Amine-enriched Graphene Quantum Dots for High-pseudocapacitance Supercapacitors. (1st August 2016)

• Record Type: Journal Article
• Authors: Li, Zhen; Qin, Ping; Wang, Liang; Yang, Chengshuai; Li, Yanfeng; Chen, Zhiwen; Pan, Dengyu; Wu, Minghong
• Is Part Of: Electrochimica acta. Volume 208(2016)
• Page Start: 260
• Page End: 266
• Publication Date: 2016-08-01
• Subjects: graphene quantum dots -- amine-functionalization -- pseudocapacitance -- supercapacitors; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2016.05.030
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Highlights: Amine-enriched porous carbon electrodes have been fabricated by the electrostatic fusion of amine-functionalized single-crystalline GQDs. The carbon films deliver ultrahigh specific capacitance (400–595 F g −1 ) by inducing a high concentration of active amine moieties at edge. GQD supercapacitors offer energy density up to 21.8 Wh kg −1 and retain 90% of the initial capacitance after 10, 000 cyclic voltammetry tests. Amine-enriched GQDs can function as a highly active, solution-processable pseudocapacitive materials applicable to high-performance supercapacitors. Abstract: The applications of carbon-based supercapacitors have been limited by their low energy storage density owing to their limited active storage sites. To overcome this limitation, amine-enriched porous carbon electrodes have been fabricated by the electrostatic fusion of amine-functionalized single-crystalline graphene quantum dots (GQDs) within conductive, vertically ordered TiO2 nanotube arrays as the collectors. The carbon films deliver ultrahigh specific capacitance (400–595 F g −1 ) even beyond the theoretical upper limit of single-layer graphene by inducing a high concentration of active amine moieties at edge. Symmetrical GQD supercapacitors in H2 SO4 electrolyte offer energy density up to 21.8 Wh kg −1 and retain 90% of the initial capacitance after 10000 cyclic voltammetry tests. The results show that amine-enriched GQDs can function as a new kind of highly active, solution-processable, and low-cost pseudocapacitive materials applicable to high-performance supercapacitors.