Hydrogen storage properties of nano-composites of Mg and Zr-Ni-Cr alloys

摘要

Mg and Zr-Ni-Cr alloy nano-composite hydrogen storage materials have been prepared by high energy mechanical milling (MM) of Mg powders with either crystalline ZrNiCr and ZrNi_1.6Cr_0.4 powders or mechanically milled amorphous ZrNiCr and ZrNi_1.6Cr_0.4 powders. Nano-composites of amorphous Zr-Ni-Cr alloy and Mg have better desorption kinetics compared to crystalline Zr-Ni-Cr alloy and Mg nanocomposites. Amorphous ZrNi_1.6Cr_0.4 and Mg nano-composites desorb larger amount of H_2 much faster than amorphous ZrNiCr and Mg nano-composites. The nano-composite of 35 wt./100 amorphous ZrNi_1.6Cr_0.4 and Mg releases 4.3 wt./100 H_2 at 300degC in 30 min. X-ray diffraction revealed that there are no reactions between Mg an Zr-Ni-Cr alloys in the milling, activation, and subsequent cycling processes, proving that amorphous ZrNi_1.6Cr_0.4 is an effective hydrogen absorption and desorption catalyst.