Modified Glass And Activated Carbon With Si0₂ Nanoparticles And Their Hydrophobicity

Superhydrophobic surface has many excellent features, such as self-cleaning, anti-fogging, available used for oil-water separation. Performance and preparation of superhydrophobic surface have studied deeply. Recently, putting superhydrophobic technology into production and daily life has becoming a hot spot. This thesis aims to prepare transparent superhydrophobic glass and hydrophobic activated carbon directed by the application of superhydrophobic technology, and investigates its wettability, stability, transparency, and so on.First, we treat the glass sample by mixed acid silica sol with certain percentage, then modifying it with low surface energy organics HDTMS(hexadecyl trimethoxysilane) to prepare a transparent hydrophobic coating. Water contact angle of this transparent hydrophobic coating is 126.5°; transmittance of visible light is up to 96.2%, which increased by 4% compared to bare glass sample. The coating better adhered to the glass substrate and has a stable hydrophobicity. Finally, combined with different surface morphologies of different coatings, we respectively compared the wettability, light transmission, stability and hardness of the coatings prepared by acidic silica sol, alkaline silica sol and different proportion of acid and alkali hybrid solutions.Secondly, we treat the nano silica particles with an ethanol solution of HDTMS for hydrophobic treatment, and then disperse the modified nano silica and ethyl cellulose into ethanol solution used a blending method, using glass as the substrate. We prepared an organic-inorganic nano-composite superhydrophobic coating after pulling the film and modified with HDTMS, whose water contact angle is 153.6°, roll angle is close to 0, visible light transmittance is 92.2%, combined strongly with the substrate, and has a good environmental adaptability.Finally, we prepared a hydrophobic activated carbon with stabled hydrophobic property using a simple one-step solution dipping method and its coarse structure, as well as its adsorption performance of low surface energy organic HDTMS. Water contact angle of the modified hydrophobic activated carbon increased from 56° to 130°, saturated water absorption decreased from 3.04 g to 1.05 g, the amount of dynamical absorption from 1.31 g reduced to 0.06 g, the hydrophobic property increased significantly. In addition, we investigate the effects of different drying temperatures, different drying times and high temperature short time temperature on hydrophobic properties of the activated carbon. The results showed that the activated carbon has a stabled hydrophobic property, and it resolved many problems, such as activated carbon prone to have fungus and mildew, and the adsorption capacity of target organisms reduced in high humidity environment. The preparation process is simple, the experimental condition is mild, and the prepared activate carbon has a good stabled hydrophobic property, good reproducibility, and good environmental compatibility.