Solar steam nanobubbles.

Silica-gold core-shell nanoparticles that are immersed in water act as efficient nanoscale generators of steam when illuminated with sunlight. In their paper in this issue of ACS Nano, Halas, Nordlander, and co-workers demonstrate this intriguing phenomenon that results from the nucleation of steam at the surface of individual nanoparticles that are heated by the sun. The same effect is also used to demonstrate distillation of ethanol. The solar steam nanobubble generation phenomenon results from the complex interplay of many different phenomena that occur at the nanoscale, and can find a broad range of applications.