In situ observations for growth kinetics of water droplets on Bambusa multiplex leaves

Abstract

The wetting of material surfaces is an important topic and is now being intensively investigated toward various practical applications, yet most previous studies have adopted postmortem methods. Fortunately, the recent development of environmental scanning electron microscopy (ESEM) means that hydrated samples can be observed in their native state, as well as dynamic surface reactions. Here, we use in situ ESEM observation to explore the microscopic growth dynamics of water droplets on adaxial and abaxial surfaces of Bambusa multiplex leaf (BML) during wetting. Our results show that, due to the dramatic structural differences between adaxial and abaxial surfaces, the growth of water droplets on the two sides is quite different. Furthermore, the growth kinetics of water droplets on different BML surfaces are quantitatively discussed. This conceptual study demonstrates a straightforward pathway to understanding the wetting behavior, and the results may pave the way for further research on bio-inspired materials.