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Dr. Nikos Kehagias Catalan Institute of Nanoscience and Nanotechnology, CSIC and The Barcelona Institute of Science and Technology, Barcelona, Spain Euronanoforum- 21-23 June 2017- Malta

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Page 1: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Dr. Nikos Kehagias

Catalan Institute of Nanoscience and Nanotechnology, CSIC and The Barcelona Institute of Science and Technology,

Barcelona, Spain

Euronanoforum- 21-23 June 2017- Malta

Page 2: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

A

B

C

D

Nanofabrication NanometrologyMaterials

Courtesy of: www.nanotypos.com

Nanotechnology Value Chain

Page 3: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Hybrid

Hierarchical

Nanopatterning

AdvancedNanomanufacturing

R2R Large Area

Functional

Surfaces

Micro/Nano

Injection

Molding

Page 4: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

ICN2 NIL Platform

3 dimensional polymer

structuring

4 mm

Au nanoparticles

35 nm gap

Phononic Crystals400 nm wide nanochannels

200 nm

2D PhC

56 nm

Sub 100 nm Chirped gratings

500 nm

Colloidal crystal growth

Self assemblytemplates

Photonicapplications

Multi levelpatterning

Page 5: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

MARKET OUTLOOK

• Global nano-patterinng market is estimated as US$ 1.9 billion in 2015

- projected to reach US$ 19.1 billion by 2020

• NIL represents 82.9% of the total nano-patterning market

• NIL is estimated as US$ 1.6 billion in 2015 - projected to reach US$

13.9 billion by 2020

• UVNIL fastest growing NIL technology representing 72.8% share of

the market in 2015

• UV-NIL market is estimated at US$ 1.4 billion in 2015 - projected to

reach US$ 12.4 billion in 2020

• Hot embossing market is estimated at US$ 144.2 million in 2015 -

projected to reach US$ 1.3 billion in 2020

Data acquired from Nanopatterning – A global market report- 09/15

Page 6: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Intelligent Surfaces

Page 7: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

DesignMaster

orginationNIL Applications

a

d

+ +

Process Flow

Value chain

Page 8: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Wetting is a multiscale phenomenon

31/ 10/ 13 14.45Biomimetics inspired surfaces for drag reduction and oleophobicity/ philicity

Side 1 af 16http:/ / www.beilstein- journals.org/ bjnano/ single/ art icleFullText.htm?publicId= 2190- 4286- 2- 9

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Abstract

The emerging field of biomimetics allows one to mimic biology or nature to develop nanomaterials, nanodevices,and processes which provide desirable properties. Hierarchical structures with dimensions of features rangingfrom the macroscale to the nanoscale are extremely common in nature and possess properties of interest. Thereare a large number of objects including bacteria, plants, land and aquatic animals, and seashells with propertiesof commercial interest. Certain plant leaves, such as lotus (Nelumbo nucifera) leaves, are known to besuperhydrophobic and self-cleaning due to the hierarchical surface roughness and presence of a wax layer. Inaddition to a self-cleaning effect, these surfaces with a high contact angle and low contact angle hysteresis alsoexhibit low adhesion and drag reduction for fluid flow. An aquatic animal, such as a shark, is another model fromnature for the reduction of drag in fluid flow. The artificial surfaces inspired from the shark skin and lotus leaf havebeen created, and in this article the influence of structure on drag reduction efficiency is reviewed. Biomimetic-inspired oleophobic surfaces can be used to prevent contamination of the underwater parts of ships by biologicaland organic contaminants, including oil. The article also reviews the wetting behavior of oil droplets on varioussuperoleophobic surfaces created in the lab.

Keywords: aquatic animals; biomimetics; drag; lotus plants; shark skin; superhydrophobicity; superoleophobicity

Top

Introduction

Biologically inspired design, adaptation, or derivation from nature is referred to as ‘biomimetics.’ It meansmimicking biology or nature. Nature has gone through evolution over the 3.8 billion years since life is estimated tohave appeared on the Earth [1]. Nature has evolved objects with high performance using commonly foundmaterials. These function on the macroscale to the nanoscale. The understanding of the functions provided byobjects and processes found in nature can guide us to imitate and produce nanomaterials, nanodevices, andprocesses [2]. There are a large number of objects (bacteria, plants, land and aquatic animals, seashells etc.)with properties of commercial interest.

