Interlayer-expanded MoS2 vertically anchored on graphene via C─O─S bonds for superior sodium-ion batteries

Abstract

Rational materials design is critical to develop advanced electrodes for high-performance sodium-ion battery. In this work, a well-designed structure with interlayer-expanded molybdenum disulfide (MoS2) vertically anchored on graphene substrates (v-MoS2/rGO) is achieved by one-pot hydrothermal synthesis. The vertical anchored MoS2 and high conductivity graphene sheets provide a good path for electrons/ion transfer. More importantly, the direct linkage of O from functional group on graphene oxide (GO) with edge S of MoS2 (C-O-S) is constructed, which can maintain the stability of the v-MoS2/rGO electrode and enhance its electrons transport rate for the high-rate performance and long cycle life. The assembled sodium-ion battery shows high rate performance (129.2 mAh g−1 at 10 A g−1) and long cycling stability (251.2 mAh g‐1−1 at 2 A g−1 after 1000 cycles with an ultra-low degradation of 10.9 μAh g−1 per cycle). The excellent performance makes the designed structure a fascinating anode for sodium battery.