Technical Briefs

Investigations Into Superhydrophobicity of a Soot Surface Attributed to Nano-Asperities

[+] Author and Article Information
N. N. Sharma

e-mail: nitinipun@gmail.com
Department of Mechanical Engineering,
BITS Pilani, Rajasthan 333031, India

1Corresponding author.

Contributed by the Manufacturing Engineering Division of ASME for publication in the JOURNAL OF Micro AND Nano-Manufacturing. Manuscript received April 12, 2012; final manuscript received November 23, 2012; published online March 22, 2013. Assoc. Editor: Ashutosh Sharma.

J. Micro Nano-Manuf 1(1), 014502 (Mar 22, 2013) (3 pages) Paper No: JMNM-12-1023; doi: 10.1115/1.4023288 History: Received April 12, 2012; Revised November 23, 2012

Superhydrophobicity in nature is the result of multiscale (hierarchical) roughness which consists of nano-asperities superimposed on micrometer scale roughness. A low-cost superhydrophobic surface was prepared by depositing soot on Vaseline coated glass substrates. The surface was rapidly prepared without any sophisticated fabrication facilities. The surface exhibited a remarkably high water contact angle of 161 deg and a roll-off angle of 3 deg. Atomic force microscopy (AFM) of the surface was done which revealed a very rough surface. The roughness features with nano-asperities superimposed on micrometer scale roughness enhance the water repellency. The micrometer scale peaks on the surface support the water droplet in a Cassie–Baxter state with the nano-asperities sheltering a composite interface below the droplet. The work of adhesion for the surface was also low at 18 nJ. The study will enable easy preparation of a cost effective superhydrophobic surface.

Copyright © 2013 by ASME
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Fig. 1

Contact angle measurement of a 5 μl drop placed on paraffin entrapped soot surface

Grahic Jump Location
Fig. 2

Contact angle measurement of a 5 μl drop placed on the paraffin wax entrapped soot surface

Grahic Jump Location
Fig. 3

The surface and profile plots from AFM of soot fixed on Vaseline coated substrate. Scan area of 10 μm × 10 μm, which shows the skewness of peaks.

Grahic Jump Location
Fig. 4

The scan area of 1 μm × 1 μm shows a more even distribution of peaks and valleys




Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In