THE ELECTROCHEMISTY OF SURFACE MODIFIED <10 NM METAL OXIDE NANOPARTICLES

Public Deposited

Downloadable Content

Download PDF
Request Version for Screen Reader
Last Modified
  • March 19, 2019
Creator
  • Roberts, Joseph
    • Affiliation: College of Arts and Sciences, Department of Chemistry
Abstract
  • Chapter One provides a general introduction of the research on metal oxide nanoparticles (MOx), highlighting their synthesis, surface modification, and functionalization. Emphasis is given to the different synthetic route for producing small (<10 nm) MOx nanoparticles with narrow size distributions. Different methods for modifying their surface with small organic molecules are discussed with focus given to silanes and phosphates. Furthermore, functionalizing surface modified nanoparticles for specific functions is addressed, with markers for analytically relevant nanoscale quantification being the primary focus. Chapter Two describes in detail the thermal degradation synthesis used for the generation of small MOx nanoparticles. It demonstrates the versatile of the synthesis by successfully synthesizing ZrO2 and IrO2 nanoparticles. Preliminary work involving the formation of Bi2S3, Bi2O3, and RuO2 nanomaterials is also addressed. The solvothermal synthesis of indium tin oxide (ITO) is also shown for comparison to ITO produced by thermal degradation. Chapter Three details the surface modification of ITO nanoparticles and subsequent electrochemical tagging with a ferrocene moiety. ITO nanoparticles were synthesized via thermal degradation. These nanoparticles underwent a ligand exchange with a covalently binding mondentate silane terminated with a primary amine. Acyl chloride coupling between the amine and chlorocarbonylferrocene provided an electrochemical tag to quantify the level of surface modification. Electrochemisty of the quasi-diffusing nanoparticles was evaluated via cyclic voltammetry (CV), chronoamperometry (CA), and mircodisk electrode (µE) experiments. Chapter Four investigates spectroscopic tagging of ITO and ZrO2 nanoparticles as well as electrochemical tagging of ZrO2 and IrO2 nanoparticles. An unbound azo-dye was synthesized and attempts were made to attach the dye to the surface of ITO nanoparticles. Imine couple between a spectroscopic tag and ZrO2 nanoparticles was also explored, but resulted in very low surface coverages. ZrO2 nanoparticles were also ferrocene tagged using previously discussed siloxane chemistry as well as a new route using click chemistry with an azo-phosphate ligand. A similar approach was taken with hydrolytically synthesized IrO2 and is included for comparison. Chapter Five studies the multivalent electrochemistry of 4 nm magnetite nanoparticles. These nanoparticles are synthesized via thermal degradation and capped with citric acid to make them water soluble. pH dependent electrochemistry was discovered and characterized using cyclic voltammetry, chronoamperometry, and rotating disk electrode experiments. Two separate electrochemical species are present and undergo two irreversible, but separate electrochemical reactions; Fe(II) → Fe (III) and Fe(III) → Fe(II).
Date of publication
Keyword
Subject
DOI
Identifier
Resource type
Rights statement
  • In Copyright
Advisor
  • You, Wei
  • Murray, Royce W.
  • Wightman, R. Mark
  • Jorgenson, James
  • Miller, Alexander
Degree
  • Doctor of Philosophy
Degree granting institution
  • University of North Carolina at Chapel Hill Graduate School
Graduation year
  • 2014
Language
Publisher
Place of publication
  • Chapel Hill, NC
Access right
  • There are no restrictions to this item.
Date uploaded
  • April 22, 2015

Relations

Parents:

This work has no parents.

Items

Thumbnail Title Date Uploaded Visibility Actions
file details Roberts_unc_0153D_14684.pdf 2019-04-11 Public Download