Oxygen‐Vacancy and Surface Modulation of Ultrathin Nickel Cobaltite Nanosheets as a High‐Energy Cathode for Advanced Zn‐Ion Batteries

• DOI: 10.1002/adma.201802396
• Publication Date: 2018-07-02T05:32:06Z
• Authors: Yinxiang Zeng; Zhengzhe Lai; Yi Han; Haozhe Zhang; Shilei Xie; Xihong Lu
• Keywords: Cobaltite; Nanosheet; Power density

Abstract The development of high‐capacity, Earth‐abundant, and stable cathode materials for robust aqueous Zn‐ion batteries is an ongoing challenge. Herein, ultrathin nickel cobaltite (NiCo 2 O 4 ) nanosheets with enriched oxygen vacancies surface phosphate ions (P–NiCo 4‐ x are reported as a new high‐energy‐density material rechargeable batteries. oxygen‐vacancy phosphate‐ion modulation achieved by annealing the pristine NiCo using simple phosphating process. Benefiting from merits substantially improved electrical conductivity increased concentration active sites, optimized P–NiCo nanosheet electrode delivers remarkable capacity (309.2 mAh g −1 at 6.0 A extraordinary rate performance (64% retention 60.4 ). Moreover, based on cathode, our fabricated //Zn battery presents impressive specific 361.3 high current density 3.0 in alkaline electrolyte. Furthermore, extremely energy (616.5 Wh kg power (30.2 kW also achieved, which outperforms most previously This ultrafast high‐energy promising widespread application to electric vehicles intelligent devices.