The Fluorination of Boron?Doped Graphene for CF<i>_x</i> Cathode with Ultrahigh Energy Density

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