Enhanced electrocatalytic activity of the solvothermally synthesized Mesoporous Rhombohedral nickel sulphide

In the present work, Mesoporous Rhombohedral β-NiS (Nickel Sulphide) was synthesized by a solvothermal route using thiourea as Sulphur source. Rietveld refinement confirms the single phase formation of Rhombohedral β-NiS. Reaction temperature affects the electro-catalytic, optical and morphology of the synthesized β-NiS nanoparticles. 1-D nano-rods and cluster beans like structures are observed in FESEM images. At lower temperature, energy band gap of the synthesized β-NiS nanoparticles is found to be 2.75 eV. Carbonaceous free electrodes were used for electrocatalytic studies in 1 M aqueous LiOH electrolyte. Electrocatalytic activity of β-NiS nanoparticles were studied by cyclic voltammetry technique and electrochemical impedance spectroscopy. During the analysis of cyclic voltammetry technique it was found that the synthesized β-NiS electrode showed maximum areal capacitance 12.02 F cm−2 with 83% cyclic stability over 1000 cyclic voltammetry cycles.