The main purpose of this study was to investigate the segregation and
oxidation of phosphorus on the polycrystalline iron surface using the
AES and XPS methods. The segregation of phosphorus begins at 600 K and
the maximum concentration of phosphorus on the surface is achieved at
720 K, as in the case of a monocrystalline sample. The segregation of
sulphur begins above 720 K, whereas the phosphorus surface concentrat
ion decreases. The oxidation of the iron surface covered with phosphor
us results in the formation of both the oxygen-phosphorus bonds and th
e oxygen-iron bonds. The different forms of surface species have been
proposed.