How nanorough is rough enough to make a surface superhydrophobic during water condensation?

Konrad Rykaczewski, William A. Osborn, Jeff Chinn, Marlon L. Walker, John Henry J Scott, Wanda Jones, Chonglei Hao, Shuhuai Yao, Zuankai Wang

Research output: Contribution to journalArticle

123 Citations (Scopus)

Abstract

Nanostructured surfaces which manifest superhydrophobic properties during water condensation have a potential to dramatically enhance energy efficiency in power generation and desalination systems. Although various such surfaces have been reported, their development has been fortuitous, not driven by an understanding of the underlying physical processes. In this work, we perform a comprehensive study of microscale water condensation dynamics on nanostructured superhydrophobic surfaces made using a variety of synthetic methods. We demonstrate that the growth mechanism of individual water microdroplets on these surfaces is universal and independent of the surface architecture. The key role of the nanoscale topography is confinement of the base area of forming droplets, which allows droplets to grow only through contact angle increase. The nearly spherical droplets formed in this fashion become highly mobile after coalescence. By comparing experimentally observed drop growth with interface free energy calculations, we show that the minimum observed confined microdroplet base diameter depends directly on the nanoscale surface roughness and degree of interfacial wetting. Specifically, we show that the microscale condensation mechanism depends on the height of a liquid film with volume equal to the fill volume between the nanostructures. This introduced roughness length scale is a universal metric that allows for facile comparison of arbitrarily complex surface architectures. We use this new fundamental insight to develop quantitative design guidelines for superhydrophobic surfaces intended for condensation applications. This journal is

Original languageEnglish (US)
Pages (from-to)8786-8794
Number of pages9
JournalSoft Matter
Volume8
Issue number33
DOIs
StatePublished - Sep 7 2012
Externally publishedYes

Fingerprint

Condensation
condensation
Water
water
microbalances
Surface roughness
Liquid films
Desalination
Coalescence
Topography
coalescing
Free energy
wetting
Contact angle
Power generation
Energy efficiency
Wetting
Nanostructures
topography
surface roughness

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics

Cite this

Rykaczewski, K., Osborn, W. A., Chinn, J., Walker, M. L., Scott, J. H. J., Jones, W., ... Wang, Z. (2012). How nanorough is rough enough to make a surface superhydrophobic during water condensation? Soft Matter, 8(33), 8786-8794. https://doi.org/10.1039/c2sm25502b

How nanorough is rough enough to make a surface superhydrophobic during water condensation? / Rykaczewski, Konrad; Osborn, William A.; Chinn, Jeff; Walker, Marlon L.; Scott, John Henry J; Jones, Wanda; Hao, Chonglei; Yao, Shuhuai; Wang, Zuankai.

In: Soft Matter, Vol. 8, No. 33, 07.09.2012, p. 8786-8794.

Research output: Contribution to journalArticle

Rykaczewski, K, Osborn, WA, Chinn, J, Walker, ML, Scott, JHJ, Jones, W, Hao, C, Yao, S & Wang, Z 2012, 'How nanorough is rough enough to make a surface superhydrophobic during water condensation?', Soft Matter, vol. 8, no. 33, pp. 8786-8794. https://doi.org/10.1039/c2sm25502b
Rykaczewski, Konrad ; Osborn, William A. ; Chinn, Jeff ; Walker, Marlon L. ; Scott, John Henry J ; Jones, Wanda ; Hao, Chonglei ; Yao, Shuhuai ; Wang, Zuankai. / How nanorough is rough enough to make a surface superhydrophobic during water condensation?. In: Soft Matter. 2012 ; Vol. 8, No. 33. pp. 8786-8794.
@article{3549c8ee83df4c698159b6b10d2b3f2a,
title = "How nanorough is rough enough to make a surface superhydrophobic during water condensation?",
abstract = "Nanostructured surfaces which manifest superhydrophobic properties during water condensation have a potential to dramatically enhance energy efficiency in power generation and desalination systems. Although various such surfaces have been reported, their development has been fortuitous, not driven by an understanding of the underlying physical processes. In this work, we perform a comprehensive study of microscale water condensation dynamics on nanostructured superhydrophobic surfaces made using a variety of synthetic methods. We demonstrate that the growth mechanism of individual water microdroplets on these surfaces is universal and independent of the surface architecture. The key role of the nanoscale topography is confinement of the base area of forming droplets, which allows droplets to grow only through contact angle increase. The nearly spherical droplets formed in this fashion become highly mobile after coalescence. By comparing experimentally observed drop growth with interface free energy calculations, we show that the minimum observed confined microdroplet base diameter depends directly on the nanoscale surface roughness and degree of interfacial wetting. Specifically, we show that the microscale condensation mechanism depends on the height of a liquid film with volume equal to the fill volume between the nanostructures. This introduced roughness length scale is a universal metric that allows for facile comparison of arbitrarily complex surface architectures. We use this new fundamental insight to develop quantitative design guidelines for superhydrophobic surfaces intended for condensation applications. This journal is",
author = "Konrad Rykaczewski and Osborn, {William A.} and Jeff Chinn and Walker, {Marlon L.} and Scott, {John Henry J} and Wanda Jones and Chonglei Hao and Shuhuai Yao and Zuankai Wang",
year = "2012",
month = "9",
day = "7",
doi = "10.1039/c2sm25502b",
language = "English (US)",
volume = "8",
pages = "8786--8794",
journal = "Soft Matter",
issn = "1744-683X",
publisher = "Royal Society of Chemistry",
number = "33",

