Condensed matter neutron science down-under: From magnetic cobaltates to polymer substrates for biosensing applications
- Event time: 1:00pm
- Event date: 31st October 2005
- Speaker: Michael James (Bragg Institute Sydney)
- Location: Room 2511, James Clerk Maxwell Building (JCMB) James Clerk Maxwell Building Peter Guthrie Tait Road Edinburgh EH9 3FD GB
Condensed matter research at the Bragg Institute is based around neutron and X-ray scattering, and ranges from physics studies of magnetism and ferroelectrics to biological investigations of biomimetic cell membranes. I will present results from a series of studies by members of the Institute. Rare earth perovskite cobaltates have generated much interest as cathode materials for solid oxide fuel cells, as high temperature membranes for oxygen separation and due to their diverse range of electrical and magnetic properties. We have synthesised a wide range of these cobaltates (Ln1-xSrxCoO3-d) (Ln = Y3+, lanthanide ion), and found a series rich with different structure types as a function of rare earth ionic radii and Sr2+ doping level. Magnetic and electrical properties were found to depend critically on cation and oxygen vacancy ordering. Plasma polymer coatings adhere to and contour the surfaces of most organic and inorganic materials, and are attractive as surface chemical modification systems, since they offer both robustness and inherent surface chemical functionality for further surface chemical derivatisation. Allylamine and hexamethyldisiloxane plasma polymer coatings were prepared on silicon wafers, and analysed using AFM, XPS, X-ray and neutron reflectometry. The latter technique allowed the quantification of labile protrons as well as the hydration of these polymer films.
This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..