Preparation and electrochemical performance of orange peel based-activated carbons activated by different activators

The orange peel based-activated carbons were prepared via hydrolysis and chemical activation, in which KOH, H3PO4 and ZnCl2 were used as activators, respectively. Textural characterization (XRD, SEM and N-2 adsorptiondesorption) and electrochemical tests (CV, GCD, EIS and the cycle life) were carried out to reveal the structure-property relationship of the activated carbon samples. The results showed that the activated carbon activated by H3PO4 (AC-H3PO4) presents the highest specific surface area (2209.7 m(2)/g) and pore volume (1.2374 cm(3)/g) compared with the others. Correspondingly, the AC-H3PO4 electrode also showed the highest specific capacitance of 240 F/g and 97% capacitance retention after 10,000 charge and discharge cycles. Moreover, the effect of the larger-size micropores (1.3-1.8 nm) of AC-H3PO4 sample and macropores of AC-KOH sample on the electrochemical performance of the carbon materials was discussed.