缺陷对钠在石墨烯上吸附性能的影响

采用基于密度泛函理论的第一性原理方法,研究了本征石墨烯和缺陷石墨烯吸附钠原子的电荷密度、吸附能、态密度和储存量.结果表明,本征石墨烯中,钠原子的最佳吸附位置为H位,缺陷石墨烯中,钠原子的最佳吸附位置为T_D位.缺陷石墨烯对钠原子的吸附能是-4.423 eV,约为本征石墨烯对钠原子吸附能的2.5倍;钠原子与缺陷石墨烯中的碳原子发生轨道杂化,而与本征石墨烯没有发生轨道杂化现象.缺陷石墨烯能够吸附10个钠原子,与本征石墨烯相比显著提高.因此,缺陷石墨烯有望成为一种潜在的储钠材料.

Effect of detect on the adsorption of Na on graphene

We investigate the charge densities, adsorption energies, densities of states and storage capacities of Na atoms on pristine graphene and defect graphene using the first-principles method of density functional theory combined with the pseudopotential approximation. The results indicate that the most stable site is H site in pristine graphene, while TD site in defect graphene. The adsorption energy of Na on defect graphene is -4.423 eV, which is over 2.5 times that of Na on the pristine graphene. The orbital hybridizations can be observed in the defect graphene, while there is no orbital hybridization in the pristine graphene. Defect graphene can adsorb up to ten Na atoms, which is larger than that of pristine graphene. This work demonstrates that defect graphene is expected to be potential materials for storing Na.