Gelatin-Based Microporous Carbon Nanosheets as High Performance Supercapacitor Electrodes

Microporous carbons nanosheets with controllable thicknesses were synthesized using gelatin biomass as both carbon and nitrogen precursors and graphene oxide (GO) without any auxiliary reagent. The pore structures, surface chemical compositions, and morphology of the microporous carbon material were analyzed and characterized by nitrogen adsorption isotherms, thermogravimetric analysis, Fourier transform infrared spectrum, X-ray photoelectron energy spectrum, and transmission electron microscope and scanning electron microscope images. The carbon nanosheets showed average thicknesses from 10 ± 4 to 30 ± 8 nm with tuning mass ratios of gelatin to GO from 20/1 to 100/1. The microporous carbon nanosheets exhibited high specific capacitance and excellent rate capability with a capacitance retention of 76% at 20 A/g in a 6 mol/L KOH aqueous electrolyte because of the shorter diffusion distance, large surface area, and excellent electrical conductivity.