Fabrication of NiO@Co3O4 core/shell nanofibres for high-performance supercapacitors

NiO@Co3O4 core/shell nanofibres (NiO@Co3O4 NFs) as a promising supercapacitors electrode material were synthesized by a facile co-electrospinning method and heat treatment. The NiO core is about 125 nm in diameter and the Co3O4 shell has a thickness of ~80 nm. The electrochemical properties of NiO@Co3O4 NFs in 6 M KOH aqueous electrolyte are investigated. Compared with NiO (222 F g−1, 1 A g−1) and Co3O4 (284 F g−1, 1 A g−1) nanofibres, NiO@Co3O4 NFs electrode exhibits higher specific capacitance (437 F g−1, 1 A g−1), as well as good cycling stability (82.9% retention after 1000 cycles at 5 A g−1). The enhanced electrochemical performances can be attributed to the uniform core/shell fibre nanostructures. These results suggest that such NiO@Co3O4 NFs would be promising electrodes for supercapacitors.