One-pot hydrothermal synthesis, characterization and electrochemical properties of CuS nanoparticles towards supercapacitor applications

In this article, we have investigated the electrochemical properties of CuS nanoparticles for supercapacitor applications. The CuS nanoparticles are prepared by a facile one-pot hydrothermal approach using copper nitrate and thiourea as starting materials. The x-ray diffraction study revealed the formation of covellite CuS. The field-emission scanning electron microscope studies suggested the formation of cubic shaped CuS nanoparticles. The electrochemical studies such as cyclic voltammetry, galvanostatic charge-discharge analysis and electrochemical impedance spectroscopy confirmed the pseudocapacitive nature of the CuS electrodes. The CuS electrode shows a specific capacitance of about 101.34 F g⁻¹ from the cyclic voltammetry at a scan rate of 5 mV s⁻¹. The electrochemical impedance spectra analyzed using Nyquist plot confirmed the pseudocapacitive behavior of the CuS electrodes. (paper)