Paper EH-TuP4
Synthesis and Hydrogen Properties of Beryllium Intermetallic Compound

Tuesday, December 9, 2014, 4:00 pm, Room Mauka

Beryllium intermetallic compounds have shown a variety of excellent properties, such as neutron multiplier, refractory function, hydrogen storage, superconductivity and so on. Be₁₂M compounds (M=Ti, V and Zr) have been investigated as neutron multiplier in fields of fusion reactor while Be₁₇M₂ compounds have been focused on refractory materials. In addition, Be₂M have been known as a Laves phase which is characterized by an A₂B type compound performing higher H₂ gas storage potential. Although great interest on hydrogen properties of Be₂M owing to its lower density has been aroused from viewpoints of reactivity with H₂O, trap site of hydrogen and amount of H₂ gas in this compound, few studies on the Be₂M found and its data base is still unsatisfactory.

In this study, we report on preliminary synthesis of Be₂Ti compound and its properties, such as hydrogen generation due to reaction with H₂O and hydrogen storage. Additionally, first principles calculation of hydrogen trap site in this compound was carried out in order to compare to empirical data.

X-ray diffraction profiles and electron probe micro-analysis results clarify that the preliminary synthesis of Be₂Ti was successful by homogenization treatment and plasma sintering. Hydrogen generation rate of the Be₂Ti by a reaction with 1 % H₂O increased as test temperature increased. High temperature exposure with H₂O leads to formation of TiO₂ on the surface. In addition, hydrogen storage result of Be₂Ti evaluated by pressure-concentration-temperature curve depicts that Be₂Ti indicated H₂ gas storage concentration with 1.6 w.t. % at 323 K when the H₂ pressure increases up to 10 MPa. According to the first principle calculation, there were two hydrogen trap sites, tetrahedron and center of triangle with solidus energies of -0.52 and -0.05 eV, respectively, indicating maximum trap site with 5.4 w.t. %.