▎ 摘 要
In present work, three-dimensional (3D) reduced graphene hydrogels (RGHs) are prepared through an efficient and facile strategy by employing three types of carbohydrates (glucose, fructose and sucrose) as reducing agents in aqueous solution of graphene oxide (GO) with ammonia. The formation of RGHs could be confirmed by X-ray powder diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). The structures and porosity were characterized by field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM) and N-2 sorption experiments. Benefiting from the abundant porous architectures as fast ionic channels for electrochemical energy storage, the prepared RGHs exhibited a high specific capacitance up to 153.5, 145.0 and 150.3 F g(-1) at 0.3 A g(-1) for FRGHs (fructose), GRGHs (glucose) and SRGHs (sucrose), which can be maintained for 61.4, 61.5 and 46.9% as the discharging current density was increased up to 20 A g-1. Moreover, it also showed that the electrode based on RGHs has good electrochemical stability and high degree of reversibility in the charge/discharge cycling test.