Eco-friendly synthesis of few-layer graphene with high surface area under low temperature for supercapacitors

In this work, few-layered graphene nanosheets (FLG) was prepared through confinement colophony in the 2D galleries of layered double hydroxides (LDH), and followed by transformation of colophony into few-layered graphene at relatively low temperatures (800 °C), as well as a subsequent reflux treatment process. The obtained FLG was tested as supercapacitor electrodes, it exhibits excellent electrochemical performance in terms of specific capacitance (240 F/g at 1 A/g), durability at high current density and long-term operation (95% capacitance retention ratio over 1000 cycles at a current density of 5 A/g). The preparation strategy of lattice orientation/confinement described here provides a convenient, low-cost and eco-friend approach for developing graphene-based energy storage devices.