}

TY - JOUR

T1 - How nanorough is rough enough to make a surface superhydrophobic during water condensation?

AU - Rykaczewski, Konrad

AU - Osborn, William A.

AU - Chinn, Jeff

AU - Walker, Marlon L.

AU - Scott, John Henry J

AU - Jones, Wanda

AU - Hao, Chonglei

AU - Yao, Shuhuai

AU - Wang, Zuankai

PY - 2012/9/7

Y1 - 2012/9/7

N2 - Nanostructured surfaces which manifest superhydrophobic properties during water condensation have a potential to dramatically enhance energy efficiency in power generation and desalination systems. Although various such surfaces have been reported, their development has been fortuitous, not driven by an understanding of the underlying physical processes. In this work, we perform a comprehensive study of microscale water condensation dynamics on nanostructured superhydrophobic surfaces made using a variety of synthetic methods. We demonstrate that the growth mechanism of individual water microdroplets on these surfaces is universal and independent of the surface architecture. The key role of the nanoscale topography is confinement of the base area of forming droplets, which allows droplets to grow only through contact angle increase. The nearly spherical droplets formed in this fashion become highly mobile after coalescence. By comparing experimentally observed drop growth with interface free energy calculations, we show that the minimum observed confined microdroplet base diameter depends directly on the nanoscale surface roughness and degree of interfacial wetting. Specifically, we show that the microscale condensation mechanism depends on the height of a liquid film with volume equal to the fill volume between the nanostructures. This introduced roughness length scale is a universal metric that allows for facile comparison of arbitrarily complex surface architectures. We use this new fundamental insight to develop quantitative design guidelines for superhydrophobic surfaces intended for condensation applications. This journal is

AB - Nanostructured surfaces which manifest superhydrophobic properties during water condensation have a potential to dramatically enhance energy efficiency in power generation and desalination systems. Although various such surfaces have been reported, their development has been fortuitous, not driven by an understanding of the underlying physical processes. In this work, we perform a comprehensive study of microscale water condensation dynamics on nanostructured superhydrophobic surfaces made using a variety of synthetic methods. We demonstrate that the growth mechanism of individual water microdroplets on these surfaces is universal and independent of the surface architecture. The key role of the nanoscale topography is confinement of the base area of forming droplets, which allows droplets to grow only through contact angle increase. The nearly spherical droplets formed in this fashion become highly mobile after coalescence. By comparing experimentally observed drop growth with interface free energy calculations, we show that the minimum observed confined microdroplet base diameter depends directly on the nanoscale surface roughness and degree of interfacial wetting. Specifically, we show that the microscale condensation mechanism depends on the height of a liquid film with volume equal to the fill volume between the nanostructures. This introduced roughness length scale is a universal metric that allows for facile comparison of arbitrarily complex surface architectures. We use this new fundamental insight to develop quantitative design guidelines for superhydrophobic surfaces intended for condensation applications. This journal is

UR - http://www.scopus.com/inward/record.url?scp=84864682268&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84864682268&partnerID=8YFLogxK

U2 - 10.1039/c2sm25502b

DO - 10.1039/c2sm25502b

M3 - Article

VL - 8

SP - 8786

EP - 8794

JO - Soft Matter

JF - Soft Matter

SN - 1744-683X

IS - 33

ER -