By Irene Hsiao
A colloidal solution is a homogeneous dispersion of particles within a solvent. Colloids using polar solvents, such as water, achieve stability through electrostatic forces that push particles apart from each other, whereas colloids using nonpolar solvents have generally been unstable without using surfactants that prevent particles from aggregating. In “Stable Colloids in Molten Inorganic Salts” (Nature, 16 February 2017), Dmitri Talapin, Suri Vaikuntanathan, and collaborators show that nanoparticles of various metallic, semiconducting, rare-earth, and magnetic materials can be uniformly dispersed in molten inorganic salts. This work brings new fundamental insights to colloidal science and engineering.