Recent progress in experiments for sessile droplet wetting on structured surfaces

Abstract Wetting of a sessile droplet on structured or patterned surface can be found in a broad range of applications. The researchers have been promoted to keep working on the topic. The review is based on the recent experimental advances on the sessile droplet wetting on the hydrophobic, hydrophilic, or their combined surfaces under the isothermal conditions, and on the heating or cooling substrates having nonisothermal conditions. More attention has been paid on the wetting configuration between the sessile droplet and the structured substrate, the research gap has been discussed on identifying the three-phase line shape. The further three-dimensional measurement for the sessile droplets on the patterned surfaces with focusing more on the contact line of sessile droplets might reveal new physical insight. This review targets at building a holistic overview on the sessile droplet wetting behaviors on the structured substrate in the past two years.