Redox flow batteries (RFBs) are a promising technology for stationary energy storage systems, particularly for intermittent renewable energy sources. It is critical to the growth of RFBs as a viable technology that development focuses on low-cost and more sustainable electrolytes based on cheaper, earth-abundant redox materials. One of the most important key components of a redox flow battery (RFB) is the electrode. The role of the electrodes is to ensure efficient electron charge transfer and to facilitate the reactions of the electrolyte redox couple on their surface. This requires, amongst others, large contact areas between the electrode and the electrolyte and electrocatalytic activation of the electrode to maximise power density for practical applications. In addition, the degree of compression of the electrode material has also been shown to improve the power density of the RFBs. The electrode/electrolyte interfaces are very specific for a particular electrolyte and a particular electrode material. Whereas the optimisation and performance enhancements have been previously investigated for vanadium-based electrolytes, so far, there are limited reports on tailoring and activating the electrode materials for all-iron electrolytes.
Project Description:
This PhD project aims to investigate and improve the electrode/electrolyte interface. The application of post-treatments of the carbon felts, using oxidative activation combined with surface-decoration with nano-electrocatalysts, is expected to yield significant improvements in the electrochemical reversibility and to lower activation overpotential, resulting in higher battery efficiency. The project aims to focus particularly on iron and vanadium-based electrolytes consisting of metal complexes with ligand systems that have so far not been investigated in terms of their electrode / electrolyte interactions. These chemically activated electrodes will be investigated using various in-situ, ex-situ and operando spectroscopic techniques (Raman, FTIR, XPS, EPR) to provide insight into the underlying activation mechanisms.
Work programme and objectives:
The effects of degree of compression and treatment of the electrode materials will be investigated to improve the electrode/electrolyte interface and increase the power density of the redox flow batteries. This studentship will aim to establish the relationship between degree of compression, porosity, and electrolyte transport, as well as investigating the relationship between electrode treatment, permeability, and electrolyte transport. Different compression rates and treatments (e.g., chemical treatments and/or thermal treatments) will be investigated using a combination of electrochemical impedance spectrometry (EIS) and load curve measurements applied at different states of charge. The electrode / electrolyte interface of treated electrodes and carbon felts will be investigated under operando conditions by using complementary in-situ and ex-situ spectroscopic techniques (specifically Raman spectroscopy) and transmission electron microscopy (TEM), scanning electron microscopy (SEM) and micro-computed tomography (CT) techniques in bespoke 3D-printed cells.
The PhD student will work in close collaboration with the industrial partner (Shell) and will have the possibility to spend up to 6 months at the Shell Technology Centre Amsterdam (STCA), Netherlands (funded). The student will work there closely with a team of international redox flow battery experts and will have access to Shell’s high-end, state-of-the-art energy and lab facilities. The PhD student will present and discuss progress in monthly meetings with the academic supervisory team and a team of energy storage experts from Shell. These meetings will provide additional technical feedback and an industrial perspective to the research.
The ideal candidate should enjoy working in a multi-disciplinary field of energy storage that ranges from materials to chemistry and phyiscs. Team-working qualities, clear communication skills and the ability to learn and develop new techniques are key for a successful candidate. Co-supervisors for this project are Prof Peter Nockemann (Chemistry) and Dr Miryam Arredondo-Arechavala (Physics).
International studentships, where available, will also cover tuition fees and include an equivalent maintenance stipend.
Further information: https://www.qub.ac.uk/courses/postgraduate-research/mechanical-engineering-phd.html#projects
Application deadline: 31st August 2023
Continue with Facebook
