PLUS-M: a Porous Liquid-metal enabled Ubiquitous Soft Material

Abstract

Liquid metal transforms into a porous structure and floats on the water surface with heating.

Abstract

A Porous Liquid-metal enabled Ubiquitous Soft Material (PLUS-M) was fabricated through loading chemically reactive iron nanoparticles into eutectic gallium–indium alloys (EGaIn), whose porosity and shape could be easily regulated via remote control. Such a PLUS-M could expand to a surprisingly large magnitude in a short time, say seven times its original volume, and generate adjustable closed cell foams inside. Owing to this unique property, the density of the PLUS-M can be easily controlled, allowing the PLUS-M to float on water or even pull up underwater heavy objects above the surface when subjected to heating. What's more, this porous material can transform between liquid and solid states through controlling the oxidation level of gallium using methods like heating and stirring. The reversible transformation between the solid porous structure and liquid state could be achieved more than 100 times without obvious performance degradation.