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NEW ASPECTS OF THE STRUCTURE AND DYNAMICS IN NANOCRYSTALLINE OXIDESI. OVERVIEW OF THE PROJECTPropert

NEW ASPECTS OF THE STRUCTURE AND DYNAMICS IN NANOCRYSTALLINE OXIDES I.OVERVIEW OF THE PROJECT Properties of __terials can be drastically changed when one or more dimensions are in the nanometre regime. The resulting changes in chemical, physical and biological beh__iour, with exciting technological applications, has been of nanostructured __terials intense and growing interest over the last decade and anew research area, that of ,has emerged. nanotechnology Applications of these __terials, ,features in the forward scien__ planning of most developed countries (e.g. “the next industrial revolution” in Foresight plans of the UK, Japan and US) and the US gover__ent regards it as .This application is focused on one particular class of these novel __terials, namely nanocrystalline oxides, which are attracting special attention as advan__d __ramics, catalysts, sensors and adsorbents. These applications rely on the unique, but very poorly understood, structures and atomic transport mechani__s in nanocrystals. The aim of the project is to define the microstructure and measure atomic transport in selected __terials, and hen__ better understand the fundamental parameters and mechani__s, which govern these properties. The planned work will build on the expertise of the applicants, their suc__ssful EPSRC project (grant GR/K74876) in this area, and re__nt developments in the synthesis of such __terials. Key features of the proposal are the use of nanocrystals from different preparative routes and novel methods of restricting the grain growth. II.TRACK RECORD OF THE APPLICANTS The applicants firmly believe that it is the synergy of understanding the underlying chemistry and physics that underpins strong __terials technology in this country. They h__e specialised expertise in the various sophisticated methods and techniques involved in this proposal, and h__e well established reputations in the area of solid-state scien__. However, key to the suc__ss of this project will be the very strong research links that exist between the applicants (joint grants, postdoctoral fellows, postgraduate students and publications) that give the combined team aunique position in the study of defective __terials. The investigators h__e closely collaborated on combined stu___s of glasses [1,2] and, particularly relevant to the current project, sol-gel synthesis of nanocrystalline oxides [3,4]. The applicants were the investigators on 2- project GR/K74876 (rated 4), an investigation of Oion diffusion in technologically important nanocrystalline oxides. That project was extremely fruitful [4-7] and provided some of the foundations on which the current proposal is based. Alan V. Chadwick Professor of Physical Chemistry, University of Kent, __C (). Sin__ the 1970's his group has specialised in experimental stu___s of point defects and diffusion in solids, including ionic crystals, inert gas crystals and amorphous solids, with over 190 research papers. The __jor experimental techniques h__e been radiotra__r diffusion and electrical conductivity, with astrong emphasis on carefully prepared and characterised samples. The opening of the Dare__ury SRS led to the inclusion of X-ray absorption spectroscopy (XAFS) in the armoury of techniques __ailable to the group, and they h__e been amongst the pioneers in XAFS stu___s of defect structures in ionic __terials [8-10]. Re__ntly, atheme of the XAFS work of the group has been the nature of nanocrystalline oxides [e.g. 11-16] and played asignificant part in the formulation of the present proposal. Currently the group is involved in avariety of __terials-based projects of both academic and technological importan__ supported by gover__ent and industrial sour__s. In all cases the underlying goal is adetailed understanding of the defects and/or mechani__s of atomic migration and their role in chemical and physical pro__sses. Examples include gas-sensing __terials (EU-Interreg and Teaching Company projects), preparation of acousto-optic ionic crystals (CASE studentship with Hilger Crystals), ionic transport in polymer electrolytes (EPSRC studentship) and proton-conducting __ramics (EPSRC grant GR/L66212). The group has long-standing collaborations with other __terials groups in the UK and abroad, was amember of the ESF Nano Project and is part of acurrent EU Network of Ex__llen__ proposal for the development of lithium batteries. __rk E. __ith (Professor of Physics, University of Warwick, MES) .__rk __ith’s research programme over the last decade has been __ntred on the development and application of solid-state __R techniques to tackle questions from __terials scien__ and technology, condensed __tter physics and solid-state chemistry. The research is __ntred on using __R to improve the fundamental understanding of the local structure in awide range of __terials with an emphasis on 17 disordered inorganic __terials. This has included developing O, being the first to use this approach to detect nanoscale phase separation in sol-gel systems[17] (funded through GR/J23938). Work has also examined nanocrystalline oxides, detecting the presen__ of bulk, su_____ and defect oxygen sites in nanocrystalline MgO[4] (GR/K74876). Currently a __ntral theme of the research programme is to develop acomprehensive experimental methodology (with Prof. Newport, Kent) for disordered solids by combining __R with neutron and X-ray diffraction, vibrational spectroscopies and computer modelling of structure [20-24] (GR/L28647, GR/N64151 and GR/R59298). The standing of this work can be gauged by the number of on-going international collaborations that exist resulting in numerous publications in leading journals, and the group has re__ntly been designated a__rie Curie training site in “Solid State __R of Inorganic __terials”. One of these collaborations (with Prof. K.J.D. __cKenzie FRSNZ, IRL New Zealand) is of direct relevan__ to this proposal h__ing looked at mechanochemical activation of arange of __terials with __R. __R provides 1