稀土元素掺杂对VH_2解氢性能的影响  

Influence of doped rare earth elements on the dehydrogenation properties of VH_2

作　　者：李荣[1] 罗小玲[1] 梁国明[1] 付文升 

机构地区：[1]重庆师范大学功能材料实验室,重庆400047

出　　处：《物理学报》2012年第9期177-184,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:20971132);重庆市自然科学基金(批准号:CSTC2009BB4243);重庆市教委科技项目(批准号:KJ090810.KJ070809)资助的课题~~

摘　　要：采用密度泛函理论(DFT)的第一性原理的平面波超软赝势方法,研究了La,Ce和Pr掺杂对VH_2的电子结构和解氢性能的影响.计算结果显示La,Ce和Pr掺杂VH_2后晶体模型的费米能级Ef处电子浓度N(Ef)的增加,表明体系结构稳定性减弱,解氢能力增强;电子密度计算也显示V-H之间相互作用减弱,解氢能力增强;同时Mulliken布居数计算结果还显示掺杂以后解氢能力增强与V-d轨道Mulliken布居数减少,V-s轨道Mulliken布居数增加有关.In this paper,using the plane waves ultrasoft pseudopotential method which is base on the first principles of DPT,we study the effects of C,Si,Ge,Sn and Pb alloying on the electronic structure and dehydrogenation properties of VH2.The calculated results show that the electron density of Ef fermi level is higher than that of pure VH2 alloy,exhibiting that the structural stability becomes weakened thus the hydrogen desorption property of VH2 can be improved.Moreover,the computed results of electron density of V-H bond also demonstrate that the interaction between V and H atoms decreases,also showing that the hydrogen desorption property of VH2 is improved.At the same time,it is found from the calculated results that the Mulliken population of V-s orbital increases whereas that of V-d orbital decreases,which is related to the enhanced dehydrogenation property alloyed by La,Ce and Pr.

关 键 词：稀土掺杂 电子结构 解氢性能 第一原理计算 

分 类 号：O482[理学—固体物理]