The synergy of catalytic nano-enzymes and fouling-release coating: Peroxidase-like Cu NPs composited polysiloxane-based polyurethane PDMS-PUA with enhanced antifouling properties

Marine biofouling presents a significant global challenge today. Silicone-based coatings have garnered considerable interest due to their low surface energy characteristics. However, their practical applications are limited by poor mechanical properties, weak adhesion, and poor static antifouling performance. In response to these inherent limitations, this study innovatively proposed a novel strategy of synergistic nano enzyme-catalyzed sterilization and low surface energy antifouling. A nanocomposite coating, PDMS-PUA-F-Cu, was developed by incorporating peroxidase-like copper nanoparticles (Cu NPs) into a silicone-based polyurethane (PDMS-PUA). The PDMS-PUA was first synthesized through a two-step process using isophorone diisocyanate (IPDI), hydroxy-terminated polydimethylsiloxane (HO-PDMS-OH), and 4,4′-methylenebis(3-chloro-2,6-diethylaniline) (MCDEA) as raw materials. Subsequently, Cu NPs modified with IPDI and polyethylene glycol (PEG) were incorporated into PDMS-PUA to obtain the PDMS-PUA-F-Cu. The resulting coating exhibited enhanced hardness (∼21 MPa) and strong substrate adhesion (∼1.75 MPa) while retaining hydrophobicity and low surface energy. More importantly, the peroxidase-like activity of Cu NPs catalyzed the generation of reactive oxygen species (·OH and ·O 2 − ), enabling dynamic sterilization that significantly enhances the antifouling performance. Experimental results demonstrated outstanding antibacterial rates of ∼98.6 % against Pseudomonas aeruginosa and ∼98.8 % against Staphylococcus aureus , along with remarkable inhibition of Chlorella. adhesion (∼97.4 %). Mechanistic studies confirmed that the synergy between nano enzyme-driven biocidal activity and low surface energy effectively overcame the static antifouling limitations of traditional silicone coatings. This work provides a viable approach for developing high-performance antifouling coatings by combining catalytic sterilization with low-surface-energy coatings.