High performance supercapacitors using selenium partially reduced Co3O4 on carbon cloth electrode with 3D interconnected architecture nanowires

Abstract

The electrodes with high conductivity, large specific surface area and homogeneous pore size distribution are greatly desirable for supercapacitors applications. Herein, a hydrothermal and subsequent annealing approach was adopted to fabricate 3D interconnected nanowires architecture of selenium partially reduced spinel Co3O4 grew on the carbon cloth (COS@CC). The binder-free COS@CC electrode displays excellent specific capacitance, 1046.9 C g−1 at 1 A g−1, superior rate capability, 51.6% capacitance retention and superior cyclic stability, 92.0% capacitance retention after 15,000 cycles. These electrochemical performances were found to be better than that of the Co3O4@CC electrode. The enhanced electrochemical performance was ascribed to the fact that 3D interconnected architecture nanowires could shorten the ion transfer distance and heighten the rate of the redox reaction. In addition, increased specific surface area and homogeneous mesopore size distribution could assist effective diffusion and transfer of OH– between electrodes and electrolyte. The enhancement of conductivity, which is caused by the selenium partial reduction and more oxygen vacancies in the structure, facilitates electrons transfer and consequently improves the electrochemical properties of supercapacitors. These remarkable electrochemical performances indicate that the CSO@CC can be employed for developing high-energy and power-density supercapacitors.