Investigation on copper cobaltite (CuCo2O4) and its composite with activated carbon (AC) for supercapacitor applications

Abstract

Energy storing devices plays a major role in the development of technology. We synthesized carbon-based nanocomposites through a physical method and CuCo₂O₄ nanocomposites through a sol–gel technique calcined at 600 °C. From X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) confirmed the formation of CuCo₂O₄ nanocomposites which also shows some impurity phase of CuO nanoparticle. The average crystalline size found to be 45 nm. According to optical absorption analysis, the particles show maximum absorption in 256 nm and 369 nm in the UV region, while copper cobaltite doped with activated carbon (AC) shows broad absorption compared with copper cobaltite alone. Morphology studies shows agglomerate image in AC composites and hexagonal structures was formed in CuCo₂O₄ nanoparticles with average particle size of 100 nm. Atomic and weight percentages were recorded using energy dispersive X-ray analysis (EDAX). A good specific capacitance can be found from CV analysis, using electrochemical impedance spectroscopy (EIS), nanoparticles are shown to have different interface properties at the surface of electrodes. Using CuCo₂O₄ and its composite as positive and negative electrodes in cyclic voltammetry (CV) studies shows excellent electrochemical properties. In addition, CuCo₂O₄ with activated carbon is promising as a low-cost and good supercapacitor material.