Water-repellent surfaces that last
In the first part of this video, the effects of condensation on three different surfaces are compared: On the left, a bare silicon surface, showing how water droplets remain "pinned" in place as they get bigger and bigger; in the center and right panels, two different rare-earth oxide ceramic surfaces, cerium oxide and erbium oxide, show how the droplets do not stick and instead are rapidly shed from the surface, increasing the efficiency of the condensation process.
In the second part, a rare-earth oxide surface that has been patterned to increase its water-repelling qualities, as shown on the left, causes a water droplet to simply bounce away, rather than sticking to the surface and spreading out.
Video: Gisele Azimi, Rajeev Dhiman, Hyuk-Min Kwon and Adam Paxon
Read more: http://web.mit.edu/newsoffice/2013/ceramic-hydrophobic-materials-0120.html