2-Amino-3-chloro-1,4-naphthoquinone covalently anchored on reduced graphene oxide as all-carbon energy storage material

Further increasing the energy density of supercapacitors without reducing their high power density and stability remains a challenge. Organic quinone molecules have demonstrated potential in electrochemical energy storage on account of their excellent electrochemical activity and reversibility. Herein, 2-amino-3-chloro-1,4-naphthoquinone (2-NTQ) is covalently connected to the reduced graphene oxide (RGO) to obtain a new all-carbon electrode material (2-NTQ-RGO). The 2-NTQ-RGO composite exhibits excellent capacitance performance by incorporating the merits of the 2-NTQ molecules and RGO. The optimized 2-NTQ-RGO possesses a high specific capacitance of 453 F g(-1) at 1 A g(-1) and displays good cycle stability (83% of the initial after 8000 cycles) in 1 M H2SO4 electrolyte. Moreover, two asymmetric supercapacitors are assembled for the purpose of investigating the influence of the electrode materials matching on the performance of the capacitor. With the same positive material, the 2-NTQ-RGO//DQ-RGO can achieve an energy density of 23.4 Wh kg(- 1) and a power density of 900 W kg( -1). Two ASC devices in series can light up in the shape of a butterfly consisting of 71 light-emitting diodes (LEDs). In contrast, the energy density of the 2-NTQ-RGO//AC is only 16.7 Wh kg(- 1) (812 W kg( -1)). The covalent grafting offers a new promising and effective method for the preparation of green all-carbon energy storage materials.

Automated summary

This study presents the covalent connection of 2-amino-3-chloro-1,4-naphthoquinone (2-NTQ) to reduced graphene oxide (RGO) to obtain a new all-carbon electrode material (2-NTQ-RGO). The composite exhibits excellent capacitance performance by combining the advantages of the 2-NTQ molecules and RGO. Furthermore, the matching of electrode materials influences the performance of the supercapacitor.