Directional Continuous Bouncing Behavior of Water Droplets on a Surface with a Chemical Gradient

• DOI: 10.1021/acs.langmuir.4c03379
• Publication Date: 2025-02-25T17:47:28Z
• Authors: Yue Zhang; Ao Gong; Tao Wang; Shuai Zhang; Ying Nie; Xun Sun
• Keywords: Temperature Gradient

Manipulation of directional bouncing behavior liquid droplets after impacting solid surfaces is highly significant for biological, agricultural, engineering, and industrial applications. Here, we prepared a surface with chemical gradient on Ti-6Al-4V substrate, which multiple long-range movement has been achieved. The wetting the vapor-deposited reached 2.5° mm-1 by finely controlling distribution low energy functional groups. Droplet adhesion force analysis was carried out to visualize variation wettability. On this inhomogeneous wettability, droplet repeated rebounding 8 times along direction gradient, displaying an interesting phenomenon "droplet trampoline". maximal rebound height horizontal jumping distance 8.36 10.19 mm, respectively. Additionally, underlying mechanism behind consecutive thoroughly elucidated from perspectives. This research anticipated advance understanding continuous bounce provide promising strategy delicately manipulate droplets.