Deposition and super liquid repellency of fluorinated ZnO nanoparticles on carbon fabrics
- 作者：Chien-Te Hsieh ; cthsieh@saturn.yzu.edu.tw ; Dong-Ying Tzou ; Chia-Chen Chen ; Chia-Yi Lai ; Yung-Ying Liu
- 关键词：ZnO nanoparticles ; Water repellency ; Oil repellency ; Contact angle ; Carbon fabric ; Microwave-assisted synthesis
- 刊名：Surface and Coatings Technology
- 出版年：2012
- 期刊代码：106_02578972
- 类别：ms
- 出版时间：25 June, 2012
- 卷：206
- 期：22
- 页码：4639-4644
- 文件大小：696 K
摘要
The liquid-repellent behavior of fluorinated zinc oxide (ZnO) nanoparticles deposited onto carbon fabric (CF) by a pulse microwave-assisted (MA) method followed by surface fluorination treatment was investigated. The MA process is performed at 80 掳C within 10 min with different pH values of 5.5, 8 and 12. The hexagonal ZnO nanoparticles with an average size of 100 nm exhibit a well-defined wurtzite crystal structure without any heat treatment. The ZnO nanoparticles produced by MA synthesis at pH = 8 display the maximal density over CF substrate. The fluorination coating effectively imparts super water and oil repellencies on the ZnO-CF surface; i.e., the contact angles are 163掳 (water) and 153掳 (ethylene glycol, EG). The liquid repellencies toward water and EG droplets show an increasing function of surface density of ZnO nanoparticles. This result can be attributed to the fact that an air layer is confined in the nanoparticles, thereby inducing a rougher gas-vapor-solid contact line, referred to as the Cassie state. Based on the Young-Dupr猫 equation incorporated with the Cassie parameter, the lowest work of adhesion (Wad) values of the ZnO-CF surface for water and EG repellencies are estimated to be 3.16 and 4.93 mJ/m2, respectively. Accordingly, this work sheds some light on the creation of a two-tier texture by an efficient MA route and on how the surface density of ZnO nanoparticles strongly affects the repellent behavior of the resultant ZnO-CF composites.