| Superhydrophobic nanostructured materials, with a water contact angle (CA) greater than150°, have attracted great attention due to the inspire of "lotus leaf effect" in recent years. In the present work, chosing ZnO and TiO2inorganic material system as raw materials, the different rough-structured nanomaterials were synthesized by studying microstructure and mechanism of all kinds of natural and artificial superhydrophobic surfaces. After the chemical modification by low-surface-energy materials, the change of surface hydrophobility was researched and analyzed systematically to obtain excellent inorganic superhydrophobic nanostructured materials. The main study contents in this dissertation are as follows:1. Hierarchical ZnO flower-like micro/nanospheres assembled by many regular nanosheets were successfully synthesized using low-cost ZnO precursor as the research object through a simple low-temperature aqueous solution route. The morphology, structure, as well as growth mechanism of the product were characterized by all kinds of characterization methods such as X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The photocatalytic performance of the sample was evaluated by the photodegradation of rhodamine B under the UV light, and the results showed that the flower-like ZnO micro/nanospheres exhibit an enhanced photocatalytic performance compared with the other nanostructured ZnO powders. At the same time, the bionic coatings with hydrophobicity were fabricated by the hierarchical ZnO microspheres modified by stearic acid. It was found that the wettability of surfaces was very sensitive to the added amount of stearic acid. The thin films modified with8%stearic acid took on strong superhydrophobicity with a water contact angle (CA) almost to be178°and weak adhersion.2. Superhydrophobic ZnO-nanorod-array film with rough structure was successfully obtained using one-step immersion method in sodium hydroxide solution and subsequent stearic-acid dipping. The resulting surface displayed a water contact angle of157°and roll angle measured at less than5°. In addition, the influence of different stearic acid concentration on the superhydrophobic performance of the film were also discussed. The results showed that the optimum steric acid was0.2g, which would be benefit to obtain superhydrophobic ZnO film in10mL anhydrous alcohol. 3. Using potassium titanium oxalate as raw material, ring-like TiO2-aggregates film deposited on the glass substrate was successfully synthesized by hydrothermal method though a bubble template strategy and ligand exchanging reaction. As chemical modification of1-octadecanethiol or stearic acid, the film took on a good superhydrophobicity. It was found that this property could be attributed to the synergistic effect of the micro/nano-hierarchical structures constructed by many TiO2nanorods or nanoparticles and the formation of self-assembled monolayer with low surface energy.4. The hydrophobility of superhydrophobic ZnO nanomaterials is tested on various substrate materials, which will be benefit to expand to the application of newtype superhydrophobic self-cleaning coating and transparent glass.Figure[46] table[0] reference[93]... |
PDF Full Text Request