Hydrogen sorption properties of compounds based on BCC Ti_(1-x)V_(1-y)Cr_(1+x + y) alloys

摘要

Among the hydrogen storage materials, BCC structure type materials such as V-based alloys reveal promising characteristics due to there reactivity with hydrogen at ambient temperature. A systematic XRD study was performed in order to obtain a cell parameter-composition map in the BCC domain and attempt a correlation with the sorption properties. However, activation of this type of materials may not be straightforward. The aim of this study was to co-melt a main BCC phase with a minor metallic one acting as activating phase. The synthesis of co-melted materials with a specific microstructure starting from Ti_(1-x)V_(1-y)Cr_(1+x + y) (x <= 0.4, y <= 0.3) and Zr_7Ni_(10) alloys was successfully realized. The hydrogen decrepitation of the compound was studied in correlation with its microstructure. Pressure-composition-isotherms were recorded, the absorption and desorption isotherms measured as a function of time (sorption kinetics measurements) show reversible hydrogen uptake up to 2 wt.%.