Abstract
Phragmites communis leaf (PCL) is anisotropic, superhydrophobic and shows a self-cleaning effect. The water contact angle (WCA) values along the vertical and parallel vein directions on PCL are 153° ± 2° and 148° ± 2°, respectively. In contrast, the water sliding angle (WSA) values along the vertical and parallel vein directions for PCL are 12° ± 2° and 7° ± 2°, respectively. The epidermal wax makes the leaves intrinsically hydrophobic. The microstructure of the PCL surface shows sub-millimetre-, micron- and nanometre-scale structures. The sub-millimetre ridge structure is the main reason for the anisotropy of the leaves. The micron-scale papillae structure has a strong hydrophobic enhancement effect, and the nanoscale sheet structure is the key factor in achieving a stable Cassie state, as well as superhydrophobicity and self-cleaning activities. PCL-like polydimethylsiloxane (PDMS) samples fabricated by template transfer technology exhibited the sub-millimetre ridge structure and micron-scale papillae from the natural PCL; they also show obvious anisotropy and strong hydrophobicity and have a certain self-cleaning effect. The WCA and WSA values along the vertical and parallel vein directions on PCL are 146° ± 2°, 23° ± 2°, 142° ± 2° and 19° ± 2°, respectively. The preparation of a biomimetic PCL surface has broad application prospects in micro-fluidic control and the non-destructive transmission of liquids.
Highlights
When the water contact angle (WCA) value exceeds 150◦ on a surface, the surface is generally considered to be superhydrophobic [1,2,3]
The micron-scale papillae structure has a strong hydrophobic enhancement effect, and the nanoscale sheet structure is the key factor in achieving a stable Cassie state, as well as superhydrophobicity and self-cleaning activities
Microscopic observations show that the middle vein of the Phragmites communis leaf (PCL) is almost parallel to the lateral veins (Figure 2b), so the vein sequence of PCLs is parallel, which
Summary
When the water contact angle (WCA) value exceeds 150◦ on a surface, the surface is generally considered to be superhydrophobic [1,2,3]. Superhydrophobicity is an interesting phenomenon, but more importantly, it has inspired our thinking regarding wettability. More and more possible applications, such as self-cleaning, anti-fogging, and anti-corrosion properties, printing, sensors and water-oil separation, are being proposed and attempted [4,5,6,7,8]. The wide application prospect will inevitably prompt more research and exploration on the mechanism and preparation of superhydrophobicity. Learning from nature is an important method of innovation.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