Natural superhydrophobic, self-cleaning, low adhesion, and drag reduction surfaces

Drag reduction in fluid flow is of interest in various commercial applications. These include transportation vehiclesand micro/nanofluidics based biosensor applications [3]. To reduce pressure drop and volume loss inmicro/nanochannels used in micro/nanofluidics, it is desirable to minimize the drag force at the solid–liquidinterface. A model surface for superhydrophobicity, self-cleaning and low adhesion is the leaves of water-repellentplants such as Nelumbo nucifera (lotus) [2,4-11]. The leaf surface is very rough due to so-called papilloseepidermal cells, which form papillae or microasperities. In addition to the microscale roughness, the surface of thepapillae is also rough, with nanoscale asperities composed of three-dimensional epicuticular waxes which arelong chain hydrocarbons and hydrophobic. The waxes on lotus leaves exist as tubules [10,11]. Water droplets onthese hierarchical structured surfaces readily sit on the apex of the nanostructures because air bubbles fill thevalleys of the structure under the droplet (Figure 1a). Therefore, these leaves exhibit considerablesuperhydrophobicity. Static contact angle and contact angle hysteresis of a lotus leaf are about 164° and 3°,respectively [12,13]. The water droplets on the leaves remove any contaminant particles from their surfaces whenthey roll off, leading to self-cleaning [5] and show low adhesive force [14-16].

Natural superoleophobic, self-cleaning, and drag reduction surfaces

A model surface for superoleophobicity and self-cleaning is provided by fish which are known to be well protectedfrom contamination by oil pollution although they are wetted by water [15,17]. Fish scales have a hierarchicalstructure consisting of sector-like scales with diameters of 4–5 mm covered by papillae 100–300 µm in length and30–40 µm in width [18]. Shark skin, which is a model from nature for a low drag surface, is covered by very smallindividual tooth-like scales called dermal denticles (little skin teeth), ribbed with longitudinal grooves (alignedparallel to the local flow direction of the water) (Figure 1b). These grooved scales reduce vortice formation

TABLE OF CONTENTS Detailed

Abstract

Introduction

Fabrication and Characterization ofBiomimetic Structures for Fluid DragReduction

Modeling, Fabrication andCharacterization ofOleophobic/philic Surfaces

Conclusion

References

Show Album

Biomimetics inspired surfaces for drag reduction and oleophobicity/philicity

Bharat Bhushan

Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics (NLB²), The Ohio State University, 201 W.19th Avenue, Columbus, OH 43210-1142, USA

Corresponding author email

This article is part of the Thematic Series "Biomimetic materials".

Guest Editors: W. Barthlott and K. Koch

Beilstein J. Nanotechnol. 2011, 2, 66–84. doi:10.3762/bjnano.2.9

Received 01 Oct 2010 Accepted 20 Jan 2011 Published 01 Feb 2011 Review

ARTICLE INFORMATION

PDF

Download References

PART OF THEMATIC SERIES

Biomimetic materials

Figure 1: Two examples from nature: (a) Lotus effect [12], and (b) scale structure of shark reducing drag [21].

Lotus leaf Rose petal

Self- Cleaning Surfaces

Page 9: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Alternative NIL

REVERSE NIL

Page 10: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Inking mode

Intact modeMicrostructures

UV-NILNanostructures

RNIL

Inking modeIntact mode

Hierarchical patterning

Reverse nanoimprint lithography over pre/patterned surfaces

A. Fernández et.al., Design of hierarchical surfaces for tuning wetting characteristics,B. ACS Applied Materials & Interfaces, (2017) Accepted- Manuscript ID: am-2016-13615t.R1

Page 11: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Self- Cleaning Surfaces

Towards 3D hiearchical surfaces

+

Micro structures Nano structures 3D structures

Page 12: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Contact angles [o]

Theoretical Experimental

Surface Structure Wenzel Cassie-Baxter Static Sliding Hysteresis

Microstructure 111 155 145 ± 4 35 ± 5 16 ± 6

Honeycomb pillars 120 110 118 ± 5 Pinned 30 ± 4

Honeycomb lines 120 155 123 ± 9 Pinned 21 ± 10

Nano pillars 144 134 143 ± 2 Pinned 23 ± 4

Nano spikes 146 ± 3 Pinned 45 ± 5

2D surfaces

Hydrophobic Surfaces

Page 13: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Contact angles [o]

