Droplet Evaporation on Patterned Surfaces

Diffusion controlled evaporation of a sessile drop in an ambient gas is an important topic of interest because it plays a crucial role in many scientific applications such as controlling the deposition of particles on solid surfaces, in ink jet printing, spraying of pesticides, micro or nano material fabrication, thin film coatings, biochemical assays, drop wise cooling, deposition of DNA or RNA micro arrays, and manufacture of novel optical and electronic materials in the last decades. Thus, understanding the evaporation of such tiny or even nanoscale volumes of confined water is essential for many phenomena.

It has been found that a patterned structure usually brings about new properties (e.g., the super hydrophobicity resulting from a nanostructure , or the wetting state change of a droplet on a patterned surface), and these properties may lead to potential applications, e.g., self-assembly, self-cleaning, water harvesting, microfluidic pumping or efficient lubrication. So, the main objective of this project was to fabricate different patterned surfaces and study the alteration of the evaporation rate on these surfaces caused by the patterns.