Facile Fabrication of Fluorine-Free, Anti-Icing, and Multifunctional Superhydrophobic Surface on Wood Substrates

Abstract

Building superhydrophobic protective layers on the wood substrates is promising in terms of endowing them with multiple functions, including water-repellent, self-cleaning, anti-icing functions. In this study, multifunctional superhydrophobic wood was successfully fabricated by introducing SiO2 sol and superhydrophobic powder (PMHOS). The SiO2 sol was prepared using tetraethoxysilane as a precursor and ethanol was used as the dispersant. The PMHOS was synthesized using poly(methylhydrogen)siloxane (PMHS) and ethanol. As a result, the obtained superhydrophobic wood had a water contact angle (WCA) of 156° and a sliding angle (SA) of 6° at room temperature. The obtained superhydrophobic wood exhibited excellent repellency toward common liquid (milk, soy sauce, juice, and coffee). The superhydrophobic layer on the wood surface also exhibited good durability after a series of mechanical damages, including finger wiping, tape peeling, knife scratching, and sandpaper abrasion. In addition, the obtained superhydrophobic wood showed excellent anti-icing properties.

Recent development and emerging applications of robust biomimetic superhydrophobic wood

“…More recently, Cao et al reported a superhydrophobic wood with repellent abilities toward five kinds of liquid (milk, soy sauce, juice, and coffee), excellent mechanical durability, and anti-icing property, which was fabricated by SiO 2 sol and poly(methylhydrogen)siloxane (PMHS). 88 Concerning the anti-icing test, the wood with the superhydrophobic properties was immersed in water and placed under freezing conditions at −20 °C for 24 h, then removed and allowed to melt at room temperature. As a result, the wood surface maintained the superhydrophobicity with a contact angle larger than 150°.…”

Superhydrophobic Wood Surfaces: Recent Developments and Future Perspectives

“…To prepare SHWSs, the sol-gel method is usually combined with other techniques, such as the hydrothermal synthesis [17], the chemical modification of low-surface-energy materials [106], dipping [177] and electron beam curing [107]. As for the sol-gel methods, reactions need to experience a sol-gel process, which limit the resources of precursors or sols (i.e., SiO 2 sol and TiO 2 sol) for the preparation of SHWSs.…”

“…Due to excellent surface superhydrophobicity, SHWSs has been extensively utilized in various fields, including anti-fungi [16], anti-bacteria [119], oil/water separation [102], fire resistance [133], anti-UV irradiation [156], photo-response [137], electromagnetic interference (EMI) shielding [79], anti-icing [177] and wood-based devices [147]. In this section, we summarize recent applications of SHWSs, and discuss challenges for the versatile application of SHWSs.…”

“…Thus, SHWSs are necessary to be used in wood construction to prevent wood materials from being absorbed by moisture (or water vapor). For example, Cao et al found that the SiO 2 /PMHOS-modified wood samples have good anti-icing properties (Figure 15a) [177]. Zhao et al found that the hydrophobic DH-wood sample only showed a 13% ± 2% thickness expansion (Figure 15(b1,b2)) [134].…”

Study on the Difference of Superhydrophobic Characteristics of Different Wood Furniture Substrates

“…The resulting wood features a water contact angle (WCA) of 156.6°, a rolling angle (SA) of 1.8°, and exhibits considerable wear resistance to severe mechanical damage, such as abrasive paper wear. Cao [ 20 ] achieved the successful production of multifunctional superhydrophobic wood featuring a water contact angle (WCA) of 156° and a rolling angle (SA) of 6° through the incorporation of SiO 2 sol and superhydrophobic powder (PMHOS). The resulting superhydrophobic wood displayed excellent liquid repellency towards common fluids such as milk, soy sauce, juice, and coffee.…”