Effects of Doped Elements on Electrochemical Performance of Ni(OH)2 Materials*

High energy ball milling(HEBM) method was applied to synthesize Ni(OH)2 with different doped elements substitution for Ni2+. The morphology, structure and electrochemical behavior of prepared powders were studied. The results reveal that all the synthesized Ni(OH)2 particles were in sub-micron sizes and greatly agglomerated. Co-, Mg-, Fe- or Mn-doped Ni(OH)2 was of β-phase with 0. 400-0. 500 nm crystal interlayer distance, while Al- and Zn- doped products displayed α-phase with larger crystal interlayer spaces. The electrochemical mechanisms of synthesized Ni(OH)2 electrodes were discussed by EIS spectra. The specific capacity of Co-doped Ni(OH)2 is 245 mA · h · g−1, i.e., 60 mA · h · g−1 higher than that of Al-doped electrode, which has the highest discharging platform of a mid-voltage of 1. 30 V.