Pd含量对Mg-Ni合金相形成及贮氢性能的影响研究

Effect of Pd Content on the Phase Formation and Hydrogen Storage Properties of Mg-Ni Based Hydrogen Storage Alloy

采用机械合金化方法合成了Mg-54·7%Ni-x%Pd(x=0、3、10,质量百分比)贮氢材料。通过X射线衍射分析(XRD)和贮氢性能测试,研究了Pd含量对Mg-Ni合金相形成及贮氢性能的影响。XRD分析表明,在0·30MPa的氩气气氛下球磨30h后,粉末没有形成合金相;但在523K吸氢时,Mg-54·7%Ni-x%Pd(x=0,3)与氢气反应均生成了大量的Mg2Ni H4,而Mg-54·7%Ni-10%Pd的氢化物中大部分为MgH2,只形成了少量的Mg2Ni H4。贮氢性能测试结果表明,所制备的材料在473K无需活化即可吸氢;同Mg-54·7%Ni-x%Pd(x=0,10)相比,Mg-54·7%Ni-3%Pd吸放氢速度最快,可逆贮氢容量最大(2·82%,质量百分比)。

Hydrogen storage materials Mg-54.7% Ni-x% Pd（x= 0,3,10, mass ratio） mixture are synthesized by mechanical alloying. The effect of Pd content on the phase formation and hydrogen storage properties of Mg-Ni based hydrogen storage alloy is investigated by XRD and measuring apparatus for hydrogen storage properties. XRD analysis indicates that after ball milling for 30hours under 0.30MPa argon pressure, the powders didn＇t transform to al- loys, but when reacting with hydrogen at 523K, Mg-54.7 % Ni-x% Pd（x= 0,3） transforms to a lot of Mg2 NiH4 while the hydrides of Mg-54.7%Ni-10%Pd are composed of MgH2 and a small quantity of Mg2 NiH4. The results of hydrogen storage properties measured show that the obtained materials can absorb hydrogen at 473K without activation. Comparing with Mg-54.7%Ni-x%Pd（x=0,10）, Mg-54.7%Ni-3%Pd has the fastest speed of hydriding and dehydrid- ing and the most reversible storage capacity （2.82% ,mass ratio）.