Abstract

This work is inspired by biological nanostructured surfaces possessing structural color generation and wettability control. Nanostructured films consisting of a tantalum pentoxide (Ta2O5) nanopost array (nanograss) formed on top of a continuous Ta2O5 layer on a reflective Ta thin-film have been fabricated and investigated. A non-iridescent coloration typical for short-range order was produced by the nanograss while iridescent coloration was produced by the underlying continuous Ta2O5 layer. When the nanograss surface is wetted with organic liquids, a different non-iridescent blue color appears. Moreover, this blue color can be dynamically and reversibly switched on and off by applying electrical current to an indium-tin-oxide electrode.

© 2014 Optical Society of America

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References

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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]

2012

S. Manakasettharn, T. H. Hsu, G. Myhre, S. Pau, J. A. Taylor, and T. Krupenkin, “Transparent and superhydrophobic Ta2O5 nanostructured thin films,” Opt. Mater. Express2(2), 214–221 (2012).
[CrossRef]

B. Scheid, E. A. van Nierop, and H. A. Stone, “Thermocapillary-assisted pulling of contact-free liquid films,” Phys. Fluids24(3), 032107 (2012).
[CrossRef]

H. Chraïbi and J. P. Delville, “Thermocapillary flows and interface deformations produced by localized laser heating in confined environment,” Phys. Fluids24(3), 032102 (2012).
[CrossRef]

2010

A. A. Darhuber, J. P. Valentino, and S. M. Troian, “Planar digital nanoliter dispensing system based on thermocapillary actuation,” Lab Chip10(8), 1061–1071 (2010).
[CrossRef] [PubMed]

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

2009

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

2008

Z. Jiao, X. Huang, N. T. Nguyen, and P. Abgrall, “Thermocapillary actuation of droplet in a planar microchannel,” Microfluidics and Nanofluidics5(2), 205–214 (2008).
[CrossRef]

2007

Y. Zheng, X. Gao, and L. Jiang, “Directional adhesion of superhydrophobic butterfly wings,” Soft Matter3(2), 178–182 (2007).
[CrossRef]

X. Q. Feng, X. Gao, Z. Wu, L. Jiang, and Q. S. Zheng, “Superior water repellency of water strider legs with hierarchical structures: experiments and analysis,” Langmuir23(9), 4892–4896 (2007).
[CrossRef] [PubMed]

2005

J. Z. Chen, S. M. Troian, A. A. Darhuber, and S. Wagner, “Effect of contact angle hysteresis on thermocapillary droplet actuation,” J. Appl. Phys.97(1), 014906 (2005).
[CrossRef]

2004

X. Gao and L. Jiang, “Biophysics: water-repellent legs of water striders,” Nature432(7013), 36 (2004).
[CrossRef] [PubMed]

2003

R. O. Prum and R. H. Torres, “A Fourier Tool for the Analysis of Coherent Light Scattering by Bio-Optical Nanostructures,” Integr. Comp. Biol.43(4), 591–602 (2003).
[CrossRef] [PubMed]

2001

A. R. Parker and C. R. Lawrence, “Water capture by a desert beetle,” Nature414(6859), 33–34 (2001).
[CrossRef] [PubMed]

1998

I. Marchuk and O. Kabov, “Numerical modeling of thermocapillary reverse flow in thin liquid films under local heating,” Russ.J.Eng.Thermophys8, 17–46 (1998).

1993

1980

S. M. Pimputkar and S. Ostrach, “Transient thermocapillary flow in thin liquid layers,” Phys. Fluids23(7), 1281 (1980).
[CrossRef]

Abgrall, P.

Z. Jiao, X. Huang, N. T. Nguyen, and P. Abgrall, “Thermocapillary actuation of droplet in a planar microchannel,” Microfluidics and Nanofluidics5(2), 205–214 (2008).
[CrossRef]

Cao, H.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

Chen, J. Z.

J. Z. Chen, S. M. Troian, A. A. Darhuber, and S. Wagner, “Effect of contact angle hysteresis on thermocapillary droplet actuation,” J. Appl. Phys.97(1), 014906 (2005).
[CrossRef]

Chraïbi, H.

H. Chraïbi and J. P. Delville, “Thermocapillary flows and interface deformations produced by localized laser heating in confined environment,” Phys. Fluids24(3), 032102 (2012).
[CrossRef]

Costa, G. D.

Darhuber, A. A.

