Activated carbon derived from custard apple shell for efficient supercapacitor

In the present study, activated carbon has been prepared from custard apple (Annona squamosa) shell via chemical activation process, employing zinc chloride as activating agent. Textural properties such as surface morphology, vibratory response, and structural parameters of synthesised activated carbon were studied using SEM, XRD, Raman spectroscopy, surface area and pore size analysis. Electrochemical characteristics of prepared activated carbon were studied by using it as an efficient supercapacitor electrode. The investigation was done in gel polymer electrolyte using conventional electrochemical techniques. High magnitudes of specific capacitance (91.1 F g(-1)), specific energy (12.7 Wh kg(-1)) and specific power (14.7 kW kg(-1)) at current density of 1 mA cm(-1) were observed for assembled supercapacitor cell. Also, assembled supercapacitor cell showed notable cyclic stability, with similar to 90% retention in capacitance value for more than 25 000 cycles. Therefore, synthesised activated carbon may be assumed to be profitable candidate for energy storage applications.