Antifouling painting formulations containing green synthesized copper oxide nanoparticles using water extract of Ulva fasciata

Recently, nanotechnology-based paints have been employed in the field of biofouling prevention. The green production of copper oxide nanoparticles (GB-CuONPs) with Ulva fasciata water extract was described in this study. The aqueous U. fasciata extract contains diverse compounds that act as reducing and stabilizing agents for GB-CuONPs. The GB-CuONPs were characterized by different instruments. SEM indicated monoclinic phase (tenorite) clustered nanoparticles. EDX spectrum comprised C, N, Zn, Cu, and O peaks. FT-IR showed peaks that could be attributed to proteins, carbohydrates and polyphenols. The average crystallite size was 35.2 nm. XRD assigned the reflection lines of monoclinic GB-CuONPs. The antimicrobial activity of GB-CuONPs was studied against three Gram-negative and two Gram-positive bacterial strains. Antifouling efficacy of different concentrations (0, 0.25, 0.50, 1.00, and 1.50%) from GB-CuONPs was evaluated in situ for 200 days. Low weights of fouling organisms were formed on all the panels, ranging between 0.0495 and 0.1451 g/cm². Their effectiveness may be attributed to the biocide’s gradual release from the coatings. Panels treated with formulations containing (1.00% and 1.50%) GB-CuONPs showed good antifouling activity during the study period, with only 5% of barnacles. The surrounding seawater parameters of the immersed coated steel panels were within the typical range for this area.