Any equipment submerged in the ocean will have its surface attacked by fouling organisms, which can cause serious damage. Traditional antifouling coatings contain heavy metal ions, which also have a detrimental effect on the marine ecological environment and cannot fulfill the needs of practical applications. As the awareness of environmental protection is increasing, new environmentally friendly and broad-spectrum antifouling coatings have become the current research hotspot in the field of marine antifouling. This review briefly outlines the formation process of biofouling and the fouling mechanism. Then, it describes the research progress of new environmentally friendly antifouling coatings in recent years, including fouling release antifouling coatings, photocatalytic antifouling coatings and natural antifouling agents derived from biomimetic strategies, micro/nanostructured antifouling materials and hydrogel antifouling coatings. Highlights include the mechanism of action of antimicrobial peptides and the means of preparation of modified surfaces. This category of antifouling materials has broad-spectrum antimicrobial activity and environmental friendliness and is expected to be a new type of marine antifouling coating with desirable antifouling functions. Finally, the future research directions of antifouling coatings are prospected, which are intended to provide a reference for the development of efficient, broad-spectrum and green marine antifouling coatings.

An innovative antifouling composite coating comprising dopamine (DA), polyethyleneimine (PEI), and silica (SiO₂) was developed through a straightforward and environmentally friendly approach. Initially, silica nanoparticles comodified with DA and PEI were meticulously deposited onto 304 stainless steel surfaces pretreated with dopamine to achieve a uniformly distributed nanocomposite surface. Comprehensive analytical techniques, including Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectrometry (XPS), field emission scanning electron microscopy (SEM), contact angle measurement (CA), and 3D optical profilometry, were employed to affirm the successful preparation of the silica nanocomposite coatings and the effective grafting of MAG II. The antibacterial and antibiofilm performance of the DA/PEI/SiO₂-modified surface was rigorously assessed using Vibrio natriegens (V. natriegens), yielding compelling results indicating a substantial 51.4% reduction in biofilm formation on the SS-DA/PEI/SiO₂ sample surfaces, coupled with an impressive 95.2% decrease in V. natriegens adhesion. This pioneering research introduces an innovative strategy for the development of antimicrobial surfaces with promising applications in medical devices, aquaculture, and related fields.