The surfaces of catalyst nanoparticles and their interaction with their support dictate their activity and selectivity. A lot of information on organic molecule - nanoparticle-support interaction is ad-hoc and based on mechanisms obtained using indirect averaging techniques. This makes it difficult to get an idea of variation and thus optimise the properties of the catalyst materials. Scanning transmission electron microscopes allow high-resolution imaging and spectroscopy to investigate localised bonding within materials.

This investigation will focus on catalyst particles developed by Johnson Matthey for use in fuel cells. Fuel cells are a viable low-carbon transport solution and optimising the fuel cell design is a crucial part of making this a main-stream technology. The performance of the cathode catalyst is one of the barriers to the further development and understanding the interaction of these particles with oxygen, using the combination of spectroscopy and density functional theory modelling, is the first aim of this project. This work will use the new Johnson Matthey electron microscopy facilities based at Harwell which were opened earlier this year, as well as the facilities based at Oxford Materials. The information obtained about the catalyst particles will be able to be fed straight into the catalyst design process at Johnson Matthey.

In 2015, the UK SuperSTEM facility received one of a new generation of microscopes which make it possible to do spectroscopy with a 10-fold increase in energy resolution. This increase in energy resolution makes it possible to obtain information on phonon resonances within the material. The second aim of this project will be to use this cutting-edge technology, subject to availability, to investigate the possibility of obtaining crucial information about the functional groups at the surface of the catalyst particles.

This project is aligned with the EPSRC research themes of Energy and Manufacturing the Future. The EPSRC leads the RCUK cross-council theme of Energy. One to the aims is to strengthen areas with the potential to help the UK meet the 2050 climate change targets (reducing greenhouse gas emissions by at least 80% relative to 1990 levels). The UK government plan (The Carbon Plan: Delivering our low carbon future, Department of Energy and Climate Change) sets out several pathways to achieving these targets including low carbon transport. Fuel cells provide a viable low carbon transport solution which could significantly contribute towards the UK meeting the 2050 emission target. Fuel cell technology is also a way of securing the energy supply, which is one of the RCUK priorities for the future. This work on catalyst particles for fuel cells also has the potential to impact on other catalyst research areas, linking with the Manufacturing the Future research theme. In addition, catalysis itself is one of the research areas that has been ear-marked for growth by the EPSRC.