Application of superhydrophobic edge effects in solving the liquid outflow phenomena

In this paper, we discuss various edge effects on the outflow behaviors of water around the edge to solve the troublesome problem that frequently brings about great inconvenience in daily lives. A simple method of pressing a drop over the edges of a conical frustum was adopted here to explore the stability of a suspended drop around the edges. On the basis of experiments and theoretical analyses, the critical pressure P(c) and the pressing work DeltaE(w) were used for characterizing the stability of water around an edge, which were found to be closely related to the geometric morphologies, the microstructures of sides, and the material characteristics. The stability of suspended drops around the edge may be enhanced by increasing the rise angle omega, the actual rise angle phi, and the size of edge circles and by using low surface energy materials. Thus, a facile and effective strategy has been successfully developed. We believe that these findings will help to design novel tubes and bottles without a liquid outflow problem.