Facile and Eco-Friendly Synthesis of Finger-Like Co(3)O(4) Nanorods for Electrochemical Energy Storage

Co(3)O(4) nanorods were prepared by a facile hydrothermal method. Eco-friendly deionized water rather than organic solvent was used as the hydrothermal media. The as-prepared Co(3)O(4) nanorods are composed of many nanoparticles of 30–50 nm in diameter, forming a finger-like morphology. The Co(3)O(4) electrode shows a specific capacitance of 265 F g(−1) at 2 mV s(−1) in a supercapacitor and delivers an initial specific discharge capacity as high as 1171 mAh g(−1) at a current density of 50 mA g(−1) in a lithium ion battery. Excellent cycling stability and electrochemical reversibility of the Co(3)O(4) electrode were also obtained.