Multifunctional liquid metal-infiltrated conductive wood enabled by cellulose nanocrystal-stabilized Pickering emulsion

A liquid metal–wood hybrid was constructed via Pickering emulsion engineering. • CNC-stabilized liquid metal droplets enabled uniform infiltration into wood. • In situ droplet coalescence generated a continuous conductive pathway. • Multiple functionalities were achieved in a single bio-based material platform. • The strategy offers a new route for sustainable structural electronic materials. Wood, as a renewable and mechanically robust bio-based material, holds great promise for advanced functional applications; however, its intrinsic electrical insulation severely restricts its applications in advanced electronic and energy systems. Here, we report a facile approach to fabricate multifunctional conductive wood by infiltrating liquid metal (LM) via cellulose nanocrystal (CNC)-stabilized LM Pickering emulsion (PE). A hierarchically porous cellulosic wood scaffold (CBW) with enlarged lumen structures, reduced cell wall thickness, and improved pore accessibility is constructed through the selective removal of hemicellulose and lignin, enabling efficient infiltration of LM nanoparticles. The CNC-stabilized LM PE droplets are employed as LM nanoparticles and are introduced into CBW via vacuum-assisted impregnation. Subsequent hot pressing is proposed to facilitate the formation of an interconnected conductive network through the pressure-induced coalescence of discrete LM droplets. The resulting conductive wood (DCBW@LM) exhibits a high electrical conductivity of 310.2 S m −1 , good Joule heating performance, efficient near-infrared photothermal conversion, and stable EMI shielding effectiveness of 25–30 dB in the X-band. Moreover, DCBW@LM demonstrates significantly enhanced mechanical strength and flame resistance properties. This work establishes a facile strategy to construct highly conductive, photothermal, EMI shielding, robust, and improved short-term flame resistance wood and integrate LM with porous materials for sustainable, high value-added, and multifunctional applications. Download: Download high-res image (167KB) Download: Download full-size image