▎ 摘　　要

The enhancement of the fluorination degree of carbon fluorides (CFx) compounds is the most effective method to improve the energy densities of Li/CFx batteries because the specific capacity of CFx is proportional to the molar ratio of F to C atoms (F/C). In this study, B-doped graphene (BG) is prepared by using boric acid as the doping source and then the prepared BG is utilized as the starting material for the preparation of CFx. The B-doping enhances the F/C ratio of CFx without hindering the electrochemical activity of the C-F bond. During the fluorination process, B-containing functional groups are removed from the graphene lattice. This facilitates the formation of a defect-rich graphene matrix, which not only enhances the F/C ratio due to abundant perfluorinated groups at the defective edges but also serves as the active site for extra Li+ storage. The prepared CFx exhibits the maximum specific capacity of 1204 mAh g(-1), which is 39.2% higher than that of CFx obtained directly from graphene oxide (without B-doping). An unprecedented energy density of 2974 Wh kg(-1) is achieved for the as-prepared CFx samples, which is significantly higher than the theoretically calculated energy density of commercially available fluorinated graphite (2180 Wh kg(-1)). Therefore, this study demonstrates a great potential of B-doping to realize the ultrahigh energy density of CFx cathodes for practical applications.