▎ 摘　　要

2,6-Diaminoanthraquinone (DQ) molecules were covalently modified onto the surface of graphene (GO)viaa nucleophilic displacement reaction between the epoxy groups on the surface of GO and the -NH(2)groups of DQ molecules in the presence of ammonia to form a composite material (labeled as DQ-RGO). The rapid reversible faradaic reactions of DQ molecules are realized by means of the good conductivity of graphene. Therefore, the DQ-RGO composite material can combine the Faraday pseudocapacitance of DQ with the double-layer capacitance of graphene, thus displaying outstanding electrochemical performance in acidic electrolyte solution, including a high specific capacitance (332 F g(-1) at 1 A g(-1)), excellent rate capability (the capacitance retention rate is 72.9% at 50 A g(-1)) and good cycling stability (maintaining 81.8% of the initial capacitance after 5000 cycles). Meanwhile, a thionine-functionalized graphene hydrogel (Th-GH) was also preparedviaa non-covalent strategy. Finally, the DQ-RGO composite acted as the negative electrode and Th-GH acted as the positive electrode to construct an asymmetric supercapacitor (ASC). The ASC exhibited an energy density of 14.2 W h kg(-1) along with a power density of 0.763 kW kg(-1) and long cycling durability (maintaining 80% of the initial capacitance after 8000 cycles at 5 A g(-1)). More importantly, two such devices in series successfully illuminated 16 red light-emitting diodes (LEDs), demonstrating its outstanding energy storage performance. This work can provide ideas for the construction of green, all-carbon and excellent electrochemical performance devices.