Modified Structural, Optical and Electrochemical Properties of Nickel Sulphide for Superior Supercapacitor Electrode

Nickel sulphide is one of the proficient electrode materials for supercapacitors. Current abstract portrays about thin film deposition of nickel sulphide by simple chemical route and further improvement in structural, morphological, optical and electrochemical properties is obtained by heat treatment.

Comparative analysis of as-deposited and annealed nickel sulphide thin film electrodes is characterized via XRD, FESEM, UV and electrochemical testing. X-ray diffraction shows amorphous to polycrystalline transformation and renders flakes like morphology for both as deposited and annealed samples. Moreover, optical band gap decreases after annealing from 2.67 to 2.36 eV reveals, red shift as well as improved in crystallinity of sample. This ritual effect results in boosting of electrochemical performance of nickel sulphide electrode by lowering impedance i.e. charge transfer resistance. Thus, annealing process offers more accessible electrode-electrolyte interaction towards flake like morphology and causes increase in capacitance.Nickle sulphide electrode shows specific capacitance value of 655 Fg⁻¹ at 10 mVs^-1 scan rate and 641 Fg^-1 at 1.0 mAg^-1 current density in 1M KOH aqueous electrolyte with ~83% stability for 1000 cycles. Hence, improvement in the structural, optical, and electrochemical properties and performance for nickel sulphide electrode is suitably attained and employed for supercapacitor application by Simple chemical method