Rings and Hexagons Made of Nanocrystals:  A Marangoni Effect

Abstract

By controlling solvent evaporation rates, it has been possible to form micrometer rings and hexagonal arrays made of nanocrystals of different sizes, shapes and materials. Such patterns are driven by surface tension gradients that induce Bénard−Marangoni instabilities in the liquid films. The resulting self-assembled structures are consistent with theoretical prediction of hydrodynamic instabilities.