掺杂V对LiNH_2解氢性能的第一原理计算  

First Principle Calculation of Doped V Dehydrogenating Properties of LiNH_2

作　　者：袁江[1,2] 宋新华[1,2] 卢端敏[1] 候德政[1] 

机构地区：[1]张家界航空工业职业技术学院,张家界427000 [2]湖南大学汽车车身先进设计制造国家重点实验室,长沙410082

出　　处：《材料导报》2013年第20期156-160,共5页Materials Reports

基　　金：国家自然科学基金(51175165);湖南省张家界航空工业职业技术学院项目(ZHKT2011-020)

摘　　要：采用基于密度泛函理论的第一性原理赝势平面波方法,研究了V元素掺杂对LiNH2的电子结构和解氢性能的影响。计算结果显示,V元素掺杂LiNH2晶体模型的负合金形成热减少,LiNH2体系结构的稳定性减弱,合金化增强了体系的解氢能力。Mulliken集居数、电子态密度与电子密度的进一步分析发现:掺杂V以后,通过电荷补偿,N与H之间离子性相互作用增强,共价性相互作用减弱;费米能级(EF)处键峰值增大,能隙ΔEH-L变窄,LiNH2的解氢能力提高。Using the plane waves ultrasoft pseudopotential method based on the first principles of DFT, the in- fluence of doping V on the electronic structure and dehydrogenation properties of LiNH2 was studied. The results show that the negative heat of formation there are weaken the structural stability, alloying elements befit to improve the de- hydrogenating properties of LiNH2. After comparing the mulliken populations and the densities of states and the charge distribution, it is found that the catalysis effect of V on dehydrogenating kinetics of LiNH2 may attribute to the changes of N and H between ionic interaction is enhanced and covalent interaction weakened, the Fermi level （EF） place peak value of bond are increased and the energy gap near the Fermi levelΔE,-L are narrows.

关 键 词：赝势平面波 LiNH2 合金形成热 电子结构 解氢性能 

分 类 号：TG139.7[一般工业技术—材料科学与工程]