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Carbon Nanomaterials As Electrodes In Thermogalvanic Cells For Waste Heat Recovery, Mark S. Romano

University of Wollongong Thesis Collection 1954-2016

A possible solution to the worlds growing energy problem is to improve the efficiency of energy conversion processes by harnessing waste heat. Thermogalvanic systems, also known as thermocells, allow the direct conversion of thermal to electrical energy. A device consists of two electrodes operating at different temperatures and placed in contact with a redox-based electrolyte. The temperature dependence of the redox reactions generates a potential difference such that when the thermocell is connected to an external circuit, current and power may be extracted.

The initial part of this work focused on an investigation of K3Fe(CN)6/K4Fe(CN)6 concentration (in aqueous media) as …

Mathematical Modelling For Carbon Nanotubes And Peptide Nanotubes, Fainida Rahmat

University of Wollongong Thesis Collection 1954-2016

Nanostructures such as carbon and peptide nanotubes have attracted considerable interest in research in nanotechnology due to their remarkable properties and potential applications. A proper understanding of the intermolecular interactions between these nanostructures is crucial for the practical realization of novel nanodevices. In this thesis, we construct mathematical models to determine the interaction energy for these nanostructures. In particular, we consider the noncovalent interaction energies, which significantly contribute to the determination of molecular equilibrium configurations, and determine the mechanical properties of the nanostructure. Here, we employ the continuum approach which assumes that atoms are smeared over the entire surface of …

Nanostructured Carbon Electrodes, Dennis Antiohos

University of Wollongong Thesis Collection 1954-2016

Supercapacitors are promising energy storage and power output technologies due to their improved energy density, rapid charge-discharge cycle, high cycle efficiency and long cycle life. Free standing poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate) / single walled nanotube films have been characterised by scanning electron microscopy, Raman spectroscopy and thermo-gravimetric analysis to understand the physical properties of the films. Films with varying compositions of poly(3,4-ethylenedioxythiophene) / poly(styrene sulfonate) and single walled nanotubes were compared by electrochemical impedance spectroscopy, cyclic voltammetry and galvanostatic charge / discharge to understand their electrochemical properties. A comparison of the results shows that having single walled nanotubes dispersed throughout the …

Controlled Drug Delivery From Polypyrrole Powered By Enzymatic Bioelectrodes, Willo Grosse

University of Wollongong Thesis Collection 1954-2016

Galvanically coupling enzymatic bioelectrodes with drug loaded conducting polymers to develop a controlled drug delivery system is investigated. The system is designed to be a novel and sophisticated approach to in vivo drug delivery for the treatment of epilepsy. There is a suite of anti-epileptic drugs (AEDs) that are extremely effective at suppressing seizure activity however; their use is restricted due to debilitating side effects. As such, it is of interest to develop novel drug release methods to deliver the AEDs directly to the target area in the brain and in small doses to minimise, and ideally eliminate, the side …

Thermally Sensitive Conducting Hydrogels, Nuchalee Thipmonta

University of Wollongong Thesis Collection 1954-2016

This thesis aims to synthesize thermally sensitive electrically conducting hydrogels. Poly(N-isopropylacrylamide) (PNIPAM) is the most common thermally responsive hydrogel and exhibits a lower critical solution temperature (LCST) which can be reversibly switched from a hydrophilic, swollen state to a hydrophobic, collapsed state. For constructing thermally sensitive electrically conducting hydrogels, this project is limited to the use of single-walled carbon nanotubes (SWNTs) as these materials are especially good candidates from a variety of carbon nanotubes because of they have relatively low bending stiffness. PNIPAM hydrogel composites containing SWNTs are expected to be promising materials because they can combine two or more …

Functionalized Carbon Nanotubes As The Platforms In The Dopamine And Ascorbic Acid Biosensors, Jie Zhao

University of Wollongong Thesis Collection 1954-2016

The main goal of this study was to design and develop novel carbon nanotube (CNT) based platforms as biosensors for simultaneous voltammetric detecting dopamine (DA) and ascorbic acid (AA). The use of such novel nanostructured electrode platforms will enable the development of affinity-based biosensors for disease diagnostics and therapy monitoring. Such bio-sensing systems will perform sensitively and selectively for detection of the neurotransmitters/neurochemicals by utilizing certain CNT material structure and introducing various functional groups, thus enhance response to the specific bioanalytes. The electrical devices are extremely useful for delivering the diagnostic information in a fast and simple way.

