When a falling liquid droplet hits a surface, like a raindrop hitting pavement, it either flattens and spreads out evenly, or produces a sharp-edged splash. Now, a team of Chinese researchers has created a surface which allows the descending liquid to rebound and swirl around like a graceful dancer.
The team, led by Huizeng Li of the Chinese Academy of Sciences, Beijing (CAS), began by coating an aluminum surface with nonstick material, like the kind used on cooking utensils. The researchers then created several designs by covering portions of the nonadhesive area so that it would act like a normal, “wettable” surface – meaning it would cause the falling droplets to spread around. An ultraviolet (UV) light shone over the entire surface completed the setup.