Boosting Zn-Ion Storage Performance of Bronze-Type VO Ni-Mediated Electronic Structure Engineering.

Aqueous rechargeable zinc-ion batteries are emerging as attractive alternatives for post-lithium-ion batteries. However, their electrochemical performances are restricted by the narrow working window of materials in aqueous electrolytes. Herein, a Ni-mediated VO-B nanobelt [(Ni)VO] has been designed to optimize the intrinsic electronic structure of VO-B and thus achieve much more enhanced zinc-ion storage. Specifically, the Zn/(Ni)VO battery yields a good rate capability (182.0 mA h g at 5 A g) with a superior cycling stability (130.6 mA h g at 10 A g after 2000 cycles). Experimental and theoretical methods reveal that the introduction of Ni in the VO tunnel structure can effectively provide high surface reactivity and improve the intrinsic electronic configurations, thus resulting in good kinetics. Furthermore, H and Zn cointercalation processes are determined X-ray diffraction and supported by characterizations. Additionally, quasi-solid-state Zn/(Ni)VO soft-packaged batteries are assembled and provide flexibility in battery design for practical applications. The results provide insights into the interrelationships between the intrinsic electronic structure of the cathode and the overall electrochemical performance.