesoscopic J-aggregate tubes by using the preformed LCA tubes as a template. The structure, optical, and electronic properties of these J- and H-aggregate fiber and tubes are studied as a function of temperature. Finally, we exploit their applications as photo-induced electron transfer supramolecular probes for the detection of dopamine, an important neurotransmitter in central and peripheral nervous systems.
Title: The Formation and Characterization of Mesoscopic J- and H-aggregates with Controlled Morphologies by the Co- and Templated Assembly of Cyanine Dyes.
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Name(s): Rhodes, Samuel, Author
Fang, Jiyu, Committee Chair
Jiang, Tengfei, Committee Member
Dong, Yajie, Committee Member
Florczyk, Stephen, Committee Member
Pang, Sean, Committee Member
University of Central Florida, Degree Grantor
Type of Resource: text
Date Issued: 2018
Publisher: University of Central Florida
Language(s): English
Abstract/Description: The supramolecular aggregates of ?-conjugated molecules have become an area of great interest to the scientific community in recent years for their promise in biosensors and optoelectronic devices. Among various supramolecular aggregates, J- and H-aggregates of ?-conjugated dye molecules are particularly interesting because of their unique optical and excitonic properties that are not given by individual molecules. H-aggregates are composed of dye molecules in a face-to-face stacking, giving rise to a blue-shifted absorption band compared with the monomer band and a strong emission quenching. In contrast, J-aggregates represent an edge-to-edge stacking of dye molecules, showing a red-shifted absorption band with respect to the monomer band and a strong fluorescence emission. However, the use of J- and H-aggregates in biosensors and optoelectronic devices remains a challenge because of the difficulty of controlling their sizes and morphologies. In this dissertation, we develop two different paths for controlling the size and morphology of J- and H-aggregates. First, we show that the co-assembly of cyanine dyes and lithocholic acid (LCA) in ammonia solution can lead to the formation of mesoscopic J- and H-aggregate fibers, depending on the condition under which the co-assembly occurs. Second, we report the formation of mesoscopic J-aggregate tubes by using the preformed LCA tubes as a template. The structure, optical, and electronic properties of these J- and H-aggregate fiber and tubes are studied as a function of temperature. Finally, we exploit their applications as photo-induced electron transfer supramolecular probes for the detection of dopamine, an important neurotransmitter in central and peripheral nervous systems.
Identifier: CFE0007412 (IID), ucf:52718 (fedora)
Note(s): 2018-05-01
Ph.D.
Engineering and Computer Science, Materials Science Engineering
Doctoral
This record was generated from author submitted information.
Subject(s): Bile Acids -- Cyanine Dyes -- J-Aggregate -- H-Aggregate
Persistent Link to This Record: http://purl.flvc.org/ucf/fd/CFE0007412
Restrictions on Access: campus 2019-11-15
Host Institution: UCF

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