Electrochemical and spectroelectrochemical investigations of interfacial electrode processes

Electrode interfaces are critical players in the development of medical, industrial, and energy-related technologies and a thorough understanding of the surface electrochemistry is required to design better devices and materials. Analytical methods for studying electrode surfaces in situ vary widely and give information ranging from chemical speciation to electron transfer properties. Electrochemical methods using the analyte of interest as the working electrode provide vital interfacial properties such as kinetics, mass transport, and thermodynamics of electrode processes across the entire interface. In this dissertation, such techniques are shown to determine the charge transport properties and mechanisms of a redox-active solid thin film, successfully applying redox polymer theory to model how charge transport is affected by redox dopant loading. To investigate local structural changes at interfaces, this dissertation explores the incorporation of surface-enhanced Raman spectroscopy (SERS) to electroanalytical experiments. I demonstrate the viability of scanning electrochemical microscopy (SECM) to control local surface pH at a self-assembled monolayer and SERS to track the resulting structures. To broaden the application of electrochemical SERS to carbon-based electrodes, I demonstrate a hybrid nanoparticle-graphene substrate and use it to characterize the electrochemical reduction of anthraquinone-2,6-disulfonate on graphene. Further, I show the capability of SECM to induce SERS-detectable changes at these carbon substrates and suggest further possible research directions for this and other projects using coupled Raman-SECM. Overall, this work demonstrates several new methods for deeper fundamental understanding of complex electrode interfaces, probing charge transport, local solution perturbation effects, and adsorption chemistry.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2022

Author dc:creator

• Hatfield, Kendrich O'Donaghue

Contributors dc:contributor

• Rodríguez-López, Joaquín
• Murphy, Catherine
• Jain, Prashant K
• Han, Hee-Sun

• Electrochemistry
• Surface-enhanced Raman spectroscopy
• Scanning Electrochemical Microscopy
• Thin film electrodes

Statement dc:rights

• Copyright 2022 Kendrich Hatfield

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/115644

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F115644