Researchers at the Department of Energy’s Lawrence Berkeley National Laboratory have figured out a way to 3D print structures made entirely of liquids. According to the researchers, this advance is the first step toward creating liquid electronics that can conform to any shape and be implemented in stretchable devices.
As detailed in Advanced Materials, the 3D printed tubes of water were up to a millimeter in diameter and could be printed in spiraling shapes that were several meters long. To create these threads, the researchers used an off-the-shelf 3D printer that they modified by adding a syringe that would inject water into a small box of silicone oil.
This wasn’t just your run of the mill tap water, however. The Berkeley lab researchers seeded the water with gold nanoparticles and dispersed polymer ligands (a ligand is a group of atoms that binds to a metal atom) in the oil. Thus, when the gold-laced water and polymer ligand-laced oil were combined, the ligands are attracted to and bind with the gold nanoparticles.
This, in effect, creates a nanoparticle sheathe around the water that prevents it from breaking up into droplets and maintains the shape of the water tube. The researchers refer to this combination as a nanoparticle supersoap.