Examining the Electrochemical Behavior of Low-Temperature Plasma-Treated Activated Carbon from Tea Leaf and Tea Dust for Use as High Efficiency Electrode in Energy Storage Devices

Tea leaves (TL) and tea dust (TD) were pyrolyzed to create activated carbon, which produced porous materials with superior surface properties. To further enhance their performance, the carbon materials were subjected to DC glow discharge plasma treatment, which significantly boosted their surface area and improved their electrochemical behavior. The plasma treatment modifies the surface layers of the nanoparticles, enhancing surface properties like wettability, adhesion, and surface area that were examined through electrochemical, morphological, and structural research. The BET surface area of the tea leaf-derived carbon reached 384 m²/g, while that of the tea dust-derived carbon was 210 m²/g. After plasma treatment, both TL- and TD-based electrode materials exhibited superior surface characteristics and outstanding cyclic stability. Electrochemical tests revealed that the air plasma-treated tea leaf-activated carbon achieved a specific capacitance of 879 F/g, and the air plasma-treated tea dust-activated carbon delivered 510 F/g at a current density of 1.5 mA/g. These findings demonstrate the strong potential of carbonized, activated, and plasma-treated tea waste materials as high-performance electrode materials for energy storage applications.