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Three-dimensional x-ray computer tomography images were obtained of electrospun poly(acrylonitrile) electrodes for a flow battery. The materials were imaged before and after carbonization. Information about the internal morphology; local fiber size and porosity, was analyzed and provided key insights into both the electrospinning and carbonizing processes. It was found that traditional imaging techniques may not be suitable for materials generated through electrospinning as it is a highly dynamic process. The fiber size tended to vary throughout the process while the porosity was relatively constant. Viscous flow was modelled through the material using the Lattice Boltzmann Method and the 3D flow fields that resulted provided further information about the role of heterogenous features on the performance of an electrospun electrode in a flow battery. The local porosity of the material had the largest effect on the material's flow dynamics.

Polymeric layered carbon nitrides were investigated for use as catalyst support materials for proton exchange membrane fuel cells (PEMFCs) and water electrolyzers (PEMWEs). Three different carbon nitride materials were prepared: a heptazine-based graphitic carbon nitride material (gCNM), poly (triazine) imide carbon nitride intercalated with LiCl component (PTI-Li+Cl-) and boron-doped graphitic carbon nitride (B-gCNM). Following accelerated corrosion testing, all graphitic carbon nitride materials were found to be more electrochemically stable compared to conventional carbon black (Vulcan XC-72R) with B-gCNM support showing the best stability. For the supported Pt, Pt/PTI-Li+Cl- exhibited the best durability with only 19% electrochemical surface area (ECSA) loss versus 36% for Pt/Vulcan. Superior methanol oxidation activity was observed for all gCNM supported Pt catalysts on the basis of the catalyst ECSA. Preliminary results on IrO2 supported on gCNM using a PEMWE cell revealed an enhancement in the charge-transfer resistance as the current density increases when compared to unsupported IrO2. This may be attributed to a higher active surface area of the catalyst nanoparticles on the gCNM support.

A novel PdIr/C supported alloy nanoparticle catalyst has been developed for use in the hydrogen oxidation reaction (HOR) at the anode of an Alkaline Anion Exchange Membrane (AAEM) fuel cell. The catalyst has been characterised using Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDX) and Synchrotron X-ray Powder Diffraction (SXPD). Electrochemical testing suggests it has a comparable activity for HOR as Pt/C and is a good candidate for use on the anode of an AAEM fuel cell.