Li+, Na+ co-stabilized vanadium oxide nanobelts with a bilayer structure for boosted zinc-ion storage performance

Addressing the structural instability and torpid kinetic limitation has been a pressing while challenging issue for vanadium oxide cathode materials to realize their outstanding performance in rechargeable aqueous zinc-ion batteries (ZIBs). Herein, vanadium oxide nanobelts with a bilayer structure (LiV3O8@NaV3O8, LVO@NVO) have been prepared successfully via a quick one-pot eutectic oxidation process. When evaluated as a cathode for ZIBs, the LVO@NVO shows an amazing capacity of 476 mA h g(-1) at 0.05 A g(-1), superior rate properties (236 mA h g(-1) @ 5 A g(-1)), and excellent cycling capability over 2000 cycles with a capacity-retention of 93.4%. Owing to the pre-intercalated Li+ and Na+ cations and the resulting bilayer structure, higher pseudocapacitance, faster charge-transfer/ion-diffusion kinetics, and a robust architecture have been achieved in the LVO@NVO cathode, which are responsible for the superior zinc-ion storage performance. Furthermore, the energy storage mechanism based on Zn2+ and H+ co-intercalation/extraction has been proved.

Automated summary

In this study, vanadium oxide nanobelts with a bilayer structure were successfully prepared and demonstrated outstanding performance in zinc-ion batteries, including high capacity, excellent rate properties, and cycling stability. The advantages of the cathode material lie in the pre-intercalated ions and bilayer structure, which enable higher pseudocapacitance and faster kinetic reactions.