Study On Hydrogen Storage Properties Of Mg_60-xAl_x Based Solid Solution

In the present work, Mg60-xAlx(x=15,20,25,30)、Mg40Al20+xwt.%Ni (x=0,10,2030), Mg40Al20+5wt.%MO (MO=ZrO2,Nb2O5,V2O5) and Mg40Al15M5(M=Ti, Ni, Fe, V) solid solution alloys was prepared by sintering and mechanical alloying (MA). Then investigations were carried out to study the phase structures and hydrogen storage properties of the solid solution alloys.In the study on Mg60-xAlx(x=15,20,25,30) alloys, which were prepared by MA under5atm Ar after sintering, Bcc and Fcc structures in alloys were produced after milling for150h, The Fcc were likely to turn into Bcc structure with increasing in milling time. The hydrogen storage kinetic and thermodynamic property improved prominently with a reduction in its storage capacity for the addition of Al. It was found that the sample X=20had a better comprehensive property (with its hydrogen capacity up to1.66wt.%after milled for200h).Mg40Al20+xwt.%Ni (x=0、10、20、30) alloys were prepared under5atm H2by an addition of Ni to the mixed powder with the Mg to Al mole ratio of40:20. It was found that Bcc and Fcc structures in alloys were produced after milling for160h, and the peaks in XRD patterns were strengthened in Bcc structure but weakened in that of Fcc with increasing in milling time. All that verified the addition of Ni is helpful to synthesize Bcc structure, and the addition is also good for the improving in hydrogen storage kinetics of alloys, the sample X=20had a better comprehensive property(with its hydrogen capacity up to1.51wt.%after milled for160h).Mg40Al20+5wt.%MO(MO=none,ZrO2,Nb2O5,V2O5) alloys were prepared under5atm H2by sintering and MA methods. It was found that the Al simple substance disappeared after sintering. The mutual diffusion between Mg and Al lead to the emergence of the Mg17Al12phase and surplus Mg simple substance. Bcc and Fcc based solid solutions were found in all samples after milled for150h. The hydrogen storage kinetic and thermodynamic properties were improved prominently with a reduction in its storage capacity for the addition of all kinds of catalysts above, the sample MO=ZrO2had a better comprehensive property(with its hydrogen capacity up to1.74wt.%after milled for150h).Mg4oAl15M5(M=Ti, Ni, Fe, V) alloys were also prepared under5atm H2by sintering and MA methods. The results showed that Bcc based solid solutions were fully or partially synthesized in all samples after milled for150h. All the alloys except X=Ni performed better in hydrogen storage capacity than that of Mg40Al2o alloys, and also in kinetic and thermodynamic properties (with its hydrogen capacity up to1.94wt.%after milled for150h).