Activated Carbons Derived From Orange Peel Wastes As Electrode Materials In Electrochemical Double Layer Capacitor

As an electrical energy storage device, electrochemical double layer capacitor (EDLC) finds various applications in  electronic products and alternative power source due to its higher energy density, fast discharge/charge time,  safety and long-term operation stability. In this work, orange peel was utilized as the precursor for activated electrodes in EDLC. The surface of the carbon material was treated with the oxidative chemical agents, ZnCl2. The surface morphology, surface  composition, and surface area of the as-prepared carbon materials were observed by scanning electron microscope, X-ray photoelectron spectroscopy and Brunauer–Emmett–Teller Analysis, respectively. Electrochemical characteristics of the carbon  sample were studied by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy measurements in LiPF6 aqueous solution. Compared with the non-activated carbon, activated carbon showed superior capacitive performance. The activation carbon presented a high specific gravimetric capacitance of 180 F g−1. The good electrochemical performance of the activated carbon was attributed to the  high surface area and  larger pore volume.