Iron foil surface preparation

The above ideas that anion-cation pair sites are the surface sites for CO and CO2 adsorption on magnetite was verified directly by Udovic and Dumesic (43 ). These authors prepared films of magnetite on polycrystalline iron foils and varied the oxidation state of the surface by vacuum-annealing at different temperatures. In short, it was shown by Auger electron spectroscopy and X-ray photo-... 

Figure 3. Surface preparation of the polycrystalline iron foil as received, with damage from cold work (a), ion etched, to remove 2 fan of metal (b) after annealing for 2 hat 500°C to remove etch structure (c), and development of step structure after further annealing for 3 hat 600°C (d).

Spectra from surfaces prepared under dry reduction conditions are dominated by the peak for elemental iron. They all, however, showed a shoulder at 710 eV, characteristic of the presence of unreduced material in, presumably, both ferrous and ferric oxidation states. The position and linewidth of the zero-valent iron peak are different from those of iron foil. A shift of 0.2-0.3 eV to higher binding energy was typical as well as a broader linewidth (2.2 eV for ion foil and ca 3.0 eV for the catalyst). There was no detectable relaxation shift in the iron spectrum. Therefore, the possibility of small-particle effects seems unlikely. The presence of large concentrations of local defects, in addition to possible spectroscopic effects of local variations in the position of the Fermi level, offer plausible explanations for the differences in spectral parameters. 

The reaction is facile at room temperature and in the absence of catalysts only for alkali metals (M = Li, Na, K) and barium [59]. To obtain the derivatives of alkaline earth metals with aliphatic alcohols, it is necessary to apply heat (reflux) and add a catalyst, usually elementary iodine, to clean the surface of the metal applied [110]. The same is true for aluminum alkoxides that can be produced in high yields by reaction of aluminum metal with dry alcohols on addition of l2(s) [2]. For drying the alcohols, one can apply aluminum alkoxides produced even from household aluminum foil, but it is necessary to remember that the latter is doped by some few percent of iron and is not a suitable material for the synthesis of aluminum alkoxides for preparation of high-purity ceramics. 

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