TiFe Hydrogen Storage Alloys Produced by "Hydride Cycle" Method.

Autor: Mayilyan, Davit, Aleksanyan, Anahit
Zdroj: Russian Journal of Physical Chemistry; Dec2023, Vol. 97 Issue 13, p3143-3148, 6p
Abstrakt: The present work was focused on the studies of TiFe hydrogen storage materials synthesis. The TiFe and TiFe + 4 wt % Zr alloys were produced by non-conventional "Hydride Cycle" (HC) method for the first time. For HC method we use metal hydrides synthesized by self-propagating high-temperature (SHS) method as precursor materials. In this work TiH2 and ZrH2 hydrides were used. Crystal structure and lattice parameters of obtained materials were determined by using powder X-ray diffraction (XRD) analysis. Microstructure was studied using scanning microscopy (SEM) and electron dispersive spectroscopy (EDS). It was shown that obtained alloys contain Fe2Ti (C14 Laves phase, MgZn2 structure type, space group P63/mmc) and TiFe (CsCl structure type, space group Pm m) phases. First hydrogenation of TiFe and TiFe + 4 wt % Zr alloys by different processes was investigated. It was shown that compacted pellets of TiFe and TiFe + 4 wt % Zr alloys are able to react with hydrogen in SHS, activation and conventional high-pressure modes without preliminary crushing. Irrespective of alloy composition and hydrogen pressure, SHS combustion temperatures Tc for TiFe and TiFe + 4 wt % Zr alloys were always within the range 80–150°C. These reactions are reversible, which is a very important characteristic for cycling and use of alloys as hydrogen storage materials. These studies concluded that conventional first hydrogenation process of TiFe + 4 wt % Zr at high pressure gives best hydrogen sorption capacity (1.52 wt %). [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
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