Fabrication of a CuCo2O4/PANI nanocomposite as an advanced electrode for high performance supercapacitors

The main search for faster and more efficient energy storage systems continues to inspire researchers to develop new energy storage materials with ultrahigh performance. Herein, for the first time, we synthesised a CuCo2O4/PANI nanocomposite (NC) by an in situ polymerization route. The physio-chemical properties of the composite were systematically investigated by different spectral and analytical techniques. The electrochemical studies revealed the pseudocapacitive behaviour of the nanocomposite electrode material with a significant capacity value of 1042 C g−1 (289.4 mA h g−1) at a current density of 1 A cm−2 by galvanostatic charge–discharge (GCD) studies. The CuCo2O4/PANI NC exhibited high cycle stability with a capacity retention of 97% and an enhanced coulombic efficiency of 98.5% over 5000 GCD cycles and was noted to be superior to state-of-the-art supercapacitors. In addition, the fabricated symmetric device with CuCo2O4/PANI showed a high energy density of 25.5 W h cm−2 at a power density of 353.7 W cm−2. Moreover, the excellent electrochemical performance of the electrode was attributed to the more abundant electroactive sites and the synergistic effect between CuCo2O4 and PANI during the electrochemical reactions. Thus, the electrochemical properties of the fabricated symmetric supercapacitor device with the CuCo2O4/PANI NC electrode suggested its great potential for commercial applications.