Contribution of Cation Addition to MnO ₂ Nanosheets on Stable Co ₃ O ₄ Nanowires for Aqueous Zinc-Ion Battery.

ABSTRACT: Zinc-based electrochemistry attracts significant attention for practical energy storage owing to its uniqueness in terms of low cost and high safety. In this work, we propose a 2.0-V high-voltage Zn-MnO₂ battery with core@shell Co₃O₄@MnO₂ on carbon cloth as a cathode, an optimized aqueous ZnSO₄ electrolyte with Mn²⁺ additive, and a Zn metal anode. Benefitting from the architecture engineering of growing Co₃O₄ nanorods on carbon cloth and subsequently deposited MnO₂ on Co₃O₄ with a two-step hydrothermal method, the binder-free zinc-ion battery delivers a high power of 2384.7 W kg^-1, a high capacity of 245.6 mAh g^-1 at 0.5 A g^-1, and a high energy density of 212.8 Wh kg^-1. It is found that the Mn²⁺ cations are in situ converted to Mn₃O₄ during electrochemical operations followed by a phase transition into electroactive MnO₂ in our battery system. The charge-storage mechanism of the MnO₂-based cathode is Zn²⁺/Zn and H⁺ insertion/extraction. This work shines light on designing multivalent cation-based battery devices with high output voltage, safety, and remarkable electrochemical performances.

SUBMITTER: Wang N 

PROVIDER: S-EPMC7539680 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature