Aqueous batteries are suitable for large scale energy storage due to cost and safety concerns. Among all aqueous batteries, rechargeable aqueous zinc-ion battery is a promising choice because zinc electrode has low equilibrium potential, high exchange current density, and high hydrogen evolution overpotential. However, since zinc ion is a divalent cation, it is difficult to find a cathode material in which zinc ion can reversibly insert and extract. In this work, we introduce a novel V₂O₅ nanopaper consisting of V₂O₅ nanofibers and carbon nanotubes as reversible Zn-ion cathode. V₂O₅ has a layered crystalline structure. The spaces between the oxide layers may serve as 2-dimensional diffusion pathways for Zn ions. Meanwhile, the nanofiber morphology endows the material with short ionic diffusion distance and may tolerate high volume change. As a result, the V₂O₅ nanopaper cathode delivers a high capacity of 375 mAh g⁻¹ and long cycle life up to 500 cycles.

由于成本和安全方面的考虑，水电池适用于大规模储能。在所有水性电池中，可充电水性锌离子电池是一个有前途的选择，因为锌电极的平衡电位低，交换电流密度高且析氢过电位高。然而，由于锌离子是二价阳离子，因此难以找到其中锌离子可逆地插入和脱出的阴极材料。在这项工作中，我们介绍了一种由V ₂ O ₅纳米纤维和碳纳米管组成的新型V ₂ O ₅纳米纸，作为可逆的Zn离子阴极。V ₂ O ₅具有层状晶体结构。氧化物层之间的空间可以用作Zn离子的二维扩散路径。同时，纳米纤维形态赋予材料短的离子扩散距离，并且可以耐受高的体积变化。结果，V ₂ O ₅纳米纸阴极提供375 mAh g ^-1的高容量和长达500次循环的长循环寿命。