Chemical synthesis of cobalt oxide thin film electrode for supercapacitor application

Cobalt oxide thin film electrode was grown on copper substrate from an aqueous alkaline bath containing cobalt chloride as a cobalt source by adopting simple and inexpensive chemical deposition method and characterized for structural and morphological studies. The supercapacitive properties of cobalt oxide electrode were studied in aqueous KOH electrolyte solution. The effect of electrolyte concentration on specific capacitance and the stability of cobalt oxide electrode were studied. The highest specific capacitance achieved with cobalt oxide films was 118 F g−1. The specific energy (E), specific power (P) and coulomb efficiency (η%) were 5.8 Wh kg−1, 0.33 kW kg−1 and 93.44%, respectively.