Active Corrosion Triggered Liquid Metal Dewetting

Abstract Liquid metals (LMs), as an emerging group of functional materials, possess the necessary conditions for dewetting. However, LM dewetting garnered grossly inadequate attention. Here, an intriguing phenomenon termed active corrosion‐triggered dewetting (ACT‐Dewetting) of LMs is reported. Distinct from traditional dewetting which mainly depends on physical treatments (e.g., laser irradiation, evaporation) for initiation, the ACT‐Dewetting couples mechanics, chemistry, and physics, which enables gallium (Ga)‐based and Ga‐free (e.g., fusible alloy) LMs spread on sacrificial metals (e.g., Al, Mg) readily dewet into numerous microdroplets in seconds along with substrate corrosion and gas emission. This gives birth to a novel method for fabricating LM microdroplets. Besides, due to the consistent metallic luster of painted LMs on various substrates and selective corrosion of substrates, ACT‐Dewetting is demonstrated as an effective information encryption method. With these proof‐of‐concept illustrations, it is anticipated this ACT‐Dewetting strategy would facilitate more innovative studies of LMs.