Dope/Compound Experiment And Electronic Structure Investigation On Mg₂Ni-based Hydrogen Storage Alloys

Mg2Ni-based alloy is one of the most promising hydrogen storage materials due to its high hydrogen storage capacity, lightweight, low price and fundamental reserves. We have systematically studied the hydrogen storage properties of the Mg2Ni-based alloy by both theoretical calculation and experimental research.Mg_2-xSn_xNi (x=0,0.05,0.1,0.15,0.2) alloys were prepared by sinter and ball-mill method. Then the microstructure was studied in XRD, and the experiments about hydrogen storage and electrochemical properties were developed. We found that the crystal structures of the doped alloys remain unchanged, the degree of amorphous increases with the amount of x increasing. For hydrogen storage properties, the hydriding/dehydriding temperature of doped alloys fall down, and the decompose-enthalpies of their hydrides decrease which mean that the stability of the hydrides reduce. At the same time, their hydrogen storage capacity descend, and two hydriding/dehydriding pressure plateaus occur in PCI curves. In the aspect of electrochemistry, the discharge capacity is improved with the amount of...