A. A. Darhuber, J. P. Valentino, and S. M. Troian, “Planar digital nanoliter dispensing system based on thermocapillary actuation,” Lab Chip10(8), 1061–1071 (2010).
[CrossRef] [PubMed]

J. Z. Chen, S. M. Troian, A. A. Darhuber, and S. Wagner, “Effect of contact angle hysteresis on thermocapillary droplet actuation,” J. Appl. Phys.97(1), 014906 (2005).
[CrossRef]

Delville, J. P.

H. Chraïbi and J. P. Delville, “Thermocapillary flows and interface deformations produced by localized laser heating in confined environment,” Phys. Fluids24(3), 032102 (2012).
[CrossRef]

Dufresne, E. R.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

Feng, X. Q.

X. Q. Feng, X. Gao, Z. Wu, L. Jiang, and Q. S. Zheng, “Superior water repellency of water strider legs with hierarchical structures: experiments and analysis,” Langmuir23(9), 4892–4896 (2007).
[CrossRef] [PubMed]

Gao, X.

X. Q. Feng, X. Gao, Z. Wu, L. Jiang, and Q. S. Zheng, “Superior water repellency of water strider legs with hierarchical structures: experiments and analysis,” Langmuir23(9), 4892–4896 (2007).
[CrossRef] [PubMed]

Y. Zheng, X. Gao, and L. Jiang, “Directional adhesion of superhydrophobic butterfly wings,” Soft Matter3(2), 178–182 (2007).
[CrossRef]

X. Gao and L. Jiang, “Biophysics: water-repellent legs of water striders,” Nature432(7013), 36 (2004).
[CrossRef] [PubMed]

Hsu, T. H.

Huang, X.

Z. Jiao, X. Huang, N. T. Nguyen, and P. Abgrall, “Thermocapillary actuation of droplet in a planar microchannel,” Microfluidics and Nanofluidics5(2), 205–214 (2008).
[CrossRef]

Jiang, L.

X. Q. Feng, X. Gao, Z. Wu, L. Jiang, and Q. S. Zheng, “Superior water repellency of water strider legs with hierarchical structures: experiments and analysis,” Langmuir23(9), 4892–4896 (2007).
[CrossRef] [PubMed]

Y. Zheng, X. Gao, and L. Jiang, “Directional adhesion of superhydrophobic butterfly wings,” Soft Matter3(2), 178–182 (2007).
[CrossRef]

X. Gao and L. Jiang, “Biophysics: water-repellent legs of water striders,” Nature432(7013), 36 (2004).
[CrossRef] [PubMed]

Jiao, Z.

Z. Jiao, X. Huang, N. T. Nguyen, and P. Abgrall, “Thermocapillary actuation of droplet in a planar microchannel,” Microfluidics and Nanofluidics5(2), 205–214 (2008).
[CrossRef]

Kabov, O.

I. Marchuk and O. Kabov, “Numerical modeling of thermocapillary reverse flow in thin liquid films under local heating,” Russ.J.Eng.Thermophys8, 17–46 (1998).

Krupenkin, T.

Lawrence, C. R.

A. R. Parker and C. R. Lawrence, “Water capture by a desert beetle,” Nature414(6859), 33–34 (2001).
[CrossRef] [PubMed]

Liew, S. F.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

Manakasettharn, S.

Marchuk, I.

I. Marchuk and O. Kabov, “Numerical modeling of thermocapillary reverse flow in thin liquid films under local heating,” Russ.J.Eng.Thermophys8, 17–46 (1998).

Mochrie, S. G.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

Myhre, G.

Nguyen, N. T.

Z. Jiao, X. Huang, N. T. Nguyen, and P. Abgrall, “Thermocapillary actuation of droplet in a planar microchannel,” Microfluidics and Nanofluidics5(2), 205–214 (2008).
[CrossRef]

Noh, H.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

Ostrach, S.

S. M. Pimputkar and S. Ostrach, “Transient thermocapillary flow in thin liquid layers,” Phys. Fluids23(7), 1281 (1980).
[CrossRef]

Parker, A. R.

A. R. Parker and C. R. Lawrence, “Water capture by a desert beetle,” Nature414(6859), 33–34 (2001).
[CrossRef] [PubMed]

Pau, S.

Pimputkar, S. M.

