This thesis describes developments towards incorporating spiropyran functionality into metal-organic frameworks (MOFs). Chapter 1 outlines the reported literature concerning the study of photochemistry with respect to MOFs; such materials have demonstrated potential as both alternative environments for the study of photoactivated processes and platforms to integrate photosensitive moieties. Incorporation of photoactive groups into MOFs has enabled these supramolecular materials to be altered chemically and physically via photo-initiated processes. Existing studies into reversible photoswitching groups are largely focussed on azobenzene. The chronological development of azobenzene incorporation into MOFs reflects the evolving strategies of exploiting this functionality to achieve photocontrol over the properties of MOF materials. These advances in accommodating photoswitching azobenzene into MOFs have been applied in reported studies with other photochromic groups and taken into consideration with the work described herein concerning spiropyrans. Chapter 2 focusses on the preparation of a carboxylic acid functionalised salicylaldehyde 3-formyl-4-hydroxybenzoic acid (H2L1), a key precursor in the synthesis of carboxylic acid functionalised spiropyrans. The serendipitous outcome in solvothermal reaction of H2L1 and copper nitrate in dimethylformamide affords {Cu2L12·(DMF)2(H2O)}n (1-Cu-DMF) which has been crystallographically characterised and is further described in this chapter. Channels run through the direction of the crystallographic a-axis of 1-Cu; its connectivity and porosity is retained upon solvent exchange of the single crystals with ethanol and tetrahydrofuran. Gas sorption experiments show 1-Cu exhibits type I adsorption behaviour with a Brunauer-Emmett-Teller (BET) surface area of 948 ± 1 m2 g−1. Notably, 1-Cu adsorbs negligible quantities of methane compared to carbon dioxide and other C2Hn hydrocarbons; the selectivities are confirmed by analysis via the ideal adsorbed solution theory (IAST) and Henry’s law. Of particular importance, 1-Cu demonstrates exceptional selectivity for acetylene, which has applicability in separation technologies for the isolation of acetylene. Chapter 3 details the design and synthesis of a series of carboxylic acid functionalised spiropyrans and bisbenzospiropyrans. These compounds serve as ligand precursors for MOFs but also have interesting photophysical properties as organic compounds, which are studied in this chapter. Condensation of prefunctionalised fragments, H2L1 and carboxylic acid functionalised Fischer’s base 5, afforded a novel dicarboxylic acid functionalised spiropyran H2L2. A second synthetic route to extended ligand precursors, via Suzuki-Miyaura cross coupling of ethyl ester functionalised boronic acids to dibrominated photoactive cores and subsequent hydrolysis, is described. Crystallographic characterisation of the ethyl esters indicates flexibility of the core moieties around the spiro carbon. Comparison of the UV-visible absorption spectra shows the properties of related spiropyrans and bisbenzospiropyrans to be influenced by electronic effects arising from both the type and positioning of the functional groups. The fluorescence quantum yields of novel spiropyrans 13, 15 and H2L5 have been determined as 0.025, 0.032 and 0.068 respectively. Cyclic voltammetric experiments show the electrochemical behaviour of spiropyrans to be influenced primarily by electronic effects related to the type of functional group attached, whereas the electrochemical properties of bisbenzospiropyrans is dominated by electronic effects arising from the positioning of the functional groups. Density functional theory (DFT) calculations of the spectroscopic properties are described and are consistent with experimental observations. Chapter 4 describes investigations to incorporate the carboxylic acid compounds prepared in Chapter 3 into framework materials. To mitigate potential instability problems from using solely photoresponsive and highly flexible components, co-crystallisation with pillaring agents was considered. Reaction of H2L2 with zinc nitrate and a dipyridyl terephthalamide pillaring agent L7 affords coordination network 2 Zn. Two isomers, {Zn(L2)(syn-L7)·(DMF)3(H2O)}n (2-syn-Zn) and {Zn(L2)(anti-L7)·(DMF)3.5(H2O)1.5}n (2-anti-Zn), have been crystallographically characterised; their differences rest upon the conformations adopted by ligand L7. The structure of the 2 anti Zn isomer has higher potential porosity, appearing as rhomboid channels running down the direction of the crystallographic b-axis. The two dimensional sheets of both 2-syn-Zn and 2-anti-Zn are linked in a third dimension through hydrogen bonding interactions between the carboxylate of (L2)2− and amide moiety of L7 in adjacent layers. UV irradiation (325 nm) of single crystals of both forms of 2 Zn initiates a growth in fluorescence of the material observed in situ on a Raman microscope. In situ monitoring of the fluorescence using a 785 nm laser shows a decay over 23 hours to recover the original Raman spectrum of the material. The fluorescence decay can be fitted to a biexponential process; the faster process (13 270 s−1 and 1290 s−1, 2-syn-Zn and 2-anti-Zn respectively) is approximately an order of magnitude greater than the slower process (3980 s−1 and 350 s−1 respectively). DFT calculations suggest the theoretical spectroscopic and electrochemical properties of (L2)2− are not significantly changed by coordination to zinc in 2-Zn. The structures 2-syn-Zn and 2-anti-Zn are the first known examples of spiropyran functionality being incorporated into frameworks.

