Functionalized wood with tunable mechanically toughness, transparent and conductivity for multi-functional self-powered sensor

Abstract

Natural wood with the merits of hierarchical structure and renewable has gained increasing attentions in sustainable electrical device. However, the development of functionalized wood integrating excellent mechanical robustness and conductivity for electronics remains ongoing challenge. Herein, a novel strategy of polymerizable deep eutectic solvents (PDES) treated modified-wood was developed for the preparation of multi-functionalized wood for high-performance self-powered sensors. In this strategy, the methacrylic anhydride-modified wood simultaneously containing methyl groups and acrylate groups was first prepared, and then employed to react with PDES to construct the covalent-noncovalent dual crosslinked functionalized wood (FW). The in-situ polymerization of PDES with modified-wood not only achieved the excellent mechanical toughness (2.37 MJ/m3), optical transmittance (86 %) and conductivity (34.48 mS/m) but also endowed the FW with outstanding antibacterial performance. Given these features, the FW was applied as electrode materials for assembling flexible and high-performance wood-based TENG (FW-TENG). More impressively, the introduction of the electron-donating group (-CH3) improved the polarity of the FW, which significantly increased the transferred charge density of FW-TENG about 2.91 times. And the FW-TENG showed the promising applications in human motions monitoring and information encrypting. This work paved a new strategy for developing the multi-functionalized wood-based materials for self-powered electronics.