Size-selected Alloy Nanoparticles for Electrochemical Hydrogen Production
The production of hydrogen by electrochemical splitting of water offers a zero-carbon method for converting renewable energy to a fuel which can be stored for when it is needed and used to replace fossil fuels in many industrial processes. To produce hydrogen efficiently, electrocatalysts are needed that reduce the overpotentials for the hydrogen and oxygen evolution reactions (HER/OER) and thus avoid large amounts of energy being wasted. They must also remain stable over extended periods under the aggressive electrochemical conditions they typically operate under. The best performing electrocatalysts are based on Platinum and Iridium, whose scarcity and cost limits the large-scale deployment of electrochemical water splitting. There is thus a pressing need for the development of low-cost electrocatalysts that use lower loadings of these components or fully replace them with earth-abundant elements.
Multicomponent alloy nanoparticles are particularly promising as they offer high surface areas, and their catalytic performance can be tuned by both their size and composition. However, rational improvement of performance requires reliable deposition of nanoparticles with well-defined size and composition. This DPhil (PhD) project will use a newly acquired size-selected deposition source, that forms nanoparticles of controlled size by expanding a metal vapour through a nozzle, and then mass filters these to select only particles of a desired size. The formation of binary and ternary alloy particles will be studied and then their sizes and variation in composition characterised using electron microscopy, and X-ray photoelectron spectroscopy. The performance of optimised electrocatalysts will then be investigated for electrochemical water splitting. Advanced operando capabilities available in the group can then be used to probe changes to their electronic structure when in the electrochemical reaction environment. There are likely to be many opportunities to work at the nearby Diamond Light Source, the UK synchrotron, and to travel internationally to use other synchrotron facilities.
Any questions concerning the project can be addressed to Dr Robert Weatherup (robert.weatherup@materials.ox.ac.uk).
General enquiries on how to apply can be made by e mail to graduate.studies@materials.ox.ac.uk. 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 https://www.ox.ac.uk/admissions/graduate/applying-to-oxford.
