Sustainable Electrodes for Advanced Flow Batteries

The research programme proposed in this Fellowship application details a plan to develop alternative electrodes for RFBs using sustainable resources. RFBs often employ carbon felts as electrodes, prepared from non-sustainable polyacrylonitrile (PAN), and their activity towards the redox reactions is poor, leading to low efficiency systems. I propose to use electrospinning, a very versatile processing technique that allows for fine control of the features of the materials prepared, to produce a new generation of freestanding electrodes with unique tailored properties that will increase the power density and voltage efficiency of RFBs.

Bacterial Nanocellulose for Energy Applications

Our project aims to reuse the leftover of the fique natural fiber production (juice) from local producers in Antioquia, where close to 100 farmers of fique fibers sell this raw material at a price of $150 COP/kg for the production of sacks and cord. We will use the fique juice as a culture medium for the Komagataeibacter Medellinensis bacteria for the synthesis of bacterial nanocellulose, which will be further activated for energy storage applications, including lithium-ion batteries and supercapacitors. With this project, we will support local farmers, who will benefit from selling their agricultural waste to biomass companies, providing farmers a new source of income. The proposed collaboration involves Universidad Pontificia Bolivariana (UPB) and Queen Mary University of London (QMUL).

3D printed electrodes for energy conversion and storage technologies

Here I propose to use 3D printing to explore new electrode composites consisting of nanostructured graphene / transition metal electrocatalytic species for application in energy storage and conversion technologies. This research will lead to the development of a variety of electroactive composites, with different geometries and microstructures, and high electrocatalytic performance for batteries, fuel cells and water electrolyser systems. This research has the potential to truly transform the field of electrode design and expand the use of 3D printing techniques for the processing of new electrocatalytic architectures.

Testing of a Freestanding Oxygen Bifunctional Electrocatalyst for Alkaline Regenerative Fuel Cell Ap

This is a collaborative project with the University of Copenhagen and Dr Maria Escudero-Escribano to conduct electrochemical measurements in freestanding electrodes prepared by PhD student Linh Tran Ngoc, consisting of NiFeOx /C electrospun fibres, using their Gas Diffusion Electrode set up .

Bifunctional Hybrid Electrocatalysts

The high cost of the noble metal catalysts employed in energy devices is one of the major drawbacks to their full development and exploitation. There are many reports new materials that can overcome state-of-the-art limitations. However, not much research has been done to understand the structure-property relationships to allow an improved performance. This project aims to create transition metal perovskite/nitrogen-doped carbon electrospun nanofibres as alternative cost-efficient bifunctional electrocatalysts to replace noble metals in energy conversion and storage devices. At the same time, we will develop new in situ studies that will allow a deeper understanding of the structure-property relationships allowing for further optimisation.

Development of a new class of adaptable self-supporting hydroxide-ion conducting membranes

We are making self-supporting membranes based on MOF nanofibres, which have a high intrinsic hydroxide ion conductivity.

Sustainable Redox Flow Batteries, EPSRC and the Centre of Advanced Materials for Integrated Energy Systems (CAM-IES) (in collaboration with UCL).

Redox flow batteries represent a remarkable low cost alternative for grid-scale energy storage. They often employ carbon felts as the electrodes, but the activity towards the redox reactions are often poor, leading to low operating power densities. Additionally, the complex flow characteristics of the electrodes are often not well understood. This project aims to synthesise novel electrode structures from sustainable carbon sources via electrospinning, which will allow control of physical characteristics such as porosity, surface area and fibre size, but also to incorporate chemical species that help enhance the kinetics of the redox processes. Advanced x-ray imaging will provide a unique insight into the microstructural properties of the electrodes, and electrochemical testing in a full flow battery system will help identify new materials that will lead to improved flow battery performance and durability.

Understanding Interactions between Vanadium Ions and Carbon Electrodes using the Electrochemical Quartz Crystal Microbalance

Redox Flow Batteries RFBs represent one class of electrochemical energy storage devices in which the energy is stored using chemical reduction and oxidation processes. Here we use the electrochemical quartz microbalance (EQCM) to explore the reaction mechanisms between vanadium species and electrospun carbon-based electrodes. This is a pioneering study on using EQCM technique for the first time to understand the interactions electrode surface and redox-active species in redox flow cells. Understanding the redox processes in flow batteries and interaction electrode –active species is key to accelerate the development of this technology.

