Achieving the dehydriding reversibility and elevating the equilibrium pressure of YFe2 alloy by partial Y substitution with Zr

High‐pressure hydrogen storage properties of Ti x Cr 1 − y Fe y Mn 1.0 alloys

“…AB 2 ‐type alloys include Zr‐based (ZrCr 2 , ZrFe 2 , ZrMn 2 , ZrV 2 ), Ti‐based (Ti‐Cr and Ti‐Mn based), and RE‐based (RE: Rare earth metal) alloys. Among AB 2 ‐type alloys, the hydrogen desorption plateau pressure of ZrCr 2 , ZrMn 2 , ZrV 2 , TiMn 1.5 , and RE‐based alloys are all lower than 1 MPa at room temperature. Although Zr‐Fe based alloys have the higher hydrogen desorption plateau pressures, but the hydrogen storage capacities are relatively small due to the heavy atomic weight of Zr .…”

Exploring the Hydrogen-Induced Amorphization and Hydrogen Storage Reversibility of Y(Sc)0.95Ni2 Laves Phase Compounds

“…%, corresponding to the hydride formula Y 0.65 Sc 0.3 Ni 2 H 2.93 . It is noted that the minimum dehydrogenation temperature of the Y 0.25 Sc 0.7 Ni 2 is much lower than that of Y(Zr)Fe 2 compounds [ 24 , 25 , 26 , 27 ]. Therefore, in addition to the improvement in the reversibility due to the reduced R A /R B , the Sc alloying also shows a significant promoting effect in the hydrogen sorption equilibrium pressure because of the reduced lattice constant.…”

“…Rare-earth-based compounds form the largest subset of the AB 2 -type Laves phase compounds [ 23 ], and their potential for hydrogen storage is worthy of more exploration to overcome the HIA problem by compositional and structural modification. Our previous studies show that the B-side substitution with Al and the A-side alloying with Zr could effectively inhibit the HIA and achieve reversible hydrogen storage [ 24 , 25 , 26 , 27 ]. The YFe 1.7 Al 0.3 delivers a reversible hydrogen storage capacity of 1.38 wt.%, but the complete hydrogen desorption must be conducted in a dynamic vacuum at 200 °C [ 24 ].…”

“…The YFe 1.7 Al 0.3 delivers a reversible hydrogen storage capacity of 1.38 wt.%, but the complete hydrogen desorption must be conducted in a dynamic vacuum at 200 °C [ 24 ]. The Zr alloying could realize the reversible hydrogen absorption with the elevated dissociation pressure of YFe 2 because of the reduced cell volume [ 25 ]. Zhang et al [ 28 ] reported that the pseudo-binary Sm 1.25 Mg 0.75 Ni 4 compound could reversibly absorb and desorb ca.…”

Structural and kinetic adjustments of Zr-based high-entropy alloys with Laves phases by substitution of Mg element

“…In this study, the phase structure and hydrogen storage properties of Zr 2 Mg x V 2− y Fe y CrNi high-entropy alloys are affected by the parameters of δ r (atomic size mismatch), Δ χ Allen (Allen electronegativity difference), VEC (average valence electron concentration) and e / a (electron concentration). 29,31–35 VEC = Σ c i VEC i e / a = Z 1 C 1 + Z 2 C 2 + …+ Z m Z m here r i , χ i and VEC i are the atomic radius, electronegativity and valence electron concentration of element i ; c i is the atomic fraction of atom i ; r̄ (=Σ c i r i ) and χ α (=Σ c i χ i ) are the average atomic radius and electronegativity. Z i ( i = 1 − m) is the valence electron number of group i , and C i is the atomic percentage of group I ( C 1 + C 2 + …+ C m = 1).…”