Urchin-like MoS2/MoO2 microspheres coated with GO hydrogel: achieve a long-term cyclability as anode for sodium ion batteries

Abstract

As one of the most promising storage batteries, sodium ion batteries (SIBs) have enjoyed great popularities and been put into research in recent years. However, the larger atomic radius of Na+ sets more limitations when selecting the suitable electrode materials. Mental sulfide and oxide are considered as one of the most prospective electrode materials. MoS2, a typical two-dimensional (2D) layered inorganic material, owns an excellent theoretical capacity, so that it is intensively applied in SIBs. But pure MoS2 shows an instability and sharp decay. In this work, a novel electrode material with ultrathin carbon layer is synthesized through cationic absorption method, one-pot hydrothermal process and gel method. The capacity of MoS2/MoO2/graphene oxide polyvinyl alcohol hydrogel composite reaches up to 350 mAh/g at 0.1 A/g after 100 cycles, and 273 mAh/g at 1 A/g after 1000 cycles. In this paper, we combine theories with experiments to further explore the performance of composite made up of MoS2, GO, and hydrogel as the anode material of SIB.