Flexible Triboelectric Nanogenerators Fabricated by PAN-supported Self-aggregation Crosslinked PVA Composite Films for Kinetic Energy Harvesting and Pervaporization Applications

Abstract

In this study, a high-performance and swell-resistant triboelectric nanogenerator (TENG) has been proposed, specifically designed for high-humidity environments to meet the challenges of swelling problem and performance degradation. The composite film was fabricated by combining self-aggregation crosslinking reactions for polyvinyl alcohol (PVA) through ammonium persulfate (APS) initiations and interface physicochemical structure regulations for polyacrylonitrile (PAN) support layer. The treatment of PAN films with sodium hydroxide (NaOH) and tannic acid (TA) significantly enhances their electron affinity and electrical properties. Furthermore, the film exhibits superior swelling resistance, mechanical strength, and triboelectric characteristics. Owing to higher positive surface potential and optimized interface modulation, the constructed TENG using 8 wt% PVA initiated by 1.25 wt% APS spined on modified PAN support layer (PA_8-1.25NTP-TENG) presents excellent stability and performance, with the I_SC density reaching 180.9 mA·m^-2, voltage of 1396 V, and power density of 89.66 W·m^-2. Practically, the TENG successfully powered electronic devices and generated signals through human movements, harvesting biomechanical energy. Additionally, a self-powered ethanol pervaporation dehydration detector was developed, showcasing excellent permeability selectivity and stable performance in high humidity and elevated ethanol concentrations. Notably, in the dehydration process, the concentration of ethanol after membrane treatment achieves exceeding 99.99%. This work introduces a novel strategy for enhancing the electrical properties of TENGs, providing valuable insights into material interface regulation mechanisms during energy conversion.