Nanosheets based mixed structure CuCo2O4 hydrothermally grown on Ni foam applied as binder-free supercapacitor electrodes

Abstract

• Nanosheets mixed structure CuCo 2 O 4 on Ni foam was synthesized by a facile hydrothermal reaction. • Nanosheets mixed structure CuCo 2 O 4 show the superior electrochemical performances. • CuCo 2 O 4 nanosheets exhibit specific capacitance of 1595 F g −1 at 1 A g −1 and good cycling stability. CuCo 2 O 4 has been successfully hydrothermally grown on Ni foam. The morphology of the sample are observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The product has a unique morphology based on nanosheets which can self-assembly into two main structure. The electrode exhibits good electrochemical performance in supercapacitor application. The specific capacitance is 1595 F g −1 at 1 A g −1 , and specific capacitance keeps 85.1% after 4600 cycles. Such performance may be responsible for some factors. Three-dimensional Ni foam can be regarded as a conductive skeleton and firm substrate. It can further enhance the conductivity by not using binders. The unique mixed structure can provide more exchange between electrode and electrolyte. Both faster electron transmission and shorter ion diffusion path facilitate the redox reactions which can improve the electrochemical performance. The results indicate the nanosheet based mixed structure CuCo 2 O 4 grown on Ni foam have a promising future as supercapacitor electrodes. CuCo 2 O 4 nanosheets grown on Ni foam applied as binder-free electrode of supercapacitor shows an impressive enhancement of the performance including the areal capacitance and cycling stability.