Preparation And Properties Of Superhydrophobic Surface On Phosphor-Copper

In this thesis we have fabricated superhydrophobic surfaces on phosphor-copper meshes（foils） with a simple wet chemical method. By renewing the synthetic method, we hope to establish a low-cost and simple route to fabricating the so-called superhydrophobic surfaces. By applying various advanced characterization techniques to analyze the correlation among the chemical composition-micro/nanohierarchical structure and performance of the superhydrophobic surfaces, we hope to provide important support to their large-scale commercial application in both theory and practice. The main contents and results are as follows:（1） A simple aqueous solution-immersion process was established to fabricate highly dense ordered Cu₂ O nanorods on commercial phosphor-copper mesh, with which the preparation was accomplished in distilled water. The present method, with the advantages of simple operation, low cost, short reaction time and environmental friendliness, can be well adopted to fabricate desired Cu₂ O nanostructures on the phosphor-copper mesh under mild conditions. After surface modification with 1-dodecanethiol, the Cu₂ O nanostructure obtained on the phosphor-copper mesh exhibits excellent superhydrophobicity and superoleophilicity. Besides, a “mini boat” made from the as-prepared superhydrophobic phosphor-copper mesh can float freely on water surface and in situ collect oil from water surface. This demonstrates that the present approach, being facile, inexpensive and environmentally friendly, could find promising application in oil-water separation and off shore oil spill cleanup.（2） With a view to the time-consuming procedure and/or high cost for the fabrication of superhydrophobic materials, a simple one-step process was developed to render phosphor-copper meshsurfaces with superhydrophobicity. Thus coralloid Cu₂ O nanostructure was generated on phosphor-copper mesh surface by immersing the mesh in the mixed solution（volume ratio 3:1） of distilled water and the ethanol solution of 1-dodecanethiol(1×10^-2 mol?dm^-3) containing at room temperature. The as-prepared phosphor-copper mesh exhibits very high advancing/receding contact angles of（161.2 ± 0.7）° and（160.2 ±0.3）°, as well as a low contact angle hysteresis of（1.1 ±0.5）°. Moreover, four types of oils and organic solvents（gasoline, diesel oil, n-hexane, toluene, and chloroform） can be well separated by the mesh at an efficiency of more than 98%. Compared with the traditional two-step preparation process, the present method has advantages of easy operation, reduced material consumption, short reaction time and high efficiency. This demonstrates that the present approach, being facile, inexpensive and time-saving, can be well adopted to fabricate ordered Cu₂ O nanostructures on the phosphor-copper mesh, thereby providing some guidance for the large-scale practical application of the superhydrophobic structure.（3） Seacucumber-shaped Cu₂ O nanostructure was constructed on phosphor-copper mesh by an one-step simple immersing process in distilled water, with which the preparation was accomplished in distilled water without introducing any other reagent. The phosphor-copper mesh with Cu₂ O structures thereon exhibits great hydrophilicity and induces huge superoleophobic force at the oil/water interface.Interestingly, a “mini boat” made with the as-prepared phosphor-copper mesh can float and move freely on an oil/water interface, and as a smart device it can transport oil and organic liquid underwater without contamination by oil. We anticipate that the as-constructed “mini boat” would help the design of smart aquatic devices that can move freely in an oil/ water system with excellent oil repellent capability, thereby helping oil handling and oil spill cleanup in engineering.（4） Highly dense porous Cu₂ O rods were deposited on commercial phosphor-copper foil by using a distilled water immersion method. After surface modification with 1-dodecanethiol, the phosphor-copperfoil exhibits excellent superhydrophobicity. Interestingly, the wettability of the as-prepared surface can be adjusted from superhydrophobicity to hydrophilicity after store in an oven at 160 ℃ for 30 min, and the resultant phosphor-copper foil can restore its superhydrophobic properties by re-modification with1-dodecanethiol. It was found that numerous disulfide RS-SR bonds were generated on the surface during heating. After rinsing with ethanol, the disulfide RS-SR bonds can be easily removed from the surface,thereby leading to decrease of surface carbon content as well as change of the surface wettability.Hopefully, the present strategy could provide a facile method to fabricate thermal response material and it might find promising application in micro-control and intelligent device fields.