Interconnected 3 D Network of Graphene-Oxide Nanosheets Decorated with Carbon Dots for High-Performance Supercapacitors.

ABSTRACT

Interconnected 3 D nanosheet networks of reduced graphene oxide decorated with carbon dots (rGO/CDs) are successfully fabricated through a simple one-pot hydrothermal process. The as-prepared rGO/CDs present appropriate 3 D interconnectivity and abundant stable oxygen-containing functional groups, to which we can attribute the excellent electrochemical performance such as high specific capacitance, good rate capability, and great cycling stability. Employed as binder-free electrodes for supercapacitors, the resulting rGO/CDs exhibit excellent long-term cycling stability (ca. 92 % capacitance retention after 20 000 charge/discharge cycles at current density of 10 A g-1 ) as well as a maximum specific capacitance of about 308 F g-1 at current density of 0.5 A g-1 , which is much higher than that of rGO (200 F g-1 ) and CDs (2.2 F g-1 ). This work provides a promising strategy to fabricate graphene-based nanomaterials with greatly boosted electrochemical performances by decoration of with CDs.