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Supercapacitors are high-power energy storage devices that will play an important role in the transition to a low-carbon society. In recent years, layered electrically conductive metal-organic frameworks (MOFs) have emerged as one of the most promising electrode materials for next-generation supercapacitors. Their crystalline and tuneable structures facilitate structure-performance studies, which are challenging to conduct with traditional porous carbon electrodes. In this work, the electrochemical performances of layered conductive MOFs in supercapacitors are investigated to both improve our understanding of these materials and to develop structure-performance relationships. Having demonstrated that the layered conductive MOF Cu3(HHTP)2 (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) exhibits good performance in supercapacitors, measurements on samples with different particle morphologies reveal that ‘flake’ particles, with small length-to-width aspect ratios, are optimal for these devices. This is due to improved ion accessibility and dynamics through the short pores of the ‘flake’ particles, resulting in a higher power performance compared to particle morphologies with longer pores. Electrochemical quartz crystal microbalance (EQCM) and three-electrode experiments are then performed with Cu3(HHTP)2 and a series of electrolytes with different cation sizes to investigate both the charging mechanism of this MOF and how electrolyte ion size impacts electrochemical performance. It is shown that cations are the dominant charge carriers in Cu3(HHTP)2, with co-ion desorption occurring upon positive charging and counterion adsorption during negative charging. Large ions lead to porosity saturation in MOF electrodes, reducing charge storage and forcing solvent molecules to participate in the charge storage mechanism. The impact of modifying MOF-electrolyte interactions on the electrochemical capacity of layered MOF supercapacitors is then investigated by altering both the electrolyte cation and the MOF electrode functionality. These experiments allow for the systematic probing of the influence of different functional groups on supercapacitor performance, and reveal that MOFs with hydroxy ligating groups, together with Li⁺ electrolytes, constitute the best electrode-electrolyte combination for maximising capacitive performance. Finally, an interlaboratory study is conducted to assess the variability in the reporting of performance metrics across different laboratories. Overall, this work provides unique insights into the performances of layered conductive MOFs for supercapacitor applications, and will guide the design of improved electrode materials for next-generation supercapacitors.

The prevailing rhetoric associated with hedge fund activism is almost universally negative. This thesis provides new evidence of activist hedge fund behavior that contradicts this dominant narrative. The principal idea underpinning the thesis is that the conventional picture of hedge fund activism requires updating to account for two key recent phenomena: activist board representation and environmental, social, and governance (“ESG”) activism. The thesis makes at least four important contributions to academic and policy debates on hedge fund activism. First, through analyzing original hand-collected data on activist hedge fund campaigns, it demonstrates that a relatively new form of activism – activist board representation – tends to involve a longer-term approach to value creation through strategic and operational changes, rather than the short term financial engineering that activist hedge funds are commonly criticized for engaging in. Second, it builds upon the study of activist board representation campaigns to argue that activist hedge funds may be well positioned to play a unique role in ESG activism by nominating specialist climate directors to corporate boards. Third, it outlines how the phenomenon of activist board representation exposes the deficiencies of the independent monitoring board and provides suggestions for potential corporate governance improvements. Finally, it theorizes the incentives behind ESG hedge fund activism, thus providing early insights into this rapidly evolving practice. The thesis is structured as follows: Part I (Chapters 1 and 2) situates hedge fund activism and the role of the board in traditional and contemporary corporate governance debates. Chapter 1 examines the intellectual foundations underpinning the monitoring board as a response to the shareholder-manager agency problem and challenges its continued dominance in light of pressing societal challenges facing corporations. Chapter 2 critiques the narrative of short-termism that is prevalent in politics, the media, and corporate practice, which can obscure learning from the campaigns of activist hedge funds. Part II (Chapters 3 and 4) examines activist hedge fund board representation campaigns. Chapter 3 introduces this new form of hedge fund activism and presents a theory and hypotheses on the potential value associated with this type of activism. Chapter 4 tests the hypotheses presented in the preceding chapter through an empirical study analyzing activist board representation campaigns at S&P 500 companies since 2010. Part III (Chapters 5 to 7) explores ESG activism. Chapter 5 develops a new account of sustainable capitalism using the building blocks of agency theory. It highlights the major shift to passive index investing and ESG investing and analyzes the monitoring shortfall on the part of global asset managers. Chapter 6 discusses ESG hedge fund activism and – building on the theory and the empirical study presented in Part II – proposes that activist hedge funds can play a unique role in a sustainable capitalism framework by nominating specialist directors with climate or energy transition expertise to corporate boards. Chapter 7 considers socially responsible activism and presents a theoretical framework of ESG hedge fund activism.

Block copolymer self-assembly has proven to be an effective route for the fabrication of photonic films and, more recently, photonic pigments. However, despite extensive research on this topic over the past two decades, the palette of monomers and polymers employed to produce such structurally coloured materials has remained surprisingly limited. In this dissertation, a series of biocompatible bottlebrush block copolymers (BBCPs) have been synthesised based upon polyester or polyether macromonomers, including: polylactide, polycaprolactone, or polyethylene glycol. These BBCPs are self-assembled within emulsified droplets into microparticles with a photonic glass architecture that reflects vibrant structural colour. Importantly, a full-colour palette of such ‘photonic pigments’ can be achieved by changing either the BBCP properties (e.g., composition, molecular weight) or the microparticle fabrication conditions (e.g., temperature, time). The relationship between the morphology of the BBCP microparticles and their optical response was ascertained, which allowed for a strategy to enhance the colour purity to be developed. Finally, by investigating BBCPs with similar composition, but different thermal behaviours, it allowed for the mechanism underlying the formation of the internal nanoarchitecture to be understood. Beyond improving the biocompatibility of the BBCPs used for photonics, their end-of-life pathway was also considered. Through the insertion of a degradable linkage into the BBCP backbone, they could be broken down into low molecular weight oligomers under mild conditions. This was demonstrated by incorporating a silyl ether into a polyester-based BBCP, which was exploited in the development of degradable photonic materials based upon lamellar architectures. Overall, the biocompatible and degradable BBCPs developed over the course of these studies will provide the photonics community with a new direction to explore when seeking to resolve the outstanding issue regarding the sustainability of artificial colourants.