A heatshield for 'never-wet' surfaces: Engineers repel even near-boiling water with low-cost, scalable coating

Superhydrophobic surfaces—those famously “never-wet” materials that make water bead up and roll away—have a stubborn weakness: hot water. Once temperatures climb above roughly 40 degrees Celsius, many superhydrophobic coatings abruptly lose their magic. Instead of skittering off, hot droplets start sticking, soaking into the surface texture and leaving behind wet patches and residue.