AVS 49th International Symposium
    Biomaterials Wednesday Sessions
       Session BI+AS-WeM

Paper BI+AS-WeM3
Surface Chemistry of Environmentally Relevant Transition Metal Oxides Studied in Aqueous Solutions using Soft X-ray Spectromicroscopy

Wednesday, November 6, 2002, 9:00 am, Room C-201

Session: Ambient Surface Science Techniques
Presenter: B.P. Tonner, University of Central Florida
Authors: B.P. Tonner, University of Central Florida
K. Pecher, University of Central Florida
Correspondent: Click to Email
The surface chemistry of environmentally relevant inorganic oxides can now be reliably assessed in solution, with high spatial resolution, using a methodology based on x-ray absorption spectroscopy with microfocussing.@footnote 1,2@ A crucial aspect of this research is that the studies are performed in the presence of a complete water layer, with control of parameters such as buffer concentrations, dissolved oxygen content, and pH. We have concentrated on the fate of Fe and Mn oxides in mineral model compounds, and in addition important nano-scale materials like the 'green rusts.' Spatial chemical inhomogeneities are prevalent in such nano-scale minerals, and are revealed by x-ray spectro-microscopy "chemical state mapping." The state of these studies has matured to the point where chemical intermediates, formed as a result of microbial metabolism, can be reliably detected and identified. This paper will emphasize the quantitative aspects of performing assays of surface transition metal oxide valence distributions using L-edge spectromicroscopy. @FootnoteText@ @footnote 1@ Rothe, J., E.M. Kneedler, K.H. Pecher, B.P. Tonner, K.H. Nealson, T. Grundl, W. Meyer-Ilse, and T. Warwick, Journal of Synchrotron Radiation 6, 359-361 (1999).@footnote 2@ K. Pecher, E. Kneedler, J. Rothe, G. Meigs, T. Warwick, K. Nealson, and B. P. Tonner, X-ray Microscopy 1999, W. Meyer-Ilse, T. Warwick, and D. Attwood, ed., (American Institute of Physics, NY, 2000) p. 291-300.