Spectroscopic Srudies of Model Organic Photovoltaic and Organic Light Emitting Diode Organic-Organic' and Metal-Organic Heterojunctions

Persistent Link:
http://hdl.handle.net/10150/194656
Title:
Spectroscopic Srudies of Model Organic Photovoltaic and Organic Light Emitting Diode Organic-Organic' and Metal-Organic Heterojunctions
Author:
Schalnat, Matthew Craig
Issue Date:
2009
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The purpose of this Dissertation was to present fundamental approaches to expand the general knowledge of the chemistry that occurs at both the organic-organic' (O-O') and the metal-organic (M-O) interfaces in organic optoelectronic devices. In order to simplify the interactions in the initial studies presented herein, simple model molecules that represent the larger, highly conjugated molecules used in device construction were considered.UPS, reductive-desorption electrochemistry, and Raman surface spectroscopy were used to determine monolayer characteristics of thiophenol and pentafluorothiophenol on Ag. Proposed interfacial orientations and molecular spacing of the TP and F5TP were proposed. Benzene and hexafluorobenzene (F6-benzene) were then condensed and forcibly dewet onto the monolayers in an effort to understand the solid-liquid interfacial interactions. Benzene films on alkanethiol (UDT) and perfluorinated thiophenol (F5TP) were prone to rupturing, and spectroscopically appeared to be liquid-like in character, while molecular spacing of TP and adsorbed benzene on unmodified Ag template ordered benzene films. Polycrystalline films of F6-benzene forms at the interfaces of TP and unmodified substrates. F6-benzene induces a reorientation of F5TP molecules, but is subsequently unable to induce long range order. F6-benzene on UDT appears liquid-like. These studies show that fixed molecules can stimulate order or disorder at a molecular heterojunction, which may have profound effects in device efficiency.In an effort to begin to understand the complicated reaction chemistry that occurs at the organic-metal interfaces in optoelectronic devices, thin benzene films were reacted with typical device cathode metals, Ag, Mg, Al, and Ca, and studied using Raman vibrational spectroscopy. Ag and Mg form metal clusters and some adduct formation. Al undergoes an insertion reaction, forming a substituted benzene ring. Ca reacts with benzene to form a phenyl radical, which then decomposes the film into regions of ordered graphitic carbon. The results of these studies are attributed to atomic properties of the metal atoms.
Type:
text; Electronic Dissertation
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Chemistry; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Pemberton, Jeanne E.
Committee Chair:
Pemberton, Jeanne E.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleSpectroscopic Srudies of Model Organic Photovoltaic and Organic Light Emitting Diode Organic-Organic' and Metal-Organic Heterojunctionsen_US
dc.creatorSchalnat, Matthew Craigen_US
dc.contributor.authorSchalnat, Matthew Craigen_US
dc.date.issued2009en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe purpose of this Dissertation was to present fundamental approaches to expand the general knowledge of the chemistry that occurs at both the organic-organic' (O-O') and the metal-organic (M-O) interfaces in organic optoelectronic devices. In order to simplify the interactions in the initial studies presented herein, simple model molecules that represent the larger, highly conjugated molecules used in device construction were considered.UPS, reductive-desorption electrochemistry, and Raman surface spectroscopy were used to determine monolayer characteristics of thiophenol and pentafluorothiophenol on Ag. Proposed interfacial orientations and molecular spacing of the TP and F5TP were proposed. Benzene and hexafluorobenzene (F6-benzene) were then condensed and forcibly dewet onto the monolayers in an effort to understand the solid-liquid interfacial interactions. Benzene films on alkanethiol (UDT) and perfluorinated thiophenol (F5TP) were prone to rupturing, and spectroscopically appeared to be liquid-like in character, while molecular spacing of TP and adsorbed benzene on unmodified Ag template ordered benzene films. Polycrystalline films of F6-benzene forms at the interfaces of TP and unmodified substrates. F6-benzene induces a reorientation of F5TP molecules, but is subsequently unable to induce long range order. F6-benzene on UDT appears liquid-like. These studies show that fixed molecules can stimulate order or disorder at a molecular heterojunction, which may have profound effects in device efficiency.In an effort to begin to understand the complicated reaction chemistry that occurs at the organic-metal interfaces in optoelectronic devices, thin benzene films were reacted with typical device cathode metals, Ag, Mg, Al, and Ca, and studied using Raman vibrational spectroscopy. Ag and Mg form metal clusters and some adduct formation. Al undergoes an insertion reaction, forming a substituted benzene ring. Ca reacts with benzene to form a phenyl radical, which then decomposes the film into regions of ordered graphitic carbon. The results of these studies are attributed to atomic properties of the metal atoms.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorPemberton, Jeanne E.en_US
dc.contributor.chairPemberton, Jeanne E.en_US
dc.contributor.committeememberArmstrong, Neal R.en_US
dc.contributor.committeememberWysocki, Vicki H.en_US
dc.contributor.committeememberMcGrath, Dominic V.en_US
dc.contributor.committeememberZheng, Zhipingen_US
dc.identifier.proquest10721en_US
dc.identifier.oclc659753516en_US
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