Effect of surface morphology on wettability conversion

详细信息    查看全文

• 作者：Xia Kong ; Yawei Hu ; Xiaofang Wang ; Wei Pan
• 关键词：TiO2 ; morphology ; wettability ; reverse conversion
• 刊名：Journal of Advanced Ceramics
• 出版年：2016
• 出版时间：December 2016
• 年：2016
• 卷：5
• 期：4
• 页码：284-290
• 全文大小：
• 刊物主题：Ceramics, Glass, Composites, Natural Methods; Characterization and Evaluation of Materials; Nanotechnology; Structural Materials;
• 出版者：Tsinghua University Press
• ISSN：2227-8508
• 卷排序：5

文摘

A hierarchical structural surface of TiO₂ film with reversibly light-switchable wettability between superhydrophobicity and superhydrophilicity on metal substrate was fabricated through simply dip-coating method from TiO₂ precursor solution containing TiO₂ nanoparticles with the average diameter 25 nm (P25), followed by heat-treatment and modification with fluoroalkylsilane (FAS) molecules. The morphology, phase and crystallographic structure, and chemical composite of the as-prepared TiO₂ film were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The wettability of TiO₂ film was characterized by a drop shape analyzer. The water contact angle of superhydrophobic TiO₂ film was up to 165.6°. Under UV irradiation, the water contact angle decreased and the superhydrophobic TiO₂ film became superhydrophilic because of hydroxyl groups absorption on the TiO₂ surface. Meanwhile, the surface morphology of TiO₂ film, which resulted from the TiO₂ nanoparticles added in TiO₂ precursor solution, had a significant effect on the wettability conversion of TiO₂ film and enhanced the switch from hydrophobicity to hydrophilicity. The wettability could be reversibly switched between superhydrophobicity and superhydrophilicity via alternation of UV exposure and dark storage.