吸热型金属合金化对钒基贮氢材料性能的影响(英文)

Effect of Addition of Endothermic Metals on the Properties of Vanadium-Based Storage Hydrogen Materials

利用电荷自洽离散变分Xα(SCC-DV-Xα)方法计算了吸热型金属合金化对钒基贮氢材料性能的影响。结果表明:在V63H64中加入吸热型金属Cr,Mn,Fe,Co,Ni后,随着原子序数的增加,V51M12H64中H的净电荷逐渐增加,V的净电荷逐渐减小;氢化物V51M12H64中V-H之间的离子性相互作用逐渐减弱,共价性相互作用逐渐增强。材料放氢的平衡压力与其费米能有很好的一致关系,加入吸热型金属后,氢化物V51M12H64中费米能增加,氢化物更不稳定,从而改善材料的吸放氢性能。

The Xa（SCC-DV-Xa） cluster method was employed to study the effect of endothermic metals on the properties of vanadium-based storage hydrogen materials. The results show that the net charge of H in V51M12H64 increases while that of V decreases gradually with the increase of atomic number, with adding of endothermic alloys-Cr, Mn, Fe, Co, Ni into V63H64. The ionic interaction between V and H in V51M12H64 decreases while the covalent interaction is strengthened contrarily. As well, the equilibrium pressure of releasing hydrogen has good agreement with Fermi energy, that is, the Fermi energy of V51M12H64 increases with the adding of endothermic metals. So the capacity of absorbing and releasing hydrogen is improved by adding of endothermic metals in storage hydrogen materials.