- Tytuł:
- Hydrogen Release and Microstructure of $MgH_{2}$ Based Composite Powders Containing a Relevant Amount of $LaNi_{5}$
- Autorzy:
-
Abazović, N.
Aurora, A.
Contini, V.
Mancini, M.
Montone, A.
Vittori Antisari, M. - Powiązania:
- https://bibliotekanauki.pl/articles/1538131.pdf
- Data publikacji:
- 2010-05
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
61.05.cp
61.82.Bg
65.40.-b
68.37.Hk - Opis:
- Micro-composite materials based on $MgH_{2}$ with the addition of a relevant amount of $LaNi_{5}$ have been synthesized by reactive ball milling. The powder microstructure has been studied by a combination of X-ray diffraction and scanning electron microscopy, while the decomposition behaviour and the hydrogen release properties have been obtained by differential thermal analysis and thermo-gravimetric measurements. Both temperature scans and constant temperature isotherms have been used to this purpose. Experimental results allow identifying optimum processing condition for synthesis of material that shows the onset of hydrogen release at temperatures as low as 450 K. The decomposition kinetics has been studied by isothermal measurements which show that the whole process cannot be described by just one mechanism limiting the reaction velocity. In fact in the first decomposition step the reaction is kinetically limited by the second phase nucleation, while, for partially decomposed samples the bulk diffusion appears to limit the process. On the basis of the experimental results we propose a mechanism of phase transformation where a percolating network of the two phases is formed.
- Źródło:
-
Acta Physica Polonica A; 2010, 117, 5; 841-848
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł