Supercapacitors are a kind of efficient and safe energy storage and conversion devices. The development of new - generation supercapacitors that can be used in portable electronic devices and in next - generation vehicles is increasingly demanded. This crucially depends on the discovery of more efficient and cost - effective n ovel materials. Because of their ultrahigh specific surface areas and excellent conductivity , t hree - dimensional (3D) graphene materials hold great promises for supercapacitors. However, the assembly of graphene building blocks into the supercapacitor electrodes with low intrinsic resistance and high ion conductance is still a challenging issue. I n this work, we have undertaken the challenge and used electrochemically generated copper foams (CuF) as an effective template to directly integrate reduced graphene oxide (rGO) 3D networks . This has led to the construction of all - in - one supercapacitor ele ctrodes (3DrGO@CuF) [1] . The overall procedure in clude s two step s : self - assembly of graphene oxide (GO) on Cu F and electrochemical reduction of GO into rGO. The resulting electrodes are capable of delivering a specific capacitance as high as 623 F g - 1 with high cycling stability. Thus, we have shown that h igh specific capacitance can be achieved with 3D graphene nanostructures without any external pseudo - capacitive species doped [2, 3] . The new method is also cost - effective and environmentally friendly