Supramolecule-Inspired\nFabrication of Carbon Nanoparticles In Situ Anchored Graphene Nanosheets\nMaterial for High-Performance Supercapacitors

Abstract

The remarkable electrochemical\nperformance of graphene-based materials has drawn a tremendous amount\nof attention for their application in supercapacitors. Inspired by\nsupramolecular chemistry, the supramolecular hydrogel is prepared\nby linking β-cyclodextrin to graphene oxide (GO). The carbon\nnanoparticles-anchored graphene nanosheets are then assembled after\nthe hydrothermal reduction and carbonization of the supramolecular\nhydrogels; here, the β-cyclodextrin is carbonized to carbon\nnanoparticles that are uniformly anchored on the graphene nanosheets.\nTransmission electron microscopy reveals that carbon nanoparticles\nwith several nanometers are uniformly anchored on both sides of graphene\nnanosheets, and X-ray diffraction spectra demonstrate that the interlayer\nspacing of graphene is enlarged due to the anchored nanoparticles\namong the graphene nanosheets. The as-prepared carbon nanoparticles-anchored\ngraphene nanosheets material (C/r-GO-1:3) possesses a high specific\ncapacitance (310.8 F g^–1, 0.5 A g^–1), superior rate capability (242.5 F g^–1, 10 A\ng^–1), and excellent cycle stability (almost 100%\nafter 10 000 cycles, at the scan rate of 50 mV s^–1). The outstanding electrochemical performance of the resulting C/r-GO-1:3\nis mainly attributed to (i) the presence of the carbon nanoparticles,\n(ii) the enlarged interlayer spacing of the graphene sheets, and (iii)\nthe accelerated ion transport rates toward the interior of the electrode\nmaterial. The supramolecule-inspired approach for the synthesis of\nhigh-performance carbon nanoparticles-modified graphene sheets material\nis promising for future application in graphene-based energy storage\ndevices.