PhD studentship collaboration industry

Use of quantum dots to improve the performance of photo-anodes in solar conversion devices

Synthesis and use of QDs to improve the performance of photoanodes in solar conversion devices, i.e. photo-fuel cells, photoelectrochemical cells. PhD student: Han Meng

Sustainable Processing of Energy Materials from Waste

This project aims at developing new processes for waste remanufacturing based on hydrothermal and microwave treatments to yield sustainable products such as advanced carbon materials and chemicals, which in turn could be manufactured into battery devices Hydrothermal or microwave conversion of waste will result in a liquid phase containing important chemicals such as levulinic acid (LA) and 5-hydroxymethyl furfural (5-HMF), which are platform intermediates for a range of products including solvents and precursors of polymers, pharmaceuticals, plasticizers and other biofuels. We will separate these chemicals from the aqueous phase using preparative chromatography and convert them into other useful products using the carbon catalysts produced from the solid phase of the waste conversion. This will thus close the loop in biowaste product utilization. In parallel, we will also use the solid carbon materials to manufacture anode materials for Li and Na ion batteries. We will test the performance of these waste-derived electrodes in half- and, based on the best performant materials, full cells. We will evaluate the environmental impact of the manufacturing of these products at each life cycle, their cost compared with other products on the market, and we will perform multiscale modelling to predict the ability of these processes and products to be upscaled. Our proposed collaborative research activities have the potential to reduce environmental pollution and find new and innovative ways to recycle/remanufacture waste into advanced materials. In addition, the resulting biofuels and batteries from our processes will help the UK achieve its targets to reduce greenhouse gas emissions and introduce more renewables. A team of highly qualified researchers has been brought together for this project, including two top research institutions in the UK (QMUL and UCL) and two in China (Tsinghua and Chinese Academic of Science) and researchers with complementary expertise in hydrothermal and microwave manufacturing, heterogeneous catalysis, biowaste conversion, carbon materials and battery research. This project will train two PDRAs and two PhD students in the UK which will interact closely with two PDRAs in China. This grant will ensure the continuation of long lasting collaborations between the UK and China, will help prevent pollution and waste in both countries, and develop sustainable technologies for manufacturing advanced carbons, chemicals and batteries.

Feasibility of biomass-waste derived porous electrodes in advanced redox flow batteries - (The Royal Society International Exchanges, in collaboration with MIT)

Escalating greenhouse gas emissions and associated climate volatility represents an existential threat to humanity. Deep and rapid decarbonization of the global energy systems requires the wholesale replacement of fossil fuels with renewable resources (e.g., wind, solar). However, these resources are intermittent and unpredictable challenging the existing grid infrastructure which is based on the just-in-time dispatchable generation enabled by combustion of fossil fuels. As such, flexible energy management systems, including electrochemical energy storage technologies, are urgently required to enable reliable electricity delivery from the variable assets. Among them, redox flow batteries (RFBs) are excellent candidates for large-scale, long duration energy storage due to their flexible design, long service life, high reliability, and environmental friendliness. Nevertheless, this technology is still in its infancy in terms of optimisation of materials and battery design that can lead to improvement in performance and cost. This proposal seeks to improve upon one of their performance-determining components: the electrodes. We will use electrospinning to synthesise sustainable new materials, replacing current fossil-fuel-derived carbon electrodes with electrodes generated from biomass-waste. Electrospinning is a versatile technique that allows the production of freestanding fibrous materials. An additional part of the project will focus on the analysis of viability and economic aspects of using biomass-waste to produce RFB electrodes, while also enabling a finer control of their property sets, through a combination of modelling and experiment, to enhance technical performance and durability.

Bifunctional electrocatalysts for oxygen evolution and reduction reactions

EPSRC First Grant EP/P031323/1 The search for green alternative sources of energy is of great importance for our current society. In order to battle increasing greenhouse gases and global warming created by the use of fossil fuels, and to meet the UK's 2050 climate change targets, we need to develop new technologies that allow researchers to tackle this problem. This project aims to create transition metal perovskite/Nitrogen-doped Carbon electrospun nanofibres as alternative cost-efficient bifunctional electrocatalysts to replace noble metals for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in energy conversion (PEM fuel cells and water electrolysers) and storage (metal-air batteries) devices. At the same time, I will develop new in situ studies that will allow a deeper understanding of the structure-property relationships allowing for further optimisation.

Bifunctional electrocatalysts for OER and ORR prepared by electrospinning

Design and synthesis of new transition metal oxide perovskites/ N-doped C for OER and ORR catalysis using electrospinning PhD student: Gulnara Naghiyeva