利用基于密度泛函理论的第一性原理计算了空位和B替位掺杂对Si在石墨烯上吸附的影响.结果表明:对完整的石墨烯结构,Si吸附在桥位最稳定,Si吸附改变了石墨烯中C原子的自旋性质;空位和B替位掺杂均加强了Si在缺陷处的吸附,空位对Si在石墨烯上吸附的影响相对较大;B掺杂改变了Si的稳定吸附位置(由桥位移到顶位);Si在空位和B掺杂石墨烯上吸附,体系不具有磁性;B掺杂提高了石墨烯体系的导电性能;单空位缺陷不易形成,结构不稳定,B掺杂结构相对较稳定.
First-principles calculations based on density functional theory were carried out to study the effects of monovacancy and boron doping on Si adsorption on graphene.We found that Si single atom,sitting above the bridge site of defect-free graphene,was the most stable configuration.The spin properties of the C atoms change after Si adsorption.In our calculations,monovacancy and substituting with B atoms enhanced Si adsorption on graphene and monovacancy was more effective than the B dopant.No magnetic moment was observed for the Si adsorbed on these two systems.B doping induces a stable Si adsorption position from the bridge site to the top site and increases the conductivity of the graphene system.By comparison,B doping in the graphene system is relatively stable while the monovacancy system is not.