STUDY OF INFLUENCE OF HYDROGEN ON STRUCTURE OF MULTILAYER THIN FILMS Pd/Fe

M.V. Starkova, A.A. Katsnelson, E.V. Lichushina, S.V. Sveshnikov

Moscow State University, Faculty of Physics

The changes of structure of the Pd/Fe film, modulated on concentration, caused by influence of hydrogen are investigated. The saturation of samples by hydrogen absorption was carried out three times consecutively every 336 hour by an electrochemical method (electrolyte - 4 % a water solution NaF, time of saturation 5 minute, density of a current 16 mA/cm²).

Directly after the first saturation on X-ray diffraction data the reflexes concerning to betta-phase Pd (111) were observed. After current 1 hour degassing they disappeared. During onsequent degassing were observed weak change of interatomic distances, which were stabilized in 24 hours after hydrogen absorption. After second hydrogen absorption of change carried similar character.

After third hydrogen absorption it was observed strongly to hade a sharp cut-off of the satellites peaks describing modulated structure and sharp increasing of Pd-Fe lattice parameters. Widening of lines testifies about increase of quantity of defects. After 168 hours degassing, the stabilization of structure was not observed.