Phosphorous‐Doped Cocos n ucifera Shell Derived Activated Carbon for Supercapacitor Application

Highly porous activated carbon was synthesized from Cocos nucifera shell through a one‐step KOH‐assisted pyrolysis process at a carbonization temperature of 700 °C. The structural, microstructural, textural, and electrochemical properties of the prepared Cocos nucifera shell‐derived activated carbon (CAC) and phosphorus‐doped activated carbon (P‐CAC) were systematically investigated. The electrochemical performance of both electrode materials was evaluated in a 3 M NaOH electrolyte using a three‐electrode configuration. The CAC and P‐CAC electrodes exhibited excellent capacitive behavior, delivering specific capacitances of 177.4 and 266.5 F g −1 , respectively, at a current density of 1 A g −1 . The enhanced electrochemical performance of the P‐CAC electrode is attributed to the synergistic effect of its hierarchical porous structure, improved surface chemistry, and phosphorus‐induced active sites, which facilitate efficient electrolyte ion transport and charge storage. These findings demonstrate a sustainable and cost‐effective strategy for converting Cocos nucifera shell biomass waste into high‐performance carbon electrode materials, highlighting their potential for application in next‐generation portable and wearable energy storage devices.