Study On Construction And Performance Of Long-acting Superhydrophobic Copper Surface

Copper and its alloy materials are widely applied in industry,agriculture,daily life and new industry because of their high thermal conductivity and excellent mechanical properties.However,copper is easily affected by the environment in its use.Especially in humid,high temperature and some corrosive media,the copper surface is easily corroded,consequently,the performance of its appearance,mechanical properties and will be reduced.So the application of copper can be limited greatly.The formation of superhydrophobic film on the copper surface can effectively reduce the corrosion rate of the copper surface.However,the superhydrophobic surfaces prepared by artificial technology have great limitations on the research and further development of super hydrophobic surfaces due to their poor stability and durability.Therefore,the preparation of superhydrophobic surface with durability has been paid much attention and studied by researchers both at home and abroad.In this thesis,a simple and environmentally friendly method was developed to prepare the surface of superhydrophobic copper by hydrothermal method.The wettability,surface microstructure,phase structure and chemical structure of the superhydrophobic copper surface were investigated by contact angle measurement,SEM observation,XRD measurement,FT-IR and EDS analysis.The wear resistance,corrosion resistance,stability and self-cleaning/anti adhesion properties of superhydrophobic copper surface were studied in detail.?1?Preparation of superhydrophobic copper surface:We explored the preparation of Cu based superhydrophobic surface by hydrothermal method.The effects of S/CTAB mmolar ratio,reaction temperature and reaction time on the wettability of copper surface were investigated.The copper based superhydrophobic surface was prepared under the conditions of S/CTAB mmolar ratio of 0.2 to 160 ^oC and 6 h,with a contact angle of 156.2 and 4 sliding angle.The results of XRD test,SEM image and FT-IR analysis show that the surface of the superhydrophobic copper is made up of a large number of Cu₂S crystal particles with micron and nanoscale two element rough structures,and the surface is grafted with hydrophobic alkyl long chains,the two groups endow the copper surface with superhydrophobicity.?2?Wear resistance and corrosion resistance of superhydrophobic copper surface:the wear resistance of copper based superhydrophobic surface was tested by friction test.The results show that the superhydrophobic surface treated by 200^oC still has good hydrophobicity after wearing distance of 500 mm.The corrosion resistance of copper based superhydrophobic surface was investigated by electrochemical work station and saline solution.The results show that the corrosion current density of superhydrophobic copper decreased by nearly 3 orders of magnitude compared with that of blank copper,and the corrosion inhibition rate of superhydrophobic copper surface was 99.9%.After immersion in NaCl solution,the contact angle of superhydrophobic surface decreases slowly,indicating that copper based superhydrophobic surface has excellent corrosion resistance.?3?The long effect of superhydrophobic copper surface:The droplets of different aqueous solution drop on the surface of superhydrophobic copper,and the droplets are spherical in shape,which shows that the prepared superhydrophobic copper has good hydrophobicity to different hydrophilic solutions.that is,the superhydrophobic surface has a certain universality.Secondly,the change of surface wettability of different pH droplets,UV irradiation time and one year after placing them is indicated.The results show that superhydrophobic copper surface has good stability of acid alkali resistance,UV resistance stability and storage stability.?4?Self-cleaning/anti adhesion properties of superhydrophobic surface:The effect of simulating the pollutants such as chalk ash,soot and soil on the surface of superhydrophobic copper under water droplet driving away from superhydrophobic copper surface is achieved and the adhesion of superhydrophobic copper to chalk ash and its surface after being immersed in it.Three different characterization methods are self-cleaning on the surface of the superhydrophobic copper.The anti adhesion properties were characterized.The results show that the water droplets are very easy to take away the contaminants on the surface of the superhydrophobic copper surface,and it is not contaminant in chalk ash dispersions.It shows that the surface of the superhydrophobic copper exhibits excellent self-cleaning/anti adhesion properties,which is due to the unique interaction between the micro and nano scale structure and the low surface energy of the super hydrophobic surface.