Intercalation chemistry of graphite-like layered material BC6N for anode of Li ion battery

Films with an approximate composition of BC6N were prepared by the reaction of acrylonitrile with boron trichloride (mole ratio=2:1) at 1470–2070 K under atmospheric pressure. The films obtained at 1470 and 2070 K had graphite-like layered structure whose interlayer spaces were 0.339 and 0.342 nm, respectively. Rapid chemical intercalation of Li into the BC6N prepared at 2070 K was observed in Li+C10H8−/2–MeTHF solution, resulting in formation of the first stage intercalation compound with an interlayer space (d-spacing) of 0.365 nm. The BC6N prepared at 1470 K performed electrochemical charge/discharge cycles similar to those of graphite in 1 M-LiPF6/EC+DEC solution. The first stage compound of LiXBC6N, which was prepared by the electrochemical method, had a d-spacing of 0.355 nm smaller than that of LiC6 (0.370 nm). The small expansion ratio in d-spacing [4.7%={(0.355–0.339)/0.339}×100] could be one of the advantages of the BC6N material for the usage as Li ion battery anode.