Abstract:

Objective Wearable electronics has gained popularity in daily life, yet their energy supply remains a critical challenge. Triboelectric nanogenerator (TENG), which harvest low-frequency human motion energy through contact electrification and electrostatic induction, offer a promising solution as flexible electronic textiles. However, conventional TENG fabrics suffer from high internal resistance and low power output due to limited surface charge density and interfacial impedance mismatch, failing to meet practical device requirements. Addressing these limitations by reducing internal resistance and enhancing power generation efficiency is imperative to advance TENG textiles as viable, high-performance power sources for autonomous wearable systems.

Method In this paper, a miniature pair of needle-like devices is introduced to assist air breakdown in TENG fabrics for enhanced output power. Polyvinylidene fluoride-trifluoroethylene (P(VDF-TrFE)) nanofibers are electrospun as friction materials onto conductive fiber cloth electrodes using electrostatic spinning technology to prepare single-electrode flexible TENG fabrics operating in contact-separation mode. These components are precisely assembled using positioning platforms and 3D printing technology. The air-breaking device featuring a paired needle structure was systematically evaluated for both output performance and wearability when integrated with the triboelectric fabric system.

Results Through precise fabrication of tip discharge gaps (20-110 μm) using a micropositioning system, the resulting breakdown threshold voltages followed Paschen's law with measured values of 70 V (20 μm), 90 V (30 μm), 150 V (50 μm), 230 V (80 μm), and 350 V (110 μm). The integrated air-breakdown devices dramatically improved the triboelectric fabric's performance, elevating the open-circuit voltage by 170% (from 230 V to 390 V), doubling the short-circuit current (0.9 μA to 1.8 μA) and increasing transferred charge by 267% (30 nC to 110 nC), while scalability tests showed area-proportional enhancements with peak outputs reaching 532 V and 5.9 μA. The modified fabric exhibited excellent environmental stability across 40%-80% RH conditions, maintaining doubled current output compared to baseline devices, along with robust cyclic durability demonstrated by a stable 5.2 μA open-circuit current after 5 000 mechanical cycles and the ability to charge a 2 μF capacitor to 20 V within 60 s at 2 Hz operation (20% RH). Power optimization studies revealed a 33% boost in maximum load power (from 45 μW to 60 μW) coupled with a tenfold reduction in optimal load resistance (from 5×10⁸ Ω to 5×10⁷ Ω), enabling practical applications such as powering 33 serially connected LEDs and operating digital watches.

Conclusion This work develops lightweight, flexible TENG textiles with enhanced power output through strategic air breakdown engineering. By integrating micro-engineered needle pairs fabricated via precision positioning and additive manufacturing, submillimeter discharge gaps are created to concentrate electric fields, effectively lowering air ionization thresholds while maintaining compact device dimensions. This approach addresses intrinsic limitations of conventional TENG fabrics—notably high internal resistance and insufficient power density—through optimized charge transport pathways. The modified textiles demonstrate exceptional humidity resilience (40%-80% RH) and operational durability (5 000 cycles), successfully powering wearable electronics. These advancements establish a scalable framework for next-generation energy-autonomous textiles, addressing critical challenges in sustainable power supply for flexible IoT systems.

Key words: electrospinning, flexible E-textile, triboelectric nanogenerator technology, air breakdown device, output power, single-electrode