Facile hydrothermal synthesis of V2O5 nanofibers as cathode material for aqueous zinc-ion batteries

Abstract

Aqueous zinc-ion batteries (AZIBs) are now vigorously explored as a class of novel and competitive candidates for large-scale energy storage in terms of high safety, eco-friendliness and low cost. In order to realize efficient Zn-storage with desirable cycling stability and rate capability, constructing suitable cathode materials that possess reliable host structure and fast Zn2+ diffusion kinetics makes a lot of sense. Herein, novel V2O5 nanofibers were facilely synthesized via a hydrothermal method and employed as a cathode material for AZIBs. By matching with aqueous Zn(CF3SO3)2 electrolyte, the cathode is able to achieve a specific capacity as high as 264.5 mAh g−1 at 200 mA g−1. Even conducted at a large current density of 2000 mA g−1, a considerable rate capability of 132.6 mAh g−1 can also be delivered. In addition, electrochemical reaction kinetics and ion diffusion mechanism were initially conducted to uncover the insights for efficient Zn-storage. This work is anticipated to offer feasible strategy for the design and fabrication of promising vanadium-based cathode materials for rechargeable AZIBs.