四元Mg0.9Ti0.1Ni0.9X0.1(X=Mn,Zn,Co,Fe)系列合金的制备及性能研究

用机械合金化法合成了Mg0·9Ti0·1Ni0·9X0·1(X=Mn,Zn,Co,Fe)系列合金.X射线衍射(XRD)结构分析表明,用X部分替代Ni后,促进了Mg0·9Ti0·1Ni合金的非晶化过程.用Co和Fe部分替代Ni提高了合金的放电容量,但却降低了合金的循环稳定性.用Zn和Mn部分替代Ni提高了合金电极的循环寿命,尤其是Mg0·9Ti0·1Ni0·9Zn0·1合金电极经10个充放电循环后,其放电容量仍可达到313·8mA·h/g.对添加Co后的合金进行p-c-T测试发现,Mg0·9Ti0·1Ni0·9Co0·1合金的吸放氢容量明显比Mg0·9Ti0·1Ni合金高,这与电化学所测到的结果一致.

Preparation and Properties of Mg0.9Ti0.1Ni0.9X0.1(X=Mn, Zn, Co, Fe) Quaternary Alloys

The effects of partial substitution of Mg, Ni in Mg-based alloy on its electrochemical and hydrogen storage properties were investigated. Mg-{0.9}Ti-{0.1}Ni-{0.9}X-{0.1}(X=Mn, Zn, Co, Fe) quaternary alloys were synthesized by mechanical alloying(MA) on the basis of the ternary Mg-{0.9}Ti-{0.1}Ni alloy. The X-ray diffraction showed that the X partial substitution of Ni promoted the amorphous process of Mg-{0.9}Ti-{0.1}Ni alloy. It was found that the Co-substituted and Fe-substituted alloys showed enhanced discharge capacities. The cycle life of the alloys was improved with the addition of Mn and Zn, especially Mg-{0.9}Ti-{0.1}Ni-{0.9}Zn-{0.1} alloy remained to keep a higher discharge capacity after the 10 cycles of charge and discharge. The hydrogen content in Mg-{0.9}Ti-{0.1}Ni-{0.9}Co-{0.1} alloy is higher than that in {Mg-{0.9}Ti-{0.1}Ni} alloy, which is in agreement with the result measured by the electrochemistry.