Electrochemical energy storage performance of electrospun CoMn2O4 nanofibers

Nanofibers of cobalt manganese oxide (CoMn2O4) were grown using an electrospun technique. Structural and microstructural characterizations confirm the formation of phase pure CoMn2O4 with high porosity. The potential application of CoMn2O4 nanofibers as an electrode material for energy storage device was studied using cyclic voltammetry and galvanostatic charge-discharge measurements. A specific capacitance of 121 F/g was observed with enhanced cyclic stability. Furthermore, an energy storage device was fabricated by sandwiching two electrodes separated by an ion transporting layer. The device showed a specific capacitance of 241 mF/cm2 in 3 M NaOH electrolyte. The effect of temperature on the charge storage properties of the device was also investigated for high temperature applications. The device showed about 75% improvement in the charge storage capacity when the temperature was increased from 10 to 70 °C. This research suggests that nanofibers of CoMn2O4 could be used for fabrication of energy storage devices which could operate in a wide temperature range with improved efficiency. •Nanofibers of CoMn2O4 were fabricated using electrospun method.•A specific capacitance of 121 F/g was observed with enhanced cyclic stability.•A supercapacitor device showed a specific capacitance of 241 mF/cm2.•The device showed 75% improvement in charge storage on increasing temperature from 10 to 70 °C.