Synthesis of nickel iron sulfides used as electrode materials for supercapacitors

Herein, hydroxides of nickel and iron as well as sulfide of nickel and iron were synthesized by hydrothermal method. Structure, elemental composition and morphology of the samples were characterized by XRD, EDX and SEM. Electrochemical properties of the electrodes were studied by cyclic voltammetry (CV). The results indicate that, Ni/NF, Fe/NF and NiFe/NF show pseudocapacitor behavior while NiS/NF, FeS/NF and NiFeS/NF are likely to be hybrid asymmetric supercapacitors. The synergistic effect of bimetallic nickel and iron ions of the hydroxides and sulfides provides better electrochemical performance of the electrode materials. NiFeS/NF exhibits the highest specific capacitance, 2079 F g-1.