In this thesis, surface electrocatalysis of several energy-conversion-relevant redox reactions in ionic liquid electrolytes is described. The first oxidation process investigated is the formation of surface oxide films on Pt electrodes by trace water oxidation in protic ionic liquids (PILs). This is followed by investigation of the oxidation of hydrazine (N2H4), formic acid (HCOOH), ethanol (EtOH) and dimethyl ether (DME) in PILs and a description of the role played by surface oxides during each oxidation process. Finally, the electrocatalytic reduction of CO2 at a variety of electrode materials is explored in room temperature aprotic ionic liquids. The data reveal that the surfaces of Pt electrodes become covered with oxide layers due to oxidation of trace water, which is omnipresent in PILs, at positive potentials (E > 1.0 V vs. Pd-H). X-ray photoelectron spectroscopy (XPS) shows that the oxide layers grow to form thick films as the potential is made more positive and as the temperature and water concentration of the PILs are increased. The mechanism and kinetics of oxide film growth are also discussed. Voltammetric analysis shows that the presence of residual surface oxides activates Pt electrodes towards electrooxidation of N2H4. Furthermore, immersion of oxidized Pt electrodes in N2H4-containing PILs deactivates the electrode indicating that N2H4 reacts with the residual surface oxides. Oxidation of HCOOH at Pt catalyst in PILs occurs mainly by dehydration plus COads oxidation at a potential that coincides with the onset of the formation of Pt surface oxides. Compared to Pt electrocatalysts, the overpotential for electrooxidation of HCOOH is higher at Au catalyst but lower at Pd catalyst. Oxidation of trace water in PILs at Pt also plays a pivotal role during the electrocatalytic oxidation of EtOH and DME in the PILs. Oxidation of both EtOH and DME coincides with coverage of the Pt surface by the adsorbed oxide species that helps to activate both processes by oxidizing the adsorbed poisoning CO and CO-like intermediate species via a 'bifunctional' reaction mechanism. Generally, higher overpotentials are observed for each oxidation, and higher activation energies are measured for EtOH oxidation in PILs than in aqueous electrolytes. Finally, it is shown that CO2 electroreduction takes place at lower overpotentials at Au and Ag electrocatalysts than at Cu, Pt and boron doped diamond (BDD) electrodes in the presence of ionic liquid electrolytes. Ag electrocatalysts reduce CO2 at ~0.2 V lower potential when 1-ethyl-3-methylimidazolium ethylsulphate [emim][EtSO4] is used as supporting electrolyte in acetonitrile compared to when the conventional supporting electrolyte tetrabutylammonium hexaflourophosphate [TBA][PF6] is used. CO is a product of CO2 reduction at Ag catalyst and the results highlight that Ag and imidazolium-based ILs could be a promising system for reduction of CO2 to CO at low overpotentials.

