Nanopetals assembled copper oxide electrode for supercapacitor using novel 1-(1′-methyl-2′-oxo-propyl)-2,3-dimethylimidazolium chloride ionic liquid as an electrolyte

This paper demonstrates the synthesis of nanopetals-assembled copper oxide thin film by simple and inexpensive hydrothermal method using copper sulfate hexahydrate as precursor. The structural analysis from X-ray diffraction pattern showed formation of monoclinic crystal structure. Surface morphological studies by scanning electron micrograph revealed formation of uniform and crack free bunches of nanopetals. Electrochemical behavior of copper oxide was investigated at different concentrations of novel 1-(1׳-methyl-2׳-oxo-propyl)-2,3-dimethylimidazolium chloride ionic liquid as an electrolyte using cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy. The results demonstrated that, the nanopetal assembled copper oxide exhibited maximum specific capacitance of 133 F g−1 in 0.2 M ionic liquid.