STUDIES OF HYDROGEN STORAGE PROPERLIES AND ABSORPTION-DESORPTION MECHANISM OF FeTi1.3(Mm)y ALLOY

The hydrogen storage properties of FeTi1.3(Mm)y(y=0, 0.013, 0.026, 0.039, 0.052) alloys have been studied in detail. The results show that the activation characteristic of FeTi1.3 alloy is improved dramaticany when a small amount of misch metal (Mm) is added. According to the XRD and SEM, the activation characteristic of the modified alloys is related to the cracks produced in the FeTi matrix by the volume expansion of β-Ti and Mm inclusions as a result of preferential hydrogenation. The activation characteristic is improved by providing chide-free surfaces through which hydrogen can be absorbed readily.The modified alloys not only can be activated at room temperature without any thermal treatment, but also have high hydrogen storage capacity, for example, the desorption content of FeTi1.3(Mm)0.052 alloy is 177.8 mL/g at 333 K.