化工学报 ›› 2011, Vol. 62 ›› Issue (5): 1352-1357.

• 表面与界面工程 • 上一篇    下一篇

Cassie状态到Wenzel状态转换的能量分析

隋涛,汪家道,陈大融   

  1. 清华大学精密仪器与机械学系,摩擦学国家重点实验室,北京 100084
  • 出版日期:2011-05-05 发布日期:2011-05-05

Energy analysis for transition from Cassie state to Wenzel state

SUI Tao, WANG Jiadao, CHEN Darong   

  • Online:2011-05-05 Published:2011-05-05

摘要:

从能量的角度分析了液滴在具有圆柱形阵列的硅片表面上从Cassie状态向Wenzel状态转换的条件。通过理论计算得到了液滴在不同参数的圆柱阵列上发生状态转换所需克服的能量势垒与液滴体积之间的关系曲线,并通过实验对体积大于2 μl的液滴做了验证。实验表明,对于体积大于2 μl的液滴可以通过增大液滴重力势能的方式实现从Cassie状态到Wenzel状态的转化,也可以保持液滴体积不变,通过增大圆柱阵列的柱间距的方法实现液滴从Cassie状态到Wenzel状态的转换。实验结果与理论分析保持一致。

关键词: 疏水性, 接触角, 状态, 状态

Abstract:

This study analyzed the Cassie state to Wenzel state transition of droplets on surfaces decorated with assemblies of cylindrical pillars arranged on a silicon wafer from the point of view of energy.The relation curve between energy barrier of state transition on the cylindrical array of different parameters and droplet size was calculated.For droplets size larger than 2 μltwo methods could be used for the transition from Cassie state to Wenzel state: increasing the droplets’ gravitational energy or maintaining constant droplets’ size and increasing the cylindrical array spacing distance.The experimental results were consistent with theoretical analysis.

Key words: 疏水性, 接触角, 状态, 状态