Porous Plant Leaf Inspired Superhydrophobic Surface And Its Performance Study

As its wide applications in the fields of self-cleaning, anti-corrosion, anti-icing, enhanced heat transfer, the preparation of superhydrophobic surface has attracted many researchers. Specially, nature has inspired us a lot. However, the existing methods such as photolithography, chemical-etching, template method and Self-assembly have many disadvantages, for examples, not suitable for large-scale preparation, environmental pollution, surface topography incontrollable and so on. The work was inspired by citrus and bamboo leaf structure in nature, combining breath figure method and nano-particles modification, successfully fabricated a novel coating on copper. It can be used for large-scale fabrication and is eco-friendly. Moreover, the preparation method is simple and has a well regulation of the micro/nano structure. The research contents are as follows:1. Linear polystyrene was used as raw material, ordered honeycomb film was fabricated on copper using breath figure method.2. Through controlling relative humidity and speed of moist air, the mean hole diameter can be regulated. Under certain relative humidity, control air speed from 0.1 m3/h,0.15 m3/h to 0.2 m3/h, corresponding hole diameter were 2.67?m,4.64?m,8.94?m.3. Based on Step1, Step2, dip-coating method was used to modify a spot of nano-SiO2 on the surface of outer holes. A micro/nano structure was obtained then. It has contact angle of ?156°with low sliding angle(less than 4°). Focusing on surface characterization, surface morphology, chemical composition, surface wettability were studied by SEM, FITR, contact angle test technology and roughmeter. Furthermore, the influence of different nanoparticles, concentration of nanoparticles, different liquid medium on the surface wettability were systematic studied.4. Focusing on the dynamic wettability of the surface, high speed camera was used to study its self-cleaning property and droplet impact property. The surface exhibit ultra repellence to deionized water, milk, orange juice and water droplet can easily take off dust on the surface. It shows excellent self-cleaning property. The droplet impacting experiment indicates the surface has well superhydrophobicity under dynamic environment. Compared with similar literatures, water droplet has shorter contact time on the surface(less than 10 ms) and can bounce off it quickly. It will provide scientific guidance in the fields of anti-icing, anti-frosting for superhydrophobic surface.