Hydrogen Storage Properties of V-Ti-Cr-Fe alloys

摘要

The effects of Ti/(Cr+Fe) ratio, V content and Cr content on the hydrogen storage properties of V-Ti-Cr-Fe alloys were studied in this paper. It was found that Ti/(Cr+Fe) ratio influences largely on the hydrogen storage capacities and the efficient hydrogen storage capacities in the system of 30V-Ti-Cr-Fe alloys. The alloy shows the largest efficient hydrogen capacity at a Ti/(Cr+Fe) ratio of 1.0. When Ti/(Cr+Fe) ratio=1.0, hydrogen storage capacities of V-Ti-Cr-Fe alloys increase with the increase of V content. However, plateau pressures (during the desorption process) decline because of the increase of the lattice parameters. The alloy with 55at% V shows a high capacity about 3.81wt% but a low plateau pressure. Increasing Cr content in that alloy increases the plateau pressure and the efficient hydrogen storage capacity. The alloys of V_(55)Fe_(6.4)Ti_(38.6-x)Cr_x(x=17, 18) show their hydrogen storage capacities exceeding 3.7wt% and efficient hydrogen storage capacities up to 2.23wt%.