▎ 摘　　要

Halogenated graphene can be prepared by liquid phase exfoliation due to good balance between quality and cost. However, this method is severely hampered by lack of understanding of microscopic mechanisms, for example, the influence of polarity of solvent and the reaction between solvent and defect which determines exfoliating and the functionalization. Here, we investigate the effects of HX (X = F, Cl, Br, I), Br-2 and I-2 on the preparation of halogenated graphene using first principles. We found that solvent molecules can act as charge transfer mediators between layers to produce adhesion, which is greatly discourages separation between layers. Besides, the orientation of hydrogen will greatly affect the halogenation of graphene. This work provides abundant theoretical guidance for the preparation of many materials, including but not limited to halogenated graphene, by liquid phase exfoliation, such as the influence of the polarity of solvents and the compatibility of solvents with point defects.