W. Meisel et al., PHASE-COMPOSITION OF FE-CONTAINING LANGMUIR-BLODGETT LAYERS AFTER THERMAL-TREATMENT IN A REACTIVE ATMOSPHERE, Fresenius' journal of analytical chemistry, 346(1-3), 1993, pp. 110-113
By the Langmuir-Blodgett technique, mono- and multilayers of ferric st
earate were drawn onto silicon wafers. They were thermodesorbed in air
at 250-300-degrees-C, and the layers formed in this way were found to
consist of gamma-FeOOH with defective stoichiometry. By heating in H-
2, the layers can be reduced to Fe2+ and even to alpha-Fe. The latter
is magnetically ordered and highly corrosion resistant. Chloride ions,
however, induce fast corrosion. FeCl2, formed by this corrosion, is r
ather unstable and transforms to an Fe3+ phase. The high corrosion res
istance of the metallic Fe layer is assumed to be due to its excellent
homogeneity. The experiments were performed using XPS, AES, CEMS, and
SEM.