Lotus leaves look dusty, yet their surfaces behave like a self-cleaning machine. Under a microscope, the skin of the leaf reveals a landscape of micron-sized bumps coated with nanoscale wax crystals. This rough, hydrophobic architecture creates what physicists call a superhydrophobic surface, where water barely touches the solid at all.Instead of spreading, droplets sit in a Cassie–Baxter state, p...More