High-Performance V 2 O 5 /Chitosan Composite Film-Based Triboelectric Nanogenerator for Mechanical Energy Harvesting and Smart Safety Wearable Applications

The growing demand for sustainable energy sources and the rapid growth of wearable electronics have driven the need for efficient, flexible, and self-powered energy-harvesting systems. In this report, we demonstrated the fabrication of flexible, low-cost, portable, and self-powered triboelectric nanogenerators (TENGs) using vanadium pentoxide (V 2 O 5 (VO)) nanoparticle (NPs)-loaded chitosan (CS) composite films to be used for energy harvesting, storage, and biomechanical and sensing applications. The VO phase’s purity and surface morphology were confirmed by X-ray diffraction (XRD) and field-emission scanning electron microscope (FE-SEM) analysis. The VO/CS composite thin films were prepared by systematically varying the VO weight concentration (0, 0.5, 1, 2, and 3 wt %) within the CS matrix. The TENG device was fabricated using different wt % VO/CS composite films and ecoflex as tribo positive and tribo negative layers, respectively, and aluminum was used as a conductive electrode to both the tribo films. A contact-separation mode was used to evaluate the electrical output of the TENG device. The optimized 2 wt % VO/CS composite film-based TENG generated the maximum electrical output voltage, current, charge density, and power density of ∼205 V, 6.2 μA, 96.5 μC/m 2, and 3.9 W/m 2, respectively. The fabricated TENG device demonstrated robust performance and sustained stable electrical output over a long period. In addition, the generated electrical energy was efficiently stored in capacitors and utilized to power up low-power electronic devices. Furthermore, an optimized TENG device was placed at various locations on the human body to evaluate electrical output from biomechanical energy. Thereafter, the TENG-powered self-illuminating device was demonstrated as a smart safety walker wearable bracelet alert system.