Theoretical Experimental

Surface Structure Wenzel Cassie-Baxter Static Sliding Hysteresis

Honeycomb pillars + Micropillars

138 157 156 ± 3 18 ± 3 12 ± 3

Honeycomb lines + Micropillars

138 171 129 ± 5 17 ± 2 10 ± 3

Nano pillars + Micropillars

180 164 165 ± 1 11 ± 4 7 ± 2

Nano spikes + Micropillars

170 ± 2 7 ± 2 4 ± 2

3D-Hierarchical surfaces

Self- Cleaning Surfaces

Page 14: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Self- Cleaning Surfaces

Page 15: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Self- Cleaning Surfaces

Page 16: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Plast4Future TechnologyEnabeling Functional Plastic

Surfaces

Steel Mold

Mold Nano-Patterning

Injection Molding

Plastic Functional products

Page 17: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

NANO-Injectionmoulding

Courtesy of NILT Aps.

Page 18: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Colour effects

Easy to paint

Superhydrophobic

Indusrtial Applicsations

Page 19: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Injection moulding

PP

Flat WCA 90 ± 3

WCA 150 ± 3

Sliding 16 ± 3

Hysteresis 15 ± 4

TOPAS

Flat WCA 92 ± 2

WCA 152 ± 2

Sliding 13 ± 3

Hysteresis 10 ± 3

66 % WCA Increasing 65 % WCA Increasing

Page 20: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Nanospikes - Micropillars

Impact velocity Wetting state

0 - 0.7 m/s Lotus State: 167 ± 3°

0.7 – 0.9 m/s Petal State: 151 ± 4°

> 0.9 m/s Wenzel State: 117 ± 5°

Nanopillars - Micropillars

Impact velocity Wetting state

0 - 0.8 m/s Lotus State: 168 ± 2°

0.8 – 1.7 m/s Petal State: 156 ± 3°

> 1.7 m/s Wenzel State: 120 ± 6°

Dynamic Surfaces

Page 21: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Oleophobic Surfaces

Liquids with lower surface tension than water → Overhanging

structures needed

A stable Cassie-Baxter state results only when

Concave structure Convex structure

The traction on the liquid-air interface is downwards due to the capillary

force.

Page 22: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Metal deposition Photolithography

or RNILNickel up-plating Resist removal

PDMS ReplicaOrmocomp UV-NILImprinted overhanging

structures

Can be demolded Cannot be demolded

FABRICATION STEPS

Kinoshita et al., Rep. Prog. Phys. (2008)

N. Bogdanski et al. 3D-Hot embossing of undercut structures – an approach to micro-zippers, Microelectronic Engineering 73–74, 190–195, (2004)

Page 23: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Low density:

3 – 3.5 µm

Medium density:

2 – 2.5 µmHigh density:

0.8 – 1 µm

Water contact angles [⁰]

Surface Structure Static Sliding Hysteresis

Flat surface 112 ± 3 35 ± 3 40 ± 6

Low density 148 ± 3 11 ± 4 10 ± 4

Medium density 155 ± 1 8 ± 2 6 ± 3

High density 147 ± 3 15 ± 3 12 ± 5

Oleophobic Surfaces

Page 24: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Roll-to-Roll Nanometrology

PET film

UV light source

Patterned film

InlineNano

Stamp

Page 25: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Stamp

PET film Patterned film

InlineNano

UV light source

Roll-to-Roll at ICN2

Page 26: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

470 nm

430 nm

380 nm

320 nm500 nm

2.5mm

80 mm

20 mm

SEM of a line

470 nm

430 nm

380 nm

320 nm

Line width:

Spacing: 6 µm; Height: 100 nm

Schematics of Silicon Master- A Line Grating -

Page 27: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

InlineNano in MOTION

470nm

430nm

380nm

320nm

Variation in rolling speed:

Line Width:

-> The different line width of the grating can be identified up to a rolling speed of 3.0 m per min.

0 10 20 30 40 50 60 70

4

6

8

10

1.0 m/min

2.0 m/min

3.0 m/min

Inte

ns

ity

(a

.u.)

