Indexed by:期刊论文

Date of Publication:2021-01-10

Journal:SURFACE & COATINGS TECHNOLOGY

Volume:400

ISSN No.:0257-8972

Key Words:Patterned surface; Laser texturing; Wettability change; Superhydrophilic

Abstract:Patterned surfaces that show different wettabilities on same substrates have important application value in fields like fog collection and liquid transportation. However, superhydrophilic regions on the patterned surfaces prepared tend to become superhydrophobic, which restrains their further applications. Therefore, it is of great significance to explore wettability change of the superhydrophilic regions. In this paper, we prepare patterned aluminum (Al) surfaces by nanosceond laser texturing and fluorosilane modification, and investigate the wettability change of the patterned surfaces (laser parameters: a pulse repetition rate of 20 kHz, a scanning speed of 300 mm/s, a power of 6 W, a pulse width of 100 ns, a beam waist diameter of 46 mu m, an optical wavelength of 1064 +/- 5 nm, a pulse energy of 0.3 mJ and a laser fluence of 18 J/cm(2)). Contact angles, surface morphologies and surface chemical compositions are measured and analyzed by an optical angle meter, a scanning electron microscope, and X-ray photoelectron spectroscopy. Compared with a uniform superhydrophilic surface, the superhydrophilic area on a patterned surface becomes superhydrophobic more rapidly, indicating that cross contamination of low surface energy functional groups from the superhydrophobic region promotes wettability change of the superhydrophilic region. In addition, the wettability change rate gradually accelerates when storing under a higher temperature of 100 degrees C; we perform fog collection experiments on patterned surfaces storing under different temperatures, and find that low temperature can hinder wettability change of functional patterned surfaces, thereby improving service life.