Superhydrophobic Silicone/TiO2-SiO2 Nanorod-like Composites for Marine Fouling Release Coatings

For the first time, a superhydrophobic series of silicone/nanorod-like TiO2-SiO2 core-shell composites was fabricated by solution casting for marine fouling release (FR) coatings. Hydrothermal technique was used to prepare single crystal TiO2 nanorods as a core structure in the diameter regime of 20 nm and preferentially grown in {101} direction. Hybrid nanorod-like TiO2-SiO2 core-shell nanofillers were synthesized by sol-gel technique with silica shell thickness of 2-5 nm. The structure-property relationship was investigated by dispersing various nanofiller concentrations in the silicone matrix. Surface non-wettability properties were investigated using water contact angle (WCA), surface free energy (SFE), and atomic force microscopy. Coating ' s photocatalytic degradation of organic pollutants and microorganisms was also investigated. Selected micro- and macro-fouling strains were used for antifouling assessments in laboratory. The fabricated models were subjected to a rigorous field trial in natural seawater for 6 months in a tropical area. Well-distributed nanorod-like TiO2-SiO2 core-shell (0.5 wt.%) exhibited the preferable FR self-cleaning with WCA of 154 degrees and SFE of 10.45 mN/m.