Hardwood-derived lignin as a tribo-positive filler in electrospun PVDF nanofibers for efficient triboelectric energy harvesting

Authors: DEURI, DEEPAK JYOTI - Nowgong College; MAHANTA, JIWAJYOTI - Indian Institute Of Technology; SAIKIA, BIPASHA - Indian Institute Of Technology; DAS, BIKASH KUMAR - Indian Institute Of Technology; Sharma, Brajendra; GOGOI, PARIKSHIT - Nowgong College

Submitted to: New Journal of Chemistry (RSC)
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2025
Publication Date: 11/6/2025
Citation: Deuri, D., Mahanta, J., Saikia, B., Das, B., Sharma, B.K., Gogoi, P. 2025. Hardwood-derived lignin as a tribo-positive filler in electrospun PVDF nanofibers for efficient triboelectric energy harvesting. New Journal of Chemistry (RSC) . https://doi.org/10.1039/D5NJ02897C.
DOI: https://doi.org/10.1039/D5NJ02897C

Interpretive Summary: The rising demand for sustainable power sources, driven by advancements in flexible electronics and lightweight devices has intensified research into newer energy-harvesting techniques. One of the techniques, nanogenerators, transforms mechanical energy into electrical energy, capturing energy from movements and vibrations. These nanogenerators are considered one of the most cost-effective green energy-harvesting techniques due to their high-power output, simple structure, small size, and cost-effectiveness. Typically, a nanogenerator consists of a substrate, electrodes, and friction layers possessing positive or negative charge. In recent years, the "back to nature" trend has driven the demand for utilizing renewable and eco-friendly biopolymers as advanced electrodes for these nanogenerators. In this study, abundant material lignin was isolated from the raw hardwood via the soda pulping method and utilized in developing polymer composite nanofibers with another polymer via an electrospinning technique. These lignin-based nanogenerators have exhibited impressive stability and endurance compared to the raw polymer. Utilization of more lignin will improve the economic viability of biofuel production and thereby help farmers by increasing the value of waste biomass generated on the farms.

Technical Abstract: It is essential to develop sustainable approaches to creating energy devices by using natural materials like lignocellulosic biomass. Lignin, which is most abundant in nature, serves as a tribo-positive filler due to chemical morphology. Here in, we isolated lignin from the raw hardwood via the soda pulping method and utilized the isolated lignin in developing composite nanofibers with polyvinylidene fluoride (PVDF), i.e., PVDF-Lignin Nanofiber (PLNF) via an electrospinning technique. Triboelectric characteristics of the different lignin concentration were evaluated against polytetrafluorethylene (PTFE). An enhancement in performance was observed compared to raw PVDF. The electrical output of triboelectric nanogenerators (TENG) made using PLNFs depends on their structural features, polarizability, dielectric properties, force, and frequency of vibration. Thus, P10-L5 TENG (PVDF 10 wt% with 5% lignin) generates highest output power density of approximately ~60 mWm-2. The high performance of P10-L5 TENG is attributed to uniform dimensions of nanofibers and high surface charge accumulation on the surface of PLNF. The lignin-based TENGs have exhibited impressive stability and endurance, enduring 10,000 cycles at 1 Hz, 3 Hz, and 5 Hz frequencies. The PLNFs produced a high-power output, while the ITO-PET sheets provided strength and flexibility, resulting in a stable, durable and sustainable TENG system.