硼掺杂双层石墨烯吸附钠的第一性原理研究

采用密度泛函理论(DFT)的第一性原理方法,对Na在本征双层石墨烯(PBLG)和不同掺杂浓度的B掺杂石墨烯(BBLG)表面的吸附性质进行了研究.确定了不同B掺杂浓度时BBLG的最稳定B分布结构,计算了Na在PBLG和不同掺杂浓度的BBLG表面的吸附能.计算结果表明,B原子掺杂倾向于占据上层中对位或次临近位置,并与下层中六边形碳环中心相对,B_4C_(32)的形成能最小;B掺杂浓度的增加使BBLG中上层石墨烯片层结构起伏增大,而对下层影响较小;Na在BBLG表面吸附高度和平均层间距受上层结构起伏影响显著;Na倾向于吸附在B_9C_(27)表面B原子的上方,使原始平面结构产生起伏,Na与B_9C_(27)表面的结合最稳定.

First principle calculations on Na adsorption on the surface of B doped bilayer graphene

The adsorption properties of Na on the surfaces of pristine bilayer graphene (PBLG) and B doped bilayer graphene (BBLG) with different doping concentrations were studied by using the first principles method based on density functional theory (DFT). The most stable B distribution structures of BBLG at different B doping concentrations were determined, and the adsorption energies of Na on the surfaces of PBLG and BBLG with different doping concentrations were calculated. The results reveal that doping B atoms tend to occupy the para or sub-adjacent position in the upper layer, and replace the C atoms relative to the center of the hexagonal carbocyclic center in the lower layer. The formation energy of B4C32 is the smallest. The increasing B doping concentration increases the structural distortion of the upper layer in BBLG, while has the smaller impact on the lower layer. The adsorption height and the average layer spacing are significantly affected by the Na adsorption. Na atom tends to be adsorbed above the B atom of B9C27, leading to the structural distortion, and the binding between Na atom and the surface of B9C27 is the most stable.