The electrochemical hydrogenation of amorphous Fe90Zr10 and Fe91Hf9 ribbons has been studied by the potentiostat polarization method. Measurements on heat-treated Fe90Zr10 samples as well as in electrolytes of different pH have also been carried out. The hydrogen content of the charged alloys was determined by gas chromatography. It was found that, depending on the pH of the solution, the amount of hydrogen dissolved in the samples may go through a maximum due to the change in the mechanism of hydrogen evolution. A comparison between the polarization curves of the heat-treated and prepolarized samples revealed that the surface of the ribbons may be altered significantly at high cathodic polarization, resulting in electrochemical behavior similar to that following heat-treatment. This alteration in the state of surface, its “crystallization-like” character, may be reflected not only by the smaller hydrogen uptake of the samples, but by the diminution of their hydrogen retaining ability as well. As a consequence of these results, the initial surface conditions of the as-quenched alloys have also been shown to be of fundamental importance.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry