High-Performance Asymmetric Supercapacitors Based on the Surfactant/Ionic Liquid Complex Intercalated Reduced Graphene Oxide Composites

Abstract

In this paper, ionic surfactants are employed to intercalate thermally-reduced graphene oxide (TRG). The ionic interaction between the intercalated surfactant and the ionic liquid could lead to the formation of large-sized ionic aggregates and, hence, enlarge the interlayer distance between the TRG sheets. The morphology and vibration modes of these composites were systematically characterized using XRD (X-ray diffraction), SAXS (small-angle X-ray scattering), and FTIR (Fourier transform infrared spectroscopy). An asymmetric supercapacitor, which consisted of a cationic surfactant-intercalated electrode on one side and an anionic surfactant-intercalated electrode on the other, was examined. It was found that, with the increased interlayer distance, the energy density and capacitance of the cells were improved. It seems that the cell with a cationic surfactant as the cathode had the best energy density of 67.8 Wh/kg, which is 4.4-fold higher than that of the TRG cell.

Magnesium Hydroxide Templated Hierarchical Porous Carbon Nanosheets as Electrodes for High-Energy-Density Supercapacitors

“…The energy and power densities are shown in Table S3. These results exceed most carbon-based materials for supercapacitors in ionic liquid electrolytes at high energy densities, such as LaNRTC (55 Wh•kg −1 with 1.7 kW•kg −1 ), 9 YTC (57.4 Wh•kg −1 with 1.724 kW•kg −1 ), 30 thermally reduced graphene (67.8 Wh•kg −1 at 1.58 kW•kg −1 ), 62 graphene nanosheet arrays (74.5 Wh•kg −1 at 0.74 kW•kg −1 ), 63 and CO 2 -activated carbon nanofibers (68 Wh•kg −1 at 1.7 kW• kg −1 ). 64…”