title: Microscopic receding contact line dynamics on pillar and irregular superhydrophobic surfaces.
abstract: Receding angles have been shown to have great significance when designing a superhydrophobic surface for applications involving self-cleaning. Although apparent receding angles under dynamic conditions have been well studied, the microscopic receding contact line dynamics are not well understood. Therefore, experiments were performed to measure these dynamics on textured square pillar and irregular superhydrophobic surfaces at micron length scales and at micro-second temporal scales. Results revealed a consistent "slide-snap" motion of the microscopic receding line as compared to the "stick-slip" dynamics reported in previous studies. Interface angles between 40-60° were measured for the pre-snap receding lines on all pillar surfaces. Similar "slide-snap" dynamics were also observed on an irregular nanocomposite surface. However, the sharper features of the surface asperities resulted in a higher pre-snap receding line interface angle (~90°).
authors: Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904, USA.
authors: Yong Han
authors: YH
authors: Yeong
authors: Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904, USA.
authors: Athanasios
authors: A
authors: Milionis
authors: Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904, USA.
authors: Eric
authors: E
authors: Loth
authors: Smart Materials, Central Laboratories, Istituto Italiano di Tecnologia, Genoa, 16162, Italy.
authors: Ilker S
authors: IS
authors: Bayer