{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/70301"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/70301","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"I. Luminescence Spectroelectrochemistry in Thin Layer Cells. Ii. Kinetics of Mediated Oxidation at a Polymer Modified Electrode","abstract":"I. In general, only one member of a redox couple will be luminescent if redox activity and luminescence originate in the same molecular feature. Moreover, diffusion controlled quenching by the nonluminescent form, through energy or electron transfer, is a likely decay route for a long-lived excited state. Thin layer spectroelectrochemical theory for such a system was derived from the Nernst and Stern-Volmer equations. The tris(2,2'-bipyridine) complex of osmium(III/II) in 1.0 M H(,2)SO(,4) was chosen as a test case. The luminescence Os(bpy)(,3)('2+) *, emitted from an optically transparent thin layer electrode, was monitored as a function of potential. As in the absorbance mode experiment, analysis of the data via Nernst plots proved to be an excellent means of determining n and E('o)', despite the intrusion of photochemical processes in the test system. In addition, the luminescence mode experiment was found to be a useful probe of quenching behavior.","abstract_html":"I. In general, only one member of a redox couple will be luminescent if redox activity and luminescence originate in the same molecular feature. Moreover, diffusion controlled quenching by the nonluminescent form, through energy or electron transfer, is a likely decay route for a long-lived excited state. Thin layer spectroelectrochemical theory for such a system was derived from the Nernst and Stern-Volmer equations. The tris(2,2'-bipyridine) complex of osmium(III/II) in 1.0 M H(,2)SO(,4) was chosen as a test case. The luminescence Os(bpy)(,3)('2+) *, emitted from an optically transparent thin layer electrode, was monitored as a function of potential. As in the absorbance mode experiment, analysis of the data via Nernst plots proved to be an excellent means of determining n and E('o)', despite the intrusion of photochemical processes in the test system. In addition, the luminescence mode experiment was found to be a useful probe of quenching behavior.","abstract_has_math":false,"creators":["Jones, E. Tracy Turner"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-15T23:18:30Z","date_published":"2014-12-15T23:18:30Z","updated_at":"2026-07-22T22:26:02Z","subjects":["Chemistry, Analytical"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8521794"],"render_values":[{"text":"(UMI)AAI8521794","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/70301","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Jones, E. 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In general, only one member of a redox couple will be luminescent if redox activity and luminescence originate in the same molecular feature. Moreover, diffusion controlled quenching by the nonluminescent form, through energy or electron transfer, is a likely decay route for a long-lived excited state. Thin layer spectroelectrochemical theory for such a system was derived from the Nernst and Stern-Volmer equations. The tris(2,2'-bipyridine) complex of osmium(III/II) in 1.0 M H(,2)SO(,4) was chosen as a test case. The luminescence Os(bpy)(,3)('2+) *, emitted from an optically transparent thin layer electrode, was monitored as a function of potential. As in the absorbance mode experiment, analysis of the data via Nernst plots proved to be an excellent means of determining n and E('o)', despite the intrusion of photochemical processes in the test system. In addition, the luminescence mode experiment was found to be a useful probe of quenching behavior.","II. Poly(styrenesulfonate, sodium salt) was spincoated on glassy carbon rotating disk electrodes (RDE's) for use as a matrix for the mediated oxidation of ferrocene-1,1'-disulfonate by electrostatically bound tris(2,2'-bipyridine)osmium(III). This particular mediator-substrate system is designated as case C in the terminology of the Andrieux-Saveant kinetic model for polymer modified electrodes. Case C systems are not catalytic; direct oxidation (reduction) of the substrate precedes oxidation (reduction) of the pre-mediator redox form. However, the existence of two plateau currents facilitates diagnosis of the factors that limit the mediated current. The Andrieux-Saveant theory was applied to voltammetric data obtained at rotating and stationary RDE's and to chronocoulometric data. Analysis of the data revealed that electron self-exchange among the densely packed mediator centers was an efficient process, whereas substrate diffusion through the film was hindered. Mediated oxidation of substrate occurred primarily at the film-solution boundary.","Made available in DSpace on 2014-12-15T23:18:30Z (GMT). No. of bitstreams: 1 8521794.pdf: 3088551 bytes, checksum: c668a91343029ff3cf85f1b1c570d369 (MD5) Previous issue date: 1985","Embargo set by: Seth Robbins for item 70467 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","121 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1985."]},{"key":"dc:title","label":"Title","values":["I. Luminescence Spectroelectrochemistry in Thin Layer Cells. Ii. Kinetics of Mediated Oxidation at a Polymer Modified Electrode"]}]}],"canonical_facts":{"dc:creator":["Jones, E. Tracy Turner"],"dc:date":["2014-12-15T23:18:30Z","10000-01-01","1985"],"dc:description":["I. In general, only one member of a redox couple will be luminescent if redox activity and luminescence originate in the same molecular feature. Moreover, diffusion controlled quenching by the nonluminescent form, through energy or electron transfer, is a likely decay route for a long-lived excited state. Thin layer spectroelectrochemical theory for such a system was derived from the Nernst and Stern-Volmer equations. The tris(2,2'-bipyridine) complex of osmium(III/II) in 1.0 M H(,2)SO(,4) was chosen as a test case. The luminescence Os(bpy)(,3)('2+) *, emitted from an optically transparent thin layer electrode, was monitored as a function of potential. As in the absorbance mode experiment, analysis of the data via Nernst plots proved to be an excellent means of determining n and E('o)', despite the intrusion of photochemical processes in the test system. In addition, the luminescence mode experiment was found to be a useful probe of quenching behavior.","II. Poly(styrenesulfonate, sodium salt) was spincoated on glassy carbon rotating disk electrodes (RDE's) for use as a matrix for the mediated oxidation of ferrocene-1,1'-disulfonate by electrostatically bound tris(2,2'-bipyridine)osmium(III). This particular mediator-substrate system is designated as case C in the terminology of the Andrieux-Saveant kinetic model for polymer modified electrodes. Case C systems are not catalytic; direct oxidation (reduction) of the substrate precedes oxidation (reduction) of the pre-mediator redox form. However, the existence of two plateau currents facilitates diagnosis of the factors that limit the mediated current. The Andrieux-Saveant theory was applied to voltammetric data obtained at rotating and stationary RDE's and to chronocoulometric data. Analysis of the data revealed that electron self-exchange among the densely packed mediator centers was an efficient process, whereas substrate diffusion through the film was hindered. Mediated oxidation of substrate occurred primarily at the film-solution boundary.","Made available in DSpace on 2014-12-15T23:18:30Z (GMT). No. of bitstreams: 1 8521794.pdf: 3088551 bytes, checksum: c668a91343029ff3cf85f1b1c570d369 (MD5) Previous issue date: 1985","Embargo set by: Seth Robbins for item 70467 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","121 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1985."],"dc:identifier":["http://hdl.handle.net/2142/70301","(UMI)AAI8521794"],"dc:subject":["Chemistry, Analytical"],"dc:title":["I. Luminescence Spectroelectrochemistry in Thin Layer Cells. Ii. Kinetics of Mediated Oxidation at a Polymer Modified Electrode"],"dc:type":["text"],"thesis:degree_discipline":["Chemistry"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:02Z"}