Construction of hierarchical structure of Co3O4 electrode based on electrospinning technique for supercapacitor

Highlights: • Hierarchical micro-nanostructure of transition metal oxide was designed. • MOF-derived nanoporous Co₃O₄ was obtained. • Electrospinning technique was used to construct the nanoporous structure. • The Co₃O₄ as supercapacitor electrodes shows high specific capacitance. -- Abstract: The design and synthesis of hierarchical micro-nano structures of transition metal oxides have played an essential role in the supercapacitor field. In this work, in situ three-dimensional construction of nanoporous cobalt oxide (Co₃O₄) has been derived from the metal-organic framework (MOF) distributed evenly in electrospun polyacrylonitrile nanofibers. Due to large specific surface area and network architectures, the as-synthesized Co₃O₄ electrode notably presents a high specific capacitance of 970 F/g at a current density of 1 A/g. Besides, the as-obtained electrode exhibits a high energy density of 54.6 Wh/kg at a power density of 360.6 W/kg and maintains a capacitance retention of 77.5% after 5000 cycles at 6 A/g. Therefore, this method paves a way to produce the nanoporous MOF-derived Co₃O₄ network architecture as advanced electrodes materials, which shows an application potential for the energy storage industry.