Nanomaterial-functionalised carbons for next-generation supercapacitor electrodes

To effectively utilise intermittent sustainable energy sources, and to reduce the current over-capacity in energy generation systems, necessary to meet 'peak demand', we must develop efficient energy storage technologies. Supercapacitors will play a key role in the future flexible energy grid (as well as in automotive and personal electronics), due to their ability to quickly charge/discharge (enabling high power output) and their potentially lengthy lifespans. However, current technologies suffer from low energy densities (~ 5 W h kg-1), meaning very large devices must be constructed if high energy capacity is required (e.g. in cars/busses). This deficiency is partially due to the materials from which the electrodes are constructed, commonly activated or porous carbons, which have low conductivity, low packing density, and poor inter-particle interconnectivity.

The materials I will develop in this Fellowship will provide elegant and practical solutions to these problems. I will, for the first time, scalably nano-texture the surfaces of bulk carbons (e.g. activated carbons) with nanomaterials, improving their conductivity and connectivity, as well as efficiently increasing their surface area and introducing highly active pseudocapacitive materials. This will dramatically improve the energy storage performance of these materials. I will achieve this through the utilisation of liquids containing charged nanomaterials that can be manipulated onto the carbon surfaces using highly scalable, low-cost methods such as electrodeposition. Importantly, the deposition strategies will negate detrimental nanomaterial re-stacking and agglomeration, thus harnessing the beneficial properties of individualised nanomaterials.

This cross-disciplinary work will bring together three departments at University College London (UCL). It will exploit the wide-ranging synthetic and analytical facilities in Dept. of Chemistry, the pioneering facilities for the creation of charged nanomaterial solutions in the Dept. of Physics & Astronomy and the world-class electrochemical manufacture and testing equipment in the Electrochemical Innovation Lab. This combination makes UCL the ideal location for this work. These facilities will allow both electrochemical- and chemical-deposition of charged nanomaterials to be developed in parallel and optimised for nano-structures including carbon nanotubes, graphene and MoS2. By controllably depositing these materials I will be able to control the surface morphology and redox-activity of surfaces, and therefore create materials which can be tuned. These will be extensively tested in lab-scale supercapacitor devices and the most successful will be scaled to produce an industrial demonstrator with my industry partner. Through careful structural investigation of the hybrid-materials, and the electrodes they produce, using advanced microscopy, phase-contrast X-ray tomography and small-angle X-ray scattering techniques, I will elucidate their structure-performance relationships.

This Fellowship will drive forward the industrial application of nanomaterials for energy applications by creating protocols by which they can be adhered onto a wide variety of surfaces, specifically targeting those for supercapacitor electrode materials. This will clearly have impact on UK manufacturers of supercapacitors, due to the improvements in capacitance, conductivity and energy density my advances will provide. This is especially applicable for my industrial partner (ZapGoCharger ltd.), who are keen to utilise my technological developments in their next-generation devices and exploit the inherent performance advances they will permit. More widely, my results will also have far reaching, multi-industry impact, for example, in the energy generation/storage sector more generally where a many applications require high surface area or redox-active electrodes e.g. fuel cells, batteries, and electrolysers. I will engage with these industries through my established academic and industrial connections. Overall this will mean it has the potential to influence the future of portable electronics, electric/fuel cell vehicles and grid-scale energy provision, which will concurrently produce real societal change. Additionally, the methods developed in this work will benefit a range of important industries (catalysis, composite materials, electrochemical sensors, anti-corrosion materials), as it will create high performance and durable materials that incorporate the multi-faceted benefits of advanced nanomaterials.

The potential economic impact of this work is highlighted by the fact that it encompasses two of the 'eight great technologies' (advanced materials and energy storage), which are areas the government believes can propel the UK to future growth and help it 'stay ahead in the global race'. The UK has a strong industrial position and skill base available to take full commercial advantage of the technological innovations I make. The result of successful commercialisation would be new job creation, financial rewards for those investing in the technology and societal improvements for the people of the UK and globally through the proliferation of sustainable energy provision. This economic impact will stem from my use-focused approach, developing methods and materials based on truly scalable processes and therefore providing an efficient road to technology transfer.

Further to its industrial and economic impact, I intend for this Fellowship to make an impact through my scheme of outreach and dissemination activities. For this I will develop interactive talks and demonstrations based on the science of energy storage, with the specific aim of interacting with school children across a range of ages. Teaching young people about methods for energy security and suitability is growing in importance as they will increasingly find themselves living in a 'low carbon' energy environment, which will utilise a wide range of different devices for energy generation and storage. It is my ambition to educate and inspire the next generation of scientists to help them solve the energy challenges we will all face in the future. I will also strive to engage the public more generally at science festivals and other events.

Thusly, this Fellowship has the potential to stimulate the economy, contribute to the drive for sustainable energy storage technologies and educate the community on why investment in these technologies is vital. These outcomes are highly achievable considering the wide-reaching scope of this work.