PhD Chemistry: Rapid materials synthesis probed in real time with neutrons

Environmental change and the depletion of fossil fuel reserves are two drivers for the development of materials for generating and storing energy. Yet energy-efficient methods to the synthesis of such materials are also crucial for realisation of sustainable energy scenarios. Using microwave (mw) radiation for materials synthesis has become well established over the last 10 years. However, a fundamental understanding of the interaction of mw fields with condensed matter and how chemical reactions subsequently occur remains to be developed. The only way in which such an understanding can be procured is via in situ characterisation techniques. In recent years we have used powder neutron diffraction (PND) ex situ to characterise the final and intermediate products of solid state mw reactions. More recently, we have designed equipment for mw-induced synthesis engineered specifically for use in situ with neutron diffraction.

This project will involve the design and performance of unique neutron diffraction-coupled microwave synthesis experiments, including:

• Optimisation of the existing mw reactor and development of a second generation SMC mw reactor. A high temperature mw cavity has been designed. The construction of the reactor, testing and commissioning will be performed. The apparatus presents us with the opportunity to investigate structure as a function of temperature and time, providing a thorough understanding of the synthesis process throughout its duration. The second generation instrument would not only allow us fluid control of applied power, but also enable us to operate at variable microwave frequency. Ultimately, this will be vital in the design of flow processing and for the prospects of scaled up manufacturing capability.

• Ultra-fast, energy-efficient synthesis and processing of functional and structural ceramics. We will investigate complex, high value ceramic systems including: (i) transition metal and main group binary nitrides (ii) superconducting complex carbides, borocarbides (using enriched B as required) and carbonitrides; (ii) carbide and nitride MAX phases. Neutrons will be crucial in probing the mechanisms of these rapid reactions By tuning the applied power and irradiation time, we aim to control product morphology from 1D and 2D nanomaterials (e.g. nanowires and so called “MX-enes”) to sintered powders and crystals.

• Rapid, energy-efficient synthesis of sustainable energy materials. Our recent work has shown that fast Li-ion conductors can be synthesised on minute timescales. We will progress this research to broaden our investigations to other fast ion conductors with an emphasis on electrode and electrolyte materials for Li-ion (with 7Li) and Na-ion batteries. Our equipment will also be used to synthesise narrow band gap thermoelectric (alloy) materials such as half-Heusler compounds and main group chalcogenides; in situ PND will allow us to probe the reaction mechanisms in these systems.

The project will be performed in collaboration with Dr Ron Smith at the Rutherford Appleton Laboratory and Dr Tim Drysdale, Open University.

Applicants should be UK or EU nationals with a First Class or Upper Second Class Honours degree or equivalent in Chemistry, Materials Science or related disciplines. The successful candidate will be highly self-motivated, be goal oriented and have good English writing and communication skills. An enthusiasm for innovation and speculative thinking is particularly encouraged. A master’s degree in a relevant subject would be advantageous but is not essential. The successful student would ideally begin study as soon as possible (May 2017).