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Over the past several years, online disinformation and misinformation concerning climate change have gained substantive attention within the scientific community. However, while the dynamics that drive the circulation of false online information have been analysed extensively, it remains unclear whether (and how) this phenomenon can be counteracted. This research project analyses the emerging role of bottom-up mobilisations as a form of noise-reduction, thereby examining how social movements may deploy peer-produced communication narra- tives to counteract the circulation of online disinformation and misinformation relating to climate change. To investigate this communication dynamic, this research applies techniques from computational social sciences to an original dataset of ≈ 250k Facebook posts produced by two movements that best embody this novel and innovative generation of radical envi- ronmental activism: Extinction Rebellion and Fridays for Future. The central thesis of this project forwards two original contributions to the fields of climate change communication and social movement studies. First, it analyses the emergence of a new generation of radical climate change movements and the significance of this new development in climate activism (Chapter II). Second, it offers interdisciplinary empirical evidence on how radical climate movements can act as a bottom-up force for what I term ‘epistemic activism’. It presents a theoretical framework where activist-led, peer-produced communication can provide a coun- tering force to both vertical disinformation and horizontal misinformation. It quantitatively analyses two channels through which these forms of false information can be opposed. For reducing vertical disinformation, this work assesses the use of naming and shaming against information polluters (Chapter III), while for horizontal misinformation, it evaluates the dissemination of scientific counter-narratives (Chapter IV). Ultimately, this thesis shows that the two movements under analysis engage extensively in epistemic activism, with great potential to influence the online climate change debate positively.

The world increasingly depends on batteries to store renewable energy and use that same energy in our vehicles and portable communication devices. This puts exceeding pressure on global resources. We need batteries that charge faster and live longer, such that we can use less resources. Faster charge and longer life are currently limited by the negative electrode, typically graphite, because fast charging would push the potential into the regime of hazardous and cycle-life degrading lithium plating. The ideal potential for fast charge would be low, but just above the around 1 V reduction potential of the electrolyte. Niobium-based metal oxides have the optimal electronegativity to strike this balance, with a nominal potential around 1.6 V, charging rates >5C and a cycle-life projected over 10,000 cycles. Chapter 1 shows that the exact potential can be tuned further by changing the average oxidation state through substitution of Nb5+ with for example W6+ or Ti4+. The range of average oxidation states then directly spans a material phase space classed by anion-to-cation ratios of 2.33 ≤ *y* < 2.82. These "off-stoichiometric" ratios typically force the unit cell to rearrange into an ordered balance of *y*=3 ReO3-type blocks of corner-sharing octahedra that have ample window sites to rapidly intercalate many lithium-ions, interspaced with *y*=2.5 crystallographic shear planes of edge-sharing octahedra that add stability and electronic conductivity to the structure, and anchored at their corner by *y*=2 regions of tetrahedra or edge-sharing octahedra. The influence of this structure on cell performance is relatively unknown. Numerous publications exist on individual members of this Wadsley-Roth (WR) material family, but gaps in theory and varying experimental conditions make it impossible to compare. The aim of this thesis is to provide a fair and fundamental comparison across this material class, relating compositional and structural properties to cell thermodynamics and kinetics that can then be used to optimise the material selection and model any full-scale cell geometry. In total 16 different compounds were synthesised with comparable geometrical parameters. Subsequently, they were fully parameterised with various electrochemical tests. Current theory is still too firmly based on traditional metal plate electrodes. Because the WR materials allow extreme conditions of high currents and could be tuned over an extensive structural and compositional range, their study forms an excellent opportunity to modernise the fundamental understanding of the thermodynamics and kinetics of intercalation lithium-ion batteries, in general, and in relation to structural and compositional parameters. Chapter 2, on thermodynamics and energy density, introduces fundamental principles of configurational entropy to explain the steep bends at the cell potential ends and the detailed peaks in the cyclovoltammogram. Density function theory (DFT) exposed a site filling order and structural straightening. Via molecular orbital theory this was then related to enthalpic effects of relatively steeper potential regions due to progressively poorer charge-compensation and relatively poor shielding, but also relatively flatter potential regions related to metal-to-metal repulsion and pseudo Jahn-Teller effects at the block edge. Owing to their increased edge-sharing, low *y* materials could thus reach lower potentials without reaching the voltage cut-off earlier. Low *y* materials thus exhibit high energy density, particularly considering that they also consist of more lightweight elements. The structural straightening upon reduction was identified as the crucial mechanism that provides a competitive energy density to the WR material. The first cycle data and DFT also revealed the mechanism that tetrahedral linkages are irreversibly trapping lithium and that they can be left out of the structure to achieve nearly 100% first cycle efficiencies. On the other hand, the study in Chapter 3 of their intercalation kinetics through temperature-dependent GITT and PEIS with novel application of the compensation effect shows that lower *y* is at the cost of lower entropy of the diffusion pathways, such that their intercalation diffusion coefficients are lower. In general, the compensation effect and the effect of entropy can not be underestimated, while the effect of activation enthalpy could be misleading. Various PEIS, cyclovoltammetry, PITT and GITT techniques had to be critically reviewed and stripped from metal-plate concepts, to identify the formation of film layers and the trends in diffusion. The charge transfer reaction rate and lithium intercalation diffusion were identified as the main contributors to loss, limiting the charge/discharge rate. However, this study observed that the chemical lithium intercalation diffusion coefficient increases with rate. This surprising effect is no longer adequately described by the conventional mass-transfer theory and suggests effects of non-equilibrium driving forces, excited lithium hopping, lattice vibrations and energy barrier softening. Such a mechanism is essential to explain the high rate performance of WR materials and intercalation materials in general and provides an important direction for future theory and experimental research. All in all, this study showed a tradeoff between energy and rate, with TiNb2O7, Zn2Nb34O87 and PNb9O25 as winners. Independent of the tradeoff, performance could be further improved in the future with the substitution of lightweight cations, and by increasing the crystallographic entropy with multiple cations. In general, this work identified several new applications of theory to the modern battery cell, which will hopefully become more widely applied and further underpinned by in-situ direct observation methods on the particle level. All the theory and full parameterisation methods above were combined into a full cell continuum model in Chapter 4, that not only validates these approaches but also allows the design, verification and prediction of any commercial format multilayer cell geometry. This paves the way for this new class of ultra fast-charge long-life batteries that can power more of the world, with fewer batteries.

