The effect of Si on V_(30)Ti_(35)Cr_(25)Fe_(10) BCC hydrogen storage alloy

摘要

The hydrogen storage properties and microstructure of (V_(30)Ti_(35)Cr_(25)Fe_(10))_(1-x)Si_x (x = 0-2.5 at. percent) alloys were studied in this paper by PCT measurement, XRD and SEM/EDS. Laves phase appears in all Si-containing alloys (x >= 0.32 at. percent) except for BCC main phase, and the activation property is improved obviously by the occurring of Laves phase. The hydrogen absorption and desorption capacities decrease and the plateau pressures increase with the increase of Si content. Si exists mainly in Laves phase. The decrease of lattice parameter and the occurring of Laves phase by adding Si are the main reasons for the change of the hydrogen storage properties of the Si-containing alloys.