<p>This study presents a novel approach to the sustainable synthesis of highly porous activated carbon from tender coconut husk – an underutilized, carbon-rich agricultural waste with a naturally slow decomposition rate and high lignocellulosic content, which causes severe environmental pollution. For the first time, tender coconut husk is explored as a potential carbon precursor for triboelectric nanogenerator (TENG) applications. The sample material was carbonized and activated with different chemical activating agents, such as potassium hydroxide, phosphoric acid, and zinc chloride, with a 2:1 impregnation ratio to explore their influence on developing porous carbon structures. The pore structure, elemental composition, and surface chemistry were analyzed using scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), energy-dispersive X-ray spectrometry (EDX), X-ray diffraction spectroscopy (XRD), and Fourier-transform infrared spectroscopy (FTIR). These studies indicated the formation of highly porous activated carbon with various surface functional groups attached. Furthermore, the synthesized activated carbon was used as an additive in polyvinyl alcohol to enhance its triboelectric performance, thereby expanding the application of activated carbon to a new area. The power density produced with the activated carbon-modified polymeric triboelectric layer was approximately 6.5 times higher than that obtained with the polyvinyl alcohol layer, demonstrating a significant advancement in energy harvesting capabilities. This research investigates a cost-effective and eco-friendly method for valorizing tender coconut husk into high-performance activated carbon, highlighting its role as a sustainable additive in polymer-based TENGs, and contributes to the development of next-generation sustainable energy technologies.</p>