Hemicellulose-Based Water-Soluble Triboelectric Nanogenerator for Advanced Flexible Electronics.

Abstract

Biodegradable hemicellulose has been recognized as a promising triboelectric positive material due to its polyhydroxy structure. However, its inherently low triboelectric polarity severely limits its application in flexible wearable sensor systems. Herein, a hemicellulose-based composite film with excellent triboelectric properties was designed. Acrylamide (AM) monomers were grafted onto the hemicellulose backbone through a free radical graft copolymerization reaction. The amino group's strong electron-donating capability enhanced molecular polarization. Synergistic dynamic hydrogen/covalent bonding networks improved mechanical properties (strength, fatigue/thermal expansion resistance) through optimized cohesive energy, thereby boosting charge transfer and significantly enhancing macroscopic triboelectric performance. The HC/PAM₄-based TENG delivers 81 V open-circuit voltage, 6.6 µA short-circuit current, 10 nC transferred charge, and 49 mW/m² peak power density at 1 Hz. Self-powered, the device monitored human motion by analyzing distinct signal waveforms for precise recognition. The HC/PAM4 film retains recyclability through water dissolution-drying cycles via dynamic hydrogen bonds, maintaining stable properties over 5 cycles: water solubility time (140 ± 2 s), tensile strength (10 ± 2 MPa), and elongation at break variation (<5%) under ambient conditions, demonstrating excellent long-term stability. Our finding offers an effective strategy for enhancing hemicellulose-based triboelectric materials, enabling wearable self-powered sensors toward eco-friendly intelligent devices.