Inhibition of Manganese Dissolution in Mn_2O_3 Cathode with Controllable Ni~(2+) Incorporation for High-Performance Zinc Ion Battery

摘要

Manganese-based materials are considered potential cathode materials for aqueous zinc ion batteries (ZIBs). However, the dissolution of manganese leading to an abrupt decline of capacity and the sluggish electrochemical reaction kinetics are still the main bottlenecks restricting their further development. Herein, a NiMn-layered double hydroxide-derived Ni-doped Mn2O3 (NM) is developed to suppress the dissolution of manganese. The incorporation of Ni2+ can promote electronic rearrangement and enhance the conductivity, ultimately improving the reaction kinetics and electrochemical performance of the NM. Moreover, the doped Ni2+ can effectively stabilize the Mn-O bond of Mn2O3 by reducing the formation energy. In addition, the storage mechanism based on the simultaneous insertion and transformation of H+ and Zn2+ is demonstrated. Interestingly, the Ni-doped Mn2O3 shows a high specific capacity of 252 mAh g(-1) (0.1 A g(-1)), three times more than the pure Mn2O3 (72 mAh g(-1)). The capacity retention (approximate to 85.6% over 2500 cycles at 1.0 A g(-1)) is also more excellent when comparing with the Mn2O3 cathode (approximate to 49.7%). Significantly, an ultra-high energy density of 327.6 Wh kg(-1) has been achieved using Ni-doped Mn2O3 cathode, which suggests that the synergistic effect of manganese and other transition metal ions provide a promising strategy for future development of ZIBs.