Ce-Doped TiZrCrMn Alloys for Enhanced Hydrogen Storage

Hydrogen storage is one of the key steps that restricts the large-scale application of hydrogen energy and fuel cells. In this work, we developed an efficient H2 storage material by Ce doping in the TiZrCrMn alloy and systemically studied the effect of Ce on the microstructure, activation, and hydrogen storage properties. The results indicated that Ce addition in the Ti0.8Zr0.2Cr0.75Mn1.25 alloy did not change the major phase structure of Laves C14 but slightly increased the lattice constants and resulted in the formation of a CeO2 phase. It is interesting to find that Ce inhibited the enrichment of the Ti phase, inducing a homogeneous elemental distribution throughout the alloy. Hydrogenation and dehydrogenation tests indicated that the Ce-added alloy exhibited H2 absorption and effective desorption capacities of up to 1.98 and 1.79 wt %, respectively, higher than those of TiZrCrMn alloys reported in the literature. Ce also improved the activation of the alloy at room temperature and enhanced the cyclic performance during the hydrogenation and dehydrogenation. The activation energy, enthalpy change, and entropy change of the alloys upon hydrogenation and dehydrogenation were calculated and a small change was observed after Ce addition.