Control of Superhydrophilicity and Superhydrophobicity of a Superwetting Silicon Nanowire Surface
| Autor: | Chie Gau, Cheng Yung Kuo |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Materials science
Polydimethylsiloxane Renewable Energy Sustainability and the Environment Nanowire Nanotechnology Surface finish Thermal treatment Condensed Matter Physics Surfaces Coatings and Films Electronic Optical and Magnetic Materials Contact angle chemistry.chemical_compound chemistry Superhydrophilicity Materials Chemistry Electrochemistry Wetting Dewetting |
| Zdroj: | Journal of The Electrochemical Society. 157:K201 |
| ISSN: | 0013-4651 |
| DOI: | 10.1149/1.3464765 |
| Popis: | The superwetting or dewetting properties of a silicon nanowire (SiNW) surface are studied. The SiNW arrays were grown vertically on SiO 2 or Si substrates by a vapor-liquid-solid process. After a critical length or roughness, the nanowire surface exhibits superhydrophilic property with a contact angle close to 0°. However, the superhydrophilicity of the surface can be transformed into superhydrophobicity by a vacuum treatment, which is a low pressure diffusion process by the vapor from the polydimethylsiloxane material. In addition, the superhydrophobicity of the surface can be readily reversed back to superhydrophilicity by 600°C anneal with N 2 gas flow. The reverse nature of surface wettability can be repeated for many cycles by alternating vacuum with thermal treatment. Physical explanation together with analytical measurements are provided and discussed. The findings have opened a door to completely control the superhydrophilicity or superhydrophobicity of a surface with a very simple and cheap method. |
| Databáze: | OpenAIRE |
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