Mining sector always comes under severe scrutiny due to their negative impacts towards society and environment. Several studies contributed to reduce these impacts exists in the mining operations, in the development, studies also started to explore various assessment mechanism to understand the mining firm's sustainability impact. Among such assessment strategies, sustainability indicators gained huge momentum in recent years specifically with mining operations. This study considers one such area to focus, sustainability indicator analysis in mining. There are several sustainability indicators were introduced in the literature, which makes the consideration of sustainability indicators as a chaotic process for practitioners. Considering the fact, this study sought to explore the influential sustainability indicator and their corresponding sustainability dimension with the case context of China. As a major global manufacturer, China explores different ways to do a sustainable mining business for their long-term growth and this study could impact on their sustainable development goals roadmap. Different sustainability indicators considering mining were collected from the existing studies and further validated and categorized with expert opinions under their respective dimensions of sustainability (economy, environment, and society). The validated sustainability indicators were evaluated through a multi criteria decision making tool, DEMATEL. The inputs for the analysis were collected from a Chinese mining case company. The results revealed the influential sustainability indicator for Chinese mining sector. By understanding the most and least influential indicators, the Chinese mining practitioners can eliminate the strategies to motivate the least influential indicator and improve the strategies to motivate most influential indicator. China University of Petroleum, Beijing

A promising alternative to either chemical or sensible heat energy storage systems is the latent heat thermal energy storage (LHTES) due to its superiority in many design aspects such as the high storage capacity as well as chemical stability and relatively low cost. Due to its potentials to overcome the problems of instability and intermittency of energy through using phase change material (PCM), latent heat energy storage has been used in a variety of practical applications. However, most of the phase change materials possess poor thermal conductivity resulting in modest charging/discharging rate. To overcome this deficit, high porosity metal foam is used to improve the overall thermal conductivity of the phase change materials leading to enhancing the heat transported, and hence, promoting the PCM melting and solidification.This proposal has been utilised to improve the performance of a latent heat thermal storage system having a parallel/staggered tube-bundle structure filled with paraffin as a PCM, where an open-cell copper foam is compounded to the paraffin wax. The PCM unit is charged/discharged using a relatively hot/cold water stream flowing across the tube-bundle units. The feasibility of such a configuration is examined numerically through simulating the proposed PCM-metal foam composite units and their surrounding shell computationally. The ANSYS Fluent CFD commercial code has been employed to solve the volume averaged Navier-Stokes equations taking into account the local thermal non-equilibrium expected to occur between the solid metal foam matrix and the paraffin phase-change material. The impact of some design and operating parameters on the charging/discharging performance has been tested including the water flow strength as well as the tube-bundle configuration. The currently proposed design of LHTES system has been found not only easy to configure but practically efficient as well, where the charging/discharging rate can be remarkably boosted through wise selection of design parameters.

