DFT-Guided Design of Bioextract-Based Triboelectric Nanogenerators: A Green Pathway to Self-Powered Electronics

Triboelectric nanogenerators (TENGs) have emerged as a promising solution for converting biomechanical energy into electrical power. This study presents a DFT-guided approach to designing bioextract-based polymer composites for sustainable TENG applications. Biosourced polymer (BE) composite films were fabricated via solution casting using natural extracts from lemon, papaya, shikakai, davana, rose, garcinia, reetha, and amla. Morphological and chemical analyses confirmed strong interactions between bioextracts and the polymer matrix, enhancing charge transfer efficiency and mechanical stability. To gain molecular-level insights, density functional theory calculations were performed on PVA–ellagic acid and PVA–limonene complexes by using the B3LYP/6-311G method. The PVA–ellagic acid complex exhibited strong hydrogen bonding and the highest electrophilicity index (3.5787), correlated with enhanced triboelectric performance. In contrast, no hydrogen bonds were observed in the PVA–Limonene complex. BE films were integrated into TENG devices by using aluminum foil electrodes and a PET substrate, demonstrating significant improvements in voltage and current output. Among the tested composites, amla-based BE-TENG achieved the highest performance (130.2 V and 73.0 μA), successfully powering 60 LEDs. The optimized device effectively harvested biomechanical energy for low-power electronics. This study highlights the synergy between computational modeling and experimental validation in developing eco-friendly TENGs. The findings offer a green, high-efficiency pathway for advancing self-powered electronics and sustainable energy solutions.