Comprehensive Understanding\nof the Impact of Alkaline-Activated\nBamboo-Derived Carbon for Enhancing Supercapacitor Performance

This study explored the potential of steam-treated bamboo-derived\nactivated carbon (AC) for electric double-layer capacitor (EDLC) applications,\nusing KOH, K<sub>2</sub>CO<sub>3</sub>, and Na<sub>2</sub>CO<sub>3</sub> as activation agents to improve electrode materials. The activation\nprocess significantly affected the textural properties: KOH enhanced\nthe surface area and micropore volume, K<sub>2</sub>CO<sub>3</sub> impacted micropores and macropores, and Na<sub>2</sub>CO<sub>3</sub> contributed to mesopores and macropores. TEM and SEM images showed\ndistinct morphologies, with K<sub>2</sub>CO<sub>3</sub> exhibiting\nbubble-like structures and Na<sub>2</sub>CO<sub>3</sub> displaying\na foam-like appearance. X-ray photoelectron spectroscopy analysis\nrevealed specific surface modifications of ACs. Electrochemical performance\nassessments, including charge–discharge behavior, cyclic voltammetry,\nand electrochemical impedance spectroscopy (EIS), demonstrated the\nsuperiority of KOH-AC in EDLC applications due to its high specific\narea and microporosity. The discharge capacitance of EDLC made from\nKOH-AC reached 24 F g<sup>–1</sup> at a current density of\n100 mA g<sup>–1</sup>, while those from K<sub>2</sub>CO<sub>3</sub> and Na<sub>2</sub>CO<sub>3</sub>-AC did not surpass 14 F\ng<sup>–1</sup> under the same conditions. Fitting EIS data\nwith the electrical circuit model partially revealed correlations\nbetween ion diffusion and capacitance values, although further durability\nstudies are needed for practical applications. This investigation\nprovides valuable insights into optimizing steam-treated bamboo-derived\nAC for advanced energy storage systems.