Coralloid and hierarchical Co3O4 nanostructures used as supercapacitors with good cycling stability

Coralloid and hierarchical Co3O4 nanostructures were synthesized by a facile two-step approach composed of room temperature solution-phase synthesis without any surfactant and calcination of precursor. Owing to the unique structural features, the capacitance of Co3O4 could reach up to 591 F g−1 at a current density of 0.5 A g−1. Especially the cycling stability remained about 97 % after 2000 cycles at a current density of 1 A g−1. These results demonstrated that the coralloid and hierarchical Co3O4 were excellent candidates for electrochemical supercapacitor devices.