Functionalization of cellulosic hydrogels with Cu₂O@CuO nanospheres: Toward antifouling applications

Immobilizing metal oxide nanoparticles onto polymer substrate could endow antibacterial performance and enhance mechanical property. In-situ strategy is extensively used to better control loading percentage, uniform distribution and particle size of nanoparticles. However, it still remains challenge in depositing stable bicomponents copper oxide nanoparticles on non-adhesive surface of cellulose hydrogel in high density. In this study, Cu₂O@CuO nanospheres were in-situ deposited onto cellulose hydrogels via liquid phase reduction. Particularly, sodium hydroxide in the cellulose hydrogel severed as the precipitant, which not only save the usage of chemicals, but also enhanced binding between nanoparticles and the hydrogel. Furthermore, Cu₂O@CuO nanospheres demonstrate biocidal antifouling performance against Escherichia coli by releasing biocide. After hydrolysis of precipitation layer, the exposed cellulose hydrogel exhibits fouling-resistant property for Chlorella Vulgaris due to the hydration layer on its surface. Such composites hold great promise in antifouling coatings and other applications.