Antifouling Effects of Superhydrophobic Coating on Sessile Marine Invertebrates

Biofouling is a significant problem in the aquaculture and marine shipping industries; thus, various antifouling methods have been developed to prevent the resultant economic losses. In the present study, the superhydrophobic surface of a lotus leaf was bio-mimicked to achieve antifouling. Specifically, fabric substrates with and without superhydrophobic coatings on the surface were installed on the Tongyeong yacht in December 2020 (group A) and April 2021 (group B), and the coverage of the attached invertebrates was recorded every month until August 2021. The coverage of solitary ascidians (Ascidiella aspersa and Ciona robusta) and branching bryozoans (Bugula neritina) was lower on the coated substrates than on the non-coated ones, and coating or non-coating was significantly correlated with the extent of coverage. Superhydrophobic substrates with a low surface energy and micro-nano dual structure may be unsuitable for the attachment of larvae. Therefore, superhydrophobic coating is a more effective and simpler method of antifouling for certain taxa than other antifouling strategies. However, the antifouling effect of the superhydrophobic substrate in group A reduced after 5 months from the first installation; thus, the durability of the antifouling coating should be further improved, and solving this problem remains a major task, necessitating further research.