Reversible UV-Light-Induced Ultrahydrophobic-to-Ultrahydrophilic Transition in an α-Fe2O3 Nanoflakes Film

• Published in: Langmuir Vol. 24; no. 19; pp. 10569 - 10571
• Main Authors: Yan, Bin, Tao, Junguang, Pang, Christina, Zheng, Zhe, Shen, Zexiang, Huan, Cheng Hon Alfred, Yu, Ting
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 07.10.2008
• Subjects: Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Photochemistry; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Surface physical chemistry; Binary compound; Wetting; Film; Device; Photocatalysis; Transition element compounds; Nanostructure; X ray; Hydrophobicity; Wettability; Adsorption; Surface defect; Photoelectron spectrometry
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la801900r

We describe a simple and robust approach to fabricating an α-Fe2O3 switchable surface. The hydrophobicity of α-Fe2O3 nanostructures was observed for the first time. A remarkable surface wettability transition can be easily achieved by ultraviolet (UV) illumination. The distinctive properties of surface defects are disclosed by X-ray photoelectron spectroscopy (XPS) analysis. The nanoscale adsorption and photocatalytic properties of Fe2+ defects account for the highly amphiphilic character of the surfaces. We believe that the experiment will further the molecular-scale understanding and manipulation of the wetting behavior on smart devices.