Upcycling Disposable Mask Straps Into Asymmetric PEDOT:PSS-Based Triboelectric Nanogenerators Enabled by Saline-Induced Power Enhancement.

This work demonstrates a sustainable upcycling strategy that transforms discarded mask straps into flexible direct-current triboelectric nanogenerators (DC-TENGs) through an eco-friendly NaCl-assisted modification. The PEDOT:PSS/PVA/Pullulan composite simultaneously serves as the electrode and triboelectric layer, enabling a simplified and metal-reduced fabrication. The saline treatment introduces Na+-PSS- coordination, which sustainably enhances molecular mobility, interfacial polarization, and charge transfer without the need for toxic dopants or complex post-processing. The resulting device delivers a peak voltage of ∼1 V, a current of ∼180 µA, and a maximum power density of 0.5 W m- 2 under mechanical deformation. By utilizing water-based NaCl as a benign ionic modifier, this approach exemplifies a circular and green pathway to improve energy harvesting performance while mitigating mask waste pollution. The developed NaCl-enabled DC-TENG offers a practical route toward sustainable, self-powered wearable and communication systems aligned with global carbon-neutral and SDG objectives.