▎ 摘　　要

Three-dimensional (3D) N, S co-doped graphene hydrogels (NSGHs) were facilely prepared by using thiocarbohydrazide as reducing and doping agents in an aqueous solution. Due to their porous architectures, the as-prepared NSGHs all exhibited high specific capacitance of 123.4, 120.9 and 141.1 F g(-1) at 0.3 A g(-1) for NSGHs-1, NSGHs-2, and NSGHs-5 in KOH electrolyte, respectively. Moreover, their specific capacitance can still be maintained for 723%, 59.4%, and 71.3% even with an increase of the discharging current density of 10 A g-1, respectively. Particularly, the NSGHs-5 based supercapacitor has exhibited excellent electrochemical stability and high degree of reversibility in the long-term cyclic test (90% retention after 4000 cycles). (C) 2015 Elsevier B.V. All rights reserved.