Interlayer expanded MoS2 enabled by edge effect of graphene nanoribbons for high performance lithium and sodium ion batteries

Abstract

Interlayer expanded MoS2 grown on graphene nanoribbon aerogel (GNRA) has been synthesized and used as anode material for high performance lithium and sodium ion batteries (LIBs, SIBs). The edge effect of graphene nanoribbons including the enormous oxygen functional groups and the insertion of edge carbon layers leads to the formation of MoS2 with large interlayer spacing. The expansion boosts the intercalation and diffusion of alkaline ions (Li+ and Na+) in layered MoS2. As tested for LIBs, the MoS2/GNRA electrodes exhibit excellent rate performance as capacity of 303 mAh g−1 can still be achieved even at a high current density of 30 A g−1. Long cycling performance for 1800 cycles at 10 A g−1 further confirms their superior stability. The hybrid structures also show good performance for SIBs, specific capacities of 372–203 mAh g−1 are obtained at a current density range of 0.5–15 A g−1. A capacity of 158 mAh g−1 is still kept even after 1500 cycles at 5 A g−1. This work provides a facile method to control the structure of layered metal sulfides and confirms their potential applications in energy storage and conversion.