Synthesis of ZnO/activated carbon with high surface area for supercapacitor electrodes

This research demonstrated that zinc oxide (ZnO) and activated carbon with specific surface area were prepared and applied as supercapacitor electrodes. The composites of ZnO and activated carbon including Chlorella vulgaris and asphaltene were synthesized through in-situ reaction. Zinc precursor solution was mixed with activated carbon by precipitation method depending on the concentration and type of precursor. These composites were well grown on the surface of activated carbon which not only exhibited diverse morphology but also affected the specific surface area. The specific capacitance of ZnO/activated carbon composites reached a maximum value of 155 F/g at 0.5 A/g within a potential window of −1.0 to 0 V in Na2SO4, and both activated carbon derived from Chlorella vulgaris and asphaltene exhibited excellent cycle retention during 1000 charging/discharging cycles. The excellent electrochemical performances showed the ZnO/activated carbon composites to be a high-performance material for supercapacitor electrodes.