Aqueous zinc-ion batteries (ZIBs) are considered to be prospective candidates in energy storage devices because of their excellent safety, crustal abundance, low cost and environmental benignity. Whereas, the design of a satisfied cathode material with a large specific capacity, superior rate performance and long-cycle life is still a significant challenge for ZIBs. Herein, a new strategy is proposed to use W doped V₂O₅ as cathode material for aqueous ZIBs. The W doping can effectively enlarge the lattice spacing and ion migration efficiency of V₂O₅, and the formation of W—O bond can obviously alleviate the capacity decay problem caused by structural damage and low intrinsic conductivity in the cycling process. As a result, the V₂O₅-W cathode exhibits an excellent capacity of 195.0 mA·h/g after 100 cycles at 0.1 A/g, and an impressive rate capability of 243.0 mA·h/g at the high current density of 1 A/g after 1000 cycles. This work provides a simple, efficient and feasible strategy for designing high-performance cathode materials in ZIBs.

Tin-based oxides and their alloys with high specific capacities are considered as promising anode materials for Na-ion batteries. However, the tin-based oxides and their alloys suffer from a large volume variation and particle agglomeration during the charge-discharge process, resulting in electrode pulverization, capacity fading, and poor rate performance. In this paper, Bi/SnO_x particles anchored on an ultrathin carbon layer (Bi/SnO_x@C) were synthesized by a sodium chloride template method, and a uniform Bi/SnO_x@C heterostructure is constructed. The ultrathin carbon layer can effectively inhibit the agglomeration of Bi/SnO_x particles and increase the specific surface area of the electrode material, providing more active sites. Bi/SnO_x can also contribute the more specific capacity. The synergistic effect of ultrathin carbon layer and Bi/SnO_x composite can effectively improve the cycling stability, which is of great significance for the construction of high-performance electrode materials.