Fig. 1: Different vapor dynamics of drops on hot surfaces.

a, b Drop on a hot superhydrophobic surface. Benefitting from the beneath “intact” vapor film, a water drop almost “frictionless” wanders on the surface. c Schematic of a water drop sitting on a hot chemically heterogeneous surface. d Synchronized high-speed image sequences showing the drop spins on the chemically heterogeneous surface. The drop elongates and spins with a period of 74 ms. The red arrows indicate the rotation direction of the drop. e Width of the drop projection W and position of the drop centroid X as functions of time t. X remains almost unchanged, while W varies periodically with time t. The period is 37 ms, which is half of the drop rotation period. The data are collected from the rotating process of (d). f Phase diagram summarizing the drop volume and the substrate temperature T required for the drop spin. The temperature of the substrates in (b, d) is 120 °C, and the volume of the drops is 60 μl.