NH4V3O8/carbon nanotubes composite cathode material with high capacity and good rate capability

NH4V3O8/carbon nanotubes (CNTs) composites are synthesized by one-step hydrothermal method. All the samples show the flake-like morphology with the width of up to 5 μm and thickness of 500 nm and the CNTs are clearly observed on the surface of modified NH4V3O8. It is found that incorporation of 0.5 wt% CNTs into NH4V3O8 could greatly improve its discharge capacity and cycling stability. It delivers a maximum discharge capacity of 358.7 mAh g−1 at 30 mA g−1, 55 mAh g−1 larger than that of the pristine one. At 150 mA g−1, the composite shows 226.2 mAh g−1 discharge capacity with excellent capacity retention of 97% after 100 cycles. The much improved electrochemical performance of NH4V3O8 is attributed to incorporation of CNTs, which facilitates the interface charge transfer and Li+ diffusion.

► NH4V3O8/CNTs composites were synthesized by one-step hydrothermal method. ► NH4V3O8/0.5 wt% CNTs showed high discharge capacity and excellent rate capability. ► Incorporation of CNTs is highly beneficial to interface charge transfer and Li+ diffusion.