Capacitance Performance of Nanostructured CoNi2S4 with Different Morphology Grown on Carbon Cloth for Supercapacitors

Nanostructured CoNi2S4 materials with different morphologies were successfully grown on carbon cloth through a facile precursor transformation method by adjusting the anions in nickel cobalt salts. The resulting samples were characterized by XRD, EDS, FESEM, and TEM and were found to display different morphologies. Their electrochemical performance was investigated by means of cyclic voltammetry (CV), galvanostatic charge-discharge, electrochemical impedance spectroscopy (EIS), and cycle life. The as-obtained CoNi2S4 sample with NO3- as the anion in the nickel cobalt salt displayed an ultrahigh specific capacitance of 2714Fg(-1) at 1Ag(-1) and excellent rate capability (64.8% capacity retention at 20Ag(-1)). However, the as-obtained CoNi2S4 samples with SO42- and Cl- as the anions in the precursors displayed a limited specific capacitance of only 1750 and 1334Fg(-1), respectively. Besides, they also displayed different performances in the cycle life test. The study indicates that the as-obtained CoNi2S4 grown on carbon cloth prepared with NO3- as the anion will be a promising electrode material for supercapacitors.