F₂-laser-induced micro/nanostructuring and surface modification of iron thin film to realize hydrophobic and corrosion resistant

Abstract

Nanoswellings of 60 nm height and 500 nm diameter on average of an iron thin film deposited on a silica glass substrate at regular intervals of 2.5 µm were fabricated by the irradiation of a 157 nm F2 laser. The F2 laser was focused on the iron thin film by each microsphere made of silica glass of 2.5 µm diameter, which covered the entire surface of the films. The surface of the silica glass substrate underneath the F2-laser-irradiated iron thin film selectively swelled to push up the film. After the laser-induced micro/nanostructuring, the F2 laser was again irradiated onto the entire surface of the periodic micro/nanostructured iron thin film to form an approximately 2-nm-thick Fe3O4 modified layer. As a result, the samples showed hydrophobicity and high corrosion resistance to 3 wt % NaCl aqueous solution (quasi-seawater). No rust was observed on the samples after the immersion test in the quasi-seawater for 24 h.

Fabrication of superhydrophobic silicone rubber by ArF-excimer-laser-induced microstructuring for repelling water in water

“…8,9) For the microstructuring, we used microspheres made of silica glass of 2.5 µm diameter, which covered the entire surface of the sample during laser irradiation. 10,11) In the present work, we observed the fabricated microstructure and contact angle of water on the laserirradiated silicone rubber. Moreover, the microstructured silicone rubber was immersed in water to see how the air gap layer can be formed between silicone and water.…”

Fabrication of Superhydrophobic Silicone Rubber with Periodic Micro/Nano-Suction Cup Structure by ArF Excimer Laser-Induced Photodissociation

“…The dispersed solution was dripped on the surface of the Al-coated silicone rubber. Thus, a single layer of microspheres was formed on the Al-coated silicone rubber, in addition to the removal of excess microspheres [21,22].…”

“…When an ArF excimer laser of 193 nm wavelength irradiates the surface of the silicone rubber, the main chain of Si–O bonds of silicone undergoes photodissociation into smaller molecules, resulting in the swelling of the laser-irradiated area [16,17,18,19,20]. For the micro/nanostructuring, microspheres made of silica glass, 2.5 μm in diameter, were used [21,22]. Very recently, we also found that the subsequent formation of a textured nanometer-sized Al thin film resulted in the addition of a nanostructuring effect to the microstructured silicone.…”

Formation of textured Al thin film on silicone rubber to obtain superhydrophobic property

“…In our laboratory, as another approach to obtain a superhydrophobic property using laser, we used our previous photochemical processing of silicone rubber to fabricate the microstructure on the surface; when a 193-nm ArF excimer laser irradiated the surface of silicone rubber, only the main chain of Si-O bonds of silicone could be photodissociated into the lower molecules, resulting in the swelling of the laser-irradiated area [15][16][17][18][19]. For the microstructuring, we used microspheres made of silica glass of 2.5 μm diameter, which covered the entire surface of sample during laser irradiation [14,20]. Very recently, we also found that the subsequent formation of a 50-nm-thick, textured Al thin film resulted in adding a nanostructuring effect to the microstructured silicone, showing a highly superhydrophobic property [21].…”