Redox-active conjugated polymers for electrochromic and supercapacitive applications

Bulloch, Rayford

Title:

Redox-active conjugated polymers for electrochromic and supercapacitive applications

dc.contributor.advisor	Bottomley, Lawrence A.
dc.contributor.author	Bulloch, Rayford
dc.contributor.committeeMember	Janata, Jiri
dc.contributor.committeeMember	Russo, Paul
dc.contributor.committeeMember	Qin, Dong
dc.contributor.department	Chemistry and Biochemistry
dc.date.accessioned	2017-01-11T13:56:53Z
dc.date.available	2017-01-11T13:56:53Z
dc.date.created	2015-12
dc.date.issued	2015-08-19
dc.date.submitted	December 2015
dc.date.updated	2017-01-11T13:56:53Z
dc.description.abstract	The study of conducting, redox-active polymers has rarely wanted for potential applications, ranging from modulation of optical properties, charge storage, drug release, and more. This subset of redox-active polymers stands in contrast with many of the oft-cited applications for conducting polymers, such as in photovoltaics and transistor technologies, in that the redox-active polymers often take on a much more dynamic or active role in the operation of a device or technology. It is notable that, if care is taken in the design of a redox-active polymer, the same materials may be utilized for both optical and charge storage applications. As a result, this dissertation primarily focuses on the application of a family of redox-active polymers in both electrochromic or charge storage devices, solution processing strategies for modulating optical properties of polymer mixtures, and the stability of these materials with regards to photo-oxidative stress. The presentation of research in this document begins first with the application of conjugated polymers to charge storage applications. Detailed in Chapter 3, a water-processable polymer with a broad electroactive window resembling that of PEDOT is used to modify a non-woven CNT textile via drop casting. Cyclic voltammetry was used to probe supercapacitor devices fabricated using the hybrid CNT-conjugated polymer electrodes, and the capacitive performance was observed to more than double when compared to devices fabricated using the unmodified CNT substrate. Subsequently, efforts made to study color mixing in electrochromic polymers are detailed in Chapters 4 and 5. Mixed color stimuli were produced using various combinations of ECPs following on the cyan-magenta-yellow subtractive color mixing system, first through the use of a “dual active” electrochromic device, and later through the co-processing of ECP mixtures into visually homogenous films. The colorimetric values of the resultant electrochromic films were assessed spectroscopically, and quantified in the CIE Lab* color space. The access of a broad color gamut using polymers representative of the CMY system is demonstrated, as is the ability to “dial in” a color state using the dual active ECD configuration, as is the ability to predict the colorimetric properties of a co-processed ECP mixture via quantification of a mass extinction coefficient for the component ECPs. Finally, the photostability of select ECPs is assessed in Chapter 6. Thin films of two ECPs were encapsulated in both air and argon atmospheres, and exposed to a solar simulator for durations ranging from 24 hours to 1 month. Characterization of these films following irradiation through both spectroelectrochemical and x-ray photoelectron spectroscopic techniques demonstrate that while photo-oxidation is observed to occur under an air environment, encapsulation in an inert atmosphere precludes photo-oxidation and no deleterious effects stemming from long term irradiation are observed. The research detailed in this dissertation demonstrates the varied routes to redox-active, conjugated polymer application.
dc.description.degree	Ph.D.
dc.format.mimetype	application/pdf
dc.identifier.uri	http://hdl.handle.net/1853/56166
dc.language.iso	en_US
dc.publisher	Georgia Institute of Technology
dc.subject	Electrochromic
dc.subject	Polymer
dc.title	Redox-active conjugated polymers for electrochromic and supercapacitive applications
dc.type	Text
dc.type.genre	Dissertation
dspace.entity.type	Publication
local.contributor.advisor	Bottomley, Lawrence A.
local.contributor.corporatename	School of Chemistry and Biochemistry
local.contributor.corporatename	College of Sciences
relation.isAdvisorOfPublication	8f4af367-fd7c-4003-9198-fccb61b6f219
relation.isOrgUnitOfPublication	f1725b93-3ab8-4c47-a4c3-3596c03d6f1e
relation.isOrgUnitOfPublication	85042be6-2d68-4e07-b384-e1f908fae48a
thesis.degree.level	Doctoral