LAUSR

Abstract In this work, the CoFe2O4/CNTs composite was successfully synthesized by one-pot hydrothermal method. The CoFe2O4/CNTs composite was applied as supercapacitor's electrode and exhibited good electrochemical properties with high specific capacitance (1240 F/g at current density of 0.5 A/g and 941 F/g at 10 A/g). Moreover, the CoFe2O4/CNTs composite asymmetric supercapacitor with CoFe2O4/CNTs composite and active carbon (AC) as positive and negative electrodes, respectively, delivered high energy density of 30.4 W h/kg at power density of 400 W/kg. The energy density could still maintain 12.4 W h/kg at a high power density of 3986 W/kg. More importantly, the specific capacitance of CoFe2O4/CNTs//AC asymmetric supercapacitor device retained 85.6% of initial capacitance after 1000 cycles at current density of 2 A/g. The results suggest that the synthesized CoFe2O4/CNTs composite was a promising candidate for application to supercapacitors electrodes.