Self-assembled N/S codoped flexible graphene paper for high performance energy storage and oxygen reduction reaction

A novel flexible three-dimensional (3D)

architecture of nitrogen and sulfur codoped graphene has

been successfully synthesized via thermal treatment of a liquid

crystalline graphene oxide−doping agent composition, followed

by a soft self-assembly approach. The high temperature

process turns the layer-by-layer assembly into a high surface

area macro- and nanoporous free-standing material with

different atomic configurations of graphene. The interconnected

3D network exhibits excellent charge capacitive performance of 305 F g−1 (at 100 mV s−1), an unprecedented volumetric

capacitance of 188 F cm−3 (at 1 A g−1), and outstanding energy density of 28.44 Wh kg−1 as well as cycle life of 10 000 cycles as a

free-standing electrode for an aqueous electrolyte, symmetric supercapacitor device. Moreover, the resulting nitrogen/sulfur

doped graphene architecture shows good electrocatalytic performance, long durability, and high selectivity when they are used as

metal-free catalyst for the oxygen reduction reaction. This study demonstrates an efficient approach for the development of

multifunctional as well as flexible 3D architectures for a series of heteroatom-doped graphene frameworks for modern energy

storage as well as energy source applications.