Dresden 2017 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 21: Functional Materials II
MM 21.3: Vortrag
Montag, 20. März 2017, 17:45–18:00, IFW D
In-situ dehydrogention and positron annihilation spectroscopy of Mg2Fe thin films — •Thu Trang Trinh1, 2, Marciej Oskar Liedke2, Andreas Wagner2, Rene Heller2, Herman Schreuders3, Bernard Dam3, Kohta Asano4, and Kay Potzger2 — 1Technische Universität Dresden, 01062 Dresden, Germany — 2Helmholz-Zentrum Dresden Rossendorf, 01328 Dresden, Germany — 3Delft University of Technology, 2629HZ Delft, Netherlands — 4AIST, Tsukuba 8565, Japan
Mg2Fe hydride belongs to the most promising candidates for application as light weight storage material in a future hydrogen economy. Recently, it has been shown that due to chemochromism, Mg2Fe is also a low-cost and rare-earth-free candidate for switchable mirrors upon hydrogen loading. However, the interaction between defects and hydrogen on the atomic scale remains not completely understood, despite the fact that the behaviour of hydrogen in metals is strongly affected by the presence of defects. Due to the positive binding energy between hydrogen and vacancy, the hydrogen atoms get trapped at existing defects which thus play an important role for the hydride formation.
We present a comparative and systematic study on the defects in Mg2Fe and their interaction with hydrogen by means of positron annihilation spectroscopy (PAS). We present first results of the temperature dependence of the open volume defects during annealing of Mg2FeH6 thin films, which was performed by an unique high vacuum system for defect manipulation and analysis (AIDA) at the positron beamline at the Helmholtz-Zentrum Dresden-Rossendorf.