Thin-film technologies have been part of the rapidly-expanding solar photovoltaics (PV) market for many years, led by cadmium-telluride (CdTe) and copper‑indium‑gallium-selenide (CIGS). However, their environmental impacts remain largely unknown, particularly considering state-of-the-art CIGS manufacturing techniques. This study estimates the life cycle environmental impacts of CIGS PV installations in the UK and Spain, including balance-of-system components, using real manufacturing data. It also analyses newly-developed CIGS, replacing the cadmium sulphide (CdS) buffer layer with zinc oxysulphide (Zn(O,S)) via atomic layer deposition (ALD). The results show that UK installations have 72% higher impacts than those in Spain, including climate change (25.1 vs 14.6 g CO2 eq./kWh). The inverter and electrical components are the main contributors (46% on average), followed by the PV modules (41%). In comparison to CdTe, mono-Si and multi-Si PV, CIGS has 6%-90% lower impacts in 16 out of 18 categories, including climate change (16%-50% lower). However, metal depletion is five times higher, and land use 12%-31% greater. The replacement of CdS has a small but positive effect, demonstrating that cadmium can be eliminated from the CIGS life cycle without environmental penalties. These results will be of interest to PV manufacturers and policy makers, indicating improvement opportunities and areas for policy intervention.

Australia’s centre-right Coalition government’s ‘Lost Decade’ (2013-2022) entailed the dismantling of climate policy. Subsequently, the centre-left Labor government passed the Climate Change Act in 2022, Australia’s most ambitious climate policy shift in a decade. In this article, we address the interrelated questions of how to explain the changes in Australian politics that allowed for the Climate Change Act to be implemented and, by extension, what, if anything, changed between 2022 and 2024? We identify explanations for this shift in national policy across ideas, interests, and institutions as Australia increasingly engages in global competition for critical minerals The Australian case offers insights for other fossil fuel exporter economies, as even transformative policy remains constrained by entrenched political-economic structures. This mixed position enables Australia’s new ‘dual-track’ approach that entrenches both fossil fuels and green energy while its weak climate policy legacy renders Australia a policy and price ‘taker’ in the net-zero transition.

Electricity access statistics used to track progress against the Sustainable Development Goal 7.1 set by the United Nations have significant uncertainties, which may bring into question the electrification status of at least 87.2 million people in sub-Saharan Africa. Consequently, we call for a re-evaluation of the definitions of electricity access used by international organizations and the methodologies applied to calculate them.

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.

Sustainable lake restoration has been introduced recently as a strategy to address ecological, economic, and social challenges in nutrient management. The strategy would benefit at least 40 % of the world's lakes through addressing eutrophication, and the impact becomes even broader if we consider the complex nature of eutrophication (its linkage to multiple environmental problems). This approach involves: 1) demonstrating broader social and economic benefits, 2) integrating circular economies, and 3) directly engaging local communities in co-developing restoration goals, targets and monitoring. The current study explores opportunities to advance sustainable lake restoration using a well-established model that fosters interaction among restoration stakeholders. We assessed each model step for sustainability needs, identifying knowledge gaps and key factors for future success. We emphasize the need for a better understanding of the linkages between eutrophication and other environmental problems, proper monitoring programs to demonstrate broader restoration benefits, effective system analysis tools, sustainable nutrient recycling measures and accurate realization, and thorough documentation for life-cycle assessments. Achieving these goals requires significant policy and financing transformations, continuous engagement, and close collaboration among all stakeholders.

This paper aims to examine the sign, magnitude, and drivers of stock price reactions to corporate green bond announcements by U.S., Western European, and Chinese firms from 2013 to 2022. Using a standard event study methodology, we estimate abnormal stock returns around green bond announcement dates. Our analysis yields several novel findings. First, we document that green bond announcements were associated with neutral to positive abnormal returns during the market’s “inception stage” (2013–2018), but elicited negative reactions during the subsequent “growth stage” (2019–2022). Second, we show that this shift can be largely explained by changes in issuer characteristics that heighten greenwashing concerns. Specifically, growth-stage issuers exhibit a lower green innovation capacity and have fewer valuable growth opportunities relative to inception-stage issuers, potentially undermining investor confidence in the authenticity of their environmental motives. In contrast, changes in bond design, signaling value, pro-environmental investor preferences, or other issuer traits do not explain the downward trend in announcement returns. Our findings are robust to alternative specifications and do not apply to a comparable sample of non-green bond offerings. Overall, our results suggest that prospective issuers should carefully evaluate whether green bonds are appropriate for their firm, as investors are increasingly attuned to greenwashing risks. Our findings also point to a need for enhanced transparency and regulatory oversight to restore trust in the green bond market.