Facile fabrication of coal-derived activated carbon/Co₃O₄ nanocomposites with superior electrochemical performance

Coal-derived activated carbon/Co₃O₄ nanocomposites have been prepared via a facile two-step synthetic strategy. Results indicate that Co₃O₄ nanoparticles possess a uniform distribution on the surface of coal-derived activated carbon. The electrochemical performance of the as-prepared samples had been investigated by cyclic voltammetry and galvanostatic charge/discharge measurement. Results suggest that the nanocomposites exhibit higher specific capacitance than bare Co₃O₄ and coal-derived activated carbon. The superior capacitive performance is further illustrated by electrochemical impedance spectroscopy measurement, which demonstrates that the introduction of coal-derived activated carbon in the nanocomposites can not only improve the electron transfer but also promote the electrolyte penetration.