Advances in Liquid Metal Composites: Properties, Applications, and Future Prospects

•Post-transition LMs provide excellent opportunities for the construction of new composites with unprecedented properties. These LM-based composites take advantage of the low melting, fluidity, thermal, and conductive conductivity of LMs.•In general, two physical and chemical approaches are used for the fabrication of LM composites. While the former method mostly applies mechanical forces for mixing and downsizing LM particles, the latter method involves rapid chemical interactions between LMs and precursors.•Functionalized LM composites can be designed for desired applications through the modification of the surface or bulk of LMs with various materials, including metal particles, MXenes, ligands, graphene, 1D, and 2D materials.•Owing to their flexibility and conductivity, high reactivity, and biocompatibility, LM-based composites hold great potential to unlock numerous opportunities in soft electronics, sensing, and biotechnology.