Y (mm)

Page 28: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

FLEXPOL project (721062)

• 10 partners

– 4 industrialpartners

– 6 researchpartners

• 36 project months(1/2017 – 12/2019)

• 5,678 Mio. EUR total costs

PILOTS-02-2016Pilot Line Manufacturing of Nanostructured AntimicrobialSurfaces using Advanced Nanosurface FuntionalizationTechnologies"

Page 29: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Blown-extrudedpolypropylene

film withencapsulatedantimicrobialessential oil

Antimicrobialfilms

Product validation in laboraty & hospital

Materials processing

& Nanostructuring

FLEXPOL project (721062)

Investigation ofproduct efficiacy in laboratory and real

hospitalenvironment

Surfaces withhierarchicalmicro- and

nanofeaturesinhibitingmicrobes‘

attachment andgrowth

Page 30: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

ACKNOWLEDGMENTS

06/ 04/ 14 18:25Forside - Plast4Future

Page 2 of 2http:/ / www.plast4future.eu/

Partners

http://www.plast4future.eu/ 6 APRIL 2014

Dr. Ariadna FernándezDr. Achille FranconeProf. Clivia Sotomayor Torres

Page 31: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

THANK YOU FOR YOUR ATTENTION

[email protected]

Page 32: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Rose filled microstructure

• In the last years, several new wetting states have been experimentally observed.

• For a hierarchical surface, there can exist nine modes of wetting depending on

whether water penetrates in micro and nanostructures.

• Rose petal effect has a very promising wetting state for different applications,

such as microdroplet transport and localized chemical reactions.

Bhushan, B.; Nosonovsky, M., The rose petal effect and the modes of superhydrophobicity. Philosophical transactions.

Series A 2010, 368 (1929), 4713-28.

Lotus Rose

Cassie Wenzel Wenzel filled microstructure

Cassie filled microstructure Wenzel filled nanostructure Wenzel filled micro/nanostructure

DYNAMIC SURFACES

Page 33: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

Intact mode fabricated surfaces

Static contact angle: 167 ± 3 °

Sliding angle: 7 ± 4 °

Hysteresis: 6 ± 3 °

Static contact angle: 168 ± 2 °

Sliding angle: 6 ± 2 °

Hysteresis: 4 ± 2 °

PMMA

Ormocomp

DYNAMIC SURFACES

Page 34: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

• Dynamic effects on a superhydrophobic surface analyse energy

barriers responsible of wetting transitions.

• These transitions are directly from a composite to a homogeneous

state.

External stimuli

Lotus state Wenzel state

External

stimuliExternal

stimuli

• Hierarchical surfaces open the pathway for intermediate transitions,

which can be useful if one can get a precise control over them.

Lotus stateWenzel state

Petal state

DYNAMIC SURFACES

Page 35: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

M. Nosonovsky et al., Philosophical Transactions of the Royal Society A 374 (2073) (2016).

Extent of gravitational forces relative to capillary

forces acting on the drop

Bond number

LA

glBo

2

Density can induce sagging effect

Liquid Surface Tension(mN/m)

Density(g/m3)

Water 71.99 1

Diiodomethane 50.80 3.32

Ethylene glycol 47.70 1.11

Olive oil 32.03 0.80

30 40 50 60 70

125

130

135

140

145

150

155

Diiodomethane

Ethylene

glycolOlive oil

Water

Co

nta

ct a

ng

le (

0)

Surface Tension (mN/m)

Low density

Medium density

High density

Oleophobic Surfaces

Page 36: Dr. Nikos Kehagias Catalan Institute of Nanoscience and ...euronanoforum2017.eu/.../Session-12-Nikos-Kehagias...Jun 30, 2017  · Dr. Nikos Kehagias Catalan Institute of Nanoscience

0 20 40 60 80 100

20

30

40

50

60

70

80

Su

rfa

ce

te

nsio

n (

mN

/m)

Ethanol concentration (%)

20 30 40 50 60 70 80

60

80

100

120

140

160

Co

nta

ct an

gle

(0)

Surface tension (mN/m)

≈ 29.7 mN/m

Surface tension threshold for oleophobicity

Wetting No wetting

Oleophobic Surfaces