Patterning Superhydrophobic Surfaces To Realize Anisotropic Wettability and To Transport Micro-Liter-Sized Droplets to Any Type of Surface

In this work, we describe simple methods for fabricating superhydrophobic films from carbon nanotube (CNT)/polybenzoxazine coatings. We observed anisotropic wetting and controlled mobility of microliter-sized droplets on as-prepared superhydrophobic surfaces that exhibited patterned wettability after being scraped with a blade. The as-prepared patterned superhydrophobic surfaces possessed both static anisotropic wettabilities (different static contact angles in parallel and perpendicular directions) and dynamic anisotropic wettabilities (different sliding angles in different directions). Most interestingly, water droplets suspended from the patterned superhydrophobic surface also displayed anisotropic mobility. Furthermore, such patterned superhydrophobic surfaces can be used to transport microliter-sized droplets to any type of surface, regardless of its surface wettability. The commercial availability of the raw materials and the simple fabrication and operation process should make such surfaces attractive in academic research and industrial applications.