Experiment Investigation On Mg-based Hydrogen Storage Alloys

Hydrogen storage alloys would play a very important role inapplication of hydrogen energy. Among all kinds of hydrogen storagealloys studied previously,Mg-based alloy is one of the most promisinghydrogen storage materials due to its high hydrogen storage capacity,lightweight, low price and fundamental reserves.We have systematicallystudied hydrogen storage properties of the Mg-Ti compounded alloysystem by experimental research.Mg₇₆Ti₁₂Fe_12-xNi_x(x=0,4,8,12) alloys were prepared by mechanicalalloying and the hydrogen storage properties were investigatedsystematically. The hysteresis between hydrogen absorption anddesorption decreases gradually with increasing the amount of substitutionNi for Fe. Mg₇₆Ti₁₂Fe₈Ni₄ shows the highest hydrogen absorption anddesorption rate among Mg₇₆Ti₁₂Fe_12-xNi_x(X=0,4,8,12) alloys. Fe and Nicoexistence is favorable to improve hydrogen storage properties. ForMg₇₆Ti₁₂Fe₈Ni₄ alloy, the amorphous degree increase with the millingtime,and the amorphous degree increase is unfavorable to improve hydrogen storage capacity.In view of good hydrogen storage properties of Mg₇₆Fe₈Ni₄Ti₁₂alloy, the hydrogen storage properties of Mg₇₆Fe₈Ni₄Ti₁₂ alloy separatelyis analyzed.Multipal compound by ball-mill B and Mg₇₆Ti₁₂Fe₈Ni₄ powdertogether is parepared.The substitution B for Mg can low the temperatureof hydrogen absorption and slow down the speed of hydrogen absorptionand desorption.The plateau pressure ascends and the hysteresis betweenthe hydrogen absorption and desorption decreases with the amount ofsubstitution B for Mg increasing, but the dispersion of the plateau pressurebetween the hydrogen absorption and desorption decreases.