Hydrogen evolution from Zr-based amorphous and quasicrystalline alloys
نویسندگان
چکیده
The combination of local tetrahedral order and favorable chemical composition makes amorphous and quasicrystalline Zr–Cu–Ni–Al alloys good candidates for hydrogen storage applications. Hydrogen evolution from these alloys has been studied by means of thermal desorption spectroscopy (TDS). The characteristics of hydrogen desorption from an initially quasicrystalline phase are analyzed in detail for the first time. Spectra analysis is supported by data from variety of other experimental techniques, such as differential scanning calorimetry (DSC), Auger electron spectroscopy (AES), elastic recoil detection analysis (ERDA) and transmission electron microscopy (TEM). Hydrogen desorption from both alloys is found to be a very complex process, being affected by phase transformations that take place during annealing, by hydride formation, and by the formation of a thin zirconium oxide on the surface. 2000 Elsevier Science S.A. All rights reserved.
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