Recent technological advances such as the transition from non-renewable to renewable energy have been intimately related to the development of new nanostructured materials. A rational thinking is required for the development of nanomaterials with functional properties by targeting the combination of two or more nanocomponents with different properties, and preparation methodologies ensuring the utilisation of cheaper and abundant materials such as non-precious metals. Therefore, the main motivation of this work is to expand the frontiers of knowledge for the preparation of functional nanomaterials by designing hybrid carbon nanostructures suitable for energy storage applications containing a range of electrochemically active nanocomponents including molecules, nanoparticles and metal coordination polymers. The first chapter describes a general overview of the current approaches within the energy area to prepare uncoupled carbon nanostructures as well as the strategies to combine them with several active components (i.e. molecular metal clusters, nanoparticles and metal coordination polymers). Relevant concepts for this thesis such as electrochemical storage mechanisms, differences between hybrid and composite nanomaterials, synergetic effects and the distinction between ex situ and in situ synthetic approaches are discussed in the introductory chapter. For the sake of clarity, only the most relevant examples of hybrid carbon nanostructures from the literature will be highlighted and discussed. Before describing the hybridisation of carbon with molecules, nanoparticles and metal-coordination polymers, different carbon nanostructures will be analysed on their own due to their outstanding electrochemical properties. After the introductory chapter (Chapter 1), the thesis is followed by two parts: Part A and B. Part A, which is divided in two chapters (Chapter 2 and 3), gathers only carbon nanostructure investigations. In Chapter 2, a facile and solvent-free method is proposed for the development of few-layer graphene nanostructure from carbon tubular nanofibers. In Chapter 3, the synthesis of hollow carbon cages on the surface of carbon nanostructures is thoroughly investigated to elucidate their novel mechanism of formation. The preparation and electrochemical characterization of metal-carbon nanostructures by combining carbon nanostructure with a molecular metal cluster, metal oxide nanoparticles and metal coordination polymers are discussed in Part B. In Chapter 4 the extreme confinement inside hollow tubular carbon nanotubes is investigated to overcome the intrinsic low stability of molecular Mn12 cluster during the electrochemical process. In Chapter 5, the synthesis of metal oxide nanoparticles is carried out in the presence of hollow tubular carbon nanofibers (what we called “in situ synthesis”) where special attention is paid to the carbon surface functionalization. Only the metal oxide-carbon hybrids of interest produced in previous chapter are extensively characterized by electrochemical means to elucidate the effect of confinement with respect to their electrochemical stability. In Chapter 6, a correlation between the structure and chemical composition of a coordinated metal polymer and its electrochemical performance is established in order to gain a better understanding of the alkali intercalation/deintercalation process. One of the key findings in this thesis has been the encapsulation of electrochemically active species, shows promising results not only due to the electron transfer between the guest specie and the host carbon nanostructure, but also to the improvement in the stability during electrochemical cycling. In addition, it has been observed that the electrochemical performance of metal-carbon nanohybrids depends dramatically on the synthetic process that determines the interaction between the nanocomponents and, therefore, the synergetic effect. To sum up, the work developed in this thesis contributes to the area of hybrid metal-carbon nanostructures for energy-storage applications, including new synthetic protocols and strategies, novel hybrid materials with confined electrochemical components, advanced understanding on the electrochemical-structure relationships and important concepts related to durability/recyclability.

Ionic Liquids (ILs) have drawn a great deal of attention as carbon capture agents, and in order to understand them studies must be performed probing the CO2–IL interaction. Many studies have focused upon measuring the solubility of CO2 within ILs, with fewer studies directly probing the CO2 adsorption environments within the IL. Understanding of the adsorption environments is of fundamental for the use of ILs industrially, if they are to be successfully applied within carbon capture and storage devices. Temperature programmed desorption (TPD) has been used to study the CO2–IL interaction within two ionic liquids; 1-octyl-3-methylimidazolium tetrafluoroborate ([C8C1Im][BF4]) and 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C8C1Im][Tf2N]). Experiments were performed utilising low temperature line of sight mass spectrometry (LTLOS MS), ensuring that only species desorbing from the surface are observed. Surfaces were formed through a coadsorption method, where IL was deposited by chemical vapour deposition at a rate of ≈ 1 layer per minute while CO2 was simultaneously leaked into the chamber at pressures between 2×10−8 and 2×10−6 mbar. This study finds that CO2 does not form a monolayer on a gold surface at ≈ 90 K, with no CO2 TPD peak seen for those experiments, showing Edes,CO2 (the activation energy of desorption of CO2) < 24.5 kJ mol−1. When IL and CO2 are coadsorbed the IL is seen to stabilise the CO2, such that a TPD peak for CO2 is seen, with the amount of stabilisation depending upon the IL used. Comparison of experimental TPD curves with calculated TPD profiles, using CO2 states with a range of binding energies, shows that there are multiple CO2 environments within the ILs. The use of TPD allowed the relative populations of these CO2 adsorption environments to be measured, which is not possible using solubility measurements and Henry’s constants, providing insights into the IL–CO2 interaction. CO2 was observed to desorb from sites within the bulk IL, which have activation energies of desorption in the range 24.5 to 43 kJ mol−1. The CO2 was seen to be stabilised most within the [C8C1Im][BF4], giving a stabilisation in Edes of up to 18.5 kJ mol−1. The [C8C1Im][Tf2N] was typically seen to stabilise twice as much CO2 as [C8C1Im][BF4], which is consistent with the experimental Henry’s constants. Further to this a new experimental technique for determining surface structure, utilising high energy X-rays in the total reflection regime, to generate an X-ray standing wave (XSW) and detect the resulting photoelectrons from layered surfaces has been demonstrated. The variable period X-ray standing wave (VPXSW) technique relies on the fact that at low incident angles (typically < 2°) total external reflection of X-rays is observed. The incident and reflected X-rays interact to generate an XSW along the surface normal, with nodes and antinodes at different heights, z, above a reflector for different angles of incidence. By scanning the incident angle of the X-ray from 0° upwards the periodicity of the XSW decreases, resulting in the nodes and antinodes sweeping towards the surface. As this sweeping occurs the nodes and antinodes pass through material adsorbed on the surface of the reflector, and the photoelectron signal fluctuates. Comparing the fluctuations in the measured photoelectron signal to a theoretical model allows surface layering to be detected at larger depths and with a higher information content than with other surface science techniques. This allows distance information, relative to the interfaces between different materials, to be obtained for different chemical species. Data is presented from a surface consisting of the ionic liquid [C8C1Im][BF4] on a Si(001) reflector, held at ≈ 90 K, with a thick IL layer adsorbed on the reflector and a CHCl3 marker layer on top of the IL. Results from the frozen surface indicate a 12 Å layer of CHCl3 and background water had been dosed on top of a 211 Å IL layer. These values agree well with what was expected for this model IL system with a thin marker layer, designed to test the technique. It is therefore shown that VPXSW with photoelectron emission can be used to successfully characterise thin films with thicknesses between 15 Å and ≈ 300 Å with chemical shift specificity, something not possible with current experimental techniques.

There is a growing need for synthetic bone graft materials, which is particularly apparent for procedures requiring impaction bone grafting (IBG), such as revision hip arthroplasty. Currently allograft bone is used that has limited supply and associated risks of transmission of infectious agents. Porous bioresorbable polymeric scaffolds can be created using supercritical carbon dioxide (scCO2). This thesis investigated the use of these scaffolds for impaction bone grafting procedures. Building on previous research within the literature poly(D,L-lactide) (PDLLA) and poly(D,L-lactide-co-glycolide) (PDLLGA) scaffolds of high molecular weight (100 kDa) were investigated for this use. Scaffolds were milled using a standard bone mill and impacted to create porous milled chips of bioresorbable scaffolds and impacted for mechanical shear testing and biocompatibilities. The impaction process used forces equivalent to those experienced during IBG. In vitro cell experiments were used to assess the proliferation and osteoblastic differentiation of mesenchymal stem cells (MSCs) on impacted scaffolds to identify the most promising scaffold compositions. These compositions included pure polymer and polymer:HA microparticle composites. Further experiments using animals (murine and ovine) were then used to investigate the in vivo performance of the scaffolds. A critical sized ovine femoral condyle defect established the osteoinductive and osteoconductive potentials of milled scCO2 foamed PDLLA + 10 wt.% hydroxyapatite (HA) microparticle scaffolds in vivo. The scale-up potential of scCO2 foaming of bioresorbable scaffolds was established using a 1 L vessel. Scaffolds scCO2 foamed using either a 60 ml autoclave or a 1 L vessel were characterised using scanning electron microscopy and micro computed tomography. Scaffolds from different batches were characterised and compared to ensure process repeatability was accounted for. The final chapter investigated differences in the osteoblastic differentiation of MSCs on PDLLA and PDLLGA scaffolds observed in experiments at the start of the study. Spincoated and dipcoated flat films of PDLLA, PDLLGA, and PDLLA:PDLLGA (50:50) were used for in vitro cell culture to remove the effect of morphological differences that affected scCO2 foamed scaffold experiments. Additionally, this chapter investigated the effect of the form of HA using HA nanoparticles andHA microparticles in scCO2 foamed PDLLA:HA composites for in vitro studies.

