Dual- Engineering Strategy to Regulate NH4V4O10 as Cathodes for High-Performance Aqueous Zinc Ion Batteries

Aqueous zinc ion batteries (AZIBs) have attracted attention as a promising candidate for secondary battery energy storage due to their safety and environmental benefits. However, the vanadium-based cathode material NH4V4O10 has the problem of structural instability. In this paper, it is found by density functional theory calculation that excessive NH4+ located in the interlayer will repel the Zn2+ during the process of Zn2+ insertion. This results in the distortion of the layered structure, further affects the diffusion of Zn2+ and reduces the reaction kinetics. Therefore, part of the NH4+ is removed by heat treatment. In addition, the introduction of Al3+ into the material by hydrothermal method is able to further enhance its zinc storage properties. This dual-engineering strategy shows excellent electrochemical performance (578.2 mAh g(-1) at 0.2 A g(-1)). This study provides valuable insights for the development of high performance AZIBs cathode materials.

Automated summary

In this paper, it is found that excessive NH4+ in the vanadium-based cathode material NH4V4O10 affects the structural stability and reduces the reaction kinetics of AZIBs. By removing part of the NH4+ through heat treatment and introducing Al3+ through hydrothermal method, the zinc storage properties of the material are enhanced, leading to excellent electrochemical performance. This study provides valuable insights for the development of high performance AZIBs cathode materials.