Synthesis and characterisation of organic electrodes for batteries.

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Anthropogenic activity is the primary contributor to the warming of the Earth's climate a substantial contributing factor is the burning of fossil fuels for energy production. The continued burning of fossil fuels will exacerbate the current problem and deepen the existing climate crisis. Global energy consumption is set to continue to increase in the future with several nations undergoing rapid growth. To offset climate change and meet forecasted energy demands renewable energy needs to position itself at the forefront of energy production. To facilitate this evolution in energy production, the weaknesses associated with renewables need to be mitigated; renewable energy sources are dynamic, and therefore peak production does not always correlate with peak demand. Via implementation of large-scale grid storage in the form of sodium-ion batteries, energy produced from renewable sources such as wind can be stored to meet peak demand. This is a singular example of the potential applications sodium-ion batteries offer. Sodium-ion batteries are not yet commercialised due to a lack of suitable anode material; however, sodium holds advantages over the current commercial battery system, lithium, sodium is cheaper, more abundant, and offers safety advantages in a battery system. To access the benefits of a sodium-ion battery system, a suitable anode material needs to be discovered. One category of anode materials for sodium-ion batteries that is currently relatively unexplored is organic anodes. Organic anodes potentially offer sustainable, renewable battery chemistry, however, understanding the processes that occur during charge and discharge are currently poorly understood. To facilitate the optimisation of existing organic anodes and aid the discovery of potential new organic anode materials a more comprehensive knowledge of the underlying mechanisms and processes that occur during cycling is required. By employing in-situ and operando techniques to current anode materials it is possible to achieve an enriched understanding of the processes occurring during cycling. In-Situ XRD can offer insight into phase formation and the relative amounts of each phase formed. In-situ Raman spectroscopy offers insight into changing local environments and bond formation. In-situ TEM can give an understanding of the phase separation during cycling and what particles are undergoing a phase change. Furthermore, in-situ resonant inelastic X-ray scattering (RIXS) can characterise the changing redox behaviour in a cell and can discover information the about electronic structure of a material. More operando and in-situ characterisation techniques exist and can be employed to discover further information on cycling behaviour. Data obtained from these methods can then be utilised to explain electrochemical results, offering the opportunity to optimise the performance of a material, as well as make theoretical predictions on the performance of potential organic battery materials.