INVESTIGADORES
MEYER Marcos
congresos y reuniones científicas
Título:
Mechanically Alloyed Mg-Fe-Ti Powder Mixtures as Hydrogen Reservoirs
Autor/es:
M. MEYER; L. A. MENDOZA ZÉLIS
Lugar:
Gijon
Reunión:
Simposio; ISMANAM INternational Symposium on Metastable, Amorphous and Nanocrystalline Materials; 2011
Resumen:
Following recently reported research [1] on Mg-Fe-Ti
films with remarkable hydrogen sorption properties, we attempted an
investigation on mechanically alloyed powder mixtures of identical composition.
We milled samples of nominal composition Mg80Fe10Ti10,
Mg70Fe15Ti15 and Mg60Fe20Ti20
in H2 ambient, till a steady state with no further H2
absorption was attained. The resulting powders were then characterized and
submitted to several discharge-charge cycles. We extend our investigation to
samples of nominal composition Mg69Fe26Ti5, Mg64Fe26Ti10
and Mg64Fe31Ti5 in order to also explore a
compositional region with reported [2] optimal sorption properties for similar Mg-Ni-Ti
films.
Each milled sample was dynamically discharged
(charged) by increasing (decreasing) the temperature at a given starting H2
pressure. The resulting curves were analyzed to extract approximate
values of the equilibrium (T,P) data for H2 desorption (absorption).
All the samples were characterized by X ray diffraction and Mössbauer
spectroscopy on 57Fe, before and after their cycling in H2.
The results were analyzed
in the framework of possible mechanisms for the transition metals catalytic
action on the H2
sorption processes and the influence of the sample microstructure.