Surfactant-modified chemically reduced graphene oxide for electrochemical supercapacitors

Abstract

An easy method to synthesize surfactant-modified graphene for a supercapacitor is demonstrated through the intercalation of graphene oxide (GO) with a triblock copolymer Pluronic F127 (F127). A rationalized, reduced GO-F127 is obtained by hydrothermal and thermal annealing-driven structural reconstruction. The F127 successfully intercalates into the GO layers and facilitates the stabilization of the single-layer or few-layer structure of graphene sheets during the reduction process. An increased surface area of 696 m² g⁻¹ is achieved in the surfactant-modified graphene, which is about three times higher than that of pristine graphene (200 m² g⁻¹). The electrocapacitive behaviors of the resultant composites are systematically investigated by cyclic voltammetry and galvanostatic charge–discharge techniques. The rGO-F127 sample thermal-treated at 400 °C delivers a maximum specific capacitance of 210 F g⁻¹ at a scanning rate of 1 mV s⁻¹ in 6 M KOH electrolyte and has an excellent cycling stability, retaining over 95.6% of the initial capacity after 1000 cycles.