title: Robust biomimetic-structural superhydrophobic surface on aluminum alloy.
abstract: The following facile approach has been developed to prepare a biomimetic-structural superhydrophobic surface with high stabilities and strong resistances on 2024 Al alloy that are robust to harsh environments. First, a simple hydrothermal treatment in a La(NO3)3 aqueous solution was used to fabricate ginkgo-leaf like nanostructures, resulting in a superhydrophilic surface on 2024 Al. Then a low-surface-energy compound, dodecafluoroheptyl-propyl-trimethoxylsilane (Actyflon-G502), was used to modify the superhydrophilic 2024 Al, changing the surface character from superhydrophilicity to superhydrophobicity. The water contact angle (WCA) of such a superhydrophobic surface reaches up to 160°, demonstrating excellent superhydrophobicity. Moreover, the as-prepared superhydrophobic surface shows high stabilities in air-storage, chemical and thermal environments, and has strong resistances to UV irradiation, corrosion, and abrasion. The WCAs of such a surface almost remain unchanged (160°) after storage in air for 80 days, exposure in 250 °C atmosphere for 24 h, and being exposed under UV irradiation for 24 h, are more than 144° whether in acidic or alkali medium, and are more than 150° after 48 h corrosion and after abrasion under 0.98 kPa for 1000 mm length. The remarkable durability of the as-prepared superhydrophobic surface can be attributed to its stable structure and composition, which are due to the existence of lanthanum (hydr)oxides in surface layer. The robustness of the as-prepared superhydrophobic surface to harsh environments will open their much wider applications. The fabricating approach for such robust superhydrophobic surface can be easily extended to other metals and alloys.
authors.affiliation: School of Chemistry and Chemical Engineering, Chongqing University , Chongqing 400044 People's Republic of China.
authors.forename: Lingjie
authors.initials: L
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Huang
authors.forename: Jinglei
authors.initials: J
authors.lastname: Lei
authors.forename: Jianxin
authors.initials: J
authors.lastname: He
authors.forename: Linfeng
authors.initials: L
authors.lastname: Qu
authors.forename: Peiling
authors.initials: P
authors.lastname: Huang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.forename: Nianbing
authors.initials: N
authors.lastname: Li
authors.forename: Fusheng
authors.initials: F
authors.lastname: Pan
mesh_terms: D000497:Alloys / Q000737:chemistry*; D000535:Aluminum / Q000737:chemistry*; D040761:Biomimetic Materials / Q000737:chemistry*; D032701:Biomimetics / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D013499:Surface Properties
chemical_list: D000497:Alloys; D000535:Aluminum
keywords: aluminum alloy; biomimetic structure; durability; hydrothermal method; superhydrophobic surface