Liquid Metal Hydrothermal Rheological Modification Method for High Performance Gallium‐Coated Carbon Microparticle Composites

Abstract Gallium‐based liquid metal (LM) is widely used in flexible electronics, optics, and green synthesis due to its excellent conductivity, flexibility, and self‐healing capabilities. However, LM's inherent fluidity and high surface tension greatly limit their practical applications. Therefore, there is a strong demand for developing LM composites that are easy to control and exhibit outstanding performance when used flexibly. In this work, the LM hydrothermal rheological modification method is proposed to synthesize Ga‐coated carbon microparticles, and the highly miscible rheological modification of LM is realized by mixing LM and Ga‐coated carbon microparticles. Including carbon microparticles in the LM improves the mechanical strength of the composite, thereby overcoming the limitation of the LM that has a low mechanical strength. By controlling the volume fraction of carbon microparticles in LM, electrical conductivity is increased by 30% and thermal conductivity by more than 2.0 times that of pure LM. In addition, the fundamental interfacial wetting behavior is demonstrated at the interface of LM and Ga 2 O 3, and the rheological modification mechanism of LM is explained by carbon particles. This work presents a novel method for preparing high‐performance polymer materials and discusses their broad potential applications in thermal interface materials, wireless energy transfer, and flexible electronics.