jats:titleAbstract</jats:title>jats:pThe utilization of biomass materials that contain abundant carbon–oxygen/nitrogen functional groups as precursors for the synthesis of carbon materials presents a promising approach for energy storage and conversion applications. Porous carbon materials derived from biomass are commonly employed as electric‐double‐layer capacitors in aqueous electrolytes. However, there is a lack of detailed discussion and clarification regarding the kinetics analysis and energy storage mechanisms associated with these materials. This study focuses on the modification of starch powders through the KOH activation process, resulting in the production of porous carbon with tunable nitrogen/oxygen functional groups. The kinetics and energy storage mechanism of this particular material in both acid and alkaline aqueous electrolytes are investigated using in situ attenuated total reflectance‐infrared in a three‐electrode configuration.</jats:p>