Graphene-winged carbon nanotubes as high-performance lithium-ion batteries anode with super-long cycle life

• G-CNTs are fabricated by the well-controlled outer-wall peeling of MWCNTs.
• G-CNTs can self-assemble into 3D loose strip-type structure with the curly edges.
• The edge- and defect-rich GNS enhanced the electrochemical performance of LIBs.
• G-CNTs anode delivers reversible capacity as high as 603 mAh g−1 over 2200 cycles.

Graphene-winged carbon nanotubes (G-CNTs) have been prepared by the well-controlled outer-wall peeling of the multi-walled carbon nanotubes (MWCNTs). The final hybrid structure features the few layers of graphene nanosheets attaching to the intact inner walls of CNTs. On one hand, the outer branched graphene nanosheets could suppress the aggregation of CNTs and introduce abundant defects and active-edges for easily accessible chemical interaction. On the other hand, the CNTs could bridge the graphene nanosheets for rapid electron transfer and mechanical robustness. As a result, the G-CNTs was used as the electrode materials exhibiting an extremely steady reversible capacity of 603 mAh g−1 over 2200 cycles at a current density of 1 A g−1 (the corresponding area capacity is 0.16 mAh cm−2 at a current density of 0.26 mA cm−2) and owning a high rate capability much superior to those of the pristine MWCNT-based counterparts. The hierarchical G-CNTs architecture provides a new material platform for development of advanced energy-storage devices.