Fabrication And Application Of Superoleophobic Metal Surface

Superoleophobic materials play an important role in many applications, such asanti-pollution, water/oil separation and chemical microreactors. In this dissertation,we used metal material as the substrate. After introduction of micro/nano structureand functional molecule, surfaces with controlled oil wettability and adhesion wereprepared, and related applications such as water/oil separation and microreactionwere also investigated. Main contents can be described as follows:(1) The preparation of superoleophobic aluminum surfaces with controlled oiladhesion and the application in chemical microreactors. Firstly, aluminiumsubstrates were etched in HCl to builded the hierarchical structures, and thenmodification of mixed carboxylic acid (CH3(CH2)6COOH and CF3(CF2)6COOH)molecules. The oil adhesion can be controlled by changing the concentration ofCF3(CF2)6COOH (XF) in the modified solution. The surfaces becomesuperoleophobic as the XFis larger than0.8. The adhesive force between thehexadecane droplet and the surface is decreased as the XFis increased from0.8to1.0. Furthermore, the application of our surfaces in the chemical microreactors wasalso realized.(2) The preparation of underwater superoleophobic copper mesh film byone-step soaking process and the application in oil/water separation. The coppermesh film was immersed into the HS(CH2)11OH ethanol solution, during which,roughness microstructure and hydrophilic group can be formed on the substrate. Theobtained copper mesh film shows good superhydrophilicity, underwatersuperoleophobicity, and oil resistance ability, and these special abilities were stableeven in alkaline or acidic solution. Finally the separation of oil/water mixture wasdemonastrated on the film.(3) The preparation of a pH-responsive superhydrophobic/superhydrophilicand underwater superoleophobic copper mesh film. The film was prepared byassembling responsive thiol molecules HS(CH2)9CH3and HS(CH2)10COOH onto thenanostructured copper mesh substrate, which is superhydrophobic for non-basicwater, whereas superhydrophilic for basic water. Meanwhile, the film also showsunderwater superoleophobicity in basic water. Using the film as a separating membrane, oil/water mixture can be separated according to one’s requirementthrough changing the water pH.