1 supplementry information superhydrophobic coating buoyancy … · 1 1 supplementry information 2...
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1 Supplementry information
2 Buoyancy increase and drag-reduction through a simple
3 superhydrophobic coating4 Gi Byoung Hwang a, Adnan Patir a, Kristopher Page a, Yao Lu a, Elaine Allan b and Ivan P. 5 Parkin a*
6 aMaterials Chemistry Research Centre, Department of Chemistry, University College
7 London, 20 Gordon Street, London, WC1H 0AJ, United Kingdom
8 bDivision of Microbial Diseases, UCL Eastman Dental Institute, University College London,
9 256 Gray’s Inn Road, London WC1X 8LD, United Kingdom
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20 * To whom correspondence should be addressed.
21 E-mail: [email protected] Tel: 44(0)207 679 4669
Electronic Supplementary Material (ESI) for Nanoscale.This journal is © The Royal Society of Chemistry 2017
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22 Table S1. Loading weight and downforce edge-, top- and whole surface-coated samples 23 floating on water
Sample Loading weight (mg/cm2)
Downforce by weight (mN)
Edge-coated glass slide 160 31
Top coated glass slide 200 39
Whole surface coated glass slide 319 62
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26 Figure S1. Water repellent and tests of untreated TiO2 and PFOTES treated TiO2 particles.
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30 Fig. S2. Schematic illustration of (a) edge-, (b) top-, and (c) whole surface-coated glass 31 samples floating on water
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38 As shown in Fig. S3 (a), the falling speed of the treated sample was slower than that of the 39 untreated sample. This can be explained in that upward force (buoyancy) of significant 40 amount of air bubbles entrapped (Fig. S3 (b)) on superhydrophbic surface retarded falling of 41 the glass sample.
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44 Fig. S3. (a) Photographs of untreated and bottom coated glass slides falling in water, and (b) 45 plastron property of air bubble layer trapped on the treated surface in water
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51 Fig. S4. (a) Schematic illustration of edged coated sample floating on water after the loading 52 of 3.2 g weight (b) the illustration of sinking process of the sample after the loading of > 3.2 53 g weight.
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68 Fig. S5. Supporting forces (water surface tension and micro air bubbles) applied to whole 69 surface-coated samples.
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73 Fig. S6. Illustration of shipping test
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78 Fig. S7. Abrasion test of (a) superhydrophobic coated glass slide and (b) boat using sand 79 paper
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