Fractal Surfaces of Molecular Crystals Mimicking Lotus Leaf with Phototunable Double Roughness Structures
mediaposted on 25.07.2016, 00:00 by Ryo Nishimura, Kengo Hyodo, Haruna Sawaguchi, Yoshiaki Yamamoto, Yoshimune Nonomura, Hiroyuki Mayama, Satoshi Yokojima, Shinichiro Nakamura, Kingo Uchida
Double roughness structure, the origin of the lotus effect of natural lotus leaf, was successfully reproduced on a diarylethene microcrystalline surface. Static superwater-repellency and dynamic water-drop-bouncing were observed on the surface, in the manner of natural lotus leaves. Double roughness structure was essential for water-drop-bouncing. This ability was not observed on a single roughness microcrystalline surface showing the lotus effect of the same diarylethene derivative. The double roughness structure was reversibly controlled by alternating irradiation with UV and visible light.