One step hydrothermal synthesis of micro-belts like β-Ni(OH)_2 thin films for supercapacitors

摘要

Present investigation deals with synthesis of micro-belts-like Ni(OH)_2 thin film by the hydrothermal method. Ni(OH)_2 thin films are characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and surface wettability techniques. The XRD and FTIR analyses confirm the formation of β-Ni(OH)_2 thin films. SEM analysis reveals the development of three dimensional growths of randomly distributed interconnected micro-belts. The electrochemical properties of P-Ni(OH)_2 in 2 M KOH electrolyte shows the pseudocapacitive behavior with the specific capacitance of 324 F g~(-1) and capacitive retention of 78% after 500 cycles. The values of specific energy and power are found to be 1.36 Wh kg~(-1) and 50 W kg~(-1), respectively. Additionally, impedance analysis reveals that micro-belt like Ni(OH)_2 provides less electrochemical series resistance.