Versatile liquid metal composites constructed using an organic–inorganic hybridization strategy for flexible electronics

Abstract

Liquid metals (LMs) with high electrical conductivity and fluidity are regarded as promising materials for developing multifunctional materials. However, the poor interfacial wettability caused by high surface tension of a LM and filler agglomeration impedes its applications in flexible electronics. Herein, a facile and cost-effective approach for fabricating LM composites is demonstrated through an organic–inorganic hybridization strategy combined with solvent-assisted dispersion (SAD) technology. Integration of inorganic fillers (e.g., CaCO₃) and organic materials (i.e., starch and polyvinyl alcohol (PVA)) into LMs enables a 3D solid–liquid bi-continuous conductive network with abundant hydrogen bonds. Notably, LM composites exhibit excellent electrical conductivity (10⁶ S m⁻¹) and can be processed to form LM chalk, film and conductive coating. Leveraging the excellent malleability, LM-based circuits obtained via a direct-writing method can be used to design electrical-heaters and smart capacitance sensors. In addition, bulk LM layered composites with a biomimetic nacre-like structure exhibit enhanced impact resistance and a flexural modulus of 45 MPa. Furthermore, LM composites can be integrated into an actuator with fast response time and a wireless communication device. This organic–inorganic hybridization strategy breaks the traditional compatibility paradox between high conductivity and uniform dispersion. It not only extends the fundamental knowledge of LM composites, but also paves a sustainable way for constructing multifunctional LM-based electronics, applicable in soft robotics, wearable electronics and smart sensors.