All-carbon flexible supercapacitors based on electrophoretic deposition of graphene quantum dots on carbon cloth

• Published in: Journal of power sources Vol. 438; p. 227009
• Main Authors: Tjandra, Ricky, Liu, Wenwen, Zhang, Maiwen, Yu, Aiping
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 31.10.2019
• Subjects: EDLC; Energy storage; Flexible supercapacitor; Graphene; Quantum dots; Flexible supercapacitor; Graphene; Quantum dots; EDLC; Energy storage
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2019.227009

In this work, a flexible, free-standing supercapacitor electrode fabricated using a combination of Graphene Quantum Dots (GQD) and carbon cloth. The GQD was synthesized using a simple peroxide-assisted hydrothermal method and was electrodeposited on carbon cloth to ensure intimate contact. The presence of GQD on the surface of the carbon cloth greatly enhanced its capacitance, resulting in a flexible EDLC electrode with an areal capacitance of 70 mF cm−2 at a scan rate of 50 mV s−1 even with a negligible mass loading. We have also demonstrated a fully-flexible symmetric full-cell fabricated using the GQD/carbon cloth composite with a high-rate capability, showing a rectangular CV curve even at a high scan rate of 1 V s−1 and capacitance of 24 mF cm−2 at a scan rate of 50 mV s−1 when flexed and un-flexed. [Display omitted] •Graphene quantum dots can be made easily by peroxide assisted hydrothermal reaction.•Graphene quantum dots significantly boosts capacitance of carbon cloth.•Graphene quantum dot/carbon cloth composite electrodes have remarkable rate performance.•Flexible supercapacitor made from graphene quantum dots and carbon cloth have high energy density.