Layered Co doped MnO2 with abundant oxygen defects to boost aqueous zinc-ion storage

Plasma treatment and element doping are combined to prepare Co-MnO2 rich in oxygen vacancies, which has excellent electrochemical performance as the cathode of Zn ion battery. The synergistic effect of Co element and MnO2 could optimize the conductivity of the material and increase the specific capacity. [Display omitted] •Co-MnO2 nanowires with abundant oxygen vacancies were successfully prepared.•The oxygen vacancy and polycrystalline/monocrystalline mixed phase could improve the conductivity.•Co-MnO2 exhibits enhanced Zn ions storage performance. Zinc Manganese oxide (Zn/MnO2)-based aqueous battery is favored due to their high specific capacity, security and cost performance. Nevertheless, they usually problems of unstable cyclic structure and slow diffusion kinetics, restricting their practical application. Here, we have successfully synthesized a Co doped MnO2 cathode material with abundant defects on a carbon cloth substrate. Through a simple hydrothermal method, the Co element can be lightly intercalated in the two-dimensional (2D) layered α-MnO2 nanowires, inhibiting the structural transformation during the cycle and improve the stability of the material. Meanwhile, plasma technology facilitates the formation of oxygen vacancies in the electrode material, which not only accelerate electron diffusion but also improve the conductivity. Therefore, Zn/Co-MnO2 battery can reach a specific capacity of 511 mAh g−1 at 0.5A g−1 and the retention rate accomplish 98% at high current density. This research puts forward a strategy of element doping and physical preparation of oxygen vacancies, which provides the possibility to develop reversible Zn/MnO2-based aqueous battery cathode materials with high-performance.