Nickel ions doped MnO₂ to effectuate the outstanding performance of cathodes for aqueous zinc-ion batteries

Abstract Nickel-doped MnO 2 (Ni-MnO 2 ) material has been successfully manufactured using an improvised hydrothermal method. Characterization and electrochemical tests demonstrate that nickel ions are incorporated into Ni-MnO 2 ; this substantially increases both the performances of the electrode materials in terms of electrical conductivity and the rate performance of MnO 2 . Therefore, when the experimental conditions were extended to 1 A g −1 , measurements from the long-cycle test show that the specific capacity of Ni-MnO 2 has been maintained at the level of 56.8 mAh g −1 after 500 cycles, which is even as high as 60% capacity retention, much superior to the 34.2% capacity retention of MnO 2 . These findings give promising insights for enhancing the stability of MnO 2 in AZIBs.