I have no open positions at present. However, if you are interested in working with me then I am always looking to support candidates in applying for personal post-doctoral fellowships (for instance see Newton International FellowshipsLink opens in a new window, UKRI postdoctoral FellowshipsLink opens in a new window, Royal Commission of 1851 FellowshipsLink opens in a new window, and Marie-Curie FellowshipsLink opens in a new window). If you are interested then please contact me with a CV plus small statement of your interests and we can discuss what would make a good proposal to develop and submit.
PhD projects starting in 2024
Imaging atomic-level electrochemistry in real-time using 2D material devices
Electrochemistry is the underpinning science that powers your mobile phone. And with the economies of scale the ubiquity of rechargeable lithium-ion batteries in mobiles brought, we have been able to expedite a rapid transition to an all-electric vehicle economy in the UK and many places around the world. While this illustrates the impact of what can be achieved with electrochemical technology, the need to fully decarbonise our economy demands that we realise further technologies across energy storage, chemical synthesis, and CO2 conversion.
The fundamental challenge is that electrochemistry is complex; with a myriad chemical and material processes occurring at buried solid-liquid interfaces that undergo continuous dynamic changes. This makes the informed design of new electrochemical technologies exceptionally difficult. New experimental techniques are required that can diagnose these processes in situ, that is capturing them as they occur in an operating environment.
We need a way to perform in situ atomic level imaging to answer these questions.
This PhD project will develop a new approach for capturing atomic level electrochemical processes in situ by fabricating special electrochemical cells from two-dimensional materials like graphene. These “micro-batteries” will be able to be operated and imaged directly inside a transmission electron microscope (TEM), yielding an atomic resolution imaging facility able to expose these atomic to nanoscale processes as they occur. This has yet to be achieved.
You will be joining a new multi-million pound research project at Warwick University –AIDEChem– to unlock this potentially groundbreaking capability. As well as the teams in electron microscopy, modelling, and nanomaterials in Physics, you will work with partners in Chemistry and WMG departments, as well as in Oxford and internationally.
If you enjoy condensed matter physics, materials science, materials chemistry, and have a passion for addressing the grand challenge of climate change by the application of science, then this is the project for you.
If you are interested in this project you can contact me at email@example.com.
Constructing an artificial interphase for zinc metal anodes through informed design
A longstanding challenge in rechargeable batteries has been to attain a practical metal anode, allowing for optimal energy densities and a good voltage window. But unfortunately the inherent reactivity of many battery chemistries, like lithium ion, mean that metal anodes would undergo prohibitive degradation. This is why modern Li-ion batteries use graphite as an anode host. The aqueous zinc battery has (re-)emerged as a prime candidate for realising the advantages of using a metal anode, as its relatively low reactivity bypasses some of the most serious problems with metals like lithium, with it even able to operate with a water-based electrolyte. Yet even these anodes still suffer from failures due to dendrite growth and hydrogen evolution.
Looking to the abundant research done on the lithium metal anode presents a potential solution; crafting a solid-electrolyte interphase (SEI) layer that coats the zinc anode in a protective skin, and thus limiting dendrite detachment and preventing side reactions while still permitting Zn ion cycling through it. We can achieve this by tailoring the electrolyte with the suitable inclusion of additives and co-solvents, engineering an SEI layer with optimal properties. Rather than doing this by trial-and-error, we instead want to do this by developing a fundamental understanding of the interlinking factors that lead to both; (i) the formation of a particular SEI, and (ii) the particular SEI enabling good cycling performance. This requires a comprehensive application of a broad suite of experimental characterisation techniques.
In this project, you will intentionally engineer interphase layers to achieve robust Zn metal anodes for rechargeable batteries. By combining advanced characterisation techniques, including transmission electron microscopy (TEM), mass spectrometry, X-ray absorption spectroscopy (XAS), mechanical indentation, and other methods, you will reveal the interlinking structural, chemical, and physical properties that enable a high performance zinc metal anode that is robust to repeated recharge cycles, and then use this knowledge to craft the ideal artificial SEI layer. You will get the opportunity to learn several sophisticated experimental techniques due to the extensive world-leading materials characterisation infrastructure available at Warwick University, and be able to collaborate with scientists at Oxford University and internationally.
