Many plants (and animals) structure there surfaces to be slippery to liquids. The Lotus leaf uses hydrophobic waxy bumps to ball-up water droplets which then roll-off taking with them dirt and parasites in a self-cleaning effect. The carnivorous Nepenthes Pitcher plant uses a layer of water held by a hydrophilic textured surface to create a surface on which the oily feet of insects slip, thus sliding them into its digestive trap. The first of these surfaces is slippery, but non-adhesive (droplets can be easily pulled off the surface), whereas the second is slippery and adhesive (droplets cannot be easily pulled off the surface). This relationship between slipperiness and adhesiveness is of great importance technologically.
Recently, we showed that the liquid friction for sliding along a solid surface can be understood using an analogy to Amontons’ laws for a solid sliding on another solid. In this experimental project, you will create surfaces with different levels of friction and adhesion to liquids and investigate the relationship to the wettability, friction and adhesion properties of the solid. Experimental work will include creating and characterizing a range of surfaces with different wettability and friction properties, taking and analyzing videos of droplets on surfaces using bespoke set-ups and a Krüss DSA system, and measuring droplet-surface adhesive forces using a tensiometer.
We expect that you will have a good degree in Engineering or Physics and a desire to perform practical experiment-based research. If successful, you will become a member of the Wetting, Interfacial Sciences and Engineering Group within the Institute for Multiscale Thermofluids at the School of Engineering. You will join a vibrant community of PhD students, postdoctoral research associates and academics working in various aspects of surfaces and wetting, and will develop as a scientist benefiting from our track record, which includes publications in top journals, international collaborations and contributions to key international conferences.
To Apply: https://www.eng.ed.ac.uk/studying/postgraduate/research/phd/water-repellency-adhesion-and-friction