Disintegration of Thin Liquid Metal Films Engendered by Aluminum Corrosion

Abstract

Liquid metals (LMs) illustrate a fantastic future. Thus, great endeavors are made to earn a comprehensive understanding of this fluid and carve it into a niche. Herein, by revisiting the combination of Ga-based LMs and aluminum (Al), a new phenomenon, namely the disintegration of LM films on encountering water, is identified. Deviating from previous investigations where the LM generally took the form of bulk puddles, the LM-Al slurry is spread as thin films here. In this case, Al debris embedded in the LM matrix hydrolyzes and therefore can exert disjoining pressure strong enough to split the thin film into countless tiny LM droplets. Based on this mechanism, transient circuits independent of substrate decomposition are realized. Furthermore, taking advantage of the portfolio strategy of pure LM and the LM-Al slurry, novel concepts of flood warning and information storage and encryption are demonstrated. Integrating these functions all in one demonstrates the versatility of the disintegration of thin LM films engendered by Al corrosion, which provides a scientific insight into ephemeral art and makes the Ga─Al combination more illuminating.