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Climate change has been widely recognised as one of the most urgent and growing threats to natural and cultural heritage in the twenty-first century, and the indelible impact of humanity has led to the definition of a new geological epoch, the Anthropocene. Indigenous peoples are disproportionately affected by natural and human-induced changes to the environment. Their vulnerability is exacerbated by centuries of cultural and territorial disenfranchisement within settler-colonial nations. This dissertation aims at understanding Indigenous perceptions of heritage in the face of climate change and its intersection with the impacts of settler- colonialism. It analyses how these on-the-ground perceptions can, in turn, inform heritage organisations and contribute to safeguarding the many facets of tangible and intangible Indigenous heritage for future generations in the Anthropocene. This is accomplished through a comparative, transnational case study of two communities each from the Dehcho First Nations in the Northwest Territories, Canada, and the Aymara and Quechua peoples in northern Chile. I use a multi-method approach consisting of semi-structured interviews, oral histories and participant observation. The data is complemented by environmental and heritage legislation and grey literature at multiple organisational scales for both case studies. Three lines of enquiry are explored through an applied comparative thematic analysis: i) the perceptions of climate change and associated land loss/change among Indigenous groups and how this impacts each group’s notions of challenges to its cultural identity; ii) the intersection of the effects of post- colonialism, ongoing industrial activities and climate change on the intergenerational transmission of ancestral knowledge and notions of place attachment; and iii) how international, national and regional political and sociocultural rhetoric on environmental and heritage conservation affect local, grassroots considerations for safeguarding heritage. The similarities and contrasts of the Dehcho First Nations, Aymara and Quechua experiences of climate change across the North-South divide are related from the grassroots to arrive at redefining heritage practices in the Anthropocene. The results demonstrate that decolonising heritage is not only necessary, but that this decolonisation depends on building and actively engaging in intercultural empathy through the global threat of climate change. In order to understand how Indigenous practices, places, and items are valorised—attributed value—as heritage in the face of climate change, one must empathise with the cultural loss that exists in the temporal and cognitive spaces between Indigenous individuals’ moments of nostalgic reference and today.

This perspective covers the use of molybdenum disulfide and related compounds, generally termed MoSx, as electro- or photoelectrocatalysts for the hydrogen evolution reaction (HER). State of the art solutions as well as the most illustrative results from the extensive electro- and photoelectrocatalytic literature are given. The research strategies currently employed in the field are outlined and future challenges pointed out. We suggest that the key to optimising the HER activity of MoS2 is divided into (1) increasing the catalytic activity of the active site, (2) increasing the number of active sites of the catalyst, and (3) improving the electrical contact to these sites. These postulations are substantiated by examples from the existing literature and some new results. To demonstrate the electrocatalytic properties of a highly conductive MoS2 hybrid material, we present the HER activity data for multi-wall MoS2 nanotubes on multi-wall carbon nanotubes (MWMoS2@MWCNTs). This exemplifies the typical data collected for the electrochemical HER. In addition, it demonstrates that the origin of the activity is closely related to the amount of edges in the layered MoS2. The photoelectrocatalytic HER is also discussed, based on examples from literature, with an emphasis on the use of MoSx as either (1) the co-catalyst providing the HER activity for a semiconductor, e.g. Mo3S+4on Si or (2) MoS2 as the semiconductor with an intrinsic HER activity. Finally, suggestions for future catalyst designs are given.

An amorphous WO3 induced lattice distortion strategy leads to only 2 wt% Ir for efficient overall water splitting in acid.

Achievement of sustainable development in light of ongoing climate change and biodiversity pressures benefits from the deployment of innovations that foster engagement and uptake across all levels, mobilises finance flows commencement to the scale of the challenge, and enables the dissemination of transition solutions that support the low carbon economy. This research investigates the relationship between the legal architecture of market mechanisms under international law and the role of private actors, and how this contributes to sustainable development. Through an exploration of how market mechanisms under the climate change and biodiversity regimes have achieved environmentally sound outcomes, been advanced in sectoral approaches, and facilitated via bilateral and multilateral trade and investment relationships, important insights are identified regarding the composition of effective law and governance architectural approaches. Leveraging experiences derived from treaty practice viewed through an interactional account of international law, this assessment elucidates the important role played by alignment of legal regimes, robust transparency measures, and complementary schemes such as stakeholder-endorsed certifications in buttressing the established measures to ensure sustainable development outcomes and contributes to understanding the role of private actors in the operationalisation of environmental agreements. Research findings suggest it is the interaction of norms across the international legal architecture, informed by relationships within and across relevant treaty systems and the general corpus of international law, and actualised through engagement with private actors as a component of market mechanisms that provides the opportunity for congruence of practice, forging of shared understandings, and normative internalisation and ownership among communities of practice that stimulates both innovative solutions and ambitious action.

