Magnesium-nickel hydrogen storage alloys prepared by hydriding combustion synthesis followed by mechanical milling

摘要

Recent progress is reviewed in the preparation of highly active magnesium-based hydrogen storage alloys by the combined process of Hydriding Combustion Synthesis (HCS) and Mechanical Milling (MM). The structural transformation of the alloys during MM determined by means of X-ray Diffraction (XRD) and the hydrogen storage properties of the alloys measured by means of Pressure-Concentration-Temperature (PCT) are reported. The HCS alloy of Mg_(98)Ni_2 after MM showed the highest hydrogen capacity of 5.60 wt.% at 373 K within 100 s and (he dehydriding onset decreased from about 640 K of the HCS product to 480 K of the HCS + MM product. Besides, the absorption capacity at 373 K in 30 s increased from 3.85 wt.% for the HCS + MM product of Mg_(95)Ni_5 without Nb_2O_5 to 5.09 wt.% for that with 1 at.% Nb_2O_5. The results demonstrated that the method of HCS + MM has potential in the preparation of magnesium-based materials for vehicular application.