Mechanical activation of hydrogen sorption with intermetallic compounds LaNi5 and TiFe in powder systems

Hydrogen storage systems using modified sorbents for application in automobile manufacturing

“…The formation of metal hydrides is highly dependent on the temperature [4,8,18] and the pressure. The higher temperatures and pressures are the more intense this process is and a greater quantity of hydrogen will be stored by this mechanism.…”

High-pressure torsion of TiFe intermetallics for activation of hydrogen storage at room temperature with heterogeneous nanostructure

“…Fig First, hydrogen absorption is negligible in the annealed sample, indicating that an activation process is necessary in consistency with Refs. [1][2][3][4][5][6][7][8][9][10][11][12][13]. Second, after HPT processing, the sample absorbsw1.7 wt.% of hydrogen without any activation process, and this value is fairly close to the maximum capacity of hydrogen storage in TiFe (1.9 wt.%) [1].…”

“…The material usually requires exposure to H 2 atmosphere under high pressures as several Mega-Pascals at elevated temperatures as 673 K for the activation before hydrogenation. Although there are several approaches for easier activation such as setting compositions to Ti-rich from the stoichiometric value [8], addition of Mn [9], Ni [10] and Pd [2], addition of O 2 to the H 2 atmosphere [11], and nanostructuring by ball milling [12,13], the material usually needs the activation process before hydrogenation. Processing using severe plastic deformation (SPD) [14,15] may be a solution to activate the TiFe for hydrogenation.…”

Tailoring the Kinetic Behavior of Hydride Forming Materials for Hydrogen Storage

“…In the case of room temperature hydrides, the presence of transition metals like Pd and Ni notably improves their activation behavior and kinetic properties. This fact was attributed to the active sites of these transition metals, located on the metal or alloy surface, which facilitated the hydrogen molecule dissociation and penetration across the oxides generated on the metal or alloy surface [67][68][69]. These hydrides are commonly prepared by arc melting since, as mentioned in Section 4.2, the milling process can cause hydrogen capacity losses.…”