The redox chemistry and the changes that occurred within the solids were studied for an excessively exchanged and a nearly stoichiometric CoZSM-5 zeolite as a function of pretreatment, reduction, and reoxidation conditions. Both gravimetric and volumetric techniques were used to determine this chemistry and the stoichiometry of the processes, which became reversible after the first couple of oxidation/reduction cycles. The catalyst was examined in its several states by diffuse reflectance spectroscopy (DRS), X-ray diffraction (XRD), X-ray photoelectron spectroscoy (XPS), and both the Faraday and Gouy magnetic susceptibility methods. With the excessively exchanged sample, it was found that Co 3 O 4 formed after pretreatment with O 2 and that Co metal was produced on reduction with either CO or H 2 at 773 K in amounts corresponding to only a portion of the Co 2+ originally present. The stoichiometric sample showed evidence for the presence of Co 3+ , but crystalline Co 3 O 4 was not detectable. However, two different products were formed from the original freshly exchanged (and hydrated) zeolite, depending upon whether it was dried in an inert gas or in O 2 as the temperature was raised to 773 K.

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Recent work in our laboratories has fully characterized the surface region of a segmented poly(ether‐urethane) (PEU) extending from the air/polymer interfacial region through bulk depths in the micron range. This characterization utilized energy and angle dependent Electron Spectroscopy for Chemical Analysis (ESCA), Attenuated Total Reflectance–Fourier Transform Infrared Spectroscopy (ATR–FTIR), and Comprehensive Wettability Profiling (contact angle using a homologous series of liquids) as defined by Zisman. In this study this same multi‐analytical‐technique approach is used to elucidate changes in these PEU surfaces induced through an H2O Radio Frequency Glow Discharge (RFGD) plasma. This investigation reports both qualitative and quantitative changes due to the modification treatments as well as the permanency of the changes effected on these surfaces through the plasma treatment. From our analyses, the amount of surface residing polyurethane (hard segment) is observed to increase due to a proposed plasma etching mechanism. Further, the addition of oxygen containing functionality is detected at the modified surfaces unique with respect to the unmodified PEU. These surface modifications which show large increases in wettability, are finally observed to be semi‐permanent over a time period of 6 months.

Ion scattering spectroscopy (ISS) and x-ray photoelectron spectroscopy (XPS, ESCA) were used to study the dispersion of the vanadium phase and the coverage of Al,O, by vanadium. A series of V/AI,O, catalysts was prepared by equilibrium adsorption with vanadium loadings varying from 1.9 to 6.7 wt.% V. By monitoring the ISS AI/O intensity ratio the surface coverage of the catalysts was determined. The surface coverage increases from 15 to 33% with increasing the loading from 1.9 to 3.5 wt.% V. The results are consistent with a model of a uniform monolayer vanadium phase. For higher vanadium loadings the surface coverage appears to level off, suggesting the formation of a multilayer vanadium phase.