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

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.