Science - USA (2021-07-16)

Such surfaces can appreciably reduce the
solid-ice contact area and, thereby, display
^tice~40kPa(Fig.5A)( 15 , 58 ). However, such
low^ticevaluesareonlyobtainedwheniceis
frozen from water that was in the Cassie-Baxter

state ( 12 ). Low^ticevalues cannot be maintained

if ice formation is preceded by the infiltration of

water within the surface texture, such as during

frost formation, which substantially increases

the ice-solid interfacial area ( 12 ).

Broadly, surface texture, though advanta-

geous in many cases for the reduction of liquid

fouling as discussed previously, can increase the

adhesion of a range of different solid foulants

besides ice, including scale ( 64 ), and various

Dhyaniet al.,Science 373 , eaba5010 (2021) 16 July 2021 6 of 13

Fig. 4. Design of surfaces to reduce solid fouling.(A) The variation in the

length scale of fouling, and the foulant modulus, for different common

solid foulants. (B) Low-solid-adhesion surface design guide, indicating the

range of foulant elastic modulus and length scale over which seven prominent

surface design strategies have been successful in reducing fouling.“Optimize

Surface Energy”inset redrawn based on ( 54 ).“High Surface Mobility”inset

image adapted with permission from ( 159 ), copyright the American Chemical

Society (1997).“Textured”inset image adapted with permission from

( 66 ), copyright WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim (1997).

“Hygro-responsive”inset image adapted from ( 112 ) with permission from

https://creativecommons.org/licenses/by-nc-nd/3.0/.“Crack Promotion”inset

image reprinted from ( 59 ).“Minimize Surface Modulus”inset image adapted from

( 63 ) with permission fromhttps://creativecommons.org/licenses/by/4.0/.

“SLIPS”inset image adapted from ( 68 ) with permission. (C) Performance of

antifouling surfaces across five representative foulants of varying moduli:

Bacteria ( 68 , 110 , 160 – 164 ), Algae ( 81 , 165 – 172 ), Barnacles ( 70 , 169 , 172 – 177 ),

Glaze Ice ( 9 , 38 , 58 , 59 , 62 , 73 , 74 , 76 , 84 – 86 , 90 ), and Inorganic Scale

( 64 , 71 , 161 , 178 – 181 ). Literature data were sorted according to the surface

design aspect that dominated in contributing to the surface’s performance. For

surfaces where two design aspects contributed appreciably to performance,

split color markers are used to indicate both approaches. Literature reports

were only included in this plot if performance data were reported alongside control

data for one of a select number of common control surfaces (listed on the plot).

Surface performance is reported using a particular performance matrix for

each foulant (amount of adhered bacteria, percentage of adhered algae

remaining after shear flow, barnacle adhesion strength, ice adhesion strength

or mass gain after extended exposure to a scaling solution) to ensure that

all values are comparable.

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