钠在空位石墨烯上吸附性能的研究

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空位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,在两种石墨烯中,钠原子的最佳吸附位置都为H位.空位石墨烯对钠原子的吸附能是-2. 46 eV,约为本征石墨烯对钠原子吸附能的3. 4倍;钠原子与空位石墨烯中的碳原子发生轨道杂化,而与本征石墨烯没发生轨道杂化现象.存在一个空位的石墨烯能够吸附5个钠原子,与本征石墨烯相比显著提高.因此,空位石墨烯有望成为一种潜在的储钠材料.

Research of the adsorption of Na on vacancy graphene

We investigate the charge densities, adsorption energies, densities of states and storage capacities of Na atoms on pristine graphene and vacancy graphene using the first-principles method of density functional theory combined with the pseudopotential approximation. The results indicate that the most stable sites are H site in two graphenes. The adsorption energy of Na on vacancy graphene is -2.46 eV, which is over 3.4 times that of Na on the pristine graphene. The orbital hybridizations can be observed in the vacancy graphene, while there is no orbital hybridization in the pristine graphene. Introducing each vacancy into graphene can adsorb up to five Na atoms, which is larger than that of pristine graphene. This work demonstrates that vacancy graphene is expected to be potential materials for storing Na.