Department of Metallurgy and Ceramic Science Graduate School of Science and Engineering, Tokyo Institute of Technology 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Langmuir. 2010 Aug 17;26(16):13305-9. doi: 10.1021/la101663a.
Dew condensation effects on the wettability of rough and smooth coatings of two fluoroalkylsilanes (FAS3 and FAS17) were investigated by controlling the temperature. Contact angles of the coatings decreased concomitantly with decreasing surface temperature. Inflection points in the temperature dependence of contact angles were observed at the dew point. They were attributable to the change of the interfacial free energy of the solid-gas interface by water adsorption. The contact angle decrease suggested a mode transition from Cassie to Wenzel on the rough surface, and resulted from the surface wettability change and the increase of the condensation amount of water. The contact angle change by increasing temperature from -6 degrees C revealed that the Wenzel mode is more stable than Cassie's mode.
通过控制温度，研究了露水凝结对两种氟烷基硅烷（FAS3 和 FAS17）粗糙和平滑涂层润湿性的影响。涂层的接触角随表面温度的降低而同步下降。在露点处观察到接触角对温度的依赖性的转折点。这归因于水吸附引起的固-气界面界面自由能的变化。接触角的下降表明粗糙表面上从 Cassie 到 Wenzel 的模式转变，并且是由于表面润湿性的变化和水的凝结量的增加所致。从-6°C 升高温度导致接触角的变化表明，Wenzel 模式比 Cassie 模式更稳定。
