Solid State & Materials Chemistry – High Temperature Superconductivity; Functional Materials: Structures and Electrical/Magnetic Properties of Mixed Metal Oxides, Oxide-Fluorides and Oxide-Oxyanion Phases; Electrolytes and Electrodes for Solid Oxide Fuel Cells; Materials derived from mineral structures.
Materials derived from mineral structures.
Current activity focuses on the signposts that naturally occurring minerals can offer for the synthesis of new materials with interesting properties. The synthesis and chemical control of new materials containing one-dimensional chains of cation polyhedra are being investigated. These studies are focusing particularly on the chemical aspects relating to magnetic order, electronic properties and possible cation charge order. We have successfully replicated the synthesis of mineral oxide sulphides with related chain structures and demonstrated the successful substitution of cations to provide new materials with unusual magnetic properties.
Electrolytes and Electrodes for Solid Oxide Fuel Cells
Current activity explores the possible enhancement of ionic conductivity in oxides via the introduction of oxyanion species into the structural framework. This has potentially important applications for both electrodes and electrolytes. Layered oxygen-deficient and oxygen excess Ruddlesden-Popper phases are also under investigation as possible electrode materials with high stability and high electronic and ionic conductivities.
The Greaves Group has a long-standing interest in the use of fluorine substitution and insertion to modify the properties of transition metal oxides. This work is continuing with the aim of clarifying the nature of unusual structural effects that occur in the resulting oxide fluoride phases