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Functionalised carbon nanomaterials are desired in a wide variety of applications; however, it is important to ensure that any potential adverse effects are assessed and understood alongside the emerging nanotechnology. Although there have been numerous toxicity evaluations on different CNMs, with the focus on as-synthesised materials rather than functionalised materials; clarification of potential toxic effects of specific CNMs’ physicochemical properties are still unclear, impart to the lack of model materials with tailored properties, with which to compared and contrast. In this thesis, a thermochemical functionalisation methodology has been applied to as-synthesised, bulk carbon nanomaterials without damaging their intrinsic carbon framework. Compared to conventional approaches, this method has the advantages of using simple protocol, which are readily scalable and versatile to wide range of nanocarbons and functionalities. A comprehensive library of water-dispersible functionalised carbon nanomaterials were produced which include single-walled and multi-walled carbon nanotubes, graphene nanoplatelets and carbon black nanoparticles. These materials were prepared with well-controlled physicochemical properties, such as dimensions, surface charge and hydrophobicity etc. A series of nanotoxicological studies using the model materials have been carried out by our collaborators, employing various biological systems, with particular focus on their respiratory impact. In addition, the underlying mechanism of the thermochemical functionalisation methodology was explored, building and developing upon previous work.

This study examined project stakeholders‘ expectations of a funded enterprise coaching project designed to alleviate symptoms of deprivation in Corby. A mixed method approach of Q study and semi-structured interviews was used to reveal the expectations, behaviours and evaluation of four main groups of stakeholders - the project clients (13); the project delivery team (6); Corby Borough Council (3); and the project funder (1) - a total of 23 participants. Results of the Q study analysis revealed three factors, indicating that stakeholders have different expectations about the project. The semi-structured interviews demonstrated that although stakeholders tried to promote their expectations, their influences were significantly limited by their power to influence decision making. Apart from the dominant project funder, there was no rigorous connection between stakeholders‘ expectations and the project evaluation criteria (time, cost and quality). Triangulated results led to the development of a unique model that incorporates broader stakeholder expectations and promotes distributed power and communication in the decision making process. This model further assists in drawing attention to emerging conflicts and problems as a constant process is developed for future project management.

Two-dimensional (2D) materials, referring to materials being just one atom thick, prove to be attractive not only in fundamental research but also in applications. Graphene, a single layer of carbon atoms arranged in hexagonal rings, is just the first among other materials (including hexagonal boron nitride and molybdenum disulfide) that could be isolated into mono-atomic layers. The presented thesis investigates proton transport through atomically thin two-dimensional materials. While the electronic, optical and mechanical properties of graphene and other 2D materials have been intensely researched over the past decade, much less is known on the interaction of these crystals with protons. It has been reported that most of the defect free two dimensional materials are impermeable to nearly all gases, molecules and ions. Whether proton, the smallest positively charged ion, could transport through two dimensional materials at a low energy level remains unknown. This work investigates proton transport through 2D materials, including graphene, hexagonal boron nitride and molybdenum disulfide, in two different systems: Nafion/Pd solid system and liquid/liquid interface system, both of which provided consistent results. Our results suggest that proton can transport through the interatomic spacings in the lattice of single layer BN and graphene, while single layer MoS2 is impermeable to protons. Single layer BN is the most conductive to protons among the 2D materials investigated in this thesis. Lower proton conductance of graphene is due to its delocalized π electrons while proton impermeability of MoS2 is due to the three atomic layers structure. Moreover, proton transfer is greatly facilitated by the deposition of platinum nanoparticles on the proton conductive 2D membranes to such a degree that platinum decorated BN seems to present negligible resistance to the transfer of protons through its lattice.

