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

摘要

Interconnected 3D 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 3D 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 20000 charge/discharge cycles at current density of 10 Ag-1) as well as a maximum specific capacitance of about 308 Fg(-1) at current density of 0.5 Ag-1, which is much higher than that of rGO (200 Fg(-1)) and CDs (2.2 Fg(-1)). This work provides a promising strategy to fabricate graphene-based nanomaterials with greatly boosted electrochemical performances by decoration of with CDs.