Carbon nanotubes/reduced graphene oxide composites as electrode materials for supercapacitors

Carbon nanotubes (CNTs)/graphene composite fiber has become an encouraging material for the construction of wearable supercapacitors due to its excellent performance. CNTs/reduced graphene oxide (RGO) composite fibers with large specific surface area were prepared by CVD method using alginic acid (Alg)/graphene oxide (GO) fibers with Ni ions uniformly loaded, the structure and electrochemical performance were investigated. Flexible Alg/GO fiber with diameters of 45 to 125 mu m were fabricated by dry-jet wet spinning or wet spinning. CNTs/RGO composite fibers with hollow CNTs in diameters of 150 to 500 nm, which were fabricated by CVD method using Ni as catalyst, exhibited a specific surface area of 366.98 m(2) g(-1). Electrochemical analysts indicated that the fibers exhibited excellent specific capacitance of 267.8 F g(-1) for double-layer capacitors and 49.3 F g(-1) for symmetrical capacitors, which implied that the porous composite fiber with large specific surface area is a potential electrode material for fabricating flexible energy storage device.