One pot hydrothermal growth of hierarchical nanostructured Ni3S2 on Ni foam for supercapacitor application

Abstract

Abstract In this study, we demonstrated the formation of nanoarchitectures of nest like Ni3S2 grown directly on Ni foam by a one pot hydrothermal route and used it as a binder free electrode for high performance supercapacitors. The formation of Ni3S2 on the Ni foam is confirmed by the X-ray diffraction analysis. Field emission scanning electron microscope study revealed the formation of nest like Ni3S2 grown on the Ni foam has been obtained by the hydrothermal method. A plausible mechanism for the formation of Ni3S2 phase is discussed. The electrochemical properties of the as prepared Ni3S2/Ni electrodes are studied using cyclic voltammetry (CV), galvanostatic charge–discharge analysis and electrochemical impedance spectroscopy (EIS) studies. The CV study revealed the presence of redox peaks suggesting the pseudocapacitive nature of the prepared Ni3S2/Ni electrode. Galvanostatic charge–discharge analysis showed a maximum specific capacitance of 1293 F/g was achieved for the Ni3S2/Ni electrodes at a constant current density of about 5 mA/cm2. Further, EIS results (such as Nyquist and Bode plots) confirmed the pseudocapacitive nature of the Ni3S2/Ni electrode. The experimental results suggested the design of hierarchical nanostructures of Ni3S2 grown on Ni foam as a binder free electrode material will be an ideal candidate for supercapacitor applications.