A highly …

Synthesis, Characterisation And Applications Of Carbon Nanotube Membranes Containing Macrocycles And Antibiotics, Luke Joshua Sweetman

University of Wollongong Thesis Collection 1954-2016

This thesis explores the development of novel carbon nanotube membranes (buckypapers, BPs) incorporating antibiotic and macrocyclic ligands as dispersants. Membranes were obtained by vacuum filtration of dispersions containing the functional dispersants, or the surfactant Triton X-100 (Trix), and either single-walled carbon nanotubes (SWNTs) or multi-walled carbon nanotubes (MWNTs). The homogeneity and stability of SWNT dispersions was first evaluated using a combination of UV-vis- NIR spectrophotometry, optical microscopy and Raman spectroscopy.

Microanalytical data and energy dispersive X-ray spectra were obtained for the SWNT buckypapers, and provided evidence for retention of dispersant molecules within the structure of the membranes. The electrical conductivities …

Investigation Of New Carbon Based Real-Time Dosimeters, Cameron Stanton

University of Wollongong Thesis Collection 1954-2016

Current and emerging photon radiation therapy modalities require dosimetry with tissue-equivalence, high spatial resolution, the possibility to measure surface dose and dose inside the target, and preferably the ability to use the system in-vivo and online. In fact, the high dose gradients afforded in both intensity modulated radiation therapy (IMRT) and microbeam radiation therapy (MRT) require the small size of solid-state dosimeters for the accurate quantification of absorbed dose to tissue both pre-treatment and for real-time quality assurance purposes. However, with much of the advances made in solid-state dosimetry having focused on the use of silicon as the base sensing …

Wet-Spinning Of Nanostructured Fibres, Rouhollah Jalili

University of Wollongong Thesis Collection 1954-2016

The development of nanostructured fibres from organic conductors produced via wet-spinning technique is described in this thesis. The main objectives are (1) to develop the fundamental knowledge and understanding of organic conductors such as conducting polymers, single walled carbon nanotubes (SWNTs) and graphene, (2) to create multifunctional nanostructured fibres based on PEDOT:PSS/SWNTs and liquid crystals of graphene oxide (LC GO), (3) to study the effects of spinning formulation on the electrical conductivity, electrochemical performance and mechanical properties of the nanostructured fibres and (4) possible applications of these structures in fibre based energy storage systems.

A novel continuous wet-spinning approach was …

Nano-Composite Materials From Carrageenan, Conducting Polymers And Carbon Nanotubes, Ali Aldalbahi

University of Wollongong Thesis Collection 1954-2016

Carrageenan is an anionic, water soluble biopolymer which is well known for its gelforming capabilities. To date it has been mainly employed in the food processing industry and for medical applications. This project aimed to assess its ability to form composite materials with conducting fillers such as carbon nanotubes (CNTs) and conducting polymers (CPs).

As a result of the research conducted for this thesis, the biopolymer carrageenan was found to act as an excellent dispersant of CNTs and as a dopant during the polymerisation of CPs such as polyaniline (PANi) and polypyrrole (PPy). In addition, carrageenan was shown to have …

Mathematical Modelling For Three Problems In Nanotechnology, Thien Tran-Duc

University of Wollongong Thesis Collection 1954-2016

The non-covalent interaction energy in multimolecular systems is a topic of considerable interest in nanotechnology, since it holds the key to understanding their equilibrium configurations and mechanical properties. For systems involving large numbers of atoms and molecules, the determination of the interaction energy becomes especially complicated and it provides a major challenge for computational chemistry. This thesis develops mathematical models resulting in analytical formulae for the interaction energy in three specific areas of nanotechnology.

Aromatic interactions are generally found to stabilize the global structure of proteins and the double helical structure of DNA, and they also play an important role …

Novel Graphene Composite Materials, Widsanusan Chartarrayawadee

University of Wollongong Thesis Collection 1954-2016

Graphene is another form of carbon material which has many outstanding properties such as large surface area, high Young’s modulus, high charge carrier mobility, good thermal conductivity and excellent transmittance properties. Graphene can be synthesized by different methods and can be readily prepared in both solid powder and colloidal aqueous dispersion. Furthermore, graphene as a carbon material has potential to form composites with other materials such as metal nanoparticles, conducting polymer and other forms of carbon material such as carbon nanotubes. As part of this research, graphene was prepared from graphene oxide as a colloidal aqueous dispersion; keeping in mind …