Fabrication And Reseaches Of Superhydrophobic Films On Copper Substrate

Wettability is one of the most important characters of the solid surfaces. It has becomeone of the commonest phenomena in nature and our living. The superhydrophobic surfaceswith special wettability have attracted great attentions for the extensive and potentialapplications on self-cleaning, particulate fluid system, water corrosion resistance andbiology compatibility in our daily life and the industry. The wettability of a solid surface isdecided by the chemical composition and microstructure of the surface geometry, so,superhydrophobic surface is usually produced mainly in two ways. One is to create a roughstructure on a hydrophobic surface, and the other is to modify a rough surface by materialswith low surface free energy. At present, many different ways have been used to fabricateartificial superhydrophobic surface. Unfortunately, due to limitations such as severeconditions, complex process control, special equipment, and poor mechanical performance,this kind of materials are not still used as widely as we expect. So it remains a greatchallenge to find practical and simple methods to prepare superhydrophobic surface onlarge area. In the present dissertation, we have successfully fabricaed the uperhydrophobicthin films based on the theory of the wettability and the superhydrophobic phenomena inthe nature. And their superhydrophobic properties were discussed throughoutly. The contentof this thesis is as following.1. The superhydrophobic surface composed of hierarchical structures weresuccessfully fabricated on the surface of copper by spontaneous deposition and followedanneal. The factors that may affect the morphologies of the copper coating during the wholeprocess and how they work were studied with a series of experiments.2. The surface morphologies, chemical compositions and hydrophobicity of theas-prepared surfaces were investigated using field emission scanning electron microscope,X-ray diffractometer, X-ray photoelectron spectroscopy and contact angle meter.3. The excellent properties of superhydrophobic copper film was investigated by theatmosphere stability test, underwater immersion test, the surface cleaning test, acid andalkali resistance, corrosion resistance and hydrophobic oil testing.The whole process was facile to carry out and did not require organic modification andcomplex equipment, break through the traditional preparation methods. Influences ofetching time, reaction time, PtCl4concentrations, annealing manner, time and temperature, and the kind of solvent on the surface morphologies were presented by analyzing surfacemorphologies and chemical constitutions of the copper coating during the experiment, andthe decisive factor and the optimum condition were found as well. The annealing processplayed a key role.The superhydrophobic surface was composed of hierarchical structures andcharacterized by typical micro-nano coralline-like architectures. At the optimal condition,the surface showed a good superhydrophobicity with a water contact angle of170±2°and asliding angle of approximately0±2°, which belongs to the classical superhydrophobicsurface in Cassie state.The as-prepared superhydrophobic surface exhibited good nonsticking behavior,long-term stability, great corrosion resistance and superoleophobicity, which offerspossibilities to potential applications. It also provides some experimental basis forsuperhydrophobic materials in production applications.