Carbon nanofiber/graphene composite paper for flexible supercapacitors with high volumetric capacitance

Flexible carbon nanoflber/graphene composite paper (CGCP) was fabricated by vacuum-assisted filtration of aqueous suspension of phenolic nanofibers and graphene oxide, followed by one-step thermal treatment. CGCP displayed a carbon nanoflber/graphene sandwich structure, excellent flexibility, high bulk density (0.59 g cm(-3)) and excellent conductivity (7.6 S cm(-1)), and could be used as supercapacitor electrodes free of binder. Electrochemical measurement results revealed that CGCP had high volumetric capacitance (112 F cm(-3)), much higher than that of traditional electrospun carbon nanofiber paper (30 F cm(-3)). (C) 2015 Elsevier B.V. All rights reserved.