Li-Storage Performances of Liquid-Phase Exfoliated Two-Dimensional Gallium Sulfide Nanosheets/Single-Walled Carbon Nanotubes Composite

Abstract

The two-dimensional nanosheets (2D NS) of layered metal chalcogenide (MC) evoke huge research attention in lithium-ion battery (LiB). Nevertheless, their undesirable electrical conductivity and complicated synthesis procedures negatively the prospects of these NS as a competive LiB electrode material. To this end, we have developed facile, scalable approach, liquid-phase exfoliation (LPE)/filtration, to produce binder-free GaS NS/SWCNT flexible conductive composite for LiB. The uniform GaS NS/SWCNT composite possesses several advantages at the same time: (i) The open channels in the nanostructure result in faster Li+ diffusion. (ii) The entangled SWCNT network forms developed electron transport paths, lowering the junction resistance. (iii) SWCNT could function as the “conductive binder”, maintaining the structural integrity of the thick electrode without losing electrical contact with the current collector. The resultant GaS NS/SWCNT composite exhibited excellent rate capability, high specific capacity (838 mAh g-1) and a remarkably high utilization of GaS NS (1161 mAh g-1), demonstrating electrochemical performances competitive with those of other reported 2D MC-based electrode systems. This work opens up vast opportunities for other families of MC NS to be scalably processed into porous, binder-free, flexible conductive thin films and composites with a broad range of applications.