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.

Non-fluorinated superhydrophobic and micro/nano hierarchical Al doped ZnO film: the effect of Al doping on morphological and hydrophobic properties

“…The most common superhydrophobic surface can be fabricated via chemically modifying with low surface free energy organic peruorinated materials. [7][8][9][10][11] Being a wide band-gap semiconductor material, zinc oxide (ZnO) possesses various optical and electrical applications. 6 Therefore, increasing attention is drawn to fabricating superhydrophobic surfaces without any low energy organic materials, such as inorganic material lms with specic hierarchical rough surfaces.…”

A sol–bath–gel approach to prepare hybrid coating for corrosion protection of aluminum alloy

“…However, aluminum alloys can be chemically reactive and highly susceptible to corrosion in aggressive environments, which significantly limits their applications [3,4]. Therefore, the protection of aluminum alloys from unwanted corrosion has been an important issue, which has attracted significant attention.…”

“…3b) can be resolved into two components with binding energies of 74.2 and 76.6 eV. The peak at 74.2 eV is assigned to AlOOH and the one at 76.6eV is assigned to Al(OH)3 [3,14] . The Si 2p peak(Fig.…”

Mechanically durable superoleophobic aluminum surfaces with microstep and nanoreticula hierarchical structure for self-cleaning and anti-smudge properties

“…Various techniques, including chemical etching and anodization techniques, have been used to produce superhydrophobic aluminum surfaces. Chemical etching method with various chemical etchants including boiling water [31,15], NaOH [12,22], HCl [30], ZnNO 3 Á6H 2 O [39,24], HNO 3 combined with Cu(NO 3 ) 2 [11,23], AlCl 3 combined with triethanolamine [21], La(NO 3 ) 3 [20], and FeCl 3 [25], and anodization method, with various electrolytes including oxalic acid [19,27], mixed solutions of NaCl and fluorosilane [33], have been used to prepare superhydrophobic aluminum surfaces. In the above-mentioned papers, nanoplatelet, microstep, nanoreticula, microflower, and nanowire structures have been created to achieve superhydrophobicity.…”