Self-assembled interwoven CoS2/CNTs/graphene architecture as anode for high-performance lithium ion batteries

Abstract

Abstract Self-assembled interwoven CoS 2 /carbon nanotubes (CNTs)/graphene (CCG) composite with hierarchical architecture is synthesized via a facile hydrothermal reaction. In the well-designed architecture of CCG, the one-dimensional CNTs and two-dimensional graphene nanosheets construct a highly conductive, porous and flexible network, which can not only effectively suppress the aggregation of CoS 2 nanoparticles and increase the contact area between the composite anode and the electrolyte, but also offer sufficent channels for electron transfer and ionic diffusion and accommodate the volume expansion of the CoS 2 during the charge/discharge process. Therefore, when CCG is used as anode for lithium-ion batteries, it exhibits much better electrochemical performance than that of bare CoS 2 : it delivers a high initial discharge capacity of 993 mAh g −1 at 100 mA g −1 ; it also demonstrates excellent rate performance with a high rate capacity of 212 mAh g −1 even under high current density of 2000 mA g −1 . In this regard, it is promising for CCG to be used as a high-capacity anode for lithium-ion batteries.