Li and Na wetting of cathode ceramics
There is currently a large research effort in Oxford dedicated to developing a solid state lithium ion battery (SOLBAT) with significantly increased energy storage capacity compared with current designs. This DPhil project forms part of that effort, and is dedicated towards developing a deeper scientific understanding of the wetting behaviour of solid Li or Na on the cathode ceramic material. Ultimately, this will lead to more informed ways of optimising the cathode for best performance of a solid state battery.
In the early stages of the DPhil the student will be trained to be proficient in the use of advanced surface analysis equipment available to the SOLBAT project such as scanning electron microscopy (SEM), X-ray photoemission spectroscopy (XPS), and scanning tunneling microscopy (STM). Li and Na will be deposited in UHV and in other inert environments on doped single crystals of SrTiO3. This is a model conducting ceramic oxide where the surface structure is well known. Experiments will be carried out to establish the wetting behaviour of Li/Na on the atomic (STM) and microstructural (SEM) length scales, and also to investigate the reactivity of Li/Na with the substrate. Towards the end of the first year the student will use the hard X-ray XPS (HAXPES) facility in Manchester (SHR Institute) that has a penetration depth up 50 nm and will be able to provide information on the chemical environment of the buried Li/Na metal - oxide ceramic interfaces. Having performed some model experiments on a conducting SrTiO3 substrate the student will now face the challenge of working on insulating ceramic oxides used in Li / Na ion batteries such as LMO, LCO, NCA, and most relevant to the SOLBOT aims LLZO garnet. To be able to study these insulators with electron-based probes it will be necessary to prepare them in ultra-thin film form as epitaxial overlayers on a conducting substrate. This can be achieved either through UHV evaporation and oxidation of the elemental materials or via pulsed laser deposition of the target oxide. Having grown suitable thin films it will be possible to revert to the Li / Na wetting studies of year 1, but on technologically pertinent oxides.
Individual applications will be considered as and when they are received and this position will be filled as soon as possible.
Any questions concerning the project can be addressed to Professor Martin Castell ([Email Address Removed]). General enquiries on how to apply can be made by e mail to [Email Address Removed]. You must complete the standard Oxford University Application for Graduate Studies. Further information and an electronic copy of the application form can be found at http://www.ox.ac.uk/admissions/postgraduate_courses/apply/index.html.
This Faraday Institution-funded 4-year DPhil in Materials studentship will provide full fees and maintenance for a student with home fee status (this status includes an EU student who has spent the previous three years (or more) in the UK undertaking undergraduate study). The stipend will be at least £20,000 per year. Candidates with EU fee status are eligible for a fees-only award, but would have to provide funding for their living costs from another source such as personal funds or a scholarship. Information on fee status can be found at http://www.ox.ac.uk/admissions/graduate/fees-and-funding/fees-and-other-charges.