A facial strategy to synthesize Co3O4 hollow tube nanoarray with enhanced supercapacitive performance

Abstract Co3O4 as an electrode material has been widely used for energy storage. However, it has low capacity and is generally associated with poor cycle life and stability. We designed the Co3O4 hollow tube arrays on Ni foam though a facial strategy based on the ZnO sacrificial template method. Benefit from the unique hollow structure advantage and the low resistance brought by the use of self-supporting method without binder. Compared to Co3O4 directly grown on a substrate, the as-prepared hollow Co3O4 structure exhibits large electrochemical capacity of 748.1 C g−1 at 1 A g−1, the result is larger than that of pure Co3O4 directly growing on the substrate without adding Zn2+ as the template. Furthermore, a hybrid supercapacitor device Zn@Co//AC reaches the specific energy of 60.91 Wh kg−1 under the specific power of 450 W kg−1.