The aims of this project were to investigate the surface chemistry and morphology of processed tea leaves the techniques of atomic force microscopy (AFM), scanning electron microscopy (SEM) and time of flight secondary ion mass spectrometry (ToF-SIMS). Data from the spectra obtained by ToF-SIMS was also analysed using principal component analysis (PCA). Further experimentation was performed on tea leaves by the addition of diluted samples of aromas, methyl salicylate, trans-2-hexenal and linalool and examining these leaves using depth profiling to discover how far into the leaf the aroma had penetrated and if there was any connection between the chemistry and size of the aromas and how far they penetrated. A general characterisation of the tea leaves was performed in Chapter 3 where layers of waxes of a comparable size were observed on both green and black tea leaves with AFM, as were micro-crystals on black tea and areas showing two distinct types of interaction between the cantilever tip and the surface of a green tea leaf indicating different surface properties. SEM images revealed a visual difference between green and black tea leaves, where the black tea leaves had more debris on the surface and greater changes in topography due to the different processing methods. The presence of lipids and epicuticular waxes were observed on the surface of the tea leaves using the ToF-SIMS. In Chapter 4 the effects of infusion in hot water on the morphology and surface chemistry of the tea leaves are examined. SEM revealed structural damage to the leaves from 30 seconds of infusion and this increased with infusion time, resulting in the formation of holes in the cutin on the adaxial surface of the tea leaf. By examining positive and negative ToF-SIMS spectra and using PCA, a change in surface chemistry could be detected from 15 seconds of infusion. The intensity of C3H5O2+ peaks in the spectra increased as infusion time increased, indicating that the waxy cuticle of the leaf surface had been removed revealing the underlying epidermal cell layer. Peaks associated with octadecenoic and octadecanoic acids were shown to have a reproducible effect on the positioning of the different infusion times within the PCA plots. Though chemical changes can be detected at 15 seconds, the first 30 seconds of infusion were found to be responsible for the majority of the chemical changes on the surface. Taken together these data indicate that the melting of the cutin layer, primarily within the first 30 seconds of infusion may be related to the release of flavour, aroma and constituents such as polyphenols. The penetration into the leaf of aroma molecules was examined in Chapter 5. Diluted solutions of methyl salicylate, linalool and trans-2-hexenal were added to tea leaves and then examined using depth profiling with ToF-SIMS. For the first time a leaf was depth profiled using a C60. The presence of trans-2-hexenal was detected in the palisade mesophyll layer of the leaf as was methyl salicylate, but to a smaller intensity. Methyl salicylate showed partitioning in diffusion across the cuticle with a large intensity in the cuticle and also in the interface between the epidermis and palisade mesophyll layers. Linalool was present on the surface of the leaf and showed partitioning in the cuticle of the tea leaves. As trans-2-hexenal was the smallest and least lipophilic of the three aromas examined it is theorized that the smaller the size of the aroma molecule plays a key role in the penetration of the dehydrated leaves.

This thesis details the synthesis and study of molecular species designed to form supramolecular assemblies, in particular for surface deposition purposes. The first chapter gives a brief introduction to supramolecular chemistry concepts and the basis on which this project is built. The importance of non-covalent bonding interactions to form complex architectures capable of self-assembly is discussed, in particular hydrogen bonds and pi-pi interactions with a series of examples from the literature to illustrate the work that has been accomplished over the past few years in various fields of supramolecular chemistry and nanotechnology in particular. The present project aims at the design, the synthesis and the characterisation of two different groups of compounds, namely p-terphenyl tetracarboxylic acid derivatives and manganese based single molecule magnets. The former are dealt with in the second chapter of the present thesis. The scientific background and the recent results obtained following the surface deposition of p-terphenyl-3,5,3',5'-tetracarboxylic acid are explained and discussed in the introduction. The focus of the research is to design and synthesise similar derivatives, i.e capable of self-assembling to produce similar ordered arrays on surfaces as observed for the parent molecule, but bearing some specific functional groups that are anticipated to either induce a change in the observed assembly process or even impart the molecular functionality upon the assembly. The third chapter of the thesis describes the synthesis and functionalisation of manganese-based single molecule magnets, which are believed to be promising candidates for future applications such as high-density data storage. The crystal structures of some derivatives are discussed and a crystallographic comparative study between the as-synthesised derivatives and literature examples is detailed. In addition, the magnetic properties of selected complexes are discussed and compared. Finally, the results resulting from surface deposition studies that have been carried out in collaboration with the School of Physics and Astronomy at the University of Nottingham are presented in the last section of this chapter.

