Sustainable Organic Routes to Activated Carbon and Fluoropolymer Membranes for Supercapacitor Applications

The growing demand for flexible, sustainable, and multifunctional energy storage systems has spurred interest in low-cost, biomass-derived materials for next-generation supercapacitors (SCs). This study presents a sustainable organic route to fabricate activated carbon (AC) from jute sticks and a fluoropolymer membrane based on PVDF-HFP, targeting dual applications in piezoelectric and aqueous asymmetric SC configurations. In the self-charging system, jute-derived AC is employed as both electrodes, while the PVDF-HFP membrane functions simultaneously as a separator and a piezoelectric energy harvester. For the asymmetric configuration, the AC serves as the negative electrode, paired with a Ni-based metal–organic framework (Ni-MOF) as the positive electrode, demonstrating the versatility of the biomass-derived carbon in hybrid energy storage systems. The piezoelectric SC achieves an areal capacitance of 72 mF/cm² and effectively converts mechanical energy into electrical energy under applied pressure. Meanwhile, the asymmetric device delivers an areal capacitance of 117 mF/cm², showcasing enhanced charge storage and energy delivery. This dual-application approach highlights the multifunctional potential of jute-derived carbon and fluoropolymer membranes, offering a scalable and environment-friendly pathway for the development of autonomous, self-powered, and portable electronic systems.