Copper oxide/mesoporous carbon nanocomposite synthesis, morphology and electrochemical properties for gel polymer-based asymmetric supercapacitors

A novel nanocomposite was synthesized by combining copper oxide with mesoporous carbon (CuO/MPC) and tested for potential applications as a supercapacitor electrode. Due to the presence of highly conductive carbon, this CuO/MPC nanocomposite is expected to provide additional pathways and more electro-active sites for ion diffusion than a metal oxide electrode alone. Indeed, the CuO/MPC electrode exhibits superior supercapacitive features including the specific capacitance of 616 F g(-1) at a current density of 1 A g(-1), and better rate capacity and cyclic stability. Further, an asymmetric supercapacitor cell was assembled using the CuO/MPC composite with activated carbon as electrodes, and gel polymer (PVA-KOH) as electrolyte. This asymmetric device displays higher electrochemical performance with an energy density of 26.6 W h kg(-1) and a power density of 438 W kg(-1). This device holds 69% of initial capacitance after 5000 cycles. These results provide a foundation for innovation of next generation energy storage device to fulfil the future demand.