Supercapacitors Based on Resveratrol/Reduced Graphene Oxide Composites

Resveratrol (Res), which is a redox activation reagent, is a remarkably cheap and high-energy pseudocapacitive material because of possessing fast and reversible redox reactivity. Herein, we investigated Res as an organic compound with oxidation–reduction activity. One of the effective strategies to address these drawbacks, which are high costs, unfriendly environment, and short redox reactivity, is to composite Res with three-dimensional graphene structures. The obtained composites of Res/reduced graphene oxide (rGO) showed an abundance of active sites and a high specific capacitance. Res/rGO composites with different amounts of Res and GO were prepared using a one-step hydrothermal method. Electrochemical performance test results showed that the addition of Res resulted in a higher specific capacitance of the composite compared with that of rGO, reaching 588 F g–1 in 6 mol L–1 potassium hydroxide when the mass ratio of GO-to-Res was 3:1. In the specific capacitance at a current density of 2 A g–1, cycling stability was good, and the initial capacitance was 88.8% after 10,000 cycles. Adsorption energies and density of states of Res on graphene surfaces are calculated to further understand the charge storage mechanism by density functional theory. The calculation results show that Res plays a crucial role in excellent electrochemical performance.