Tailoring the heteronanostructures of nanoscale materials to tune their structure-property relations for desirable interfacial energetics is imperative for their catalytic, optoelectronic and electrochemical applications. Current PhD thesis develops a facile, yet “green” synthesis route that uses laser ablation synthesis in solution in tandem with galvanic replacement reaction (tandem LASiS-GRR) as a one-pot, one-step technique for manufacturing diverse and complex heteronanostructures of metal oxides, hydroxides, nanocomposites (NCs), and nanoalloys (NAs). The scientific concept here is that the non-equilibrium thermodynamics and kinetics of high-energy LASiS-GRR can be tuned by laser parameters and solvent chemistry to form complex NCs/NAs of tailored sizes/shapes, metastable structures and compositions. The results indicate that the presence or absence of solution-phase oxygen (O2) during LASiS on bulk Cobalt (Co) produces cobalt monoxide (CoO) or, single crystal beta-cobalt hydroxide (β-cobalt hydroxide), nanoparticles (NPs) respectively as the metastable states. These intermediates finally transform into cobaltosic oxide (Co3O4) NPs, along with the formation of Co3O4 nanorods with enhanced localized surface plasmon resonance (LSPR) at high pH. In contrast, LASiS-GRR on Co in Potassium tetrachloride palatinate (K2PtCl4) salt solution produces NCs of PtCo NAs embedded in cobalt oxide (CoOx) matrices (i.e., PtCo/CoOx). These NCs exhibit outstanding bifunctional electrocatalytic activities for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) along with better stability, which are attributed to the shrunken lattice constants of alloyed PtCo that promote oxygen adsorption, and synergic “spillover” effects from high surface area CoOx matrices that promote symbiotic adsorption/desorption of intermediate species. Subsequent acid wash of the aforementioned PtCo/CoOx NCs results in spherical PtCo NAs with tunable sizes, compositions and degrees of alloying. These NAs exhibit uniformly alloyed core encapsulated in few nanometers of Pt-rich shell. Such core-shell NA structures along with high degrees of alloying promote their outstanding electrocatalytic ORR activities in acid electrolytes. Finally, preliminary results for LASiS-GRR on bulk zinc/titanium (Zn/Ti) in silver nitrate (AgNO3) salt solution indicate the formation of plasmonic Ag NPs embedded in zinc oxide (ZnO) or titania (TiO2) matrices, with the majority of Ag NPs covered by spherical TiO2 that are anti-corrosive in acid.

The role of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) solubility on the evolution of structure and function in solvent annealed organic photovoltaics is quantitatively investigated. ODCB solvent vapor distribution during the solvent uptake process is simulated on a 3-D profile. Determination of solvent uptake in the P3HT/PCBM mixture shows that the evolution of the morphology during solvent annealing (SVA) takes much longer than the diffusion of the solvent vapor into the sample. The evolution of P3HT crystallinity, as well as the growth of PCBM aggregates, in the solvent annealed thin films is observed by Grazing Incidence Wide Angle X-ray Scattering (GIWAXS) and Atomic Force Microscopy (AFM) respectively. For the solvents that have a finite P3HT solubility, P3HT crystallinity initially increases then decreases with longer SVA time, where P3HT solubility of the annealing solvent plays a significant role in the variation of crystallinity. However, 2-Chlorophonel (2-CP) vapor, which has negligible P3HT solubility but high PCBM solubility, also exhibits an increase in P3HT crystallinity upon solvent annealing a P3HT/PCBM thin film. PCBM aggregates grow continuously with SVA, a process that is modulated by the PCBM solubility in the annealing solvent. Moderate PCBM aggregation correlates to improved power conversion efficiency (PCE) of the solvent annealed thin film. For the samples annealed using solvents that prefer P3HT, PCE benefits from further SVA after P3HT crystallinity peak time, which is ascribed to the additional PCBM aggregation; whereas the PCBM preferred solvents induce excess PCBM phase separation at further SVA times, which limits exciton dissociation hence PCE performance. Also, a flow SVA chamber is designed to realize in-situ light scattering experiments, where preliminary experiments using this apparatus are reported.