Interdisciplinary Studies to Characterise and Optimise Novel Apatite-Type Fast-Ion Conductors

The proposed research will build upon previous success with a combined programme of experimental and computational studies of novel apatite-type ionic conductors, which are attracting considerable worldwide attention. Contrary to the traditional fluorite and perovskite-type oxide ion conductors, which conduct via a vacancy mechanism, the current evidence indicates that these apatite systems conduct via oxide interstitials, as first reported in our initial modelling study of the Si-based systems. This interdisciplinary project will extend our internationally leading research through new adventurous studies of novel Ge-containing apatite materials, which offer higher ionic conductivities, but have been less widely investigated. Evaluation of their true potential therefore requires immediate study. This powerful combination of materials synthesis and characterisation (at Surrey), NMR (Warwick) and computer modelling (Bath) will provide deeper insight into these exciting materials for potential technological applications (such as solid oxide fuel cells). Our considerable experience and past success in ion transport studies places us in a strong position to address key issues. In many instances, our project will be the first investigation of this type.