Multifunctional B/N Co‐Doped Graphene Interlayer for Fast and Stable Lithium‐Sulfur Batteries

Abstract

AbstractA boron (B)/nitrogen (N) co‐doped graphene is synthesized via an two‐steps method and used as an interlayer for lithium‐sulfur (Li−S) batteries. Due to the excellent electronic conductivity and dense sheet constructure of graphene, it can improve the conductive network, reduce the pores of polypropylene (PP) membrane, and consequently inhibit the penetration of polysulfide in Li−S batteries. More importantly, the co‐doped B and N atoms play the role of Lewis acid‐base, which have a strong adsorption capacity to lithium ions and as well as sulfur ions during reactions, and thus inhibit the “shuttle effect” and accelerate the conversion reactions of polysulfides. Based on this multifunctional interlayer, the cells exhibit a high initial capacity of 1448 mAh g−1, and achieve a reversible capacity of 578 mAh g−1 under a large rate of 2 C after 350 cycles with a capacity decay of 0.015 % per cycle. These results demonstrate the enormous potential of the B/N co‐doped graphene as the interlayer for high‐performance Li−S batteries.