Layer-by-layer stacked vanadium nitride nanocrystals/N-doped carbon hybrid nanosheets toward high-performance aqueous zinc-ion batteries

Aqueous zinc ion batteries (AZIBs) hold great potential in large scale, low-cost energy storage. Unfortunately, their development is limited by the poor performing cathode materials due to their unstable structures and low capacities. Hence, we develop novel layer-by-layer stacked vanadium nitride nanocrystals/N-doped carbon hybrid nanosheets (VN/NC) as cathode materials by in situ thermal conversion of pyrolyzing pentyl viologen intercalated V2O5. The combination of a leaf-like morphology, the nano structure of vanadium nitride crystals and the conductive porous nitrogen-doped carbon nanosheets endow the VN/NC cathode with excellent electrochemical performance in AZIBs. Thus, it delivers a high discharge specific capacity of 566 mA h g(-1) at a current density of 0.2 A g(-1) and a superior rate capability. Most importantly, it exhibits a remarkable cyclic stability with capacity retention of 131 mA h g(-1) (85% of the initial capacity) after 1000 cycles at a current density of 10 A g(-1). The design of the unique VN/NC hybrid nano sheets offers a pathway towards developing high performance electrode materials for energy storage.

Automated summary

Novel layer-by-layer stacked VN/NC materials with excellent electrochemical performance and remarkable cyclic stability have been developed as cathode materials for AZIBs. These materials exhibit high discharge specific capacity and superior rate capability at high current density, providing a new pathway for the development of high-performance electrode materials for energy storage.