Polymers have been used as biomaterials for nearly a century and have recently become the material of choice for use in tissue engineering. However, the classes of biodegradable and biocompatible polymers available for use in biomedical devices and as tissue engineering scaffolds are limited. This lack of available polymers with suitable properties could inhibit the development of biomedical devices with improved biocompatibility and hinder the growth of the fledgling tissue engineering field. Researchers in the polymer and biomaterials fields have tried to remedy this problem by applying combinatorial and high throughput methods developed in drug discovery to the search for new polymers. A recent advance has been the development of combinatorial polymer libraries printed as microarrays. This format allows the polymers to be readily screened for their cell adhesion and differentiation properties, allowing ‘hit’ materials with ideal properties to be identified. However, without knowledge of the surface properties of these novel polymers it is impossible to rationalise their biological properties. The surface characterisation of such microarrays presents numerous practical problems included small sample size, sample number and even analysis of such large amounts of data. It is the aim of this thesis to develop methods for the characterisation of the surface chemistry, wettability and protein adsorption properties of polymers in situ in microarray format and within realistic timeframes. The thesis will explore multivariate statistics in the form of PCA and PLS as methods of analysing the large amount of data acquired. The first part of this thesis describes the surface chemical analysis of a polymer microarray using ToF-SIMS and XPS. A comparison of the polymers’ surface to bulk chemistries by XPS indicated that 64 % of the polymers had a surface chemistry which differed from the bulk. This reinforces the need for characterisation of the polymers’ surface chemistries, as it is obvious that this can not be inferred from their bulk chemistries. ToF-SIMS imaging was shown to be an ideal method of studying the distribution of specific ion species across the array and to confirm that the microarray was printed in the intended layout. Principal component analysis is shown to be an ideal technique to analyse both ToF-SIMS and XPS spectral data from the arrays, allowing similarities and differences in the surface chemistry of the polymers to be easily visualised. To estimate the surface energies of the arrayed polymers it is necessary to use picolitre volume droplets to make contact angle measurements. In Chapter 4 it is shown that contact angle measurements taken from picolitre volume water droplets are equivalent to those measured from more conventional microlitre droplets. In Chapter 5 picolitre contact angle measurements are used to estimate the polar and dispersive surface energies of a polymer microarray, which has been specifically designed to exhibit a maximum range of surface energy values. The analysis shows that there is indeed great variation in the WCA and polar surface energies of the polymers, demonstrating the power of intelligently designed combinatorial libraries. To understand the chemical basis of this large range of surface energies the results are compared to surface chemical data from ToF-SIMS and XPS. Surface atomic and functional data from XPS is unable to provide any definitive explanations for the range of surface energies observed. However, information about the molecular structure of the surface from ToF-SIMS gives an insight into what surface functionalities are responsible for high and low surface energies. In Chapter 6 PLS regression is investigated further as a method for investigating surface structure-property relationships in large polymer libraries. Specifically two issues are investigated: the influence of sample number on the results obtained and the ability of PLS to make quantitative predictions. The ToF-SIMS and surface energy dataset discussed in Chapter 5 is used for this task. It is demonstrated that the results obtained from PLS models of large polymer libraries are equivalent to those obtained from much smaller datasets, in terms of the ions identified in the regression vector. Using various test sets of polymers it is shown that there is a limit to the predictive ability of PLS: specifically, as the difference between the training and test sets increases, the quality of the predictions decreases. Potential problems with data pre-processing and re-scaling are also identified. In the final experimental chapter two methods are described for investigating protein adhesion and adsorption to micro-arrayed polymers using AFM and fluorescently labelled proteins. Both methods indicate a wide range of protein adsorption properties within the group of polymers analysed. A good correlation between the two sets of data was observed which appears to validate both methods. In summary the work described in this thesis has demonstrated the feasibility of the characterisation of the surface chemistry, energetics and protein adsorption properties of a micro-arrayed polymer library within realistic time-frames. PCA and PLS have been shown to be useful tools for analysing the data obtained. It is hoped that the methods described in this thesis will allow the biological data from polymer microarrays to be rationalised using the surface properties of the polymers, allowing the design of new biomaterials.

