Field's Metal Nanodroplets for Creating Phase-Change Materials

Liquid metal nanodroplets are an emerging class of nanostructures with profound potential in catalysis, sensing, and biomedical applications owing to their characteristically high surface area. However, the formation of metal nanodroplets is challenging because of their high surface tension; hence, high power sonification is typically applied, which adversely leads to polydispersed size distributions. Here, we demonstrate the surfactant-driven formation of sub-50-nm liquid metal droplets in a nonpolar solvent-oleic acid mixture, without the use of sonication. Oleic acid was found to be crucial for the droplet formation process and stabilization of the resulting colloid. It is proposed that micelle formation drives liquid metal droplet formation and stabilization. The synthesized metal nanodroplets may hold potential for applications as phase- and shape-change materials. By modifying the composition of the liquid metal nanodroplet's core with additional functional metals, this generic synthesis method can be extended to generate functional liquid metal nanodroplets with tailored properties.