Smiley, R.J., and W.N. Delgass, "AFM, SEM, and XPS Characterization of PAN-Based Carbon Fibers Etched in Oxygen Plasmas," J. Mater. Sci., 28, 3601-3611 (1993).

Eshelman, L.M. and W.N. Delgass, "Acetonitrile Synthesis over Potassium-Promoted, Supported Iron Catalysists," Catalysis Today, 21, 229-242 (1994).

Adams, R.C., L. Xu, K Moller, T. Bein, and W.N. Delgass, "Zeolite Encapsulated Vanadium Oxo Species for the Selective Catalytic Reduction of NO by NH3," Catalysis Today, in press.

Professor Delgass' interest in coatings is focused on chemical bonding at the coating/substrate interface, the effects of aging on the chemistry of thin coatings and effects of substrate topography of coating adhesion. Four analytical tools are used in this work. X-Ray photoelectron spectroscopy (XPS) gives composition and oxidation state information from a surface layer about 10 nanometers thick. This tool has been used to follow oxidation aluminum alloy surfaces caused by processing and the functionalization of carbon fiber surfaces in preparation for use in carbon fiber composites. Fourier transform infrared spectroscopy (FTIR) reveals the presence of functional groups by their vibrational signature and thus is used to follow surface chemical interactions, and along with nuclear magnetic resonance (NMR), can be used for detailed chemical characterization of thin coating films. Scanning force microscopy (SFM) is an ultrasensitive profilometer that measures surface roughness on the 10 to 1000 nanometer scale and has been used to assess effects of pretreatment on the roughness of carbon fibers. The chemical and physical characterization of interfaces and thin solid layers near interfaces provided by these tools allows study of coating adhesion and adhesion failure mechanisms as well as chemical changes in the selvedge region caused by diffusion or chemical degradation near the interface.

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