Pulse electrochemical synthesis of capsule-like nanostructures of Co3O4 and investigation of their capacitive performance

A novel nanostructure of Co3O4 was prepared via pulse cathodic deposition followed by heat-treatment. The prepared sample was characterized by XRD, IR, SEM and TEM techniques. The results revealed that the prepared sample is composed of crystalline cubic spinel Co3O4 with capsule-like morphology. The supercapacitive investigation by cyclic voltammetry and charge–discharge tests displayed that the Co3O4 nanocapsules have high electrochemical contribution into the redox reactions where they delivered high capacitance of 454.7 F gsingle bond1 at the applied discharge current density of 2 A gsingle bond1, and an excellent long-term cycling stability (94.5%) capacity retention after 500 cycling at current density of 2 A gsingle bond1. These abilities of Co3O4 nanocapsules suggest their potential application in the electrochemical supercapacitors.