Surface structure and catalytic activity of rapidly quenched amorphous iron based alloys III. Effect of surface composition

Abstract

Iron-nickel-boron amorphous alloys in different compositions have been investigated in the hydrogenation of CO. The structure of the surface, its composition and valence state were studied by X-ray photoelectron spectroscopy. The samples in as-received state and after HCl treatment were compared. It was established that before HCl treatment the surface was deeply oxidized and iron oxide was enriched on the dull side, while the shiny side was covered by boron oxide. In the as-received state no correlation was observed between the activity as well as selectivity pattern and the nickel content. After treatment strict proportionally was established between the surface nickel concentration and the activity in the CO hydrogenation. The effect of sorbed hydrogen is also considered in the discussion.