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 g(-1) at the applied discharge current density of 2 A g(-1), and an excellent long-term cycling stability (94.5%) capacity retention after 500 cycling at current density of 2 A g(-1). These abilities of Co3O4 nanocapsules suggest their potential application in the electrochemical supercapacitors. (C) 2013 Elsevier B. V. All rights reserved.