Li吸附对石墨烯、BC5、C5N电学性质影响的第一性原理研究（英文）

First-principles Calculations on Electrical Properties Effect of Li on Graphene,BC5,C5N Surface

基于密度泛函理论(DFT)的第一性原理方法,对Li在本征石墨烯和BC5,C5N表面最稳定位置的吸附进行了结构优化,计算了本征石墨烯及BC5,C5N吸附Li前后的能带结构,态密度,电荷转移,差分电荷密度和结合能。计算结果表明,B掺杂浓度为16.67%(原子分数)时可显著提高石墨烯的Li吸附能,N掺杂浓度为16.67%(原子分数)时减弱了石墨烯的Li吸附能。吸附Li后的graphene-Li、BC5-Li和C5N-Li体系均显示出金属性,且Li与石墨烯、BC5和C5N体系间存在离子键和共价键的混合。

The geometrical structures of Li atom adsorption on the most stable sites of pristine graphene and BC5,C5N surfaces were optimized by using first-principles method based on density functional theory(DFT).The band structures,density of states(DOS),charge transferring,electron density differences and binding energies of both pristine graphene and BC5,C5N were calculated theoretically.The results revealed that when the B-doping concentration is 16.67%,the adsorbing energy of Li atom on graphene will be remarkably enhanced;however,when the N-doping concentration is 16.67%,the adsorbing energy of Li atom on graphene will be decreased.Graphene-Li,BC5-Li and C5N-Li all have metal properties.There is mixed ionic and covalent bonds between Li and graphene,BC5 and C5N.