Cu2+ ions inducing the growth of porous Co3O4 nanospheres as high-capacity supercapacitors

Abstract

In this study, porous Co₃O₄ nanospheres were controllably synthesized by applying metal Cu²⁺ ions as structure-inducing agents. The growth of the Co₃O₄ nanostructures was induced by the metal ions without the addition of any surfactants. The porous Co₃O₄ nanospheres were composed of nanosheets. When used as electrode materials in a supercapacitor, the porous Co₃O₄ nanospheres exhibited a much better capacity of 246.7 F g⁻¹ than commercial Co₃O₄ powder at a current density of 0.5 A g⁻¹, maintaining 86% of the initial capacity at a current density of 1 A g⁻¹ after 500 cycles. Such high performance can be attributed to the desirable morphology. The results manifest that porous Co₃O₄ nanospheres composed of nanosheets are promising electrode materials for supercapacitors.