Halide perovskites are the leading candidates for next-generation, low-cost optoelectronics with power conversion efficiencies well above 25%. However, operational stability remains a key challenge. Although there is an understanding that the microscale and nanoscale play a consequential role in determining the macroscopic performance and stability, significant gaps remain in the mechanistic understanding of degradation processes at the nanoscale and the mechanisms for stability in cation-alloyed systems. Nanoscale hexagonal phase impurities have been identified as problematic for operational stability, leading to both performance losses and morphological degradation. However, it is still unclear at what stage these phase impurities originate. Understanding this better is critical in order to mitigate the harmful effects of these phase impurities on performance and operational stability. Cation alloying is a commonly used technique in the field to mitigate these hexagonal phase impurities, although not without its challenges. In this thesis study, the nanoscale structural landscape of key halide perovskite compositions is studied. By taking snapshots of the perovskite at different states of the annealing process, the impact of phase impurities on device performance is characterised. Thereon, the mechanism by which composition dictates photostability in FA-rich perovskite absorber layers is studied. It is demonstrated that the composition impacts the degree of octahedral tilt, which is essential to restricting the transition to hexagonal phase impurities. Additionally, it is demonstrated that while a judicious mix of A-site cations can be used to stabilise the photoactive black phase of halide perovskites, it is challenging to achieve this homogeneously over large areas, necessitating a search for alternative or complementary approaches to stabilise perovskite via octahedral tilt. Using scanning electron diffraction (SED) studies, the spacegroup of additive-stabilised-CsPbI3 is demonstrated to be a low symmetry tilted γ-phase. Furthermore, using SED, the nanoscale structural landscape of mixed-phase CsPbI3 absorber layers is studied and it is demonstrated that both narrow-bandgap γ-phase and wide-bandgap δ-phase co-exist at the nanoscale, enabling stable and bright white-light emission. Overall, this thesis provides insights into the role of nanoscale structure in dictating the properties and behaviour of halide perovskites and offers rational guidelines for their optimisation and use in optoelectronic devices. Additionally, it is demonstrated that SED is a powerful tool for studying these materials at the atomic scale, allowing for the detailed characterisation of their structures and properties.

Self-organizing nanopatterns can enable economically competitive, industrially applicable light-harvesting platforms for thin-film solar cells. In this work, we present transparent solar cell substrates having quasiperiodic uniaxial nanowrinkle patterns with high optical haze values. The self-organized nanowrinkle template is created by controlled heat-shrinking of metal-deposited pre-stretched polystyrene sheets. A scalable UV nanoimprinting method is used to transfer the nanopatterns to glass substrates on which single-junction hydrogenated amorphous silicon p-i-n solar cells are subsequently fabricated. The structural and optical analyses of the solar cell show that the nanowrinkle pattern is replicated throughout the solar cell structure leading to enhanced absorption of light. The efficient broadband light-trapping in the nanowrinkle solar cells results in very high 18.2 mA/cm2 short-circuit current density and 9.5% energy-conversion efficiency, which respectively are 35.8% and 39.7% higher than the values obtained in flat-substrate solar cells. The cost- and time-efficient technique introduces a promising new approach to customizable light-management strategies in thin-film solar cells.

This study provides the first comprehensive overview of the sustainability performance of the hotel sector in the Himalayan region: Sagarmatha National Park and Buffer Zone, using both environmental, economic, and technical criteria. In particular, the performance of 45 buildings in this region were measured and quantified in terms of life cycle based carbon footprint, life cycle costs, heat loss rate, number of guests, energy consumption, and area. Buildings were classified into three types: traditional, semi-modern and modern. The statistical analysis included testing for significant differences between such categories by means of ANOVA, and determination of the correlation between the same parameters. Results show a significant difference between the buildings’ total carbon footprint and operation stage carbon footprint while, there is no significant difference between the buildings’ life cycle costs. Traditional buildings have on average the largest carbon footprint and life-cycle cost over the typical building lifespan of 50 years of building lifespan. The ANOVA tests highlight how heat loss rate, size of the building and number of tourists in the hotels are significantly different across the building types. A strong positive correlation is observed between environmental impact, economic impact and energy consumption for the household activities, and a negative correlation with the number of guests and building size. By considering several buildings, this study allows to draw new and more general conclusions about effective sustainability strategies in the whole hotel sector in the Himalayan region. In particular, it shows that reducing impacts in the operation stage should be highly prioritized, focusing on reducing energy consumption and heat loss and shifting to the use of renewable energy sources.

Formate production via both CO2 reduction and cellulose oxidation in a solar-driven process is achieved by a semiartificial biohybrid photocatalyst consisting of immobilized formate dehydrogenase on titanium dioxide (TiO2|FDH) producing up to 1.16±0.04 mmolformate gTiO2-1 in 24 hours. Isotopic labelling experiments with 13C-labelled substrates support the mechanism of stoichiometric formate formation through both redox half-reactions. TiO2|FDH was further immobilized on hollow glass microspheres to perform more practical floating photoreforming allowing vertical solar light illumination with optimal light exposure of the photocatalyst to real sunlight. Enzymatic cellulose depolymerization coupled to the floating photoreforming catalyst generates 0.36±0.04 mmolformate mirr-2 after 24 h. This work thus presents simultaneous solar-driven valorization of waste streams, demonstrates the advantages of biohybrid photocatalysts in photoreforming for the first time and will provide inspiration for the development of future semi-artificial waste-to-chemical conversion strategies.

To meet the increasing demand for sustainable products, one can look to nature to scout new functional materials. For instance, the most brilliant and striking colours in plants are obtained using cellulose nanofibrils organised in helicoidal architectures. Interestingly, similar helicoidal architectures with analogous optical response can be obtained in vitro by self-assembly of cellulose nanocrystals (CNCs). CNCs are rod-like colloids capable of arranging into a liquid crystalline phase above a critical concentration in suspension. So far, the process that governs the self-assembly of CNCs into photonic structures was studied only at small scale. This neglects the limitations and challenges posed by large-scale and continuous processes which are prevalent in industrial contexts. In this thesis, I demonstrate how the self-assembly of CNCs can be precisely controlled to produce meters-long films using a roll-to-roll (R2R) equipment. Starting with commercially available material, the preparation of CNC suspension was optimised for R2R deposition to produce films with vibrant photonic colour across the visible range. Particularly, I discuss how the suspension properties, the casting parameters and drying time relate to the optical properties of the produced films. To validate the use of such materials for pigment preparation, I develop a protocol to produce a series of coloured microparticles from R2R-cast CNC films. The optical properties of the CNC microparticles were then assessed in various environment and finally benchmarked against other commercial effect pigments and glitters.