Fabrication of Ionic Liquid-Functionalized Liquid Metal Composite Hydrogels for Enhanced Antifouling Performance

Marine biofouling imposes significant economic and ecological challenges to maritime activities. Hydrogels are considered effective antifouling materials owing to their highly hydrated surfaces. Herein, nanocomposite hydrogels incorporating ionic liquid-functionalized gallium-based liquid metal (IL-GLM) were successfully fabricated. The ionic liquid (VBBIm⁺Cl^–) was grafted onto the surface of GLM through free radical polymerization, enhancing dispersibility and antifouling efficiency. The resulting IL-GLM microgels were embedded into an acrylic acid/acrylamide hydrogel matrix to form IL-GLM@gel nanocomposite coatings. These coatings exhibited superior antifouling activity and mechanical performance, arising from the synergistic effects of Ga³⁺ release and ionic liquid functionality. Notably, IL-GLM@gel achieved antibacterial and microalgae removal rates exceeding 95 and 85%, respectively, and an increase in tensile strength by 119% and elongation of break by 57%. This study demonstrates that IL-GLM@gel hydrogels hold strong potential as advanced antifouling coatings for marine applications.