This project is ideally suited to a student with a background and interest in the materials sciences, including physics, chemistry, materials science, chemical engineering, and related subjects. If you are interested contact me at.
Diagnosing the operation and degradation mechanisms in cathodes for rechargeable aqueous zinc batteries
Our transition to a decarbonised energy economy continues to demand new technologies to address the challenge of how we store energy. Major developments have been made in scaling the performance of rechargeable Li-ion batteries, all while making them more affordable, with the dividends now realised in a blossoming electric car industry. However, the need for energy storage at the electric grid level is forecasted to continue to grow rapidly, driven by the intermittency of renewables, where the high energy density yet high cost of Li-ion is not necessarily best suited.
There has been a recent revitalisation in the rechargeable Zn-ion battery in order to address this demand for an energy storage technology dedicated to stationary applications. Zn-ion offers significant advantages in terms of cost, recycling, supply chain security, and safety, all while still providing competitive energy density and lifespan.
Challenges remain however, including the problems of dendrite formation and corrosion at the metal anode, and unwanted reactions at the cathode. This project will focus on understanding these reactions at the cathode, nanostructured MnO2, and developing tailored electrolytes to suppress them. Achieving this goal will require diagnosing a set of intertwined parameters, including the structure of the cathode material and its interface, the changing pH of the electrolyte, the Zn-ion salvation structure, and others, many of which will evolve while the battery is cycled. Fortunately, at Warwick you will have access to one of the UK’s best equipped characterisation facilities, and will use a suite of advanced techniques to disentangle what leads to performance loss in Zn-ion cathodes. Operando X-ray absorption spectroscopy will grant insights into solvation structure and chemical reactions, in-situ X-ray diffraction and transmission electron microscopy will tell us about the structure changes, and nuclear magnetic resonance will inform us about the local pH and interfacial byproducts.
This project is suited to students with an interest and background spanning the broad remit of materials chemistry; including physics, chemistry, and materials science, and enjoys learning and mastering sophisticated experimental techniques. If you are interested contact me at.
Revealing the atomic-scale mechanisms for next-generation memory – the 2D ‘atomristor’
As we now approach the end of the road for the miniaturisation of conventional silicon devices, new “beyond Moore” device types are required to allow for continued advances in computing power. A core component of a computer is the memory, for which we ideally want a device that offers quick performance, high storage density, and non-volatility (i.e., it still ‘remembers’ when depowered). The need for such memories are even more necessary now, with emerging data-intensive applications from drug development to AI learning datasets.
The ‘atomristor’ is a memory based on the memristive switching of a 2D material, such as hexagonal boron nitride or molybdenum disulfide, and promises to offer all of the properties needed in an ideal memory component. Memristive switching is the reversible toggling between a high and a low resistance state, which can be used as a means of storing data. Unfortunately, the atomic level mechanisms behind this switching in 2D materials is only partly understood, with the interlinked role of atomic defects, the formation of the atomic ‘filament’, and how these all evolve over repeated cycles, still remaining unclear. To solve this we need to image a functional device at the atomic level while it is being operated.
This PhD project will use our state-of-the-art atomic resolution imaging facilities to expose these single-atom processes as they occur in working 2D material memristors, the understanding of which are crucial for us to realise these devices in practical applications. We will use transmission electron microscopy (TEM) to directly image these atomic transitions in real-time, and also use the electron beam to perform nanoscale tailoring of defects into the device structure to elucidate their role.
Alongside TEM imaging, you will fabricate these stacked 2D material devices in our semiconductor fabrication cleanroom, and in the process learn how to prepare and handle 2D materials. There are opportunities for you to engage with international collaborators with partners in the USA and Korea.
This project is suited to a student with interests in condensed matter physics, materials science, and nanotechnology. If you are interested in this project please contact me at firstname.lastname@example.org.