Janus Asymmetric-Wettability Cellulosic Triboelectric Materials Enabled by Noncovalent Interactions

High-strength cellulose materials, endowed with both biocompatibility and lightweight characteristics, are accelerating the advancement of artificial intelligence technologies in wearable electronics. However, the abundance of hydroxyl groups on cellulose surfaces imparts pronounced hydrophilicity, severely constraining the cellulose's wet strength. This study proposes a noncovalent bonding strategy based on hydrogen bonding and electrostatic interactions and develops a Janus-type cellulose triboelectric material with an asymmetric wettability. Benefiting from its low surface wettability and moisture-barrier properties, the material effectively suppresses water-induced damage to the cellulose network. Compared with conventional cellulose materials, the Janus asymmetric-wettability triboelectric material exhibits a 917% enhancement in wet strength. Furthermore, the triboelectric material was integrated into a triboelectric nanogenerator (TENG) and sensors, demonstrating efficient energy harvesting and stress-sensing capabilities. This work offers a perspective for addressing the long-standing challenge of insufficient wet strength in cellulose materials and provides a promising reference for constructing environmentally stable energy harvesting and conversion devices.