Walton Group Research Themes
Synthesis Methods for Inorganic Materials
We are developing solution mediated crystallisation routes for a wide variety of inorganic materials. This work makes use of a range of hydrothermal and solvothermal reactors in our laboratories: 100 - 500 oC, 20 - 250 mL. As well as detailed structural studies of the materials we prepare, we study formation mechanisms and kinetics using in situ diffraction with high energy X-rays (at the Diamond Light Source) and neutrons (at the ISIS facility): this allows us to follow crystallisation in real time while monitoring the evolution of atomic structure under reaction conditions with the aim of greater predictive ability in materials synthesis.Transition-Metal Oxide Materials
Our solution synthesis routes have allowed us to explore the chemistry of metal salts in solution, yielding families of new materials. For example, we have recently reported a range of new oxides of iridium and ruthenium with interesting magnetic properties and whose uses in electrocatalysis we are exploring. We have also uncovered solvothermal routes to various functional oxides, such as perovskites, pyrochlores and spinels, where crystallisation from solution offers control of crystal morphology from the nanoscale to the micron scale.Nanoporous Materials: Zeotypes and MOFs
We have a longstanding interest in porous inorganic solids and at present we are focussed on understanding the templating effect in phosphate zeotypes, in collaboration with solid-state NMR spectroscopists, who have developed new methods for examining structural motion, and on also the formation and properties of metal-organic frameworks (MOFs). Our group made the first in situ studies of MOF formation and we have built on this work to prepare new materials with porosity and reactivity suited to the capture of small molecules and in acid catalysis.
Applications of Materials; Catalysis, Devices and Interfaces
In collaboration with colleagues both at Warwick and in industry we have made use of our expertise in materials synthesis and X-ray characterisation to examine a number of systems of practical relevance. This has included the perovskite halides that are emerging as a new generation of photovoltaics in solar cells, moisture uptake by gypsum materials, and layered materials for coatings. We also are examining materials for heterogeneous catalysis of relevance to a number of industrial applications, including automotive exhaust catalytic converters and electrocatalysis in fuel cells.