S. M. Pimputkar and S. Ostrach, “Transient thermocapillary flow in thin liquid layers,” Phys. Fluids23(7), 1281 (1980).
[CrossRef]

Prum, R. O.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

R. O. Prum and R. H. Torres, “A Fourier Tool for the Analysis of Coherent Light Scattering by Bio-Optical Nanostructures,” Integr. Comp. Biol.43(4), 591–602 (2003).
[CrossRef] [PubMed]

Saranathan, V.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

Scheid, B.

B. Scheid, E. A. van Nierop, and H. A. Stone, “Thermocapillary-assisted pulling of contact-free liquid films,” Phys. Fluids24(3), 032107 (2012).
[CrossRef]

Stone, H. A.

B. Scheid, E. A. van Nierop, and H. A. Stone, “Thermocapillary-assisted pulling of contact-free liquid films,” Phys. Fluids24(3), 032107 (2012).
[CrossRef]

Taylor, J. A.

Torres, R. H.

R. O. Prum and R. H. Torres, “A Fourier Tool for the Analysis of Coherent Light Scattering by Bio-Optical Nanostructures,” Integr. Comp. Biol.43(4), 591–602 (2003).
[CrossRef] [PubMed]

Troian, S. M.

A. A. Darhuber, J. P. Valentino, and S. M. Troian, “Planar digital nanoliter dispensing system based on thermocapillary actuation,” Lab Chip10(8), 1061–1071 (2010).
[CrossRef] [PubMed]

J. Z. Chen, S. M. Troian, A. A. Darhuber, and S. Wagner, “Effect of contact angle hysteresis on thermocapillary droplet actuation,” J. Appl. Phys.97(1), 014906 (2005).
[CrossRef]

Valentino, J. P.

A. A. Darhuber, J. P. Valentino, and S. M. Troian, “Planar digital nanoliter dispensing system based on thermocapillary actuation,” Lab Chip10(8), 1061–1071 (2010).
[CrossRef] [PubMed]

van Nierop, E. A.

B. Scheid, E. A. van Nierop, and H. A. Stone, “Thermocapillary-assisted pulling of contact-free liquid films,” Phys. Fluids24(3), 032107 (2012).
[CrossRef]

Wagner, S.

J. Z. Chen, S. M. Troian, A. A. Darhuber, and S. Wagner, “Effect of contact angle hysteresis on thermocapillary droplet actuation,” J. Appl. Phys.97(1), 014906 (2005).
[CrossRef]

Wu, Z.

X. Q. Feng, X. Gao, Z. Wu, L. Jiang, and Q. S. Zheng, “Superior water repellency of water strider legs with hierarchical structures: experiments and analysis,” Langmuir23(9), 4892–4896 (2007).
[CrossRef] [PubMed]

Zheng, Q. S.

X. Q. Feng, X. Gao, Z. Wu, L. Jiang, and Q. S. Zheng, “Superior water repellency of water strider legs with hierarchical structures: experiments and analysis,” Langmuir23(9), 4892–4896 (2007).
[CrossRef] [PubMed]

Zheng, Y.

Y. Zheng, X. Gao, and L. Jiang, “Directional adhesion of superhydrophobic butterfly wings,” Soft Matter3(2), 178–182 (2007).
[CrossRef]

Adv. Mater.

H. Noh, S. F. Liew, V. Saranathan, S. G. Mochrie, R. O. Prum, E. R. Dufresne, and H. Cao, “How Noniridescent Colors Are Generated by Quasi-Ordered Structures of Bird Feathers,” Adv. Mater.22(26-27), 2871–2880 (2010).
[CrossRef] [PubMed]

Appl. Opt.

Integr. Comp. Biol.

R. O. Prum and R. H. Torres, “A Fourier Tool for the Analysis of Coherent Light Scattering by Bio-Optical Nanostructures,” Integr. Comp. Biol.43(4), 591–602 (2003).
[CrossRef] [PubMed]

J. Appl. Phys.

J. Z. Chen, S. M. Troian, A. A. Darhuber, and S. Wagner, “Effect of contact angle hysteresis on thermocapillary droplet actuation,” J. Appl. Phys.97(1), 014906 (2005).
[CrossRef]

Lab Chip

A. A. Darhuber, J. P. Valentino, and S. M. Troian, “Planar digital nanoliter dispensing system based on thermocapillary actuation,” Lab Chip10(8), 1061–1071 (2010).
[CrossRef] [PubMed]

Langmuir

X. Q. Feng, X. Gao, Z. Wu, L. Jiang, and Q. S. Zheng, “Superior water repellency of water strider legs with hierarchical structures: experiments and analysis,” Langmuir23(9), 4892–4896 (2007).
[CrossRef] [PubMed]

