3D MoS₂–Graphene Microspheres Consisting of Multiple Nanospheres with Superior Sodium Ion Storage Properties

Abstract

A novel anode material for sodium-ion batteries consisting of 3D graphene microspheres divided into several tens of uniform nanospheres coated with few-layered MoS 2 by a one-pot spray pyrolysis process is prepared. The fi rst discharge/charge capacities of the composite microspheres are 797 and 573 mA h g −1 at a current density of 0.2 A g −1. The 600th discharge capacity of the composite microspheres at a current density of 1.5 A g −1 is 322 mA h g −1 .The Coulombic effi ciency during the 600 cycles is as high as 99.98%. The outstanding Na ion storage properties of the 3D MoS 2 -graphene composite microspheres may be attributed to the reduced stacking of the MoS 2 layers and to the 3D structure of the porous graphene microspheres. The reduced stacking of the MoS 2 layers relaxes the strain and lowers the barrier for Na + insertion. The empty nanospheres of the graphene offer voids for volume expansion and pathways for fast electron transfer during repeated cycling.

Interlayer Nanoarchitectonics of Two‐Dimensional Transition‐Metal Dichalcogenides Nanosheets for Energy Storage and Conversion Applications

“…The 3D MoS 2 -graphene microspheres show superior sodium ion storage properties with high rate capability (234 mA h g −1 at 10 A g −1 ) and excellent cycling stability (322 mA h g −1 at 1.5 A g −1 after 600 cycles). [116] Shao and co-workers recently synthesis of 3D interconnected and hollow nanocables composed of multiwalled carbon@MoS 2 @carbon as outstanding anodes for SIBs. In such a hierarchical architecture, the ultrathin MoS 2 nanosheets with an expanded interlayer spacing of 0.95 nm are sandwiched between and doubly protected by two layers of porous carbon, that is, 3D interconnected and hollow carbon nanofibers (3D-HCNFs) and a layer of polydopamine (PDA)-derived carbon shell.…”

Two-Dimensional (2D) Nanomaterials towards Electrochemical Nanoarchitectonics in Energy-Related Applications

“…292 Sheet-on-sheet structured MoS 2 /rGO nanocomposites show a reversible Na ion storage capacity of 338 mA h g ¹1 293 and 702 mA h g ¹1 , respectively. 294 The high abundance and low cost of Na and its low redox potential (0.3 V above that of lithium) makes rechargeable sodium ion batteries (SIBs) an alternative to LIBs.…”

Recent Advances in Sodium-Ion Battery Materials

“…2D-layered MoS 2 has attracted significant attention. Conductive species, such as graphene [187][188][189][190], carbon tubes [191], carbon fibers [192] and carbon paper [193], were used to construct nanostructured MoS 2 electrodes. Dou and co-workers have designed unique hierarchical sandwich-like MoS 2 /graphene composites, which displayed a high reversible capacity of 640 mAh g −1 with a stable cycle life over 250 cycles [194].…”