Nano Archive

Tunable wetting properties of patterned silicon microchannels with varied surface free energy based on layer-by-layer nano self-assembly

Zhang, Tao and Cui, Tianhong (2011) Tunable wetting properties of patterned silicon microchannels with varied surface free energy based on layer-by-layer nano self-assembly. Journal of Micromechanics and Microengineering, 21 (4). 045015.

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Official URL: http://stacks.iop.org/0960-1317/21/i=4/a=045015

Abstract

The wetting properties of patterned silicon microchannels with tunable surface free energy through coating hydrophilic TiO 2 nanoparticles using the layer-by-layer nano self-assembly technique is presented in this paper. The wettability of microchannels is tested by measuring the contact angle of a water droplet on the substrate. The capillary rise rate is tested by measuring the front location of a liquid on the silicon microchannel surface laid on a 45° inclined platform. It is found that the silicon microchannels with tunable surface free energy have super-hydrophilic wettability, and demonstrate a powerful capillary. For the silicon microchannels 200 µm wide, the liquid front can move up 40 mm in approximately 3 s. Fourier transformed infrared spectroscopy and x-ray photoelectron spectroscopy reveal the generation of –OH radicals after coating TiO 2 nanoparticles, verifying that the –OH radicals have a strong effect on the hydrophilicity. The patterned super-hydrophilic microchannels provide potential applications to microfluidic systems and heat diffusion systems based on tunable surface energy.

Item Type:Article
ID Code:11156
Deposited By:Prof. Alexey Ivanov
Deposited On:01 Nov 2011 23:24
Last Modified:02 Nov 2011 00:47

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