Microfluidics and Nanofluidics

Z. Jiao, X. Huang, N. T. Nguyen, and P. Abgrall, “Thermocapillary actuation of droplet in a planar microchannel,” Microfluidics and Nanofluidics5(2), 205–214 (2008).
[CrossRef]

Nature

A. R. Parker and C. R. Lawrence, “Water capture by a desert beetle,” Nature414(6859), 33–34 (2001).
[CrossRef] [PubMed]

X. Gao and L. Jiang, “Biophysics: water-repellent legs of water striders,” Nature432(7013), 36 (2004).
[CrossRef] [PubMed]

Opt. Mater. Express

Phys. Fluids

B. Scheid, E. A. van Nierop, and H. A. Stone, “Thermocapillary-assisted pulling of contact-free liquid films,” Phys. Fluids24(3), 032107 (2012).
[CrossRef]

H. Chraïbi and J. P. Delville, “Thermocapillary flows and interface deformations produced by localized laser heating in confined environment,” Phys. Fluids24(3), 032102 (2012).
[CrossRef]

S. M. Pimputkar and S. Ostrach, “Transient thermocapillary flow in thin liquid layers,” Phys. Fluids23(7), 1281 (1980).
[CrossRef]

Russ.J.Eng.Thermophys

I. Marchuk and O. Kabov, “Numerical modeling of thermocapillary reverse flow in thin liquid films under local heating,” Russ.J.Eng.Thermophys8, 17–46 (1998).

Soft Matter

E. R. Dufresne, H. Noh, V. Saranathan, S. G. Mochrie, H. Cao, and R. O. Prum, “Self-assembly of amorphous biophotonic nanostructures by phase separation,” Soft Matter5(9), 1792–1795 (2009).
[CrossRef]

Y. Zheng, X. Gao, and L. Jiang, “Directional adhesion of superhydrophobic butterfly wings,” Soft Matter3(2), 178–182 (2007).
[CrossRef]

Other

S. Wolfram, The MATHEMATICA® Book, Version 4 (Cambridge University Press, 1999).

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Figures (5)

Fig. 1
Fig. 1

(a) Schematic illustrating the structure of the nanostructured thin film and the interaction of light at its surface: thin film interference from the continuous Ta2O5 layer and scattering by the Ta2O5 nanograss. (b) SEM cross-section image of the nanograss structure. (c) Top view optical image of yellow nanograss structure. (d)Top view SEM image of the Ta2O5 nanograss. (e) Optical image of methanol spot on the Ta2O5 nanograss substrate in ambient light. (f) Top view optical image of methanol spot taken with direct illumination by the fiber optic light. (g) Optical image of methanol spot taken at 30° with respect to normal to the surface, under direct illumination by the fiber optic light..

Fig. 2
Fig. 2

Measured reflectance spectra of a planar Ta2O5 film, dry Ta2O5 nanograss, and the blue spots created by wetting the nanograss with various organic liquids (methanol, ethanol, IPA, acetone, toluene, and chloroform). The reflectance spectra were taken at 30° with respect to the normal to the surface.

Fig. 3
Fig. 3

(a) 2D DFT of the Ta2O5 nanograss (shown in Fig. 1(d)). (b) Radial average of the power spectrum. (c) Scattered spectra (dots) predicted from the Fourier analysis of the SEM image (Fig. 1(d)); dashed lines used for guiding. (d) Scattering spectra obtained from the reflectance measurements.

Fig. 4
Fig. 4

(a) The predicted scattered spectrum (green) of the dry nanograss film and the measured reflectance spectrum (black) of the planar Ta2O5 thin-film stack. (b) The measured (orange) and predicted (green) reflectance spectra of the Ta2O5 nanograss. (c) The predicted scattered spectrum (intense blue) of the blue spot and the measured reflectance spectrum (black) of the planar Ta2O5 thin-film stack. (d) The measured (light blue) and predicted (dark blue) reflectance spectra of the wet blue spot of methanol on Ta2O5 nanograss.

Fig. 5
Fig. 5

(a) Electrically-induced switching of the methanol-induced coloration. (b) Schematics illustrating how the methanol distribution inside the nanograss layer changes when the electric current applied to an ITO electrode is switched off and on.

Equations (2)

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R o = R i ( 1 R s ) 2
R s = [ tan h ( λ / d ) 2 ] [ a + b e ( ( λ f ) / c ) 2 ]

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