Effect of Ce element on hydrogen storage property of TiMn2-based alloys

• Ce addition significantly improves hydrogen absorption kinetics; Ti0.98Zr0.02Mn1.5Cr0.05V0.43Fe0.09Ce0.02 reaches 90% of its maximum capacity in 137 s at 293 K. • Hydrogen storage capacity first increases and then decreases with Ce content, reaching a peak of 1.85 wt% at x = 0.04. • Thermodynamic analysis shows that Ce improves storage capacity mainly by increasing the enthalpy of hydrogen absorption. • Microstructural benefits include lattice expansion of the C14 Laves phase and a Ce-induced deoxidization effect, enhancing absorption kinetics.