Aqueous zinc-ion batteries (AZIBs) are promising contenders for large-scale energy storage with the merits of their low cost,high safety,environmental friendliness,and competitive gravimetric energy density.Neverthele...Aqueous zinc-ion batteries (AZIBs) are promising contenders for large-scale energy storage with the merits of their low cost,high safety,environmental friendliness,and competitive gravimetric energy density.Nevertheless,suitable cathode materials with long cycle life and adequate capacity are still rare.Herein,we report a nanoflower vanadium tetrasulfide/carbon nanotubes (VS_(4)/CNTs) cathode with high Znstorage performance.We propose a phase transition reaction mechanism from VS_(4)to zinc pyrovanadate in the initial cycles and a reversible intercalation mechanism for Zn^(2+) in zinc pyrovanadate during subsequent cycles.As a result,the cathode delivers a high discharge capacity of 265 mAh g^(-1)at 0.25 A g^(-1)and 182 m Ah g^(-1)at 7 A g^(-1).In addition,the cathode exhibits a long-term cyclability with 93%capacity retention over 1200 cycles at 5 A g^(-1).VS_(4)/CNTs with superior electrochemical performance is a hopeful cathode material in AZIBs.展开更多
基金supported by the National Natural Science Foundation of China (51772257 and 52072328)the Basic Scientific Fund for National Public Research Institutes of China (2019Y03 and 2020S02)。
文摘Aqueous zinc-ion batteries (AZIBs) are promising contenders for large-scale energy storage with the merits of their low cost,high safety,environmental friendliness,and competitive gravimetric energy density.Nevertheless,suitable cathode materials with long cycle life and adequate capacity are still rare.Herein,we report a nanoflower vanadium tetrasulfide/carbon nanotubes (VS_(4)/CNTs) cathode with high Znstorage performance.We propose a phase transition reaction mechanism from VS_(4)to zinc pyrovanadate in the initial cycles and a reversible intercalation mechanism for Zn^(2+) in zinc pyrovanadate during subsequent cycles.As a result,the cathode delivers a high discharge capacity of 265 mAh g^(-1)at 0.25 A g^(-1)and 182 m Ah g^(-1)at 7 A g^(-1).In addition,the cathode exhibits a long-term cyclability with 93%capacity retention over 1200 cycles at 5 A g^(-1).VS_(4)/CNTs with superior electrochemical performance is a hopeful cathode material in AZIBs.
