Liquid Metal Micro- and Nanodroplets: Characteristics, Fabrication Techniques, and Applications

[Image: see text] Gallium-based liquid metal micro- and nanodroplets are being extensively explored in innumerable emerging technologies. Although many of these systems involve the interfaces of liquid metal with a continuous phase liquid (e.g., microfluidic channels and emulsions), the static or dynamic phenomena at the interface have been scarcely discussed. In this study, we begin by introducing the interfacial phenomena and characteristics observed at the interface between a liquid metal and continuous-phase liquids. Based on these results, we can employ various methods to fabricate liquid metal droplets with tunable surface properties. Finally, we discuss how these techniques can be directly applied to a wide range of state-of-the-art technologies including microfluidics, soft electronics, catalysts, and biomedicines.