Thesis (Ph.D.) -- McMaster University, 2001. / Includes bibliographical references. Also available via World Wide Web.

Thesis (Ph. D.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on July 2, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Engineering, Department of Chemical and Materials Engineering, University of Alberta. Includes bibliographical references.

Thesis (M.S.)--Missouri University of Science and Technology, 2010. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed July 29, 2010) Includes bibliographical references (p. 64-67).

Thesis (Ph. D.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Max Deibert. Includes bibliographical references (leaves 74-77).

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Thesis (M. Sc. (Chemistry)) -- University of Limpopo, 2017. / In order to meet the great demand of energy supply globally, there must be a transition from dependency on fossil fuel as a primary energy source to renewable source. This can be attained by use of hydrogen gas as an energy carrier. In the context of hydrogen fuel cell economy, an effective hydrogen generation is of crucial significant. Hydrogen gas can be produced from different methods such as steam reforming of fossil fuels which emit greenhouse gases during production and from readily available and renewable resources in the process of water electrolysis. Hydrogen generated from water splitting using solar energy (photocatalysis) or electric energy (electrocatalysis) has attracted most researchers recently due to clean hydrogen (without emission of greenhouse gases) attained during hydrogen production. In comparison with photocatalytic water splitting directly using solar energy, which is ideal but the relevant technologies are not yet commercialized, electrolysis of water using catalyst is more practical at the current stage. The platinum group noble metals (PGMs) are the most effecting electrocatalysts for hydrogen evolution reactions (HER) but their scarcity and high cost limit their application. In this study, we presented the noble metal free organic-inorganic hybrid composites and their HER electrocatalysis performances were investigated. Polyaniline-metal organic framework (PANI/MOF) composite was prepared by chemical oxidation of aniline monomer in the presence of MOF content for hydrogen production. The properties of PANI, MOF and PANI/MOF composite were characterised for their structure and properties by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), Raman, transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), atomic absorption spectroscopy (AAS), square wave (SWV) and cyclic voltammetry (CV). There was a clear interaction of MOF on the backbone of the PANI matrix through electrostatic interaction as investigated by both Raman and FTIR. The MOF exhibited irregular crystals with further wrapping of MOF by PANI matrix as evidenced by both SEM and TEM analyses. The PANI composite exhibited some nanorods and microporous structure. x The determined energy band gap of the composite was in good agreement with previously reported catalysts for hydrogen evolution reaction (HER). The thermal stability of PANI increased upon addition of MOF. Experiments probing the electrochemical, HER and photophysical properties revealed that the composite was very stable and robust with significant improvement in properties. The resulting composite is a promising low-cost and environmentally friendly hydrogen production material. In this work we also reported about novel poly (3-aminobenzoic acid)-metal organic framework referred as PABA/MOF composite. Spectroscopic characterisations (UV-vis and FTIR) with support of XRD and TGA revealed a successful interaction between PABA and MOF. Morphological characterisation established that PABA is wrapping MOF and the amorphous nature of the materials were not affected. The catalytic effect of PABA and PABA/MOF composites on HER was studied using exchange current density and charge transfer coefficient determined by the Tafel slope method. A drastic increase in catalytic H2 evolution was observed in PABA and composite. Moreover, they merely require overpotentials as low as ~-0.405 V to attain current densities of ~0.8 and 1.5 Am-2 and show good longterm stability. We further demonstrated in the work the electrocatalytic hydrogen evolution reaction of MOF decorated with PABA. These novel MOF/PABA composites with different PABA loading were synthesised via in situ solvothermal synthesis of MOF in the presence of PABA. It was deduced that PABA with different loading amount have an influence on the morphologies, optical properties and thermal stabilities of MOF. Interestingly, the MOF/PABA composites exhibited the great significant on the HER performance and this is potentially useful in HER application for hydrogen fuel cell. / Sasol Inzalo foundation and National Research Foundation of South Africa

Fuel cells have long been seen as an alternative to combustion powered and diesel powered engines and turbines. Production of energy via a fuel cell conversion method can generate up to 60% efficiency in comparison to 30% using a combustion powered engine, with low co-production of harmful side-products. The polymer electrolyte membrane (PEM) adapted for the fuel cell application is one of the main components that determines the overall efficiency. This research project was focused towards novel PEMs, such as sulfonated poly(etheretherketone) or SPEEK, which are cost-efficient and robust with high proton conductivities under hydrated conditions. The degree of sulfonation (DS) of a particular SPEEK polymer determines the proton conducting ability, as well as the long term durability. For SPEEK with high DS, the proton conduction is facile, but the mechanical stability of the polymer decreases almost proportionally. While low DS SPEEK does not have sufficient sulfonic acid density for fast proton conduction in the membrane, the membrane keeps its mechanical integrity under fully saturated conditions. The main purpose of this work was to address both issues encountered with SPEEK sulfonated to low and high DS. The addition of both solid acids and synthetic cross-links were studied to address the main downfalls of the respective SPEEK polymers. Optimization of these techniques led to increased understanding of PEMs and notably better electrochemical performance of these fuel cell materials. Oxo-acids such as tungsten (VI) oxide (WO3) and phosphotungstic acid (PTA) have been identified as candidate materials for creating SPEEK composite membranes. The chemistry of these oxo-acids is well known, with their use as highly acidic catalyst iv centers adopted for countless homogeneous and heterogeneous, organic and inorganic reactions. Uniform dispersion of WO3 hydrate in SPEEK solution was done by a sol-gel process in which the filler particles were grown in an ionomer solution, cast and allowed to dry. PTA composites were made by adding the solid acid directly to a solution of the ionomer and casting. The latter casting was allowed to dry and Cs+ - exchanged to stabilize the PTA from dissolution and leaching from the membrane. The chemical and physical properties of these membranes were characterized and evaluated using mainly conductometric and X-ray photoelectron spectroscopic methods. Composite SPEEK/ PTA membranes showed a 50% decrease in PEM resistance under hydrogen fuel cell testing conditions, while SPEEK/ WO3 composites demonstrated a ten-fold increase in the membrane's in-plane proton conductivity. The chemical and physical properties of these composites changed with respect to their synthesis and fabrication procedures. This study will expound upon their relations.

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