Development of Ti–Cr–Mn–Fe based alloys with high hydrogen desorption pressures for hybrid hydrogen storage vessel application

Three series of Ti–Cr–Mn–Fe based alloys with high hydrogen desorption plateau pressures for hybrid hydrogen storage vessel application were prepared by induction levitation melting, as well as their crystallographic characteristics and hydrogen storage properties were investigated. The results show that all of the alloys were determined as a single phase of C14-type Laves structure. As the Fe content in the TiCr1.9−xMn0.1Fex (x = 0.4–0.6) alloys increases, the hydrogen absorption and desorption plateau pressures increase, and the hydrogen storage capacity and plateau slope factor decrease respectively. The same trends are observed when increasing the Mn content in the TiCr1.4−yMnyFe0.6 (y = 0.1–0.3) alloys, except for the plateau slope factor. Compared with the stoichiometric TiCr1.1Mn0.3Fe0.6 alloy, the titanium super-stoichiometric Ti1+zCr1.1Mn0.3Fe0.6 (z = 0.02, 0.04) alloys have larger hydrogen storage capacities and lower hydrogen desorption plateau pressures. Among the studied alloys, Ti1.02Cr1.1Mn0.3Fe0.6 has the best overall properties for hybrid hydrogen storage application. Its hydrogen desorption pressure at 318 K is 41.28 MPa, its hydrogen storage capacity is 1.78 wt.% and its dissociation enthalpy (ΔHd) is 16.24 kJ/mol H2. Ti–Cr–Mn–Fe based alloys with high hydrogen desorption plateau pressures have been developed for hybrid hydrogen storage vessel application. Among the studied alloys, Ti1.02Cr1.1Mn0.3Fe0.6 shows the best overall performance for hybrid hydrogen storage. Its hydrogen desorption plateau pressure at 318 K is 41.28 MPa, its hydrogen storage capacity is 1.78 wt.% and its dissociation enthalpy is 16.24 kJ/mol H2. [Display omitted] •Ti–Cr–Mn–Fe based alloys have been developed for hybrid hydrogen storage application.•Partial substitution of Cr with Fe or Mn improves the hydrogen desorption pressure.•Ti super-stoichiometry in Ti–Cr–Mn–Fe alloys improves the hydrogen storage capacity.•Ti1.02Cr1.1Mn0.3Fe0.6 shows the best overall properties for hybrid hydrogen storage.