【摘要】 采用基于密度泛函理论的第一原理赝势平面波方法,计算Ta-LiNH2体系的晶体与电子结构及对解氢性能的影响。负合金形成热与H原子解离能的计算发现:金属元素Ta在LiNH2中少量置换固溶时,体系结构稳定性发生变化,合金化增强了体系的解氢能力。电子态密度(DOS)与电子密度分析发现:Ta合金化提高LiNH2解氢能力的主要原因是合金化元素导致LiNH2体系Fermi能级附近能隙值发生变化以及Li与NH之间的成键作用减弱。更多还原

【Abstract】 Crystal,electronic structure and dehydrogenating of Ta-LiNH2 system have been determined from first-principles calculation based on the density functional theory.The calculated negative heat of formation and dissociation energy of H atom show that when a little Ta dissolve into LiNH2 in a small amount of replacement solution,there are some changes on structural stability,and alloying elements improve the dehydrogenating properties of the system.After comparing the densities of states(DOS) and the charge distribution,it is found that the catalysis effect of Ta on dehydrogenating kinetics of LiNH2 may attribute to the changes of energy gap near the Fermi level and the weakened bonding between Li and NH.更多还原