TY - JOUR
T1 - Extreme Antiscaling Performance of Slippery Omniphobic Covalently Attached Liquids
AU - Zhao, Hanyang
AU - Deshpande, Chirag Anand
AU - Li, Longnan
AU - Yan, Xiao
AU - Hoque, Muhammad Jahidul
AU - Kuntumalla, Gowtham
AU - Rajagopal, Manjunath C.
AU - Chang, Ho Chan
AU - Meng, Yuquan
AU - Sundar, Sreenath
AU - Ferreira, Placid
AU - Shao, Chenhui
AU - Salapaka, Srinivasa
AU - Sinha, Sanjiv
AU - Miljkovic, Nenad
N1 - Funding Information:
We acknowledge support from the Advanced Manufacturing Office (AMO) of the Office of Energy Efficiency and Renewable Energy (EERE) under the U.S. Department of Energy, through the grant DE-EE0008312. The authors gratefully acknowledge funding support from the Air Conditioning and Refrigeration Center (ACRC), an NSF founded I/UCRC at UIUC. N.M. gratefully acknowledges funding support from the International Institute for Carbon Neutral Energy Research (WPI-I2CNER), sponsored by the Japanese Ministry of Education, Culture, Sports, Science and Technology. Scanning electron microscopy, atomic force microscopy and focused ion beam milling was carried out in part in the Materials Research Laboratory Central Facilities, University of Illinois.
Publisher Copyright:
© 2020 American Chemical Society.
PY - 2020/3/11
Y1 - 2020/3/11
N2 - Scale formation presents an enormous cost to the global economy. Classical nucleation theory dictates that to reduce the heterogeneous nucleation of scale, the surface should have low surface energy and be as smooth as possible. Past approaches have focused on lowering surface energy via the use of hydrophobic coatings and have created atomically smooth interfaces to eliminate nucleation sites, or both, via the infusion of low-surface-energy lubricants into rough superhydrophobic substrates. Although lubricant-based surfaces are promising candidates for antiscaling, lubricant drainage inhibits their utilization. Here, we develop methodologies to deposit slippery omniphobic covalently attached liquids (SOCAL) on arbitrary substrates. Similar to lubricant-based surfaces, SOCAL has ultralow roughness and surface energy, enabling low nucleation rates and eliminating the need to replenish the lubricant. To enable SOCAL coating on metals, we investigated the surface chemistry required to ensure high-quality functionalization as measured by ultralow contact angle hysteresis (<3°). Using a multilayer deposition approach, we first electrophoretically deposit (EPD) silicon dioxide (SiO2) as an intermediate layer between the metallic substrate and SOCAL. The necessity of EPD SiO2 is to smooth (<10 nm roughness) as well as to enable the proper surface chemistry for SOCAL bonding. To characterize antiscaling performance, we utilized calcium sulfate (CaSO4) scale tests, showing a 20× reduction in scale deposition rate than untreated metallic substrates. Descaling tests revealed that SOCAL dramatically decreases scale adhesion, resulting in rapid removal of scale buildup. Our work not only demonstrates a robust methodology for depositing antiscaling SOCAL coatings on metals but also develops design guidelines for the creation of antifouling coatings for alternate applications such as biofouling and high-temperature coking.
AB - Scale formation presents an enormous cost to the global economy. Classical nucleation theory dictates that to reduce the heterogeneous nucleation of scale, the surface should have low surface energy and be as smooth as possible. Past approaches have focused on lowering surface energy via the use of hydrophobic coatings and have created atomically smooth interfaces to eliminate nucleation sites, or both, via the infusion of low-surface-energy lubricants into rough superhydrophobic substrates. Although lubricant-based surfaces are promising candidates for antiscaling, lubricant drainage inhibits their utilization. Here, we develop methodologies to deposit slippery omniphobic covalently attached liquids (SOCAL) on arbitrary substrates. Similar to lubricant-based surfaces, SOCAL has ultralow roughness and surface energy, enabling low nucleation rates and eliminating the need to replenish the lubricant. To enable SOCAL coating on metals, we investigated the surface chemistry required to ensure high-quality functionalization as measured by ultralow contact angle hysteresis (<3°). Using a multilayer deposition approach, we first electrophoretically deposit (EPD) silicon dioxide (SiO2) as an intermediate layer between the metallic substrate and SOCAL. The necessity of EPD SiO2 is to smooth (<10 nm roughness) as well as to enable the proper surface chemistry for SOCAL bonding. To characterize antiscaling performance, we utilized calcium sulfate (CaSO4) scale tests, showing a 20× reduction in scale deposition rate than untreated metallic substrates. Descaling tests revealed that SOCAL dramatically decreases scale adhesion, resulting in rapid removal of scale buildup. Our work not only demonstrates a robust methodology for depositing antiscaling SOCAL coatings on metals but also develops design guidelines for the creation of antifouling coatings for alternate applications such as biofouling and high-temperature coking.
KW - LIS
KW - SLIPS
KW - SOCAL
KW - fouling
KW - hydrophobic
KW - interface
KW - salt
KW - wetting
UR - http://www.scopus.com/inward/record.url?scp=85081944838&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85081944838&partnerID=8YFLogxK
U2 - 10.1021/acsami.9b22145
DO - 10.1021/acsami.9b22145
M3 - Article
C2 - 32045210
AN - SCOPUS:85081944838
SN - 1944-8244
VL - 12
SP - 12054
EP - 12067
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
IS - 10
ER -