纳米粒子构建表面的超疏水性能实验研究

采用疏水纳米粉体压片法和岩心吸附法构建了具有微纳米结构的表面，测试了这些表面的接触角，拍摄了水滴在吸附纳米粒子的岩石表面的滚动过程照片，采用扫描电子显微镜(scanning electron microscope，SEM)检测了表面的微结构.实验结果表明：无机纳米粒子经弱疏水性材料修饰后，其表面润湿性由强亲水变为强疏水；疏水纳米粒子吸附表面的接触角均大于120°，滚动角约7°，显示出超疏水特性；SEM照片显示，这些超疏水表面是具有不规则微纳米结构的气固复合面，符合Cassie-Baxter的复合表面模型. 关键词： 超疏水 纳米粒子 微纳米结构表面 接触角

Experimental investigation of superhydrophobic properties of the surface constructed by nanoparticles

Two kinds of micro- and nano-structural surfaces were constructed with hydrophobic nanoparticles(HNPs)directly. One of the surfaces was formed by compressing the nano powder to a smooth slice, the other was made by adsorbing the nanoparticles on the surface of rock wafer. The contact angles between water drops and the surfaces were measured and the rolling process of a water drop on the nanoparticles-adsorbed rock surface was pictured. The scanning electron microscope(SEM) was used to observe the microstructure of these surfaces also. The results show that the inorganic nanoparticles modified by weak hydrophobic material could have strong hydrophobic property, even though it was strongly hydrophibic initially. The measured contact angles of water drop on the nanoparticle-adsorbed rock surface are always greater than 120°and the rolling angles are less than 7°. These data means that these surfaces are superhydrophobic apparently. The SEM pictures show that these surfaces are air-solid compound interfaces with irregular micro- and nano-structure. It is these special structures that lead to the formation of superhydrophobic surfaces, which are in agreement with the Cassie-Baxter model.