Flexible Triboelectric Nanogenerator Based on PAN/PTFE Nanofibers and BaTiO3/PDMS Composite Films for Wearable Applications

Abstract The rapid development of flexible electronics and wearable technologies has created an urgent need for triboelectric nanogenerators (TENGs) that combine high electrical output, mechanical robustness, and conformal flexibility. However, achieving this combination through rational materials design remains challenging. Herein, a flexible TENG is developed through composite tribolayer engineering, using a PAN/PTFE composite nanofiber membrane as the positive tribolayer and a BaTiO3/PDMS composite film as the negative tribolayer. Electrospinning and solution casting were integrated to regulate the tribolayer microstructure and functional response. The PAN/PTFE nanofibrous membrane containing 0.5 wt % PTFE exhibited the highest tensile strength of approximately 1.36 MPa, whereas the 12 wt % PAN/1.0 wt % PTFE composition was selected for optimal electrical output. The 2 wt % BaTiO3/PDMS composite film provided the highest triboelectric output among the investigated BaTiO3 loadings. SEM, XRD, XPS, and SEM–EDS analyses provided complementary information regarding composite morphology, crystalline characteristics, and filler incorporation. Under optimized conditions, the TENG delivered an open-circuit voltage of approximately ±60 V and a short-circuit current of approximately ±0.5 μA in the periodic contact–separation mode under a contact force of 5 N at 1 Hz, with stable responses over different driving frequencies. The highest peak output power and power density within the investigated load-resistance range reached 27.59 μW and 11.04 mW m–2, respectively. Numerical simulations and additional separation-distance measurements showed qualitatively consistent trends in the electrostatic response of the device. Moreover, repeated foot-stepping experiments produced reproducible voltage signals, demonstrating the feasibility of biomechanical energy harvesting under wearable-like conditions. This work provides insights into the relationships among composite composition, microstructure, mechanical properties, and electrical output, supporting the further development of flexible TENGs for wearable energy-harvesting applications.