The self-assembly of two-dimensional molecular systems is of significant interest, offering an insight into the fundamental interactions which drive the formation of complex supramolecular structures. A careful choice of the molecular 'building blocks' for such self-assembled systems potentially allows the design and production of nanoscale architectures with pre-determined geometries and specific chemical functionalities. Within this thesis the two-dimensional structures formed by the self-assembly of complex organic molecules, deposited on an Au(111) surface held in an ultrahigh vacuum (URV) environment, are studied using a combination of scanning tunnelling microscopy (STM), photoelectron spectroscopy (PES), molecular dynamics (MD), and density functional theory (DFT) techniques. A UHV electrospray deposition (URV-ESD) technique is employed to facilitate the introduction of thermally labile molecules into the URV environment. Bi-molecular networks, formed from perylene tetracarboxylic diimide (PTCDI) and melamine, have previously been observed to assemble on the Au(111) surface. Several more complex phases are reported here, as characterised by S'I'M, with the balance between isotropic and anisotropic interactions giving rise to a variety of structures. Chemical functionality may be added to these networks by incorporating functionalised derivatives of PTCDI. Alternative structures produced by altering the shape of the molecular 'building blocks' are also discussed. The URV-ESD technique is demonstrated here to be compatible with the deposition of the fullerene C60,the single molecule magnet Mn12012(02CCR3h6(H20)4 (Mn12(acetate)16), and porphyrin based oligomers (P4 and P6) and polymers (Pn). The URV-ESD of C60on the clean AU(ll1) surface, and on a surface prepatterned with a PTCDI/melamine network, results in similar structures to those previously observed to be produced by sublimation. Mn12(acetate)16 and the porphyrin oligomers and polymers represent complex molecules which are thermally labile and possess, respectively, novel magnetic and electronic properties. Mn12(acetate) 16is observed to form filamentary aggregates due to the anisotropic nature of the molecule-molecule and molecule-substrate interactions, while P4, P6 and Pn form highly ordered close-packed domains driven by the interdigitation of the alkyl chains attached to the porphyrin cores. The findings presented within this thesis demonstrate that self-assembled molecular structures can be understood in terms of intermolecular interactions, and that for systems containing complex molecules the molecule-molecule interaction potential can lead to the formation of novel structures.

CHAPTER 1: A background to the techniques of matrix isolation, liquid xenon solution and flash photolysis with fast IR detection is presented. The application of infrared spectroscopy in structural studies of metal carbonyl compounds is also discussed. Chapter 2: Photolysis of((nu5-C5R5)Pt(CO))2 (R=H, Me) in frozen gas matrices results in production of ((nu5-C5R5)Pt2(mu-CO)). 13CO enrichment and polarised photochemistry show that the photoproduct contains a single symmetrically bridging CO group. Photolysis of (CpNi(mu-CO))2 in frozen gas matrices results in formation of CP2Ni2(CO) with a terminal CO ligand. The stability these dinuclear photoproducts in room temperature solution has been investigated using fast TRIR spectroscopy. Photolysis in CO matrices leads to M-M bond cleavage and reaction with CO to give Pt(CO)4 or Ni(CO)4 as the final product. CHAPTER 3: Photolysis of Os2(CO)9 or OS2(CO)8- - (mu-nu1, nu1-C2H4) in frozen gas matrices leads to formation of Os2(CO)8, which has only terminal CO groups. The thermal and photochemical reactivity of Os2(CO)a towards CO, N2 and C2H4 is investigated. Photolysis using plane polarised light provides confirmation of the C2v structure of Os2(CO)9, and gives evidence favouring a D2h structure for Os2(CO)8. Prolonged UV photolysis of Os2(CO)9 in CO matrices leads to cleavage of the Os-Os bond and production of Os(CO)5. CHAPTER 4: The mechanism of the photochemical deoligomerisation of FpSiMe2SiMe3 is investigated using a variety of techniques. The reaction is shown to proceed via two photochemical steps. Primary CO-loss is followed by intramolecular trapping to give a silyl(silylene) intermediate. The second step involves expulsion of an SiMe2 fragment and coordination of a ligand. L. to give CpFe(CO)(L)SiMe3 (L = CO, PPh3,C2H4 or N2). CHAPTER 5: A study of the photochemistry of Fp-disilyl complexes containing beta-silyl hydrogens implies beta-H transfer from Si to Fe as the dominant process following photodissociation of CO. The product, a metalladisilacyclopropane or nu2-disilene complex, is implicated as an intermediate in the photochemical formation of FpH in this system. CHAPTER 6: The experimental techniques and spectrometers used in this research are described. along with a discussion of the theory and advantages of FTIR spectroscopy.