Electrochemical performances of graphene/poly-3,4-dioxyethylenethiophene aerogels as supercapacitor electrode materials

The electrochemical performances of reduced graphene oxide (RGO)/poly-3,4-dioxyethylenethiophene (PEDOT) aerogels as supercapacitor electrode materials were evaluated. The PEDOT was synthesized by oxidative polymerization of 3,4-dioxyethylenethiophene (EDOT). It was doped by nonylphenol polyoxyethylene ether sulfate (NPES) in order to become a flowable material (F-PEDOT) at or near room temperature. Hydrothermal treatment of a mixture of graphene oxide (GO) and F-PEDOT led to reduced graphene oxide (RGO) and dedoped PEDOT (RGO/PEDOT) aerogels which possessed a high specific surface area and a good compressive modulus. When used as a supercapacitor electrode material, it exhibited a high capacitance of 400 F·g⁻¹ at a current density of 0.5 A·g⁻¹, and 234 F·g⁻¹ at a high current density of 20 A·g⁻¹ in the three-electrode test system. It retained almost its initial capacitance over 6000 charge–discharging cycles even at a current density of 10 A·g⁻¹. Moreover, the RGO/PEDOT//RGO asymmetric supercapacitor (ASc) exhibits a maximum energy density of 14.16 W h·kg⁻¹ at a power density of 1.53 kW·kg⁻¹ and displays an acceptable cycle stability with 83.4% of the initial capacitance retention after 8000 charging–discharging cycles at a high rate of 6.25 A·g⁻¹.